Control device for internal combustion engine

Abstract

To provide a control device for an internal combustion engine capable of promptly stopping the internal combustion engine after performing an operation to stop the internal combustion engine in a situation where it is desirable to stop the internal combustion engine.SOLUTION: A control device is a control device for an internal combustion engine mounted on a vehicle. The internal combustion engine includes a fuel tank, a fuel injection valve, a fuel passage, a shutoff valve disposed in the fuel passage, and a pressure sensor for detecting passage fuel pressure that is fuel pressure at a portion between the shutoff valve and the fuel injection valve in the fuel passage. The control device outputs a valve closing signal to the shutoff valve and executes determination processing for determining opening fixation of the shutoff valve on the basis of a reduction amount of the passage fuel pressure when a stop operation of the internal combustion engine is executed. When at least one of a condition where vehicle speed is higher than first determination speed (S410) and a condition where engine speed is second determination speed or higher (S440) is satisfied, the control device does not execute the determination processing.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a control device for an internal combustion engine. [Background technology]

[0002] Patent Document 1 discloses an internal combustion engine that uses gaseous fuel. A shutoff valve is arranged in a fuel passage of the internal combustion engine. When the internal combustion engine is stopped, the shutoff valve closes, thereby stopping the supply of fuel from the fuel tank to the fuel injection valve. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-041106 Summary of the Invention [Problem to be solved by the invention]

[0004] One method for determining whether a shutoff valve is stuck open is to determine from a change in the fuel pressure in the fuel passage between the shutoff valve and the fuel injection valve (hereinafter referred to as "passage fuel pressure") after a valve close command is output to the shutoff valve during fuel injection. If the shutoff valve is closed, the fuel in the fuel passage decreases as fuel injection is performed, and the passage fuel pressure drops. If the shutoff valve is stuck open, fuel continues to be supplied from the fuel tank to the fuel injection valve, so the passage fuel pressure is unlikely to drop even when fuel injection is performed. Therefore, it can be determined that the shutoff valve is stuck open based on a small drop in the passage fuel pressure.

[0005] The above-described determination of whether the shutoff valve is stuck open is preferably performed after the user has stopped the internal combustion engine, since it involves closing the shutoff valve. However, even after the user has stopped the internal combustion engine, the internal combustion engine continues to operate until the determination of whether the shutoff valve is stuck open is complete. However, there are cases where the user wishes to stop the internal combustion engine promptly after the user has stopped the internal combustion engine. [Means for solving the problem]

[0006] A control device for an internal combustion engine that solves the above-mentioned problems is a control device for an internal combustion engine mounted on a vehicle. The internal combustion engine includes a fuel tank that stores gaseous fuel, a fuel injection valve that supplies the fuel into a cylinder, a fuel passage connecting the fuel tank and the fuel injection valve, a shutoff valve disposed in the fuel passage, and a pressure sensor disposed in a portion of the fuel passage between the shutoff valve and the fuel injection valve and detecting a passage fuel pressure, which is the pressure of the fuel in that portion. The control device outputs a valve closing signal to the shutoff valve, and, when a stop operation of the internal combustion engine is performed, executes a determination process to determine whether the shutoff valve is stuck open based on an amount of decrease in the passage fuel pressure that occurs during a period from the output of the valve closing signal until a predetermined period of time has elapsed. The control device does not execute the determination process when at least one of the following conditions is met: the vehicle speed is greater than a first determination speed; and the engine rotation speed is equal to or greater than a second determination speed. [Effects of the Invention]

[0007] The above-described control device for an internal combustion engine can stop the internal combustion engine quickly after an operation to stop the internal combustion engine is performed in a situation where it is desirable to stop the internal combustion engine. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of an internal combustion engine and a control device for the internal combustion engine according to an embodiment. [Figure 2] FIG. 2 is a flowchart illustrating a procedure of a determination process executed by the control device according to an embodiment. [Figure 3] FIG. 3 is a flowchart illustrating a procedure for determining whether or not the determination process is executable, which is executed by the control device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Embodiment> An embodiment of a control device for an internal combustion engine will be described below with reference to FIGS. 1 to 3. FIG. <Configuration of Internal Combustion Engine and Control Device for Internal Combustion Engine> 1 is mounted on a vehicle. The fuel for the internal combustion engine 10 is gaseous fuel. An example of the gaseous fuel is hydrogen gas.

[0010] The internal combustion engine 10 includes an engine body 11. The engine body 11 generates power for propelling a vehicle by combusting fuel injected from fuel injection valves 13 inside each cylinder. In Fig. 1, illustrations of cylinders, spark plugs, etc. are omitted.

[0011] The internal combustion engine 10 includes a fuel tank 12, a fuel injection valve 13, a fuel passage 14, a shutoff valve 15, and a pressure sensor 16. The fuel tank 12 stores gaseous fuel. The gaseous fuel is stored in the fuel tank 12 in a compressed state. The gaseous fuel is supplied from the fuel tank 12 to the fuel injection valve 13. The fuel injection valve 13 supplies fuel into a cylinder.

[0012] Fuel passage 14 connects fuel tank 12 and fuel injection valve 13. Fuel passage 14 is composed of fuel piping 17 connected to fuel tank 12 and delivery pipe 18 connecting fuel piping 17 and fuel injection valve 13. Fuel stored in fuel tank 12 is supplied to fuel injection valve 13 via fuel piping 17 and delivery pipe 18.

[0013] The shutoff valve 15 is disposed in the fuel passage 14. The shutoff valve 15 is, for example, a solenoid valve. The shutoff valve 15 is switched between an open state and a closed state by the control device 100. The shutoff valve 15 enters an open state when it receives a valve open command from the control device 100. The shutoff valve 15 enters a closed state when it receives a valve close command from the control device 100. Specifically, when the control device 100 inputs a valve open command to a drive circuit of the shutoff valve 15, the drive circuit supplies power to the shutoff valve 15. As a result, the shutoff valve 15 enters an open state. When the control device 100 inputs a valve close command to a drive circuit of the shutoff valve 15, the drive circuit stops supplying power to the shutoff valve 15. As a result, the shutoff valve 15 enters a closed state. The shutoff valve 15 is maintained in an open state while the internal combustion engine 10 is operating. The shutoff valve 15 is maintained in a closed state while the internal combustion engine 10 is stopped. The shutoff valve 15 includes a first shutoff valve 19 and a second shutoff valve 20 .

[0014] The first shutoff valve 19 is disposed in the fuel passage 14 near the outlet of the fuel tank 12. The first shutoff valve 19 is disposed at the end of the fuel pipe 17 on the fuel tank 12 side. When the first shutoff valve 19 is in an open state, fuel is supplied from the fuel tank 12 to the fuel pipe 17. When the first shutoff valve 19 is in a closed state, fuel supply from the fuel tank 12 to the fuel pipe 17 is stopped.

[0015] The second shutoff valve 20 is disposed downstream of the first shutoff valve 19 in the fuel passage 14. The second shutoff valve 20 is disposed near the delivery pipe 18. The second shutoff valve 20 is disposed between the fuel pipe 17 and the delivery pipe 18. When the second shutoff valve 20 is in an open state, fuel is supplied from the fuel pipe 17 to the delivery pipe 18. When the second shutoff valve 20 is in a closed state, fuel supply from the fuel pipe 17 to the delivery pipe 18 is stopped.

[0016] A pressure reducing valve 21 is disposed in the fuel passage 14 between the first shutoff valve 19 and the second shutoff valve 20. The pressure reducing valve 21 adjusts the pressure of the fuel flowing into the delivery pipe 18 from the high-pressure fuel tank 12.

[0017] The pressure sensor 16 is disposed in a portion of the fuel passage 14 between the shutoff valve 15 and the fuel injection valve 13. The pressure sensor 16 detects the passage fuel pressure, which is the pressure of the fuel in the portion between the shutoff valve 15 and the fuel injection valve 13. The pressure sensor 16 outputs a detection signal relating to the detected passage fuel pressure to the control device 100.

[0018] The pressure sensor 16 includes a first pressure sensor 23 and a second pressure sensor 24. The first pressure sensor 23 is disposed in the fuel passage 14 between the first shutoff valve 19 and the fuel injection valve 13. The first pressure sensor 23 is disposed in the fuel passage 14 between the first shutoff valve 19 and the second shutoff valve 20. The first pressure sensor 23 detects a first passage fuel pressure that indicates the passage fuel pressure between the first shutoff valve 19 and the fuel injection valve 13. The second pressure sensor 24 is disposed between the second shutoff valve 20 and the fuel injection valve 13. The second pressure sensor 24 detects a second passage fuel pressure that indicates the passage fuel pressure between the second shutoff valve 20 and the fuel injection valve 13.

[0019] The internal combustion engine 10 is equipped with a temperature sensor 25. The temperature sensor 25 is disposed in a portion of the fuel passage 14 between the shutoff valve 15 and the fuel injection valve 13. The temperature sensor 25 detects the passage fuel temperature, which is the temperature of the fuel in the portion between the shutoff valve 15 and the fuel injection valve 13. The temperature sensor 25 outputs a detection signal related to the detected passage fuel temperature to the control device 100.

[0020] The temperature sensors 25 include a first temperature sensor 26 and a second temperature sensor 27. The first temperature sensor 26 is disposed between the first shutoff valve 19 and the fuel injector 13. The first temperature sensor 26 is disposed between the first shutoff valve 19 and the second shutoff valve 20. The second temperature sensor 27 is disposed between the second shutoff valve 20 and the fuel injector 13.

[0021] The control device 100 performs various controls of the internal combustion engine 10 by controlling various control objects such as the fuel injection valve 13, the first shutoff valve 19, the second shutoff valve 20, and the pressure reducing valve 21. For example, the control device 100 drives the shutoff valve 15 to open by sending a valve open signal to the shutoff valve 15, and drives the shutoff valve 15 to close by sending a valve close signal to the shutoff valve 15.

[0022] The control device 100 includes a CPU 110 and a memory 120 configured from a ROM, a RAM, etc. The CPU 110 executes a program stored in the memory 120, whereby the control device 100 performs various controls.

[0023] The control device 100 acquires various values ​​necessary for controlling the internal combustion engine 10. For example, the control device 100 acquires detection signals from the pressure sensor 16 and the temperature sensor 25. The control device 100 also acquires detection signals from various other sensors, such as an accelerator opening sensor 200, a vehicle speed sensor 300, and an ignition sensor 400. The accelerator opening sensor 200 detects the accelerator opening, which is the amount of operation of the accelerator pedal operated by the user of the vehicle equipped with the internal combustion engine 10. The vehicle speed sensor 300 detects the vehicle speed of the vehicle equipped with the internal combustion engine 10. The control device 100 acquires detection signals from the internal combustion engine 10 for calculating the engine rotation speed of the internal combustion engine 10, a detection signal of the intake air amount, and the like.

[0024] <About the judgment process> The control device 100 outputs a valve closing signal to the shutoff valve 15 and determines whether the shutoff valve 15 is stuck open based on the amount of decrease in passage fuel pressure that occurs during the period from when the valve closing signal was output until a predetermined period has elapsed. During the determination process, the fuel injection valve 13 performs fuel injection. During the determination process, fuel is continuously supplied into the cylinder from the fuel injection valve 13. The control device 100 stores in the memory 120 a determination result indicating that the shutoff valve 15 is stuck open if the amount of decrease in passage fuel pressure that occurs during the period from when the valve closing signal was output until the predetermined period has elapsed is smaller than a predetermined threshold. The predetermined threshold is set, for example, based on the amount of fuel consumed during idling of the internal combustion engine 10. The amount of fuel consumed during idling of the internal combustion engine 10 is calculated based on the number of fuel injections performed during idling, the injection time, and the passage fuel temperature.

[0025] The control device 100 may set the predetermined threshold value according to the passage fuel pressure, the passage fuel temperature, etc. at the start of the determination process. The control device 100 sets a larger predetermined threshold value as the passage fuel temperature at the start of the determination process is higher.

[0026] The determination process includes a first determination process for determining whether the first shutoff valve 19 is stuck open, and a second determination process for determining whether the second shutoff valve 20 is stuck open. The first determination process will now be described. During the execution of the first determination process, the second shutoff valve 20 is in an open state.

[0027] When the first shutoff valve 19 is in a closed state, the supply of fuel from the fuel tank 12 to the fuel passage 14 is stopped. Fuel is supplied from the fuel injection valve 13 into the cylinder when the fuel is injected from the fuel injection valve 13, but the supply of fuel from the fuel tank 12 to the fuel passage 14 is stopped, so the first passage fuel pressure drops. On the other hand, when the first shutoff valve 19 is stuck open, fuel continues to be supplied from the fuel tank 12 to the fuel passage 14, so the first passage fuel pressure does not drop, or the amount of drop in the first passage fuel pressure is smaller than when the first shutoff valve 19 is in a closed state. For this reason, it can be determined that the first shutoff valve 19 is stuck open based on the amount of drop in the first passage fuel pressure.

[0028] The second determination process will now be described. During the execution of the second determination process, the first shutoff valve 19 is preferably in a closed state. When second shutoff valve 20 is in the closed state, fuel supply from fuel pipe 17 to delivery pipe 18 is stopped. Fuel is supplied into the cylinders from fuel injection valve 13 when fuel is injected from fuel injection valve 13, but the second passage fuel pressure drops because the fuel supply from fuel pipe 17 to delivery pipe 18 is stopped. On the other hand, when second shutoff valve 20 is stuck open, fuel continues to be supplied from fuel pipe 17 to delivery pipe 18, so the second passage fuel pressure does not drop, or the drop in the second passage fuel pressure is smaller than when second shutoff valve 20 is in the closed state. Therefore, it can be determined that second shutoff valve 20 is stuck open based on the drop in the second passage fuel pressure.

[0029] The control device 100 executes the determination process when a stop operation of the internal combustion engine 10 is performed. The stop operation of the internal combustion engine 10 is, for example, when a user of the vehicle turns off the ignition switch. When a stop operation of the internal combustion engine 10 is performed, the control device 100 starts the determination process and continues operating the internal combustion engine 10 until the determination process ends. When a stop operation of the internal combustion engine 10 is performed, the control device 100 executes the determination process and then stops the internal combustion engine 10.

[0030] <Determination process flow> 2 shows a flow of a series of processes relating to the determination process executed by the control device 100. The control device 100 executes the series of processes shown in FIG. 2 in the determination process.

[0031] The control device 100 outputs a valve close command to the first shutoff valve 19 (S100). The control device 100 determines whether a first decrease amount is equal to or greater than a first threshold value (S110). The first decrease amount is the amount of decrease in the first passage fuel pressure after a first period has elapsed since the close command was output to the first shutoff valve 19 in S100. The first threshold value is set, for example, based on the amount of fuel consumed during the first period. The first period is, for example, 2 seconds.

[0032] If the first decrease amount is equal to or greater than the first threshold value (S110: YES), the control device 100 stores in the memory 120 a determination result indicating that the first shutoff valve 19 is normal and not stuck open (S120), and proceeds to the processing of S200. If the first decrease amount is not equal to or greater than the first threshold value (S110: NO), the control device 100 stores in the memory 120 a determination result indicating that the first shutoff valve 19 is abnormal and stuck open (S130), and proceeds to the processing of S200. The processing from S100 to S130 corresponds to the first determination processing.

[0033] The control device 100 outputs a valve close command to the second shutoff valve 20 (S200). The control device 100 determines whether the second decrease amount is equal to or greater than a second threshold value (S210). The second decrease amount is the amount of decrease in the second passage fuel pressure after a second period has elapsed since the valve close command was output to the second shutoff valve 20 in S200. The second threshold value is set based on the amount of fuel consumed during the second period. The second period may be the same as the first period.

[0034] If the second decrease amount is equal to or greater than the second threshold value (S210: YES), the control device 100 stores in the memory 120 a determination result indicating that the second shutoff valve 20 is normal and not stuck open (S220), and proceeds to the processing of S300. If the second decrease amount is not equal to or greater than the second threshold value (S210: NO), the control device 100 stores in the memory 120 a determination result indicating that the second shutoff valve 20 is abnormal and stuck open (S230), and proceeds to the processing of S300. The processing from S200 to S230 corresponds to the second determination processing.

[0035] The control device 100 stops the internal combustion engine 10 (S300) and ends the processing of Fig. 2. The control device 100 may output the determination results of the first shutoff valve 19 and the second shutoff valve 20 to the user of the vehicle or the like.

[0036] <When the judgment process is not executed> However, when the determination process is executed after the stop operation of the internal combustion engine 10, the operation of the internal combustion engine 10 cannot be stopped until the determination process is completed. Therefore, if the vehicle user wants to stop the operation of the internal combustion engine 10 quickly, the execution of the determination process will delay the stopping of the internal combustion engine 10. Examples of situations in which stopping the internal combustion engine 10 should take priority over executing the determination process include abnormal situations such as a vehicle accident, a vehicle fire, smoke, the generation of abnormal noise, or the generation of abnormal odor. If such an abnormal situation occurs while the vehicle is running, the vehicle user will try to stop the internal combustion engine 10. In situations in which stopping the internal combustion engine 10 should take priority over executing the determination process as described above, it is necessary to stop the internal combustion engine 10 quickly.

[0037] The control device 100 determines whether or not to execute the determination process based on at least one of the vehicle speed and the engine rotation speed. The control device 100 does not execute the determination process when at least one of the vehicle speed is greater than a first determination speed and the engine rotation speed is equal to or greater than a second determination speed. The first determination speed and the second determination speed are set to speeds corresponding to the abnormal situation described above. When a stop operation for the internal combustion engine 10 is performed and at least one of the vehicle speed being greater than the first determination speed and the engine rotation speed being equal to or greater than the second determination speed is met, the control device 100 does not execute the determination process, outputs a valve close command to the shutoff valve 15, and then stops fuel injection by the fuel injection valve 13 and fuel ignition by the spark plug, thereby stopping the internal combustion engine 10.

[0038] The first determination speed is set to a speed at which it can be determined that the vehicle is moving. The first determination speed is, for example, 0 km / h. Preferably, the control device 100 does not execute the determination process when the vehicle speed is higher than the first determination speed. When the vehicle speed is higher than the first determination speed of 0 km / h, the vehicle is moving. If an operation to stop the internal combustion engine 10 is executed while the vehicle is moving, it is highly likely that the operation to stop the internal combustion engine 10 is due to the occurrence of an abnormality.

[0039] The second determination speed is set to, for example, a speed at which it can be determined that the engine speed of the internal combustion engine 10 is equal to or greater than a predetermined speed. The engine speed is the number of revolutions per unit time of the output shaft of the internal combustion engine 10. The predetermined speed is, for example, 3000 rpm. If the engine speed of the internal combustion engine 10 is 3000 rpm or greater while the user is performing a stop operation of the internal combustion engine 10 to stop the vehicle, there is a risk that an abnormality has occurred in the internal combustion engine 10. In a situation where a stop operation of the internal combustion engine 10 is performed with the engine speed of the internal combustion engine 10 being 3000 rpm or greater, it is desirable to stop the internal combustion engine 10 promptly.

[0040] Preferably, the control device 100 does not execute the determination process when the vehicle speed is equal to or less than a first determination speed and the engine rotation speed is equal to or greater than a second determination speed. When the vehicle speed is equal to or less than 0 km / h, which is the first determination speed, the vehicle is stopped. If a stop operation of the internal combustion engine 10 is executed in a situation where the engine rotation speed is equal to or greater than the second determination speed while the vehicle is stopped, it is highly likely that the stop operation of the internal combustion engine 10 is due to the occurrence of an abnormal situation.

[0041] <Determination process flow> 3 shows the flow of a series of processes for determining whether or not the determination process can be executed by the control device 100. The control device 100 repeatedly executes the process of FIG.

[0042] The control device 100 determines whether or not a stop operation has been performed for the internal combustion engine 10 (S400). If a stop operation for the internal combustion engine 10 has not been performed (S400: NO), the control device 100 ends the processing of FIG.

[0043] When the operation to stop the internal combustion engine 10 is executed (S400: YES), the control device 100 determines whether the vehicle speed is greater than a first determination speed (S410). When the vehicle speed is greater than the first determination speed (S410: YES), the control device 100 outputs a valve close command to the first shutoff valve 19 and the second shutoff valve 20 (S420), and then stops the internal combustion engine 10 (S430), and ends the processing of FIG. 3 without executing the determination processing.

[0044] If the vehicle speed is not greater than the first judgment speed (S410: NO), the control device 100 determines whether the engine rotation speed is equal to or greater than the second judgment speed (S440). If the engine rotation speed is equal to or greater than the second judgment speed (S440: YES), the control device 100 outputs a valve close command to the first shutoff valve 19 and the second shutoff valve 20 (S420), and then stops the internal combustion engine 10 (S430), and ends the processing of FIG. 3 without executing the judgment processing.

[0045] If the engine rotation speed is not equal to or higher than the second determination speed (S440: NO), the control device 100 executes a determination process (S450) and ends the process in Fig. 3. The determination process executed in S450 is a series of processes shown in Fig. 2.

[0046] <Actions and Effects of This Embodiment> (1) A situation in which it is desirable to stop the internal combustion engine 10 quickly is when the vehicle speed of the vehicle equipped with the internal combustion engine 10 is higher than a first judgment speed or when the engine speed is equal to or higher than a second judgment speed and the user of the vehicle performs an operation to stop the internal combustion engine 10. In the above-described control device 100, in a situation in which it is desirable to stop the internal combustion engine 10, stopping the internal combustion engine 10 takes priority over the judgment process. Therefore, in a situation in which it is desirable to stop the internal combustion engine 10, the control device 100 can stop the internal combustion engine 10 quickly after performing the stop operation of the internal combustion engine 10.

[0047] (2) In a situation where an operation to stop the internal combustion engine 10 is executed while the vehicle is traveling, it is desirable to stop the internal combustion engine 10 as soon as possible. In the above-described control device 100, when an operation to stop the internal combustion engine 10 is executed, the determination process is not executed if the vehicle speed is greater than 0 km / h. In this way, the control device 100 can more appropriately determine a situation where it is desirable to quickly stop the internal combustion engine 10 based on the vehicle speed.

[0048] (3) In a situation where a stop operation of the internal combustion engine 10 is executed while the engine rotation speed of the internal combustion engine 10 is very high, it is desirable to stop the internal combustion engine 10 early. In the above-described control device 100, when a stop operation of the internal combustion engine 10 is executed, the determination process is not executed if the engine rotation speed is equal to or higher than the second determination speed. In this way, the control device 100 can more appropriately determine a situation where it is desirable to quickly stop the internal combustion engine 10 based on the engine rotation speed.

[0049] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0050] The internal combustion engine 10 may be configured to have only one of the first shutoff valve 19 and the second shutoff valve 20 as the shutoff valve. When the control device 100 executes the determination process, only one of the first determination process and the second determination process may be executed as the determination process.

[0051] When the operation to stop the internal combustion engine 10 is performed, if the vehicle speed is equal to or lower than the first determination speed, the determination process may be performed regardless of the engine rotation speed. In the embodiment, an example was shown in which the execution of the determination process was determined based on both the vehicle speed and the engine rotation speed, but the execution of the determination process may also be determined based on either the vehicle speed or the engine rotation speed. If an operation to stop the internal combustion engine 10 is performed while the vehicle is stopped and the engine rotation speed is equal to or higher than the second determination speed, for example, there is a risk that an abnormality has occurred in the internal combustion engine 10. On the other hand, if an operation to stop the internal combustion engine 10 is performed while the vehicle is traveling and the engine rotation speed is equal to or higher than the second determination speed, there is a risk that the user will panic due to the occurrence of an abnormality and continue to depress the accelerator pedal. [Explanation of symbols]

[0052] 10...Internal combustion engine 11...Engine body 12...Fuel tank 13...Fuel injection valve 14…Fuel passage 15...Shut-off valve 16...Pressure sensor 17…Fuel piping 18...Delivery pipe 19...First shutoff valve 20...Second shutoff valve 21...Reducing valve 23...First pressure sensor 24...Second pressure sensor 25...Temperature sensor 26...First temperature sensor 27...Second temperature sensor 100...Control device 110...CPU 120...Memory 200...Accelerator opening sensor 300...Vehicle speed sensor 400...Ignition sensor

Claims

[Claim 1] A control device for an internal combustion engine mounted on a vehicle, The internal combustion engine includes: a fuel tank for storing gaseous fuel; a fuel injection valve that supplies the fuel into a cylinder; a fuel passage connecting the fuel tank and the fuel injection valve; a shutoff valve disposed in the fuel passage; a pressure sensor disposed in a portion of the fuel passage between the shutoff valve and the fuel injection valve, for detecting a passage fuel pressure that is the pressure of the fuel in that portion, The control device a valve closing signal is output to the shutoff valve, and a determination process is executed when a stop operation of the internal combustion engine is performed, to determine whether the shutoff valve is stuck open based on an amount of decrease in the passage fuel pressure that occurs during a period of time that has elapsed since the output of the valve closing signal until the period of time that has elapsed reaches a predetermined specified period; When at least one of the following is true: the vehicle speed is greater than the first determination speed; and the engine rotation speed is equal to or greater than the second determination speed, the determination process is not executed. Control device for internal combustion engines.

Images