JP4019483B2 - Abnormality judgment device for variable capacity turbocharger - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an abnormality determination device for a variable displacement turbocharger that determines whether or not an abnormality has occurred in a variable displacement turbocharger mounted on an internal combustion engine.
[0002]
[Prior art]
In general, in order to improve engine output, it is desirable to increase the amount of air charged in the combustion chamber. Therefore, a supercharging system that not only fills the combustion chamber with air due to the negative pressure generated in the combustion chamber as the piston moves, but also forcibly sends air from the outside into the combustion chamber to increase the efficiency of filling the air in the combustion chamber. Is in practical use. As such a supercharging system, a turbocharger is widely known.
[0003]
The turbocharger includes a turbine wheel that is rotated by exhaust gas sent out from the combustion chamber, and a compressor wheel that forcibly feeds air into the combustion chamber. The turbine wheel and the compressor wheel are connected to each other by a rotor shaft so as to be integrally rotatable. When exhaust gas is blown onto the turbine wheel and the wheel rotates, the rotation is transmitted to the compressor wheel by the rotor shaft. As the compressor wheel rotates in this way, air is forced into the combustion chamber.
[0004]
On the other hand, in such a turbocharger, it is desirable that the pressure of the air fed into the combustion chamber, that is, the supercharging pressure, be adjusted as appropriate according to the operating conditions of the engine. Therefore, in recent years, a variable capacity turbocharger in which the supercharging pressure is variable by adjusting the flow rate and flow velocity of exhaust gas blown to the turbine wheel has been proposed and put into practical use.
[0005]
Some of these variable capacity turbochargers change the flow rate of the exhaust gas by changing the area of the flow path of the exhaust gas blown to the turbine wheel. In such a variable displacement turbocharger, for example, a nozzle vane that is movable by a fluid pressure such as a negative pressure is provided at a turbine inlet portion, and a variable displacement mechanism that makes the area of the inlet portion variable is provided. During low-speed or low-load operation where there is little exhaust gas and the supercharging effect due to gas volume is not significant, the opening of the nozzle is reduced to reduce the area of the turbine inlet, and the flow rate of exhaust gas blown to the turbine wheel is reduced. Increase. Thus, the supercharging effect by the gas dynamic pressure is improved by increasing the flow rate of the exhaust gas. On the other hand, during high-speed or high-load operation where the amount of exhaust gas is large and the supercharging effect due to gas volume can be sufficiently expected, the opening of the nozzle is increased so as to increase the area of the turbine inlet, and the flow resistance of the exhaust gas is reduced. Decrease. By reducing the flow resistance of the exhaust gas, the exhaust efficiency of the engine can be increased.
[0006]
[Problems to be solved by the invention]
By the way, in the variable capacity type turbocharger as described above, when the operation as the variable capacity mechanism becomes impossible due to the sticking (fixing) of the nozzle vanes or the like, the supercharging pressure cannot be adjusted according to the operating condition of the engine.
[0007]
For example, if the nozzle vane is fixed while the nozzle opening is set to a large value at the time of low speed or low load operation or the like, the flow rate of the exhaust gas blown to the turbine wheel does not increase, and the supercharging effect cannot be expected so much.
[0008]
On the other hand, if the nozzle vane is fixed while the opening of the nozzle is set to a small value at high speed or high load operation, the exhaust efficiency decreases due to the flow resistance of the exhaust gas, which in turn leads to a decrease in engine output. .
[0009]
Therefore, conventionally, in order to cope with such problems, the above-described abnormality of the variable capacity turbocharger is detected based on the supercharging pressure, and when the abnormality is detected, the variable capacity mechanism is forcibly opened. An apparatus for recovering the device has also been proposed (for example, see Japanese Patent Application Laid-Open No. 61-190124).
[0010]
However, in the device described in the above publication, if the actuator itself constituting the variable displacement mechanism or its control system becomes abnormal, or if the control valve corresponding to the nozzle vane is fixed, the device is the same. The operation of the variable capacity mechanism itself becomes difficult, and even the recovery thereof becomes difficult. Moreover, unless the supercharging pressure actually becomes an abnormal value, the occurrence of the abnormality cannot be determined.
[0011]
The present invention has been made in view of such circumstances, and an object thereof is to provide an abnormality determination device for a variable capacity turbocharger that can more easily and reliably determine whether or not an abnormality has occurred. is there.
[0012]
[Means for Solving the Problems]
  According to the first aspect of the present invention, the operation of the variable displacement mechanism is performed by the pressure-driven actuator while supercharging the air sucked into the combustion chamber of the engine by operating based on the exhaust gas flow from the internal combustion engine. An abnormality determination device for a variable capacity turbocharger whose operation amount is controlled through the pressure detection means for detecting the actuator drive pressure, and the actuator drive pressure detected by the pressure detection means should be saturated Based on the time to reach the appropriate saturation negative pressure value,pluralAbnormalContents ofAn abnormality determination means for determiningThe plurality of abnormalities are detected more than the shortest saturation time, which is the shortest time until the detected actuator driving pressure reaches the appropriate saturated negative pressure value in accordance with the normal operation of the turbocharger. Includes abnormalities when the time required for the actuator drive pressure to reach the appropriate saturation negative pressure value is earlyThis is the gist.
[0013]
According to the configuration of the first aspect of the present invention, the abnormality of the variable capacity turbocharger is detected not by the supercharging pressure of the turbocharger but by the driving pressure of the actuator that operates the variable capacity mechanism. Therefore, it is possible to easily determine whether there is an abnormality in the turbocharger without operating the internal combustion engine and generating supercharging pressure.
[0017]
  For example, in a turbocharger in which a stick (sticking) has occurred in the movable part of the variable capacity mechanism, the negative pressure that is the driving pressure of the actuator that operates the variable capacity mechanism has exceeded the negative pressure value that should be saturated once. Later, it gradually converges to the same negative pressure value. In addition, when the variable capacity mechanism is configured with a diaphragm or the like, the time for the negative pressure to reach a predetermined pressure such as a saturation pressure naturally varies depending on symptoms such as leakage or tearing. It is generated in the variable capacity mechanism by grasping the characteristics of the negative pressure value transition of the actuator driving pressure.pluralAbnormal contentTheCan be determined.
  The invention described in claim 2A variable in which the amount of operation is controlled through operation of a variable displacement mechanism by a pressure-driven actuator while supercharging air sucked into a combustion chamber of the engine by operating based on an exhaust gas flow from the internal combustion engine An abnormality determination device for a capacity-type turbocharger,Joint for connecting the actuator and the variable capacity mechanismAnd an abnormality of the turbocharger based on a time until the actuator driving pressure detected by the pressure detecting means reaches an appropriate saturation negative pressure value to be saturated. An abnormality determining means for determining the presence or absence ofThe abnormality determination means is associated with normal operation of the turbocharger.The detected actuator driving pressure isThe time until the detected drive pressure of the actuator reaches the appropriate saturation negative pressure value is shorter than the shortest saturation time that is the shortest time until the appropriate saturation negative pressure value is reached.EarlyThe gist is that it is determined that the wear abnormality has occurred in the joint.
According to the third aspect of the present invention, the operation of the variable displacement mechanism is performed by the pressure-driven actuator while supercharging the air sucked into the combustion chamber of the engine by operating based on the exhaust gas flow from the internal combustion engine. The variable capacity turbocharger abnormality determination device whose operation amount is controlled through the turbine, and the variable capacity mechanism includes a turbine wheel and a nozzle vane that changes a flow rate of exhaust gas blown to the turbine wheel by opening and closing drive. A pressure detecting means for detecting the driving pressure of the actuator, and an abnormality of the turbocharger based on a time until the driving pressure of the actuator detected by the pressure detecting means reaches an appropriate saturation negative pressure value to be saturated Abnormality determining means for determining the presence or absence of occurrence, the abnormality determining means The detected drive pressure of the actuator is less than the minimum saturation time, which is the shortest time until the detected drive pressure of the actuator reaches the appropriate saturated negative pressure value due to normal operation of the charger. When the time to reach the pressure value is early, the detected actuator driving pressure is compared with a reference pressure set in advance for the driving pressure, and the nozzle vane has a stick abnormality based on the comparison result. The gist is that it is determined that it has occurred.
  Claim4The invention described inIn the invention according to any one of claims 1 to 3,The abnormality determination means determines that the time required for the detected actuator driving pressure to reach the appropriate saturation negative pressure value is determined so that the detected actuator driving pressure with the normal operation of the turbocharger is the appropriate saturation. When the actuator is between the longest saturation time, which is the longest time until the negative pressure value is reached, and a predetermined threshold time in a range larger than the longest saturation time, the actuator has a little negative pressure loss. The gist of this is that it is determined that not many leakage abnormalities have occurred.
  Claim5The invention described inIn the invention according to any one of claims 1 to 4,The abnormality determination means is longer than the longest saturation time from the longest saturation time that is the longest time until the detected actuator driving pressure reaches the appropriate saturation negative pressure value with the normal operation of the turbocharger. If the detected actuator drive pressure does not reach the appropriate saturated negative pressure value even after a predetermined threshold time in the range, the actuator has a breakage abnormality with a large negative pressure loss. The gist is that it is to be judged.
[0018]
  Claim6The gist of the invention described in is that the abnormality determination means makes the determination by performing a test drive of the actuator at least one of when the internal combustion engine is stopped and started.
[0019]
  Claim6According to the configuration of the invention described above, since it is possible to determine whether or not an abnormality of the turbocharger occurs other than during the operation of the internal combustion engine, it is possible to prevent the abnormality from occurring during the operation of the internal combustion engine.
[0020]
  Claim7The gist of the invention described in is that the abnormality determination means performs the determination by performing a test drive of the actuator during idling of the internal combustion engine.
[0021]
According to an eighth aspect of the present invention, the operation of the variable displacement mechanism is performed by a pressure-driven actuator while supercharging the air sucked into the combustion chamber of the engine by operating based on the exhaust gas flow from the internal combustion engine. An abnormality determination device for a variable capacity turbocharger whose operation amount is controlled through the pressure detection means for detecting the actuator drive pressure, and the actuator drive pressure detected by the pressure detection means should be saturated Abnormality determining means for determining whether or not the turbocharger is abnormal based on the time until the appropriate saturated negative pressure value is reached, the abnormality determining means test-drives the actuator during idling of the internal combustion engine. The gist is that the determination is performed.
  Claim 7Or 8According to the configuration of the invention described in (1), it is possible to determine whether or not an abnormality has occurred without affecting the characteristics of the operating internal combustion engine.
  Claim9The invention described in claim 18The variable capacity type turbocharger abnormality determination device according to any one of the above, further includes alarm means for appropriately warning an abnormality determination result by the abnormality determination means.
[0022]
  Claim9According to the configuration of the invention described in (3), it is possible to accurately notify the driver of the abnormality occurring in the variable capacity turbocharger or the cause thereof by the warning means.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a variable capacity turbocharger abnormality determination device according to the present invention will be described in detail.
[0024]
FIG. 1 shows the configuration of a diesel engine equipped with a variable capacity turbocharger and its intake / exhaust system. A piston 12 is provided in the cylinder block 11a of the diesel engine 11 so as to be able to reciprocate. The piston 12 is connected via a connecting rod 13 to a crankshaft (output shaft) 14 provided at the lower part of the diesel engine 11. The reciprocating motion of the piston 12 is converted into the rotational motion of the crankshaft 14 by the connecting rod 13.
[0025]
A signal rotor 15 is attached to the crankshaft 14. A plurality of protrusions are provided on the outer peripheral surface of the signal rotor 15 at equal angles with the axis of the crankshaft 14 as the center. A crank position sensor 16 that detects this protrusion and outputs a detection signal is provided on the side of the signal rotor 15. When the crankshaft 14 rotates, each projection of the signal rotor 15 sequentially passes the side of the crank position sensor 16. At this time, the sensor 16 outputs a pulsed detection signal corresponding to each protrusion.
[0026]
The rotational movement of the crankshaft 14 is also transmitted to the vacuum pump 91. The vacuum pump 91 driven by this rotational movement sucks out air inside the vacuum tank 102 connected to the vacuum pump 91 and maintains the inside of the vacuum tank 102 at a constant negative pressure.
[0027]
A cylinder head 17 is provided at the upper end of the cylinder block 11a. A combustion chamber 18 is formed by a space surrounded by the inner peripheral side surface of the cylinder head 17 and the upper end surface of the piston 12. The cylinder head 17 is provided with a fuel injection nozzle 18 a for injecting fuel into the combustion chamber 18. Further, an intake port 19 and an exhaust port 20 are formed in the cylinder head 17 so as to communicate with the combustion chamber 18. The intake port 19 and the exhaust port 20 are provided with an intake valve 21 and an exhaust valve 22, respectively.
[0028]
An intake camshaft 23 and an exhaust camshaft 24 for opening and closing the intake valve 21 and the exhaust valve 22 are provided on the cylinder head 17. These intake / exhaust camshafts 23 and 24 are drivingly connected to the crankshaft 14 by a timing belt (not shown). The intake valve 21 is opened and closed by the rotation of the intake camshaft 23 based on the rotation of the crankshaft 14, whereby the intake port 19 and the combustion chamber 18 are communicated and disconnected. Similarly, when the exhaust valve 22 is driven to open and close by the rotation of the exhaust camshaft 24, the exhaust port 20 and the combustion chamber 18 are communicated and disconnected.
[0029]
An intake pipe 30 and an exhaust pipe 31 are connected to the intake port 19 and the exhaust port 20, respectively. An intake passage 32 is formed in the intake port 19 and the intake pipe 30. Similarly, an exhaust passage 33 is formed in the exhaust port 20 and the exhaust pipe 31. The upstream portion of the intake passage 32 and the downstream portion of the exhaust passage 33 are each connected to a turbocharger 35. The turbocharger 35 includes a compressor wheel 36 for pressurizing and discharging air to the downstream side of the intake passage 32, and a turbine wheel 37 that rotates by blowing exhaust gas that passes through the exhaust passage 33. The compressor wheel 36 and the turbine wheel 37 are connected by a rotor shaft 38, and the two wheels 36 and 37 are integrally rotated based on the exhaust gas blowing.
[0030]
The exhaust passage 33 is provided with a wastegate 51 that communicates the upstream side and the downstream side of the turbine wheel 37. A wastegate valve 52 that is opened and closed by a valve actuator 53 is provided at an upstream port of the wastegate 51. By opening and closing the waste gate valve 52, the upstream side and the downstream side of the turbine wheel 37 in the exhaust passage 33 are communicated and blocked. When the wastegate valve 52 is opened, a part of the exhaust gas flowing in the exhaust passage 33 is bypassed through the wastegate 51, so that the amount of exhaust gas blown to the turbine wheel 37 is reduced.
[0031]
The intake passage 32 is provided with a pressure sensor 30a for detecting a supercharging pressure (intake pressure). This supercharging pressure detection pressure sensor 30 a detects the pressure of air in the intake passage 32, that is, the supercharging pressure, and a detection signal corresponding to the detected pressure is sent to an electronic control unit (hereinafter referred to as “ECU”) 92. Output for.
[0032]
On the other hand, the crankshaft 14 of the diesel engine 11 is drivingly connected to the drive shaft 41 a of the fuel injection pump 41. The fuel injection pump 41 is connected to the fuel injection nozzle 18a via the fuel line 42. The fuel injection pump 41 is driven by the rotation of the crankshaft 14 being transmitted to the drive shaft 41a. The fuel pump 41 sucks fuel from a fuel tank (not shown) and pressurizes and discharges this fuel toward the fuel injection nozzle 18a. The fuel injection nozzle 18 a is operated by the pressure of the fuel fed from the fuel injection pump 41 and injects the fuel into the combustion chamber 18.
[0033]
The fuel injection pump 41 further includes an electromagnetic spill valve 43 that adjusts the amount of fuel discharged toward the injection nozzle 18a and a timer device 44 that adjusts the fuel discharge start timing. By adjusting the electromagnetic spill valve 43 and the timer device 44, the amount of fuel injected into the combustion chamber 18 and the injection timing thereof are adjusted.
[0034]
Incidentally, the accelerator pedal 34 is provided with an accelerator sensor 34a for detecting the amount of depression. The accelerator sensor 34a outputs a detection signal corresponding to the detected depression amount of the accelerator pedal 34 to the ECU 92.
[0035]
In such an engine system, the exhaust gas discharged from the combustion chamber 18 is blown to the turbine wheel 37 of the turbocharger 35 through the exhaust passage 33. The turbine wheel 37 is rotated by blowing the exhaust gas. The rotation of the turbine wheel 37 is transmitted to the compressor wheel 36 via the rotor shaft 38, and the compressor wheel 36 is also rotated. When the compressor wheel 36 rotates in this manner, the air is pressurized and forced out toward the downstream side of the intake passage 32. As a result, the amount of air taken into the combustion chamber 18 increases. As the amount of air in the combustion chamber 18 increases, the amount of fuel combustible in the combustion chamber 18 also increases. Thus, the efficiency of filling the air and fuel in the combustion chamber 18 is increased, so that the output of the engine 11 can be improved.
[0036]
Next, a specific configuration of the turbocharger 35 will be described in detail.
FIG. 2 shows a side sectional structure of the turbocharger 35. The turbocharger 35 includes a center housing 61, a compressor housing 62, and a turbine housing 63. The center housing 61 supports the rotor shaft 38 so as to be rotatable about its axis. The compressor wheel 36 having a plurality of blades 36 a is attached to one end (right end in the figure) of the rotor shaft 38. On the other hand, the turbine wheel 37 having a plurality of blades 37a is similarly attached to the other end (left end in the figure) of the rotor shaft 38.
[0037]
A compressor housing 62 is attached to one end side of the center housing 61 so as to surround the outer periphery of the compressor wheel 36. In the compressor housing 62, an intake inlet 62 a having a circular cross section centering on the axis of the rotor shaft 38 is opened on the opposite side of the center housing 61. Air is introduced into the compressor housing 62 through the intake inlet 62a. In addition, a compressor passage 64 that spirally extends around the outer periphery of the compressor wheel 36 is formed inside the housing 62. The compressor passage 64 communicates with the intake passage 32 (FIG. 1). The air introduced from the intake inlet 62a is forcibly sent to the combustion chamber 18 through the passage 32 as the compressor wheel 36 rotates.
[0038]
On the other hand, the turbine housing 63 is attached to the other end of the center housing 61 so as to surround the outer periphery of the turbine wheel 37. In the turbine housing 63, a scroll passage 66 that extends in a spiral shape on the outer periphery of the turbine wheel 37 is formed. The scroll passage 66 communicates with the exhaust passage 33 (FIG. 1). Exhaust gas sent out from the combustion chamber 18 is introduced into the scroll passage 66 through the exhaust passage 33.
[0039]
Further, an exhaust gas passage 67 for sending the exhaust gas in the passage 66 to the turbine wheel 37 is provided on the inner periphery of the scroll passage 66. The exhaust gas sent from the exhaust gas passage 67 is blown to the blades 37 a of the turbine wheel 37, so that the wheel 37 rotates about the axis of the rotor shaft 38. The exhaust gas blown to the turbine wheel 37 is sent out to an unillustrated catalytic converter from an exhaust outlet 63a provided on the turbine housing 63 on the opposite side of the center housing 61.
[0040]
Next, the variable nozzle mechanism 71 that makes the flow rate of the exhaust gas blown to the turbine wheel 37 through the exhaust gas passage 67 variable will be described.
FIG. 3A shows a side sectional structure of the mechanism 71, and FIG. 3B shows a front structure of the mechanism 71. The variable nozzle mechanism 71 is provided so as to be sandwiched between the center housing 61 and the turbine housing 63. As shown in FIG. 3A, the variable nozzle mechanism 71 includes a ring-shaped nozzle back plate 72. The nozzle back plate 72 is provided with a plurality of shafts 73 at equal angles around the center of the plate 72. These shafts 73 are rotatably supported by penetrating the nozzle back plate 72 in the thickness direction. Further, a nozzle vane 74 is fixed to one end of these shafts 73 (the left end in FIG. 3A). An opening / closing lever 75 is provided at the other end of the shaft 73 and extends in the direction of the outer edge of the nozzle back plate 72 at right angles to the same axis. A pair of sandwiching portions 75a branched into two forks is formed at the tip of the opening / closing lever 75.
[0041]
An annular ring plate 76 is provided so as to be sandwiched between each open / close lever 75 and the nozzle back plate 72. The ring plate 76 is rotatable around a circular center. Further, the ring plate 76 is provided with a plurality of pins 77 at equal angles around the center of the circle. These pins 77 are sandwiched between the holding portions 75a of the opening / closing lever 75, and support the opening / closing lever 75 in a rotatable manner.
[0042]
When the ring plate 76 is rotated around the center of the circle, each pin 77 pushes the holding portion 75a in the rotation direction. As a result, the opening / closing lever 75 rotates the shaft 73. As the shaft 73 rotates, each nozzle vane 74 also rotates about the axis line of the coaxial 73. By such a mechanism, each nozzle vane 74 can be rotated in a synchronized state. Further, the size of the gap between the adjacent nozzle vanes 74 is adjusted by the rotation of the nozzle vanes 74.
[0043]
The variable nozzle mechanism 71 described above is fixed in a manner shown in FIG. 2 by fastening the nozzle back plate 72 and the turbine housing 63 with bolts (not shown). By fixing in this way, the nozzle vane 74 is disposed in the exhaust gas passage 67.
[0044]
On the other hand, a drive pin 86 is provided on the outer edge of the ring plate 76 and extends in parallel with the rotation center axis of the plate 76. A driving mechanism 82 (see FIG. 2) for driving the variable nozzle mechanism 71 is connected to the driving pin 86.
[0045]
The drive mechanism 82 shown in FIG. 2 includes a support shaft 83 that is rotatably supported by the center housing 61. A drive lever 84 is fixed to one end (left end in the figure) of the support shaft 83. The driving pin 86 is rotatably connected to the tip of the driving lever 84.
[0046]
Further, an operation piece 85 connected to the actuator 87 via a link 88c and a rod 88b described later is fixed to the other end (right end in the figure) of the support shaft 83. When the operating piece 85 is operated by driving the actuator 87, the support shaft 83 rotates. As the support shaft 83 rotates, the drive lever 84 also rotates about the support shaft 83. As a result, the pin 86 is pushed by the drive lever 84, and the ring plate 76 rotates about its rotation axis. By rotating the ring plate 76 in this way, the nozzle vane 74 is driven to open and close.
[0047]
The flow rate of the exhaust gas blown to the turbine wheel 37 is changed by the opening / closing drive of the nozzle vane 74, and the rotation speeds of the turbine wheel 37, the rotor shaft 38, and the compressor wheel 36 are changed. Due to the change in the rotational speed, the amount of air sent out by the compressor wheel 36 changes. Therefore, the supercharging amount of the air fed into the combustion chamber 18 can be adjusted by controlling the opening and closing of the nozzle vane 74.
[0048]
Next, the actuator 87 for driving the drive mechanism 82 and its drive device will be described.
FIG. 4 shows the configuration of the actuator 87 and its driving device. The inside of the actuator 87 is partitioned by a diaphragm 88 into a negative pressure chamber 87a and an atmospheric chamber 87b. A coil spring 88a that expands and contracts in a direction orthogonal to the diaphragm 88 is provided inside the negative pressure chamber 87a. A negative pressure passage 89 is connected to the negative pressure chamber 87a. On the other hand, the inside of the atmospheric chamber 87 b communicates with the outside of the actuator 87 and is at atmospheric pressure.
[0049]
The diaphragm 88 is provided with a rod 88 b that extends in the expansion and contraction direction of the coil spring 88 a and protrudes outside the actuator 87. The rod 88b is connected to an operation piece 85 (FIG. 2) provided in a drive mechanism 82 for opening and closing the nozzle vane 74 through a link 88c that is rotatably connected by a joint 103.
[0050]
The negative pressure passage 89 is connected to a vacuum tank 102 via an electric vacuum regulating valve (hereinafter referred to as “EVRV”) 90. An actuator pressure sensor 101 is connected to a negative pressure passage 89 connecting the actuator 87 and the EVRV 90.
[0051]
The EVRV 90 includes an electromagnetic solenoid (not shown). The current supplied to the electromagnetic solenoid is duty-controlled by the ECU 92, whereby the opening degree of the EVRV 90 is adjusted.
[0052]
When the opening degree of the EVRV 90 is adjusted, the amount of suction by the vacuum tank 102, that is, the amount of negative pressure in the negative pressure chamber 87a is adjusted. As a result, a difference is generated between the pressure in the negative pressure chamber 87a and the pressure in the atmospheric chamber 87b, and the diaphragm 88 is displaced to a position where the pressure difference between the chambers 87a and 87b and the coil spring 88a are balanced. Due to this displacement, the protruding position of the rod 88b provided on the diaphragm 88 is appropriately changed. And the opening degree of the nozzle vane 74 in the turbocharger 35 is adjusted suitably by operating the drive mechanism 82 via the link 88c. Further, by adjusting the opening degree of the nozzle vane 74 in this way, the amount of air forcedly fed into the combustion chamber 18 (FIG. 1) by the turbocharger 35, that is, supercharging of the air supplied to the combustion chamber 18. The pressure will be adjusted. In the present embodiment, the variable nozzle mechanism 71, the drive mechanism 82, and the actuator 87 are collectively referred to as a variable capacity mechanism.
[0053]
Next, the electrical configuration of the diesel engine in the present embodiment will be described with reference to FIG.
This engine system controls the operating amount of the turbocharger 35 through the variable capacity mechanism, including the operating state of the engine 11 such as the fuel injection timing, the fuel injection amount, and the idling speed, and also determines abnormality of the turbocharger. ECU92 for performing is provided. The ECU 92 measures the elapsed time independently of the CPU 94 as a control circuit, the ROM 93, RAM 95 and backup RAM 96 as storage circuits, the external input circuit 98 and external output circuit 99 as input / output circuits, and the program processing. And a timer counter 104 which is a timer circuit that performs the above operation. Each circuit is connected to each other via a bus 97.
[0054]
Next, variable capacity control of the turbocharger 35 performed by the ECU 92 will be described.
The ECU 92 calculates the target value of the supercharging pressure by the turbocharger 35 based on the engine speed, the fuel injection amount, etc., and the ECU 92 detects the supercharging pressure target value and the supercharging pressure detection pressure sensor 30a. Compared with the actual supercharging pressure, the opening degree of the EVRV 90 is controlled. The actuator 87 is driven according to the control of the opening degree of the EVRV 90, and the nozzle vane 74 is driven to open and close.
[0055]
Here, the ROM 93 is a memory for storing various reference data, control programs, maps to be referred to when executing the various control programs, and the like. The CPU 94 executes arithmetic processing based on various control programs and maps stored in the ROM 93. The RAM 95 is a memory for temporarily storing calculation results in the CPU 94, data input from each sensor, and the like. The backup RAM 96 is a non-volatile memory for storing data to be saved when the engine 11 is stopped.
[0056]
The external input circuit 98 is connected to a detection device that detects the operating state of the engine 11, such as the crank position sensor 16, the boost pressure detection pressure sensor 30a, the accelerator sensor 34a, and the actuator pressure sensor 101. On the other hand, the external output circuit 99 is connected to an electromagnetic spill valve 43, a timer device 44, a valve actuator 53, an EVRV 90, an alarm lamp 100, and the like. As the warning lamp 100, a plurality of (four in the present embodiment) warning lamps 100a to 100d that are generated and correspond to various abnormal contents are provided in the driver's seat. These alarm lamps 100a to 100d are turned on when an abnormality occurs in the turbocharger 35 to notify the driver of the occurrence of various abnormalities.
[0057]
Next, an abnormality determination procedure for the turbocharger 35 in the present embodiment will be described. In the present embodiment, as an abnormality of the turbocharger 35, an abnormality caused by sticking (fixing) of the nozzle vane 74 (hereinafter referred to as “stick abnormality”), a rod 88b connecting the nozzle vane 74 and the actuator 87, and a link 88c, Abnormality due to wear of the joint 103 (hereinafter referred to as “wear abnormality”), abnormality due to leakage of the actuator 87 (hereinafter referred to as “leak abnormality”), and abnormality due to breakage of the actuator 87 (hereinafter referred to as “break”). 4 types of abnormalities are assumed.
[0058]
First, the symptom of each part of the turbocharger 35 accompanying the occurrence of each abnormality and the transition of the negative pressure in the negative pressure chamber 87a during the operation will be described with reference to FIGS.
[0059]
First, the symptoms when a stick abnormality occurs in the nozzle vane 74 and the transition of the negative pressure in the negative pressure chamber 87a will be described. When the nozzle vane 74 is brought into a fixed state by the generation of a stick, the rod 88b, the link 88c and the actuator 87 connected to the nozzle vane 74 also stop moving, and the variable displacement mechanism becomes inoperable. Therefore, the volume in the negative pressure chamber 87a of the actuator 87 divided by the diaphragm 88 is also fixed at a constant level. Accordingly, when a negative pressure acts on the negative pressure chamber 87a from the vacuum tank 102 under such a state, the negative pressure in the negative pressure chamber 87a should be saturated as shown by a broken line L1 in FIG. The negative pressure value (hereinafter referred to as “appropriate saturated negative pressure value”) Prf increases rapidly, but immediately converges to the original saturated negative pressure value. Therefore, in the present embodiment, the occurrence of stick abnormality is determined when the difference between the highest negative pressure value that increases rapidly and the original saturated negative pressure value is 6.7 kPa or more.
[0060]
Next, symptoms when abnormal wear occurs in the joint 103 and transition of the negative pressure in the negative pressure chamber 87a will be described. The drive mechanism 82 and the actuator 87 are connected by a rod 88b and a link 88c that are pivotally supported by a joint 103. Therefore, the joint 103 may be worn by repeatedly rotating the actuator 87, and play may occur between the rod 88b and the link 88c. In such a variable displacement mechanism, when the actuator 87 is driven, the transmission of the drag force of the nozzle vane 74 applied to the rod 88b from the link 88c is delayed by the amount of play when the rod 88b moves back and forth, and the original control of the nozzle vane 74 is performed. Can not do. Therefore, in the turbocharger 35 in which the wear abnormality has occurred, the negative pressure in the negative pressure chamber 87a is higher than that in the normal operation shown by the solid line L3 in FIG. The appropriate saturation negative pressure value Prf is reached earlier by the amount of play.
[0061]
Next, the symptom when a leakage abnormality or breakage abnormality occurs in the actuator 87 and the transition of the negative pressure in the negative pressure chamber 87a will be described. If there is a negative pressure drop due to cracks, tears, or damage to the diaphragm 88 of the actuator 87, the negative pressure chamber 87a is immediately saturated even if a negative pressure is applied to the negative pressure chamber 87a from the vacuum tank 102. The negative pressure value Prf does not reach a sufficient negative pressure. Therefore, as indicated by a one-dot chain line L4 or a two-dot chain line L5 in FIG. 6, it takes from the start of applying a negative pressure to the actuator 87 until the negative pressure in the negative pressure chamber 87a reaches the appropriate saturated negative pressure value Prf. The time is longer than that in the normal operation indicated by the solid line L3 in FIG. In the present embodiment, regarding such an abnormality caused by the loss of negative pressure, a leakage abnormality (L4 indicated by a one-dot chain line) is used for a thing with a small amount of removal, and a break abnormality (L5 indicated by a two-dot chain line) for a large one. As distinct. In the case of a break abnormality, the negative pressure may not reach the original appropriate saturation negative pressure value Prf.
[0062]
In the present embodiment, various reference values used for the determination are recorded in advance in the ROM 93 of the ECU 92 in order to determine the various abnormalities as described above from the respective symptoms. As a reference value for determining the negative pressure value, an appropriate saturated negative pressure value Prf is recorded as shown in FIG. Further, as a reference value of time, as shown in FIG. 6, the shortest time (hereinafter, referred to as the time until reaching the appropriate saturated negative pressure value Prf after the operation of the EVRV 90 with the normal operation of the turbocharger 35). Αt and the longest time (hereinafter referred to as “longest saturation time”) βt are recorded. That is, the shortest saturation time αt and the longest saturation time βt respectively indicate the upper limit and the lower limit of the time taken for the inside of the negative pressure chamber 87a to reach the appropriate saturated negative pressure value Prf with the normal operation of the turbocharger 35. Yes.
[0063]
In addition, a threshold time γt is recorded as a reference value for other times. The threshold time γt is a reference value that is predetermined within a range larger than the longest saturation time βt in order to discriminate between the above-described leakage abnormality and breakage abnormality.
[0064]
By setting such a reference value, for example, when the negative pressure value in the negative pressure chamber 87a exceeds the appropriate saturated negative pressure value Prf by 6.7 kPa or more, a stick abnormality occurs in the nozzle vane 74 of the turbocharger 35. You can see that
[0065]
In addition, when the time until the negative pressure in the negative pressure chamber 87a reaches the appropriate saturation negative pressure value Prf is earlier than the shortest saturation time αt, it is understood that the wear abnormality has occurred in the joint 103. .
[0066]
Further, if the time until the negative pressure value in the negative pressure chamber 87a reaches the appropriate saturated negative pressure value Prf is between the longest saturation time βt and the threshold time γt, the actuator 87 of the turbocharger 35 has It can be seen that there is a leakage abnormality in which the amount of negative pressure loss is not large.
[0067]
In addition, if the negative pressure in the negative pressure chamber 87a does not reach the appropriate saturation negative pressure value Prf even after the threshold time γt has passed, the actuator 87 of the turbocharger 53 has a breakage abnormality with a large negative pressure loss. You can see that it has occurred.
[0068]
Next, an abnormality determination processing procedure based on the above-described conditions will be described based on a flowchart shown in FIG. Note that an abnormality cause flag for storing determination results of various abnormality causes is set in the RAM 95. In the present embodiment, these abnormality cause flags include a stick abnormality flag XST, a wear abnormality flag XSC, a leakage abnormality flag XLE, and a tear abnormality flag XBR.
[0069]
In this abnormality determination process, first, in step S101, it is monitored whether or not an ignition switch (not shown) of the engine 11 (shown as “IG” in the flowchart) is turned off. If it is determined that the ignition switch is turned off, the process proceeds to the next step S102.
[0070]
In the subsequent step S102, the EVRV 90 is once closed as initialization of the variable capacity mechanism. Further, each abnormality flag XST, XSC, XLE, XBR is reset to “0”.
[0071]
In the next step S103, the CPU 94 sends a drive signal to the EVRV 90 via the external output circuit 99 to drive the EVRV 90, thereby applying a negative pressure from the vacuum tank 102 to the negative pressure chamber 87a to test drive the diaphragm 88. Let
[0072]
Subsequently, in step S104, the CPU 94 activates the timer counter 104 to measure a time CT (hereinafter referred to as “elapsed time”) after the negative pressure starts to be applied to the negative pressure chamber 87a. And a process transfers to step S200 which is a subroutine which performs the negative pressure determination process based on the appropriate saturation negative pressure value Prf.
[0073]
Here, a specific flow of the negative pressure determination process based on the appropriate saturated negative pressure value Prf will be described based on the flowchart of FIG.
First, in step S201, the negative pressure value (hereinafter referred to as “actual negative pressure value”) Pt in the negative pressure chamber 87a acquired by the actuator pressure sensor 101 is compared with the appropriate saturated negative pressure value Prf. . If the actual negative pressure value Pt is lower than the appropriate saturated negative pressure value Prf, the process proceeds to step S202.
[0074]
In step S202, the elapsed time CT indicated by the counter timer 104 is compared with the threshold time γt which is the set reference value. If the elapsed time CT is smaller than the threshold time γt, the process returns to step S201.
[0075]
That is, in the processing of Step S201 and Step S202, the actual negative pressure value until the threshold time γt unless the actual negative pressure value Pt in the negative pressure chamber 87a where the negative pressure is applied reaches the appropriate saturated negative pressure value Prf. Pt is continuously acquired and compared with the appropriate saturated negative pressure value Prf.
[0076]
If the actual negative pressure value Pt does not reach the appropriate saturated negative pressure value Prf by the threshold time γt, the process proceeds to step S203.
In step S203, the breaking abnormality flag XBR set in the RAM 95 is set to “1”. Then, the process ends the process in the subroutine and returns to the main routine.
[0077]
That is, in the processing of step S201, step S202, and step S203, the actual negative pressure value Pt in the negative pressure chamber 87a becomes the appropriate saturated negative pressure value Prf by the threshold time γt after the negative pressure starts to act on the negative pressure chamber 87a. Therefore, the CPU 94 determines that the breakage abnormality with a large negative pressure loss has occurred in the actuator 87 of the turbocharger 35.
[0078]
Further, in the processing of step S201 and step S202, when the actual negative pressure value Pt reaches the appropriate saturated negative pressure value Prf by the threshold time γt, the processing moves to step S204.
[0079]
In step S204, a comparison determination is made between the elapsed time CT when the actual negative pressure value Pt reaches the appropriate saturated negative pressure value Prf and the threshold time αt. If the elapsed time CT is earlier than the threshold time αt, the process proceeds to step S205.
[0080]
In step S205, it is compared and determined whether the actual negative pressure value Pt is 6.7 kPa or more greater than the appropriate saturated negative pressure value Prf. When the actual negative pressure value Pt is smaller than the value obtained by adding 6.7 kPa to the appropriate saturated negative pressure value Prf, the process proceeds to step S207.
[0081]
In step S207, it is determined whether or not the elapsed time CT has reached the threshold time αt. If the elapsed time CT has not reached the threshold time αt, the process returns to step S205.
[0082]
That is, in the processing of step S205 and step S207, the actual negative pressure value Pt in the negative pressure chamber 87a in which the negative pressure is applied until the threshold time αt is 6.7 kPa or more of the appropriate saturated negative pressure value Prf. A comparison judgment is performed.
[0083]
If the actual negative pressure value Pt exceeds the appropriate saturated negative pressure value Prf by 6.7 kPa or more by the threshold time αt, the process proceeds to step S206.
In step S206, the stick abnormality flag XST set in the RAM 95 is set to “1”. Then, the process ends the process in the subroutine and returns to the main routine.
[0084]
That is, in the processing of step S205, step S206, and step S207, since the appropriate saturated negative pressure value Prf exceeded 6.7 kPa or more earlier than the threshold time αt after the negative pressure began to act on the negative pressure chamber 87a, The CPU 94 determines that a stick abnormality has occurred in the nozzle vane 74.
[0085]
Further, in the processing of step S205 and step S207, if the actual negative pressure value Pt does not exceed the appropriate saturated negative pressure value Prf by 6.7 kPa or more before the elapsed time CT reaches the threshold time αt, the processing moves to step S208. To do.
[0086]
In step S208, the wear abnormality flag XSC set in the RAM 95 is set to “1”. Then, the process ends the process in the subroutine and returns to the main routine.
[0087]
That is, in the processing of step S205, step S207, and step S208, the actual negative pressure value Pt that has reached the appropriate saturated negative pressure value Prf earlier than the threshold time αt is changed to the appropriate saturated negative pressure value Prf by the threshold time αt. Therefore, the CPU 94 determines that a wear abnormality has occurred in the joint 103 of the turbocharger 35.
[0088]
In step S204, when the elapsed time CT when the actual negative pressure value Pt reaches the appropriate saturated negative pressure value Prf has passed the threshold time αt, the process proceeds to step S209.
[0089]
In step S209, it is compared and determined whether or not the elapsed time CT is greater than or equal to the threshold time αt and less than the threshold time βt. If the elapsed time CT is greater than or equal to the threshold time αt and less than the threshold time βt, the process ends the process in the subroutine and returns to the main routine without setting any abnormality cause flag.
[0090]
That is, in the processes of step S201, step S204, and step S209, since the actual negative pressure value Pt has reached the appropriate saturated negative pressure value Prf during the threshold time βt from the threshold time αt, the CPU 94 detects the turbocharger 35. Is determined to be operating normally.
[0091]
In step S209, if the elapsed time CT when the actual negative pressure value Pt reaches the appropriate saturated negative pressure value Prf is equal to or longer than the threshold time βt, the process proceeds to step S210.
[0092]
In step S210, it is determined whether or not the elapsed time CT is greater than or equal to the threshold time βt and less than the threshold time γt. If the elapsed time CT is greater than or equal to the threshold time βt and less than the threshold time γt, the process proceeds to step S211.
[0093]
In step S211, the leakage abnormality flag XLE set in the RAM 95 is set to “1”. Then, the process ends the process in the subroutine and returns to the main routine.
[0094]
That is, in the processing of step S209, step S210, and step S211, since the actual negative pressure value Pt has passed the threshold time βt but reached the appropriate saturation negative pressure Prf by the threshold time γt, the CPU 94 detects the turbocharger 35. It is determined that a leakage abnormality with a small negative pressure loss has occurred in the actuator 87.
[0095]
In step S210, when the elapsed time CT when the actual negative pressure value Pt reaches the appropriate saturated negative pressure value Prf has passed the threshold time γt, the process proceeds to step S203 and is the same as described above. The breakage abnormality flag XBR is set to “1”.
[0096]
That is, in the processing of step S210 and step S203, since the actual negative pressure value Pt has reached the appropriate saturated negative pressure Prf after the threshold time γt has passed, the CPU 94 has a negative pressure applied to the actuator 87 of the turbocharger 35. It is determined that a tearing abnormality with a large amount of missing has occurred.
[0097]
After performing the negative pressure determination based on the appropriate saturated negative pressure value Prf as described above, the processing returns to the main routine. At this time, if the occurrence of an abnormality in the turbocharger 35 is determined, one of the abnormality cause flags determined to be the cause of the abnormality that has occurred is set to “1”. Further, if it is determined that the turbocharger 35 is operating normally, the abnormality cause flags are all reset to “0”.
[0098]
In the process that has returned to the main routine (FIG. 7), the timer counter 104 is stopped in step S105, and the process proceeds to the next step S106.
In step S106, it is determined whether the stick abnormality flag XST is set to “1”. If the stick abnormality flag XST is set to “1”, the process proceeds to step S107.
[0099]
In step S107, the warning lamp 100a indicating the occurrence of the stick abnormality is turned on, and the main routine is terminated.
If the stick abnormality flag XST is “0” in step S106, the process proceeds to step S108.
[0100]
In step S108, it is determined whether the wear abnormality flag XSC is set to “1”. If the wear abnormality flag XSC is set to “1”, the process proceeds to step S109.
[0101]
In the process, the warning lamp 100b indicating the occurrence of abnormal wear is turned on in step S109, and the main routine is terminated.
If the wear abnormality flag XSC is “0” in step S108, the process proceeds to step S110.
[0102]
In step S110, it is determined whether or not the leakage abnormality flag XLE is set to “1”. If the leakage abnormality flag XLE is set to “1”, the process proceeds to step S111.
[0103]
In step S111, the warning lamp 100c indicating the occurrence of a leakage abnormality is turned on, and the main routine is terminated.
If the leakage abnormality flag XLE is “0” in step S110, the process proceeds to step S112.
[0104]
In step S112, it is determined whether the torn abnormality flag XBR is set to “1”. If the tear abnormality flag XBR is set to “1”, the process proceeds to step S113.
[0105]
In step S113, the alarm lamp 100d indicating the occurrence of a breakage abnormality is turned on, and the main routine is terminated.
If the break abnormality flag XLE is “0” in step S113, the CPU 94 ends the abnormality determination main routine without lighting any of the alarm lamps 100a to 100d, assuming that the variable capacity mechanism is operating normally.
[0106]
As described in detail above, according to the present embodiment, the following effects can be obtained.
Since the variable capacity mechanism (actuator 87) is test-driven with the ignition off, the presence or absence of abnormality is determined based on the negative pressure detection result in the negative pressure chamber 87a by the actuator pressure sensor 101 at that time. It is possible to easily and reliably determine the abnormality including the control system of the turbocharger 35 that is a variable capacity type.
[0107]
When an abnormality occurs in the turbocharger 35, the result of determining the cause is individually displayed, so that the cause can be easily known and the countermeasure can be quickly taken.
[0108]
Since the presence or absence of abnormality of the turbocharger 35 is determined from the transition of the negative pressure acting on the actuator 87, there is no need to operate the internal combustion engine. Therefore, even when there is an abnormality in the internal combustion engine, the internal combustion engine is not burdened.
[0109]
It should be noted that this embodiment can be implemented with the following modifications.
In the present embodiment, abnormality determination is performed with the ignition off, but as long as it has a vacuum tank in which negative pressure is accumulated by driving an appropriate actuator, the above is also possible when the ignition is turned on. The abnormality determination process can also be performed by accumulating negative pressure in the vacuum pump based on the driving of the actuator. In this way, an abnormality can be detected before the vehicle is driven. Further, the abnormality determination process may be performed both when the ignition is on and when the ignition is off.
[0110]
In the present embodiment, the abnormality determination process is executed only once for one abnormality determination. However, the abnormality determination is performed based on whether the same result is obtained a predetermined number of times by executing the abnormality determination process a plurality of times. A determination may be made. In this way, the determination accuracy can be improved.
[0111]
In the present embodiment, only when the ECU 92 determines that the result of the determination is an abnormality, the alarm lamps 100a to 100d corresponding to the cause of the abnormality are turned on to notify the driver of the occurrence of the abnormality and its contents. However, it is good also as only one warning lamp which shows only the presence or absence of abnormality occurrence. In this case, in particular, the above-described abnormality cause flags are recorded in the backup RAM 96 and read out at the time of repair at a dealer or the like, so that an effect similar to the above can be obtained and the operation can be performed. The configuration of the instrument panel of the seat can be simplified.
[0112]
A normal operation lamp may be provided to notify that the turbocharger 35 is normal when the ECU 92 determines that no abnormality has occurred in the turbocharger 35 based on the result of the abnormality determination process. In this way, even when the turbocharger 35 is operating normally, the result can be clearly notified to the driver. In addition, even when the abnormality determination device itself fails and is not operating, the failure can be noticed by not lighting any lamp.
[0113]
In the present embodiment, only when the ECU 92 determines that the result of the determination is the occurrence of abnormality, one of the plurality of alarm lamps 100a to 100d corresponding to the cause of the abnormality is turned on to generate an abnormality in the driver. However, the cause of various abnormalities may be notified by changing the lighting interval of one alarm lamp. Even in this case, the configuration of the instrument panel can be simplified.
In the present embodiment, the various alarm lamps 100a to 100d are turned on according to the cause of the abnormality, but may be notified by a buzzer having a different sound.
[0114]
In the present embodiment, the determination is performed using the reference value stored in the ROM 93 in advance. However, the determination is made appropriately every time abnormality is determined in the initial fixed period or the entire operation period of the internal combustion engine. The saturated negative pressure value and the time required to reach the negative pressure value are recorded in the backup RAM 96, and a new appropriate saturated negative pressure value Prf, a minimum saturation time αt, and a longest saturation time βt are learned by learning this. May be reset. In this way, it is possible to make a determination in consideration of the individual difference of each variable capacity mechanism, which will be slightly different for each vehicle, and it is possible to perform a more accurate abnormality determination.
[0115]
In the present embodiment, the amount of negative pressure loss is treated as two types of abnormalities, ie, a leakage abnormality and a tear abnormality, but the negative pressure loss amount may be further classified. In this way, when the abnormality occurs in the turbocharger 35, more detailed measures can be taken quickly.
[0116]
The abnormality determination device according to the present embodiment is applied to a variable displacement turbocharger of a diesel engine, but may be applied to a variable displacement turbocharger of a gasoline engine.
[0117]
In this embodiment, a vacuum pump is used as a negative pressure generation source, but intake negative pressure generated in the intake path may be used.
In this embodiment, when an abnormality is detected, an alarm lamp corresponding to the cause of the abnormality is turned on. However, when a stick abnormality occurs, the nozzle vane 74 is automatically operated with the maximum driving force. For example, various countermeasures corresponding to various causes of abnormalities such as returning from the stick state may be automatically executed.
[0118]
In the present embodiment, the transition of the negative pressure up to the threshold time αt is detected to determine whether or not a stick abnormality has occurred, but this is different from the process for determining whether or not this stick abnormality has occurred. It may be implemented routinely. In this way, it is possible to detect whether or not a stick abnormality has occurred even after the threshold time αt.
[0119]
【The invention's effect】
As described above in detail, according to the configuration of the first aspect of the present invention, the occurrence of abnormality in the variable capacity turbocharger is not the supercharging pressure of the turbocharger but the driving pressure of the actuator that operates the variable capacity mechanism. Is detected. Therefore, it is possible to easily determine whether there is an abnormality in the turbocharger without operating the internal combustion engine and generating supercharging pressure.
[0122]
  Claim6According to the configuration of the invention described above, since it is possible to determine whether or not an abnormality of the turbocharger occurs other than during the operation of the internal combustion engine, it is possible to prevent the abnormality from occurring during the operation of the internal combustion engine.
[0123]
  Claim 7Or 8According to the configuration of the invention described in (1), it is possible to determine whether or not an abnormality has occurred without affecting the characteristics of the operating internal combustion engine.
  Claim9According to the configuration of the invention described in (3), it is possible to accurately notify the driver of the abnormality occurring in the variable capacity turbocharger or the cause thereof by the warning means.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a diesel engine system to which an embodiment of the invention is applied.
FIG. 2 is a sectional view showing the structure of a variable capacity turbocharger of the engine.
FIG. 3 is a cross-sectional view and a plan view showing a variable nozzle mechanism of the turbocharger.
FIG. 4 is a schematic diagram showing a drive system of the variable nozzle mechanism.
FIG. 5 is a block diagram showing an electrical configuration of the engine system.
FIG. 6 is a graph showing the relationship between the transition of negative pressure in the negative pressure chamber and various abnormal contents.
FIG. 7 is a flowchart showing an abnormality determination procedure according to the present embodiment.
FIG. 8 is a flowchart showing an abnormality content determination procedure according to the present embodiment;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Diesel engine, 35 ... Turbocharger, 74 ... Nozzle vane, 87 ... Actuator, 87a ... Negative pressure chamber, 88 ... Diaphragm, 88b ... Rod, 88c ... Link, 90 ... EVRV, 91 ... Vacuum pump, 92 ... ECU, 100a -D ... Each alarm lamp, 101 ... Pressure sensor for actuator, 102 ... Vacuum tank, 103 ... Joint, 104 ... Timer counter.

Claims (9)

A variable in which the amount of operation is controlled through operation of a variable displacement mechanism by a pressure-driven actuator while supercharging air sucked into a combustion chamber of the engine by operating based on an exhaust gas flow from the internal combustion engine An abnormality determination device for a capacity-type turbocharger,
Pressure detecting means for detecting the driving pressure of the actuator;
An abnormality determining means for determining the contents of a plurality of abnormalities of the turbocharger based on the time until the driving pressure of the actuator detected by the pressure detecting means reaches an appropriate saturated negative pressure value to be saturated ,
The plurality of abnormalities are detected by an actuator that is detected more than a shortest saturation time that is a shortest time until the driving pressure of the detected actuator reaches the appropriate saturated negative pressure value in accordance with the normal operation of the turbocharger. Including abnormalities when the time until the drive pressure reaches the appropriate saturation negative pressure value is early
Variable capacity turbocharger abnormality determining device comprising a call. A variable in which the amount of operation is controlled through operation of a variable displacement mechanism by a pressure-driven actuator while supercharging air sucked into a combustion chamber of the engine by operating based on an exhaust gas flow from the internal combustion engine An abnormality determination device for a capacity-type turbocharger,
A joint connecting the actuator and the variable capacity mechanism ;
Pressure detecting means for detecting the driving pressure of the actuator;
An abnormality determining means for determining whether or not an abnormality has occurred in the turbocharger based on a time until the driving pressure of the actuator detected by the pressure detecting means reaches an appropriate saturated negative pressure value to be saturated,
The abnormality determination means is configured to detect the actuator detected more than a shortest saturation time which is a shortest time until the drive pressure of the detected actuator reaches the appropriate saturated negative pressure value with a normal operation of the turbocharger. in which the driving pressure is determined to abnormal wear to the joint when the not early time to reach the proper saturation negative pressure is generated
An abnormality determination device for a variable capacity turbocharger characterized by the above . A variable in which the amount of operation is controlled through operation of a variable displacement mechanism by a pressure-driven actuator while supercharging air sucked into a combustion chamber of the engine by operating based on an exhaust gas flow from the internal combustion engine An abnormality determination device for a capacity-type turbocharger,
The variable capacity mechanism has a turbine wheel and a nozzle vane that changes a flow rate of exhaust gas blown to the turbine wheel by opening and closing drive,
Pressure detecting means for detecting the driving pressure of the actuator;
An abnormality determining means for determining whether or not an abnormality has occurred in the turbocharger based on a time until the driving pressure of the actuator detected by the pressure detecting means reaches an appropriate saturated negative pressure value to be saturated,
The abnormality determination means is configured to detect the actuator detected more than a shortest saturation time which is a shortest time until the drive pressure of the detected actuator reaches the appropriate saturated negative pressure value with a normal operation of the turbocharger. When the time until the drive pressure reaches the appropriate saturated negative pressure value is early, the detected actuator drive pressure is compared with a reference pressure set in advance with respect to the drive pressure, and based on the comparison result The nozzle vane determines that a stick abnormality has occurred.
An abnormality determination device for a variable capacity turbocharger characterized by the above . The abnormality determination means determines that the time required for the detected actuator driving pressure to reach the appropriate saturation negative pressure value is determined so that the detected actuator driving pressure with the normal operation of the turbocharger is the appropriate saturation. When the actuator is between the longest saturation time, which is the longest time until the negative pressure value is reached, and a predetermined threshold time in a range larger than the longest saturation time, the actuator has a little negative pressure loss. The abnormality determination device for a variable capacity turbocharger according to any one of claims 1 to 3, wherein it is determined that a small number of leakage abnormality has occurred. Before SL abnormality determination unit than the longest saturation time from the longest saturation time is the longest time until the driving pressure of the actuators the detected along with the normal operation of the turbocharger reaches the proper saturation negative pressure When the detected actuator driving pressure does not reach the appropriate saturated negative pressure value even after a predetermined threshold time in a large range, the actuator has a breakage abnormality with a large negative pressure loss . The abnormality determination device for a variable capacity turbocharger according to any one of claims 1 to 4. The abnormality of the variable capacity turbocharger according to any one of claims 1 to 5, wherein the abnormality determination unit performs the determination by performing a test drive of the actuator at least one of when the internal combustion engine is stopped and started. Judgment device. The abnormality determination device for a variable displacement turbocharger according to claim 1, wherein the abnormality determination unit performs the determination by performing a test drive of the actuator during idling of an internal combustion engine. A variable in which the amount of operation is controlled through operation of a variable displacement mechanism by a pressure-driven actuator while supercharging air sucked into a combustion chamber of the engine by operating based on an exhaust gas flow from the internal combustion engine An abnormality determination device for a capacity-type turbocharger,
Pressure detecting means for detecting the driving pressure of the actuator;
An abnormality determining means for determining whether or not an abnormality has occurred in the turbocharger based on a time until the driving pressure of the actuator detected by the pressure detecting means reaches an appropriate saturated negative pressure value to be saturated,
The abnormality determination device for a variable capacity turbocharger , wherein the abnormality determination means performs the determination by performing a test drive of the actuator during idling of an internal combustion engine .   In the abnormality determination apparatus of the variable capacity turbocharger according to any one of claims 1 to 8,
  Alarm means for appropriately warning the abnormality determination result by the abnormality determination means is further provided.
  An abnormality determination device for a variable capacity turbocharger characterized by the above.

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