JP2002321604A - Vehicle vibration reduction method and device - Google Patents

Abstract

(57) Abstract: A vehicle vibration is reduced when a drive of an internal combustion engine or another vehicle drive source is stopped without generating a shock at the time of starting. When stopping rotation of a crankshaft by a driving force of an M / G (motor generator) ("YES" in S710), a braking force acting on a rear wheel is temporarily reduced (S730). Thus, the torque fluctuation generated when the driving of the M / G is stopped is transmitted to the rubber tire portion of the rear wheel, and the vehicle vibration due to the torque fluctuation can be reduced by the vibration damping function of the rubber tire. This reduction in the braking force is temporary when the M / G drive is stopped (“YES” in S750, S760, S77).
0). Therefore, there is no problem in the braking performance of the vehicle. In addition, since the transmission of torque fluctuation is not prevented by shutting off a power transmission system such as an automatic transmission (A / T), no shock occurs when the engine is started.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention reduces a vehicle vibration generated when the driving force is stopped in a state where the driving force is transmitted to a power transmission system to wheels and a braking force is acting on the wheels. The present invention relates to a vehicle vibration reduction method and a vehicle vibration reduction device.

[0002]

2. Description of the Related Art Conventionally, an economy running system (hereinafter referred to as an "eco-run system") has been used in an internal combustion engine for a vehicle. This eco-run system is designed to automatically stop the internal combustion engine when the car stops running at an intersection, etc., and to start the car by automatically starting the internal combustion engine when starting operation to improve fuel efficiency. This is an automatic stop / start system.

[0003] However, in such an automatic stop of the internal combustion engine, since the driver is not aware of the stop, the vehicle vibration caused by the torque fluctuation when the internal combustion engine stops rotating may give the driver an uncomfortable feeling. There is.

For this reason, in Japanese Patent Application Laid-Open No. 2000-170894, at the time of automatic stop, hydraulic oil of a clutch (for example, C1 clutch) necessary for starting inside the automatic transmission is drained. As a result, the engagement state of the clutch is temporarily released, so that torque fluctuations when the rotation of the internal combustion engine is stopped are prevented from being transmitted to the wheels, thereby preventing the occurrence of vehicle vibration.

[0005]

However, when the hydraulic oil of the automatic transmission is drained as in the prior art, it is necessary to supply the hydraulic oil to the C1 clutch or the like and connect it when starting the automatic transmission. . However, since hydraulic oil is supplied after the internal combustion engine is started, the torque of the internal combustion engine is rapidly transmitted to the power transmission system when the C1 clutch or the like is connected. This may cause a shock during automatic starting.

The present invention provides a vehicle vibration reduction method and apparatus capable of reducing vehicle vibration due to torque fluctuations caused by stopping the driving of an internal combustion engine and other vehicle driving sources without generating such a shock at the time of starting. The purpose is to provide.

[0007]

The means for achieving the above object and the effects thereof will be described below. The vehicle vibration reducing method according to claim 1, wherein the vehicle vibration generated when the driving force is stopped is reduced in a state where the driving force is transmitted to the power transmission system to the wheels and the braking force is acting on the wheels. A vehicle vibration reducing method, wherein the vehicle vibration is reduced by temporarily reducing a braking force of a wheel when the driving force is stopped.

When the driving force is stopped while the driving force is being transmitted to the power transmission system to the wheels, the driving force suddenly drops, causing a shock in the power transmission system. Is transmitted to the vehicle body and attempts to cause vehicle vibration. However, as in the present invention, when the braking force of the wheels is temporarily reduced when the driving force is stopped, the torque fluctuation due to the stopping of the driving force is transmitted to the wheels. Thus, the shock due to the torque fluctuation is absorbed by the vibration damping function of the wheels, and the vehicle vibration can be reduced.

The reduction of the braking force may be a temporary one when the driving force is stopped, so that there is no problem in the braking performance of the vehicle. In addition, since the transmission of the torque fluctuation is not prevented by shutting off the power transmission system or the like, no shock is generated when the driving force is generated again. The reduction of the braking force includes both reducing the braking force and completely eliminating the braking force.

According to a second aspect of the present invention, in the vehicle vibration reducing method according to the first aspect, a driving force is transmitted to the power transmission system by an internal combustion engine, and the driving force is stopped by the internal combustion engine. Is stopped by stopping the driving of the motor.

As described above, the form of stopping the driving force is as follows.
There is a case where the driving of the internal combustion engine is stopped from the state where the internal combustion engine is driving and outputting the driving force. Therefore, in this manner, the occurrence of vehicle vibration can be reduced with respect to the torque fluctuation when the rotation of the internal combustion engine stops. In addition, no shock occurs in the subsequent start of the internal combustion engine.

According to a third aspect of the present invention, in the vehicle vibration reducing method according to the first aspect, a driving force is applied to the power transmission system by another driving source that is rotating an internal combustion engine that is already stopped. The driving force is transmitted, and the driving force is stopped by stopping the driving of the other driving source.

As described above, the form of stopping the driving force is as follows.
Not from the state where the internal combustion engine is driving and outputting driving force, the internal combustion engine is already in a driving stop state, and this internal combustion engine is rotated by driving of another driving source, and the driving force is transmitted to the power transmission system. Is stopped, the rotation of the internal combustion engine is stopped by stopping the drive of the other drive source. Therefore, in this manner, the occurrence of vehicle vibration can be reduced with respect to torque fluctuation when another driving source stops driving. In addition, no shock occurs even if the internal combustion engine is started or another drive source is driven thereafter.

According to a fourth aspect of the present invention, in the configuration of the third aspect, the rotation of the internal combustion engine by the other drive source is a process temporarily executed immediately after the internal combustion engine is stopped. It is characterized by the following.

The rotation of the internal combustion engine by another drive source that is temporarily executed immediately after the stop of the driving of the internal combustion engine causes a decrease in torque fluctuation due to an increase in the in-cylinder negative pressure of the internal combustion engine and a securing of a brake negative pressure. Or to reduce creep force. In such a case, the vehicle vibration can be effectively reduced by reducing the braking force of the wheels when the driving of the other driving source stops.

According to a fifth aspect of the present invention, in the vehicle vibration reducing method according to the fourth aspect, the braking force is reduced during a period from when the driving of the internal combustion engine is stopped to when the driving of the other driving source is stopped. Features.

In the case where the driving of the internal combustion engine is stopped and the internal combustion engine is once rotated by another driving source, then the driving of the other driving source is stopped to stop the rotation of the internal combustion engine. The braking force may be reduced during a period from the time when the driving of the other driving source is stopped to the time when the driving of the other driving source is stopped. During the period in which the internal combustion engine is rotated by another drive source from the stop of the internal combustion engine and the rotation of the internal combustion engine is stopped by the other drive source, a step may temporarily occur in the driving force. May cause vehicle vibration. Therefore, the braking force may be continuously reduced during the period from when the driving of the internal combustion engine is stopped to when the driving of the other driving source is stopped. In this case, since the rotation of the internal combustion engine by another drive source is temporary, the reduction of the braking force is also short, and there is no problem in the braking performance of the vehicle.

According to a sixth aspect of the present invention, in the vehicle vibration reducing method according to the fourth aspect, when the driving of the internal combustion engine is stopped,
It is characterized in that the braking force is temporarily reduced at each time when the driving of the other driving source is stopped.

When the driving of the internal combustion engine is stopped, the internal combustion engine is once rotated by another driving source, and then the driving of the other driving source is stopped to stop the rotation of the internal combustion engine, The braking force may be temporarily reduced twice, when the driving is stopped and when the driving of the other driving source is stopped.

When the internal combustion engine is rotated by another drive source after the internal combustion engine is stopped, a step may temporarily occur in the driving force, and in such a case, the vehicle may be vibrated. Therefore, the vehicle vibration is reduced by temporarily reducing the braking force when the driving of the internal combustion engine is stopped, and the braking force is temporarily reduced when the rotation of the internal combustion engine is stopped by stopping the driving of another drive source. May be reduced.

Since the reduction of each braking force is temporary, there is no problem in the braking performance of the vehicle. In the vehicle vibration reduction method according to the seventh aspect, in the configuration according to any one of the second to sixth aspects, the driving stop of the internal combustion engine is a process that is automatically executed when an internal combustion engine stop condition is satisfied. It is characterized by.

In a situation where the rotation of the internal combustion engine is stopped while the rotation of the internal combustion engine is being transmitted to the wheels and the braking force is acting on the wheels, the internal combustion engine is automatically turned off when the internal combustion engine stop condition is satisfied. A case where the rotation is stopped is performed.

Such a process of automatically stopping the rotation of the internal combustion engine results in an unintended stop by the driver, so that the occupant is likely to feel uncomfortable due to vehicle vibration. However, in such a case, in the present invention, when the driving of the internal combustion engine or the driving of another driving source is stopped, the braking force is temporarily reduced to reduce the vehicle vibration. The effect of not giving it is remarkable. Further, since the transmission of torque fluctuations is not prevented by, for example, shutting off the power transmission system, a shock does not occur at the time of automatic start of the internal combustion engine that is performed thereafter, so that the driver can feel more uncomfortable. Can not be given.

According to an eighth aspect of the present invention, in the vehicle vibration reducing method according to any one of the first to seventh aspects, the braking force reduction target is a driving wheel. By setting the braking force to be reduced to the driving wheels, vehicle vibration due to torque fluctuation transmitted from the power transmission system to the driving wheels can be efficiently reduced by the vibration damping function of the driving wheels.

According to a ninth aspect of the invention, there is provided a vehicle vibration reducing method according to any one of the first to seventh aspects, wherein the target for reducing the braking force is a driven wheel. The torque fluctuation is transmitted not only to the drive wheels from the power transmission system but also to the vehicle body directly or indirectly from various drive sources without passing through the power transmission system. As a result, torque fluctuations are transmitted from the vehicle body to the driven wheels in the form of vibration.

Accordingly, even when the braking force is to be reduced for the driven wheels, the vehicle vibration can be reduced by the vibration damping function of the driven wheels. In a vehicle vibration reducing method according to a tenth aspect, in the configuration according to any one of the first to seventh aspects, the reduction target of the braking force is a drive wheel and a driven wheel.

It should be noted that, for the reasons described in the eighth and ninth aspects, the braking force may be reduced for both the driving wheels and the driven wheels. As a result, vehicle vibration can be reduced more effectively.

[0028] In the vehicle vibration reducing device according to the eleventh aspect, when the driving force is transmitted from the driving source to the power transmission system to the wheels, and the braking force is applied to the wheels by the braking mechanism, the driving is performed. A vehicle vibration reduction device that reduces vehicle vibration generated when a driving force from a source is stopped, wherein a driving source driving stopping unit that stops driving of the driving source, and driving of a driving source by the driving source driving stopping unit is performed. And a braking force adjusting means for adjusting the braking mechanism so as to temporarily reduce the braking force applied to the wheels when the vehicle is stopped.

When the braking force adjusting means adjusts the braking mechanism so as to temporarily reduce the braking force on the wheels when the driving of the driving source is stopped by the driving source driving stopping means, when the driving of the driving source is stopped. The resulting torque fluctuation is transmitted to the wheels. As a result, vehicle vibration due to torque fluctuation is reduced by the vibration damping function of the wheels.

The braking force can be reduced by the braking force adjusting means only temporarily when the driving of the driving source is stopped, so that there is no problem in the braking performance of the vehicle. In addition, since the transmission of the torque fluctuation is not prevented by shutting off the power transmission system or the like, no shock is generated when the driving force is generated again. The reduction of the braking force performed by the braking force adjusting means includes both reducing the braking force and completely eliminating the braking force.

[0031] In the vehicle vibration reducing device according to the twelfth aspect,
The structure according to claim 11, wherein the drive source is an internal combustion engine. By using the internal combustion engine as the drive source, the drive source drive stopping means stops the drive source by stopping the drive from the state in which the internal combustion engine itself is driven.
Then, when the driving of the internal combustion engine is stopped, the occurrence of vehicle vibration can be reduced by the braking force adjusting means. In addition, the transmission of torque fluctuation is not prevented by, for example, shutting off the power transmission system, so that no shock is generated in the subsequent startup of the internal combustion engine.

[0032] In the vehicle vibration reducing device according to the thirteenth aspect,
According to the eleventh aspect, the driving source is another driving source that rotates an internal combustion engine that is already in a driving stop state.

As described above, by setting the drive source to another drive source that is rotating the internal combustion engine that is already in a stopped state, the drive source drive stopping means can be switched from the state in which the internal combustion engine itself is driven. In addition, there is a configuration in which the drive of another drive source is stopped from a state where the internal combustion engine is already in a drive stop state and the internal combustion engine is being rotated by the drive of another drive source. Then, when the driving of the other driving source is stopped in this way, the occurrence of vehicle vibration can be reduced by the braking force adjusting means. Moreover, transmission of torque fluctuations is not prevented by shutting off the power transmission system, etc.
No shock is generated in the subsequent start of the internal combustion engine or the driving of another drive source.

[0034] In the vehicle vibration reducing device according to the fourteenth aspect,
14. The configuration according to claim 13, wherein the drive source drive stopping means stops driving of the internal combustion engine, and temporarily rotates the internal combustion engine by the other drive source immediately after the stop of driving of the internal combustion engine. It is characterized in that the rotation of the internal combustion engine is stopped by stopping the driving of another driving source.

As described above, the rotation of the internal combustion engine by another driving source, which is temporarily executed immediately after the driving of the internal combustion engine is stopped by the driving source drive stopping means, is caused by the increase in the negative pressure in the cylinder of the internal combustion engine. This is executed to reduce the fluctuation, secure the brake negative pressure, or reduce the creep force. Even in such a case, when the driving of the other driving sources is stopped by the driving source driving stopping means and the rotation of the internal combustion engine is stopped, the braking force adjusting means reduces the braking force of the wheels, thereby reducing the vehicle vibration. Can be effectively reduced.

In the vehicle vibration reducing device according to the fifteenth aspect,
According to a fourteenth aspect of the present invention, the braking force adjusting means reduces the braking force during a period from when the driving of the internal combustion engine is stopped to when the driving of the other driving source is stopped.

The drive source drive stopping means stops the drive of the internal combustion engine, temporarily rotates the internal combustion engine by another drive source, and then stops the drive of the other drive source to stop the rotation of the internal combustion engine. In such a case, the braking force adjusting means may be configured to reduce the braking force during a period from when the driving of the internal combustion engine is stopped to when the driving of the other driving source is stopped.

During the period in which the drive source drive stopping means rotates the internal combustion engine by another drive source after the drive of the internal combustion engine is stopped, and stops the rotation of the internal combustion engine by the other drive source, a step difference is temporarily generated in the drive force. And in such cases may cause vehicle vibration. For this reason, the braking force adjusting means may be configured to continuously reduce the braking force during a period from when the driving of the internal combustion engine is stopped to when the driving of the other driving source is stopped. In this case, since the rotation of the internal combustion engine by the other drive source is temporary, the reduction of the braking force by the braking force adjusting means is also short, and there is no problem in the braking performance of the vehicle.

In the vehicle vibration reducing device according to the sixteenth aspect,
The configuration according to claim 14, wherein the braking force adjusting means temporarily reduces the braking force when the driving of the internal combustion engine is stopped and when the driving of the other driving source is stopped. I do.

The drive source drive stopping means stops the drive of the internal combustion engine, temporarily rotates the internal combustion engine by another drive source, and then stops the drive of the other drive source to stop the rotation of the internal combustion engine. In the case of having the configuration, the braking force adjusting unit is configured to stop driving the internal combustion engine and stop driving the other drive source.
It may be configured to temporarily reduce the braking force twice.

As described above, when the drive source drive stopping means stops the drive of the internal combustion engine and rotates the internal combustion engine by another drive source, and when the rotation of the internal combustion engine by another drive source is stopped, There is a possibility that a step difference is generated in the driving force, and in such a case, there is a possibility that a vehicle vibration is caused. For this reason, the braking force adjusting means temporarily reduces the braking force when the driving of the internal combustion engine is stopped to reduce vehicle vibration, and also temporarily when the rotation of the internal combustion engine is stopped due to the driving stop of another driving source. You may comprise so that a vehicle vibration may be reduced by reducing a braking force. Since the braking force is temporarily reduced by the braking force adjusting means, there is no problem in the braking performance of the vehicle.

In the vehicle vibration reducing device according to the seventeenth aspect,
The configuration according to any one of claims 12 to 16, wherein the drive source drive stopping means automatically stops driving the internal combustion engine when an internal combustion engine stop condition is satisfied.

The drive source drive stopping means may be configured to automatically stop the rotation of the internal combustion engine when the internal combustion engine stop condition is satisfied. In this way, the process in which the drive source drive stopping means automatically stops the rotation of the internal combustion engine is an unintended stop by the driver, so that the occupant is likely to feel uncomfortable due to the vehicle vibration. However, in such a case, in the present invention, since the braking force adjusting means temporarily reduces the braking force to reduce the vehicle vibration, the effect of preventing the driver from feeling uncomfortable is remarkable. . Further, since the transmission of torque fluctuations is not prevented by, for example, shutting off the power transmission system, a shock does not occur at the time of automatic start of the internal combustion engine that is performed thereafter, so that the driver can feel more uncomfortable. Can not be given.

[0044] In the vehicle vibration reducing device according to the eighteenth aspect,
The configuration according to any one of claims 11 to 17, wherein the braking force adjusting means adjusts the braking mechanism so as to temporarily reduce the braking force on the drive wheels.

The braking force adjusting means effectively reduces the vehicle vibration due to the torque fluctuation transmitted from the power transmission system to the driving wheels by using the driving wheels as the braking force reduction target. Can be done.

In the vehicle vibration reducing device according to the nineteenth aspect,
The configuration according to any one of claims 11 to 17, wherein the braking force adjusting unit adjusts the braking mechanism so as to temporarily reduce a braking force on a driven wheel.

The torque fluctuation is transmitted not only from the power transmission system to the drive wheels but also directly or indirectly from the internal combustion engine or another driving source to the vehicle body without passing through the power transmission system. Thus, torque fluctuations of the internal combustion engine are transmitted from the vehicle body to the driven wheels in the form of vibration.

Therefore, the braking force adjusting means can reduce the vehicle vibration by the function of damping the driven wheels by setting the target of the braking force reduction to the driven wheels. In the vehicle vibration reduction device according to the twentieth aspect, the eleventh to seventeenth aspects are described.
Wherein the braking force adjusting means adjusts the braking mechanism so as to temporarily reduce a braking force on a driving wheel and a driven wheel.

For the reasons described in claims 18 and 19, the braking force adjusting means may reduce the braking force to both the driving wheels and the driven wheels. As a result, vehicle vibration can be reduced more effectively.

[0050]

[First Embodiment] FIG. 1 is a system configuration diagram of an internal combustion engine for a vehicle to which the above-described invention is applied and a control device thereof. Here, a gasoline engine (hereinafter, referred to as “engine”) 2 is used as an internal combustion engine.

The output of the engine 2 is output from the crankshaft 2a of the engine 2 to the output shaft 6a via the torque converter 4 and the automatic transmission (hereinafter referred to as "A / T") 6. Is transmitted to the wheels. Further, apart from such a driving force transmission system from the engine 2 to the wheels, the output of the engine 2 is transmitted to the belt 14 via the pulley 10 connected to the crankshaft 2a. The other pulleys 16 and 18 are rotated by the torque transmitted by the belt 14. The pulley 10 is provided with an electromagnetic clutch 10a, which is turned on (connected) and turned off (disconnected) as required, and transmits and receives output between the pulley 10 and the crankshaft 2a.
Non-transmission can be switched.

Of the pulleys 16 and 18, the pulley 16 is connected to a rotating shaft of accessories 22, and can be driven by the torque transmitted from the belt 14. Auxiliary equipment 2
2 corresponds to, for example, an air conditioner compressor, a power steering pump, an engine cooling water pump, and the like. Although shown in FIG. 1 as a single accessory 22, there are actually a compressor for an air conditioner, a power steering pump, and a water pump for cooling the engine.
It is designed to rotate in conjunction with.

A motor generator (hereinafter referred to as “M / G”) 26 is linked to the belt 14 by the pulley 18. This M / G 26 functions as a generator as required (“power generation mode” or “regeneration mode”),
The torque of the engine 2 transmitted from the pulley 18 is converted into electric energy. Further, the M / G 26 functions as a motor as needed (“drive mode”), so that the pulley 1
The belt 14 is rotated via the motor 8 to rotate one or both of the engine 2 and the accessories 22.

Here, the M / G 26 is electrically connected to the inverter 28. When the M / G 26 is set to the power generation mode or the regenerative mode, the inverter 28 switches from the M / G 26 to the high voltage power supply (36 V in this case).
Battery 30 and DC / DC converter 3
2 for a low-voltage power supply (12 V in this case)
, And further switched to be a power source for the ignition system, meters, ECUs (electronic control units) and others.

When the M / G 26 is set to the “drive mode”, the inverter 28 supplies power to the M / G 26 from the high-voltage power supply battery 30 which is a power source, so that the M / G 2
6 is driven via the pulley 18 and the belt 14 to rotate the accessories 22 when the engine is stopped, and to rotate the crankshaft 2a when automatically starting, automatically stopping, or starting the vehicle. The inverter 28 can adjust the rotation speed of the M / G 26 by adjusting the supply of electric energy from the high-voltage power supply battery 30.

A starter 36 is provided for starting the engine at the time of cold start. The starter 36 is supplied with electric power from the low-voltage power supply battery 34, rotates the ring gear, and starts the engine 2.

The A / T 6 is provided with an electric hydraulic pump 38 supplied with electric power from the low-voltage power supply battery 34, and supplies hydraulic oil to a hydraulic control unit inside the A / T 6. This hydraulic oil adjusts the operating state of the clutch, brake and one-way clutch inside the A / T 6 by a control valve in the hydraulic control unit, and switches the shift state as necessary.

The on / off switching of the electromagnetic clutch 10a, the mode control of the M / G 26 and the inverter 28,
The control of the starter 36 and the control of the amount of stored power for the batteries 30 and 34 (not shown) are executed by the eco-run ECU 40. Auxiliary equipment 2 except water pump
2 drive ON / OFF, drive control of the electric hydraulic pump 38, A
/ T6 shift control, fuel injection control by a fuel injection valve (intake port injection type or in-cylinder injection type) 42, throttle valve 4 provided in intake pipe 2b by electric motor 44
6 opening control and other engine control
This is executed by U48. In addition, since the vehicle stability control (VSC) -ECU 50 is provided, braking control for the braking mechanism of each wheel is executed. These ECUs 40, 48, and 50 exchange instructions and data with each other by data communication.

The eco-run ECU 40 is provided with the M / G 26
The rotation speed sensor of the M / G 26 is detected from a rotation speed sensor built in the MPU, and the presence / absence of activation of the eco-run system by the driver and other data are detected from the eco-run switch.
Further, the engine ECU 48 calculates the engine cooling water temperature THW from the water temperature sensor, the accelerator pedal depression state from the idle switch, the accelerator opening ACCP from the accelerator opening sensor, the steering angle θ from the steering angle sensor,
From vehicle speed sensor to vehicle speed SPD, throttle opening sensor 46
a, the throttle opening TA from the shift position sensor, the shift position SHFT from the shift position sensor, the engine speed NE from the engine speed sensor, the on / off operation from the air conditioner switch,
Other data is detected for engine control and the like.

The VSC-ECU 50 detects operation data of the brake pedal 52 for braking control and the like. The brake pedal 52 is provided with a brake switch 52a, and outputs a signal indicating the depression state BSW of the brake pedal 52 to the VSC-ECU 50. That is, when the brake pedal 52 is not depressed, the brake switch 52a outputs an off (OFF) signal.
When 2 is depressed, an ON signal is output. Further, the VSC-ECU 50 detects a master cylinder oil pressure from a master cylinder oil pressure sensor 202 described later, a wheel speed of each wheel from a wheel speed sensor 204, and the like.

A brake booster 56 is provided as a booster for increasing the depressing force of the brake pedal 52. The brake booster 56 includes a diaphragm 56
a formed in two pressure chambers 56b, 5
6c. Among them, a brake booster pressure sensor 56d is provided in the first pressure chamber 56b, detects the brake booster pressure BBP in the first pressure chamber 56b, and outputs a signal corresponding to the brake booster pressure BBP. The intake negative pressure is supplied to the first pressure chamber 56b from the surge tank 2c via a check valve 56e. The check valve 56e is connected to the surge tank 2 from the first pressure chamber 56b.
The flow of air to c is allowed, and the reverse flow is prohibited.

The brake booster 56 functions as follows. That is, when the brake pedal 52 is not depressed, the negative pressure control valve 56f provided in the brake booster 56 reduces the negative pressure in the first pressure chamber 56b to the second pressure.
It is introduced into the pressure chamber 56c. Therefore, the first pressure chamber 56
Since b and the second pressure chamber 56c are in the same negative pressure state, the diaphragm 56a is pushed back to the brake pedal 52 side by the spring 56g. Therefore, the push rod 56h interlocked with the diaphragm 56a does not push a piston (not shown) in the master cylinder 56i.

On the other hand, when the brake pedal 52 is depressed, the input rod 56 provided on the brake pedal 52 is depressed.
j, the negative pressure control valve 56f is connected to the first pressure chamber 56b.
And the second pressure chamber 56c, and the atmosphere is introduced into the second pressure chamber 56c. As a result, the first pressure chamber 56b in the intake negative pressure state and the second pressure chamber 5 at atmospheric pressure
6c. As a result, the depression force on the brake pedal 52 is doubled, and the diaphragm 56
“a” pushes the push rod 56h toward the master cylinder 56i against the urging force of the spring 56g. As a result, the piston in the master cylinder 56i is pushed to perform braking.

When the brake pedal 52 is depressed, the input rod 5 provided on the brake pedal 52 is released.
6j, the negative pressure control valve 56f is connected to the second pressure chamber 56.
c and the outside air side are cut off, and the first pressure chamber 56b and the second
A communication state is established with the pressure chamber 56c. Thereby, the intake negative pressure is introduced into the second pressure chamber 56c from the first pressure chamber 56b. Therefore, the first pressure chamber 56b and the second pressure chamber 5
6c has the same pressure. Therefore, the diaphragm 56a moves toward the brake pedal 52 by the urging force of the spring 56g, and returns to the original non-braking state.

Next, a detailed hydraulic circuit of the braking mechanism controlled by the VSC-ECU 50 is shown in FIG. here,
The master cylinder 56i is of a tandem type, and has a configuration in which two pressurizing pistons (not shown) are slidably fitted in a housing (not shown) in series with each other. Thus, two pressure chambers (not shown) are formed in the housing in front of each pressure piston independently of each other. The master cylinder 56i mechanically generates the same hydraulic pressure in each of the pressurizing chambers according to the brake operation force that is the depression force of the brake pedal 52.

The braking mechanism according to the first embodiment is of a front-rear two-system type. A brake cylinder 66 for operating the brakes 64 of the left and right front wheels FL and FR is connected to one pressurizing chamber of the master cylinder 56i. ing. Further, a brake cylinder 70 for operating the respective brakes 68 of the left and right rear wheels RL, RR is connected to the other pressurizing chamber.

In the front-wheel-side hydraulic system, the master cylinder 56i and the brake cylinders 66 of the left and right front wheels FL and FR are connected by a main oil passage 74. In the rear-wheel-side hydraulic system, the master cylinder 56i is connected to the master cylinder 56i. The main oil passage 75 is connected to the brake cylinders 70 of the left and right rear wheels RL and RR. These main oil passages 7
4 and 75 are branched after extending from the master cylinder 56i, thereby forming one main passage 76, 77 and 2 respectively.
The branch passages 78 and 79 are connected to each other. In the middle of the main passages 76 and 77, a pressure control valve 8 is provided.
0, 81 are provided. The above-described brake cylinders 66 and 70 are connected to the distal ends of the branch passages 78 and 79, respectively. In the main oil passages 74 and 75, pump passages 82 and 83 are connected to portions between the pressure control valves 80 and 81 and the brake cylinders 66 and 70, and self-supply pumps 84 and 85 are provided in the middle thereof. I have. Self-sufficient pump 8
4 and 85 are driven by a self-supply pump motor 86.

The pressure control valves 80 and 81 control the communication between the master cylinder 56i and the brake cylinders 66 and 70, and are of a type that electromagnetically controls the pressure difference between them. It is. That is, as shown in FIG. 3, the pressure control valves 80 and 81 are connected to a housing (not shown).
And master cylinder 56i in main oil passages 74 and 75
90 that controls the flow of hydraulic oil between the brake cylinders 66 and 70 and the valve seat 92 on which the valve 90 is to be seated, and controls the relative movement of the valve 90 and the valve seat 92. A solenoid 94 for generating a magnetic force.

In the pressure control valves 80 and 81, as shown in FIG. 3A, in a non-operating state (OFF state) where the solenoid 94 is not excited, the valve body 90 is moved from the valve seat 92 by the elastic force of the spring 96. Are separated. This allows a bidirectional flow of hydraulic oil between the master cylinder 56i and the brake cylinders 66, 70 in the main oil passages 74, 75. As a result, if the brake operation is performed, the brake cylinder 66 , 70 are changed at the same pressure as the master cylinder 56i. During this braking operation, a force acts on the valve element 90 in a direction away from the valve seat 92, so that even if the master cylinder oil pressure, that is, the brake cylinder oil pressure becomes high, the valve element 90 will not be operated unless the solenoid 94 is excited. There is no sitting on the seat 92. That is, the pressure control valves 80 and 81 are configured as normally open valves.

On the other hand, as shown in FIG. 3B, in the operation state (ON state) where the solenoid 94 is excited,
The armature 98 is attracted by the magnetic force of the solenoid 94, and the valve 9 moves integrally with the armature 98.
0 is seated on the valve seat 92. At this time, the valve body 90 has the suction force F1 based on the magnetic force of the solenoid 94, the sum of the differential pressure acting force F2 based on the difference between the brake cylinder oil pressure and the master cylinder oil pressure, and the elastic force F3 of the spring 96. Acts in opposite directions. In a region where the suction force F1 is large with respect to the differential pressure acting force F2 based on the difference between the brake cylinder oil pressure and the master cylinder oil pressure and “F2 ≦ F1-F3” is satisfied, the valve body 90 is seated on the valve seat 92, The connection between the brake cylinders 66 and 70 and the master cylinder 56i is shut off. As a result, the brake cylinders 66, 7
The hydraulic pressure of 0 can be controlled independently. For example, as described later, the hydraulic pressure of the brake cylinders 66 and 70 is reduced, for example, "0".
As a result, the braking force can be eliminated.

As shown in FIG. 2, the pressure control valves 80, 81 are provided with bypass passages 102, 103, and bypass valves 104, 105 are provided in the bypass passages 102, 103 as check valves. Is provided. For some reason, when the brake pedal 52 is depressed, the pressure control valves 80 and 81 are closed due to the fluid force generated in the movable members in the pressure control valves 80 and 81, or the pressure control valve 8
Even if 0 and 81 are mechanically locked and remain closed, the flow of hydraulic oil from the master cylinder 56i to the brake cylinders 66 and 70 is ensured.

In the middle of each of the branch passages 78 and 79, the brake cylinder 66,
On the 70 side, holding valves 110 and 11 which are normally open electromagnetic on-off valves are provided.
1 are provided two each. Holding valves 110, 11
Reference numeral 1 denotes a state in which the cylinder is excited to be closed, and in this state, the flow of hydraulic oil from the brake cylinders 66, 70 to the master cylinder 56i and the self-supply pumps 84, 85 is blocked, whereby the brake cylinder oil pressure is maintained. To achieve. Each of the holding valves 110 and 111 has a bypass passage 11.
2 and 113 are connected, and each bypass passage 112 and 113 is connected.
Are provided with bypass valves 114 and 115 for returning hydraulic oil as check valves.

The holding valve 11 in each of the branch passages 78 and 79
Reservoir passages 116 and 117 extend from portions between the cylinders 0 and 111 and the brake cylinders 66 and 70, respectively.
8,119. Each reservoir passage 116, 11
In the middle of 7, a pressure reducing valve 120, 1 which is a normally closed solenoid on-off valve
21 are provided. These pressure reducing valves 120 and 121 are
It is excited to be in an open state, and in this state, the flow of hydraulic oil from the brake cylinders 66, 70 to the reservoirs 118, 119 is allowed. As a result, the brake cylinder oil pressure in each of the brake cylinders 66 and 70 can be reduced as necessary, and the braking force can be reduced.

The reservoirs 118 and 119 are formed by fitting the reservoir pistons 122 and 123 to the housing in a substantially airtight and slidable manner, and are formed in front of the reservoir pistons 122 and 123 by this fitting. In the reservoir chambers 124 and 125, hydraulic oil is stored under pressure by springs 126 and 127. The reservoir chambers 124 and 125 are connected to the pump passages 82 and 125, respectively.
83 connects to the main oil passages 74 and 75.

The pump passages 82 and 83 are provided with self-supply pumps 84 and 83, respectively.
85, the passages are partitioned into suction passages 130 and 131 and discharge passages 132 and 133, respectively.
0, 131, 132, 133 are provided with suction valves 134, 135 and discharge valves 136, 137, respectively, which are check valves. In the pump passages 82 and 83,
Damper chambers 138, 139 and orifices 138a, 139
a are provided in series with each other on the discharge side of the self-supply pumps 84 and 85, thereby reducing the pulsation of the self-supply pumps 84 and 85.

The suction valve 13 of the suction passages 130 and 131
The portion between 4,135 and reservoirs 118, 119 is
The supply passages 140 and 141 are connected to portions of the main oil passages 74 and 75 between the master cylinder 56i and the pressure control valves 80 and 81. In the middle of the supply passages 140 and 141, an inflow control valve 142 as an electromagnetic supply control valve,
143 are provided. Inflow control valves 142, 143
Is a normally closed electromagnetic on-off valve, which is switched from a closed state (OFF: supply blocking state) to an open state (ON: supply state) when the solenoid is excited. Inhalation passage 13
0, 131, the check valve 14 is provided at a portion between the connection point with the supply passages 140, 141 and the reservoirs 118, 119.
4,145 are provided. These check valves 144, 14
Reference numeral 5 is provided to prevent the hydraulic oil from flowing into the reservoirs 118 and 119 from the master cylinder 56i when the inflow control valves 142 and 143 are open. The check valves 144 and 145 ensure that the hydraulic oil from the master cylinder 56i is sucked into the self-supply pumps 84 and 85 at a high pressure. The reservoir passages 116, 11
7 is a non-return valve 144, 14 of the suction passages 130, 131.
5 and reservoirs 118 and 119.
In addition, each of the two check valves 13 of the suction passages 130 and 131
4, 135, 144, and 145, a sub-supply passage 150 branched and extending from the master reservoir 146 is also connected. In the branching subsupply passage 150, a subflow control valve 152 and a check valve 154 are arranged in series with respect to the front wheel side. Only the secondary inflow control valve 153 is provided on the rear wheel side.

As described above, the master cylinder 56i and the master reservoir 146 are provided on the suction side of the self-supply pumps 84 and 85.
Are connected via the supply passages 140 and 141 and the auxiliary supply passage 150, respectively. For example, at the time of traction control and vehicle stability control, hydraulic oil is supplied from the master reservoir 146 via the auxiliary supply passage 150. For example, at the time of effectiveness characteristic control, hydraulic oil is supplied from the supply passages 140 and 141. You.

The check valve 154 includes two inflow control valves 14.
2 and 152 are provided to prevent the hydraulic oil from flowing out of the master cylinder 56i to the master reservoir 146 when both of them are opened. Note that the check valve 154 may be provided also in the supply passage on the rear wheel side.

In the main oil passage 75, a master cylinder oil pressure sensor 202 is provided to detect the oil pressure of the master cylinder 56i. Since a hydraulic pressure corresponding to the operation amount of the brake pedal 52 is generated in the master cylinder 56i, the brake operation amount can be obtained from the master cylinder oil pressure. Also, each wheel FL, FR, RL, RR
Is provided with a wheel speed sensor 204 for each wheel FL, F
The wheel speeds of R, RL, and RR are detected. Based on the wheel speed, a braking slip state, wheel acceleration, and the like are obtained, and antilock control and the like are performed based on these.

Next, of the controls executed by the ECUs 40, 48, and 50, the control of the parts related to the present invention will be described. First, an automatic stop process executed by the eco-run ECU 40 is shown in a flowchart of FIG. This process is a process repeatedly executed in a short period. Steps in the flowchart corresponding to each processing content are denoted by “S
~ ".

When the automatic stop processing is started, first, an operation state for judging execution of automatic stop is read (S
110). For example, the engine cooling water temperature THW detected from the water temperature sensor, the presence or absence of depression of the accelerator pedal detected from the idle switch, the voltage of the batteries 30, 34, the presence or absence of the depression of the brake pedal 52 detected from the brake switch 52a, and the vehicle speed sensor The detected vehicle speed SPD or the like is read into a work area of the RAM inside the eco-run ECU 40.

Next, it is determined from these operating states whether or not the automatic stop condition is satisfied (S120). For example,
(1) A state in which the engine 2 has been warmed up and has not been overheated (the engine cooling water temperature THW is lower than the water temperature upper limit,
(2) The state where the accelerator pedal is not depressed (idle switch is on), (3)
A state in which the charged amounts of the batteries 30 and 34 are at required levels, (4) a state in which the brake pedal 52 is depressed (the brake switch 52a is on), and (5) a state in which the vehicle is stopped (vehicle speed). SPD is 0km /
h), it is determined that the automatic stop condition is satisfied when all of the conditions (1) to (5) are satisfied.

If any one of the above conditions (1) to (5) is not satisfied, the automatic stop condition is determined to be unsatisfied (S1).
("NO" at 20)), and the process is once ended. On the other hand, when the driver depresses the brake pedal 52 and stops the vehicle at, for example, an intersection or the like, and the automatic stop condition is satisfied (“YES” in S120), the driving time M
/ G control processing is stopped (S130). This running M
The / G control process is a process separately executed by the eco-run ECU 40, and is a process set to be executed in an automatic start process (FIG. 7) described later. Specifically, M /
In the G control process, the M / G 26 is set to the power generation mode during normal driving, and the M / G 26 is set during fuel cut during vehicle deceleration.
This is a process of setting the G26 to the regenerative mode to recover the traveling energy or assisting the rotation of the engine 2 immediately after returning from the fuel cut.

Next, engine stop processing is performed (S14).
0). That is, from the eco-run ECU 40 to the engine EC
When a fuel cut instruction is issued to U48, the engine ECU 48 stops fuel injection from the fuel injection valve 42 and further closes the throttle valve 46 fully. As a result, the combustion in the engine combustion chamber stops, and the operation of the engine 2 stops.

Next, execution of the engine stop M / G drive process (FIG. 5), which will be described later, is set (S150). Thus, the present process is temporarily ended. FIG. 5 shows a flowchart of the engine stop-time M / G drive process started by the eco-run ECU 40 by the execution of step S150. This process is a process repeatedly executed in a short period.

When the engine stop M / G drive process is started, first, it is determined whether or not an intake pressure reduction process end flag Xstop indicating that the intake pressure reduction process at the time of engine stop has ended is "OFF". (S210). Note that the intake pressure reduction processing end flag Xstop is determined by the eco-run ECU 4.
It is initially set to "OFF" when the power is turned on.

First, since Xstop = “OFF” (“YES” in S210), first, the engine ECU
48 is instructed to prohibit turning on the air conditioner (S
215). As a result, if the air conditioner is on, the engine ECU 48 shuts off the connection between the air conditioner compressor and the pulley 16 to stop driving the air conditioner.

Then, the crankshaft rotation processing (S22)
0) is executed. FIG. 6 shows details of the crankshaft rotation processing. In the crankshaft rotation process, first, the electromagnetic clutch 10a provided on the pulley 10 is turned on (S31).
0), the M / G 26 is set to the drive mode (S320). Note that the process of step S310 has already been performed by the electromagnetic clutch 10a.
If ON is maintained, the ON state is maintained. The same applies to other processes for turning on the electromagnetic clutch 10a.

Then, it is determined whether or not the rotational speed gradual decrease start flag Xdown is "OFF" (S330). It should be noted that the rotation speed gradual decrease start flag Xdown is
Is initially set to "OFF" when the power is turned on.

First, since Xdown = “OFF” (“YES” in S330), the target idle speed NEidl (for example, 600 rpm) is set as the target rotational speed NEt of the engine 2 (S340). Then, the output of the M / G 26 is controlled by the inverter 28 so that the engine speed NE becomes the target speed NEt (S35).
0). That is, the output of the M / G 26 causes the pulley 1
8, the crankshaft 2a of the engine 2 is rotated via the belt 14 and the pulley 10, and control for setting the engine 2 to a rotational speed equivalent to the idle rotation is started.

Next, it is determined whether or not the actual engine speed NE has reached the target engine speed NEt (S360). If the actual engine speed NE has not yet reached the target engine speed NEt ("NO" in S360), the present process is ended once.

Thereafter, by repeating steps S340 and S350, the engine speed NE is controlled to the target speed NEt by the output control of the M / G 26 (S350). Then, once the engine speed NE reaches the target speed N
If Et has been reached ("YES" in S360), it is then determined whether or not a reference time has elapsed since engine speed NE reached target speed NEt (S370). This reference time is, for example, 0.5 seconds. Until the reference time has elapsed ("NO" in S370), step S34.
0 and S350 are repeated.

If the reference time has elapsed after the engine 2 is forcibly maintained at the idling rotational speed by driving the M / G 26 ("YES" in S370), then the brake booster pressure sensor It is determined whether the brake booster pressure BBP detected at 56d has become equal to or less than the reference pressure Px (S380). This reference pressure Px
Represents a pressure that can sufficiently exert the boosting function of the brake pressing force even if the brake booster 56 immediately depresses the brake pedal 52 after the engine rotation stops.

If BBP> Px (“N” in S380)
O "), and then it is determined whether or not a limit time has elapsed since the engine speed NE reached the target speed NEt (S).
390). The limit time is, for example, 3 seconds. Until the limit time has elapsed (“NO” in S390), steps S340 and S350 are repeated. And BBP ≦ P
If x is reached (“YES” in S380), or if the limit time has elapsed (“YES” in S390), “ON” is set to the rotational speed gradual decrease start flag Xdown (S40).
0), the present process is temporarily terminated.

If BBP ≦ Px has already been reached when the reference time has elapsed (“YES” in S370), “ON” is immediately set in the rotational speed gradual decrease start flag Xdown (“YES” in S380). (S400) This process is once ended.

The reference time in step S370 described above is
This is a time provided to reduce the air pressure in the engine cylinder by forcibly rotating the crankshaft 2a at M / G 26 in the fully closed state of the throttle valve 46. This is to reduce the occurrence of vibration due to the pressure fluctuation in the cylinder when the rotation of the engine 2 is stopped. The reference time varies depending on the type of engine and the condition of the air conditioner and electric load up to immediately before.
The time required for the air pressure to be reduced to the air pressure that can surely reduce the generation of vibration is determined and set.

On the other hand, if the brake booster pressure BBP does not decrease to the reference pressure Px due to, for example, the driver operating the brake pedal 52, the limit time of step S390 is determined by the high voltage power supply battery 30. This time is set to avoid consumption of the charged amount.

In this way, the rotational speed gradual decrease start flag X
When down = “ON” (S400), in the next control cycle, “NO” is determined in step S330.
Then, it is determined whether or not there is a request for driving the power steering pump, that is, whether the power steering hydraulic pressure is high, such as during steering, or when the steering is held and stopped under a high load. Is determined (S410).

If there is no drive request for the power steering pump ("NO" in S410), then the target rotational speed NEt is calculated as shown in the following equation 1 (S420).

[0100]

NEt ← NEt−dNE (Equation 1) Here, the gradual change value dNE is a value for gradually lowering the target rotational speed NEt.

Then, it is determined whether the target rotational speed NEt has become equal to or less than the limit rotational speed NEs by the calculation of the above equation (S430). The limit rotational speed NEs is set as the rotational speed immediately before the engine 2 decreases to the resonance rotational speed. Here, for example, it is set to 400 rpm.

If NEt> NEs (“N” in S430)
O "), and then the output control of the M / G 26 is executed so that the engine speed NE becomes the target speed NEt (S44).
0). Then, the present process is temporarily ended.

Thereafter, by repeating step S420, if NEt ≦ NEs is satisfied ("YE" in S430).
S "), and then sets the value of the limit rotation speed NEs as the target rotation speed NEt (S445). Then, it is determined whether or not the engine speed NE has reached the target speed NEt (S45).
0). If the engine speed NE has not yet reached the target engine speed NEt ("NO" in S450), step S4
After the processing of step 40, the present processing is temporarily ended.

If the engine speed NE has reached the target engine speed NEt ("YES" in S450), "ON" is set to the intake pressure reduction processing end flag Xstop (S46).
0), the process is once ended.

In the state of NEt> NEs (S430)
("NO" in step S41), when it is determined in step S410 that there is a drive request for the power steering pump while the processes in steps S420 and S440 are repeated (S41).
0 and “YES”), only the step S440 is executed, and the present process is ended once. Thereby, step S420
Is not executed, the target rotational speed NEt is calculated in step S
As long as the determination at 410 is “YES”, the value of the target rotational speed NEt at that time is maintained. After that, when there is no drive request for the power steering pump (S410)
Then, the processing (S420, S430) for gradually decreasing the target rotational speed NEt to the limit rotational speed NEs is restarted.

After the target rotational speed NEt is gradually reduced to the limit rotational speed NEs in this way, Xstop = “O
N "(S460), so" NO "is determined in step S210 (FIG. 5) of the next control cycle. As a result, the instruction to permit the air conditioner to be turned on is issued by the engine ECU 48.
(S225). And then auxiliary equipment 22
Is determined (S230). Here, if there is a drive request for auxiliary equipment ("YE" in S230)
S "), the electromagnetic clutch 10a is turned off (S240),
The M / G 26 is set to the driving mode or is maintained in the driving mode (S250). Note that the process of step S240 includes a case where the electromagnetic clutch 10a is kept off if it is already off. The same applies to other processes for turning off the electromagnetic clutch 10a.

Then, the target rotational speed NMGt of the M / G 26
Then, a rotation speed NMGidl, which is a value obtained by converting the idle target rotation speed NEidl to the rotation speed of the M / G 26, is set (S260). The inverter 28 controls M / G 26 so that the actual rotational speed NMG of the M / G 26 becomes the target rotational speed NMGt.
/ G26 output control is performed (S270). Thus, the present process is once ended. On the other hand, if there is no drive request for the auxiliary devices ("NO" in S230), the function of M / G 26 is stopped (S280), and the present process is ended once.

After the engine speed NE is gradually decreased to the limit speed NEs in this way, the M / G 26 is turned off by turning off the electromagnetic clutch 10a (S240) or stopping the function of the M / G 26 (S280). The rotation of the crankshaft 2a by the driving force is stopped. Therefore, the engine rotation quickly stops after passing through the resonance rotation speed.

Incidentally, the function of the M / G 26 is stopped (S280).
After the rotation of the engine 2 is stopped by the
("YES" in S230),
When the M / G 26 is driven, the auxiliary equipment 22 is connected to the engine 2 via the pulley 18, the belt 14, and the pulley 16.
Can be rotated equivalent to the case where is in idle rotation. Therefore, even if the engine 2 is stopped,
Air conditioners and power steering can be driven as required. Then, in driving the M / G 26 when the engine operation is stopped (S240 to S270),
Since the electromagnetic clutch 10a is turned off, M /
Even if G26 is driven, the crankshaft 2a of the engine 2 does not rotate. Therefore, wasteful power consumption can be prevented and fuel efficiency can be improved.

Next, the automatic start process executed by the eco-run ECU 40 is shown in the flowchart of FIG. This process is a process repeatedly executed in a short period. When the automatic start process is started, first, an operation state for judging execution of automatic start is read (S510). here,
For example, the same as the data read in step S110 of the automatic stop processing (FIG. 4), the engine cooling water temperature THW, the state of the idle switch, the charged amounts of the batteries 30, 34,
The state of the brake switch 52a and the vehicle speed SPD etc.
M is read into the work area.

Next, it is determined from these operating states whether or not the automatic start condition is satisfied (S520). For example, under the condition that the engine is stopped by the automatic stop process, (1) the engine 2 has been warmed up and has not been overheated (the engine cooling water temperature THW is lower than the water temperature upper limit and the water temperature lower limit (Higher than the value), (2) the accelerator pedal is not depressed (idle switch is on),
(3) a state in which the charged amounts of the batteries 30 and 34 are at required levels, (4) a state in which the brake pedal 52 is depressed (the brake switch 52a is on), and (5) a state in which the vehicle is stopped. (Vehicle speed SPD is 0km /
h) If any one of the conditions (1) to (5) is not satisfied, it is determined that the automatic start condition is satisfied.

If the engine is not stopped by the automatic stop process, or if all of the above conditions (1) to (5) are satisfied even if the engine is stopped by the automatic stop process, the automatic start condition is not satisfied. (S52
0 and “NO”), the process is once ended.

If any one of the above conditions (1) to (5) is not satisfied in the engine stop state by the automatic stop processing, it is determined that the automatic start condition is satisfied (S520).
"YES"), and stops the above-described engine stop M / G drive process (FIG. 5) (S530). Then, execution of the M / G drive start / start process and the running M / G control process is set (S540). Here, the M / G drive start start process is as follows.
This is a process of starting the vehicle by driving the M / G 26 and instructing the engine ECU 48 to start the engine 2. The M / G control process during running is performed by rotating the M / G 26 with the output of the engine 2 to generate power when the vehicle is running normally, or by using the M / G 26 to control the running energy of the vehicle during fuel cut when the vehicle is decelerated. This is the process of collecting.

Next, the vibration reduction processing end flag Xstop is set to "OFF" (S550), and the rotational speed gradual decrease start flag Xdown is set to "OFF" (S560), and this processing is ended once.

Next, the braking control process executed by the VSC-ECU 50 is shown in FIG. This process is a process repeatedly executed in a short period. When this processing is started, first, it is determined whether or not the control cycle is immediately after the automatic stop condition is satisfied (S610). The automatic stop condition is the condition determined in step S120 of the above-described automatic stop process (FIG. 4), and it is determined from the communication data from the eco-run ECU 40 whether or not the automatic stop condition has just been satisfied. If it is not immediately after the automatic stop condition is satisfied ("N" in S610)
O "), then, it is determined whether or not the control cycle is immediately after the automatic start condition is satisfied (S620). The automatic start condition is the condition determined in step S520 of the above-described automatic start process (FIG. 7), and it is determined from the communication data from the eco-run ECU 40 whether or not the automatic start condition has just been satisfied. If it is not immediately after the automatic start condition is satisfied ("N" in S620
O "), braking control in normal time, that is, traction control, vehicle stability control, and antilock control are executed according to the driver's operation state, engine operation state, or vehicle running state (S630). Thus, the present process is once ended.

On the other hand, immediately after the automatic stop condition is satisfied ("YES" in S610), since the driving wheels are next, that is, in the first embodiment, the rear wheels are driven, the rear wheels RL,
The pressure control valve 81 on the RR side is driven to switch from the state of FIG. 3A to the state of FIG. As a result, the pressure control valve 81 is closed, and the main oil passage 75 between the master cylinder 56i and the brake cylinder 70 of each rear wheel RL, RR is shut off (S640). Thus, the present process is once ended.

Thereafter, when the automatic stop condition is not satisfied (“NO” in S610), it is then determined whether or not the control cycle is immediately after the automatic start condition is satisfied (S620). If the control cycle is immediately after the start condition is satisfied ("YES" in S620), the pressure control valves 81 on the rear wheels RL and RR are returned to the open state as shown in FIG. The main oil passage 75 between the cylinder 56i and the brake cylinder 70 of each rear wheel RL, RR is brought into a communicating state (S6).
50). Thus, the present process is once ended.

In the next control cycle in the braking control process (FIG. 8), “NO” in step S610 and step S6
Since "NO" is determined in step 20, the routine shifts to normal braking control (S630).

Next, FIG. 9 shows details of the engine rotation stop braking control process in which substantial processing is performed when automatic stop is performed. This process is a process executed by the VSC-ECU 50, and is a process repeatedly executed in a short cycle.

When the engine rotation stop braking control process is started, first, an intake pressure reduction process end flag Xstop
Is determined to be a control cycle immediately after switching from “OFF” to “ON” (S710). As described above, the intake pressure reduction processing end flag Xstop is a flag that is set by the processing on the eco-run ECU 40 side, and the contents thereof can be determined by communication from the eco-run ECU 40.

As described above, the intake pressure reduction processing end flag Xstop is set by executing step S460 of the crankshaft rotation processing (FIG. 6) executed by the eco-run ECU 40.
It can be switched from "OFF" to "ON". By switching the intake pressure reduction process end flag Xstop from “OFF” to “ON” in this manner, the M / G 26 stops rotating in the aforementioned engine stop M / G drive process (FIG. 5) (S280). ) Or electromagnetic clutch 10
a is turned off (S240). That is, after the intake pressure reduction processing end flag Xstop is switched from “OFF” to “ON”, the rotation of the crankshaft 2 a of the engine 2 performed by the driving force of the M / G 26 is stopped.

If the control cycle is not immediately after the intake pressure reduction processing end flag Xstop is switched from "OFF" to "ON"("NO" in S710), then whether the braking force reduction flag Xpd is "OFF" is determined. Is determined (S72).
0). The braking force reduction flag Xpd is a flag indicating that the braking force is being reduced to prevent vehicle vibration during automatic stop, and is initially set to “OFF” when the power of the VSC-ECU 50 is turned on. Flag.

The braking force reduction flag Xpd is "OFF"
If this is the case (“YES” in S720), the present process is temporarily terminated. On the other hand, in the control cycle immediately after the execution of step S460 of the crankshaft rotation processing (FIG. 6), the intake pressure reduction processing end flag Xstop is changed from “OFF” to “ON”.
(“YES” in S710), and then each of the pressure reducing valves 121 on the rear wheels RL and RR.
Is driven to open the valve (S730). At this time,
Step S640 of the braking control process (FIG. 8) has already been executed, the pressure control valves 81 on the rear wheels RL and RR are closed, and the master cylinder 56i and the rear wheels R
Main oil passage 75 between the left and right brake cylinders 70
Is in the shut-off state. Therefore, when the pressure reducing valve 121 is opened, the hydraulic oil in the brake cylinder 70 is supplied to the reservoir 119.
Is discharged into the reservoir chamber 125 of the brake cylinder 7
In the case of 0, the pressure is reduced and the braking force on the rear wheels RL and RR is reduced.
In the first embodiment, the braking force on the rear wheels RL and RR is “0”.
It is said.

Next, the braking force reduction flag Xpd is set to "ON".
Is set to (S740). And the engine ECU 4
It is determined whether or not the engine speed NE obtained from step 8 is equal to or less than the rotation stop reference value NEstop (S750).
The rotation stop reference value NEstop is a determination value for determining that the crankshaft 2a of the engine 2 has stopped, and for example, a value of “0 rpm” is set.

If NE> NEstop and the crankshaft 2a of the engine 2 has not stopped ("NO" in S750), the present process is temporarily terminated. In the next control cycle, the intake pressure reduction processing end flag Xstop is “ON” as in the previous control cycle (S710).
Is "NO"), and then the braking force reduction flag Xpd is set to "OF".
F "(S720), but since Xpd =" ON "in the immediately preceding control cycle (" NO "in S720), the engine speed NE becomes the rotation stop reference value NE.
It is determined whether the value is equal to or less than stop (S750). NE>
If the state of NEstop is continued (“N” in S750)
O "), the processing is once ended as it is.

Thereafter, NE is generated by the inertial rotation of the engine 2.
As long as> NEstop ("NO" in S750), this process is temporarily terminated as it is, so that the brake cylinder 7
The pressure 0 remains depressurized, and the reduced state of the braking force on the rear wheels RL and RR continues.

When the rotation of the crankshaft 2a of the engine 2 is stopped and NE ≦ NEstop is satisfied (“YE” in S750).
S "), and then return the pressure reducing valves 121 on the rear wheels RL and RR to the closed state (S760). And self-supply pump motor 8
6 is rotated and the reservoir 119 is operated by the self-supply pump 85.
The hydraulic oil discharged into the reservoir chamber 125 is returned to the brake cylinder 70 of the rear wheels RL and RR again.
The braking forces of L and RR are restored (S770).

Next, the braking force reduction flag Xpd is set to "OF".
F "(S780), and the process ends once.
Thus, in the next control cycle, step S710
"NO" at step S720 and "YES" at step S720.
Is determined, the substantial processing in the engine rotation stop braking control processing is stopped.

An example of the processing executed as described above is shown in the timing chart of FIG. As shown by the solid line,
Before time t0, the engine 2 is operated at an idle speed corresponding to the load state at that time by the idle speed control executed by the engine ECU 48 after the vehicle stops. When the automatic stop condition is satisfied at time t0, the operation of the engine 2 is stopped by stopping the fuel injection from the fuel injection valve 42. The engine stop M / G drive process (FIG. 5) and the crankshaft rotation process (FIG. 6)
The M / G 26 is driven to set the engine target rotational speed NEt to the idle target rotational speed NEidl (= 600 rpm), and this rotational state continues for the reference time. This M / G2
6, when the engine 2 is forcibly rotated, the throttle valve 46 is in the fully closed state, so that the air pressure in the cylinder becomes sufficiently low, and the generation of vibrations due to the pressure fluctuation in the cylinder when the engine rotation is stopped can be reduced.

Then, at time t1 after the reference time, since the brake booster pressure BBP has already become equal to or lower than the reference pressure, the engine target speed NEt is gradually reduced thereafter. Therefore, the creep force transmitted to the wheel via the torque converter 4 and the A / T 6 in the non-lockup state gradually decreases.

When the target engine speed NEt reaches the limit engine speed NEs (= 400 rpm) at time t2, if there is no drive request for the auxiliary equipment 22, the drive of the M / G 26 is stopped. If there is a drive request, the electromagnetic clutch 10a is turned off. Therefore, the rotation of the crankshaft 2a of the engine 2 by the driving force of the M / G 26 ends. Thus, the rotation of the engine 2 stops.

At time t2 when the engine rotation is stopped by the M / G 26, the braking force on the rear wheel is reduced to "0" by the processing of the engine rotation stop braking control processing (FIG. 9). As described above, the torque transmitted from the crankshaft 2a side of the engine 2 to the power transmission system rapidly disappears in a state where the braking force on the rear wheel is lost. Therefore, the vibration caused by the torque fluctuation due to the rapid disappearance of the torque is transmitted to the wheels via the crankshaft 2a, the torque converter 4, the A / T 6, and the output shaft 6a,
It is absorbed by the rubber tire part of the wheel.

If the engine rotation is stopped at time t3, the braking force on the rear wheels is immediately returned to the original state by the processing of the engine rotation stop braking control processing (FIG. 9). In the configuration of the first embodiment described above, the automatic stop process (FIG. 4), the engine stop M / G drive process (FIG. 5), and the crankshaft rotation process (FIG. 6) include processes as drive source drive stop means. The engine rotation stop braking control process (FIG. 9) corresponds to a process as a braking force adjusting unit.

According to the first embodiment described above, the following effects can be obtained. (I). When stopping the rotation of the crankshaft 2a by the driving force of the M / G 26, if the braking force acting on the rear wheels RL, RR is temporarily reduced, the torque fluctuation generated when the driving by the M / G 26 is stopped is reduced by the rear wheel RL. , RR to the rubber tire portion. As a result, vehicle vibration due to torque fluctuation can be reduced by the vibration damping function of the rubber tire.

Since the reduction of the braking force may be temporary when the driving of the M / G 26 is stopped, the braking force is returned to the original braking force immediately after the rotation of the crankshaft 2a is stopped. The braking force is maintained for the front wheels FL and FR. Therefore, there is no problem in the braking performance of the vehicle. Moreover, A
Since the transmission of torque fluctuation is not prevented by, for example, shutting off the power transmission system such as / T6, no shock is generated when the engine is started.

(B). Before the braking force of the rear wheels RL, RR is temporarily reduced, the engine is rotated by driving the M / G 26, and a process of reducing torque fluctuation due to an increase in the in-cylinder negative pressure of the engine 2 is also performed. Further, the crankshaft 2a
The rotation speed is also stopped after the rotation speed is reduced to some extent. From this, it is possible to produce a higher effect in reducing vehicle vibration.

(C). The rotation of the crankshaft 2a is stopped before the engine 2 reaches a resonance rotation speed region that causes resonance. Therefore, when the engine speed NE passes through the resonance speed region, the period during which the braking force of the rear wheels RL and RR is reduced is reduced, and vehicle vibration caused by resonance is also reduced. Therefore, a higher effect can be produced in reducing vehicle vibration.

(D). Since the braking force is reduced by the rear wheels RL and RR, which are drive wheels, vibrations caused by torque fluctuations transmitted from the power transmission system to the rear wheels RL and RR are reduced.
The vibration can be efficiently damped by the vibration damping function of the rear wheels RL and RR.

(E). In the first embodiment, the braking force is reduced during the automatic stop processing. Such a process of automatically stopping the engine rotation is an unintended stop by the driver, so that the occupant is likely to feel uncomfortable due to the vehicle vibration. However, in the first embodiment, the process is temporarily stopped during the automatic stop process. Since the power is reduced to reduce the vehicle vibration, the effect of preventing the driver from feeling uncomfortable is remarkable.

[Embodiment 2] Embodiment 2 is different from Embodiment 1 in that a braking control process at the time of engine drive stop shown in FIG. 11 is further executed.
This process is a process executed by the VSC-ECU 50, and is a process repeatedly executed in a short cycle.

The braking control process at the time of engine stop will be described. When this processing is started, first, in step S140 of the automatic stop processing (FIG. 4), the fuel injection valve 4
It is determined whether or not the current control cycle is immediately after the fuel injection stop of No. 2 is started (S810). If it is not the control cycle immediately after the start of the fuel injection stop ("NO" in S810), it is then determined whether or not the braking force reduction flag Xpf is "OFF" (S
820). The braking force reduction flag Xpf is a flag indicating that the braking force is being reduced to prevent vehicle vibration when the engine is stopped, and VSC-
This flag is initially set to “OFF” when the power of the ECU 50 is turned on.

If the braking force reduction flag Xpf is "OFF"("YES" in S820), then the timer counter T
"0" is set to p (S825), and this process is once ended.

Step S140 of the automatic stop processing (FIG. 4)
Is executed immediately after the start of the fuel injection stop ("YES" in S810), then the rear wheel R
Each of the pressure reducing valves 121 on the L and RR sides is driven to an open state,
The hydraulic oil in the brake cylinder 70 is released into the reservoir chamber 125 of the reservoir 119 (S830). As a result, the brake cylinder 70 is depressurized and the rear wheels RL, RR
Side braking force is reduced. In the second embodiment, the rear wheels RL,
The braking force on the RR side is set to “0”.

Next, the braking force reduction flag Xpf is turned "ON".
(S840), and then the value of the timer counter Tp is incremented (S850). Then, it is determined whether the value of the timer counter Tp is equal to or greater than the reference value Tstop (S860). This reference value Tstop includes:
A value corresponding to a period until the torque fluctuation which may occur when the driving of the engine 2 is switched to the driving of the M / G 26 is completed and the torque of the crankshaft 2a is stabilized is set.

Tp <Tstop, that is, the rear wheels RL,
After executing the RR braking force reduction, the reference value Tsto
If the period corresponding to p has not elapsed (S860).
, "NO"), and the process is once ended as it is.

In the next control cycle, the control cycle is not immediately after the start of the fuel injection stop of the fuel injection valve 42 ("NO" in S810), and then the braking force reduction flag Xpf
Is determined to be “OFF” (S820), since Xpf = “ON” in the immediately preceding control cycle (S8).
20 ("NO"), the timer counter Tp is incremented (S850). Then, it is determined whether the value of the timer counter Tp is equal to or more than the reference value Tstop (S86).
0). In the beginning, since Tp <Tstop ("NO" in S860), the present process is temporarily terminated as it is.

Thereafter, as long as Tp <Tstop (S8
60, “NO”), step S810 (“NO”), S
820 ("NO"), S850, S860 ("NO")
Is repeated, the brake cylinder 70 remains depressurized, and the state of reduction of the braking force on the rear wheels RL and RR continues.

The increment of the timer counter Tp (S850) is repeated, so that Tp ≧ T
When the stop is reached ("YES" in S860), the pressure reducing valves 121 on the rear wheels RL and RR are returned to the closed state (S
870). Then, the self-supply pump motor 86 is rotated,
The reservoir chamber 12 of the reservoir 119 by the self-supply pump 85
The hydraulic oil discharged to the rear wheel 5 is returned to the brake cylinder 70 of the rear wheels RL, RR again, and the braking force of the rear wheels RL, RR is restored (S880).

Next, the braking force reduction flag Xpf is set to "OF".
F "(S890), and the process is once terminated.
As a result, in the next control cycle, step S810
"NO" at step S820, and "YES" at step S820.
Is determined, the timer counter Tp is returned to “0” (S825). In this manner, the substantial processing of the engine drive stop braking control processing (FIG. 11) is stopped.

FIG. 1 shows an example of the control according to the second embodiment.
2 is shown in the timing chart. That is, at time t10
When the fuel injection is stopped to shift to the engine rotation by the M / G 26, the braking force of the rear wheels RL and RR is immediately reduced by the processing of the engine drive stop-time braking control processing (FIG. 11). Thereafter, during a period corresponding to the reference value Tstop, the braking force reduction state of the rear wheels RL and RR continues. Then, when the period corresponding to the reference value Tstop ends at time t11, the braking forces of the rear wheels RL and RR return.

When the drive of the M / G 26 is stopped at time t12, the rear wheel RL, RL, RL, is again driven by the engine rotation stop braking control process (FIG. 9) described in the first embodiment. The RR braking force is reduced. Then, at time t13 when the engine speed NE becomes equal to or less than the rotation stop reference value NEstop, the braking forces of the rear wheels RL and RR are restored again.

In the configuration of the second embodiment described above, the automatic stop processing (FIG. 4), the engine stop M / G drive processing (FIG. 5) and the crankshaft rotation processing (FIG. 6) serve as drive source drive stopping means. In the processing, the braking control processing when the engine is stopped (FIG. 9) and the braking control processing when the engine is stopped (FIG. 11) correspond to the processing as the braking force adjusting means.

According to the second embodiment described above, the following effects can be obtained. (I). The effects (a) to (e) of the first embodiment can be obtained. (B). It is also conceivable that the driving of the engine 2 is stopped and the vehicle fluctuates when the M / G 26 shifts to the rotation of the crankshaft 2a to cause vehicle vibration. Therefore, in the second embodiment, even when the fuel injection to the engine 2 is stopped and the driving of the engine 2 is stopped,
The braking force is temporarily reduced. As a result, even if the torque fluctuates when the driving of the engine 2 is stopped, vehicle vibration can be prevented, and the driver does not feel uncomfortable. Although the braking force is reduced twice, both are extremely short and the front wheel F
Since the braking force is maintained for L and FR, there is substantially no problem in braking performance.

[Third Embodiment] In the third embodiment, in the configuration described in the first embodiment, the engine drive / rotation stop shown in FIG. 13 is performed instead of the engine rotation stop braking control process (FIG. 9). The difference is that the time braking control process is executed. The other configuration is the same as that of the first embodiment unless otherwise specified.

A description will now be given of the braking control processing at the time of engine drive / rotation stop. This process is a process repeatedly executed by the VSC-ECU 50 in a short period. When this processing is started, first, in step S of the automatic stop processing (FIG. 4)
By executing 140, it is determined whether or not the control cycle is immediately after the start of the fuel injection stop (S910). If the control cycle is not immediately after the start of the fuel injection stop ("N" in S910)
O)), it is then determined whether or not the braking force reduction flag Xpg is "OFF" (S920). Braking force reduction flag Xpg
Is a flag indicating that the braking force is being reduced to prevent vehicle vibration during automatic stop, and is a flag that is initially set to “OFF” when the power of the VSC-ECU 50 is turned on.

If the braking force reduction flag Xpg is "OFF"("YES" in S920), the present process is ended once. In the control cycle immediately after the execution of step S140 of the automatic stop processing (FIG. 4), the control cycle is immediately after the start of the fuel injection stop ("YES" in S910), and then each of the rear wheels RL, RR side The pressure reducing valve 121 is driven to open the valve, and the operating oil in the brake cylinder 70 is supplied to the reservoir 119.
(S930). As a result, the brake cylinder 70 is depressurized and the rear wheels RL, R
The braking force on the R side decreases.

Next, the braking force reduction flag Xpg is set to "ON".
Is set to (S940). And the engine ECU 4
It is determined whether or not the engine speed NE obtained from step 8 is equal to or less than the rotation stop reference value NEstop (S950).
This rotation stop reference value NEstop is a value for determining that the crankshaft 2a of the engine 2 has stopped,
For example, a value of “0 rpm” is set.

If NE> NEstop and the crankshaft 2a of the engine 2 has not stopped ("NO" in S950), the present process is temporarily terminated. In the next control cycle, since it is not the control cycle immediately after the start of the fuel injection stop ("NO" in S910), it is next determined whether or not the braking force reduction flag Xpg is "OFF" (S9).
20), since Xpg = “ON” in the immediately preceding control cycle (“NO” in S920), the engine speed NE
Is smaller than or equal to the rotation stop reference value NEstop (S950). Also at this time, if NE> NEstop ("NO" in S950), the present process is temporarily ended as it is.

Subsequently, the engine 2 driven by the M / G 26
NE> N due to the rotation of the engine or the inertial rotation of the engine 2
As long as the status is "Estop"("NO" in S950), the present process is temporarily ended as it is. Therefore, the brake cylinder 70 is kept depressurized, and the reduced braking force on the rear wheels RL and RR continues.

When the rotation of the crankshaft 2a of the engine 2 stops and NE ≦ NEstop is satisfied (“YE” in S950).
S "), and then return the pressure reducing valves 121 on the rear wheels RL and RR to the closed state (S960). And self-supply pump motor 8
6 is rotated and the reservoir 119 is operated by the self-supply pump 85.
The hydraulic oil discharged into the reservoir chamber 125 is returned to the brake cylinder 70 of the rear wheels RL and RR again.
The braking forces of L and RR are restored (S970).

Next, the braking force reduction flag Xpg is set to "OF".
F "(S980), and the process ends once.
As a result, in the next control cycle, step S910
"NO" at step S920, and "YES" at step S920.
Thus, the substantial processing in the engine drive / rotation stop braking control processing (FIG. 13) is stopped.

An example of the control according to the third embodiment is shown in a timing chart of FIG. That is, when the fuel injection is stopped at time t20 and the engine rotation is started by the M / G 26, the engine drive / rotation stop braking control process (FIG. 1)
According to 3), the braking force of the rear wheels RL and RR is immediately reduced. Thereafter, the braking force reduction state of the rear wheels RL and RR continues until the driving of the M / G 26 is stopped and the engine speed NE becomes equal to or less than the rotation stop reference value NEstop. When the engine speed NE becomes equal to or lower than the rotation stop reference value NEstop at time t21, the braking forces of the rear wheels RL and RR are restored again.

In the structure of the third embodiment described above, the automatic stop processing (FIG. 4), the engine stop M / G drive processing (FIG. 5), and the crankshaft rotation processing (FIG. 6) serve as drive source drive stop means. In the process, the engine drive / rotation stop braking control process (FIG. 13) corresponds to a process as a braking force adjusting unit.

According to the third embodiment described above, the following effects can be obtained. (I). The effects (a) to (e) of the first embodiment can be obtained. (B). In the third embodiment, the braking force is temporarily reduced during the period from when the fuel injection is stopped to the engine 2 to when the rotation of the crankshaft 2a is stopped. As a result, even when the torque fluctuates from when the driving of the engine 2 is stopped to when the M / G 26 is stopped, vehicle vibration can be prevented, and the driver does not feel uncomfortable. It should be noted that the period from the time when the fuel injection is stopped to the engine 2 to the time when the rotation of the crankshaft 2a is stopped is short.
Since the braking force of FR is maintained, even if the braking force of the rear wheels RL and RR is reduced during this time, substantially no problem occurs in the braking performance.

[Other Embodiments] In the first embodiment, the crankshaft 2a of the engine 2 is controlled by the M / G 26 immediately after the driving of the engine 2 is stopped.
, The reduction of the braking force of the rear wheels RL, RR was performed when the rotation of the engine 2 by the M / G 26 was stopped. However, in the case of a system in which the rotation of the engine 2 is not performed by the M / G 26 when the driving of the engine is stopped, step S1 of the automatic stopping process (FIG. 4) is performed.
Immediately after the execution of step 40, the rotation of the crankshaft 2a of the engine 2 is stopped. Therefore, in the case of the system in which the engine rotation by the M / G 26 is not performed, the braking control process at the time of the engine rotation stop (FIG. 9) is performed after the execution of the step S140 of the automatic stop process (FIG. 4) and the step S730. To S770. FIG. 15 shows an example of the control in this case. That is, the time t
When the fuel injection is stopped at 30 and the engine 2 is automatically stopped, the braking force of the rear wheels RL, RR is immediately reduced.
When the engine speed NE becomes equal to or less than the rotation stop reference value NEstop at time t31, the rear wheels RL, R
The braking force of R returns. By doing so, vehicle vibration due to torque fluctuation during automatic stop is reduced,
It is possible to prevent the driver from feeling uncomfortable.

In the first embodiment, the return of the braking force is
This is executed when the rotation of the crankshaft 2a of the engine 2 is stopped.
The braking force may be restored when the reference time has elapsed after the time immediately after the op switches from “OFF” to “ON”. The same applies to the second braking force return in the second embodiment. FIG.
The same applies to the example shown in FIG.

In the above embodiments, the braking force of the rear wheels RL, RR is reduced in order to prevent vehicle vibration. However, instead of the rear wheels RL, RR, the braking force of the front wheels FL, FR is reduced. It may be reduced. The torque fluctuation of the engine 2 is not only transmitted from the power transmission system to the rear wheels RL and RR as drive wheels, but also transmitted directly or indirectly from the engine 2 to the vehicle body without passing through the power transmission system. As a result, torque fluctuations of the engine 2 are transmitted in a form of vibration from the vehicle body to the front wheels FL and FR that are driven wheels. Therefore, even when the braking force reduction target is the front wheels FL and FR, the front wheels F
Vehicle vibration can be reduced by the vibration damping function of L and FR.

Also, the front wheels FL, F together with the rear wheels RL, RR
R may also reduce the braking force at the same time. As described above, by temporarily reducing the braking force of both the driving wheel and the driven wheel, the vibration damping function is enhanced, and the vehicle vibration can be more effectively reduced. In addition, since such a reduction in the braking force is temporary, there is no problem in the braking performance.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a vehicle internal combustion engine and a control device thereof according to a first embodiment.

FIG. 2 is a hydraulic circuit configuration diagram of a braking mechanism according to the first embodiment.

FIG. 3 is a configuration explanatory view of a pressure control valve used in the hydraulic circuit.

FIG. 4 is a flowchart of an automatic stop process executed by the eco-run ECU according to the first embodiment.

FIG. 5 is a flowchart of an engine stop M / G drive process executed by the eco-run ECU of the first embodiment.

FIG. 6 is a flowchart of a crankshaft rotation process executed by the eco-run ECU of the first embodiment.

FIG. 7 is a flowchart of an automatic start process executed by the eco-run ECU of the first embodiment.

FIG. 8 is a flowchart of a braking control process executed by the VSC-ECU according to the first embodiment.

FIG. 9 is a flowchart of an engine rotation stop braking control process executed by the VSC-ECU according to the first embodiment;

FIG. 10 is a timing chart showing an example of control according to the first embodiment.

FIG. 11 is a flowchart of an engine drive stop braking control process executed by the VSC-ECU according to the second embodiment.

FIG. 12 is a timing chart illustrating an example of control according to the second embodiment.

FIG. 13 is a flowchart of an engine drive / rotation stop braking control process executed by the VSC-ECU according to the third embodiment;

FIG. 14 is a timing chart showing an example of control according to the third embodiment.

FIG. 15 is a timing chart showing an example of control in a modification of the first embodiment.

[Explanation of symbols]

2 ... Engine, 2a ... Crankshaft, 2b ... Intake pipe, 2c
... Surge tank, 4 ... Torque converter, 6 ... A / T,
6a: output shaft, 10: pulley, 10a: electromagnetic clutch,
14 ... belt, 16, 18 ... pulley, 22 ... accessories, 2
6 M / G, 28 inverter, 30 high voltage power supply battery, 32 DC / DC converter, 34 low voltage power supply battery, 36 starter, 38 electric hydraulic pump,
40: Eco-run ECU, 42: Fuel injection valve, 44: Electric motor, 46: Throttle valve, 46a: Throttle opening sensor, 48: Engine ECU, 50: VSC-E
CU, 52: brake pedal, 52a: brake switch, 56: brake booster, 56a: diaphragm,
56b: 1st pressure chamber, 56c ... 2nd pressure chamber, 56d ...
Brake booster pressure sensor, 56e ... check valve, 5
6f: negative pressure control valve, 56g: spring, 56h ...
Push rod, 56i Master cylinder, 56j Input rod, 64 Brake, 66 Brake cylinder, 68 Brake, 70 Brake cylinder, 74,
75 ... main oil passage, 76, 77 ... trunk passage, 78, 79 ...
Branch passage, 80, 81: Pressure control valve, 82, 83: Pump passage, 84, 85: Self-supply pump, 86: Self-supply pump motor, 90: Valve body, 92: Valve seat, 94: Solenoid, 9
6 ... Spring, 98 ... Armature, 102,103
... bypass passage, 104, 105 ... bypass valve, 11
0, 111: holding valve, 112, 113: bypass passage,
114, 115 ... bypass valve, 116, 117 ... reservoir passage, 116, 117 ... reservoir passage, 118, 11
9 ... Reservoir, 120,121 ... Reducing valve, 122,12
3 ... Reservoir piston, 124, 125 ... Reservoir chamber,
126, 127 ... spring, 130, 131 ... suction passage, 132, 133 ... discharge passage, 134, 135 ... suction valve, 136, 137 ... discharge valve, 138, 139 ... damper chamber, 138a, 139a ... orifice, 140, 141
... supply passages, 142, 143, inflow control valves, 144, 1
45: check valve, 146: master reservoir, 150: auxiliary supply passage, 152, 153: auxiliary inflow control valve, 154: check valve, 202: master cylinder oil pressure sensor, 204: wheel speed sensor.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 29/02 341 F02D 29/02 341 F02N 15/00 F02N 15/00 E F16F 15/02 ZHV F16F 15 / 02 ZHVB F term (reference) 3D046 BB02 BB07 CC02 EE01 GG02 HH02 HH08 HH16 HH17 HH36 LL10 LL23 LL37 3G092 AA01 AC03 DF08 DG08 DG09 EA02 DA28 FA14 GA10 GB08 GB10 HE08Z HF08 HF03 A03 DA03 FB02 3J048 AA10 AD01 AD20 BF12 CB19 CB30 EA36

Claims (20)

[Claims] A vehicle vibration reducing method for reducing vehicle vibration generated when the driving force is stopped in a state where a driving force is transmitted to a power transmission system to wheels and a braking force is acting on the wheels. A vehicle vibration reduction method characterized by reducing vehicle vibration by temporarily reducing a braking force of a wheel when the driving force is stopped. 2. A structure according to claim 1, wherein a driving force is transmitted to said power transmission system by an internal combustion engine.
The driving force is stopped by stopping the driving of the internal combustion engine. 3. The drive power transmission system according to claim 1, wherein the drive power is transmitted to the power transmission system by another drive source that is rotating the internal combustion engine that is already stopped. Stopping the driving of the other driving source. 4. A vehicle vibration reducing method according to claim 3, wherein the rotation of the internal combustion engine by the other drive source is a process temporarily executed immediately after the stop of the driving of the internal combustion engine. . 5. The method according to claim 4, wherein the braking force is reduced during a period from when the driving of the internal combustion engine is stopped to when the driving of the other driving source is stopped. 6. The vehicle according to claim 4, wherein the braking force is temporarily reduced when the driving of the internal combustion engine is stopped and when the driving of the other drive source is stopped. Vibration reduction method. 7. A vehicle vibration system according to claim 2, wherein the drive stop of the internal combustion engine is a process automatically executed when an internal combustion engine stop condition is satisfied. Reduction method. 8. A vehicle vibration reduction method according to claim 1, wherein the braking force reduction target is a drive wheel. 9. A vehicle vibration reduction method according to claim 1, wherein the braking force reduction target is a driven wheel. 10. A vehicle vibration reducing method according to claim 1, wherein the braking force is reduced for driving wheels and driven wheels. 11. When the driving force from the driving source is stopped in a state where the driving force is transmitted from the driving source to the power transmission system to the wheels and the braking force is applied to the wheels by the braking mechanism. A vehicle vibration reduction device that reduces vehicle vibration, comprising: a drive source drive stop unit that stops driving of the drive source; and a braking force on a wheel when the drive of the drive source is stopped by the drive source drive stop unit. And a braking force adjusting means for adjusting the braking mechanism so as to temporarily reduce the vehicle vibration. 12. A vehicle vibration reducing device according to claim 11, wherein said drive source is an internal combustion engine. 13. A vehicle vibration reducing apparatus according to claim 11, wherein said drive source is another drive source that is rotating an internal combustion engine that has already been stopped. 14. A drive system according to claim 13, wherein said drive source drive stopping means stops the drive of the internal combustion engine, and temporarily stops the drive of the internal combustion engine by the other drive source immediately after the stop of the drive of the internal combustion engine. A vehicle vibration reduction device, wherein the rotation of the internal combustion engine is stopped by rotating and then stopping the driving of the other drive source. 15. The structure according to claim 14, wherein said braking force adjusting means reduces the braking force during a period from when the driving of the internal combustion engine is stopped to when the driving of the other driving source is stopped. Vehicle vibration reducing device. 16. The braking force adjusting means according to claim 14, wherein the braking force adjusting means temporarily reduces the braking force when the driving of the internal combustion engine is stopped and when the driving of the other driving source is stopped. A vehicle vibration reduction device characterized by performing. 17. The drive system according to claim 12, wherein said drive source drive stopping means automatically stops driving the internal combustion engine when an internal combustion engine stop condition is satisfied. Vehicle vibration reduction device. 18. A vehicle according to claim 11, wherein said braking force adjusting means adjusts said braking mechanism so as to temporarily reduce a braking force on driving wheels. Vibration reduction device. 19. A vehicle according to claim 11, wherein said braking force adjusting means adjusts said braking mechanism so as to temporarily reduce a braking force on a driven wheel. Vibration reduction device. 20. A structure according to claim 11, wherein said braking force adjusting means adjusts said braking mechanism so as to temporarily reduce a braking force on a driving wheel and a driven wheel. Vehicle vibration reducing device.