JP7322652B2 - Control device for internal combustion engine - Google Patents

Description

The present invention relates to a control device for an internal combustion engine.

2. Description of the Related Art In an internal combustion engine in which a piston reciprocates within a cylinder, a piston ring is fitted in a ring groove provided on the outer peripheral surface of the piston. The piston ring is in close contact with the inner wall of the cylinder together with lubricating oil (oil film) on the inner wall of the cylinder, and seals the combustion chamber surrounded by the cylinder head, the cylinder and the piston. A piston ring seals a combustion chamber in each process such as a combustion process of an internal combustion engine, and also retains and discharges lubricating oil on the inner wall of the cylinder in order to keep the inner wall of the cylinder lubricated. Therefore, there is a flow of lubricating oil due to retention/discharging on the inner wall of the cylinder, and a flow of lubricating oil is also present between the ring groove of the piston and the piston ring. A part of the lubricating oil is carbonized and becomes deposits (foreign matter) due to the high-temperature and high-pressure gas generated by the combustion process of the internal combustion engine. Deposits (foreign matter) adhering to the inner wall of the cylinder are scraped off by the piston ring, but if the lubricating oil flowing around the piston ring, such as between the ring groove and the piston ring, is carbonized, it will accumulate as deposits (foreign matter). Sometimes.

When deposits (foreign matter) build up around the piston ring, the movement of the piston ring (diameter expansion, diameter reduction, etc.) is hindered, affecting the sealing performance between the piston ring and the cylinder inner wall (and oil film). If the amount of deposits (foreign matter) builds up further, the sealing performance between the piston ring and the inner wall of the cylinder (and the oil film) may deteriorate significantly. If the sealing performance between the piston ring and the inner wall of the cylinder (and the oil film) deteriorates significantly, various problems may occur, such as an increase in the amount of blow-by gas leaking from the combustion chamber into the crankcase.

Therefore, for example, in Patent Document 1, a pressure sensor capable of detecting the dynamic crankcase internal pressure corresponding to the rotation angle of the crankshaft is arranged in the crankcase, and based on the change in the crankcase internal pressure at predetermined crank angle intervals, A blow-by gas detection method for a four-cycle, multiple-cylinder engine is disclosed that detects changes in blow-by gas pressure for each cylinder. According to the blow-by gas detection method described in Patent Document 1, it is possible to identify a cylinder in which the amount of blow-by gas is abnormally increasing.

Patent Document 2 discloses a blow-by gas detector that can detect the pressure of engine blow-by gas using a normal pressure head without using a special measuring instrument such as a micromanometer or a U-tube (manometer). disclosed. The blow-by gas detection device includes a hydraulic differential pressure gauge, a hydraulic pump that pumps hydraulic oil to the hydraulic differential pressure gauge, a pressure head that is connected to a pressure port of the hydraulic differential pressure gauge to detect the output pressure, and a hydraulic pump. It has a pressure sensor provided between the hydraulic differential pressure gauges, a rotation sensor for detecting the number of rotations of the engine, a controller, a display, and an alarm. The blow-by gas detection device can constantly monitor whether there is an abnormality in the engine.

JP 2009-85177 A JP-A-6-185336

In the blow-by gas detection method described in Patent Document 1, it is necessary to take in the blow-by gas pressure and various associated processes at predetermined crank angle intervals, so the processing load at a predetermined crank angle increases. For example, in a diesel engine, multi-stage fuel injection is controlled with high accuracy at a predetermined crank angle. More processing at angles is less preferred. In addition, in a gasoline engine, the control of fuel injection at a predetermined crank angle is somewhat simplified, but high-precision ignition control at a predetermined crank angle is added, so increasing the processing at a predetermined crank angle is not so desirable.

Further, in Patent Document 1, normality/abnormality can be determined for each cylinder, but when an abnormality is detected, overhaul such as cleaning of the piston of the target cylinder and replacement of the piston ring is performed. However, when performing an overhaul, it is not possible to disassemble only the target cylinder in the structure of a general internal combustion engine, and all cylinders must be disassembled. Also, since overhauling is a labor-intensive and time-consuming task, once the engine has been disassembled, not only the piston of the target cylinder but also the other cylinders are generally serviced. In other words, even if you identify the cylinder in which an abnormality has occurred, it is not possible to identify the cylinder. If it is possible to detect that an abnormality has occurred, it is not necessary to specify the cylinder.

In addition, the blow-by gas detection device described in Patent Document 2 requires a hydraulic differential pressure gauge, a hydraulic pump, a pressure head, a pressure sensor, etc. as dedicated parts for detecting the blow-by gas pressure, which complicates the system. , since a space for mounting them is also required, it is not so preferable.

The present invention has been invented in view of the above points, and has a simpler configuration and a process with a lighter load to detect an abnormality in the blow-by gas and remove foreign matter around the piston ring. An object of the present invention is to provide a control device for an internal combustion engine that can appropriately detect deposits.

In order to solve the above-described problems, a first invention of the present invention is a control device for an internal combustion engine that detects the presence or absence of deposits of foreign matter around a piston ring of an internal combustion engine, the control device comprising: an operating state detector that detects an operating state of the engine; and a first crankcase that acquires, for a first predetermined time, a crankcase internal pressure, which is the pressure in the crankcase of the internal combustion engine, which is one of the operating states. When the internal pressure acquisition unit detects a pressure step that is a step-like fluctuation amount of the acquired crankcase internal pressure, the presence or absence of an abnormal step that is a pressure step that is larger than the abnormal step pressure set as a threshold value for abnormality determination is determined. and an abnormality detection unit that detects whether or not the foreign matter is deposited around the piston ring of the internal combustion engine based on the above.

Next, a second aspect of the present invention is a control device for an internal combustion engine for detecting the presence or absence of deposits of foreign matter around piston rings of an internal combustion engine, wherein the control device includes: A reference crankcase internal pressure characteristic in which a reference internal pressure, which is a reference pressure in the crankcase when the foreign matter is not accumulated, is set according to the operating state of the internal combustion engine is stored in the control unit. The device includes an operating state detection unit that detects the operating state of the internal combustion engine, and acquires a crankcase internal pressure, which is the pressure in the crankcase of the internal combustion engine, which is one of the operating states, for a first predetermined time. The first crankcase internal pressure acquisition unit obtains a pressure deviation, which is a deviation between the obtained crankcase internal pressure and the reference internal pressure obtained based on the operating state and the reference crankcase internal pressure characteristic, and determines an abnormality. an abnormality detection unit that detects the presence or absence of deposition of the foreign matter around the piston ring of the internal combustion engine based on the presence or absence of the pressure deviation that is equal to or higher than the abnormality determination pressure set as the threshold value of A control device for an internal combustion engine.

Next, a third invention of the present invention is a control device for an internal combustion engine according to the first invention or the second invention, wherein the control device reduces blow-by gas in a crankcase of the internal combustion engine to the above-mentioned The control device for an internal combustion engine obtains the crankcase internal pressure using pressure detection means provided in a blow-by gas path leading to an intake path of the internal combustion engine.

Next, a fourth invention of the present invention is a control device for an internal combustion engine according to the second invention, wherein the control device detects the abnormality when the operating state of the internal combustion engine is not an idling state. section detects the presence or absence of deposition of the foreign matter around the piston ring of the internal combustion engine, and the abnormality determination pressure is determined by the operating state of the internal combustion engine and the reference crankcase when the pressure deviation is obtained. half or less of the pressure difference between the reference internal pressure obtained based on the internal pressure characteristic and the reference internal pressure obtained based on the operating state and the reference crankcase internal pressure characteristic when the internal combustion engine is in an idling state. A control device for an internal combustion engine, which is a set value.

Next, a fifth invention of the present invention is a control device for an internal combustion engine according to any one of the first invention to the fourth invention, wherein the control device comprises, in the abnormality detection section, a second crankcase internal pressure acquisition unit configured to acquire the crankcase internal pressure for a second predetermined time when it is detected that the foreign matter is deposited around the piston ring of the internal combustion engine; and the second crank. an abnormality re-detection unit that executes processing of the abnormality detection unit in correspondence with acquisition of the crankcase internal pressure by the case internal pressure acquisition unit; a control device for an internal combustion engine, comprising: an abnormality confirmation determination unit that confirms that there is accumulation of the foreign matter around the piston ring of the internal combustion engine when it is detected that the foreign matter has accumulated on the piston ring of the internal combustion engine be.

Next, a sixth invention of the present invention is a control apparatus for an internal combustion engine according to the fifth invention, wherein the internal combustion engine is mounted on a vehicle, and the vehicle is provided with notification means. When the abnormality confirmation determination unit makes the confirmation determination, the control device uses the notification means to notify that there is deposition of the foreign matter around the piston ring of the internal combustion engine. A control device for an internal combustion engine.

Next, a seventh invention of the present invention is a control device for an internal combustion engine according to the sixth invention, wherein the control device removes the foreign matter accumulated around the piston ring of the internal combustion engine. The vehicle has a foreign matter removing operation executing section capable of executing a foreign matter removing operation mode, and the foreign matter removing operation instruction input enabling an instruction to start the foreign matter removing operation mode when the confirmation determination is made to the vehicle. A control device for an internal combustion engine, wherein means are provided.

Next, an eighth invention of the present invention is a control device for an internal combustion engine according to the seventh invention, wherein the control device executes the foreign matter removal operation mode in the foreign matter removal operation execution section. and a control apparatus for an internal combustion engine, wherein, as a result of execution, whether or not the foreign matter deposited around the piston ring of the internal combustion engine has been removed is reported using the reporting means.

Next, a ninth invention of the present invention is the control device for an internal combustion engine according to the eighth invention, wherein the control device instructs the start of the foreign matter removal operation mode from the foreign matter removal operation instruction input means. and after the foreign matter removal operation mode by the foreign matter removal operation execution unit is completed, the operation state of the internal combustion engine is set to a predetermined operation state. a third crankcase internal pressure acquiring unit for acquiring the crankcase internal pressure for a third predetermined time; and executing the process of the abnormality detecting unit corresponding to the acquisition of the crankcase internal pressure by the third crankcase internal pressure acquiring unit. and a foreign matter removal confirmation unit that detects whether or not the foreign matter is deposited around the piston ring of the internal combustion engine.

Next, a tenth invention of the present invention is the control device for an internal combustion engine according to the ninth invention, wherein the control device is configured such that, in the foreign matter removal confirming section, the piston ring of the internal combustion engine is moved around the piston ring of the internal combustion engine. When it is detected that there is no deposition of the foreign matter, the notifying means is used to notify that the removal of the foreign matter has been completed, and the foreign matter removal confirmation unit detects the presence of the foreign matter around the piston ring of the internal combustion engine. A control device for an internal combustion engine, comprising a foreign matter removal operation result notification unit that uses the notification means to notify, when it is detected that there is an accumulation of foreign matter, that the vehicle is to be brought to a dealership.

Next, an eleventh invention of the present invention is a control device for an internal combustion engine according to any one of the seventh invention to the tenth invention, wherein the control device operates in the foreign object removal operation mode. a fuel sweep increase control for gradually increasing the fuel injection amount for a predetermined period of time to promote moistening of the foreign matter; A control device for an internal combustion engine, which repeats a fuel sweep reduction control that promotes drying and a predetermined number of times to promote separation of the foreign matter around the piston ring.

Next, a twelfth invention of the present invention is the control apparatus for an internal combustion engine according to the eleventh invention, wherein the fuel injection amount reduced by the fuel sweep reduction control is determined by the temperature of the piston of the internal combustion engine. A control device for an internal combustion engine, which is set to decrease the fuel injection amount until the temperature reaches 300° C. or higher.

Next, a thirteenth invention of the present invention is a control device for an internal combustion engine according to any one of the seventh invention to the twelfth invention, wherein the control device operates in the foreign object removal operation mode. executing a piston swing control in which a piston center axis, which is a center axis of a piston of the internal combustion engine, swings with respect to a cylinder center axis, which is a center axis of a cylinder of the internal combustion engine; It is the engine control device.

Next, a fourteenth invention of the present invention is the control apparatus for an internal combustion engine according to the thirteenth invention, wherein the piston swing control repeats stepwise advance and retard of the fuel injection timing. A control device for an internal combustion engine, which is at least one of fuel injection timing step advance/retard control and fuel step increase/decrease control that repeats a stepwise increase and decrease of a fuel injection amount.

Next, a fifteenth invention of the present invention is a control device for an internal combustion engine according to the thirteenth invention, wherein the internal combustion engine is provided with a supercharger, and the piston oscillation control is performed by injecting fuel. Fuel injection timing step advance/retard control that repeats stepwise advance and retard of timing, fuel step increase/decrease control that repeats stepwise increase and decrease of fuel injection amount, boost pressure or exhaust manifold internal pressure A boost pressure/exhaust pressure step increase/decrease control that repeats a stepwise increase and decrease of (1).

According to the first invention, instead of dynamically detecting the internal pressure of the crankcase according to the crank angle, the overall static internal pressure of the crankcase is captured for the first predetermined period of time. By detecting whether or not there is a pressure step larger than the abnormal pressure step in the internal pressure (a pressure step that is a step-like fluctuation amount), it is possible to detect the presence or absence of deposits of foreign matter around the piston ring. Therefore, it is sufficient to statically detect the internal pressure of the crankcase, and there is no need for severe detection timing. can be detected appropriately. Further, by detecting the "pressure step" of the internal pressure of the crankcase, it is possible to easily determine whether or not there is an abnormality.

According to the second invention, instead of dynamically detecting the internal pressure of the crankcase according to the crank angle, the overall static internal pressure of the crankcase is captured for the first predetermined period of time. Abnormality is detected based on the pressure deviation between the internal pressure and the reference internal pressure (at normal time) to detect the presence or absence of deposits of foreign matter around the piston ring. Therefore, it is sufficient to statically detect the internal pressure of the crankcase, and there is no need for severe detection timing. can be detected appropriately. In addition, it is easy to obtain the reference internal pressure from the reference crankcase internal pressure characteristic, and it is also easy to obtain the pressure deviation between the actual crankcase internal pressure and the reference internal pressure. can.

According to the third invention, the static internal pressure within the overall crankcase can be appropriately detected. In addition, in an internal combustion engine system that already has a pressure detection means in the blow-by gas path, there is no need to provide a new pressure detection means, which is convenient.

According to the fourth invention, it is easy to set the value of the abnormality determination pressure to an appropriate value.

According to the fifth aspect of the invention, when it is detected that foreign matter has accumulated around the piston ring at the crankcase internal pressure acquired during the first predetermined time period, the engine is again controlled for the second predetermined time period just in case. Since the presence or absence of accumulation of foreign matter is reconfirmed using the crankcase internal pressure acquired during the period, erroneous determination can be suppressed.

According to the sixth invention, it is possible to appropriately notify the user that it has been determined that there is foreign matter deposited around the piston ring, so that the user can be notified that some kind of treatment is required.

As a measure for the accumulation of foreign matter around the piston ring, an overhaul is generally performed by dismantling and servicing the internal combustion engine. However, according to the seventh invention, by having the foreign matter removing operation instruction input means and the foreign matter removing operation mode, it is possible to take measures to remove the accumulated foreign matter without overhauling, which is convenient. be.

Although there is a possibility that the foreign matter is not removed even when the foreign matter removal operation mode is executed, according to the eighth invention, it is possible to confirm whether or not the foreign matter has been removed in the foreign matter removal operation mode. so convenient.

According to the ninth invention, it is convenient to check whether or not the foreign matter has been removed after executing the foreign matter removal operation mode.

According to the tenth invention, when it is detected that the foreign matter has not been removed as a result of checking whether the foreign matter has been removed, the user is prompted to bring the vehicle to a shop (a so-called dealer). can be prevented from being left unattended.

According to the eleventh invention, in the foreign matter removal operation mode, the fuel sweep increase control and the fuel sweep decrease control are repeated to repeatedly moisten the foreign matter and dry the foreign matter, thereby appropriately promoting the separation of the foreign matter. can be done.

According to the twelfth invention, in the fuel sweep reduction control, the fuel injection amount is set to be reduced until the piston temperature reaches 300 [° C.] or more, so foreign matter can be dried more reliably.

According to the thirteenth aspect of the present invention, by swinging the piston so that the piston center axis swings with respect to the cylinder center axis, it is possible to facilitate shaking off foreign matter.

According to the fourteenth invention, the piston swing control can be specifically and appropriately executed in at least one of the fuel injection timing step advance/retard control and the fuel step increase/decrease control.

According to the fifteenth invention, in at least one of the fuel injection timing step advance/retard control, the fuel step increase/decrease control, and the boost pressure/exhaust pressure step increase/decrease control, the piston swing control is Able to execute concretely and appropriately.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram illustrating an overall schematic configuration of an example of an internal combustion engine system having a control device for an internal combustion engine according to the present invention; FIG. 2 is a diagram illustrating cross sections of a cylinder block and a crankcase, positions of pressure detecting means for detecting internal pressure of the crankcase, and the like; It is a perspective view explaining the schematic structure of a piston and a piston ring. FIG. 4 is a diagram illustrating an example of the relationship between the position of a gap between piston rings of a piston arranged in a cylinder and the position of accumulation of foreign matter; FIG. 5 is a cross-sectional view for explaining a contact state between a cylinder inner wall and a piston ring and a gap between the piston ring and the piston; 6 is a flowchart for explaining an example of a processing procedure (overall processing) of the control device in the first embodiment; FIG. 7 is a flowchart for explaining the details of SA100 (foreign object detection processing) in the flowchart shown in FIG. 6; FIG. FIG. 8 is a flowchart for explaining details of SA200 (abnormality detection processing) in the flowchart shown in FIG. 7; FIG. FIG. 9 is a diagram for explaining the operation of SA200 (abnormality detection processing) shown in FIG. 8; FIG. 8 is a flowchart for explaining the details of SA300 (abnormality re-detection processing) in the flowchart shown in FIG. 7; FIG. FIG. 7 is a flowchart for explaining the details of SB100 (foreign matter removal process [foreign matter removal operation mode]) in the flowchart shown in FIG. 6 ; FIG. FIG. 12 is a flowchart for explaining the details of SB200 (fuel sweep increase/decrease control (1)) in the flowchart shown in FIG. 11; FIG. FIG. 12 is a flowchart for explaining the details of SB300 (fuel sweep increase/decrease control (2)) in the flowchart shown in FIG. 11; FIG. FIG. 12 is a flow chart explaining the details of SB400 (boost pressure/exhaust pressure step increase/decrease control) in the flow chart shown in FIG. 11; FIG. FIG. 12 is a flowchart for explaining the details of SB500 (fuel injection timing step advance/retard control) in the flowchart shown in FIG. 11; FIG. FIG. 12 is a flowchart for explaining the details of SB600 (fuel step increase/decrease control) in the flowchart shown in FIG. 11; FIG. FIG. 7 is a flowchart for explaining the details of SC100 (post-removal confirmation process) in the flowchart shown in FIG. 6. FIG. FIG. 18 is a flowchart for explaining details of SC200 (abnormality re-detection processing) in the flowchart shown in FIG. 17; FIG. 7 is a flowchart illustrating an example of fixing the turbo switching mode during the foreign object removal operation mode; An example of switching the fuel injection amount between the injection amount for the foreign matter removal operation mode and the injection amount for checking the result of the foreign matter removal operation mode during the foreign matter removal operation mode and confirmation of the result of the foreign matter removal operation mode will be described. It is a flow chart. 7 is a flowchart illustrating an example of switching the degree of closure of the variable nozzle of the turbine to the degree of closure for the foreign matter removal operation mode during the foreign matter removal operation mode; 7 is a flowchart illustrating an example of switching the fuel injection timing to the injection timing for the foreign matter removal operation mode during the foreign matter removal operation mode; It is an operation waveform explaining a foreign substance removal operation mode. FIG. 10 is a flowchart illustrating an example of a processing procedure (overall processing) of a control device in the second embodiment; FIG. FIG. 25 is a flowchart for explaining details of SD100 (foreign object detection processing) in the flowchart shown in FIG. 24; FIG. FIG. 26 is a diagram for explaining the operation of SD100 (foreign object detection process) shown in FIG. 25; FIG. 5 is a diagram illustrating an example of a reference crankcase internal pressure characteristic; FIG. 25 is a flowchart for explaining details of SE100 (post-removal confirmation processing) in the flowchart shown in FIG. 24; FIG.

● [Example of overall schematic configuration of internal combustion engine system 1 (Fig. 1)]
Embodiments for carrying out the present invention will be described below with reference to the drawings. First, with reference to FIG. 1, an example of an overall schematic configuration of an internal combustion engine system 1 having an internal combustion engine control device 70 will be described. In the description of the present embodiment, an internal combustion engine 10 (for example, a diesel engine) mounted on a vehicle is used as an example of the internal combustion engine. Moreover, in the example of the internal combustion engine system 1 shown in FIG. 61, the serial supercharging operation of the second supercharger 32 and the first supercharger 31 is also possible.

Hereinafter, the entire internal combustion engine system 1 will be described in order from the intake side (upper side in FIG. 1) to the exhaust side (lower side in FIG. 1) using FIG. On the inflow side of the intake pipe 11A, an intake air flow rate detection means 21 (for example, an intake flow rate sensor), an atmospheric pressure detection means 22D (for example, a pressure sensor), and an intake air temperature detection means 22E (for example, a temperature sensor) are provided. there is The intake flow rate detection means 21 outputs a detection signal corresponding to the flow rate of the air taken in by the internal combustion engine 10 to the control device 70 . The atmospheric pressure detection means 22D outputs a detection signal corresponding to the atmospheric pressure of the atmosphere (atmospheric pressure) to the control device 70, and the intake air temperature detection means 22E detects the temperature of the air taken in by the internal combustion engine 10 (inside the intake pipe 11A). temperature of the air) is output to the control device 70 . The outflow side of the intake pipe 11A is bifurcated into intake pipes 11B1 and 11B2, and is connected to the inflow side of the intake pipe 11B1 and the inflow side of the intake pipe 11B2.

The outflow side of the intake pipe 11B1 is connected to the inflow side of the compressor 31A of the first supercharger 31 (first turbocharger). An outflow side of an intake bypass pipe 11CB is connected in the middle of the intake pipe 11B1. The outflow side of the compressor 31A is connected to the inflow side of the intake pipe 11C1, and the outflow side of the intake pipe 11C1 joins the outflow side of the intake pipe 11C2 and is connected to the inflow side of the intake pipe 11D. The compressor 31A is rotationally driven by a turbine 31B that rotates using the energy of the exhaust gas, compresses air sucked from the intake pipe 11B1, and discharges (supercharges) the air to the intake pipe 11C1.

The outflow side of the intake pipe 11B2 is connected to the inflow side of the compressor 32A of the second turbocharger 32 (second turbocharger). The outflow side of the compressor 32A is bifurcated into an intake pipe 11C2 and an intake bypass pipe 11CB, and is connected to the inflow side of the intake pipe 11C2 and the inflow side of the intake bypass pipe 11CB. The outflow side of the intake pipe 11C2 joins the outflow side of the intake pipe 11C1 and is connected to the inflow side of the intake pipe 11D. An intake switching valve 62 that opens and closes the intake pipe 11C2 based on a control signal from the control device 70 is provided in the intake pipe 11C2. The outflow side of the intake bypass pipe 11CB is connected to the intake pipe 11B1. The intake bypass pipe 11CB is also provided with an intake bypass valve 61 that opens and closes the intake bypass pipe 11CB based on a control signal from the control device 70 .

The turbine 32B that rotationally drives the compressor 32A is rotationally driven by the energy of the exhaust gas when the exhaust switching valve 63 is opened. The exhaust switching valve 63 opens and closes the exhaust pipe 12B2 based on a control signal from the control device . When the exhaust switching valve 63 is opened and the turbine 32B is rotationally driven, the control device 70 opens one of the intake switching valve 62 and the intake bypass valve 61 and closes the other. Further, when the exhaust switching valve 63 is closed, the control device 70 closes both the intake switching valve 62 and the intake bypass valve 61 .

When the compressor 32A is rotationally driven by the turbine 32B, when the intake switching valve 62 is open and the intake bypass valve 61 is closed, the compressor 32A compresses the air taken in from the intake pipe 11B2 and discharges it to the intake pipe 11C2 ( supercharge). Further, when the compressor 32A is rotationally driven by the turbine 32B, when the intake switching valve 62 is closed and the intake bypass valve 61 is open, the compressor 32A compresses the air taken in from the intake pipe 11B2 to the intake bypass pipe 11CB. Discharge (supercharge).

The inflow side of the intake pipe 11D is connected to the outflow side of the intake pipe 11C1 and the outflow side of the intake pipe 11C2, and the outflow side of the intake pipe 11D is connected to the inflow side of the intake manifold 11E. Any one of the intake pipe 11C1, the intake pipe 11D, and the intake manifold 11E downstream of the compressor 31A of the first supercharger 31 is provided with a supercharging pressure detecting means 22A (for example, a pressure sensor) for detecting the supercharging pressure. ) is provided. The boost pressure detection means 22A outputs a detection signal corresponding to the pressure of the supercharged intake air to the control device 70 .

An outflow side of the intake manifold 11E is connected to each cylinder of the internal combustion engine 10 .

The internal combustion engine 10 has a plurality of cylinders, and injectors 43A-43H are provided for each cylinder. Fuel is supplied to the injectors 43A-43H from the common rail 42 through fuel pipes, and the injectors 43A-43H are driven by control signals from the control device 70 to inject fuel into their respective cylinders.

Fuel is supplied to the common rail 42 from a fuel pressure regulating pump 41 that is driven based on a control signal from a control device 70 . Further, the common rail 42 is provided with fuel pressure detection means 23 (for example, a pressure sensor) for detecting the pressure of the fuel in the common rail 42 . The fuel pressure detection means 23 outputs a detection signal corresponding to the detected fuel pressure to the control device 70 . The control device 70 controls the fuel pressure adjustment pump 41 so that the fuel pressure based on the detection signal from the fuel pressure detection means 23 becomes the target fuel pressure.

The internal combustion engine 10 is provided with a rotation detection means 25 (for example, a rotation sensor), a coolant temperature detection means 24 (for example, a temperature sensor), an oil temperature detection means 22Y (for example, a temperature sensor), and the like. The rotation detection means 25 outputs a detection signal corresponding to the rotational speed of the crankshaft of the internal combustion engine 10 (that is, the engine rotational speed) to the control device 70 . The coolant temperature detection means 24 detects the temperature of the cooling coolant circulating in the internal combustion engine 10 and outputs a detection signal corresponding to the detected temperature to the control device 70 . The oil temperature detection means 22Y detects the temperature of lubricating oil circulating in the internal combustion engine 10 and outputs a detection signal corresponding to the detected temperature of the lubricating oil to the control device 70 .

The internal combustion engine 10 is connected to a blow-by gas pipe 13A that guides blow-by gas accumulated in the crankcase to an intake pipe 11B1 (intake path). The blow-by gas in the crankcase of the internal combustion engine 10 is drawn from the blow-by gas pipe 13A into the intake pipe 11B1. A blow-by gas path is formed from the inside of the crankcase to the connection point between the blow-by gas pipe 13A and the intake pipe 11B1, and the blow-by gas path is provided with a pressure detecting means 22P (for example, a pressure sensor). there is The details of the arrangement of the blow-by gas path and the pressure detection means 22P will be described later. The pressure detection means 22P outputs to the control device 70 a detection signal corresponding to the pressure of the blow-by gas in the blow-by gas path.

The inflow side of exhaust manifolds 12A1 and 12A2 is connected to the exhaust side of the internal combustion engine 10, the inflow side of an exhaust pipe 12B1 is connected to the outflow side of the exhaust manifold 12A1, and the inflow side of an exhaust pipe 12B2 is connected to the outflow side of the exhaust manifold 12A2. It is connected. The outflow side of the exhaust pipe 12B1 is connected to the inflow side of the turbine 31B of the first supercharger 31, and the outflow side of the exhaust pipe 12B2 is connected to the inflow side of the turbine 32B of the second supercharger 32. An exhaust switching valve 63 that opens and closes the exhaust pipe 12B2 based on a control signal from the control device 70 is provided in the exhaust pipe 12B2. An exhaust bypass pipe 12BB is connected to the exhaust pipes 12B1 and 12B2 to guide the exhaust in the exhaust pipe 12B2 to the exhaust pipe 12B1 when the exhaust switching valve 63 is closed.

The exhaust manifold 12A1 is also provided with exhaust pressure detection means 22F (for example, a pressure sensor) for detecting the pressure of the exhaust gas in the exhaust manifold 12A1. The exhaust pressure detection means 22F outputs a detection signal to the control device 70 according to the pressure of the exhaust gas in the exhaust manifold 12A1. Similarly, the exhaust manifold 12A2 is provided with exhaust pressure detection means 22G (for example, a pressure sensor) for detecting the pressure of the exhaust gas within the exhaust manifold 12A2. The exhaust pressure detection means 22G outputs a detection signal to the control device 70 according to the pressure of the exhaust gas in the exhaust manifold 12A2.

The inflow side of the exhaust pipe 12C2 is connected to the outflow side of the turbine 32B of the second supercharger 32, and the outflow side of the exhaust pipe 12C2 is connected in the middle of the exhaust pipe 12C1. The inflow side of the exhaust pipe 12C1 is connected to the outflow side of the turbine 31B of the first supercharger 31, and the outflow side of the exhaust pipe 12C1 is connected to the inflow side of the oxidation catalyst 51. The exhaust pipe 12</b>D, which is located downstream of the connecting point of the exhaust pipes 12</b>C 1 and 12</b>C 2 , is connected to the inflow side of the oxidation catalyst 51 . Further, the exhaust pipe 12C1 includes an exhaust pressure detection means 22B (for example, a pressure sensor) for detecting the pressure of the exhaust gas in the exhaust pipe 12C1, and an exhaust temperature detection means 26 (for example, a temperature sensor) for detecting the temperature of the exhaust gas in the exhaust pipe 12C1. etc. are provided. The exhaust pressure detection means 22B outputs a detection signal corresponding to the detected pressure to the control device 70, and the exhaust temperature detection means 26 outputs a detection signal to the control device 70 corresponding to the detected temperature.

The turbine 31B of the first turbocharger 31 is provided with a variable nozzle 31C capable of adjusting the flow velocity of the exhaust that rotationally drives the turbine 31B (adjusting the opening degree of the flow path leading the exhaust gas to the turbine 31B). ing. The variable nozzle 31C is operated by nozzle drive means 31D (for example, an electric motor) that operates according to a control signal from the control device 70. FIG. Further, the nozzle opening degree detection means 31E (for example, a rotation angle sensor) outputs a detection signal corresponding to the operating state of the nozzle driving means 31D (in this case, the rotation angle of the electric motor) according to the opening degree of the variable nozzle 31C. output to The control device 70 controls the nozzle drive means 31D so that the opening of the variable nozzle 31C obtained based on the detection signal from the nozzle opening detection means 31E becomes the target nozzle opening. The opening of the variable nozzle 31</b>C is adjusted by the control device 70 according to the operating state of the internal combustion engine 10 . The variable nozzle 32C of the turbine 32B of the second supercharger 32, the nozzle drive means 32D, and the nozzle opening degree detection means 32E are also the same, and descriptions thereof will be omitted.

The outflow side of the oxidation catalyst 51 is connected to the inflow side of the DPF 52 (particle collection filter). The oxidation catalyst 51 oxidizes and purifies HC (hydrocarbon) and CO (carbon monoxide) in the exhaust gas of the internal combustion engine 10 .

The outflow side of the DPF 52 is connected to the inflow side of the urea SCR 53 . DPF 52 collects particulates in the exhaust. Further, the DPF 52 is provided with differential pressure detecting means 22C (for example, a differential pressure sensor) for detecting the pressure difference between the inflow side and the outflow side of the DPF 52 . The differential pressure detection means 22C outputs a detection signal corresponding to the pressure difference between the inflow side and the outflow side of the DPF 52 to the control device 70 . The controller 70 can estimate the amount of fine particles deposited on the DPF 52 from the differential pressure based on the detection signal from the differential pressure detection means 22C.

The urea SCR 53 reduces and purifies NOx (nitrogen oxides) in exhaust gas using urea injected from a urea water addition valve (not shown).

The vehicle speed detection means 22H (for example, a vehicle speed sensor) is provided near wheels of the vehicle, for example, and outputs a detection signal corresponding to the rotation speed of the wheels to the control device 70 .

A parking brake detection means 22K (for example, a parking brake sensor) outputs a detection signal to the control device 70 according to whether the parking brake is ON or OFF.

The shift range detection means 22N (for example, a shift range sensor) outputs a detection signal corresponding to each position of the shift position (P, R, N, D, S, L range, etc.) of the shift lever of the vehicle to the control device 70. . The control device 70 can detect the position of the shift lever based on the detection signal from the shift range detection means 22N.

The foreign matter removing operation instruction input means 22S is an input switch that allows a user or the like to issue an instruction to start a foreign matter removing operation mode (to input an execution instruction).

The notification means 45 is a device for notifying the user of the state of the internal combustion engine 10, the state of the control device 70, etc., and is information output means such as a liquid crystal monitor, a lamp, a speaker, etc. In the present embodiment, the liquid crystal monitor An example will be described.

The accelerator pedal depression amount detection means 27 (for example, an accelerator pedal depression angle sensor) is provided on the accelerator pedal, and outputs a detection signal to the control device 70 according to the amount of depression of the accelerator pedal by the driver.

The control device 70 has at least a CPU 71 and a storage means 73 . The control device 70 detects the operating state of an internal combustion engine (internal combustion engine system) having a plurality of superchargers, and controls the amount of fuel injected into the cylinders of the internal combustion engine based on the detected operating state. The control device 70 (CPU 71) detects the operating state of the internal combustion engine 10 based on detection signals from various detection means including the above-described detection means, not limited to the above-described detection means and actuators shown in FIG. To detect. The control device 70 (CPU 71) controls various actuators including the injectors 43A to 43H, the intake bypass valve 61, the intake switching valve 62, the exhaust switching valve 63, the nozzle driving means 31D and 32D, and the fuel pressure adjusting pump 41. to control.

The control device 70 (CPU 71) includes an operating state detection portion 71A, a detection condition determination portion 71B, a first crankcase internal pressure acquisition portion 71C, an abnormality detection portion 71D, a redetection condition determination portion 71E, and a second crankcase internal pressure acquisition portion. 71F, an abnormality re-detection unit 71G, an abnormality determination determination unit 71H, a foreign matter removal operation execution unit 71I, a third crankcase internal pressure acquisition unit 71J, a foreign matter removal confirmation unit 71K, a foreign matter removal operation result notification unit 71L, and the like. , which will be discussed later. The storage means 73 is, for example, a storage device such as a Flash-ROM, and stores programs, data, etc. for executing processes described later.

The intake bypass valve 61, the intake switching valve 62, and the exhaust switching valve 63 are controlled to be in an open state or a closed state by the control device 70, and according to the operating state of the internal combustion engine 10, a plurality of turbochargers (in this case, two It is a switching means capable of switching the number of turbochargers to be operated out of one turbocharger.

● [Arrangement of blow-by gas path and pressure detection means 22P (Figs. 2 to 5)]
Next, the arrangement of the blow-by gas path and the pressure detecting means 22P for detecting the pressure of the blow-by gas (that is, the internal pressure of the crankcase) will be described with reference to FIG. FIG. 2 shows a cross-sectional view of the internal combustion engine 10. As shown in FIG. 3 shows an example of the appearance of the piston 10F and the piston rings 10G1 and 10G2, and FIG. 4 shows the state of the piston 10F arranged inside the cylinder 10B. 5 is an enlarged view of the V portion in FIG. 2. FIG.

As shown in FIG. 2, the internal combustion engine 10 has a cylinder head 10A, a cylinder 10B, a crankcase 10C, an oil pan 10D and the like. A gasket 10S is interposed between the cylinder 10B and the cylinder head 10A. An intake passage and an exhaust passage are formed in the cylinder head 10A, an intake valve is arranged in the intake passage, and an exhaust valve is arranged in the exhaust passage. Further, an injector is arranged in the cylinder head 10A so that the tip thereof reaches the inside of the cylinder 10B.

As shown in FIG. 2, one end of a gas passage 13C provided in the cylinder 10B and the crankcase 10C is connected inside the crankcase 10C. The other end of gas passage 13C is connected to one end of gas passage 13D provided in cylinder head 10A. The other end of the gas passage 13D is connected to one end of the blow-by gas pipe 13A. The other end of the blow-by gas pipe 13A is connected to the intake pipe 11B1 as shown in FIG. The gas passage 13C, the gas passage 13D, and the blow-by gas pipe 13A form a blow-by gas passage 13B that guides the blow-by gas in the crankcase to the intake passage of the internal combustion engine. The pressure detection means 22P is provided at a position where the pressure in the blow-by gas path 13B can be detected, and in the example shown in FIG. A pressure detection means 22P is provided at a detectable position. In this position the pressure sensing means 22P can sense static pressure in the overall crankcase.

The cylinder 10B has a cylindrical shape extending along a cylinder central axis 10BJ, which is the central axis of the cylinder 10B. A piston 10F that reciprocates along a cylinder center axis 10BJ is arranged in the cylinder 10B.

Piston 10F is connected to connecting rod 10M by piston pin 10H, and connecting rod 10M is connected to crankshaft 10E. A piston center axis 10FJ, which is the center axis of the piston 10F, substantially coincides with the cylinder center axis 10BJ. The outer diameter of the piston 10F is set smaller than the inner diameter of the cylinder 10B, and the outer peripheral surface of the piston 10F does not contact the inner wall of the cylinder 10B. the faces are in contact. A combustion chamber 10N is a space surrounded by the cylinder head 10A, the cylinder 10B, and the piston 10F.

As shown in FIG. 3, ring grooves 10F1 and 10F2 are formed along the circumferential direction on the outer peripheral surface of the piston 10F. Piston rings 10G1 and 10G2 are C-ring-shaped with gaps 10GA and 10GB, respectively, and are fitted into ring grooves 10F1 and 10F2 after being enlarged in diameter.

FIG. 4 shows a state in which the piston 10F is arranged inside the cylinder 10B. The piston 10F is arranged in the cylinder 10B with the piston rings 10G1 and 10G2 in a reduced diameter state. Therefore, in the cylinder 10B, the piston rings 10G1 and 10G2 are restored so that their diameters are enlarged from the diameter-reduced state. As a result, as shown in FIGS. 2 and 5, the piston rings 10G1 and 10G2 come into contact with the inner wall 10BN (see FIG. 5) of the cylinder 10B, sealing the combustion chamber 10N together with the lubricating oil film.

Incidentally, as shown in FIG. 4, the combustion chamber 10N and the inside of the crankcase 10C communicate with each other through joint gaps 10GA and 10GB of the piston rings 10G1 and 10G2. Further, as shown in FIG. 5, the piston rings 10G1 and 10G2 are restored in the radially expanding direction within the ring grooves 10F1 and 10F2 of the piston 10F. The combustion chamber communicates with the inside of the crankcase through the gap. Through these connections, high-temperature, high-pressure gas generated in the combustion chamber during the combustion process leaks from the combustion chamber 10N (see FIG. 4) into the crankcase and becomes blow-by gas.

In addition, part of the lubricating oil is carbonized by the combustion process and becomes deposits (foreign matter). For example, deposits (foreign matter) formed on the inner wall of the cylinder 10B shown in FIG. 2 are scraped off by the piston rings 10G1 and 10G2. However, deposits (foreign matter) that have entered the gaps between the piston rings 10G1, 10G2 and the ring grooves 10F1, 10F2 shown in FIG. 5 may accumulate without being scraped off.

When the piston 10F reciprocates, the piston rings 10G1 and 10G2 shown in FIG. 4 may turn little by little with respect to the piston 10F. For example, in FIG. 4, when deposits (foreign matter) are accumulated at positions DP1 and DP2, which are gaps between the piston rings 10G1 and 10G2 and the ring grooves, the position DP1 of the deposits (foreign matter) and the gap between the piston ring 10G1 When the position of 10GA matches, the state of communication between the combustion chamber 10N and the inside of the crankcase changes, and the amount of blow-by gas changes. Similarly, when the position DP2 of the deposit (foreign matter) matches the position of the joint gap 10GB of the piston ring 10G2, the state of communication between the combustion chamber 10N and the inside of the crankcase changes, and the amount of blow-by gas changes. This changes the internal pressure of the crankcase.

In addition, if deposits (foreign matter) accumulate in the gaps between the piston rings 10G1 and 10G2 and the ring grooves 10F1 and 10F2, the piston rings 10G1 and 10G2 will adhere to the ring grooves 10F1 and 10F2, causing the piston rings 10G1 and 10G2 to become stuck. It inhibits the diameter reduction and diameter expansion of the If the diameters of the piston rings 10G1 and 10G2 cannot be expanded or contracted, the sealing performance of the combustion chamber may deteriorate. When the sealing performance of the combustion chamber deteriorates, the amount of blow-by gas leaking from the combustion chamber 10N into the crankcase changes, and the internal pressure of the crankcase changes.

A control device 70 (corresponding to a control device for an internal combustion engine) described in the present embodiment determines whether or not foreign matter (deposits) are deposited around the piston rings, as will be described later, based on the above-described crankcase internal pressure. to detect

● [Processing procedure of the overall process of the control device 70 in the first embodiment (FIG. 6)]
Next, processing procedures and the like of the first embodiment of the control device 70 will be described with reference to FIGS. 6 to 23. FIG. In the first embodiment, the blow-by gas internal pressure is detected for a first predetermined time, and an abnormality is detected (determined to be foreign matter) when a "step" occurs in the detected blow-by gas internal pressure. When it is determined that there is a foreign substance, a foreign substance removal operation mode for removing the foreign substance is executed, and whether or not the foreign substance has been removed is also determined as a result of the executed foreign substance removal operation mode.

The overall process shown in FIG. 6 is activated, for example, at predetermined time intervals (for example, intervals of several [ms] to several tens [ms]). proceed. Note that when the control device 70 is activated, the foreign matter detection end flag, the (final) foreign matter present flag, the foreign matter removal completed flag, the foreign matter removal in progress flag, the post-removal confirmation flag, the post-removal confirmation flag, the removal Various flags such as the completion flag are set to OFF as an initial value.

In step S010, as input signal processing, the control device 70 acquires and stores physical quantities (various physical quantities indicating the operating state of the internal combustion engine 10) based on detection signals from various detection means, and proceeds to step S015. Proceed with processing. For example, current accelerator pedal depression amount, vehicle speed, parking switch state, neutral switch state, foreign object removal operation instruction input means state, intake air flow rate, atmospheric pressure, intake air temperature, supercharging pressure, coolant temperature, lubricating oil temperature, Injected fuel amount, injection time width, fuel pressure, internal combustion engine speed, exhaust pressure in exhaust manifold 12A1, exhaust pressure in exhaust manifold 12A2, turbine downstream exhaust pressure, exhaust temperature, first supercharger/second supercharger The machine operation state, the opening degree of the variable nozzle of the first turbocharger, the opening degree of the variable nozzle of the second turbocharger, the differential pressure of the DPF, and the like are acquired. Then, the control device 70 presents the present accelerator pedal depression amount, present vehicle speed, present parking switch state, present neutral switch state, present foreign object removal operation instruction input means state, present intake air flow rate, present atmospheric pressure, present intake air temperature, present supercharging. pressure, coolant temperature this time, lubricating oil temperature this time, fuel amount this time, injection time width this time, fuel pressure this time, rotation speed this time, exhaust pressure in exhaust manifold (12A1) this time, exhaust pressure in exhaust manifold (12A2) this time, turbine this time Stored as downstream exhaust pressure, current exhaust temperature, current turbocharger operation status (1 turbo operation or 2 turbo operation), current 1st turbocharger nozzle opening, current 2nd turbocharger nozzle opening, current differential pressure, etc. do. Note that the physical quantities and the like to be stored are not limited to these, and the control device 70 acquires and stores various physical quantities and the like based on the operating state of the internal combustion engine.

The control device 70 (CPU 71) executing the process of step S010 corresponds to the operating state detector 71A (see FIG. 1) that detects the operating state of the internal combustion engine.

In step S015, the controller 70 determines whether or not the foreign object detection end flag is ON, and if the foreign object detection end flag is ON (Yes), the process proceeds to step S030, and If not (No), the process proceeds to step S020. Note that the foreign object detection end flag is a flag that is turned ON when the foreign object detection processing in step SA100 (foreign object detection processing) described later is completed.

When proceeding to step S020, control device 70 executes process SA100 (foreign object detection process) and advances the process to step S025. Details of the process SA100 (foreign matter detection process) will be described later.

In step S025, the controller 70 determines whether or not the foreign object detection end flag is ON. If the foreign object detection end flag is ON (Yes), the process proceeds to step S030, and If not (No), the process shown in FIG. 6 is terminated.

When the process proceeds to step S030, the control device 70 determines whether or not the (final) foreign object flag=ON, and if the (final) foreign object flag=ON (Yes), the process proceeds to step S035B. If the (final) foreign object flag is not ON (No), the process proceeds to step S035A.

When the process proceeds to step S035A, the control device 70 outputs a control signal to the notification means 45 (see FIG. 1) to stop the display if the notification such as "foreign object present" is output. Then, the processing shown in FIG. 6 ends.

When the process proceeds to step S035B, the control device 70 outputs a control signal for outputting a notification such as "foreign object present" to the notification means 45 (see FIG. 1), and advances the process to step S040. In addition, the control device 70 notifies the user that "there is a foreign object" or the like, and "parks in a safe place and presses the foreign object removal operation instruction input means (reference numeral 22S in FIG. 1) to operate the foreign object removal operation (it will take about X [minutes]. )”, etc., a control signal is output to the notification means 45 so as to cause the notification means 45 to output.

In step S040, the controller 70 determines whether or not the foreign matter removal flag is ON. If the foreign matter removal flag is ON (Yes), the process proceeds to step S060. If the flag is not ON (No), the process proceeds to step S045. The foreign matter removal completion flag is a flag that is turned ON when the processing for removing foreign matter in step SB100 (foreign matter removal processing), which will be described later, is completed.

When the process proceeds to step S045, the control device 70 determines whether or not there is a foreign matter removal instruction, and if there is a foreign matter removal instruction (Yes) (the foreign matter removal operation instruction input means 22S (see FIG. 1) is operated). If there is no foreign matter removal instruction (No) (if the foreign matter removal operation instruction input means 22S (see FIG. 1) is not operated), the processing shown in FIG. 6 is terminated. .

When the process proceeds to step S050, the control device 70 executes process SB100 (foreign matter removal process) and proceeds to step S055. Details of the process SB100 (foreign matter removal process) will be described later.

In step S055, the control device 70 determines whether or not the foreign matter removal flag is ON. If the flag is not ON (No), the processing shown in FIG. 6 is terminated.

When the process proceeds to step S060, the control device 70 sets the foreign matter removal flag to OFF, and proceeds to step S065. The foreign matter removal in-progress flag is a flag that is set to ON or OFF in step SB100 (foreign matter removal processing) of step S050, and is a flag that is set to ON while the foreign matter removal operation mode is being executed.

In step S065, the control device 70 determines whether or not the post-removal confirmation flag is ON. If the post-removal confirmation flag is ON (Yes), the process proceeds to step S080, and the post-removal confirmation flag is ON. If the flag is not ON (No), the process proceeds to step S070. The post-removal confirmation flag is turned ON when the process for confirming whether or not the foreign matter has been removed as a result of executing the foreign matter removal operation mode in step SC100 (post-removal confirmation processing), which will be described later, is completed. flag.

When the process proceeds to step S070, the control device 70 executes process SC100 (post-removal confirmation process) and proceeds to step S075. Details of the process SC100 (post-removal confirmation process) will be described later.

In step S075, the control device 70 determines whether or not the post-removal confirmation flag is ON. If the post-removal confirmation flag is ON (Yes), the process proceeds to step S080, and the post-removal confirmation flag is ON. If the flag is not ON (No), the processing shown in FIG. 6 is terminated.

When the process proceeds to step S080, the control device 70 sets the post-removal confirmation flag to OFF, and proceeds to step S085. The post-removal confirmation flag is a flag that is set to ON in the process SC100 (post-removal confirmation process) of step S070, and is confirming whether or not the foreign matter has been removed as a result of executing the foreign matter removal operation mode. is a flag that is turned ON when

In step S085, the control device 70 determines whether or not the removal completion flag is ON. If the removal completion flag is ON (Yes), the process proceeds to step S090A, and if the removal completion flag is not ON ( No) advances the process to step S090B. The removal completion flag is a flag that is turned ON when it is confirmed that the foreign matter has been removed as a result of executing the foreign matter removal operation mode in the processing SC100 (post-removal confirmation processing) of step S070.

When the process proceeds to step S090A, the control device 70 outputs a control signal to the notification means 45 (see FIG. 1) to output a notification such as "It was confirmed that the foreign matter was removed." , the process shown in FIG. 6 ends.

When the process proceeds to step S090B, the control device 70 informs the notification means 45 (see FIG. 1), "I tried to remove the foreign object, but I could not remove it. Please bring it in." or the like is output, and the process shown in FIG. 6 is terminated.

The control device 70 (CPU 71) executing the processing of steps S085 and S090A (as a result of executing the foreign matter removal operation mode) moves around the piston ring of the internal combustion engine in the foreign matter removal confirmation section 71K (see FIG. 1). corresponds to the foreign matter removal operation result notification unit 71L (see FIG. 1), which notifies that the removal of the foreign matter has been completed using the notification means when it is detected that there is no accumulation of foreign matter (the foreign matter has been removed). ing. Further, the control device 70 (CPU 71) executing the processes of steps S085 and S090B determines (as a result of executing the foreign matter removal operation mode) that the piston ring of the internal combustion engine is A foreign matter removal operation result reporting unit 71L (Fig. 1 reference).

● [SA100: Foreign matter detection process (Fig. 7)]
Next, details of the process SA100 (foreign object detection process) in step S020 in the flowchart of FIG. 6 will be described with reference to FIG. After executing process SA100 in step S020 of FIG. 6, control device 70 advances the process to step SA110 shown in FIG.

When the process proceeds to step SA110, the controller 70 determines whether or not the foreign object detection (provisional) end flag=ON, and if the foreign object detection (provisional) end flag=ON (Yes), step SA155. If the foreign matter detection (temporary) end flag is not ON (No), the process proceeds to step SA115. In process SA100, control device 70 performs foreign object detection (abnormality detection) twice just in case, and turns on the foreign object detection (provisional) end flag when the first foreign object detection (foreign object detection) is completed. do.

When the process proceeds to step SA115, the control device 70 determines whether or not the operating state of the internal combustion engine satisfies (establishes) the first detection condition, and satisfies (establishes) the first detection condition. If so (Yes), the process proceeds to step SA120, and if the first detection condition is not satisfied (established) (No), the process proceeds to step SA125B. Note that the first detection condition is, for example, "the internal combustion engine is in a warm-up state" and "the amount of fluctuation in the load of the internal combustion engine (the load obtained based on the rotation speed and the fuel injection amount) is within the allowable load fluctuation range, Alternatively, the condition includes "the fluctuation amount of the rotation speed of the internal combustion engine is within the allowable rotation speed fluctuation range".

Based on the detected operating state of the internal combustion engine, the control device 70 (CPU 71) executing the process of step SA115 determines whether the amount of fluctuation in the load of the internal combustion engine is within the allowable load fluctuation range or the amount of fluctuation in the rotational speed of the internal combustion engine. is within the permissible rotation speed fluctuation range and the internal combustion engine is after warm-up (first detection condition) is satisfied (established), the detection condition determination unit 71B ( 1).

When the process proceeds to step SA120, the control device 70 determines whether or not the timer is running, and if the timer is running (Yes), the process proceeds to step SA130, and the timer is not running. If not (No), the process proceeds to step SA125A. Note that the timer in this case measures the elapsed time after the first detection condition in step SA115 is satisfied (established).

When the process proceeds to step SA125A, control device 70 initializes (resets to 0) the timer and activates the timer (starts measuring the elapsed time). Control device 70 also initializes the value of variable i to "1" and advances the process to step SA130. When the first detection condition is satisfied (established), the control device 70 executes the process SA100 at predetermined time intervals for the first predetermined time in subsequent processes to measure the crankcase internal pressure [i]. memorize. In the subsequent processing, for example, when the crankcase internal pressure is measured 100 times during the first predetermined time period, the control device 70 stores the crankcase internal pressure [1] to the crankcase internal pressure [100].

When the process proceeds to step SA125B, control device 70 stops the timer (stops measuring the elapsed time) and ends the process shown in FIG. After finishing the process of FIG. 7, the control device 70 advances the process to step S025 shown in FIG.

When the process proceeds to step SA130, the control device 70 obtains the crankcase internal pressure based on the detection signal from the pressure detection means 22P (see FIGS. 1 and 2), and uses the value of the variable i to The case internal pressure [i] is stored. The control device 70 also counts up the value of the variable i in preparation for the crankcase internal pressure to be acquired and stored next. Then, control device 70 advances the process to step SA135.

The control device 70 (CPU 71) executing the process of step SA130 detects the pressure in the crankcase of the internal combustion engine, which is one of the operating conditions of the internal combustion engine (when the detection condition (first detection condition) is satisfied). corresponds to the first crankcase internal pressure acquisition unit 71C (see FIG. 1) that acquires the crankcase internal pressure for a first predetermined period of time.

At step SA135, the control device 70 determines whether or not the elapsed time measured by the timer is equal to or longer than the first predetermined time. If it is less than one predetermined time (No), the process shown in FIG. 7 is terminated. After finishing the process of FIG. 7, the control device 70 advances the process to step S025 shown in FIG. Note that the value of the first predetermined time is appropriately set, and is, for example, about several tens [sec] to several [min].

When the process proceeds to step SA140, the control device 70 stops the operation of the timer (stops measuring the elapsed time) and proceeds to step SA145.

In step SA145, control device 70 executes process SA200 (abnormality detection process) and advances the process to step SA150. Details of the processing SA200 (abnormality detection processing) will be described later.

In step SA150, control device 70 sets the foreign matter detection (provisional) end flag to ON, and advances the process to step SA155. Since the foreign object detection (provisional) end flag is set to ON, the control device 70 recognizes that the first foreign object detection (abnormality detection) executed twice in steps SA115 to SA145 has ended. can be done.

When the process proceeds to step SA155, the control device 70 determines whether or not the (temporary) abnormality flag is ON, and if the (temporary) abnormality flag is ON (Yes), the process proceeds to step SA160. If the (temporary) abnormality flag is not ON (No), the process proceeds to step SA195. The (temporary) abnormality flag is a flag that is turned ON when an abnormality is detected in the process SA200 (step SA145), which is the first foreign matter detection (abnormality detection) process.

When the process proceeds to step SA160, the control device 70 determines whether or not the operating state of the internal combustion engine satisfies the second detection condition, and if the second detection condition is satisfied (Yes), step The process proceeds to SA165, and if the second detection condition is not satisfied (No), the process proceeds to step SA170B. The second detection condition is, for example, a condition including "the operating state of the internal combustion engine is the idling state".

The control device 70 (CPU 71) executing the process of step SA160 detects, in the abnormality detection section (corresponding to process SA200), that there is accumulation of foreign matter around the piston ring of the internal combustion engine ((temporary ) when the abnormality flag is ON), a re-detection condition for determining whether or not a re-detection condition (second detection condition) including that the operating state of the internal combustion engine is in an idling state (predetermined operating state) is satisfied. It corresponds to the determination unit 71E (see FIG. 1). The "predetermined operating state" is not limited to the idling state, and can be set to various operating states.

When the process proceeds to step SA165, the control device 70 determines whether or not the timer is running, and if the timer is running (Yes), the process proceeds to step SA175 and the timer is not running. In the case (No), the process proceeds to step SA170A. Note that the timer in this case measures the elapsed time after the second detection condition in step SA160 is satisfied.

When the process proceeds to step SA170A, control device 70 initializes (resets to 0) the timer and activates the timer (starts measuring the elapsed time). The control device 70 also initializes the value of the variable i to "1". When the second detection condition is satisfied, the control device 70 executes the process SA100 at predetermined time intervals for a second predetermined period of time in subsequent processes to measure and store the crankcase internal pressure [i]. . In the subsequent processing, for example, when the crankcase internal pressure is measured 100 times during the second predetermined time period, the control device 70 stores the crankcase internal pressure [1] to the crankcase internal pressure [100].

When the process proceeds to step SA170B, control device 70 stops the timer (stops measuring the elapsed time) and ends the process shown in FIG. After finishing the process of FIG. 7, the control device 70 advances the process to step S025 shown in FIG.

When the process proceeds to step SA175, the control device 70 acquires the crankcase internal pressure based on the detection signal from the pressure detection means 22P (see FIGS. 1 and 2), and uses the value of the variable i to The case internal pressure [i] is stored. The control device 70 also counts up the value of the variable i in preparation for the crankcase internal pressure to be acquired and stored next. Then, control device 70 advances the process to step SA180.

The control device 70 (CPU 71) executing the processing of step SA175 detects that foreign matter has accumulated around the piston ring of the internal combustion engine in the abnormality detection section 71D (see FIG. 1) (and A second crankcase internal pressure acquisition unit 71F (see FIG. 1) that acquires the crankcase internal pressure, which is the pressure within the crankcase of the internal combustion engine, for a second predetermined period of time when the detection condition (second detection condition) is satisfied. is equivalent to

At step SA180, the control device 70 determines whether or not the elapsed time measured by the timer is equal to or longer than the second predetermined time. If it is less than 2 predetermined times (No), the process shown in FIG. 7 is terminated. After finishing the process of FIG. 7, the control device 70 advances the process to step S025 shown in FIG. Note that the value of the second predetermined time is appropriately set, and is, for example, about several tens [sec] to several [min].

When the process proceeds to step SA185, control device 70 stops the operation of the timer (stops measuring the elapsed time) and proceeds to step SA190.

In step SA190, control device 70 executes process SA300 (abnormality re-detection process) and advances the process to step SA195. Details of the processing SA300 (abnormality re-detection processing) will be described later.

At step SA195, control device 70 sets the foreign object detection end flag to ON, and ends the processing shown in FIG. After finishing the process of FIG. 7, the control device 70 advances the process to step S025 shown in FIG. Control device 70 can recognize that foreign matter detection (abnormality detection) executed twice in process SA100 has ended by setting the foreign matter detection end flag to ON.

● [SA200: Abnormality detection processing (Fig. 8, Fig. 9)]
Next, details of the process SA200 (abnormality detection process) of step SA145 in the flowchart of FIG. 7 will be described with reference to FIG. After executing process SA200 in step SA145 of FIG. 7, control device 70 advances the process to step SA210 shown in FIG.

When the process proceeds to step SA210, the control device 70 stores the plurality of stored crankcase internal pressures [1] to [n] as data having a pressure difference within ±ΔP between the front and rear and k or more continuous data. The data are classified into groups Ad, Bd, . . . , and the process proceeds to step SA215. Note that the values of ΔP and k are appropriately set. For example, when detecting the crankcase internal pressure [1] to crankcase internal pressure [n] during the first predetermined time shown in FIG. ] are classified into data groups Ad, Bd, and Cd, which are data groups in which the pressure difference before and after is within ±ΔP and in which k or more are consecutive.

In step SA215, control device 70 calculates the average pressure of each data group (data groups Ad, Bd, and Cd in the example of FIG. 9), and advances the process to step SA220. In the example of FIG. 9, the control device 70 calculates the average pressure Avp(A) of the data group Ad, the average pressure Avp(B) of the data group Bd, and the average pressure Avp(C) of the data group Cd.

At step SA220, the control device 70 determines that at least one of the differences between the average pressures of adjacent data groups (corresponding to a pressure step that is a step-like fluctuation amount) is equal to or greater than the first abnormal step pressure set as the threshold for abnormality determination. If at least one is equal to or higher than the first abnormal step pressure (Yes), the process proceeds to Step SA225A; otherwise (No), the process proceeds to Step SA225B. In the example of FIG. 9, the control device 70 calculates |average pressure Avp(A) of data group Ad−average pressure Avp(B) of data group Bd|=|Dp(AB)| and |average pressure of data group Bd It is determined whether or not at least one of Avp(B)-average pressure Avp(C)|=|Dp(BC)| of data group Cd is greater than or equal to the first abnormal step pressure. An appropriate value for the first abnormal step pressure is selected through experiments, simulations, or the like using an actual vehicle.

When the process proceeds to step SA225A, control device 70 sets the (provisional) abnormality flag to ON, and ends the process shown in FIG. After completing the process of FIG. 8, control device 70 advances the process to step SA150 shown in FIG.

When the process proceeds to step SA225B, control device 70 sets the (provisional) abnormality flag to OFF, and ends the process shown in FIG. After completing the process of FIG. 8, control device 70 advances the process to step SA150 shown in FIG.

The control device 70 (CPU 71) executing the processes of steps SA210 to SA225A and SA225B of the process SA200 detects a pressure difference, which is a step-like fluctuation amount of the obtained crankcase internal pressure, as a threshold for abnormality determination. Based on whether or not there is a pressure step greater than the set abnormal step pressure (first abnormal step pressure) (or a pressure step greater than or equal to the abnormal step pressure), it is determined whether foreign matter is deposited around the piston ring of the internal combustion engine. It corresponds to the abnormality detection unit 71D (see FIG. 1). As described above, the control device 70 sets the (temporary) abnormality flag to ON when it is determined that there is an accumulation of foreign matter.

● [SA300: Abnormality re-detection process (Fig. 10)]
Next, details of the process SA300 (abnormality re-detection process) of step SA190 in the flowchart of FIG. 7 will be described with reference to FIG. After executing process SA300 in step SA190 of FIG. 7, control device 70 advances the process to step SA310 shown in FIG.

When the process proceeds to step SA310, the control device 70 stores the plurality of stored crankcase internal pressures [1] to [m] as data having a pressure difference within ±ΔP between the front and rear and k or more continuous data. The data are classified into groups Ad, Bd, . . . , and the process proceeds to step SA315. Note that the values of ΔP and k are appropriately set. Note that this process is the same as the process of step SA210 shown in FIG. 8, so the description is omitted.

In step SA315, control device 70 calculates the average pressure of each data group and advances the process to step SA320. Note that this process is the same as the process of step SA215 shown in FIG. 8, so description thereof will be omitted.

At step SA320, the control device 70 determines that at least one of the differences between the average pressures of adjacent data groups (corresponding to a pressure step that is a step-like variation amount) is equal to or greater than the second abnormal step pressure set as the threshold for abnormality determination. If at least one is equal to or higher than the second abnormal step pressure (Yes), the process proceeds to Step SA325A; otherwise (No), the process proceeds to Step SA325B. Note that this process is the same as the process of step SA220 shown in FIG. 8, so description thereof will be omitted. An appropriate value for the second abnormal bump pressure is selected through experiments, simulations, or the like using an actual vehicle.

When the process proceeds to step SA325A, control device 70 sets the (final) abnormality flag to ON, and ends the process shown in FIG. 10, control device 70 advances the process to step SA195 shown in FIG.

When the process proceeds to step SA325B, control device 70 sets the (final) abnormality flag to OFF, and ends the process shown in FIG. 10, control device 70 advances the process to step SA195 shown in FIG.

The control device 70 (CPU 71) executing the process SA300 performs the processing of the abnormality detection section 71D (see FIG. 1) in correspondence with the acquisition of the crankcase internal pressure by the second crankcase internal pressure acquisition section 71F (see FIG. 1). It corresponds to the abnormality re-detection section 71G that executes (performs abnormality determination similar to that of the abnormality detection section 71D). The control device 70 determines an abnormality ((temporary) abnormality flag=ON) in the abnormality detection section 71D that is the first abnormality detection (foreign object detection), and furthermore, the second abnormality redetection (foreign object redetection). If an abnormality is determined in , the abnormality is confirmed (the (final) abnormality flag is set to ON).

Further, the control device 70 (CPU 71) executing the process SA300 causes the abnormality re-detection section 71G (see FIG. 1) to re-start the internal combustion engine. When it is detected that there is accumulation of foreign matter around the piston ring, it is determined that there is accumulation of foreign matter around the piston ring of the internal combustion engine ((final) abnormality flag = ON), abnormality confirmation It corresponds to the determination section 71H (see FIG. 1).

● [SB100: foreign matter removal process (Fig. 11)]
Next, details of the process SB100 (foreign matter removal process) in step S050 in the flowchart of FIG. 6 will be described with reference to FIG. After executing process SB100 in step S050 of FIG. 6, control device 70 advances the process to step SB110 shown in FIG. The set counter Cset and the first to fifth repetition counters C1 to C5 are set to "0" as initial values, and various flags are set to "OFF" as initial values.

The control device 70 (CPU 71) executing the processing of step SB100 (foreign matter removal processing) receives an instruction to start the foreign matter removal operation mode from the foreign matter removal operation instruction input means (and satisfies the removal conditions). ) corresponds to the foreign matter removal operation executing section 71I (see FIG. 1) capable of (executing) a foreign matter removal operation mode for removing foreign matter deposited around the piston ring of the internal combustion engine.

During execution of the process SB100 (foreign matter removal process) shown in FIG. 11, the foreign matter removal in-progress flag is set to ON (from step SB185A in FIG. 11). When the foreign matter removal execution flag is set to ON, the turbo switching mode is fixed to the 2-turbo mode as shown in FIG. is switched to the removed injection amount Qremv. Further, as shown in FIG. 21, the final variable nozzle closing degree, which is the variable nozzle closing degree that is finally output, is switched to the removal variable nozzle closing degree Vremv, and as shown in FIG. The final injection timing, which is the timing, is switched to the removal injection timing Aremv. Details of the processing in FIGS. 19 to 22 will be described later.

When the process proceeds to step SB110, the control device 70 determines whether or not the removal condition, which is the execution condition of the foreign matter removing operation mode for removing the foreign matter, is satisfied based on the operating state of the internal combustion engine. If the removal condition is satisfied (Yes), the process proceeds to step SB115, and if the removal condition is not satisfied (No), the process proceeds to step SB190. The removal condition is, for example, a condition including "the vehicle is in a stopped state". For example, based on the detection signals from the parking brake detection means 22K, the shift range detection means 22N, and the vehicle speed detection means 22H shown in FIG. When "P" and vehicle speed=0 [km/h] are detected, it is determined that "the vehicle is in a stopped state." Further, as removal conditions, the lubricating oil temperature detected using the oil temperature detection means 22Y (see FIG. 1) is 90 [° C.] or more, and the coolant temperature detected using the coolant temperature detection means 24 (see FIG. 1) is 90 [ °C] and above may be added.

When the process proceeds to step SB115, the control device 70 determines whether or not the value of the set counter Cset is equal to or greater than the predetermined number of sets. If it is less than the predetermined set number (No), the process proceeds to step SB120. It should be noted that the set counter is executed in the foreign object removal operation mode (to be described later) fuel sweep increase/decrease control (1), fuel sweep increase/decrease control (2), boost pressure/exhaust pressure step increase/decrease control, fuel injection timing step advance. When the retardation control and the fuel step increase/decrease control have been executed, it is determined that one set of foreign matter removal operation is completed, and the set counter Cset is counted up. For example, when the value of the predetermined number of times is set to "5", the control device 70 controls (described later) fuel sweep increase/decrease control (1), fuel sweep increase/decrease control (2), boost pressure/exhaust pressure step increase/decrease Control, fuel injection timing step advance/retard control, and fuel step increase/decrease control are repeated five times. Note that the value of the predetermined set number is not limited to "5".

When the process proceeds to step SB190, control device 70 stops the timer (stops measuring the elapsed time) and proceeds to step SB185B.

When the process proceeds to step SB120, the control device 70 determines whether or not the first repetition counter C1 is equal to or greater than the first number of repetitions. , and if it is less than the first number of repetitions (No), the process proceeds to step SB125. It should be noted that the first repetition counter C1 gradually increases the fuel injection amount from QL1 to QH1 for a relatively long period of time from time T10 to time T20 in the operation waveform of the foreign object removal operation mode shown in FIG. It shows the number of times the fuel sweep increase/decrease control (1) in step SB125, which slowly reduces the amount from QH1 to QL1 in a relatively long period of time, is repeated. For example, when the first number of repetitions is set to "10", the control device 70 gradually increases the fuel injection amount from QL1 to QH1, and then gradually decreases the fuel injection amount from QH1 to QL1 ( The fuel sweep increase/decrease control (1)) is repeated ten times. Note that the first number of repetitions is not limited to "10".

When the process proceeds to step SB125, control device 70 executes process SB200 (fuel sweep increase/decrease control (1)) and proceeds to step SB185A. Details of the process SB200 (fuel sweep increase/decrease control (1)) will be described later.

When the process proceeds to step SB130, the control device 70 determines whether or not the second repetition counter C2 is equal to or greater than the second number of repetitions, and if it is equal to or greater than the second number of repetitions (Yes), the process proceeds to step SB140. , and if it is less than the second repetition number (No), the process proceeds to step SB135. Note that the second repetition counter C2 increases the fuel injection amount from QL1 to QH1 in a relatively short period of time from time T20 to time T30 in the operation waveform of the foreign object removal operation mode shown in FIG. It shows the number of repetitions of the fuel sweep increase/decrease control (2) in step SB135, in which the amount is rapidly decreased from QH1 to QL1 in a relatively short time. For example, when the second number of repetitions is set to "10", the control device 70 rapidly increases the fuel injection amount from QL1 to QH1, and then performs control ( The fuel sweep increase/decrease control (2)) is repeated ten times. Note that the second number of repetitions is not limited to "10".

When the process proceeds to step SB135, control device 70 executes process SB300 (fuel sweep increase/decrease control (2)) and proceeds to step SB185A. Details of the process SB300 (fuel sweep increase/decrease control (2)) will be described later.

When the process proceeds to step SB140, the control device 70 determines whether or not the third repetition counter C3 is equal to or greater than the third number of repetitions. , and if it is less than the third repetition number (No), the process proceeds to step SB145. Note that the third repetition counter C3 sets the nozzle closing degree of the variable nozzles 31C and 32C (see FIG. 1) to Vmid-->Vinc-- from time T30 to time T40 in the operation waveform of the foreign matter removal operation mode shown in FIG. >Vdec stepwise, the number of times the boost pressure/exhaust pressure step increase/decrease control in step SB145 has been repeated. For example, when the third number of repetitions is set to "3", the control device 70 performs control (supercharge pressure/exhaust pressure step increase/decrease control) is repeated three times. Note that the third number of repetitions is not limited to "3".

When the process proceeds to step SB145, the control device 70 executes process SB400 (boost pressure/exhaust pressure step increase/decrease control) and proceeds to step SB185A. Details of the process SB400 (boost pressure/exhaust pressure step increase/decrease control) will be described later.

When the process proceeds to step SB150, the control device 70 determines whether or not the fourth repetition counter C4 is equal to or greater than the fourth number of repetitions. , and if it is less than the fourth iteration count (No), the process proceeds to step SB155. It should be noted that the fourth repetition counter C4 changes the fuel injection timing stepwise from time T40 to time T50 in the operation waveform of the foreign object removal operation mode shown in FIG. This indicates the number of times the fuel injection timing step advance/retard control of step SB155 has been repeated. For example, when the fourth number of repetitions is set to "3", the control device 70 performs control to change the fuel injection timing in steps of Amid --> Ainc --> Adec (fuel injection timing step advance angle・Retard control) is repeated three times. Note that the fourth number of repetitions is not limited to "3".

When the process proceeds to step SB155, control device 70 executes process SB500 (fuel injection timing step advance/retard control) and advances the process to step SB185A. Details of the process SB500 (fuel injection timing step advance/retard control) will be described later.

When the process proceeds to step SB160, the control device 70 determines whether or not the fifth repetition counter C5 is equal to or greater than the fifth number of repetitions. , and if it is less than the fifth iteration number (No), the process proceeds to step SB165. It should be noted that the fifth repetition counter C5 changes the fuel injection amount in a stepwise manner from Qmid-->Qinc-->Qdec from time T50 to time T60 in the operation waveform of the foreign object removal operation mode shown in FIG. Indicates the number of times the fuel step increase/decrease control of SB165 has been repeated. For example, when the fifth number of repetitions is set to "3", the control device 70 performs control (fuel step increase/decrease control) to change the fuel injection amount in a stepwise manner from Qmid-->Qinc-->Qdec to 3 times. repeat times. Note that the fifth repetition number is not limited to "3".

When the process proceeds to step SB165, control device 70 executes process SB600 (fuel step increase/decrease control) and proceeds to step SB185A. Details of the process SB600 (fuel step increase/decrease control) will be described later.

When the process proceeds to step SB170, the control device 70 determines that one set of the foreign matter removing operation from time T10 to time T60 in FIG. 5 Repeat counter C5 is initialized to "0" and the process proceeds to step SB175.

At step SB175, the control device 70 determines whether or not the set counter Cset is equal to or greater than the predetermined number of sets. If not (No), the process proceeds to step SB185B.

When the process proceeds to step SB180, control device 70 sets the foreign matter removal completion flag=ON, and proceeds to step SB185B. The foreign matter removal completion flag is a flag indicating that execution of the process SB100 (foreign matter removal process) in step S050 in FIG. , is a flag indicating that it has been executed a predetermined number of times (for example, 5 times).

When the process has proceeded to step SB185B, control device 70 sets the foreign matter removal in-progress flag=OFF, and ends the process shown in FIG. After completing the process of FIG. 11, the control device 70 advances the process to step S055 shown in FIG.

● [SB200: Fuel sweep increase/decrease control (1) (Fig. 12)]
Next, details of the process SB200 (fuel sweep increase/decrease control (1)) of step SB125 in the flowchart of FIG. 11 will be described with reference to FIG. After executing process SB200 in step SB125 of FIG. 11, control device 70 advances the process to step SB210 shown in FIG. Fuel sweep increase/decrease control (1) is a control in which the fuel injection amount is gradually increased from QL1 to QH1 and then gradually decreased from QH1 to QL1, as shown from time T10 to time T20 in FIG. is. In the fuel sweep increase/decrease control (1), the fuel injection amount is gradually increased for a predetermined period to promote moistening of foreign matter around the piston ring, and the fuel injection amount is gradually decreased for the predetermined period. This raises the combustion temperature and promotes drying of the moistened foreign matter. By repeating this for a predetermined number of times (the first number of repetitions), the exfoliation of foreign matter around the piston ring is facilitated. The lower limit of the fuel injection amount QL1 is set so that the piston temperature will be 300[°C] or more when the fuel injection amount is reduced. can be made

When the process proceeds to step SB210, the control device 70 substitutes the center variable nozzle closing degree Vmid into the removal variable nozzle closing degree Vremv, which is the closing degree of the variable nozzles 31C and 32C (see FIG. 1) during the foreign matter removal operation. By doing so, the degree of closure of the variable nozzle during execution of the fuel sweep increase/decrease control (1) is fixed to the central variable nozzle degree of closure Vmid. For example, the central variable nozzle closing degree Vmid is set to a closing degree of 56[%]. In addition, the control device 70 substitutes the central injection timing Amid for the removal injection timing Aremv, which is the fuel injection timing during the foreign matter removal operation, so that the fuel injection timing during execution of the fuel sweep increase/decrease control (1) is centered. It is fixed at the injection timing Amid. For example, the central injection timing Amid is set to a value of injection timing -4 [°CA] (timing 4 [°CA] before top dead center). Then, control device 70 advances the process to step SB215.

At step SB215, control device 70 determines whether or not the timer is running. If the timer is running (Yes), the process proceeds to step SB230. The process proceeds to step SB220. The timer is used to measure the time required for the fuel injection amount to increase from the lower limit QL1 to the upper limit QH1 (or the time required to decrease from the upper limit QH1 to the lower limit QL1).

When the process proceeds to step SB220, the control device 70 initializes the timer (reset to 0) and activates the timer (starts measuring the elapsed time). Then, control device 70 advances the process to step SB225.

At step SB225, the control device 70 sets the increase sweep flag to ON, and substitutes QL1, which is the lower limit fuel injection amount (lower initial value), for the removal injection amount Qremv, which is the fuel injection amount during the foreign matter removal operation. Then, the process proceeds to step SB230. When the increase sweep flag is ON, the control device 70 determines that the increase sweep is being performed, and when the increase sweep flag is OFF, the control device 70 determines that the decrease sweep is being performed.

When the process proceeds to step SB230, the control device 70 determines whether or not the increase sweep flag is ON. If not ON (No), the process proceeds to step SB235B.

When the process proceeds to step SB235A, the control device 70 adds the minute injection amount ΔQ1 to the (current) removal injection amount Qremv to update the removal injection amount Qremv (increase the amount by a minute amount). The minute injection amount ΔQ1 is set to an appropriate value so as to increase gradually. Then, control device 70 advances the process to step SB240.

When the process proceeds to step SB235B, the control device 70 subtracts the minute injection amount ΔQ1 from the (current) removal injection amount Qremv to update the removal injection amount Qremv (reduce the amount by a minute amount). An appropriate value is set for the minute injection amount ΔQ1 so that the amount is gradually decreased. Then, control device 70 advances the process to step SB240.

When the process proceeds to step SB240, the control device 70 determines whether or not the timer is equal to or longer than the first injection sweep time. If it is less than the first injection sweep time (No), the process shown in FIG. 12 is terminated. After completing the process of FIG. 12, control device 70 advances the process to step SB185A shown in FIG. The first injection soup time is set to, for example, approximately 60 [sec], but is not limited to 60 [sec].

When the process proceeds to step SB245, the control device 70 initializes (resets to 0) the timer and restarts the timer (resumes measurement of elapsed time). Then, control device 70 advances the process to step SB250.

At step SB250, the control device 70 determines whether or not the increase sweep flag is ON. If the increase sweep flag is ON (Yes), the process proceeds to step SB255A. No) advances the process to step SB255B.

When the process proceeds to step SB255A, the control device 70 sets the increase sweep flag to OFF, substitutes QH1, which is the upper limit fuel injection amount (upper initial value), for the removal injection amount Qremv, and returns to FIG. Terminate the indicated process. After completing the process of FIG. 12, control device 70 advances the process to step SB185A shown in FIG.

When the process proceeds to step SB255B, the control device 70 sets the increase sweep flag to ON, substitutes QL1, which is the lower limit fuel injection amount (lower initial value), for the removal injection amount Qremv, and proceeds to step SB260. proceed to

In step SB260, control device 70 counts up first repetition counter C1 and advances the process to step SB265.

At step SB265, the control device 70 determines whether or not the first repetition counter C1 is equal to or greater than the first number of repetitions. If it is less than the number of repetitions (No), the process shown in FIG. 12 is terminated. After completing the process of FIG. 12, control device 70 advances the process to step SB185A shown in FIG. For example, the first repetition count is set to 10 [times], but is not limited to this value.

When the process has proceeded to step SB270, control device 70 stops the timer and ends the process shown in FIG. After completing the process of FIG. 12, control device 70 advances the process to step SB185A shown in FIG.

In the process SB200 (fuel sweep increase/decrease control (1)) described above, the fuel injection amount is controlled to gradually (and moderately) increase from time T10 to time T20 in FIG. Fuel sweep increase/decrease control (1) is executed, which repeats (and moderately) decreasing control. Then, in process SB200, fuel sweep increase control for gradually increasing the fuel injection amount for a predetermined period (first injection sweep time) to promote moistening of foreign matter (around the piston ring), and a predetermined period ( During the first injection sweep time), the fuel injection amount is gradually reduced to promote drying of the moistened foreign matter (around the piston ring), and a predetermined number of times (first repetition number) ) Repeatedly promotes the exfoliation of foreign matter around the piston ring.

● [SB300: Fuel sweep increase/decrease control (2) (Fig. 13)]
Next, details of the process SB300 (fuel sweep increase/decrease control (2)) of step SB135 in the flowchart of FIG. 11 will be described with reference to FIG. After executing process SB300 in step SB135 of FIG. 11, control device 70 advances the process to step SB310 shown in FIG. In the fuel sweep increase/decrease control (2), as shown from time T20 to time T30 in FIG. 23, the fuel injection amount is gradually increased relatively rapidly from QL2 to QH2, and then relatively rapidly gradually increased from QH2 to QL2. It is a control that reduces weight to In the fuel sweep increase/decrease control (2), the fuel injection amount is gradually increased for a predetermined period to promote moistening of foreign matter around the piston rings, and the fuel injection amount is gradually decreased for the predetermined period. This raises the combustion temperature and promotes drying of the moistened foreign matter. By repeating this for a predetermined number of times (the second number of repetitions), the exfoliation of foreign matter around the piston ring is facilitated. The lower limit of the fuel injection amount QL2 is set so that the piston temperature is 300° C. or more when the fuel injection amount is reduced, and the foreign matter around the piston ring is dried more reliably and appropriately. can be made

Processing SB300 shown in FIG. 13 differs from processing SB200 shown in FIG. 12 in that steps SB325, SB335A, SB335B, SB340, SB355A, SB355B, SB360, and SB365 indicated by bold frames are changed from those in FIG. However, since the other steps are the same as those in FIG. 12, description thereof will be omitted. Differences from the process SB200 shown in FIG. 12 will be mainly described below.

Steps SB310 to SB320 are the same as steps SB210 to SB220 shown in FIG. 12, so description thereof will be omitted.

When the process proceeds to step SB325, the control device 70 sets the increase sweep flag to ON, and sets the removal injection amount Qremv, which is the fuel injection amount during the foreign matter removal operation, to the lower limit fuel injection amount (lower initial value). is substituted for QL2, and the process proceeds to step SB330. When the increase sweep flag is ON, the control device 70 determines that the increase sweep is being performed, and when the increase sweep flag is OFF, the control device 70 determines that the decrease sweep is being performed.

When the process proceeds to step SB330, the control device 70 determines whether or not the increase sweep flag is ON. If not ON (No), the process proceeds to step SB335B.

When the process proceeds to step SB335A, the control device 70 adds the minute injection amount ΔQ2 to the (current) removal injection amount Qremv to update the removal injection amount Qremv (increase the amount by a minute amount). The minute injection amount ΔQ2 is set to an appropriate value so as to increase relatively rapidly. Then, control device 70 advances the process to step SB340.

When the process proceeds to step SB335B, the control device 70 subtracts the minute injection amount ΔQ2 from the (current) removal injection amount Qremv to update the removal injection amount Qremv (reduce the amount by a minute amount). The minute injection amount ΔQ2 is set to an appropriate value so as to decrease relatively rapidly. Then, control device 70 advances the process to step SB340.

When the process proceeds to step SB340, the control device 70 determines whether or not the timer is equal to or longer than the second injection sweep time. If it is less than the second injection sweep time (No), the process shown in FIG. 13 is terminated. After completing the process of FIG. 13, control device 70 advances the process to step SB185A shown in FIG. The second injection soup time is set to, for example, about 10 [sec], but is not limited to 10 [sec].

When the process proceeds to step SB345, the control device 70 initializes the timer (resets it to 0) and restarts the timer (resumes measurement of elapsed time). Then, control device 70 advances the process to step SB350.

At step SB350, the control device 70 determines whether or not the increase sweep flag is ON. If the increase sweep flag is ON (Yes), the process proceeds to step SB355A. No) advances the process to step SB355B.

When the process proceeds to step SB355A, the control device 70 sets the increase sweep flag to OFF, substitutes QH2, which is the upper limit fuel injection amount (upper initial value), for the removal injection amount Qremv, and returns to FIG. Terminate the indicated process. After completing the process of FIG. 13, control device 70 advances the process to step SB185A shown in FIG.

When the process proceeds to step SB355B, the control device 70 sets the increase sweep flag to ON, substitutes QL2, which is the lower limit fuel injection amount (lower initial value), for the removal injection amount Qremv, and proceeds to step SB360. proceed to

In step SB360, control device 70 counts up second repetition counter C2 and advances the process to step SB365.

At step SB365, the control device 70 determines whether or not the second repetition counter C2 is equal to or greater than the second number of repetitions. If it is less than the number of repetitions (No), the process shown in FIG. 13 is terminated. After completing the process of FIG. 13, control device 70 advances the process to step SB185A shown in FIG. For example, the second number of repetitions is set to 10 [times], but is not limited to this value.

If the process proceeds to step SB370, control device 70 stops the timer and ends the process shown in FIG. After completing the process of FIG. 13, control device 70 advances the process to step SB185A shown in FIG.

In the process SB300 (fuel sweep increase/decrease control (2)) described above, the fuel injection amount is controlled to gradually (and rapidly) increase from time T20 to time T30 in FIG. A fuel sweep increase/decrease control (2) is executed, which repeats the (and rapid) decrease control. In process SB300, fuel sweep increase control for gradually increasing the fuel injection amount for a predetermined period (second injection sweep time) to promote moistening of foreign matter (around the piston ring), and a predetermined period ( During the second injection sweep time), the fuel injection amount is gradually reduced to promote drying of the moistened foreign matter (around the piston ring), and a predetermined number of times (second repetition number) ) Repeatedly promotes the exfoliation of foreign matter around the piston ring.

● [SB400: boost pressure/exhaust pressure step increase/decrease control (Fig. 14)]
Next, details of the process SB400 (boost pressure/exhaust pressure step increase/decrease control) of step SB145 in the flowchart of FIG. 11 will be described with reference to FIG. After executing process SB400 in step SB145 of FIG. 11, control device 70 advances the process to step SB410 shown in FIG. In the boost pressure/exhaust pressure step increase/decrease control, as shown in time T30 to time T40 in FIG. The swinging state of the piston in the cylinder is promoted by stepwise changing to the decreasing variable nozzle closing degree Vdec. The piston swing state is a state in which the piston center axis 10FJ swings with respect to the cylinder center axis 10BJ shown in FIG. By setting the piston to the swinging state, it is promoted to shake off the foreign matter around the piston ring that has been peeled off by the fuel sweep increase/decrease control. The boost pressure/exhaust pressure step increase/decrease control is one of the piston swing controls for bringing the piston swing state.

When the process proceeds to step SB410, the control device 70 substitutes the central injection amount Qmid for the removal injection amount Qremv, which is the fuel injection amount during the foreign matter removal operation, thereby performing boost pressure/exhaust pressure step increase/decrease control. The rotational speed of the internal combustion engine during execution is substantially fixed at, for example, 3000 [rpm]. For example, the central injection amount Qmid is set to a value of 26 [mm ³ /stroke]. Further, the control device 70 substitutes the central injection timing Amid for the removal injection timing Aremv, which is the fuel injection timing during the foreign matter removal operation, so that the fuel injection timing during execution of the boost pressure/exhaust pressure step increase/decrease control is fixed at the central injection timing Amid. For example, the central injection timing Amid is set to a value of injection timing -4 [°CA] (timing 4 [°CA] before top dead center). Then, control device 70 advances the process to step SB415.

At step SB415, control device 70 determines whether or not the timer is running. If the timer is running (Yes), the process proceeds to step SB430. The process proceeds to step SB420. The timer measures the time to maintain the removal variable nozzle closing degree Vremv at the center variable nozzle closing degree Vmid, the time to maintain the increasing side variable nozzle closing degree Vinc, and the time to maintain the decreasing side variable nozzle closing degree Vdec. used for

When the process proceeds to step SB420, the control device 70 initializes the timer (reset to 0) and activates the timer (starts measuring the elapsed time). Then, control device 70 advances the process to step SB425.

In step SB425, the control device 70 sets the operation mode to "center Mid" and substitutes the central variable nozzle closing degree Vmid for the removal variable nozzle closing degree Vremv, which is the closing degree of the variable nozzle during the foreign matter removal operation, and step SB430. proceed to

When the process proceeds to step SB430, the control device 70 determines whether or not the timer has elapsed for the oscillation boost pressure time or more. If the oscillation supercharging pressure time or more has not passed (No), the process shown in FIG. 14 is terminated. 14, control device 70 advances the process to step SB185A shown in FIG. For example, the swing boost pressure time is set to 5 [sec], but it is not limited to this value.

When the process proceeds to step SB435, the control device 70 initializes (resets to 0) the timer and restarts the timer (resumes measurement of elapsed time). Then, control device 70 advances the process to step SB440.

At step SB440, the control device 70 determines whether or not the operation mode is the center Mid. If the operation mode is the center Mid (Yes), the process proceeds to step SB445. No) advances the process to step SB450.

When the process proceeds to step SB445, the control device 70 sets the operation mode to the increasing side Hi, substitutes the increasing side variable nozzle closing degree Vinc for the removal variable nozzle closing degree Vremv, and ends the processing shown in FIG. do. 14, control device 70 advances the process to step SB185A shown in FIG. For example, the increase-side variable nozzle closing degree Vinc is set to a closing degree of 65[%], but is not limited to this value.

When the process proceeds to step SB450, the control device 70 determines whether or not the operation mode=increase side Hi, and if the operation mode=increase side Hi (Yes), proceeds to step SB455, If the mode is not Hi on the increasing side (No), the process proceeds to step SB465.

When the process proceeds to step SB455, the control device 70 sets the operation mode to the decreasing side Lo, substitutes the decreasing variable nozzle closing degree Vdec for the removal variable nozzle closing degree Vremv, and ends the processing shown in FIG. do. 14, control device 70 advances the process to step SB185A shown in FIG. For example, the decreasing variable nozzle closing degree Vdec is set to a closing degree of 45[%], but is not limited to this value.

When the process proceeds to step SB465, the control device 70 sets the operation mode=center Mid, substitutes the removal variable nozzle closing degree Vremv with the central variable nozzle closing degree Vmid, and advances the processing to step SB470. For example, the central variable nozzle closing degree Vmid is set to a closing degree of 56[%], but is not limited to this value.

In step SB470, control device 70 counts up third repetition counter C3 and advances the process to step SB475.

At step SB475, the control device 70 determines whether or not the third repetition counter C3 is equal to or greater than the third number of repetitions. If it is less than the number of repetitions (No), the process shown in FIG. 14 is terminated. 14, control device 70 advances the process to step SB185A shown in FIG. For example, the third number of repetitions is set to 3 [times], but is not limited to this value.

When the process has proceeded to step SB480, control device 70 stops the timer and ends the process shown in FIG. 14, control device 70 advances the process to step SB185A shown in FIG.

In the processing SB400 (boost pressure/exhaust pressure step increase/decrease control) described above, the variable nozzle closing degree from time T30 to time T40 in FIG. The boost pressure/exhaust pressure step increase/decrease control is executed to repeat the control to change the degree Vinc --> the decreasing side variable nozzle closing degree Vdec in a stepwise manner. The boost pressure/exhaust pressure step increase/decrease control changes the variable nozzle closing degree stepwise to change the boost pressure of the internal combustion engine and the internal pressure of the exhaust manifold stepwise, thereby making the piston oscillate. do.

● [SB500: fuel injection timing step advance/retard control (Fig. 15)]
Next, details of the process SB500 (fuel injection timing step advance/retard control) of step SB155 in the flowchart of FIG. 11 will be described with reference to FIG. After executing process SB500 in step SB155 of FIG. 11, control device 70 advances the process to step SB510 shown in FIG. In the fuel injection timing step advance/retard control, as shown from time T40 to time T50 in FIG. --> By changing in a stepwise manner to the increase side injection timing Ainc, the swinging state of the piston in the cylinder is promoted. The piston swing state is a state in which the piston center axis 10FJ swings with respect to the cylinder center axis 10BJ shown in FIG. By setting the piston to the swinging state, it is promoted to shake off the foreign matter around the piston ring that has been peeled off by the fuel sweep increase/decrease control. The fuel injection timing step advance/retard control is one of the piston swing controls for achieving a piston swing state.

When the process proceeds to SB510, the control device 70 performs fuel injection timing step advance/retard control by substituting the central injection amount Qmid for the removal injection amount Qremv, which is the fuel injection amount during the foreign matter removal operation. The rotational speed of the internal combustion engine during execution is substantially fixed at, for example, 3000 [rpm]. For example, the central injection amount Qmid is set to a value of 26 [mm ³ /stroke]. Further, the control device 70 executes step advance/retard control of the fuel injection timing by substituting the center variable nozzle closing degree Vmid for the removal variable nozzle closing degree Vremv, which is the closing degree of the variable nozzle during the foreign matter removal operation. The closing degree of the middle variable nozzle is fixed to the central variable nozzle closing degree Vmid. For example, the central variable nozzle closing degree Vmid is set to a closing degree of 56[%]. Then, control device 70 advances the process to step SB515.

At step SB515, control device 70 determines whether or not the timer is running. If the timer is running (Yes), the process proceeds to step SB530. The process proceeds to step SB520. Note that the timer is used to measure the time during which the removal injection timing Aremv is maintained at the central injection timing Amid, the time during which it is maintained at the decreasing injection timing Adec, and the time during which it is maintained at the increasing injection timing Ainc.

When the process proceeds to step SB520, control device 70 initializes the timer (reset to 0) and activates the timer (starts measuring the elapsed time). Then, control device 70 advances the process to step SB525.

In step SB525, the control device 70 sets the operation mode to the middle Mid, substitutes the middle injection timing Amid for the removal injection timing Aremv, which is the start timing of fuel injection during the foreign matter removal operation, and proceeds to step SB530. .

When the process proceeds to step SB530, the control device 70 determines whether or not the timer has passed the oscillation injection timing time or more, and if the oscillation injection timing time or more has passed (Yes), the process proceeds to step SB535. , and if the oscillation injection timing time or more has not elapsed (No), the processing shown in FIG. 15 is terminated. 15, control device 70 advances the process to step SB185A shown in FIG. For example, the oscillation injection timing is set to 5 [sec], but is not limited to this value.

When proceeding to step SB535, the control device 70 initializes the timer (resets it to 0) and restarts the timer (resumes measurement of the elapsed time). Then, control device 70 advances the process to step SB540.

At step SB540, the control device 70 determines whether or not the operation mode is Central Mid. If the operation mode is Central Mid (Yes), the process proceeds to Step SB545. No) advances the process to step SB550.

When the process proceeds to step SB545, the control device 70 sets the operation mode to the decreasing side Lo, substitutes the decreasing side injection timing Adec for the elimination injection timing Aremv, and ends the processing shown in FIG. 15, control device 70 advances the process to step SB185A shown in FIG. For example, the decreasing injection timing Adec is set to -2 [° CA] (2 [° CA] before the top dead center), but is not limited to this value.

When the process proceeds to step SB550, the control device 70 determines whether or not the operation mode is on the decrease side Lo. If the mode is not Lo on the decrease side (No), the process proceeds to step SB565.

When the process proceeds to step SB555, the control device 70 sets the operation mode to the increasing side Hi, substitutes the increasing side injection timing Ainc for the removal injection timing Aremv, and ends the processing shown in FIG. 15, control device 70 advances the process to step SB185A shown in FIG. For example, the increasing injection timing Ainc is set to -6 [° CA] (6 [° CA] before the top dead center), but is not limited to this value.

When the process proceeds to step SB565, the control device 70 sets the operation mode=center Mid, substitutes the removed injection timing Aremv with the central injection timing Amid, and proceeds to step SB570. For example, the central injection timing Amid is set to -4 [°CA] (a timing 4 [°CA] before the top dead center), but is not limited to this value.

At step SB570, control device 70 counts up fourth repetition counter C4 and advances the process to step SB575.

At step SB575, the control device 70 determines whether or not the fourth repetition counter C4 is equal to or greater than the fourth repetition count. If it is less than the number of repetitions (No), the process shown in FIG. 15 is terminated. 15, control device 70 advances the process to step SB185A shown in FIG. For example, the fourth repetition count is set to 3 [times], but is not limited to this value.

When the process has proceeded to step SB580, control device 70 stops the timer and ends the process shown in FIG. 15, control device 70 advances the process to step SB185A shown in FIG.

In the process SB500 (fuel injection timing step advance/retard control) described above, the fuel injection start timing from time T40 to time T50 in FIG. Fuel injection timing step advance/retard control is executed to repeat stepwise retardation and advance from --> increasing side injection timing Ainc.

● [SB600: fuel step increase/decrease control (Fig. 16)]
Next, details of the process SB600 (fuel step increase/decrease control) of step SB165 in the flowchart of FIG. 11 will be described with reference to FIG. After executing process SB600 in step SB165 of FIG. 11, control device 70 advances the process to step SB610 shown in FIG. In the fuel step increase/decrease control, the fuel injection amount is changed stepwise from time T50 to time T60 in FIG. The change promotes the swinging state of the piston in the cylinder. The piston swing state is a state in which the piston center axis 10FJ swings with respect to the cylinder center axis 10BJ shown in FIG. By setting the piston to the swinging state, it is promoted to shake off the foreign matter around the piston ring that has been peeled off by the fuel sweep increase/decrease control. The fuel step increase/decrease control is one of the piston swing controls for setting the piston swing state.

When the process proceeds to step SB610, the control device 70 substitutes the central variable nozzle closing degree Vmid for the removal variable nozzle closing degree Vremv, which is the closing degree of the variable nozzle during the foreign matter removal operation, to perform fuel step increase/decrease control. is fixed to the central variable nozzle closing degree Vmid. For example, the central variable nozzle closing degree Vmid is set to a closing degree of 56[%]. Further, the control device 70 assigns the central injection timing Amid to the removal injection timing Aremv, which is the fuel injection timing during the foreign matter removal operation, so that the fuel injection timing during execution of the fuel step increase/decrease control is set to the central injection timing Amid. fixed to For example, the central injection timing Amid is set to a value of injection timing -4 [°CA] (timing 4 [°CA] before top dead center). Then, control device 70 advances the process to step SB615.

At step SB615, control device 70 determines whether or not the timer is running. If the timer is running (Yes), the process proceeds to step SB630. The process proceeds to step SB620. The timer is used to measure the time during which the removal injection amount Qremv is maintained at the central injection amount Qmid, the time during which the increased injection amount Qinc is maintained, and the time during which the decreased injection amount Qdec is maintained.

When the process proceeds to step SB620, control device 70 initializes the timer (reset to 0) and activates the timer (starts measuring the elapsed time). Then, control device 70 advances the process to step SB625.

At step SB625, the control device 70 sets the operation mode=center-Mid, substitutes the center injection amount Qmid for the removal injection amount Qremv, which is the fuel injection amount during the foreign matter removal operation, and proceeds to step SB630.

When the process proceeds to step SB630, the control device 70 determines whether or not the timer has passed the oscillation injection time or more, and if the oscillation injection time or more has elapsed (Yes), the process proceeds to step SB635. If the oscillation injection time or more has not elapsed (No), the processing shown in FIG. 16 is terminated. 16, control device 70 advances the process to step SB185A shown in FIG. For example, the oscillation injection time is set to 5 [sec], but it is not limited to this value.

When proceeding to step SB635, the control device 70 initializes the timer (resets it to 0) and restarts the timer (resumes measurement of the elapsed time). Then, control device 70 advances the process to step SB640.

At step SB640, the control device 70 determines whether or not the operation mode is Central Mid. If the operation mode is Central Mid (Yes), the process proceeds to Step SB645. No) advances the process to step SB650.

When the process proceeds to step SB645, the control device 70 sets the operation mode=increase side Hi, substitutes the increase side injection amount Qinc for the removed injection amount Qremv, and ends the process shown in FIG. 16, control device 70 advances the process to step SB185A shown in FIG. For example, the increased injection amount Qinc is set to 28 [mm ³ /stroke], but is not limited to this value.

When the process proceeds to step SB650, the control device 70 determines whether or not the operation mode=increase side Hi, and if the operation mode=increase side Hi (Yes), proceeds to step SB655, and If the mode is not Hi on the increasing side (No), the process proceeds to step SB665.

When the process proceeds to step SB655, the control device 70 sets the operation mode to the decrease side Lo, substitutes the decrease side injection amount Qdec for the removal injection amount Qremv, and ends the process shown in FIG. 16, control device 70 advances the process to step SB185A shown in FIG. For example, the decreasing side injection amount Qdec is set to 24 [mm ³ /stroke], but is not limited to this value.

When the process proceeds to step SB665, the control device 70 sets the operation mode=center Mid, substitutes the removed injection amount Qremv with the central injection amount Qmid, and proceeds to step SB670. For example, the central injection amount Qmid is set to 26 [mm ³ /stroke], but is not limited to this value.

In step SB670, control device 70 counts up fifth repetition counter C5 and advances the process to step SB675.

At step SB675, the control device 70 determines whether or not the fifth repetition counter C5 is equal to or greater than the fifth number of repetitions. If it is less than the number of repetitions (No), the process shown in FIG. 16 is terminated. 16, control device 70 advances the process to step SB185A shown in FIG. For example, the fifth repetition count is set to 3 [times], but is not limited to this value.

If the process has proceeded to step SB680, control device 70 stops the timer and ends the process shown in FIG. 16, control device 70 advances the process to step SB185A shown in FIG.

In the processing SB600 (fuel step increase/decrease control) described above, the fuel injection amount from time T50 to time T60 in FIG. A fuel step increase/decrease control is executed to repeat the control to change stepwise to .

● [SC100: Post-removal confirmation process (Fig. 17)]
Next, details of the process SC100 (post-removal confirmation process) of step S070 in the flowchart of FIG. 6 will be described with reference to FIG. After executing the process SB100 (foreign matter removal process) in step S050 of FIG. 6, the control device 70 determines whether or not the foreign matter is actually removed in the executed process SB100 (foreign matter removal process). It is confirmed in SC100 (post-removal confirmation process). After executing process SC100 in step S070 of FIG. 6, control device 70 advances the process to step SC110 shown in FIG. Note that the post-removal confirmed flag, the post-removal confirmation flag, and the removal complete flag are set to "OFF" as initial values.

During execution of the process SC100 (post-removal confirmation process) shown in FIG. 17, the post-removal confirmation flag is set to ON. When the post-removal confirmation flag is set to ON, the final injection amount, which is the fuel injection amount finally output, is switched to the removal injection amount Qremv as shown in FIG. Details of the processing in FIG. 20 will be described later.

When the process proceeds to step SC110, the control device 70 checks whether the foreign matter has been removed by setting the internal combustion engine to an idling state (for example, the number of revolutions = 1000 [rpm]). The post-confirmation flag is set to ON, the idling injection amount Qid is substituted for the removed injection amount Qremv, and the process proceeds to step SC115. The idling injection amount Qid is set to an injection amount for bringing the internal combustion engine into an idling state.

In step SC115, the control device 70 determines whether or not the operating state of the internal combustion engine satisfies (establishes) a third detection condition. The process proceeds to SC120, and if the third detection condition is not satisfied (established), the process proceeds to step SC125B. The third detection condition is, for example, that "the operating state of the internal combustion engine is in the idling state" and "the fluctuation of the engine speed is within the allowable engine speed fluctuation range, or the load fluctuation of the internal combustion engine is within the allowable load fluctuation." It is a condition that includes "within range".

When the process proceeds to step SC120, the control device 70 determines whether or not the timer is running, and if the timer is running (Yes), the process proceeds to step SC130 and the timer is not running. In the case (No), the process proceeds to step SC125A. The timer in this case measures the elapsed time after the third detection condition in step SC115 is satisfied (established).

When the process proceeds to step SC125A, the control device 70 initializes (resets to 0) the timer and activates the timer (starts measuring the elapsed time). The control device 70 also initializes the value of the variable i to "1". When the third detection condition is satisfied, the control device 70 executes the process SC100 at predetermined time intervals for a third predetermined period of time in subsequent processes to measure and store the crankcase internal pressure [i]. . In the subsequent processing, for example, when the crankcase internal pressure is measured 100 times during the third predetermined time period, the control device 70 stores the crankcase internal pressure [1] to the crankcase internal pressure [100].

When the process proceeds to step SC125B, the control device 70 stops the timer (stops measuring the elapsed time) and ends the process shown in FIG. After completing the process of FIG. 17, the control device 70 advances the process to step S075 shown in FIG.

When the process proceeds to step SC130, the control device 70 acquires the crankcase internal pressure based on the detection signal from the pressure detection means 22P (see FIGS. 1 and 2), and uses the value of the variable i to The case internal pressure [i] is stored. The control device 70 also counts up the value of the variable i in preparation for the crankcase internal pressure to be acquired and stored next. Then, control device 70 advances the process to step SC135.

The control device 70 (CPU 71) executing the processing of step SC130 sets the operating state of the internal combustion engine to a predetermined operating state (idling state) after the foreign matter removing operation mode by the foreign matter removing operation execution unit 71I (see FIG. 1) is completed. ) and acquires the crankcase internal pressure, which is the pressure in the crankcase of the internal combustion engine, for a third predetermined time period (see FIG. 1). It should be noted that when the internal combustion engine is brought into the predetermined operating state, it may be in an operating state other than the idling state.

In step SC135, the control device 70 determines whether or not the elapsed time measured by the timer is equal to or longer than a third predetermined time. If it is less than 3 predetermined times (No), the process shown in FIG. 17 is terminated. After completing the process of FIG. 17, the control device 70 advances the process to step S075 shown in FIG. Note that the value of the third predetermined time is appropriately set, and is, for example, about several tens [sec] to several [min].

When the process proceeds to step SC140, the control device 70 stops the operation of the timer (stops measuring the elapsed time) and proceeds to step SC145.

In step SC145, control device 70 executes process SC200 (abnormality re-detection process) and advances the process to step SC150. The details of the process SC200 (abnormality re-detection process) will be described later.

In step SC150, control device 70 sets the post-removal confirmation flag to ON, and terminates the processing shown in FIG. After completing the process of FIG. 17, the control device 70 advances the process to step S075 shown in FIG. Since the post-removal confirmation flag is set to ON, the control device 70 can recognize that confirmation of the result of executing the foreign matter removal operation mode has been completed in step SC100.

● [SC200: Abnormality re-detection process (Fig. 18)]
Next, details of the process SC200 (abnormality re-detection process) of step SC145 in the flowchart of FIG. 17 will be described with reference to FIG. After executing process SC200 in step SC145 of FIG. 17, control device 70 advances the process to step SC210 shown in FIG.

When the process proceeds to step SC210, the control device 70 stores the plurality of stored crankcase internal pressures [1] to [p] as data having a pressure difference within ±ΔP between the front and rear and k or more continuous data. The data are classified into groups Ad, Bd, . . . , and the process proceeds to step SC215. Note that the values of ΔP and k are appropriately set. Note that this process is the same as the process of step SA210 shown in FIG. 8, so the description is omitted.

In step SC215, control device 70 calculates the average pressure of each data group and advances the process to step SC220. Note that this process is the same as the process of step SA215 shown in FIG. 8, so description thereof will be omitted.

In step SC220, the control device 70 determines that at least one of the differences between the average pressures of adjacent data groups (corresponding to a pressure step that is a step-like fluctuation amount) is equal to or greater than the third abnormal step pressure set as the threshold for abnormality determination. If at least one is equal to or higher than the third abnormal step pressure (Yes), the process proceeds to Step SC225A; otherwise (No), the process proceeds to Step SC225B. Note that this process is the same as the process of step SA220 shown in FIG. 8, so description thereof will be omitted. An appropriate value for the third abnormal bump pressure is selected through experiments, simulations, or the like using an actual vehicle.

When the process proceeds to step SC225A, the control device 70 sets the removal completion flag to ON, and ends the process shown in FIG. After completing the process of FIG. 18, control device 70 advances the process to step SC150 shown in FIG.

When the process proceeds to step SC225B, the control device 70 sets the removal completion flag to OFF, and ends the process shown in FIG. After completing the process of FIG. 18, control device 70 advances the process to step SC150 shown in FIG.

The control device 70 (CPU 71) executing the process SC200 performs the process of the abnormality detection section 71D (see FIG. 1) in correspondence with the acquisition of the crankcase internal pressure by the third crankcase internal pressure acquisition section 71J (see FIG. 1). It corresponds to the foreign matter removal confirmation section 71K (see FIG. 1) that executes and detects whether foreign matter is deposited around the piston ring of the internal combustion engine.

● [Existing turbo mode switching process (Fig. 19)]
Next, with reference to FIG. 19, changes in the existing turbo mode switching process (control of the intake bypass valve, the intake switching valve, and the exhaust switching valve) will be described. When executing the foreign object removal operation mode described above, the existing turbo mode switching process (1 turbo mode<->2 turbo mode switching process) is stopped and the 2 turbo mode is fixed. When executing the turbo mode switching process, the control device 70 advances the process to step STM010. In the case of the 1-turbo mode, the control device 70 controls the intake bypass valve 61 = closed, the intake switching valve 62 = closed, and the exhaust switching valve 63 = closed shown in FIG. Closed, intake switching valve 62 = open, exhaust switching valve 63 = open.

When the process proceeds to step STM010, the control device 70 determines whether or not the foreign matter removal flag=ON, and if the foreign matter removal flag=ON (Yes), advances the process to step STM015B. If the foreign matter removal flag is not ON (No), the process proceeds to step STM015A.

When proceeding to step STM015A, the control device 70 substitutes the switching mode calculated in the existing process for the turbo switching mode, and advances the process to step STM020.

When proceeding to step STM015B, the control device 70 substitutes information for fixing the 2-turbo mode into the turbo switching mode, and advances the process to step STM020.

When the process proceeds to step STM020, the control device 70 controls the intake bypass valve, the intake switching valve, and the exhaust switching valve based on the turbo switching mode, and ends the process.

● [Existing injection amount calculation process (Fig. 20)]
Next, with reference to FIG. 20, changes in the existing injection amount calculation process will be described. When executing the above-described foreign matter removal operation mode and when executing the post-removal confirmation process, the fuel injection amount set to the removal injection amount Qremv is injected instead of the injection amount Qstd obtained by the existing process. . When executing the injection amount calculation process, control device 70 advances the process to step SQ010.

When the process proceeds to step SQ010, the control device 70 calculates the injection amount Qstd by the existing process, and proceeds to step SQ015.

In step SQ015, the controller 70 determines whether or not the foreign matter removal flag is ON. If the foreign matter removal flag is ON (Yes), the process proceeds to step SQ025B, where If the flag is not ON (No), the process proceeds to step SQ020.

When the process proceeds to step SQ020, the control device 70 determines whether or not the post-removal confirmation flag=ON, and if the post-removal confirmation flag=ON (Yes), the process proceeds to step SQ025B. If the post-removal confirmation flag is not ON (No), the process proceeds to step SQ025A.

When the process proceeds to step SQ025A, the control device 70 substitutes the injection amount Qstd obtained in the existing process for the final injection amount Q used for injection, and ends the process.

When the process proceeds to step SQ025B, the control device 70 substitutes the removed injection amount Qremv for the final injection amount Q used for injection, and ends the process.

● [Existing variable nozzle closing degree calculation process (Fig. 21)]
Next, with reference to FIG. 21, changes in the existing variable nozzle closing degree calculation process will be described. When executing the foreign matter removal operation mode described above, the variable nozzles are controlled by the closing degree set to the removal variable nozzle closing degree Vremv instead of the variable nozzle closing degree Vstd obtained by the existing process. When executing the variable nozzle closing degree calculation process, the control device 70 advances the process to step SV010.

When the process proceeds to step SV010, the control device 70 calculates the variable nozzle closing degree Vstd by the existing process, and proceeds to step SV015.

In step SV015, the controller 70 determines whether or not the foreign matter removal flag is ON. If the foreign matter removal flag is ON (Yes), the process proceeds to step SV020B, where If the flag is not ON (No), the process proceeds to step SV020A.

When the process proceeds to step SV020A, the control device 70 substitutes the variable nozzle closing degree Vstd obtained in the existing process for the final variable nozzle closing degree V used for the final output of the variable nozzle closing degree and executes the process. finish.

When the process proceeds to step SV020B, the control device 70 substitutes the removal variable nozzle closing degree Vremv into the final variable nozzle closing degree V used for the final output of the variable nozzle closing degree, and ends the processing.

● [Existing injection timing calculation process (Fig. 22)]
Next, with reference to FIG. 22, changes in the existing injection timing calculation process will be described. When executing the foreign matter removal operation mode described above, fuel injection is started at the injection timing set as the removal injection timing Aremv instead of the injection timing Astd obtained by the existing process. When executing the injection timing calculation process, control device 70 advances the process to step SZ010.

When the process proceeds to step SZ010, the control device 70 calculates the injection timing Astd by the existing process, and proceeds to step SZ015.

In step SZ015, the controller 70 determines whether or not the foreign matter removal flag is ON. If the foreign matter removal flag is ON (Yes), the process proceeds to step SZ020B, where If the flag is not ON (No), the process proceeds to step SZ020A.

When the process proceeds to step SZ020A, the control device 70 substitutes the injection timing Astd obtained in the existing process for the final injection timing A used for the final output of the fuel injection start timing, and ends the process.

When the process proceeds to step SZ020B, the control device 70 substitutes the removal injection timing Aremv for the final injection timing A used for the final output of the fuel injection start timing, and ends the processing.

● [Processing procedure of the overall process of the control device 70 in the second embodiment (Fig. 24)]
Next, the processing procedure of the second embodiment of the control device 70 will be described with reference to FIGS. 24 to 28. FIG. When detecting a foreign object, in the first embodiment, the presence or absence of a foreign object is detected based on the presence or absence of an abnormal step pressure in the crankcase internal pressure. The difference is that the presence or absence of a foreign object is detected depending on whether the deviation from the reference internal pressure obtained is equal to or greater than a threshold value. Note that the foreign matter removal operation mode is the same as in the first embodiment, so the description is omitted. First, with reference to FIG. 24, the overall processing of the second embodiment will be mainly described with respect to differences from the overall processing of the first embodiment (FIG. 6).

As in the first embodiment shown in FIG. 6, the overall processing of the second embodiment shown in FIG. After being activated, control device 70 (CPU 71) advances the process to step S010. Note that when the control device 70 is activated, the foreign matter detection end flag, the (final) foreign matter present flag, the foreign matter removal completed flag, the foreign matter removal in progress flag, the post-removal confirmation flag, the post-removal confirmation flag, the removal As in the first embodiment, various flags such as the completion flag are set to OFF as initial values.

In the overall processing of the second embodiment shown in FIG. 24, in contrast to the first embodiment shown in FIG. has been changed to Further, in the overall processing of the second embodiment shown in FIG. 24, the processing of step S070 is changed from processing SC100 (post-removal confirmation processing) to processing SE100 (removal post-confirmation process). Other steps are the same as those of the second embodiment shown in FIG. 24 and the first embodiment shown in FIG. Details of the process SD100 (foreign matter detection process) and the process SE100 (post-removal confirmation process) will be described below.

● [SD100: Foreign matter detection processing (Figs. 25 to 27)]
Next, details of the process SD100 (foreign object detection process) of step S020 in the flowchart of FIG. 24 will be described with reference to FIG. After executing process SD100 in step S020 of FIG. 24, control device 70 advances the process to step SD110 shown in FIG.

When the process proceeds to step SD110, the control device 70 determines whether or not the foreign object detection (provisional) end flag=ON.If the foreign object detection (provisional) end flag=ON (Yes), step SD155 If the foreign matter detection (temporary) end flag is not ON (No), the process proceeds to step SD115. In process SD100, the controller 70 performs foreign object detection (abnormality detection) twice just in case, and turns on the foreign object detection (provisional) end flag when the first foreign object detection (abnormality detection) is completed. The point is the same as in the first embodiment.

When the process proceeds to step SD115, the control device 70 determines whether or not the operating state of the internal combustion engine satisfies the first detection condition, and if the first detection condition is satisfied (Yes), step The process proceeds to SD120, and if the first detection condition is not satisfied (No), the process proceeds to step SD125B. The first detection condition is the same as in the first embodiment, and includes, for example, "the state after the internal combustion engine warms up" and "the load of the internal combustion engine (the load obtained based on the rotation speed and the fuel injection amount ) is within the allowable load fluctuation range, or the fluctuation amount of the rotational speed of the internal combustion engine is within the allowable rotational speed fluctuation range.

Based on the detected operating state of the internal combustion engine, the control device 70 (CPU 71) executing the process of step SD115 determines whether the amount of fluctuation in the load of the internal combustion engine is within the allowable load fluctuation range or the amount of fluctuation in the rotational speed of the internal combustion engine. is within the permissible rotational speed variation range and the internal combustion engine has already warmed up (first detection condition). ).

When the process proceeds to step SD120, the control device 70 determines whether or not the timer is running. If the timer is running (Yes), the process proceeds to step SD130 and the timer is not running. If not (No), the process proceeds to step SD125A. Note that the timer in this case measures the elapsed time after the first detection condition in step SD115 is satisfied.

When the process proceeds to step SD125A, control device 70 initializes (resets to 0) the timer, starts the timer (starts measuring the elapsed time), is set to OFF, and the process proceeds to step SD130. When the first detection condition is satisfied, the control device 70 executes the process SD100 at predetermined time intervals for a first predetermined period of time in subsequent processes to measure the internal pressure of the crankcase. The presence or absence of abnormality is determined based on the deviation between the measured crankcase internal pressure and the reference internal pressure.

When the process proceeds to step SD125B, the control device 70 stops the timer (stops measuring the elapsed time) and ends the process shown in FIG. After completing the process of FIG. 25, the control device 70 advances the process to step S025 shown in FIG.

When the process proceeds to step SD130, the control device 70 acquires the crankcase internal pressure based on the detection signal from the pressure detection means 22P (see FIGS. 1 and 2). Further, the reference crankcase internal pressure characteristic shown in FIG. 27 is stored in the storage means 73 of the control device 70 . The reference crankcase internal pressure characteristic shown in FIG. 27 is the reference pressure in the crankcase when no foreign matter is deposited around the piston rings, depending on the operating state (load or rotation speed) of the internal combustion engine. A certain reference internal pressure is set, and is set based on actual vehicles, simulations, and the like. The control device 70 determines a reference internal pressure ( equivalent to the reference pressure). Then, the control device 70 obtains a first pressure deviation (=acquired crankcase internal pressure - reference internal pressure), which is the difference between the acquired crankcase internal pressure and the reference internal pressure, and advances the process to step SD135. It should be noted that the reference crankcase internal pressure characteristic may be set to a reference internal pressure corresponding to the operating state of the internal combustion engine, and the operating state is not limited to the load or the number of revolutions. shape).

The control device 70 (CPU 71) executing the process of step SD130 detects the pressure in the crankcase of the internal combustion engine, which is one of the operating conditions of the internal combustion engine (when the detection condition (first detection condition) is satisfied). corresponds to the first crankcase internal pressure acquisition unit 71C (see FIG. 1) that acquires the crankcase internal pressure for a first predetermined period of time.

In step SD135, the control device 70 determines whether or not the first pressure deviation is equal to or greater than the first abnormality determination pressure set as the threshold value for abnormality determination. If there is (Yes), the process proceeds to step SD140, and if the first pressure deviation is less than the first abnormality determination pressure (No), the process proceeds to step SD145.

For example, the first abnormality determination pressure is the reference internal pressure (that is, step Set to less than half of the pressure difference between the reference internal pressure obtained by SD130, the reference internal pressure obtained based on the internal combustion engine idling state (load or rotation speed), and the reference crankcase internal pressure characteristics. is the value For example, in FIG. 27, the first abnormality determination pressure is a reference internal pressure Psid obtained from the idling speed Neid (or load) of the internal combustion engine, and a reference internal pressure Ps1 obtained from the current speed Ne1 (or load) of the internal combustion engine. , is set to a value less than half of the pressure difference ΔPs between . Note that when the current operating state (load or speed) of the internal combustion engine is idling or near idling, the first abnormality determination pressure is instead of the above "value less than half the pressure difference ΔPs" , the first abnormality determination pressure of a value set separately in advance is used. Alternatively, the first detection condition of step SD115 may include the condition "not idling". Although the reference internal pressure Psid is constant in the idling state, the reference internal pressure Ps1 fluctuates according to the current rotational speed (or load) of the internal combustion engine, so the first abnormality determination pressure also fluctuates.

When the process proceeds to step SD140, the control device 70 sets the (temporary) abnormality flag to ON and proceeds to step SD145. For example, in the example shown in FIG. 26, the (temporary) abnormality flag is set to ON between time Ta and time Tb. Note that the example of FIG. 25 shows an example in which the (provisional) abnormality flag is set to ON when the first pressure deviation exceeds the first abnormality determination pressure even once. The number of times it is determined that the pressure is equal to or higher than the first abnormality determination pressure may be obtained, and if the number of times is equal to or greater than a predetermined number, the (provisional) abnormality flag may be set to ON.

When the process proceeds to step SD145, the control device 70 determines whether or not the elapsed time measured by the timer is equal to or longer than the first predetermined time. The process proceeds, and if it is less than the first predetermined time (No), the process shown in FIG. 25 ends. After completing the process of FIG. 25, the control device 70 advances the process to step S025 shown in FIG. Note that the value of the first predetermined time is appropriately set, and is, for example, about several tens [sec] to several [min] as in the first embodiment.

When the process proceeds to step SD147, the control device 70 stops the operation of the timer (stops measuring the elapsed time) and proceeds to step SD150.

In step SD150, control device 70 sets a foreign object detection (provisional) end flag to ON, and proceeds to step SD155. Since the foreign object detection (provisional) end flag is set to ON, the control device 70 recognizes in steps SD115 to SD147 that the first foreign object detection (abnormality detection) performed twice has ended. can be done.

The control device 70 (CPU 71) executing the processes of steps SD115 to SD150 of the process SD100 obtains the crankcase internal pressure based on the acquired crankcase internal pressure, the operating state (load or rotation speed) of the internal combustion engine, and the reference crankcase internal pressure characteristics. The pressure deviation (first pressure deviation) that is the deviation between the reference internal pressure and the pressure deviation (first pressure deviation) that is equal to or higher than the abnormality determination pressure (first abnormality determination pressure) set as the threshold value for abnormality determination is determined. It corresponds to the abnormality detection section 71D (see FIG. 1) that detects the presence or absence of accumulation of foreign matter around the piston ring of the internal combustion engine based on the presence or absence.

When the process proceeds to step SD155, the control device 70 determines whether or not the (temporary) abnormality flag is ON, and if the (temporary) abnormality flag is ON (Yes), the process proceeds to step SD160. If the (temporary) abnormality flag is not ON (No), the process proceeds to step SD195. The (temporary) abnormality flag is a flag that is turned ON when an abnormality is detected in steps SD115 to SD147, which are the first foreign matter detection (abnormality detection) processes.

When the process proceeds to step SD160, the control device 70 determines whether or not the operating state of the internal combustion engine satisfies the second detection condition, and if the second detection condition is satisfied (Yes), step The process proceeds to SD165, and if the second detection condition is not satisfied (No), the process proceeds to step SD170B. As in the first embodiment, the second detection condition is, for example, a condition including "the operating state of the internal combustion engine is the idling state".

The control device 70 (CPU 71) executing the process of step SD160 determines that foreign matter has accumulated around the piston ring of the internal combustion engine in the abnormality detection section 71D (see FIG. 1, corresponding to steps SD115 to SD150). is detected ((temporary) abnormality flag = ON), whether the re-detection condition (second detection condition) including that the operating state of the internal combustion engine is in the idling state (predetermined operating state) is satisfied It corresponds to the redetection condition determination unit 71E (see FIG. 1) that determines The "predetermined operating state" is not limited to the idling state, and can be set to various operating states.

When the process proceeds to step SD165, the control device 70 determines whether or not the timer is running, and if the timer is running (Yes), the process proceeds to step SD175 and the timer is not running. If not (No), the process proceeds to step SD170A. Note that the timer in this case measures the elapsed time after the second detection condition in step SD160 is satisfied.

When the process proceeds to step SD170A, control device 70 initializes the timer (resets it to 0), activates the timer (starts measuring the elapsed time), is set to OFF, and the process proceeds to step SD175. When the second detection condition is satisfied, the control device 70 executes the process SD100 at predetermined time intervals for a second predetermined period of time in subsequent processes to measure the internal pressure of the crankcase. The presence or absence of abnormality is determined based on the deviation between the measured crankcase internal pressure and the reference internal pressure.

When the process has proceeded to step SD170B, control device 70 stops the timer (stops measuring the elapsed time) and ends the process shown in FIG. After completing the process of FIG. 25, the control device 70 advances the process to step S025 shown in FIG.

When the process proceeds to step SD175, the control device 70 acquires the crankcase internal pressure based on the detection signal from the pressure detection means 22P (see FIGS. 1 and 2). In addition, the control device 70 controls the current operating state (load or the number of revolutions) to obtain the reference internal pressure. Then, the control device 70 obtains a second pressure deviation (=acquired crankcase internal pressure−reference internal pressure), which is the difference between the acquired crankcase internal pressure and the reference internal pressure, and advances the process to step SD185.

The control device 70 (CPU 71) executing the process of step SD175 detects that foreign matter has accumulated around the piston ring of the internal combustion engine in the abnormality detection section 71D (see FIG. 1) (and A second crank for obtaining, for a second predetermined time, a crankcase internal pressure, which is the pressure in the crankcase of the internal combustion engine, which is one of the operating states of the internal combustion engine (when a detection condition (second detection condition) is satisfied). It corresponds to the case internal pressure acquisition unit 71F (see FIG. 1).

In step SD180, the control device 70 determines whether or not the second pressure deviation is equal to or greater than the second abnormality determination pressure set as the threshold value for abnormality determination. If there is (Yes), the process proceeds to step SD185, and if the second pressure deviation is less than the second abnormality determination pressure (No), the process proceeds to step SD190.

It should be noted that the second abnormality determination pressure is set to an appropriate value that enables abnormality to be determined in the idling state by an actual vehicle, simulation, or the like.

When the process proceeds to step SD185, control device 70 sets the (final) abnormality flag to ON and proceeds to step SD190. Note that the example of FIG. 25 shows an example in which the (final) abnormality flag is set to ON when the second pressure deviation exceeds the second abnormality determination pressure even once. The number of times it is determined that the pressure is equal to or higher than the second abnormality determination pressure may be obtained, and if the number of times is equal to or greater than a predetermined number, the (final) abnormality flag may be set to ON.

Further, the control device 70 (CPU 71) executing the processes of steps SD155 to SD195 causes the abnormality re-detection unit 71G (see FIG. 1) to re-detect , when it is detected that there is accumulation of foreign matter around the piston ring of the internal combustion engine, it is determined that there is accumulation of foreign matter around the piston ring of the internal combustion engine (the (final) abnormality flag is set to ON) ), and corresponds to the abnormality determination determination unit 71H (see FIG. 1).

When the process proceeds to step SD190, the control device 70 determines whether or not the elapsed time measured by the timer is equal to or longer than the second predetermined time. The process proceeds, and if it is less than the second predetermined time (No), the process shown in FIG. 25 ends. After completing the process of FIG. 25, the control device 70 advances the process to step S025 shown in FIG. Note that the value of the second predetermined time is appropriately set, and is, for example, about several tens [sec] to several [min] as in the first embodiment.

When the process proceeds to step SD192, the control device 70 stops the operation of the timer (stops measuring the elapsed time) and proceeds to step SD195.

When the process proceeds to step SD195, the control device 70 sets the foreign object detection end flag to ON and ends the process shown in FIG. After completing the process of FIG. 25, the control device 70 advances the process to step S025 shown in FIG. The control device 70 can recognize that the process SD100 (foreign object detection process) has ended by setting the foreign object detection end flag to ON.

Note that the control device 70 (CPU 71) executing steps SD160 to SD192 controls the acquisition of the crankcase internal pressure by the second crankcase internal pressure acquisition unit 71F (see FIG. 1). ) (performs the same abnormality determination as the abnormality detection unit 71D), and corresponds to the abnormality redetection unit 71G (see FIG. 1). The control device 70 determines an abnormality ((temporary) abnormality flag=ON) in the abnormality detection section 71D that is the first abnormality detection (foreign object detection), and furthermore, the second abnormality redetection (foreign object redetection). If an abnormality is determined in , the abnormality is confirmed (the (final) abnormality flag is set to ON).

● [SE100: Post-removal confirmation process (Fig. 28)]
Next, details of the process SE100 (post-removal confirmation process) of step S070 in the flowchart of FIG. 24 will be described with reference to FIG. After executing the process SB100 (foreign matter removal process) in step S050 of FIG. 24, the control device 70 determines whether or not the foreign matter is actually removed in the executed process SB100 (foreign matter removal process). Confirmation is performed in SE100 (confirmation processing after removal). After executing process SE100 in step S070 of FIG. 24, control device 70 advances the process to step SE110 shown in FIG. Note that the post-removal confirmed flag, the post-removal confirmation flag, and the removal complete flag are set to "OFF" as initial values.

During execution of the process SE100 (post-removal confirmation process) shown in FIG. 28, the post-removal confirmation flag is set to ON. When the post-removal confirmation flag is set to ON, as in the first embodiment, the final injection amount, which is the fuel injection amount that is finally output, is switched to the removal injection amount Qremv as shown in FIG. .

When the process proceeds to step SE110, the control device 70 checks whether the foreign matter has been removed by setting the internal combustion engine to an idling state (for example, the number of revolutions = 1000 [rpm]). The post-confirmation flag is set to ON, the idling injection amount Qid is substituted for the removed injection amount Qremv, and the process proceeds to step SE115. The idling injection amount Qid is set to an injection amount for bringing the internal combustion engine into an idling state.

At step SE115, the control device 70 determines whether or not the operating state of the internal combustion engine satisfies the third detection condition, and if the third detection condition is satisfied (Yes), the process proceeds to step SE120, If the third detection condition is not satisfied, the process proceeds to step SE125B. The third detection condition is, for example, that "the operating state of the internal combustion engine is in the idling state" and "the fluctuation of the engine speed is within the allowable engine speed fluctuation range, or the load fluctuation of the internal combustion engine is within the allowable load fluctuation." It is a condition that includes "within range".

When the process proceeds to step SE120, the control device 70 determines whether or not the timer is running. If the timer is running (Yes), the process proceeds to step SE130 and the timer is not running. If not (No), the process proceeds to step SE125A. Note that the timer in this case measures the elapsed time after the third detection condition in step SE115 is satisfied.

When the process proceeds to step SE125A, the control device 70 initializes (resets to 0) the timer, activates the timer (starts measuring the elapsed time), and sets the post-removal foreign matter flag just in case. It is set to OFF, and the process proceeds to step SE130. When the third detection condition is satisfied, the control device 70 executes the process SE100 at predetermined time intervals for a third predetermined period of time in subsequent processes to measure the internal pressure of the crankcase. The presence or absence of abnormality is determined based on the deviation between the measured crankcase internal pressure and the reference internal pressure.

When the process proceeds to step SE125B, control device 70 stops the timer (stops measuring the elapsed time) and ends the process shown in FIG. After completing the process of FIG. 28, the control device 70 advances the process to step S075 shown in FIG.

When the process proceeds to step SE130, the control device 70 acquires the crankcase internal pressure based on the detection signal from the pressure detection means 22P (see FIGS. 1 and 2). In addition, the control device 70 controls the current operating state (load or the number of revolutions) to obtain the reference internal pressure. Then, control device 70 obtains a third pressure deviation (=acquired crankcase internal pressure−reference internal pressure), which is the difference between the acquired crankcase internal pressure and the reference internal pressure, and advances the process to step SE135.

The control device 70 (CPU 71) executing the processing of step SE130 sets the operating state of the internal combustion engine to a predetermined operating state (idling state) after the foreign matter removing operation mode by the foreign matter removing operation execution unit 71I (see FIG. 1) ends. ) and acquires the crankcase internal pressure, which is the pressure in the crankcase of the internal combustion engine, for a third predetermined time period (see FIG. 1). It should be noted that when the internal combustion engine is brought into the predetermined operating state, it may be in an operating state other than the idling state.

At step SE135, the control device 70 determines whether or not the third pressure deviation is equal to or greater than the third abnormality determination pressure. If the third pressure deviation is less than the third abnormality determination pressure (No), the process proceeds to step SE145.

Note that the third abnormality determination pressure is set to an appropriate value that enables abnormality to be determined in an idling state based on an actual vehicle, simulation, or the like.

When the process proceeds to step SE140, the control device 70 sets the post-removal foreign matter presence flag to ON, and proceeds to step SE145. In the example of FIG. 28, the post-removal foreign matter presence flag is set to ON when the third pressure deviation exceeds the third abnormality determination pressure even once. It is also possible to obtain the number of times that the pressure is determined to be equal to or greater than 3 abnormal determination pressures, and to set the post-removal foreign matter flag to ON when the number of determinations is equal to or greater than a predetermined number of times.

The control device 70 (CPU 71) executing the processes of steps SE130 to SE140 controls the abnormality detection section 71D (see FIG. 1) to correspond to the acquisition of the crankcase internal pressure by the third crankcase internal pressure acquisition section 71J (see FIG. 1). ) and detects the presence or absence of deposits of foreign matter around the piston ring of the internal combustion engine (see FIG. 1).

When the process proceeds to step SE145, the control device 70 determines whether or not the elapsed time measured by the timer is equal to or longer than the third predetermined time. The process proceeds, and if it is less than the third predetermined time (No), the process shown in FIG. 28 ends. After completing the process of FIG. 28, the control device 70 advances the process to step S075 shown in FIG. Note that the value of the third predetermined time is appropriately set, and is, for example, about several tens [sec] to several [min], as in the first embodiment.

In step SE150, control device 70 stops the operation of the timer (stops measuring the elapsed time) and advances the process to step SE155.

In step SE155, control device 70 determines whether or not the post-removal foreign matter flag is ON. If the post-removal foreign matter flag is ON (Yes), the process proceeds to step SE160A, and the post-removal foreign matter flag is set to ON. If not ON (No), the process proceeds to step SE160B.

When proceeding to step SE160A, control device 70 sets the removal completion flag to OFF and advances the process to step SE165.

When proceeding to step SE160B, control device 70 sets the removal completion flag to ON and advances the process to step SE165.

When the process proceeds to step SE165, the control device 70 sets the post-removal confirmation flag to ON, and ends the process shown in FIG. After completing the process of FIG. 28, the control device 70 advances the process to step S075 shown in FIG.

In the second embodiment, compared to the first embodiment in which the crankcase internal pressure is classified into groups and averaged, it is possible to simplify the abnormality determination using the crankcase internal pressure.

The control device for an internal combustion engine of the present invention is not limited to the configuration, structure, processing procedure, operation, etc., described in the present embodiment, and various changes, additions, and deletions are possible without changing the gist of the present invention. be. Moreover, the internal combustion engine system is not limited to the example shown in FIG. 1, and can be applied to various internal combustion engine systems.

In the description of the present embodiment, an internal combustion engine system having two turbochargers, a first turbocharger and a second turbocharger, has been described as an example. It is applicable to an internal combustion engine having three or more superchargers and an internal combustion engine having no supercharger. Further, in the description of the present embodiment, an example of a configuration in which the first turbocharger and the second turbocharger supercharge in parallel (a configuration in which supercharging can be performed in series) has been described. The present invention can be applied to a configuration in which the superchargers supercharge in parallel or supercharge in series.

In the description of the present embodiment, an example of performing fuel sweep (gentle sweep) increase/decrease control (1) and fuel sweep (rapid sweep) increase/decrease control (2) has been described. good. Also, as the piston swing control, an example of performing boost pressure/exhaust pressure step increase/decrease control, fuel injection timing step advance/retard control, and fuel step increase/decrease control has been described. You can do it.

Also, the numerical values used in the description of the present embodiment are examples, and the present invention is not limited to these numerical values. Greater than (≧), less than (≦), greater than (>), less than (<), etc. may or may not include an equal sign.

1 Internal Combustion Engine System 10 Internal Combustion Engine 10A Cylinder Head 10B Cylinder 10BJ Cylinder Center Axis 10C Crankcase 10D Oil Pan 10E Crankshaft 10F Piston 10F1, 10F2 Ring Groove 10FJ Piston Center Axis 10G1, 10G2 Piston Ring 10GA, 10GB Joint Gap 10H Piston Pin 10 M. Connecting rod 10N Combustion chamber 10S Gasket 11A, 11B1, 11B2, 11C1, 11C2, 11D Intake pipe 11CB Intake bypass pipe 11E Intake manifold 12A1, 12A2 Exhaust manifold 12B1, 12B2, 12C1, 12C2 Exhaust pipe 12BB Exhaust bypass pipe 13A Blow-by gas pipe 13B Blowby Gas path 13C, 13D Gas passage 21 Intake flow rate detection means 22A Boost pressure detection means 22B Exhaust pressure detection means 22C Differential pressure detection means 22D Atmospheric pressure detection means 22E Intake temperature detection means 22F, 22G Exhaust pressure detection means 22H Vehicle speed detection means 22K parking brake detection means 22N shift range detection means 22P pressure detection means 22S foreign object removal operation instruction input means 22Y oil temperature detection means 24 coolant temperature detection means 25 rotation detection means 26 exhaust temperature detection means 27 accelerator pedal depression amount detection means 31 first Turbocharger 31A, 32A Compressor 31B, 32B Turbine 31C, 32C Variable nozzle 31D, 32D Nozzle drive means 31E, 32E Nozzle opening detection means 32 Second supercharger 41 Fuel pressure adjustment pump 45 Notification means 51 Oxidation catalyst 52 DPF
53 Urea SCR
61 intake bypass valve (switching means)
62 Intake switching valve (switching means)
63 Exhaust switching valve (switching means)
70 control device 71 CPU
71A Operating state detection unit 71B Detection condition determination unit 71C First crankcase internal pressure acquisition unit 71D Abnormality detection unit 71E Re-detection condition determination unit 71F Second crankcase internal pressure acquisition unit 71G Abnormal re-detection unit 71H Abnormal confirmation determination unit 71I Foreign matter removal operation Execution unit 71J Third crankcase internal pressure acquisition unit 71K Foreign matter removal confirmation unit 71L Foreign matter removal operation result notification unit 73 Storage means

Claims (14)

A control device for an internal combustion engine that detects the presence or absence of deposits of foreign matter around a piston ring of the internal combustion engine,
The control device is
an operating state detection unit that detects an operating state of the internal combustion engine;
a first crankcase internal pressure obtaining unit for obtaining, for a first predetermined time, the crankcase internal pressure, which is the pressure within the crankcase of the internal combustion engine, which is one of the operating states;
The piston ring gradually turns with respect to the piston, and the position of the abutment gap, which is a gap in the circumferential direction of the C-ring-shaped piston ring, coincides with the position of the foreign object; When the position and the position of the foreign object do not match, and based on the change in the crankcase internal pressure caused by the amount of blow-by gas that changes with the change in the state of communication between the combustion chamber and the inside of the crankcase. , when a pressure step is detected as a step-like fluctuation amount of the acquired crankcase internal pressure, based on the presence or absence of an abnormal step that is a pressure step larger than the abnormal step pressure set as a threshold value for abnormality determination, the above an abnormality detection unit that detects whether or not the foreign matter is deposited around the piston ring of the internal combustion engine;
has
The control device, in the abnormality detection unit,
classifying the obtained plurality of crankcase internal pressures into a plurality of data groups,
calculating the mean pressure for each said data group;
determining that the abnormal step exists when the difference between the average pressures of the adjacent data groups is greater than the abnormal step pressure;
A control device for an internal combustion engine. A control device for an internal combustion engine that detects the presence or absence of deposits of foreign matter around a piston ring of the internal combustion engine,
The control device includes a reference crank in which a reference internal pressure, which is a reference pressure in the crankcase when the foreign matter is not accumulated around the piston ring, is set according to the operating state of the internal combustion engine. The internal pressure characteristics of the case are memorized,
The control device is
an operating state detection unit that detects the operating state of the internal combustion engine;
a first crankcase internal pressure obtaining unit for obtaining, for a first predetermined time, the crankcase internal pressure, which is the pressure within the crankcase of the internal combustion engine, which is one of the operating states;
The piston ring gradually turns with respect to the piston, and the position of the abutment gap, which is a gap in the circumferential direction of the C-ring-shaped piston ring, coincides with the position of the foreign object; When the position and the position of the foreign object do not match, and based on the change in the crankcase internal pressure caused by the amount of blow-by gas that changes with the change in the state of communication between the combustion chamber and the inside of the crankcase. a pressure deviation, which is a deviation between the obtained crankcase internal pressure and the reference internal pressure obtained based on the operating state and the reference crankcase internal pressure characteristic, is obtained, and the pressure deviation is equal to or higher than the abnormality determination pressure set as the abnormality determination threshold. an abnormality detection unit that detects the presence or absence of deposition of the foreign matter around the piston ring of the internal combustion engine based on the presence or absence of the pressure deviation that becomes
has
The control device is
If the operating state of the internal combustion engine is not idling,
The reference internal pressure obtained based on the operating state of the internal combustion engine when the pressure deviation was obtained and the reference crankcase internal pressure characteristics, the operating state when the internal combustion engine is in the idling state, and the reference crankcase. executing the abnormality detection unit with a value set to be less than half of the pressure difference between the reference internal pressure in the idling state obtained based on the internal pressure characteristic and the abnormality determination pressure,
When the operating state of the internal combustion engine is the idling state,
not executing the abnormality detection unit, or executing the abnormality detection unit using a preset value as the abnormality determination pressure;
A control device for an internal combustion engine. The control device for an internal combustion engine according to claim 1 or 2,
The control device is
Acquiring the internal pressure of the crankcase using a pressure detection means provided in a blow-by gas path that guides blow-by gas in the crankcase of the internal combustion engine to an intake path of the internal combustion engine;
A control device for an internal combustion engine. A control device for an internal combustion engine according to any one of claims 1 to 3 ,
The control device is
A second crankcase internal pressure acquisition for acquiring the crankcase internal pressure for a second predetermined time when the abnormality detection unit detects that the foreign matter is deposited around the piston ring of the internal combustion engine. Department and
an abnormality re-detection unit that executes the processing of the abnormality detection unit in correspondence with acquisition of the crankcase internal pressure by the second crankcase internal pressure acquisition unit;
When the abnormality re-detection unit again detects that there is accumulation of the foreign matter around the piston ring of the internal combustion engine, there is accumulation of the foreign matter around the piston ring of the internal combustion engine. and an abnormality determination determination unit that determines determination,
having
A control device for an internal combustion engine. A control device for an internal combustion engine according to claim 4 ,
The internal combustion engine is mounted on a vehicle,
The vehicle is provided with notification means,
The control device is
When the confirmation determination is made by the abnormality confirmation determination unit, using the notification means to notify that there is deposition of the foreign matter around the piston ring of the internal combustion engine;
A control device for an internal combustion engine. A control device for an internal combustion engine according to claim 5 ,
The control device has a foreign matter removal operation execution unit capable of executing a foreign matter removal operation mode for removing the foreign matter deposited around the piston ring of the internal combustion engine,
The vehicle includes:
foreign matter removing operation instruction input means for enabling an instruction to start the foreign matter removing operation mode when the confirmation determination is made;
A control device for an internal combustion engine. A control device for an internal combustion engine according to claim 6 ,
The control device is
When the foreign matter removing operation execution unit executes the foreign matter removing operation mode, the notifying means indicates whether or not the foreign matter deposited around the piston ring of the internal combustion engine has been removed as a result of execution. to notify using
A control device for an internal combustion engine. A control device for an internal combustion engine according to claim 7 ,
The control device is
the foreign matter removing operation executing unit that executes the foreign matter removing operation mode when an instruction to start the foreign matter removing operation mode is given from the foreign matter removing operation instruction input means;
A third crankcase internal pressure acquisition unit configured to acquire the crankcase internal pressure for a third predetermined period of time after the foreign object removal operation mode by the foreign object removal operation execution unit is completed, by setting the operating state of the internal combustion engine to a predetermined operation state. and,
executing the processing of the abnormality detection unit corresponding to the acquisition of the crankcase internal pressure by the third crankcase internal pressure acquisition unit, and detecting the presence or absence of deposition of the foreign matter around the piston ring of the internal combustion engine; a foreign matter removal confirmation unit;
having
A control device for an internal combustion engine. A control device for an internal combustion engine according to claim 8 ,
The control device is
When the foreign matter removal confirmation unit detects that the foreign matter has not accumulated around the piston ring of the internal combustion engine, the notifying means is used to notify that the removal of the foreign matter has been completed. When the removal confirmation unit detects that there is accumulation of the foreign matter around the piston ring of the internal combustion engine, the notification means is used to notify the customer to bring the vehicle to a shop for foreign matter removal. having an operation result notification unit;
A control device for an internal combustion engine. The control device for an internal combustion engine according to any one of claims 6 to 9 ,
The control device is
In the foreign object removal operation mode,
fuel sweep increase control for gradually increasing the amount of fuel injection for a predetermined period of time to promote moistening of the foreign object;
fuel sweep reduction control for gradually reducing the amount of fuel injection for a predetermined period of time to promote drying of the moistened foreign matter;
is repeated a predetermined number of times to promote peeling of the foreign matter around the piston ring;
A control device for an internal combustion engine. A control device for an internal combustion engine according to claim 10 ,
The fuel injection amount reduced by the fuel sweep reduction control is set so as to reduce the fuel injection amount until the temperature of the piston of the internal combustion engine reaches 300 ° C. or higher.
A control device for an internal combustion engine. The control device for an internal combustion engine according to any one of claims 6 to 11 ,
The control device is
In the foreign object removal operation mode,
executing piston swing control in which the piston center axis, which is the center axis of the piston of the internal combustion engine, swings with respect to the cylinder center axis, which is the center axis of the cylinder of the internal combustion engine;
A control device for an internal combustion engine. A control device for an internal combustion engine according to claim 12 ,
The piston swing control is
At least one of fuel injection timing step advance/retard control for repeating stepwise advance and retard of the fuel injection timing and fuel step increase/decrease control for repeating stepwise increase and decrease of the fuel injection amount. be,
A control device for an internal combustion engine. A control device for an internal combustion engine according to claim 12 ,
The internal combustion engine has a supercharger,
The piston swing control is
Fuel injection timing step advance/retard control that repeats stepwise advance and retard of fuel injection timing, fuel step increase/decrease control that repeats stepwise increase and decrease of fuel injection amount, boost pressure or exhaust at least one of boost pressure/exhaust pressure step increase/decrease control in which the manifold internal pressure is repeatedly increased and decreased in steps,
A control device for an internal combustion engine.

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