JP2000337238A - Control system for spark-ignition type multiple cylinder engine, and driving device for vehicle with this engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a mixture in a plurality of cylinders from being exhausted in the unburnt state by stopping the output of ignition signals after all the ignition signals corresponding to the respective cylinders injected with fuel immediately before the stop of fuel injection are outputted after the stop of fuel injection when an engine is stopped. SOLUTION: In a device for automatically stopping an engine by an engine stop command during driving of a hybrid vehicle, an ECU 13 obtains conditions for materializing fuel cut-off by operation on the basis of detection signals of vehicle speed, engine speed, throttle valve opening, cooling water temperature, and the like. In the case of the fuel cut-off conditions being materialized, a pertinent cylinder is set as a fuel cut-off object cylinder to carry out fuel injection stop processing. In the case of an engine stop request being made with an ignition switch on, it is so controlled to stop the output of ignition signals after all the ignition signals corresponding to the respective cylinders injected with fuel immediately before the stop of fuel injection are outputted after the stop of fuel injection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control system for a spark ignition type multi-cylinder engine, and more particularly to a fuel injection valve to which electric power is supplied from a battery via an ignition key or a relay, and a fuel injection valve in response to an operation command. The present invention relates to a control system for a spark ignition type multi-cylinder engine suitable for use in a vehicle including an ignition device connected to the battery and supplied with power via a controlled self-shutoff relay.

[0002]

2. Description of the Related Art Fuel injection valves and ignition coils are
It is configured so that power is supplied via an ignition key. Conventionally, as shown in FIG. 19, an ignition key connected in series between an ignition coil and a battery has been widely used. However, recently, a method has been adopted in which an ignition coil is connected to a battery via a self-shutoff relay. The self-shut-off relay is turned on in conjunction with the ignition key by the engine control unit. When the self-shut-off relay is turned off, the self-shutoff relay is turned off after performing a key-off process.

[0003] On the other hand, hybrid vehicles are attracting attention as vehicles that are clean and have a large mileage. For example, as described in Japanese Patent Application Laid-Open No. 9-65508, there is known a hybrid vehicle in which an electric generator of an engine is driven to generate electric power, and a driving motor is driven by the electric power to travel.

[0004]

In the conventional example shown in FIG. 19, when the ignition key is turned off, the air-fuel mixture of the cylinders to which fuel has been injected is not ignited, and the air-fuel mixture of these cylinders is not Exhausted as combustion.

In the system connected to a battery via a self-shut-off relay, when an ignition key is turned off or an engine stop request is issued as described above, the mixture of the cylinders to which fuel has been injected before that time is generated. The ignition is performed on the ignition key, but thereafter, while the ignition key is in the ON state, the ignition is performed even though there is no air-fuel mixture to be ignited, so that wasteful power is consumed. Furthermore, the speed of rotation change when the engine is stopped is large, and the energization time immediately before the engine is stopped becomes abnormally long.
A failure such as a disconnection of the ignition coil may occur.

[0006] When the engine stop request is issued while the ignition key is on, the engine may be stopped to cut the fuel at the time of idling stop or deceleration.

[0007] Such a fuel cut for idling stop, deceleration running, and the like is more effective when used in a hybrid vehicle.

In a conventional hybrid vehicle, the drive source is appropriately switched according to the running condition. For example, the engine is stopped at idle or low vehicle speed where the engine efficiency is low, and the engine and motor are driven by the engine and motor at the time of starting and accelerating. Control is performed such as selecting and using an operating point with less gas and good fuel efficiency. However, even in a hybrid vehicle, when an engine stop request is issued, the air-fuel mixture of a cylinder to which fuel has been injected is ignited, and thereafter, while the ignition key is on, Even though there is no air-fuel mixture to be ignited, wasteful power is consumed for performing ignition.

SUMMARY OF THE INVENTION An object of the present invention is to overcome this problem, to prevent a mixture of a plurality of cylinders from being discharged without combustion when the engine is stopped, to consume unnecessary ignition power, and to disconnect the ignition coil. The present invention provides a control system for a spark-ignition multi-cylinder engine, which does not have any problem.

[0010] Another object of the present invention is to provide a vehicle having a spark ignition type multi-cylinder engine, particularly a hybrid vehicle.
It is an object of the present invention to provide a vehicle drive device suitable for frequently performing idling stop or fuel cut such as deceleration while the ignition switch is on.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a fuel injection type multi-cylinder engine in which fuel injection into each cylinder and ignition of an air-fuel mixture in each cylinder are controlled by an operation command and an engine command. An engine control unit that controls based on an operation state, the engine control unit stops fuel injection to each of the cylinders based on the operation command, and then controls each cylinder by fuel injected immediately before the stop of the fuel injection. A characteristic of the control system of the spark ignition type multi-cylinder engine is to stop outputting the ignition signal after all the ignition signals corresponding to the respective air-fuel mixtures have been output.

Another feature of the present invention is to control fuel injection to each cylinder of the engine and spark ignition to each cylinder based on an operation command for the spark ignition type multi-cylinder engine and an operation state of the engine. An engine control unit that stops the fuel injection when a stop request is issued to the engine during rotation of the engine, wherein the engine control unit stops fuel injection to each of the cylinders according to the engine stop request. Therefore, in the control system of the spark ignition type multi-cylinder engine, the output of the ignition signal corresponding to the fuel injection to each of the cylinders is stopped after the elapse of a delay time corresponding to 1/2 or several revolutions of the engine. .

Another feature of the present invention includes a fuel injection control program and an ignition control program, and performs fuel injection to each cylinder of the engine and spark ignition to each cylinder of the engine based on an operation command and an operation state of the engine. An engine control unit for controlling, the engine control unit setting an injection completed flag for each fuel injection to each of the cylinders, and resetting the injection completed flag for each spark ignition corresponding to the fuel injection to each of the cylinders And a control system for a spark ignition type multi-cylinder engine.

Another feature of the present invention resides in a drive device for a vehicle provided with the control system for a spark ignition type multi-cylinder engine.

Further, according to an embodiment of the present invention, the operation command is to stop the engine by cutting off fuel while keeping an ignition key turned on. Further, the ignition device is connected to the battery via a self-shut-off relay controlled in response to an operation command and supplied with power.

By performing the processing of fuel injection and ignition timing control according to the method of the present invention, when the engine is stopped, the air-fuel mixture of the plurality of cylinders is not discharged without being burned. Further, when fuel cut such as idling stop or deceleration running is performed while the ignition switch is on, there is no trouble such as unnecessary consumption of ignition power or disconnection of the ignition coil.

Further, according to the present invention, in a vehicle having a spark ignition type multi-cylinder engine, in particular, in a hybrid vehicle, it is suitable to frequently perform idling stop or fuel cut during deceleration running with the ignition switch on. Accordingly, it is possible to provide a drive device for a vehicle having a spark ignition type multi-cylinder engine.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an overall configuration diagram of a hybrid vehicle drive device according to one embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a control unit, which controls the engine 2 and the motor 3 according to the driving state of the vehicle. A powder clutch 9 is provided between a crankshaft of the engine 2 and a rotation shaft of the motor 3. The engine 2 is a spark ignition type multi-cylinder engine. The motor 3 is a permanent magnet type synchronous motor in the present embodiment, and receives power supply from a battery 5 via an inverter 4. Further, the electric power generated by the motor 3 is charged to the battery 5 via the inverter 4 at a required voltage. A transmission mechanism 10 is provided between the rotation shaft of the motor 3 and the axle 8. A resolver 18 as a speed sensor is provided on a rotating shaft of the motor 3.

The control unit 1 includes an engine 2 and a motor 3 according to the driving state of the vehicle and the state of charge of the battery.
And other operations are controlled. When the vehicle is decelerated (regenerative braking), the electric power generated by the motor 3 and stored in the battery 5 is replaced with an engine or assists the engine when starting or accelerating or when power is insufficient where exhaust gas poses a problem. It is used to drive the motor 3 as a source.

The control unit 1 includes a general control unit 11, a motor control unit 12,
Engine control unit 13, battery control unit 14, brake control unit 1
5, a CVT control unit 16, a clutch control unit 17, and the like.

The general control unit 11 receives information such as an ignition switch, an accelerator, a brake, a vehicle speed, a battery voltage and the like, determines a driving mode of the vehicle based on the information, and sets a target torque or a driving command NMG. *, K *, VBs * and S * are calculated, the operation command NMG * is set to the motor control unit 12, the target torque K * is set to the engine control unit 13, and the voltage command VB is set.
s * is the battery control unit 14, opening and closing command S
* Is output to the clutch control unit 17 respectively.

The motor control unit 12 generates and outputs a PWM signal for controlling the inverter 4 based on the operation command NMG * and information on the rotation speed and current of the motor 3. The motor 3 operates as an electric motor when the operation command NMG * is +, and as a generator when the operation command NMG * is-. Further, the motor / generator 68 is similarly controlled in response to a request for starting the engine or a request for generating electricity.

The engine control unit 13 controls the fuel injection amount and the ignition timing based on the target torque K * and the engine speed N.

The clutch control unit 17 controls the electromagnetic clutch 9 connecting the engine 2 and the motor 3 based on the command S *.

Reference numeral 20 denotes a throttle valve assembly having an electronically controlled throttle valve 40 for controlling the amount of intake air, that is, a throttle body. The air cleaner 21 is provided at the inlet and the air is branched to the respective cylinders of the engine 2 at the outlet. Plural intake branch pipes 2 to supply
2 are connected. Reference numeral 23 denotes an electronically controlled fuel injection valve attached to the intake branch pipe 22, and reference numeral 24 denotes a hot-wire type air flow sensor (air flow sensor).

FIG. 2 shows a so-called MPI (multi-cylinder fuel injection) type four-cylinder engine as an example of the overall configuration of a vehicle engine control system to which the present invention is applied. In FIG. 2, for example, a vehicle AC generator 68 is mechanically connected to a crankshaft 66 of an engine 2 mounted on a vehicle such as an automobile via a pulley or a belt.
67 is a starter motor.

The electronically controlled throttle valve 40 is opened and closed in conjunction with a motor controlled by the engine control unit 13.

The fuel is supplied from the fuel tank 43 to the fuel pump 4.
The air is sucked and pressurized in 4, is regulated to a constant pressure by a pressure regulator 45, and is injected into the intake pipe from a fuel injection valve 23 provided in the intake pipe 22.

The air flow sensor 24 outputs a signal corresponding to the amount of intake air. Further, a pulse is output from the crank angle sensor 28 incorporated in the distributor 32 at every predetermined crank angle, and these outputs are
The crank angle and the engine speed are input to the engine control unit 13, and the basic pulse width T corresponding to the charging efficiency is calculated from the intake air amount and the engine speed.
Ask for P.

The throttle valve 40 is provided with a throttle sensor 41 for detecting the opening degree and the fully closed position of the throttle valve.
Further, a water temperature sensor 60 for detecting a cooling water temperature is attached to the engine 2.

The O2 sensor 46, which is an air-fuel ratio sensor, is mounted on the exhaust pipe 64 of the engine and outputs a signal corresponding to the oxygen concentration of the exhaust gas. This signal is input to the engine control unit 13, and each of the fuel injection valves 2 is controlled so that the gas mixture to the engine reaches the target A / F.
3. Adjust the width of the fuel injection pulse to 3.

Reference numeral 53 denotes an accelerator switch, 54 denotes a neutral switch of a gear, and 55 denotes a vehicle speed sensor. 30
Represents an igniter, 31 represents an ignition coil, and 33 represents a spark plug.

As shown in FIG. 3, the engine control unit 13 includes a central processing unit (CPU) 100, an RO
M101, RAM 102, backup RAM 111 whose contents are not cleared even if ignition key is turned off,
An electrically writable memory 112 (for example, P-RO
M, EEP-ROM, flash ROM, etc.), interrupt controller 104, timer 105, input processing circuit 1
06, and an output processing circuit 107, which are connected by a bus 108.

The input processing circuit 106 receives an input signal (for example, an operation command τNE * or a signal from a cooling water temperature sensor, a throttle opening sensor, or the like), removes a noise component from the signal, and converts the signal. A / D conversion and bus 1
08 to the central processing unit 110. The central processing unit 110 takes in the A / D conversion result, and
02 and the backup RAM 111 to execute the fuel injection control program 132, the ignition timing control program 134, and other predetermined control programs stored in a medium such as a ROM, thereby providing a function of performing each control. . At this time, based on information from the timer 105 and the input processing circuit 106, the interrupt controller 104
Interrupt processing is also performed in a timely manner by an interrupt instruction issued from the user.

The calculation result and the result of the A / D conversion are temporarily stored in a RAM, and the calculation result is output as a control output signal through an output circuit, and the fuel injection valves 23 (A to D), Igniter 30, ETC motor 4
It is used for control such as 0.

The hybrid vehicle drive device of the present invention is driven based on a predetermined operation mode. That is, the general control unit 11 selects one of a plurality of preset operation modes based on the driving state of the vehicle, for example, the accelerator opening, the vehicle speed, the battery state, and the like,
The driving conditions such as the target torque and the vehicle speed of the vehicle are determined according to each driving mode, and the optimal driving source is selected from the viewpoint of reducing the exhaust gas such as HC and improving the fuel efficiency. The target torque to be output by the drive device of the vehicle is obtained, for example, by calculation.

The driving modes include, for example, the following, which are for turning on the accelerator and clutch of the vehicle,
Either one is selected according to OFF or the like.

Warm-up operation mode: The water temperature is low (for example, 70 ° C. or less), the clutch is off, the key switch is on,
When the accelerator switch is off, the engine is idled.

Motor running mode: When the charging rate of the battery exceeds a predetermined value and the accelerator opening is not large, the vehicle runs only with the driving force of the motor (power running mode). The key switch is on, the accelerator switch is off, the brake switch is on, and the vehicle speed is 0.
If it is larger and the charging rate of the battery has not reached the predetermined value, the motor is used as a generator and the vehicle is decelerated while charging the battery (regeneration mode).

Engine running power generation mode: When the charging rate of the battery has not reached a predetermined value, the motor is used as a generator to run while charging the battery. As a motor operation command, a torque equivalent value for driving the motor is added to an engine rotational speed equivalent value corresponding to the accelerator opening and output.

Engine stop mode (idle stop): When a key switch is turned on, an accelerator switch is turned off, and a clutch is turned off, the engine is stopped.

Next, FIG. 4 shows an example of a power supply circuit of the fuel injection valve 23 and the ignition coil 27. Electric power is supplied from the battery 5 to the fuel injection valve 23 via an ignition key 27. On the other hand, the ignition coil 27, the air flow meter 24, and the crank angle sensor 28 are connected to the battery 5 via a self-shut-off relay 26. I have. Self shut-off relay 2
6 is controlled on and off by the engine control unit 13 in conjunction with the ignition key 27.

Next, FIG. 5 shows a configuration example of the motor control unit 12. Motor control unit 1
2 is an idiq detecting means 124, an id, an iq current controlling means 125, a 2/3 phase converting means 121, a PWM controlling means 1
22 and a phase calculation means 120 and a speed calculation means 123. The speed calculating means 123 is connected to the encoder 18A of the resolver 18, and the phase calculating means 120 is connected to the magnetic pole position detecting means 18B of the resolver 18. Further, the motor control unit 12 includes a torque command generation unit 128, an Iq control unit 127, and an Id control unit 12.
6 is provided.

The torque command generator 128 generates a target torque command τM * based on the command NM reflecting the accelerator opening and the like by the driver's operation and the motor speed calculated by the speed calculator 123.

In the motor control unit 12, the torque command calculator 128 calculates a torque command value τMG * based on the rotation speed calculated by the speed calculator 123 from the driving finger NMG * and the pulse signal from the encoder 18A. . Command value Iq * of q-axis current corresponding to torque current
Is calculated by the Iq control means 127 for calculating based on the torque command value τMG *. On the other hand, the d-axis current command value Id
For *, the Id control unit 126 calculates Id * that minimizes the loss based on the torque command value τMG * and the rotation speed calculated by the speed calculation unit 123. In this way, the motor control unit 12 calculates the current command values Iq * and Id * necessary for high-efficiency control of the motor 3.

The IdIq detection means 124 is provided by the current detector 1
7 for the three-phase AC current of the motor current
Two-phase coordinate conversion is performed to process and calculate d- and q-axis currents Id and Iq. Based on these detected values and the command values Iq * and Id *, the IdIq current control means 125 performs a proportional or proportional-integral current control process to calculate voltage command values Vq * and Vd *.

Further, the 2 / 3-phase conversion means 121 performs a 2-phase / 3-phase coordinate conversion to obtain a 3-phase AC voltage command value V
U *, VV *, VW * are calculated. PWM control means 122
Compares the voltage command values VU *, VV *, VW * with the carrier signal of the triangular wave signal,
The WM signal is generated, and the inverter 4 is driven. By applying the PWM-controlled voltage to the motor 3 in this manner, the current of the motor 3 is controlled to the current command values Iq *, Id *.

The 2/3 phase conversion processing 121, IdIq
The phase angles θ1,
θ2 is a magnetic pole position detector 18B that outputs a signal having the same phase as the induced voltage of the motor 3 in the phase calculation means 120;
Encoder 18 that outputs a rotation angle signal (pulse signal)
Calculated from each output of A. By performing such processing, the motor 3 is controlled with the torque of the torque command value τM * and with high efficiency with minimum loss.

FIGS. 6 to 9 show one embodiment of the processing flow in the engine control unit of the present invention.

First, FIG. 6 shows a fuel injection control program 1
32 shows a processing flow of fuel injection control by No. 32. At first,
A basic pulse TP is calculated from the intake air amount QA and the engine speed N (S501). Further, a water temperature correction and a humidity correction are added to the basic pulse TP to calculate an intermediate parameter (S502). On the other hand, from the vehicle speed VSP, the engine speed N, the throttle valve opening TVO, and the cooling water temperature TW, a condition for establishing a fuel cut during normal operation is calculated (S503). Further, a condition for satisfying the fuel cut at the time of high speed rotation is obtained from the engine speed N (S50).
4). Further, in addition to the vehicle speed VSP, the throttle valve opening TVO, the cooling water temperature TW, and the like, the state of the air conditioner switch and the like are used to control the operation of the fuel cut during the idle stop condition (S
505). Then, a cylinder corresponding to any of these fuel cut conditions is set as a fuel cut target cylinder (S506).

Then, distribution processing is performed on the cylinders that are not targeted for fuel cut (S507), the injection pulse width is calculated (S508), and the injection output processing is performed while the accelerator is on (S509).

In the injection output processing, as shown in FIG. 7, an injection completed flag is set for a cylinder to which fuel has been injected, and then it is confirmed by an ignition signal that ignition has been performed in that cylinder. , A process of clearing this flag. When performing a fuel cut, the injection completed flag is not set. The information of these injection completion flags is used for the next ignition timing control process.

FIG. 8 shows a processing flow of the ignition timing control by the ignition timing control program 134. First, an ignition timing is calculated from the engine speed N and the cooling water temperature TW according to the operating conditions of the engine at normal times (601). On the other hand, the ignition timing and dwell angle at the start are calculated from the engine speed N and the battery voltage VB (602, 60).
5). Further, a switching process for smooth switching between the ignition timing at the normal time and the ignition timing at the start is performed (60).
3), calculate the ignition timing (604). Further, the non-energization angle is calculated from the dwell angle (606). Finally, an ignition output process is performed based on the calculated ignition timing and de-energization angle and information on the flag indicating that the injection has been completed (607).

In the ignition output process, as shown in FIG. 9, an interrupt process is performed based on a predetermined crank angle signal (REF), and the counter starts counting down. Then, when the count value becomes 0, it is checked whether or not the injected flag is set. If the injected flag is set, an ignition signal is output to the ignition coil. If the injected flag is not set, as in the case of fuel cut, no ignition signal is output to the ignition coil.

Therefore, when the accelerator is turned off due to deceleration during traveling or in the case of fuel cut (as shown in FIGS. 6 and 7), the process of stopping fuel injection is performed. In the cylinder after the fuel is injected and ignited based on the processing before that, the already-injected flag is not newly set. Therefore, after the engine is stopped, fuel is not injected based on the new process,
Gas is not discharged from the injected cylinder without burning.

FIG. 10 shows a comparison of the fuel injection and ignition timing control processes in the present invention and the conventional system. 10A is a conventional example of the system of the present invention, FIG. 10B is a conventional example of a power supply circuit configuration as shown in FIG. 4 and does not perform special control as in the present invention (Configuration 1), and FIG. FIG. 13 shows the processing state of fuel injection and ignition timing control for each of the conventional examples of the power supply circuit configuration shown in FIG. 13 and the configuration (configuration 2) that does not perform special control as in the present invention.

During running with the engine running, t
It is assumed that an engine stop request is generated at timing 6 with the ignition switch on. According to the method of the present invention, no new fuel is injected after the timing of t6. Further, since the air-fuel mixture of the fourth and second cylinders in which the fuel is injected at the timings of t3 and t5 is ignited, the air-fuel mixture of these cylinders remains unburned.
It is not emitted.

On the other hand, in the conventional example of the configuration 1 shown in FIG.
The fourth and second fuel injections at timings t3 and t5
The mixture of the cylinders is not ignited, and the mixture of these cylinders is discharged without being burned.

In the conventional example of the configuration 2 shown in FIG.
The fourth and second fuel injections at timings t3 and t5
Although the air-fuel mixture in the cylinder is ignited, the ignition is performed after the timing of t11 even though there is no air-fuel mixture to be ignited, so that wasteful power is consumed.

Furthermore, the speed of rotation change when the engine is stopped is large, and the power supply immediately before the engine is stopped becomes abnormally long.
A failure such as a disconnection of the ignition coil may occur.

As described above, according to the present invention, after a predetermined delay time elapses after the fuel injection to each of the cylinders is stopped in response to the engine stop request, for example, this corresponds to 1/2 to several revolutions of the engine. After a lapse of time, the output of the ignition signal corresponding to the fuel injection into each cylinder is stopped.

The present invention is particularly effective in a hybrid vehicle equipped with an engine and a vehicle drive motor.

FIG. 11 shows a running state of a hybrid vehicle to which the present invention is applied. That is, FIG. 11 shows a state in which the hybrid vehicle stops after traveling in the respective driving modes such as warm-up operation, acceleration traveling, and deceleration traveling after the following startup.

(1) Warm-up operation The engine is started by the motor / generator 68 after the ignition switch is turned on. Until the warm-up is completed, the engine is idling in the warm-up operation mode, and the motor / generator 68 functions as a generator driven by the engine.

(2) Stopping the Engine After the warm-up is completed, the engine is temporarily stopped (idle stop).

(3) Motor running When the vehicle is under light load, running and regeneration are performed only by the motor 3.

(4) Stopping the engine When the vehicle is temporarily stopped with the ignition switch on during running, the engine is kept stopped (idle stop).

(5) Engine running power generation When the vehicle is lightly loaded, the vehicle runs only with the motor 3, and in a high vehicle speed range, the engine is started by the motor / generator 68, the clutch is engaged, and the engine is run. The power is generated by the battery 68 and the battery is charged. When a request for higher torque traveling is made by the driver's accelerator operation, torque assist by the motor 3 is performed.

(6) Engine Stop (Fuel Cut) and Deceleration During deceleration, the engine is stopped as much as possible, and energy is recovered by the motor 3 by regenerative control.

(7) Stopping the engine When stopping with the ignition switch on, the engine is stopped (idle stop).

The fuel is cut in the process of shifting to the idle stop after the warm-up operation. However, by performing the fuel injection and ignition timing control processing according to the method of the present invention as shown in FIG. Therefore, the mixture of the plurality of cylinders is not discharged without being burned. In addition, no wasteful ignition power is consumed even though the ignition switch remains on.

Similarly, after the high-speed operation by the engine running power generation, the fuel is cut to stop the engine and shift to the decelerating running. In the process of the present invention as shown in FIG. By performing the injection and ignition timing control processes, it is possible to prevent a mixture of a plurality of cylinders from being discharged without being burned and to consume unnecessary ignition power. In addition, a failure such as a disconnection of the ignition coil does not occur.

Further, in a system in which the hybrid vehicle is driven only by the engine when the charge rate of the battery is low, there are many opportunities to stop the engine. In this case, the same effect is obtained.

Next, FIGS. 12 to 15 show another embodiment of the processing flow in the engine control unit of the present invention.

First, the processing flow of fuel injection control by the fuel injection control program 132 will be described with reference to FIGS. In this embodiment, an injection output process is performed (S50).
Along with 9), a fuel cut signal is generated and output for the cylinder that is the target of the fuel cut. The fuel cut signal is used for the next ignition timing control process.

As shown in FIG. 14, in the processing flow of the ignition timing control, in the delay processing (608), the fuel cut signal is obtained from the engine speed N (or the output of the crank angle sensor) of the engine. After the fuel injection to each cylinder is stopped, a delay signal for delaying by a time length corresponding to about one rotation of the engine is calculated. In the ignition output process (607), the ignition timing, the non-energization angle,
Output processing of an ignition signal is performed using the delayed fuel cut signal in addition to the information of the injected flag.

As shown in FIG. 15, in the ignition output process of this embodiment, an interrupt process is performed based on a predetermined crank angle signal (REF), and the counter starts counting down. Then, when the count value becomes 0, the presence / absence of a fuel cut signal is checked. If there is no fuel cut signal, an ignition signal is output to the ignition coil. If there is a fuel cut signal as in the case of a fuel cut, no ignition signal is output to the ignition coil.

Therefore, when the fuel cut is performed during traveling, the fuel cut signal is delayed by a time length corresponding to about one revolution of the engine and used for the ignition output processing. The gas is not discharged while the gas remains unburned. It should be noted that ignition is performed for a short time even though there is no air-fuel mixture to be ignited. However, since the period is extremely short, no unnecessary power is consumed.

FIG. 16 shows the state of processing of fuel injection and ignition timing control in the embodiment of FIGS.

While the engine is running, the vehicle travels at t in FIG.
It is assumed that an engine stop request is generated at timing 6 with the ignition switch on. According to this method, no new fuel is injected after the timing of t6. Further, since ignition is performed from t6 to a time length corresponding to about one revolution of the engine, that is, t14,
The fourth and second fuel injections at timings t3 and t5
The mixture of the cylinders is ignited, and the mixture of these cylinders is not discharged without being burned. However,
From t10 to t14, ignition is performed even though there is no air-fuel mixture to be ignited. However, since the period is extremely short, no wasteful power is consumed. The length of the delay time can be set as appropriate.

The present invention is also effective when applied to a vehicle equipped with a vehicle driving engine and an AC generator (motor / generator 68) for starting and powering the engine.
FIG. 17 shows, as an example of such a driving running pattern of the vehicle, a state from the following startup to a stop after running in each of the operating modes such as warm-up operation, acceleration running, and deceleration running.

(1) Warm-up operation The engine is started by the motor / generator 68 after the ignition switch is turned on. Until the warm-up is completed, the engine is idling in the warm-up operation mode, and the motor / generator 68 functions as a generator driven by the engine.

(2) Stopping the Engine After the warm-up is completed, the engine is temporarily stopped (idle stop).

(3) Engine running power generation When the vehicle is lightly loaded, the engine is started by the motor / generator 68, the vehicle runs on the engine, and power is generated by the motor / generator 68. At the time of deceleration, the engine is stopped as much as possible, and energy is recovered by the motor / generator 68 by regenerative control.

(4) Stopping the Engine When the vehicle is temporarily stopped with the ignition switch on during running, the engine is kept stopped (idle stop).

(5) Engine running power generation The engine is started by the motor / generator 68,
The clutch is engaged, and the vehicle runs with the engine both when the vehicle is under light load and in a high vehicle speed range, generates power by the motor / generator 68, and charges the battery.

(6) Engine Stop (Fuel Cut) and Deceleration During deceleration, the engine is stopped as much as possible, and energy is recovered by the motor / generator 68 by regenerative control.

(7) Stopping the engine When stopping with the ignition switch on, the engine is stopped (idle stop).

The fuel is cut in the process of shifting to the idle stop after the warm-up operation. However, the fuel injection and the ignition timing control process according to the method of the present invention as shown in FIG. Accordingly, the air-fuel mixture of the plurality of cylinders is not discharged without being burned. In addition, no wasteful ignition power is consumed even though the ignition switch remains on.

The present invention is particularly effective when it is used in a hybrid vehicle in which energy is stored in a large-capacity battery and a motor and an engine are used in combination as a driving force. That is, in such a hybrid vehicle, the engine is stopped as much as possible at an operating point with low engine efficiency (low-speed rotation, light-load operation) or idle operation, thereby preventing waste of fuel. On the other hand, at the operating point where the engine efficiency is high, the engine, the motor 3 and the motor generator 68 are controlled to operate at the efficient points within a range where a desired torque can be obtained, thereby preventing waste of fuel and reducing HC and the like. It is possible to reduce exhaust gas and prevent waste of electric power.

By using the idle stop effectively in a hybrid vehicle, energy consumption can be reduced by nearly 20% as compared with a conventional vehicle that does not perform the idle stop, as shown in FIG. According to the present invention, even when such an idle stop is performed, the air-fuel mixture is not exhausted without being burned, and troubles such as unnecessary consumption of ignition power and disconnection of the ignition coil are eliminated. There are advantages.

[0092]

As described above, according to the present invention, when the engine is stopped, the air-fuel mixture of the plurality of cylinders is not discharged without being burned. Further, when fuel cut such as idling stop or deceleration running is performed while the ignition switch is on, there is no trouble such as wasteful consumption of ignition power or disconnection of the ignition coil due to long-time energization. In particular, it is suitable for reducing the exhaust gas such as HC from the hybrid vehicle and reducing the waste of electric power.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a hybrid vehicle drive device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration example of an engine controlled by the engine control unit of FIG. 1;

FIG. 3 is a diagram showing a configuration example of an engine control unit of FIG. 1;

FIG. 4 is a power supply circuit diagram of a fuel injection device and an ignition timing control device in the device of FIG. 1;

FIG. 5 is a diagram showing a detailed configuration example of the motor control unit of FIG. 1;

FIG. 6 is a diagram showing an example of a processing flow of a fuel injection device in the device of FIG. 1;

FIG. 7 is a view for explaining the processing flow of FIG. 6;

FIG. 8 is a diagram showing an example of a processing flow of the ignition timing control device of FIG. 1;

FIG. 9 is a view for explaining the processing flow of FIG. 8;

FIG. 10 is a diagram showing timings of ignition and fuel injection in the first embodiment of the present invention in comparison with a conventional example.

FIG. 11 is a diagram showing a running state of a hybrid vehicle to which the present invention is applied.

FIG. 12 is a diagram showing another embodiment of the processing flow of the fuel injection device in the device of FIG. 1;

FIG. 13 is a view for explaining the processing flow of FIG. 12;

FIG. 14 is a diagram showing another embodiment of the processing flow of the ignition timing control device of FIG. 1;

FIG. 15 is a view for explaining the processing flow of FIG. 14;

FIG. 16 is a diagram showing timings of ignition and fuel injection in another embodiment of the present invention in comparison with a conventional example.

FIG. 17 is a diagram showing a running state of an engine-driven vehicle to which the present invention is applied.

FIG. 18 is a diagram showing an effect of idling stop running.

19 is a conventional power supply circuit diagram corresponding to FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Control unit, 2 ... Engine, 3 ... Motor, 4 ... Inverter, 5 ... Battery, 11 ... Integrated control unit 11, 12 ... Motor control unit,
13: engine control unit, 132: fuel injection control program, 134: ignition timing control program

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // B60K 6/00 B60K 9/00 Z 8/00 (72) Inventor Naoyuki Ozaki Hitachinaka City, Ibaraki Prefecture No. 2520, Hitachi, Ltd. Automotive Equipment Division (72) Inventor Nobuhiro Akasaka 2520, Ojitakata, Hitachinaka-shi, Ibaraki F-term, Hitachi Automotive Equipment Division F-term (reference) 3G019 AA00 AA05 AB02 AB03 AC05 AC10 CA06 CA11 CB14 DA07 DB16 DB18 DC06 GA01 GA05 GA08 GA09 GA10 GA11 GA18 GA20 3G084 AA00 AA03 BA13 BA16 CA07 DA10 DA28 FA05 FA06 FA07 FA10 FA33 FA36 FA38 3G092 AA01 AC02 BA08 CA01 CB04 CB05 EA16 EA17 FA11 GA01 HE01ZZZZZ JA21 JA32 KA26 KA28 LA00 MA12 MA24 NE22 NE23 PA01Z PA11Z PD03Z PE01Z PE03Z PE08Z PF01Z PF03Z PF10Z PF16 Z

Claims (7)

[Claims] An engine control unit for controlling fuel injection to each cylinder of a spark ignition type multi-cylinder engine and ignition of an air-fuel mixture of each cylinder based on an operation command and an operation state of the engine; The unit stops the fuel injection to each of the cylinders based on the operation command, and after all the ignition signals corresponding to the air-fuel mixture of each of the cylinders by the fuel injected immediately before the stop of the fuel injection are output. A control system for a spark ignition type multi-cylinder engine that stops the output of the ignition signal. 2. A fuel injection type and a spark ignition for each cylinder of the engine are controlled based on an operation command for the spark ignition type multi-cylinder engine and an operation state of the engine. An engine control unit that stops the fuel injection when there is a stop request to the engine; the engine control unit stops fuel injection to each of the cylinders in response to the engine stop request, A control system for a spark ignition type multi-cylinder engine, wherein after a delay time has elapsed, the output of an ignition signal corresponding to fuel injection into each cylinder is stopped. 3. A control system for a spark ignition type multi-cylinder engine according to claim 2, wherein said predetermined delay time is a time corresponding to 1/2 to several revolutions of the engine. Control system for spark ignition multi-cylinder engine. 4. An engine control unit including a fuel injection control program and an ignition control program for controlling fuel injection to each cylinder of the engine and spark ignition to each cylinder based on an operation command and an operation state of the engine. Wherein the engine control unit sets an injection completed flag for each fuel injection for each of the cylinders, and resets the injection completed flag for each spark ignition corresponding to the fuel injection to each of the cylinders. Engine control system. 5. An engine control unit including a fuel injection control program and an ignition control program, the engine control unit controlling fuel injection to each cylinder of the engine and spark ignition to each cylinder based on an operation command and an operation state of the engine. The engine control unit sets an injected flag for each fuel injection for each of the cylinders, resets the injected flag for each spark ignition corresponding to fuel injection for each of the cylinders, A spark ignition type multi-cylinder engine control system that outputs an ignition signal to a corresponding cylinder when is set, and does not output an ignition signal to a corresponding cylinder when the injection completion flag is not set. 6. A vehicle driving engine, a vehicle driving motor, a battery connected to the vehicle driving motor via a power converter, and the engine and the motor are controlled according to a driving state of the vehicle. A drive apparatus for a hybrid vehicle, comprising: a control unit, wherein the control unit is configured to control the engine and the motor based on a plurality of operation modes according to a target torque and a magnitude of a vehicle speed. 5. A drive system for a hybrid vehicle, comprising: the control system for a spark ignition type multi-cylinder engine according to any one of 5. 7. An engine for driving a vehicle, an alternator for starting and powering an engine, and a control unit for controlling the engine and the motor in accordance with a driving state of the vehicle, wherein the control unit has a target torque and a vehicle speed. 6. A driving apparatus for a vehicle including a spark ignition type multi-cylinder engine configured to control the engine and the motor based on a plurality of operation modes according to the magnitude of the engine. A drive device for a vehicle, comprising a control system for a spark ignition type multi-cylinder engine.