JP4024985B2 - Fuel pump control device for marine internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel pump control device for a marine internal combustion engine.
[0002]
[Prior art]
In a marine internal combustion engine, generally, one fuel pump is disposed in a fuel supply system, and is driven through an electric motor to pump fuel from a fuel tank and pump it. The fuel pump is also used with a discharge capacity that can handle the maximum load required by the internal combustion engine, and is operated at the maximum output even at low load.
[0003]
[Problems to be solved by the invention]
In this way, even when the discharge amount required by the engine at a low load is relatively small, the fuel pump is operated at the maximum output, so it is difficult to ignore the consumed fuel and the energization amount increases. There was room for improvement in terms of energy saving. In addition, driving at the maximum output at low load tends to cause an increase in fuel temperature during idling, and evaporative fuel is generated, leaving room for improvement in both fuel efficiency and emission performance.
[0004]
Accordingly, an object of the present invention is to provide a fuel pump control device for a marine internal combustion engine that solves the above-described problems, realizes energy saving, and improves fuel efficiency and emission performance.
[0005]
[Means for Solving the Problems]
In order to solve the above-described object, the present invention provides a fuel pump control device arranged in a fuel supply system for supplying fuel from a fuel tank to an internal combustion engine mounted on a ship. At least one auxiliary fuel pump arranged in parallel with the fuel pump in the system, operating state detecting means for detecting an operating state including at least the rotational speed and load of the internal combustion engine, and the detected load being detected A load state determining means for determining whether or not the internal combustion engine is in a high load state by comparing with a predetermined value set according to the rotational speed; and when it is determined that the internal combustion engine is in a high load state, the fuel When all of the pump and the auxiliary fuel pump are driven and when it is determined that the internal combustion engine is not in a high load state, at least one of the fuel pump and the auxiliary fuel pump is driven. When the pump drive means, and the fuel pump and the secondary fuel pump all driven to start the internal combustion engine, with the fuel pump and the secondary fuel pump is determined whether all is normal, the fuel pump and the secondary fuel when the pump is not determined that all normal, and as constituted comprising an abnormality detection means for detecting at least one is abnormal in the fuel pump and the secondary fuel pump.
[0006]
The fuel supply system includes at least one sub fuel pump arranged in parallel with the fuel pump, and when the internal combustion engine is determined to be in a high load state, the fuel pump and the sub fuel pump are driven and the high load state When it is determined that the fuel pump is not present, at least one of the fuel pump and the auxiliary fuel pump is driven, so that the amount of power supplied to the electric motor of the fuel pump can be stopped to the minimum necessary, and the fuel consumption As well as energy saving.
[0007]
In addition, by driving only at least one in a low load state, it is possible to suppress an increase in fuel temperature during idling, to suppress the generation of evaporated fuel, and to improve fuel efficiency and emission performance. be able to. Furthermore, it can be easily applied to a fuel pump control device of an existing marine internal combustion engine.
[0008]
Further, the valve timing and the lift amount of the internal combustion engine may be set between the high output side characteristic and the low output side characteristic based on at least the detected engine speed in the operating state. in the variable valve timing mechanism that selectively switches, wherein the load state determining means, said internal combustion engine to determine the properties that are selected in the previous SL variable valve timing mechanism is judged whether or not the high-load state It was configured as follows.
[0009]
Since the internal combustion engine to determine the properties that are selected in the variable valve timing mechanism is composed as determined whether the high load state, it is possible to accurately determine high load, thus more effectively Energy saving can be realized, and fuel efficiency and emission performance can be improved.
[0010]
According to a third aspect of the present invention, the pump driving means is configured to switch between the fuel pump and the auxiliary fuel pump when driving at least one of the fuel pumps under a predetermined condition.
[0011]
When at least one fuel pump is driven, switching between the fuel pump and the auxiliary fuel pump is performed under a predetermined condition. More specifically, when the detected engine speed is lower than the predetermined speed, the engine is started. Since the fuel pump to be driven is changed every time, the use time per fuel pump can be shortened, and continuous use can be avoided, thereby improving the durability of the fuel pump. Can be improved.
[0013]
Further, when the effect of claim 1 is applied, when all of the fuel pump and the auxiliary fuel pump are driven and the engine is started, it is determined whether or not all of the fuel pump and the auxiliary fuel pump are normal, and when the fuel pump is not determined that all normal, since at least one among the fuel pump and the secondary fuel pump is composed as provided with abnormality detecting means for detecting that there is an abnormality, the fuel etc. before departure in the grade which is not cumbersome Pump abnormalities can be checked regularly.
[0014]
According to a fourth aspect of the present invention, the abnormality detection means is configured to detect an abnormality by detecting an energization current supplied to the drive motors of the fuel pump and the auxiliary fuel pump.
[0015]
Since an abnormality is detected by detecting the energization current supplied to the drive motors of the fuel pump and the auxiliary fuel pump, the abnormality can be detected with high accuracy in addition to the effects described above.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a fuel pump control device for a marine internal combustion engine according to an embodiment of the present invention will be described with reference to the accompanying drawings.
[0017]
FIG. 1 is a schematic view generally showing the fuel pump control device of the marine internal combustion engine, and FIG. 2 is a partial side view of FIG.
[0018]
1 and 2, reference numeral 10 indicates a propulsion engine (hereinafter referred to as “outboard motor”) in which the aforementioned engine, propeller shaft, propeller, and the like are integrated. The outboard motor 10 is mounted on the stern of a ship (small ship) 12 shown in FIG. 1 via a clamp unit 14 (shown in FIG. 2).
[0019]
As shown in FIG. 2, the outboard motor 10 includes an internal combustion engine (hereinafter referred to as “engine”) 16. The engine 16 is a spark ignition type V-type 6-cylinder gasoline engine. The engine 16 is located on the water surface, covered with the engine cover 20, and disposed inside the outboard motor 10. In the vicinity of the engine 16 covered with the engine cover 20, an electronic control unit (hereinafter referred to as "ECU") 22 comprising a microcomputer is arranged.
[0020]
As shown in FIG. 1, a steering wheel 24 is disposed near the cockpit of the ship 12. The rotation of the steering wheel 24 input by the operator is transmitted to a ladder (not shown) attached to the stern via a steering mechanism (not shown) to determine the traveling direction.
[0021]
A throttle lever 26 is disposed on the right side of the cockpit, and a throttle lever position sensor 30 is disposed in the vicinity thereof to output a signal corresponding to the position of the throttle lever 26 operated by the driver.
[0022]
Further, a shift lever 32 is disposed adjacent to the throttle lever 26, and a neutral switch 34 is disposed in the vicinity thereof. When the shift lever 32 operated (shifted) by the driver is in the neutral position, an ON signal is given. When in the forward (or reverse) position, an off signal is output.
[0023]
The outputs of the throttle lever position sensor 30 and the neutral switch 34 described above are sent to the ECU 22 via signal lines 30a and 34a.
[0024]
The output of the engine 16 is connected to a clutch 36 disposed at a position below the surface of the outboard motor 10 via a crankshaft and a drive shaft (both not shown). The clutch 36 is connected to the propeller 40 via a propeller shaft (not shown).
[0025]
The clutch 36 is formed of a known gear mechanism, and although not shown, when the engine 16 rotates, a drive gear that rotates integrally with the drive shaft, and meshes with the drive gear and idles in opposite directions on the propeller shaft. A forward gear and a reverse gear, and a dog (slide clutch) that rotates integrally with the propeller shaft are provided.
[0026]
The ECU 22 drives the actuator (electric motor) 42 so as to realize the intended shift position through a drive circuit (not shown) according to the output of the neutral switch 34 sent through the signal line 34a. The drive of the actuator 42 is transmitted to the dog via the shift rod 44.
[0027]
When the shift lever 32 is operated to the neutral position, the rotation of the engine 16 and the propeller shaft is stopped. When the shift lever 32 is operated (shifted) to the forward or reverse position, the dog is engaged with the forward gear or the reverse gear. The rotation of the engine 16 is transmitted to the propeller 40 via the propeller shaft, and the propeller 40 is rotated in the forward direction or the reverse direction opposite thereto to advance or reverse the ship 12.
[0028]
Next, the engine 16 will be described with reference to FIGS. 3 and 4.
[0029]
As shown in FIG. 3, the engine 16 includes an intake pipe 46, and the air sucked through an air cleaner (not shown) has a V shape when viewed from the front while the flow rate is adjusted through a throttle valve 50. It flows through an intake manifold 52 provided for each of the left and right banks, and reaches an intake valve (not shown). In the vicinity of the intake valve, an injector 54 (not shown in FIG. 3) is arranged to inject gasoline fuel.
[0030]
The injector 54 is connected to a fuel tank (not shown) for storing gasoline fuel via two fuel supply pipes 56 provided for each of the left and right banks. Fuel pumps (fuel pumps) 58a and 58b are respectively inserted in the middle of the two fuel supply pipes 56, and are driven by an electric motor (not shown) via a relay circuit 60 to pump gasoline fuel to the injector. .
[0031]
The fuel pumps 58a and 58b can correspond to the maximum load required by the engine 16 by the sum of their discharge capacities. In other words, if both the fuel pumps 58a and 58b are driven (operated) at a high load. The one having specifications (rated) that can satisfy the maximum load required by the engine 16 is used. In the following description, the fuel pumps (fuel pumps) 58a and 58b are also referred to as “FFP”, “FLRM”, “FLRS”, or the like. Reference numeral 62 represents an evaporative fuel separator.
[0032]
The inflow air mixes with the injected gasoline fuel to form an air-fuel mixture, flows into each cylinder combustion chamber (not shown), is ignited and burned by a spark plug 64 (not shown in FIG. 3), and the piston ( (Not shown) is driven downward. Thus, the generated engine output is taken out through the crankshaft.
[0033]
On the other hand, the exhaust gas after combustion flows through the exhaust valve 66 through the exhaust manifold 70 for each of the left and right banks, and is discharged outside the engine.
[0034]
As shown in the figure, the intake pipe 46 branches off upstream of the position where the throttle valve 50 is disposed, and a secondary air supply branch path (passage) 72 is connected to the intake pipe 46 again downstream of the throttle valve 50. Form. The branch path 72 includes a secondary air control valve (hereinafter referred to as “EACV”) 74. The EACV 74 is connected to an actuator (electromagnetic solenoid) 76.
[0035]
The actuator 76 is connected to the ECU 22 described above. As will be described later, the ECU 22 calculates an energization command value and supplies it to the actuator 76, drives the EACV 74, and adjusts the opening degree of the branch path 72. As described above, the secondary air supply device 80 that includes the branch path (passage) 72 and the EACV 74 (and the actuator 76) and supplies secondary air corresponding to the opening degree of the secondary air control valve is provided.
[0036]
Further, the throttle valve 50 is connected to an actuator (pulse motor) 82. The actuator 82 is connected to the ECU 22. The ECU 22 calculates an energization command value according to the output of the throttle lever position sensor 30 and supplies it to the actuator 82 via a drive circuit (not shown) to adjust the throttle opening TH.
[0037]
More specifically, the actuator 82 is directly attached to the throttle body 50a that houses the throttle valve 50 so that the rotation shaft (not shown) is coaxial with the throttle valve shaft. In other words, the actuator 82 is configured to be directly attached to the throttle body 50a without using a link mechanism or the like, thereby simplifying the mechanism and omitting the installation space.
[0038]
As described above, in this embodiment, the push-pull cable is removed, and the actuator 82 is directly attached to the throttle body 50a to drive the throttle valve 50.
[0039]
In the engine 16, a variable valve timing mechanism 84 is provided in the vicinity of the intake valve and the exhaust valve 66. The variable valve timing mechanism 84 switches the valve timing and lift amount to a relatively large value (high output characteristics or HiV / T) when the engine speed and load are relatively high, and when the engine speed and load are relatively low. The valve timing and the lift amount are selectively switched between relatively small values (low output characteristics or LoV / T).
[0040]
Further, the exhaust system and the intake system of the engine 16 are connected by an EGR passage 86, and an EGR control valve 90 is inserted in the middle thereof to recirculate a part of the exhaust gas to the intake system in a predetermined operation state. .
[0041]
A throttle opening sensor 92 is connected to the actuator 82 and outputs a signal proportional to the throttle opening TH according to the rotation of the throttle valve shaft. An absolute pressure sensor 94 is disposed downstream of the throttle valve 50, and outputs a signal corresponding to the intake pipe absolute pressure PBA (engine load). An atmospheric pressure sensor 96 is disposed near the engine 16 and outputs a signal corresponding to the atmospheric pressure PA.
[0042]
Further, an intake air temperature sensor 100 is disposed downstream of the throttle valve 50 and outputs a signal proportional to the intake air temperature TA. In addition, three overheat sensors 102 are arranged in the exhaust manifolds 70 in the left and right banks, and a signal proportional to the engine temperature is output, and a water temperature sensor 106 is arranged at an appropriate position of the cylinder block 104 in the vicinity thereof. A signal proportional to the coolant temperature TW is output.
[0043]
Further, an O ₂ sensor 110 is disposed in the exhaust manifold 70, and outputs a signal corresponding to the oxygen concentration in the exhaust gas. A knock sensor 112 is disposed at an appropriate position of the cylinder block 104 and outputs a signal corresponding to the knock.
[0044]
The description of the input and output of the sensor and ECU 22 will be continued with reference to FIG. In FIG. 3, the sensor and its signal lines are partially omitted.
[0045]
Detection resistors 116a and 116b are inserted in the middle of the motor energization circuits of the two fuel pumps 58a and 58b connected to the on-board battery 114, and both-end voltages are input to the ECU 22 via signal lines 118a and 118b. . The ECU 22 detects a voltage drop, detects an energization current, and determines whether the fuel pumps 58a and 58b are abnormal.
[0046]
Further, TDC sensors 120 and 122 and a crank angle sensor 124 are arranged in the vicinity of the crankshaft, and output a cylinder discrimination signal, an angle signal near each piston top dead center, and a crank angle signal every 30 degrees and send them to the ECU 22. To do. The ECU 22 calculates the engine speed NE from the crank angle sensor output.
[0047]
Further, a lift sensor 130 is disposed in the vicinity of the EGR control valve 90, and a signal corresponding to the lift amount (valve opening) of the EGR control valve 90 is output and sent to the ECU 22.
[0048]
Further, the output of the F terminal (ACGF) 134 of the AC generator (not shown) is inputted to the ECU 22, and three hydraulic switches 136 are arranged in the hydraulic circuit (not shown) of the variable valve timing mechanism 84. Then, a signal corresponding to the detected oil pressure is output and sent to the ECU 22. Further, a hydraulic switch 140 is disposed in a hydraulic circuit (not shown) of the engine 16 to output a signal corresponding to the detected hydraulic pressure and send it to the ECU 22.
[0049]
The ECU 22 is composed of a microcomputer as described above, and includes a backup EEPROM 22a. The ECU 22 performs an operation described later in accordance with the above-described input, and when the PGM (ECU) abnormality, overheating, hydraulic pressure abnormality, and ACG generator abnormality occur, the PCG lamp 146, the overheating lamp 148, the hydraulic lamp 150, and the ACG lamp 152 are turned on. Lights up and sounds a buzzer 154 to warn.
[0050]
In FIG. 4, the description of the remaining parts not directly related to the gist of the present invention is omitted.
[0051]
Next, the operation of the illustrated fuel pump control device for the marine internal combustion engine will be described.
[0052]
FIG. 5 is a main flow chart showing the operation. The illustrated program is looped every 40 msec, for example. In the following description, the fuel pumps (fuel pumps) 58a and 58b are collectively referred to as “FFP”, and one (for example, 58a) is referred to as “FLRM” and the other (for example, 58b) is referred to as “FLRS”.
[0053]
In the following, it is determined in S10 whether or not the value of the timer TMFP (down counter) has reached zero. When the ignition switch (not shown) of the engine 16 is turned on, this timer is set to a predetermined value and starts down-counting. Therefore, this determination is made after a predetermined time has elapsed since the ignition switch was turned on. This is equivalent to determining whether or not it has been done.
[0054]
In the first program loop, the determination in S10 is generally denied and the process proceeds to S12, in which it is determined whether or not the FFP has failed, that is, whether or not at least one of the fuel pumps 58a and 58b has failed.
[0055]
When the result in S12 is negative, it is determined that the engine has started, and the process proceeds to S14. It is determined whether the AST bit is set to 1. This flag is set to 1 when the engine 16 enters a state after starting in a routine not shown. In addition, when the engine 16 is in the state after starting, it means a state in which the detected engine speed NE has reached the complete explosion speed (500 rpm).
[0056]
In the first program loop, the determination in S14 is generally denied and the process proceeds to S16, where both FLRS and FLRM are turned on (driven) (that is, an electric motor (not shown) is energized for operation). Next, in S18, an FFP abnormality detection process is performed. The reason why both FLRS and FLRM are turned on (driven) in S16 is because of this abnormality detection processing.
[0057]
FIG. 6 is a subroutine flow chart showing the processing.
[0058]
Explaining below, in S100, the current flowing to the electric motors of FLRS and FLRM is detected. This is performed by detecting the voltage value and the ground value input via the signal lines 118a and 118b, that is, the voltage drop of the detection resistors 116a and 116b, and converting it into a current value.
[0059]
It is assumed that the detected current value for the electric motor of the FLRS (fuel pump 58a) is Ifs and the detected current value for the electric motor of the FLRM (fuel pump 58b) is Ifm. In addition, when naming both collectively, it is called If.
[0060]
Next, in S102, it is determined whether the detected current value If exceeds the predetermined value Iref1, or more specifically, whether the detected current value Ifs or Ifm exceeds the predetermined value Iref1 (is short-circuited).
[0061]
When the result in S102 is negative, the program proceeds to S104, and whether the detected current value If is lower than the predetermined value Iref2, or more specifically, whether the detected current value Ifs or Ifm is lower than the predetermined value Iref2 (disconnected). If not, both are determined to be normal, and the process proceeds to S106, where it is determined that the FFP (fuel pumps 58a, 58b) is normal.
[0062]
On the other hand, when the determination in S102 or S104 is affirmative, it is determined that at least one of FLRS and FLRM is abnormal, and the process proceeds to S108, whether the abnormality is FLRS, in other words, whether FLRS or FLRM is abnormal. When it is determined and affirmed, that is, when it is determined that an abnormality has occurred in FLRS, the process proceeds to S110, where FLRS is turned off (energization stopped) and FLRM is turned on. Next, in S112, it is determined that the FFP is abnormal (more specifically, FLRS abnormality).
[0063]
On the other hand, when the result in S108 is negative, that is, when it is determined that an abnormality has occurred in FLRM, the process proceeds to S114, FLRS is turned on, FLRM is turned off, the process proceeds to S112, and an FFP abnormality (more details) FLRM abnormality).
[0064]
In this way, it is possible to check before starting the port by energizing the two fuel pumps together at the time of start-up, and at the same time, it is possible to simplify the configuration by stopping the abnormality detection to the minimum necessary level. it can.
[0065]
Returning to the explanation of the flow chart of FIG. 5, when the result in S14 is affirmative and it is determined that the engine has been started, the process proceeds to S20, and a table search is performed for FPCTV. This value is a threshold value for determining the number of fuel pumps to be driven. FIG. 7 is an explanatory graph showing the characteristics. As shown in the figure, the characteristic is set to be searchable from the engine speed NE and the intake pipe absolute pressure PBA (engine load).
[0066]
Next, in S22, it is determined whether the detected intake pipe absolute pressure PBA is equal to or higher than the searched threshold value FPCTV. If the determination is affirmative, it is determined that the engine 16 is in a high load state, and the process proceeds to S24, where FLRS and FLRM Turn on together. As described above, the fuel pumps 58a and 58b are of the specifications that satisfy the maximum load of the engine 16 when the two discharge capacities are added up. Turn on both pumps together.
[0067]
On the other hand, when the result in S22 is negative, it is determined that only one fuel pump needs to be driven in the low load state, and the process proceeds to S26 to perform the FFP switching process.
[0068]
FIG. 8 is a subroutine flow chart showing the processing.
[0069]
In the following, in S200, the number of starts is counted, that is, the value is incremented using a start number counter. This increment is performed only once every time the engine 16 is started. That is, when the engine 16 is started using an appropriate flag, it is incremented only once and is not incremented until the engine 16 is stopped. The counter value is stored in the backup EEPROM 22a.
[0070]
Next, the routine proceeds to S202, where it is determined whether or not the detected engine rotational speed NE is equal to or lower than a predetermined rotational speed NEL (eg, 3000 rpm). If the result is affirmative and the engine 16 is determined to be at a relatively low rotational speed, the routine proceeds to S204. If the value of is not an odd value, the process proceeds to S206 when the result is affirmative and FLRS is selected. If the result is negative, the process proceeds to S208 and FLRM is selected.
[0071]
Note that FLRM may be selected in S206 and FLRS may be selected in S208. That is, when only one fuel pump is to be driven, it is only necessary to switch the fuel pump to be driven each time the engine 16 is started. Furthermore, the switching time is not limited to engine start, and switching may be performed by measuring usage time. In short, when only one fuel pump is to be driven, it is only necessary to switch the fuel pump to be driven under appropriate conditions.
[0072]
If the result of S202 is negative and it is determined that the engine speed is relatively high, the subsequent processing is skipped. This is because when the engine speed is relatively high, the load is high, and therefore both fuel pumps are driven.
[0073]
Returning to the description of the flow chart of FIG. 5, the process proceeds to S28, in which one of the fuel pumps, for example, FLRS is turned off and FLRM is turned on. At this time, if selected in the flowchart of FIG. 8, it goes without saying that the selected fuel pump is turned on.
[0074]
If the determination in S10 is affirmative, the process proceeds to S30, and it is determined whether or not a starter (not shown) is turned on. If the determination is affirmative, the process proceeds to S12. It is determined whether or not is a stall. When the result in S32 is negative, the process proceeds to S12. When the result is positive, the process proceeds to S34. Since the engine 16 is stalled, both FLRS and FLRM are turned off.
[0075]
If the result in S12 is affirmative, the subsequent processing is skipped.
[0076]
In this embodiment, as described above, two fuel pumps (FFP) 58a and 58b are provided, and a pump having a specification such that the sum of discharge capacities of the two fuel pumps satisfies the maximum load of the engine 16. The two fuel pumps are both driven (ON) in a high load state, and only one fuel pump is driven (ON) in a low load state.
[0077]
As a result, the energization amount to the electric motor of the fuel pump can be stopped to the minimum necessary, the fuel consumption can be reduced, and energy saving can be realized. In addition, by driving only one fuel pump at low load, it is possible to suppress an increase in fuel temperature during idling, to suppress generation of evaporated fuel, and to improve fuel efficiency and emission performance. Can do. Furthermore, it can be easily applied to existing devices.
[0078]
Furthermore, when only one fuel pump is driven (turned on), the pump used is changed every time the engine is started, so that the usage time per fuel pump can be shortened and continuous use is avoided. Therefore, the durability of the fuel pump can be improved.
[0079]
FIG. 9 is a flowchart similar to FIG. 5 showing the operation of the fuel pump control device for the marine internal combustion engine according to the second embodiment of the present invention.
[0080]
Description will be made focusing on the differences from the first embodiment. After performing the same processing from S300 to S308, the process proceeds to S310, and the flag F.F. It is determined whether or not the VTEC bit is set to 1.
[0081]
This flag is switched to a high output side characteristic (HiV / T) when the engine speed NE exceeds a predetermined speed Hi as shown in FIG. 10 in the control routine of another variable valve timing mechanism 84 (not shown). That bit is reset to zero.
[0082]
Therefore, the determination of this step corresponds to determining whether the engine 16 is in a high load state by determining the characteristic selected by the variable valve timing mechanism 84 in other words.
[0083]
When the result in S310 is affirmative, it is determined that the engine 16 is in a high load state, and the process proceeds to S312. Both FLRS and FLRM are turned on. When the result is negative, the process proceeds to S316 via S314 and only FLRM (or FLRS) Turn on.
[0084]
The remaining steps including the FFP switching process are not different from the first embodiment.
[0085]
Since the second embodiment is configured as described above, the same operations and effects as the first embodiment can be obtained.
[0086]
As described above, in this embodiment, the fuel pump (FFP) disposed in the fuel supply system (fuel supply pipe 56) that supplies fuel from the fuel tank to the internal combustion engine (engine 16) mounted on the ship 12. , FLRM) 58a (or 58b), at least one auxiliary fuel pump (FFP, FLRS) 58b (or 58a) disposed in parallel with the fuel pump in the fuel supply system, at least of the internal combustion engine Operating state detecting means (crank angle sensor 124, absolute pressure sensor 94, ECU 22) for detecting an operating state including a rotational speed (engine rotational speed NE) and a load (absolute pressure in the intake pipe PBA), and detecting the detected load A load condition for determining whether or not the internal combustion engine is in a high load state by comparing with a predetermined value (FPCTV) set in accordance with the set rotational speed When the determination means (ECU22, S20, S22, S310) determines that the internal combustion engine is in a high load state, the fuel pump and the auxiliary fuel pump are all driven (ECU, S24, S312), and the internal combustion engine Is determined not to be in a high load state, pump driving means (ECU, S28, S316) for driving at least one of the fuel pump and the auxiliary fuel pump, and all of the fuel pump and the auxiliary fuel pump are driven When the internal combustion engine is started, it is determined whether or not all of the fuel pump and the auxiliary fuel pump are normal, and when all of the fuel pump and the auxiliary fuel pump are not determined to be normal, the fuel pump and the auxiliary fuel pump are determined. abnormality detection means for detecting at least one is abnormal in the fuel pump (ECU22, S14, S16, S 8, S304, S306, S308, S100 from S114) was composed as comprising a.
[0087]
Further, the valve timing and the lift amount of the internal combustion engine are selectively selected between the high output side characteristic and the low output side characteristic based on at least the engine speed (engine speed NE) in the detected operating state. a variable valve timing mechanism (84) for switching on, the load state judgment means, or to determine the properties that are selected in the previous SL variable valve timing mechanism (ECU 22, S310) the internal combustion engine is in a high load state It was configured to determine whether or not.
[0088]
The pump driving means switches between the fuel pump and the auxiliary fuel pump when the fuel pump is driven under a predetermined condition when driving at least one of the fuel pumps (ECU 22, S26, S314, S200 to S208). Configured.
[0090]
The abnormality detection means is configured to detect an abnormality by detecting an energization current supplied to the drive motors of the fuel pump and the auxiliary fuel pump (ECU 22, S18, S100, S102, S104, S108).
[0091]
Although the fuel pump switching process is inserted in the processes of FIGS. 5 and 9, this is not essential, and the number of fuel pumps to be driven may be determined and controlled according to the engine load state. .
[0092]
In addition, although it is configured to include a total of two fuel pumps, in other words, one auxiliary fuel pump, the number of fuel pumps that are provided with a total of three or more fuel pumps and should be driven according to the load condition of the engine. May be changed.
[0093]
Furthermore, although the embodiment of the present invention has been described by taking an outboard motor as an example, the present invention is not limited to this, and the present invention is also applicable to an inboard engine.
[0094]
【The invention's effect】
According to claim 1, the fuel supply system includes at least one sub fuel pump arranged in parallel with the fuel pump, and when it is determined that the internal combustion engine is in a high load state, the fuel pump and the sub fuel Since it is configured to drive at least one of the fuel pump and the auxiliary fuel pump when it is determined that the pump is not in a high load state while driving the pump, the amount of power supplied to the electric motor of the fuel pump is also the minimum necessary It can be stopped to the limit, fuel consumption can be saved, and energy saving can be realized.
[0095]
In addition, by driving only at least one in a low load state, it is possible to suppress an increase in fuel temperature during idling, to suppress the generation of evaporated fuel, and to improve fuel efficiency and emission performance. be able to. Furthermore, it can be easily applied to a fuel pump control device of an existing marine internal combustion engine.
[0096]
In the second aspect paragraphs Owing to this configuration determines whether the internal combustion engine to determine the properties that are selected in the variable valve timing mechanism is in a high load condition, accurately determine the high-load state Therefore, energy saving can be realized more effectively, and fuel efficiency and emission performance can be improved.
[0097]
According to the third aspect of the present invention, when driving at least one fuel pump, switching between the fuel pump and the auxiliary fuel pump is performed under a predetermined condition. More specifically, the detected engine speed is predetermined. Since the fuel pump to be driven is changed every time the engine is started when the engine speed is below the number of revolutions, the usage time per fuel pump can be shortened and continuous use can be avoided. Therefore, the durability of the fuel pump can be improved.
[0098]
Further, when the effect of claim 1 is applied, when starting the engine by driving all of the fuel pump and the auxiliary fuel pump, it is determined whether or not all of the fuel pump and the auxiliary fuel pump are normal, When all the sub fuel pumps are not judged to be normal, it is configured to include an abnormality detection means for detecting that at least one of the fuel pump and the sub fuel pump is abnormal , so that it does not bother before leaving the port. It is possible to periodically check for abnormalities in the fuel pump.
[0099]
According to the fourth aspect of the present invention, since the abnormality is detected by detecting the energization current supplied to the drive motors of the fuel pump and the auxiliary fuel pump, the abnormality can be accurately detected in addition to the above-described effects. Can do.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram generally showing a fuel pump control device for a marine internal combustion engine according to an embodiment of the present invention.
2 is a partial explanatory side view of FIG. 1; FIG.
FIG. 3 is a schematic diagram showing in detail the engine shown in FIG. 1;
4 is a block diagram showing in detail input / output of an electronic control unit (ECU) shown in FIG. 1; FIG.
FIG. 5 is a main flow chart showing the operation of the fuel pump control apparatus for the marine internal combustion engine shown in FIG. 1;
6 is a subroutine flow chart showing a fuel pump (FFP) abnormality detection process of the flow chart of FIG.
FIG. 7 is an explanatory graph showing table characteristics of threshold values used in the flowchart of FIG. 5;
8 is a subroutine flow chart showing a fuel pump (FFP) switching process of the flow chart of FIG.
FIG. 9 is a flow chart similar to FIG. 5, showing the operation of the fuel pump control device for the marine internal combustion engine according to the second embodiment of the present invention.
10 is an explanatory time chart showing characteristic switching according to the engine speed of the variable valve timing mechanism of the flow chart of FIG. 9;
[Explanation of symbols]
10 Propulsion engine (outboard motor)
12 Ship 16 Internal combustion engine
22 Electronic control unit (ECU)
26 Throttle lever 32 Shift lever 36 Clutch 40 Propeller 50 Throttle valve 56 Fuel supply pipe (fuel supply system)
58a, 58b Fuel pump 74 Secondary air control valve (EACV)
84 Variable valve timing mechanism 94 Absolute pressure sensor 116a, 116b Detection resistance 124 Crank angle sensor

Claims (4)

In a fuel pump control device arranged in a fuel supply system for supplying fuel from a fuel tank to an internal combustion engine mounted on a ship,
a. At least one auxiliary fuel pump disposed in parallel with the fuel pump in the fuel supply system;
b. An operating state detecting means for detecting an operating state including at least the rotational speed and load of the internal combustion engine;
c. A load state determining means for comparing the detected load with a predetermined value set in accordance with the detected rotational speed and determining whether or not the internal combustion engine is in a high load state;
d. When it is determined that the internal combustion engine is in a high load state, the fuel pump and the auxiliary fuel pump are all driven, and when it is determined that the internal combustion engine is not in a high load state, the fuel pump and the auxiliary fuel pump Pump drive means for driving at least one of
And e. When all the fuel pump and sub fuel pump are driven to start the internal combustion engine, it is determined whether or not all of the fuel pump and sub fuel pump are normal, and all of the fuel pump and sub fuel pump are normal. abnormality detection means for detecting a when it is not determined, at least one among the fuel pump and the secondary fuel pump is abnormal,
A fuel pump control device for an internal combustion engine for ships. further,
f. A variable valve timing mechanism that selectively switches the valve timing and lift amount of the internal combustion engine between a high output side characteristic and a low output side characteristic based on at least the engine speed in the detected operating state;
The load state determination means determines whether the internal combustion engine is in a high load state by determining a characteristic selected by the variable valve timing mechanism. Fuel pump control device for marine internal combustion engine.   The said pump drive means switches between the said fuel pump and a sub fuel pump, when it is under predetermined conditions, when driving the said fuel pump at least one, The claim 1 or 2 characterized by the above-mentioned. A fuel pump control device for a marine internal combustion engine.   2. The fuel pump control device for an internal combustion engine for a ship according to claim 1, wherein the abnormality detecting means detects an abnormality by detecting an energization current supplied to drive motors of the fuel pump and the auxiliary fuel pump. .

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