JP2012013050A - Fuel pump control device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the deterioration of the startability (starting failure) when starting the engine while reducing power consumption quantity of the fuel pump when the engine is automatically stopped during idling stop.SOLUTION: The fuel pump 31 is stopped during the automatically of the engine (when the engine 11 is automatically stopped), thereafter it is predicted whether the engine 11 is restarted based on the inter-vehicle distance of the own vehicle and a leading vehicle detected by an inter-vehicle distance sensor 37 before restart requirement is generated during the automatic stop of the engine and the fuel pump 31 is driven when it is predicted that the engine 11 is restarted. Thereby, the power consumption is reduced by keeping the fuel pump 31 in the stopped condition a little bit before the engine 11 is restarted and after the engine is automatically stopped (when it is predicted that the engine is restarted), and the fuel pressure is raised to a proper value (the fuel pressure required for starting) until the time when restarting the engine by driving the fuel pump 31 a little bit before the engine 11 is restarted.

Description

  The present invention relates to a fuel pump control device for an internal combustion engine having an idle stop control function.

  In recent years, some vehicles equipped with an internal combustion engine employ an idle stop control system for the purpose of reducing fuel consumption and exhaust emissions. In this idle stop control system, for example, when the driver stops the vehicle while the internal combustion engine is operating and an automatic stop request is generated, the internal combustion engine is automatically stopped, and then the internal combustion engine is automatically stopped (idle The internal combustion engine is automatically restarted when a restart request is generated by the driver performing an operation to start the vehicle during the stop).

  By the way, during the automatic stop of the internal combustion engine, the power generation of the generator (alternator) driven by the power of the internal combustion engine is also stopped. For this reason, if the electric fuel pump is continuously driven during the automatic stop of the internal combustion engine, the power consumption of the fuel pump during the automatic stop of the internal combustion engine increases. May cause.

  On the other hand, if the fuel pump is kept stopped during the automatic stop of the internal combustion engine, the fuel pressure (fuel pressure) decreases during the automatic stop of the internal combustion engine. Cannot be quickly raised to an appropriate value (fuel pressure required for starting), and the fuel pressure may be insufficient and startability may be reduced.

  As a countermeasure against this, as described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2004-278365), the fuel pump is stopped when the internal combustion engine is automatically stopped, and thereafter, every predetermined time or fuel pressure during the automatic stop of the internal combustion engine. In some cases, the fuel pressure is maintained at a predetermined value or more during the automatic stop of the internal combustion engine by driving the fuel pump each time the fuel pressure falls below a predetermined value.

  Further, in a system including a high-pressure fuel pump driven by the power of the internal combustion engine, as described in Patent Document 2 (Japanese Patent Laid-Open No. 2006-348908), the internal combustion engine is automatically stopped when the internal combustion engine is automatically stopped. In some cases, the fuel pressure is increased by driving a high-pressure fuel pump using the inertial rotation when the is rotating with inertia.

JP 2004-278365 A JP 2006-348908 A

  However, in the technique of Patent Document 1, it is necessary to drive the fuel pump every predetermined time or every time the fuel pressure falls below a predetermined value during the automatic stop (idle stop) of the internal combustion engine. There is a drawback that the power consumption of the fuel pump during the automatic stop of the engine cannot be effectively reduced.

  The technique of Patent Document 2 is a technique related to a high-pressure fuel pump driven by the power of the internal combustion engine, and is not related to an electric fuel pump (low-pressure fuel pump). The problem of pump power consumption cannot be solved.

  Therefore, the problem to be solved by the present invention is to prevent a decrease in startability (starting failure) when restarting the internal combustion engine while reducing the power consumption of the fuel pump during the automatic stop of the internal combustion engine. An object of the present invention is to provide a fuel pump control device for an internal combustion engine.

  In order to solve the above-mentioned problems, an invention according to claim 1 is directed to an electric fuel pump that supplies fuel to an internal combustion engine and to automatically stop the internal combustion engine when an automatic stop request is generated during operation of the internal combustion engine. Internal combustion engine comprising: an idle stop control means for restarting the internal combustion engine when a restart request is generated during the automatic stop of the internal combustion engine; and a fuel pump control means for stopping the fuel pump when the internal combustion engine is automatically stopped In the engine fuel pump control device, the fuel pump control means predicts whether or not the internal combustion engine is restarted before the restart request is generated during the automatic stop of the internal combustion engine, and the internal combustion engine is restarted. The fuel pump is driven when it is predicted.

  In this configuration, the fuel pump is stopped when the internal combustion engine is automatically stopped (when the internal combustion engine is automatically stopped), and then the internal combustion engine is restarted before the restart request is generated during the automatic stop of the internal combustion engine. The fuel pump can be driven when it is predicted that the internal combustion engine will be restarted. As a result, the fuel pump can be maintained in a stopped state from when the internal combustion engine is automatically stopped until shortly before the internal combustion engine is restarted (when it is predicted that the internal combustion engine will be restarted). The power consumption of the pump can be effectively reduced. Moreover, since the fuel pump can be driven shortly before the internal combustion engine is restarted, the fuel pressure (fuel pressure) can be increased to an appropriate value (fuel pressure required for starting) by the time of restarting the internal combustion engine. This makes it possible to prevent a decrease in startability (starting failure) when restarting the internal combustion engine.

  A specific method for predicting whether or not the internal combustion engine is restarted before the restart request is generated is, for example, an inter-vehicle distance for detecting the inter-vehicle distance between the host vehicle and the preceding vehicle as in claim 2. A detection unit may be provided to predict whether or not the internal combustion engine is restarted based on the inter-vehicle distance between the host vehicle and the preceding vehicle detected by the inter-vehicle distance detection unit during the automatic stop of the internal combustion engine. For example, when the inter-vehicle distance between the host vehicle and the preceding vehicle becomes equal to or greater than a predetermined value during the automatic stop of the internal combustion engine, it can be determined that the preceding vehicle has started, so the driver is about to start the host vehicle soon. By performing the operation, it can be predicted that a restart request is generated and the internal combustion engine is restarted. Therefore, if the inter-vehicle distance between the host vehicle and the preceding vehicle is monitored during the automatic stop of the internal combustion engine, it can be predicted whether the internal combustion engine will be restarted before the restart request is generated.

  Further, according to a third aspect of the present invention, there is provided traffic information receiving means for receiving traffic information transmitted from a predetermined communication device, and the internal combustion engine is based on traffic information received by the traffic information receiving means during automatic stop of the internal combustion engine. It may be predicted whether or not will be restarted. For example, when the remaining time until the traffic light in front of the internal combustion engine automatically switches from a red signal to a green signal falls below a predetermined value, the traffic light will soon switch to a green signal and the driver will start the vehicle. It can be predicted that a restart request is generated and the internal combustion engine is restarted. Therefore, if the traffic information received during the automatic stop of the internal combustion engine (for example, the remaining time until the front traffic light switches from the red signal to the blue signal) is monitored, the internal combustion engine is restarted before the restart request is generated. Whether or not it can be predicted.

  Further, according to the fourth aspect of the present invention, the operation detection means for detecting the operation of the driver is provided, and it is predicted whether or not the internal combustion engine is restarted based on the output signal of the operation detection means during the automatic stop of the internal combustion engine. You may make it do. For example, when the brake operation amount (depression amount) starts to decrease during the automatic stop of the internal combustion engine, the brake depression is released soon, a restart request is generated, and the internal combustion engine is restarted. Predictable. Therefore, if the output signal of the operation detection means (for example, a brake sensor for detecting the brake operation amount) is monitored during the automatic stop of the internal combustion engine, it is determined whether or not the internal combustion engine is restarted before the restart request is generated. Can be predicted.

FIG. 1 is a diagram showing a schematic configuration of an engine control system in Embodiment 1 of the present invention. FIG. 2 is a flowchart for explaining the flow of processing of the fuel pump control routine of the first embodiment. FIG. 3 is a flowchart for explaining the flow of processing of the fuel pump control routine of the second embodiment. FIG. 4 is a time chart illustrating an execution example of fuel pump control according to the third embodiment. FIG. 5 is a flowchart for explaining the flow of processing of the fuel pump control routine of the third embodiment.

  Hereinafter, some embodiments embodying the mode for carrying out the present invention will be described.

A first embodiment of the present invention will be described with reference to FIGS.
First, a schematic configuration of the entire engine control system will be described with reference to FIG.
An air cleaner 13 is provided at the most upstream portion of an intake pipe 12 of an engine 11 that is an internal combustion engine mounted on a vehicle, and an air flow meter 14 that detects an intake air amount is provided downstream of the air cleaner 13. . A throttle valve 16 whose opening is adjusted by a motor 15 and a throttle opening sensor 17 for detecting the opening (throttle opening) of the throttle valve 16 are provided on the downstream side of the air flow meter 14.

  Further, a surge tank 18 is provided on the downstream side of the throttle valve 16, and an intake pipe pressure sensor 19 for detecting the intake pipe pressure is provided in the surge tank 18. The surge tank 18 is provided with an intake manifold 20 that introduces air into each cylinder of the engine 11, and a fuel injection valve that injects fuel toward the intake port in the vicinity of the intake port of the intake manifold 20 of each cylinder. 21 is attached. An ignition plug 22 is attached to the cylinder head of the engine 11 for each cylinder, and the air-fuel mixture in the cylinder is ignited by spark discharge of the ignition plug 22 of each cylinder.

  On the other hand, the exhaust pipe 23 of the engine 11 is provided with an exhaust gas sensor 24 (air-fuel ratio sensor, oxygen sensor, etc.) for detecting the air-fuel ratio or rich / lean of the exhaust gas. A catalyst 25 such as a three-way catalyst for purifying gas is provided.

  A cooling water temperature sensor 26 that detects the cooling water temperature and a knock sensor 27 that detects knocking are attached to the cylinder block of the engine 11. A crank angle sensor 29 that outputs a pulse signal every time the crankshaft 28 rotates by a predetermined crank angle is attached to the outer peripheral side of the crankshaft 28, and the crank angle and the engine are determined based on the output signal of the crank angle sensor 29. The rotation speed is detected.

  A fuel pump 31 that pumps up fuel is provided in the fuel tank 30. The fuel pump 31 is driven by an electric motor (not shown) that uses a battery (not shown) as a power source. The fuel discharged from the fuel pump 31 is sent to the delivery pipe 33 through the fuel pipe 32 and is distributed from the delivery pipe 33 to the fuel injection valve 21 of each cylinder. A fuel filter 34 and a pressure regulator 35 are connected in the vicinity of the fuel pump 31 in the fuel pipe 32, and the discharge pressure of the fuel pump 31 is regulated to a predetermined pressure by the pressure regulator 35, and surplus fuel exceeding that pressure The minute amount is returned into the fuel tank 30 by the fuel return pipe 36.

  An inter-vehicle distance sensor 37 (inter-vehicle distance detecting means) that detects the inter-vehicle distance between the host vehicle and the preceding vehicle is attached to the front surface of the vehicle. As the inter-vehicle distance sensor 37, for example, a laser radar sensor that detects the inter-vehicle distance using a millimeter wave laser is used. Instead of the laser radar sensor, an inter-vehicle distance sensor that detects an inter-vehicle distance using radio waves, sound waves, or the like may be used.

  Outputs of the various sensors described above are input to an electronic control circuit (hereinafter referred to as “ECU”) 38. The ECU 38 is mainly composed of a microcomputer, and executes various engine control programs stored in a built-in ROM (storage medium), so that the fuel injection amount and the ignition timing are determined according to the engine operating state. The throttle opening (intake air amount) and the like are controlled.

  The ECU 38 stops fuel injection (fuel cut) and automatically stops combustion of the engine 11 when an automatic stop request (idle stop request) is generated when the driver stops the vehicle during engine operation. Let In addition, you may make it expand the driving | operation area | region (the driving | operation area | region where the automatic stop request | requirement generate | occur | produces an automatic stop request | requirement) to which the engine 11 is stopped to the deceleration area | region at the low speed which may reach a vehicle stop during vehicle travel.

  After that, when the driver performs an operation to start or accelerate the vehicle (for example, release brake depression, accelerator depression operation, etc.) while the engine is automatically stopped (idle stop), The injection is resumed and the engine 11 is automatically restarted. In addition, the engine 11 may be restarted when a restart request is generated from a control system of an in-vehicle device such as a battery charge control system or an air conditioner.

  By the way, during the engine automatic stop, the power generation of the generator (alternator) driven by the power of the engine 11 is also stopped. For this reason, if the electric fuel pump 31 is continuously driven during the engine automatic stop, the power consumption of the fuel pump 31 during the engine automatic stop increases, so that the battery power may be consumed and the so-called battery may increase. There is sex.

  On the other hand, if the fuel pump 31 is maintained in the stopped state during the engine automatic stop, the fuel pressure (fuel pressure) decreases during the engine automatic stop. The fuel pressure cannot be increased to the value (fuel pressure required for starting), and there is a possibility that the starting performance is lowered due to insufficient fuel pressure.

  Therefore, the ECU 38 stops the fuel pump 31 when the engine is automatically stopped (when the engine 11 is automatically stopped), and then restarts the engine 11 before the restart request is generated during the automatic engine stop. When the engine 11 is predicted to be restarted, the fuel pump 31 is driven. As a result, the fuel pump 31 is maintained in a stopped state from when the engine is automatically stopped until shortly before the engine 11 is restarted (when it is predicted that the engine 11 is restarted). The fuel pump 31 is driven slightly before starting to increase the fuel pressure to an appropriate value by the time of engine restart.

  In the first embodiment, as a specific method for predicting whether or not the engine 11 is restarted before the restart request is generated, the host vehicle and the preceding vehicle detected by the inter-vehicle distance sensor 37 during the automatic engine stop. Whether or not the engine 11 is restarted is predicted based on the inter-vehicle distance. For example, when the inter-vehicle distance between the host vehicle and the preceding vehicle becomes equal to or greater than a predetermined value while the engine is automatically stopped, it can be determined that the preceding vehicle has started, so the driver will soon perform an operation to start the host vehicle. Then, it can be predicted that a restart request is generated and the engine 11 is restarted. Therefore, if the inter-vehicle distance between the host vehicle and the preceding vehicle is monitored while the engine is automatically stopped, it can be predicted whether or not the engine 11 is restarted before the restart request is generated.

The fuel pump control of the first embodiment described above is executed by the ECU 38 according to the routine of FIG. The processing contents of this routine will be described below.
The fuel pump control routine shown in FIG. 2 is repeatedly executed at a predetermined cycle while the ECU 38 is powered on, and serves as an idle stop control means and a fuel pump control means in the claims.

When this routine is started, first, in step 101, it is determined whether or not an automatic stop condition is satisfied during engine operation (an automatic stop request is generated). Here, the automatic stop condition is satisfied when, for example, the accelerator off (accelerator fully closed), the brake on (brake is depressed), and the vehicle speed satisfy all the conditions such as a predetermined value or less. The automatic stop condition may be changed as appropriate.
If it is determined in step 101 that the automatic stop condition is not satisfied, the process proceeds to step 102 and the fuel pump 31 is maintained in the driving state.

  Thereafter, when it is determined in step 101 that an automatic stop condition is satisfied during engine operation (an automatic stop request is generated), the process proceeds to step 103 to stop fuel injection (fuel cut) and After automatically stopping the combustion, the routine proceeds to step 104 where the fuel pump 31 is stopped.

  Thereafter, the process proceeds to step 105, the inter-vehicle distance between the host vehicle and the preceding vehicle detected by the inter-vehicle distance sensor 37 is acquired, and then the process proceeds to step 106, in which the inter-vehicle distance between the host vehicle and the preceding vehicle is a predetermined value or more. Whether or not the engine 11 is restarted is predicted based on whether or not.

  If it is determined in step 106 that the distance between the host vehicle and the preceding vehicle is shorter than the predetermined value, it is predicted that the engine 11 will not be restarted, and the process returns to step 105 to return to the preceding vehicle and the preceding vehicle. The process of acquiring the inter-vehicle distance from the vehicle and determining whether the inter-vehicle distance is equal to or greater than a predetermined value (steps 105 and 106) is repeated.

  Thereafter, if it is determined in step 106 that the distance between the host vehicle and the preceding vehicle is greater than or equal to a predetermined value, it can be determined that the preceding vehicle has started, so the driver will start the host vehicle soon. It is predicted that the engine 11 will be restarted when an operation to be performed is performed and a restart request is generated. Then, when the engine 11 is predicted to be restarted (that is, when it is determined that the distance between the host vehicle and the preceding vehicle is greater than or equal to a predetermined value), the routine proceeds to step 107 and the fuel pump 31 is driven.

Thereafter, the process proceeds to step 108, and it is determined whether or not a restart condition is satisfied (restart request is generated) during the automatic engine stop. Here, the restart condition is satisfied, for example, when one of the conditions of brake off (the brake is not depressed), accelerator on (the accelerator is depressed), or the like is satisfied. Note that the restart condition may be changed as appropriate.
If it is determined in step 108 that the restart condition is not satisfied, the process waits until the restart condition is satisfied.

  Thereafter, when it is determined in step 108 that the restart condition is satisfied during the automatic engine stop (restart request is generated), the process proceeds to step 109, where the starter is turned on and fuel injection is restarted to restart the engine. 11 is automatically restarted.

  In the first embodiment described above, the fuel pump 31 is stopped when the engine is automatically stopped, and then the distance between the host vehicle and the preceding vehicle detected by the inter-vehicle distance sensor 37 before the restart request is generated while the engine is automatically stopped. Whether or not the engine 11 is restarted is predicted based on the distance, and the fuel pump 31 is driven when it is predicted that the engine 11 will be restarted. As a result, the fuel pump 31 can be maintained in a stopped state from when the engine is automatically stopped until slightly before the engine 11 is restarted (when it is predicted that the engine 11 is restarted). The power consumption can be effectively reduced. Moreover, since the fuel pump 31 can be driven shortly before the engine 11 is restarted, the fuel pressure can be increased to an appropriate value by the time of engine restart, and the startability at the time of engine restart is reduced. (Starting failure) can be prevented.

  Next, Embodiment 2 of the present invention will be described with reference to FIG. However, description of substantially the same parts as those in the first embodiment will be omitted or simplified, and different parts from the first embodiment will be mainly described.

  In the second embodiment, a traffic information receiving device (traffic information receiving means) (not shown) is provided, and this traffic information receiving device transmits traffic information (for example, a communication device installed in a traffic light) (for example, a communication device). The remaining time until the front traffic light switches from a red signal to a green signal is received.

  3 is executed by the ECU 38 to be described later, the engine 11 is restarted based on the traffic information received by the traffic information receiving device before the restart request is generated while the engine is automatically stopped. Predict whether or not. For example, when the remaining time until the traffic signal ahead changes from a red traffic light to a green traffic light becomes less than a predetermined value during automatic engine stop, the traffic light will soon switch to a green traffic light and the driver will try to start the vehicle. By performing the operation, it can be predicted that a restart request is generated and the engine 11 is restarted. Therefore, if the traffic information received during the automatic engine stop (for example, the remaining time until the traffic signal ahead switches from a red signal to a green signal) is monitored, whether or not the engine 11 is restarted before the restart request is generated. Can be predicted.

  The routine of FIG. 3 is obtained by changing the processing of steps 105 and 106 of the routine of FIG. 2 described in the first embodiment to the processing of steps 105a and 106a, and the processing of other steps is the same as that of FIG. It is.

  In the fuel pump control routine of FIG. 3, when an automatic stop condition is satisfied during engine operation (an automatic stop request is generated), the engine 11 is automatically stopped and the fuel pump 31 is stopped (steps 101 to 104). .

  Thereafter, the process proceeds to step 105a, and after obtaining the traffic information received by the traffic information receiving device (for example, the remaining time until the front traffic light switches from the red signal to the green traffic light), the process proceeds to step 106a, where the traffic signal ahead is Whether or not the engine 11 is restarted is predicted based on whether or not the remaining time until switching to the green light is a predetermined value or less.

  If it is determined in step 106a that the remaining time until the traffic signal ahead changes from a red signal to a blue signal is longer than a predetermined value, it is predicted that the engine 11 will not be restarted, and the process returns to step 105a. The remaining time until the front traffic light switches from the red signal to the blue signal is acquired, and the process of determining whether the remaining time is equal to or less than the predetermined value (steps 105a and 106a) is repeated.

After that, if it is determined in step 106a that the remaining time until the traffic signal ahead changes from a red signal to a green signal is less than or equal to a predetermined value, the traffic signal will soon switch to a green signal and the driver It is predicted that the engine 11 is restarted when an operation to start is performed and a restart request is generated. Then, when it is predicted that the engine 11 will be restarted (that is, when it is determined that the remaining time until the front traffic light switches from the red signal to the green signal is less than or equal to the predetermined value), the routine proceeds to step 107, where 31 is driven.
Thereafter, the engine 11 is restarted when a restart condition is satisfied during the automatic engine stop (a restart request is generated) (steps 108 and 109).

  In the second embodiment described above, based on the traffic information received by the traffic information receiving device before the restart request is generated while the engine is automatically stopped (for example, the remaining time until the front traffic light switches from a red signal to a green signal). Thus, the fuel pump 31 is driven when the engine 11 is predicted to be restarted and the engine 11 is predicted to be restarted, so that substantially the same effect as the first embodiment can be obtained. it can.

  In the second embodiment, whether or not the engine 11 is restarted based on traffic information transmitted from a communication device installed in the traffic light (for example, the remaining time until the traffic light ahead switches from a red signal to a green signal). However, the present invention is not limited to this, for example, traffic information transmitted from a communication device installed on a road or an intersection (for example, the remaining time until the front traffic light switches from a red signal to a green signal, Traffic information transmitted from the other vehicle and / or the navigation device of the own vehicle, or whether the engine 11 is restarted based on traffic information, distance to signalized intersection, etc. Whether or not the engine 11 is restarted may be predicted based on position information, map information, and the like.

  Next, Embodiment 3 of the present invention will be described with reference to FIGS. However, description of substantially the same parts as those in the first embodiment will be omitted or simplified, and different parts from the first embodiment will be mainly described.

  In the third embodiment, a brake sensor (operation detection means) (not shown) is provided, and the brake operation amount of the driver is detected by this brake sensor. As shown in FIG. 4, at a time point t on when the output signal (brake operation amount) of the brake sensor becomes equal to or higher than a predetermined brake on determination value, the brake signal is turned on (ON), and the output signal of the brake sensor is At the time toff when the brake-off determination value is reached, the brake signal is switched off (OFF). Further, when the brake signal is switched from on to off during the engine automatic stop, the restart condition is satisfied and a restart request is generated.

  Then, by executing a fuel pump control routine of FIG. 5 described later by the ECU 38, the engine 11 is restarted based on the output signal (brake operation amount) of the brake sensor before the restart request is generated during the automatic engine stop. Predict whether or not For example, as shown in FIG. 4, when the amount of change in the output signal of the brake sensor (for example, the difference between the current value and the previous value) becomes equal to or less than a predetermined determination value during automatic engine stop, Since it can be determined that the operation amount (depression amount) of the engine has started to decrease, the brake depression is soon released (the brake signal is switched off), a restart request is generated, and the engine 11 is restarted. Can be predicted. Therefore, if the output signal of the brake sensor is monitored during the engine automatic stop, it can be predicted whether or not the engine 11 is restarted before the restart request is generated.

  The routine of FIG. 5 is obtained by changing the processing of steps 105 and 106 of the routine of FIG. 2 described in the first embodiment to the processing of steps 105b and 106b, and the processing of each other step is the same as FIG. It is.

  In the fuel pump control routine of FIG. 5, the engine 11 is automatically stopped and the fuel pump 31 is stopped (steps 101 to 104) when an automatic stop condition is satisfied during engine operation (an automatic stop request is generated). .

  Thereafter, the process proceeds to step 105b, and after calculating the change amount of the output signal of the brake sensor (for example, the difference between the current value and the previous value), the process proceeds to step 106b and the change amount of the output signal of the brake sensor is equal to or less than a predetermined determination value. It is predicted whether or not the engine 11 will be restarted depending on whether or not.

  If it is determined in step 106b that the amount of change in the output signal of the brake sensor is larger than the determination value, it is predicted that the engine 11 will not be restarted, and the process returns to step 105b to output the output signal of the brake sensor. The change amount is calculated, and the process of determining whether or not the change amount is equal to or less than the determination value (steps 105b and 106b) is repeated.

After that, if it is determined in step 106b that the change amount of the output signal of the brake sensor is equal to or less than the determination value, it can be determined that the brake operation amount (depression amount) has started to decrease, so soon It is predicted that the depression is released (the brake signal is switched off), a restart request is generated, and the engine 11 is restarted. Then, when the engine 11 is predicted to be restarted (that is, when the change amount of the output signal of the brake sensor is determined to be equal to or less than the determination value), the process proceeds to step 107 and the fuel pump 31 is driven.
Thereafter, the engine 11 is restarted when a restart condition is satisfied during the automatic engine stop (a restart request is generated) (steps 108 and 109).

  In the third embodiment described above, it is predicted whether or not the engine 11 is restarted based on the output signal of the brake sensor before the restart request is generated while the engine is automatically stopped, and the engine 11 is restarted. Since the fuel pump 31 is driven when it is predicted that the same effect as that of the first embodiment can be obtained.

  In the third embodiment, it is predicted whether or not the engine 11 is restarted based on the output signal of the brake sensor. However, the present invention is not limited to this, and operation detection means other than the brake sensor (for example, Whether or not the engine 11 is restarted may be predicted based on an output signal of an accelerator sensor, a shift sensor, or the like.

  In addition, the present invention may be implemented by appropriately combining the above first to third embodiments. That is, using two or three of the inter-vehicle distance between the host vehicle and the preceding vehicle detected by the inter-vehicle distance detecting means, the traffic information received by the traffic information receiving means, and the output signal of the operation detecting means, It may be predicted whether 11 will be restarted.

  In addition, the present invention is not limited to the intake port injection type engine as shown in FIG. 1, but includes an in-cylinder injection type engine, and both an intake port injection fuel injection valve and an in-cylinder injection fuel injection valve. It can also be applied to dual-injection engines.

  DESCRIPTION OF SYMBOLS 11 ... Engine (internal combustion engine), 12 ... Intake pipe, 16 ... Throttle valve, 21 ... Fuel injection valve, 22 ... Spark plug, 23 ... Exhaust pipe, 30 ... Fuel tank, 31 ... Fuel pump, 32 ... Fuel piping, 37 ... inter-vehicle distance sensor (inter-vehicle distance detection means), 38 ... ECU (idle stop control means, fuel pump control means)

Claims (4)

An electric fuel pump for supplying fuel to the internal combustion engine, and an automatic stop request when an automatic stop request is generated during operation of the internal combustion engine, and a restart request is generated during the automatic stop of the internal combustion engine A fuel pump control device for an internal combustion engine comprising: an idle stop control means for restarting the internal combustion engine when the engine is stopped; and a fuel pump control means for stopping the fuel pump when the internal combustion engine is automatically stopped.
The fuel pump control means predicts whether or not the internal combustion engine is restarted before the restart request is generated during the automatic stop of the internal combustion engine, and predicts that the internal combustion engine is restarted A fuel pump control device for an internal combustion engine, wherein the fuel pump is sometimes driven. An inter-vehicle distance detecting means for detecting the inter-vehicle distance between the host vehicle and the preceding vehicle;
The fuel pump control means predicts whether or not the internal combustion engine is restarted based on the inter-vehicle distance between the host vehicle and the preceding vehicle detected by the inter-vehicle distance detection means during the automatic stop of the internal combustion engine. The fuel pump control device for an internal combustion engine according to claim 1, comprising: Comprising traffic information receiving means for receiving traffic information transmitted from a predetermined communication device;
The fuel pump control means includes means for predicting whether or not the internal combustion engine is restarted based on traffic information received by the traffic information receiving means during the automatic stop of the internal combustion engine. The fuel pump control device for an internal combustion engine according to claim 1 or 2. Comprising operation detection means for detecting the operation of the driver;
2. The fuel pump control means includes means for predicting whether or not the internal combustion engine is restarted based on an output signal of the operation detection means during the automatic stop of the internal combustion engine. A fuel pump control device for an internal combustion engine according to any one of claims 1 to 3.

Images