JP2008286127A - Vehicle control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle control device for actualizing a vehicle which functions to continuously drive an internal combustion engine only for a predetermined period even when stop instructing operation of the internal combustion engine is performed with off-operation of an ignition switch, e.g., and which does not make an occupant aware of the existence of this kind of function, thus improving the practicality of this kind of vehicle. <P>SOLUTION: At the time when off-operation of the ignition switch is performed by a driver, if the range position of a transmission is neither "a parking range position" nor "a neutral range position", "internal combustion engine stop relaying control" is prohibited. At almost the same time when the off-operation of the ignition switch 110 is performed, an ignition device 50 and an injection device 20 are stopped and the drive of the engine is stopped. This avoids the event that the engine is driven in the condition that the driving force of the engine may be transmitted to driving wheels. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle control apparatus represented by an automobile. In particular, according to the present invention, when an internal combustion engine (engine) mounted on a vehicle is stopped, the internal combustion engine is driven only for a predetermined period even if an internal combustion engine stop instruction operation is performed by turning off an ignition switch or the like. It is related with the improvement of the control action with respect to the vehicle which continued (it delays a stop).

  Conventionally, as disclosed in, for example, Patent Document 1 and Patent Document 2 below, the engine is driven only for a certain period of time (for example, about 2 to 3 seconds) after the driver (driver) turns off the ignition switch. Vehicles that continue are known. In other words, even if the ignition switch is turned off, the engine operation is continued by continuing the ignition operation of the ignition plug and the fuel injection operation of the injector (at least one of them continues), and then the ignition operation of the ignition plug is stopped ( Ignition cut) and stop of the fuel injection operation of the injector (fuel cut) are performed to stop the engine. Hereinafter, this control is referred to as “internal combustion engine stop delay control”.

The purpose of performing such “internal combustion engine stop delay control” is various, but as a typical one, for example, as disclosed in Patent Document 1, the piston position at the time of engine stop is set at the time of engine restart. This is for setting the position where the startability is good or as disclosed in Patent Document 2, by continuing the ignition operation of the spark plug, the residual gas in the cylinder is burned and the engine is stopped. In order to prevent the air-fuel mixture from remaining in the subsequent cylinder and improve engine startability and prevent deterioration of exhaust properties.
JP-A-11-107793 JP 2000-104651 A

  However, in a vehicle that can execute the “internal combustion engine stop delay control”, there is still a problem to be solved in order to improve its practicality. That is, even if the vehicle has this “internal combustion engine stop delay control” function, the vehicle does not have this “internal combustion engine stop delay control” function (a vehicle that stops the engine substantially simultaneously with the ignition switch OFF operation). If it can not be handled equally, it will not be possible to increase the practicality of this type of vehicle. In other words, it can be said that the practicality of this type of vehicle cannot be improved unless it is a vehicle that does not make the occupant aware of having the "internal combustion engine stop delay control" function. In the following, the situation that has been an adverse effect on enhancing the practicality will be described in detail.

  For example, as a general engine stop operation, the vehicle driver turns off the ignition switch while depressing the brake pedal (brake ON operation), and immediately releases the brake pedal depression operation (brake OFF operation). The operation is performed. However, in this type of vehicle (a vehicle having an “internal combustion engine stop delay control” function), the engine continues to be driven even after the ignition switch is turned off. There is a possibility that the engine is still running at the time of release. Therefore, when the driver releases the brake pedal depression operation, the transmission range position is set to P (parking range position) or N (neutral range position), and the driving force of the engine is not transmitted to the drive wheels. There was annoyance that had to be confirmed.

  The present invention has been made in view of such a point, and an object of the present invention is to drive the internal combustion engine only for a predetermined period even when the stop instruction operation of the internal combustion engine is performed by turning off the ignition switch or the like. Provided is a vehicle control device capable of enhancing the practicality of this type of vehicle by realizing a vehicle that does not make an occupant aware that this type of function is provided for a vehicle having a function of continuing. There is.

  In order to achieve the above object, the solution means of the present invention is such that when the driver performs an internal combustion engine stop instruction operation (such as an ignition switch OFF operation), the internal combustion engine is driven for a predetermined period. The vehicle control device is provided with stop delay control means for executing “internal combustion engine stop delay control” for continuing the operation only and then stopping the internal combustion engine. Drive wheel rotation propriety judging means for judging whether or not the driving wheel can be rotated by the driving force transmitted from the internal combustion engine being transmitted to the vehicle control device, and the driving wheel rotation feasibility judging means. When it is determined that rotation is possible, stop delay control prohibiting means for prohibiting “internal combustion engine stop delay control” by the stop delay control means is provided.

  When it is determined by this specific matter that the drive wheel cannot be rotated by the drive wheel rotation availability determination means when the driver performs an internal combustion engine stop instruction operation such as an ignition switch OFF operation by the driver (for example, When the range position is set to “parking range position” and “neutral range position”, “internal combustion engine stop delay control” by the stop delay control means is executed. That is, the driving of the internal combustion engine is continued for a predetermined period, and then the internal combustion engine is stopped.

  On the other hand, when the driving wheel rotation enable / disable determining unit determines that the driving wheel can be rotated at the time when the internal combustion engine stop instruction operation is performed (for example, the range position is “parking range position” and “neutral position”). When it is not one of the “range positions” (for example, in the case of a drive position or a reverse position), that is, when the driving force of the internal combustion engine may be transmitted to the driving wheels, etc., “the internal combustion engine stop delay” "Control" is prohibited, and the drive of the internal combustion engine is stopped substantially simultaneously with the timing when the internal combustion engine stop instruction operation is performed. For example, the ignition operation of the spark plug is stopped and the fuel injection operation of the injector is stopped. This avoids a situation where the internal combustion engine is driven in a state where the driving force of the internal combustion engine may be transmitted to the drive wheels.

  For this reason, the vehicle driver confirms whether or not the drive wheels can be rotated by the driving force from the internal combustion engine when releasing the brake pedal depression operation after performing the internal combustion engine stop instruction operation. There is no need to do it. For example, it is not necessary to confirm that the transmission range position is operated to the “parking range position” or the “neutral range position”. That is, no trouble (inadvertent movement of the vehicle) occurs even if the depression of the brake pedal is canceled without performing this confirmation. Therefore, according to the present solution, even if the vehicle has the “internal combustion engine stop delay control” function, it can be handled in the same manner as a vehicle that does not have the “internal combustion engine stop delay control” function. That is, it is possible to realize a vehicle that does not make the occupant aware of having the “internal combustion engine stop delay control” function, and it is possible to improve the practicality of this type of vehicle.

  Further, the engine is provided with a rotation speed changing means for executing “rotational speed increase control” for changing the rotation speed of the internal combustion engine in accordance with a load by the auxiliary machinery of the internal combustion engine, and when the internal combustion engine stop instruction operation is performed. When the “rotational speed increase control” by the rotational speed changing means is being executed, the “rotational speed increase control” is prohibited when starting the “internal combustion engine stop delay control” by the stop delay control means. Rotational speed increase control prohibiting means is provided.

  More specifically, when the auxiliary machinery of the internal combustion engine is activated, the rotational speed changing means turns on the activation flag of the auxiliary machinery and executes “rotational speed increase control”. Then, when the rotation speed increase control prohibiting means starts the “internal combustion engine stop delay control”, the start flag of the auxiliary equipment that is ON is forcibly turned OFF.

  For example, when auxiliary equipment such as an air conditioner is used in an idling operation state of an internal combustion engine, generally, the idling rotational speed is set to a high value so that the driving force of the auxiliary equipment is appropriately obtained. This so-called idle up control is performed. That is, the idling speed is set higher by increasing the intake air amount and fuel injection amount of the engine. In such a situation, the engine ECU stores the air conditioner operation flag as “NO (air conditioner driving state)” by receiving the air conditioner start signal from the air conditioner ECU in the past. Conventionally, when the ignition switch is turned off from this state, the air conditioner is stopped. However, since the communication between the engine ECU and the air conditioner ECU is cut off, the engine ECU sets the air conditioner operation flag. The state continues to be stored as “ON”. That is, the idle-up control is continued even though the engine load by the air conditioner is lost. As a result, the engine speed suddenly increases immediately after the ignition switch is turned off, giving the passenger a sense of incongruity and deteriorating the fuel consumption rate. In addition, as auxiliary machines which cause such a situation, not only an air conditioner but lamps, such as a headlamp, and various things, such as an acoustic (audio) apparatus, are mentioned.

  In order to avoid such a situation, in the present solution, when the internal combustion engine stop instruction operation is performed, the starting flag of the auxiliary machinery that is turned on is forcibly turned off. That is, “rotational speed increase control” is canceled substantially simultaneously with the stop of the auxiliary machinery. For this reason, a phenomenon such as a sudden increase in the rotational speed is not caused, and even if the vehicle has an “internal combustion engine stop delay control” function, the passenger is informed that it has this “internal combustion engine stop delay control” function. A vehicle that is not conscious can be realized, and the practicality of this type of vehicle can be enhanced.

  Further, the drive wheel rotation propriety determining means is such that the range position of the transmission to which the driving force from the internal combustion engine can be transmitted is “advance range position (D range, etc.)” or “reverse range position (R range)”. In addition, the drive wheel is determined to be capable of rotating.

  Further, the drive wheel rotation availability determination means is configured to determine that the drive wheel cannot be rotated when the braking force applied to the drive wheel is equal to or greater than a predetermined value.

  Further, when the driving wheel rotation enable / disable determining unit determines that the driving wheel can be rotated when the internal combustion engine stop instruction operation is performed, the driving wheel is driven by the driving force from the internal combustion engine. Drive wheel non-rotating means for making rotation impossible is provided.

  The drive wheel non-rotating means here means that the range position is set to “parking range position” or “neutral range position” when the transmission range position is neither “parking range position” nor “neutral range position”. It is possible to change the braking force, or to increase the braking force (braking force) on the drive wheels.

  In the present invention, the driving force from the internal combustion engine is applied to a vehicle having a function of continuing to drive the internal combustion engine for a predetermined period even when the stop instruction operation of the internal combustion engine is performed because the ignition switch is turned off. If the drive wheel is transmitted and can rotate, the "internal combustion engine stop delay control" is prohibited, for example, so as not to cause a problem due to the provision of the "internal combustion engine stop delay control" function. Thus, it is possible to realize a vehicle that does not make the occupant aware of having this type of function, and it is possible to improve the practicality of this type of vehicle.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, the case where the present invention is applied to an automobile equipped with an in-cylinder direct injection multi-cylinder (for example, four-cylinder) gasoline engine will be described.

(First embodiment)
-Outline configuration of engine-
FIG. 1 shows a schematic configuration of an engine (internal combustion engine) 1 mounted on an automobile according to the present embodiment. As shown in FIG. 1, this engine 1 is a spark ignition type reciprocating engine 1, and fuel is directly injected into a combustion chamber 12 of a cylinder 11 by an in-cylinder direct injection type injector (fuel injection valve) 2 and mixed. Qi is supposed to generate. A piston 3 is accommodated in each cylinder 11 of the engine 1, and the piston 3 reciprocates in the cylinder 11 as the air-fuel mixture burns. The injector 2 is connected to a delivery pipe 21 as a fuel pressure accumulating container, and fuel is supplied from the delivery pipe 21. The fuel directly injected into the combustion chamber 12 by the injector 2 generates an air-fuel mixture together with the air A introduced into the combustion chamber 12 through the intake manifold 41 constituting a part of the intake passage.

  During the idling operation of the engine 1, the amount of fuel determined by the injector valve opening period correction operation is injected into the cylinder 11 from the injector 2, while when the vehicle is traveling, the load KL of the engine 1 and the engine speed NE are set. Fuel is injected from the injector 2 at a corresponding timing and at a necessary amount. The fuel injected from the injector 2 into the combustion chamber 12 generates an air-fuel mixture with the air A introduced into the cylinder 11 as the intake valve 42 opens, and is ignited by the spark plug 5 and burned. The combustion pressure of the air-fuel mixture is transmitted to the piston 3 and causes the piston 3 to reciprocate. The intake valve 42 is driven by an intake camshaft 43. The intake camshaft 43 is rotationally driven by the power extracted from the crankshaft 6 being transmitted by a timing belt or the like.

  The reciprocating motion of the piston 3 is transmitted to the crankshaft 6 via the connecting rod 31, where it is converted into rotational motion and taken out as the output of the engine 1. The air-fuel mixture after combustion becomes exhaust gas Ex and is discharged to the exhaust manifold 71 which is a part of the exhaust passage as the exhaust valve 72 is opened. The exhaust gas Ex is purified by a catalytic converter 74 provided on the downstream side of the exhaust manifold 71 and then released into the atmosphere. The exhaust valve 72 is driven by an exhaust camshaft 73. The exhaust camshaft 73 is rotationally driven by the power extracted from the crankshaft 6 being transmitted by a timing belt or the like.

  Further, the intake air amount of the engine 1 is adjusted by a throttle body 44 provided on the downstream side of the air cleaner 45 in the intake passage 4. The throttle body 44 includes a throttle valve 44a formed of a butterfly valve, a throttle motor 44b that opens and closes the throttle valve 44a, and a throttle opening sensor 44c that detects the opening of the throttle valve 44a. An engine ECU 8 to be described later acquires an output from an accelerator opening sensor 82 that detects an accelerator opening operated by a driver, sends a control signal to the throttle motor 44b, and a throttle valve 44a from the throttle opening sensor 44c. The throttle valve 44a is controlled to an appropriate opening degree based on the feedback signal of the opening degree. As a result, the amount of air A introduced into the cylinder 11 of the engine 1 is controlled.

-Description of control block-
The engine 1 is attached with sensors for acquiring information relating to operation and information relating to control of the engine 1 in order to control the operation. The sensors include a crank angle sensor 81 used for detecting the engine speed, the accelerator opening sensor 82, an air flow sensor 83 for detecting the intake air amount, an intake air temperature sensor 84 for detecting the intake air temperature, and a water jacket. There are sensors such as a cooling water temperature sensor 85 for detecting the cooling water temperature in the inside and an O ₂ sensor 86 for detecting the oxygen concentration in the exhaust gas Ex. An engine ECU (Electronic Control Unit) 8 that controls the operation of the engine 1 acquires outputs from these sensors and controls the operation of the engine 1.

  FIG. 2 is a block diagram showing this control system. As shown in this figure, the engine control system includes the engine ECU 8 for controlling the operating state of the engine 1. The engine ECU 8 includes a CPU (Central Processing Unit) 8A, a ROM (Read Only Memory) 8B, a RAM (Random Access Memory) 8C, a backup RAM 8D, and the like.

  The ROM 8B stores various control programs, maps that are referred to when the various control programs are executed, and the like. The CPU 8A executes arithmetic processing based on various control programs and maps stored in the ROM 8B.

  The RAM 8C is a memory that temporarily stores calculation results in the CPU 8A, data input from each sensor, and the backup RAM 8D is a non-volatile memory that stores data to be saved when the engine 1 is stopped. The CPU 8A, ROM 8B, RAM 8C, and backup RAM 8D are connected to each other via the bus 8G, and are connected to the external input circuit 8E and the external output circuit 8F.

In addition to the throttle opening sensor 44c, the crank angle sensor 81, the accelerator opening sensor 82, the air flow sensor 83, the intake air temperature sensor 84, the cooling water temperature sensor 85, and the O ₂ sensor 86, the external input circuit 8E includes intake pressure. Detects an intake pressure sensor 87, a fuel pressure sensor 88 that detects fuel pressure in the delivery pipe 21, a cam angle sensor 89 for cylinder discrimination, and a range position of an automatic transmission (not shown) (operating position of a shift lever operated by a driver). A shift position sensor (drive wheel rotation availability determination means) 80 and the like are also connected.

  On the other hand, the external output circuit 8F includes an electromagnetic spill that controls the fuel discharge amount of the fuel pump P (see FIG. 3) including the injector 2, the throttle motor 44b, the igniter 51 that determines the ignition timing of the spark plug 5, and the electric pump. A valve 22 or the like is connected.

  The engine ECU 8 calculates the final fuel injection amount used to control the amount of fuel injected from the injector 2 based on the engine speed, the load factor, and the like when the automobile is running.

  Here, the engine speed is obtained from the detection signal of the crank angle sensor 81. The load factor is a value indicating the current load ratio with respect to the maximum engine load of the engine 1, and is calculated from a parameter corresponding to the intake air amount of the engine 1 and the engine speed NE.

  Then, the engine ECU 8 drives and controls the injector 2 based on the final fuel injection amount calculated by calculation, and controls the amount of fuel injected from the injector 2. Since the amount of fuel injected from the injector 2 (fuel injection amount) is determined by the fuel pressure (fuel pressure) in the delivery pipe 21 and the fuel injection time, the fuel pressure is set to an appropriate value in order to make the fuel injection amount appropriate. Need to be maintained. In order to achieve this, the engine ECU 8 feedback-controls the fuel discharge amount of the fuel pump P so that the actual fuel pressure obtained from the detection signal of the fuel pressure sensor 88 approaches the target fuel pressure set according to the engine operating state. To maintain the fuel pressure at an appropriate value. The fuel discharge amount of the fuel pump P is feedback controlled by adjusting the valve closing period (valve closing start timing) of the electromagnetic spill valve 22.

  Further, the engine 1 in the present embodiment can also perform idle-up control by the engine ECU 8. This idle-up control is performed by, for example, idling rotation by increasing the intake air amount and the fuel injection amount compared to the normal idling operation when auxiliary equipment such as an air conditioner is used during idling operation of the engine 1. This is control for setting the number to a high value and properly obtaining the driving force of the auxiliary devices ("rotational speed increase control" by the rotational speed changing means).

  For example, when an air conditioner is activated by, for example, an occupant of an automobile turning on an air conditioner switch on a console panel, an air conditioner activation signal is transmitted from the air conditioner ECU 9 (see FIG. 3) to the engine ECU 8. Then, the engine ECU 8 stores the air conditioner operation flag (start flag) as “ON (air conditioner driving state)” by receiving this air conditioner start signal. This air conditioner operation flag is kept “ON” until an air conditioner stop signal is transmitted from the air conditioner ECU 9 to the engine ECU 8. That is, the air conditioner operation flag is switched from “ON” to “OFF” when the vehicle occupant turns off the air conditioner switch.

  The engine ECU 8 according to this embodiment, when stopping the engine 1, “stops the internal combustion engine stop delay” as stop control for operating the ignition operation of the spark plug 5 and the fuel injection operation of the injector 2 for a predetermined period after the ignition switch is turned off. Control "(" internal combustion engine stop delay control "executed by the stop delay control means). Details of the “internal combustion engine stop delay control” will be described later.

-Description of control circuit-
FIG. 3 is a circuit diagram showing an outline of a control system for controlling the engine 1. The control circuit includes an ignition switch 110, a main relay 120, an ignition / injection relay 130, an ignition device 50, an injection device 20, a pump drive relay 140, a fuel pump P, the engine ECU 8, and a power line. PL and a ground line SL are provided.

  Power supply line PL is connected to the positive terminal of a battery (not shown), and ground line SL is connected to the negative terminal of the battery.

  The ignition switch 110 is disposed between the power supply line PL and the engine ECU 8, and is operated by a driver (driver) of the automobile.

  Main relay 120 is arranged between power supply line PL and engine ECU 8, and supplies / cuts off electric power from power supply line PL to engine ECU8. The main relay 120 includes a contact 122 and a coil 124. When a current flows through the coil 124, the main relay 120 performs an on / off operation of the contact 122 using a magnetic force generated in the coil 124. That is, in the main relay 120, the contact 122 is turned on when a current is passed through the coil 124, and the contact 122 is turned off when a current is not passed through the coil 124.

  Ignition / injection relay 130 is disposed between power supply line PL and ignition device 50 and injection device 20, and supplies / cuts off power from power supply line PL to ignition device 50 and injection device 20. The ignition / injection relay 130 includes a contact 132 and a coil 134. When a current flows through the coil 134, the ignition / injection relay 130 performs an on / off operation of the contact 132 using a magnetic force generated in the coil 134. Coil 134 has one end connected to a line connecting contact 122 of main relay 120 to engine ECU 8, and the other end connected to ground node 150.

  The ignition / injection relay 130 is driven by the output from the main relay 120. That is, when the main relay 120 is turned on, a current flows from the main relay 120 to the coil 134 of the ignition / injection relay 130 and the ignition / injection relay 130 is turned on. Further, when the main relay 120 is turned off, no current flows from the main relay 120 to the coil 134, so the ignition / injection relay 130 is turned off.

  The ignition device 50 is supplied with operating power from the power line PL via the ignition / injection relay 130. The ignition device 50 includes the igniter 51 and the spark plug 5. Igniter 51 operates based on a control command from engine ECU 8, and boosts the voltage received from power supply line PL via ignition / injection relay 130. The spark plug 5 generates a discharge spark for igniting the air-fuel mixture using the boosted voltage boosted by the igniter 51.

  The injection device 20 is supplied with operating power from the power supply line PL via the ignition / injection relay 130. The injector 20 includes the injectors 2, 2,... For the cylinders of the engine 1. Each of the injectors 2, 2,... Operates based on a control command from the engine ECU 8, and injects fuel supplied from the fuel pump P into fine particles.

  The pump drive relay 140 is disposed between the ignition switch 110 and the fuel pump P, and supplies / cuts off electric power from the power supply line PL to the fuel pump P. The pump drive relay 140 includes a contact 142 and a coil 144, and when the current flows through the coil 144, the pump 142 is turned on / off using the magnetic force generated in the coil 144. The coil 144 has one end connected to the ignition switch 110 and the other end connected to the engine ECU 8.

  The pump drive relay 140 is operable when the ignition switch 110 is turned on, and is driven by the engine ECU 8. When the ignition switch 110 is turned off, the pump drive relay 140 is also turned off in synchronization therewith.

  Fuel pump P, which is an electric pump, receives supply of operating power from power supply line PL via ignition switch 110 and pump drive relay 140 connected in series. Then, when the pump drive relay 140 is turned on based on the operation command from the engine ECU 8, the fuel pump P operates by receiving power supply from the pump drive relay 140, and sends the fuel in the fuel tank to the injection device 20. Supply.

-Internal combustion engine stop delay control-
In the present embodiment, the engine ECU 8 is configured such that the ignition switch 110 is turned off by the driver of the automobile in addition to the above-described opening degree control of the throttle valve 44a, fuel injection amount control of the injector 2, ignition timing control of the spark plug 5, and the like. Then, “internal combustion engine stop delay control” can be executed on the engine 1. In this “internal combustion engine stop delay control”, an actuator (such as intake and exhaust valves 42 and 72 controlled by VVT (Variable Valve Timing)) that operates in accordance with the hydraulic pressure of the working hydraulic system of the engine 1 is used for the next engine start. Is a control operation for setting the engine 1 to a predetermined position, and the engine 1 is continuously driven for a predetermined period (for example, about 2 to 3 seconds) even after the ignition switch 110 is turned off.

  That is, when the ignition switch 110 is turned off, the engine ECU 8 continues to drive the ignition device 50 and the injection device 20 for a predetermined time. Then, after a predetermined time has elapsed, the engine ECU 8 stops the ignition device 50 and the injection device 20, and stops power feeding to the coil 124 of the main relay 120. Thereby, main relay 120 is turned off, and power feeding from power supply line PL to engine ECU 8 is interrupted. That is, engine ECU 8 cuts off power supply from power supply line PL.

  As a feature of this embodiment, in the “internal combustion engine stop delay control”, the execution state is changed according to the state of the automobile. Specifically, the execution state of “internal combustion engine stop delay control” is changed in accordance with the operation position of the shift lever and the driving state of auxiliary equipment such as an air conditioner.

  More specifically, when the ignition switch 110 is turned off, the transmission range position detected by the shift position sensor 80 is “P (parking range position)” or “N (neutral range position)”. For example, “D (drive range position)”, “R (reverse range position)”, “1 (first speed range position)”, “2 (second speed range position)”, etc. When the internal combustion engine stop delay control is prohibited, the ignition device 50 and the injection device 20 are stopped almost simultaneously with the ignition switch 110 being turned off to stop the engine 1 (stop). (Inhibiting operation of “internal combustion engine stop delay control” by the delay control prohibiting means).

  Further, when the above-described idle-up control of the engine 1 is being executed when the ignition switch 110 is turned off, an electric load flag (for example, the above-described air conditioner operation flag) on the engine ECU 8 is forcibly set to “OFF”. As a result, the idling-up control is canceled (rotational speed increase control is prohibited by the rotational speed increase control prohibiting means), and then the “internal combustion engine stop delay control” is permitted. Hereinafter, a specific control procedure will be described.

  FIG. 4 is a flowchart showing a procedure of “internal combustion engine stop delay control” executed by the engine ECU 8. The internal combustion engine stop delay control routine shown in this flowchart is executed at a predetermined cycle.

  First, in step ST1, it is determined whether or not the ignition switch 110 is turned off (IGSW = OFF) based on the potential of the connection line with the ignition switch 110. If it is determined that the ignition switch 110 is not turned off (No in step ST1), the counter C provided in advance in the engine ECU 8 is reset to “0” (step ST2). This counter C is a counter for measuring the execution duration time of the “internal combustion engine stop delay control”. Then, when the counter C is reset to “0”, the process proceeds to step ST3, and the above ignition control by the normal ignition device 50 and the fuel injection control by the injection device 20 are continued, and this routine is finished.

  On the other hand, if the ignition switch 110 is turned off and the determination in step ST1 is Yes, the process proceeds to step ST4, where “1” is added to the counter C and the time from when the ignition switch 110 is turned off is increased. Keep time. At this time, the fuel pump P stops when the ignition switch 110 is turned off. In addition, driving of auxiliary equipment such as an air conditioner is also stopped.

  Thereafter, the process proceeds to step ST5, in which whether or not the transmission range position detected by the shift position sensor 80 is set to either "P (parking range position)" or "N (neutral range position)". judge. That is, it is determined whether or not the driving force of the engine 1 is not transmitted to the driving wheels.

  The transmission range position is set to “P” or “N”, and if “Yes” is determined in step ST5, the process proceeds to step ST6, while the transmission range position is any of “P” and “N”. If not, the determination in step ST5 is No, and the process proceeds to step ST9.

  In step ST9, the ignition device 50 and the injection device 20 are stopped (ignition cut / fuel injection cut) to stop the engine 1. That is, the “internal combustion engine stop delay control” is prohibited, and the engine 1 is stopped substantially simultaneously with the ignition switch 110 being turned off. That is, the execution of “internal combustion engine stop delay control” in a state where the driving force of the engine 1 can be transmitted to the driving wheels is prohibited.

  On the other hand, in step ST6, in order to prevent the output fluctuation of the engine 1 due to the operation of the accelerator pedal, the update of the accelerator opening signal received from the accelerator opening sensor 82 is prohibited, and the throttle valve 44a is controlled regardless of the depression amount of the accelerator pedal. The degree of opening of the throttle valve 44a is controlled so that the degree of opening becomes constant. That is, the output fluctuation of the engine 1 due to depression of the accelerator pedal during the “internal combustion engine stop delay control” of the engine 1 is prevented.

  Thereafter, the process proceeds to step ST7, and an electric load state flag (for example, an air conditioner operation flag) on the engine ECU 8 is forcibly set to “OFF”. As a result, the idle-up control is canceled, and the idle speed is set to the speed when there is no load (such as an electrical load) on the auxiliary equipment. That is, the intake air amount and the fuel injection amount are set to the normal idle rotation speed (the rotation speed when the idle up control is not performed).

  Next, in step ST8, it is determined whether or not the added counter C is equal to or greater than a value α corresponding to a predetermined time. If it is determined in step ST8 that the counter C is less than α (No determination in step ST8), the engine ECU 8 still executes a predetermined time ("internal combustion engine stop delay control") after the ignition switch 110 is turned off. It is determined that the time until the effect of (1) is obtained has not elapsed, and the ignition control by the ignition device 50 and the injection control by the injection device 20 are continued (continuation of the internal combustion engine stop delay control).

  On the other hand, if it is determined that the counter C is greater than or equal to α (Yes in step ST8), the output of the control command to the ignition device 50 and the injection device 20 is stopped, and the ignition control by the ignition device 50 and the injection device 20 are performed. The fuel injection control is stopped (ignition cut / fuel injection cut), and the “internal combustion engine stop delay control” is ended (step ST9). Thereafter, the engine ECU 8 turns off the main relay 120 to self-shut off, and ends a series of processes. When the main relay 120 is turned off, the ignition / injection relay 130 is also turned off as described above, and the power supply from the power line PL to the ignition device 50 and the injection device 20 is interrupted.

  In step ST6, instead of prohibiting updating of the accelerator opening signal received from the accelerator opening sensor 82, it is prohibited to take in the accelerator opening signal or to force the accelerator opening signal to have its minimum value. You may perform the process to set.

  As described above, according to the control device according to this embodiment, after the ignition switch 110 is turned off, the ignition by the driver is performed in the automobile in which “internal combustion engine stop delay control” for operating the engine 1 for a predetermined period is executed. If the transmission range position is set to either “P” or “N” when the switch 110 is turned off, the “internal combustion engine stop delay control” is executed. On the other hand, when the ignition switch 110 is turned off, if the transmission range position is not “P” or “N”, that is, the driving force of the engine 1 is transmitted to the driving wheels. If there is a possibility that the engine 1 will be stopped, the "internal combustion engine stop delay control" is prohibited and the drive of the engine 1 is immediately stopped (ignition cut / fuel injection cut). As a result, it is possible to avoid a situation in which the engine 1 is driven in a state where the driving force of the engine 1 may be transmitted to the drive wheels.

  Therefore, the driver does not need to confirm that the range position is operated to “P” or “N” when releasing the brake pedal depression operation after the ignition switch 110 is turned off. That is, no trouble (inadvertent movement of the vehicle) occurs even if the depression of the brake pedal is canceled without performing this confirmation. Therefore, even if the vehicle has an “internal combustion engine stop delay control” function, it can be handled in the same manner as an automobile that does not have this “internal combustion engine stop delay control” function. It is possible to realize a car that does not make the occupant aware that it is equipped, and to increase the practicality of this type of car.

  In the present embodiment, when the ignition switch 110 is turned off, the electric load state flag (such as an air conditioner operation flag) on the engine ECU 8 that is turned on is forcibly turned off. . That is, the idle-up control is also released almost simultaneously with the stop of the auxiliary equipment accompanying the turning-off operation of the ignition switch 110. For this reason, immediately after the ignition switch 110 is turned off, a phenomenon such as a sudden increase in the engine speed due to the loss of the engine load is not caused. Even if the automobile has the “internal combustion engine stop delay control” function, this “ It is possible to realize an automobile that does not make the occupant aware of having the “internal combustion engine stop delay control” function, and this can also increase the practicality of this type of automobile.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the present embodiment, the operation of “internal combustion engine stop delay control” executed by the engine ECU 8 is different from that in the first embodiment. In addition, since the configuration of the engine 1 and the basic drive operation of the engine 1 are the same as those of the first embodiment, only the operation of “internal combustion engine stop delay control” will be described here.

  FIG. 5 is a flowchart showing a procedure of “internal combustion engine stop delay control” executed by the engine ECU 8 in the present embodiment. The internal combustion engine stop delay control routine shown in this flowchart is executed at a predetermined cycle.

  In addition, the operations of steps ST1 to ST4 and steps ST6 to ST9 in FIG. 5 are the same as the operations of the same step numbers in the flowchart of FIG. 4 of the first embodiment described above, and thus the description thereof is omitted here.

  The ignition switch 110 is turned off (Yes in step ST1), and “1” is added to the counter C (step ST4). Then, the process proceeds to step ST11, where the transmission range position is set to “parking range position” or “neutral. Forcibly switched to “range position”. For example, by switching to the “parking range position”, the state in which the driving force of the engine 1 is transmitted to the driving wheel is eliminated (the driving wheel cannot be rotated by the driving wheel non-rotating means).

  In this switching operation, an actuator (range position changing means) that automatically operates the shift lever in the passenger compartment (the position of the shift lever is automatically changed) is provided, and the shift lever is automatically set to “parking range position” or It may be possible to operate to the “neutral range position” or to switch the gear inside the transmission to “parking state” or “neutral state” without providing this actuator, that is, without moving the shift lever. May be. In this case, at the end of the “internal combustion engine stop delay control”, the engine 1 is stopped with the shift lever in the “drive position”, for example. Generally, the engine 1 has the shift lever in the “parking range position”. Since the engine cannot be started unless it is set to the “neutral range position”, the driver will operate the shift lever to the “parking range position” or the “neutral range position” when the engine 1 is started next time.

  Subsequent control operations (control operations after step ST6) are the same as those in the first embodiment described above.

  Thus, in the present embodiment, there is no possibility that the transmission range position of the transmission is already in the “parking range position” or the “neutral range position” and the driving force of the engine 1 is transmitted to the drive wheels. In the state, the “internal combustion engine stop delay control” is started as it is, and the driving of the engine 1 is continued for a predetermined period. On the other hand, when the range position of the transmission is neither “parking range position” nor “neutral range position”, that is, when the driving force of the engine 1 may be transmitted to the driving wheels. Therefore, “internal combustion engine stop delay control” is started in a state where the range position of the transmission is forcibly switched to the “parking range position” or the “neutral range position”.

  For this reason, in any case, a situation in which the engine 1 is driven in a state where the driving force of the engine 1 may be transmitted to the drive wheels does not occur. Therefore, inadvertent movement of the vehicle due to the start of the “internal combustion engine stop delay control” does not occur, and a problem caused by the provision of the “internal combustion engine stop delay control” function does not occur. Thereby, also by this embodiment, the utility of this kind of car can be improved.

(Third embodiment)
Next, a third embodiment of the present invention will be described. This embodiment is also different from the first embodiment in the operation of “internal combustion engine stop delay control” executed by the engine ECU 8. In addition, since the configuration of the engine 1 and the basic drive operation of the engine 1 are the same as those of the first embodiment, only the operation of “internal combustion engine stop delay control” will be described here.

  FIG. 6 is a flowchart showing a procedure of “internal combustion engine stop delay control” executed by the engine ECU 8 in the present embodiment. The internal combustion engine stop delay control routine shown in this flowchart is executed at a predetermined cycle.

  In addition, the operations of steps ST1 to ST5 and steps ST6 to ST9 in FIG. 6 are the same as the operations of the same step numbers in the flowchart of FIG. 4 of the first embodiment described above, and thus description thereof is omitted here.

  In step ST5, if the transmission range position is not one of the “parking range position” and the “neutral range position”, the determination in step ST5 is No, the process proceeds to step ST12, and the drive wheels are stopped. Retained. For example, a brake actuator (brake holding means) (not shown) is actuated to increase the brake hydraulic pressure so that the brake pad is pressed against the brake disc and the drive wheels are braked. This prevents the vehicle from moving even when the driving force from the engine 1 is applied to the driving wheels (the driving wheels cannot be rotated by the driving wheel non-rotating means).

  The subsequent control operations in steps ST6 to ST9 are the same as those in the first embodiment described above.

  After the “internal combustion engine stop delay control” is completed and the ignition device 50 and the injection device 20 are stopped (ignition cut / fuel injection cut) in step ST9 to stop the engine 1, the process proceeds to step ST13. The brake holding state in step ST12 is released.

  Thus, in the present embodiment, there is no possibility that the transmission range position of the transmission is already in the “parking range position” or the “neutral range position” and the driving force of the engine 1 is transmitted to the drive wheels. In the state, the “internal combustion engine stop delay control” is started as it is, and the driving of the engine 1 is continued for a predetermined period. On the other hand, when the range position of the transmission is neither “parking range position” nor “neutral range position”, that is, when the driving force of the engine 1 may be transmitted to the driving wheels. The “internal combustion engine stop delay control” is started in a state where the vehicle is prohibited from moving by applying a brake to the drive wheel. For this reason, in any case, the engine 1 is driven in a state where the vehicle does not move. Therefore, inadvertent movement of the vehicle due to the “internal combustion engine stop delay control” does not occur, and there is no inconvenience caused by having the “internal combustion engine stop delay control” function. Thereby, also by this embodiment, the utility of this kind of car can be improved.

  In the present embodiment, the parking brake may be actuated as an operation for holding the drive wheels in a stopped state (the operation in step ST12).

-Other embodiments-
In each of the embodiments described above, the case where the present invention is applied to an automobile equipped with the in-cylinder direct injection four-cylinder gasoline engine 1 has been described. The present invention is not limited to this, and can also be applied to automobiles equipped with other types of gasoline engines and diesel engines. Further, the number of cylinders and the engine type (V type, horizontally opposed type, etc.) are not particularly limited.

  In addition, the present invention is not limited to executing the internal combustion engine stop delay control only at the “parking range position” and the “neutral range position”. If the start flag of the auxiliary machinery is forcibly turned off, the “parking range position” Further, even if the internal combustion engine stop delay control is executed at a position other than the “neutral range position”, the driving force from the engine 1 can be suppressed, so that the effect of the present invention can be obtained. Are also included in the concept of the invention.

  Further, in the engine 1 according to each of the above embodiments, in the “internal combustion engine stop delay control”, both the ignition control by the ignition device 50 and the injection control by the injection device 20 are continued. May be continued. For example, if only the ignition control by the ignition device 50 is continued, the residual gas in the cylinder 11 is combusted, and the air-fuel mixture does not remain in the cylinder 11 after the engine is stopped, improving the engine startability and the exhaust properties. It is also possible to prevent the deterioration.

  Further, the transmission mounted on the automobile to which the present invention is applied is not limited to a general automatic transmission provided with a planetary gear mechanism. For example, an automobile equipped with an automatic manual transmission (AMT) that is configured by a parallel gear transmission similar to a general manual transmission and that automatically performs a shifting operation (gear stage switching operation) by a shift actuator, a select actuator, or the like. However, the present invention is also applicable. In particular, in the case of the second embodiment, if the parallel gear transmission is not in the neutral state when the ignition switch 110 is turned off, the shift actuator and the select actuator are operated to force It will be switched to the neutral state.

It is a figure which shows schematic structure of the engine mounted in the motor vehicle which concerns on embodiment. It is a block diagram which shows the control system of an engine. It is a circuit diagram of an engine control system. It is a flowchart figure which shows the procedure of the "internal combustion engine stop delay control" in 1st Embodiment. It is a flowchart figure which shows the procedure of the "internal combustion engine stop delay control" in 2nd Embodiment. It is a flowchart figure which shows the procedure of the "internal combustion engine stop delay control" in 3rd Embodiment.

Explanation of symbols

1 engine (internal combustion engine)
8 Engine ECU
9 Air conditioner ECU
20 injection device 50 ignition device 80 shift position sensor (range position recognition means)
110 Ignition switch

Claims (6)

Provided with a stop delay control means for executing “internal combustion engine stop delay control” for stopping the internal combustion engine after the driving of the internal combustion engine is continued for a predetermined period when the driver performs an instruction to stop the internal combustion engine. In the vehicle control device,
Driving wheel rotation availability determination means for determining whether or not the driving wheel is rotatable by transmission of the driving force from the internal combustion engine;
And a stop delay control prohibiting means for prohibiting the “internal combustion engine stop delay control” by the stop delay control means when the drive wheel rotation enable / disable determining means determines that the drive wheel can be rotated. The vehicle control apparatus characterized by the above-mentioned. In the vehicle control device according to claim 1,
Comprising a rotation speed changing means for executing "rotational speed increase control" for changing the rotation speed of the internal combustion engine in accordance with a load by the auxiliary machinery of the internal combustion engine;
At the time when the internal combustion engine stop instruction operation is performed, when the “rotational speed increase control” by the rotational speed changing means is being executed, the “internal combustion engine stop delay control” by the stop delay control means is started. In this case, the vehicle control apparatus includes a rotation speed increase control prohibiting unit that prohibits the “rotational speed increase control”. In the vehicle control device according to claim 2,
The above-mentioned rotation speed changing means turns on the startup flag of the auxiliary equipment when starting the auxiliary equipment of the internal combustion engine, and executes "rotational speed increase control".
The speed increase control prohibiting means forcibly turns off the start-up flag of the auxiliary machinery that is ON when starting the "internal combustion engine stop delay control". Control device. In the vehicle control device according to claim 1, 2, or 3,
The drive wheel rotation propriety judging means is capable of rotating the drive wheel when the range range of the transmission to which the driving force from the internal combustion engine can be transmitted is the “advance range position” or the “reverse range position”. A vehicle control device characterized by determining. In the vehicle control device according to any one of claims 1 to 4,
The drive wheel rotation availability determination means determines that the drive wheel cannot be rotated when the braking force applied to the drive wheel is greater than or equal to a predetermined value. In the vehicle control device according to any one of claims 1 to 5,
At the time when the internal combustion engine stop instruction operation is performed, if the drive wheel rotation availability determination means determines that the drive wheel can be rotated, the drive wheel is rotated by the drive force from the internal combustion engine. A vehicle control device comprising drive wheel non-rotating means for disabling.

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