JP3449219B2 - Braking force control device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a braking force control device for controlling a working fluid pressure to a braking cylinder of each wheel to an optimum state to prevent wheel locking, and particularly, an engine and a motor generator are provided together. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a braking force control device applied to a vehicle such as a parallel hybrid vehicle that controls a braking force by a working fluid pressure applied to a braking cylinder of each wheel when regenerating a motor generator during braking, for example.

[0002]

2. Description of the Related Art In a vehicle which obtains a driving force from a motor generator as described above, at the time of braking, the wheels are braked by applying hydraulic pressure to a hydraulic brake as is adopted in a general engine automobile, and at the same time, as an electric motor. Is used as a generator, that is, regenerative operation is performed, and a part of the braking force is obtained by the regenerative torque of the motor generator. Then, the battery is charged with the electric power regenerated by the motor generator.

By the way, an antilock brake control device is known as a device for controlling the braking of an automobile. This anti-lock brake control device is a device that performs braking control so that the wheels do not lock even when sudden braking is applied on a slippery road surface such as a snow road.

As a vehicle equipped with a motor generator equipped with such an anti-lock brake control device, there is, for example, the one described in JP-A-6-219259. In the anti-lock brake control device described in this publication, when the wheels are about to lock, either the braking force by the hydraulic brake or the electric braking force by the regenerative torque of the motor generator, for example, the braking force by the hydraulic brake is anti-locked. When lock brake control is performed and the motor generator is in regenerative operation, the braking force is excessive, so it does not hinder the wheel speed recovery when the anti-lock brake control device reduces the working fluid pressure. As described above, the regenerative operation amount of the motor generator is reduced to reduce the applied electric braking force.

[0005]

In contrast to such an anti-lock brake control device, in the control means that controls the regenerative operation of the motor generator, the state in which the motor generator is in the regenerative operation is a situation of excessive braking force, and For example, the regenerative operation of the motor generator is stopped and the application of the electric braking force is stopped so that the lock brake control device does not hinder the recovery of the wheel speed when the working fluid pressure is reduced. Then, when the motor generator is regeneratively operated, the working fluid pressure to the braking cylinder of the predetermined wheel is regeneratively cooperatively controlled. This regenerative cooperative control is, for example, detecting the amount of depression of the brake pedal by the master cylinder pressure, and subtracting the braking force by the regenerative torque of the motor generator from the braking force corresponding to this master cylinder pressure, the braking of each wheel. The working fluid pressure is controlled to be reduced so as to be exerted by the working cylinder.

When this regenerative cooperative control is applied to the antilock brake control device described in the above-mentioned prior publication, the electric braking force due to the regenerative operation of the motor generator is reduced with the start of the antilock brake control, and then this control is performed. Therefore, the pressure reduction amount of the regenerative coordinated pressure reduction by the regenerative coordinated control is reduced. It will be set based on the parameter for calculating the pressure reduction amount such as the wheel speed or its changing speed, that is, the supply pressure to the wheel cylinder is increased by reducing the pressure reduction amount of the regenerative coordinated pressure reduction. As a result, the pressure reduction tends to be insufficient and the controllability of the anti-lock brake control deteriorates. There is a problem.

Further, depending on the running condition, a sharp change in the braking force affects the running state of the vehicle, so that the application of the electric braking force is not stopped at the time when the antilock brake control is started, but for example, There is a case where the electric braking force is reduced by the inclination, and in this case, if the regenerative coordinated pressure reduction is stopped at the same time as the start of the antilock brake control, the supply pressure to the wheel cylinders will be increased accordingly. Therefore, there is a problem that the controllability of the antilock brake control deteriorates as in the above case because the braking force tends to be excessive.

Therefore, the present invention has been made by paying attention to the above-mentioned conventional problems, and suspends the regenerative cooperative control for reducing the working fluid pressure to the braking cylinder according to the electric braking force. In this case, it is an object of the present invention to provide a braking force control device capable of avoiding deterioration of controllability of antilock brake control.

[0009]

In order to achieve the above object, a braking force control apparatus according to claim 1 of the present invention comprises an electric braking means for applying an electric braking force to a predetermined wheel. , A fluid pressure braking means for applying a braking force to the wheel by a working fluid pressure to the braking cylinder of each wheel, and a working fluid pressure to the braking cylinder of each wheel individually according to the locked state of each wheel and antilock brake control means for controlling the electrical braking force equivalent fluid pressure component of the electric braking means the working fluid pressure in the to the brake cylinder when the braking force of the electric braking means has been granted comprising a work <br/> dynamic fluid pressure control means for reducing, the said electric braking means,
A braking force control device adapted to stop or reduce the application of the electric braking force when the anti-lock brake control means controls the working fluid pressure to the braking cylinder. The anti-lock when the lock brake control means controls the working fluid pressure to be reduced.
It is characterized in that a reduced pressure amount correction means for correcting the reduced pressure amount by the brake control means according to the electric braking force is provided.

A braking force control device according to a second aspect of the present invention is
The decompression amount correction means corrects the decompression amount of the working fluid pressure at the time of the first decompression control after the antilock brake control by the antilock brake control means is started according to the electric braking force at the start of the antilock brake control. The feature is that it is designed to do.

Further, in the braking force control device according to a third aspect of the present invention, the decompression amount correcting means estimates the electric braking force from the amount of decrease in the working fluid pressure by the working fluid pressure control means. It is characterized by being.

[0012]

According to the braking force control device of the first aspect of the present invention, when the anti-lock brake control means controls the pressure reduction of the working fluid pressure to the braking cylinder, the pressure reduction amount correction means controls the anti-lock brake control means. It is corrected according to the electrical braking force to pressure reduction by, because performing decompression control based on the corrected pressure reduction amount, an anti-lock brake control
When the pressure reduction control by the control means is started, the working fluid pressure control means reduces the working fluid pressure by an amount equivalent to the electric braking force.
Even if the total braking force equivalent to the electric braking force increases due to the stoppage or decrease in the amount of stoppage , the increased pressure due to this increase can be corrected as the reduced pressure equivalent to the electric braking force. Therefore, it is possible to prevent the controllability of the antilock brake control unit from being lowered due to excessive braking force due to the electric braking force.

According to a second aspect of the present invention, in the braking force control device, the amount of reduction of the working fluid pressure at the first pressure reduction control after the start of the antilock brake control is determined by the electric braking force at the start of the antilock brake control. It will be corrected according to
The influence of the electric braking force is eliminated by the first pressure reduction control, and the proper antilock brake control can be started at an earlier point.

Further, in the braking force control device according to the third aspect of the present invention, since the pressure reducing amount correcting means estimates the electric braking force from the amount of decrease in the working fluid pressure by the working fluid pressure controlling means, the electric braking force is controlled. The power can be easily estimated.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an example in which the braking force control device according to the present invention is applied to a so-called FF type parallel hybrid vehicle.

EG is a gasoline engine, and this engine EG is connected to a continuously variable transmission CVT via a clutch CL such as an electromagnetic powder clutch. During the connection, for example, a three-phase induction motor / generator. An AC motor generator MG including the above components is inserted. The output shaft of the continuously variable transmission CVT is driven by the drive wheel (front wheel) W.
It is connected to _FL and W _FR . Therefore, the front left and right wheels W _FL , W _FR can be driven by the engine EG as well as the motor generator MG that is powered. Conversely, if the motor generator MG is regeneratively operated, the front left and right wheels W _FL , W _FR are regeneratively operated. Torque, that is, electric braking force acts, and at the same time, electric power regenerated by the motor generator MG is charged in a battery (not shown). Also, the clutch C
In addition to its role as a so-called running clutch, L stops the engine EG and disconnects the clutch CL to disconnect the engine EG from the drive system, for example, when the torque of the engine EG is not required. Also used for.

The drive wheels W _FL , W _FR and the non-drive wheels W _RL ,
Wheel cylinders 1FL to 1RR as braking cylinders are attached to W _RR , and the supply pressure to these wheel cylinders 1FL to 1RR is adjusted by a brake actuator unit 10 controlled by a brake control unit 9 described later. It is like this.

The engine EG is provided with an electronically controlled throttle valve in an intake pipe line (not shown) whose opening is adjusted by a rotation angle according to the number of steps using a step motor as an actuator. Is controlled by the engine control unit 37. The engine control unit 37 is configured to include a microcomputer and the like, and has a motor generator control unit 3 described later.
The engine EG is driven in response to a command signal from 8 for instructing the start and stop of the engine EG.

The motor generator control unit 38 includes a microcomputer and the like,
An accelerator operation amount signal from an accelerator operation amount sensor (not shown) provided on the accelerator pedal, an engine speed from a rotation speed sensor (not shown) provided on the engine EG,
Based on the actual speed ratio of the continuously variable transmission CVT, the vehicle speed, etc., the motor negator MG, the clutch CL, and the engine EG
Is controlled.

That is, for example, when it is determined from the accelerator pedal operation amount signal that the accelerator pedal is in the depressed state by referring to a preset traveling pattern control map or the like, the current traveling state of the vehicle is the motor generator MG.
It is determined whether it is a motor travel area in which only the engine EG is traveled, an engine travel area in which only the engine EG is traveled, or a hybrid travel area in which only the engine EG is used for normal travel and the motor generator MG is used during acceleration. The engine EG, the motor generator MG, and the clutch CL are controlled according to the determined traveling area.

When it is determined that the accelerator pedal is open, if the vehicle speed is zero, it is determined that the vehicle is stopped and the clutch CL is opened. If the vehicle speed is not zero and the antilock brake control process executed by the brake control unit 9 is not operating, the amount of power generation is detected by referring to an energy recovery amount calculation map (not shown), for example. The motor generator MG is operated as a generator in accordance with the amount of power generation to control the so-called regenerative operation state, and the electric energy is collected in a power storage device (not shown). Further, the calculated power generation amount is notified to the brake control unit 9 as power generation amount information. Meanwhile, the brake control unit 9
When the anti-lock brake control process in 1 is operating, the regenerative operation of the motor generator MG is stopped, but is stopped at a predetermined deceleration, for example, according to the running state of the vehicle.

The continuously variable transmission CVT is controlled by a continuously variable transmission control unit 39. The continuously variable transmission control unit 39 is configured to include a microcomputer and the like, and has a target gear ratio set based on, for example, vehicle speed, engine speed, and accelerator pedal operation amount, and input speed of the continuously variable transmission CVT. The speed change control of the continuously variable transmission CVT is performed so that the speed change ratio calculated based on the output speed matches, and the target speed change ratio is set based on, for example, a preset speed change pattern control map. The gear ratio is controlled so that the gear ratio becomes larger as it decreases, the gear ratio becomes larger as the accelerator pedal operation amount increases, and the gear ratio becomes larger as the engine speed increases. There is.

FIG. 2 shows an example of the brake actuator unit 10. The brake actuator unit 10 is a four-wheel integrated control in which the working fluid pressure for all four wheels is cut off from the master cylinder to perform pressure increase / decrease control. Actuator unit 5, an anti-lock brake control actuator unit 6 for avoiding the locking tendency of each wheel and ensuring both a braking distance and a steering effect, and only the working fluid pressure to the front wheels is mainly reduced. A front wheel control actuator unit 7 for controlling is provided.

The master cylinder 2 shown in the figure is capable of outputting the same working fluid pressure corresponding to the depression amount of the brake pedal 3 to the two systems. Basically, the wheel cylinder of the front left wheel (hereinafter simply referred to as the front left wheel). 1FL and wheel cylinder for rear right wheel (rear right wheel cylinder) 1
The RR is connected to one system of the master cylinder 2 and has a front right wheel wheel cylinder (front right wheel cylinder) 1F.
R and a rear left wheel cylinder (rear left wheel cylinder) 1RL are connected to the other system of the master cylinder 2 to form a so-called X piping type. As is well known, the advantage of this X piping system is that even if an abnormality occurs in either one of the piping systems, the other piping system remains on the front wheel side and the rear wheel side, and on the vehicle left side and the right side. The point is that the braking force is balanced and the vehicle stability is secured. A booster 4 is interposed between the brake pedal 3 and the master cylinder 2, and details of the structure and the like will be described later.

Here, in order to facilitate understanding, the structure of each wheel cylinder 1FL to 1RR will be described from the structure of the antilock brake control actuator unit 6. The structure of the pressure control valve in the actuator unit 6 for controlling the anti-lock brake is similar to that of the existing conventional recirculation type. For example, one system from the master cylinder 2 is branched into two and the other system is branched. Is also branched into two, and the respective wheel cylinders 1FL to 1RR are connected to the respective branch destinations via pressure-increasing control valves 51FL to 51RR for antilock brake control. These pressure increase control valves 51FL to 51RR are two-position switching solenoid valves that are normally open for compensating for abnormal conditions, so-called fail safe. It should be noted that each of the pressure increasing control valves 51FL to 51RR includes a wheel cylinder 1FL to a wheel cylinder 1FL.
The check valves 52FL to 52RR that allow only the return of the working fluid from the 1RR to the master cylinder 2 side are bypass-connected.

Further, the pressure reducing control valves 53FL to 53RR for controlling antilock brakes, which are normally closed two-position switching solenoid valves, are connected to the downstream side of the pressure increasing control valves 51FL to 51RR for controlling antilock brakes. Reservoirs 54P, 5 common to the output side for each system
4S and the pumps 55P and 55S are branched and connected to each other, and the damper 5
The discharge side of each pump 55P, 55S is connected to each system of the master cylinder 2 via 6P, 56S. Accordingly, the working fluid pressure of each wheel cylinder 1FL to 1RR is reduced by the pressure reducing control valves 53FL to 53RR and the pump 55.
It is returned to each system of the master cylinder 2 via P, 55S and dampers 56P, 56S.

The antilock brake control actuator unit 6 is controlled by an ABS controller 9a constituting a brake control unit 9 based on a wheel speed signal from a wheel speed sensor. That is, the target wheel cylinder pressure is calculated based on the detection signal of a wheel speed sensor (not shown), the wheel acceleration calculated based on the detection signal, the target wheel speed, etc., and this target wheel cylinder pressure matches the estimated current master cylinder pressure. When these values match, the pressure increase control valves 51FL to 51RR are closed to maintain the working fluid pressure of the wheel cylinders 1FL to 1RR of the wheel, and the estimated master cylinder pressure is higher than the target wheel cylinder pressure. Is higher, the pressure reducing control valves 53FL to 53RR are opened while operating the pumps 55P and 55S, and the working fluid pressure of the wheel cylinders 1FL to 1RR is returned to the master cylinder 2 side to reduce the pressure, and vice versa. If the estimated master cylinder pressure is lower than the wheel cylinder pressure, the pressure reduction control bar Further closing the blanking 53FL～53RR, pressure increase the working fluid pressure of the wheel cylinder 1FL~1RR open pressure increase control valve 51FL～51RR. By repeating this series of operations, it is possible to reliably reduce the speed of each wheel in the vicinity of the target wheel speed at which the braking distance can be ensured and the steering effect is high. Make sure to decelerate the speed.

Further, in this embodiment, the pressure increasing control valves 51FL, 51 for controlling the front left and right wheels antilock brakes are used.
Downstream of FR and front left and right wheel cylinders 1FL, 1F
A front wheel control actuator unit 7 is interposed between the R and R. This front wheel control actuator unit 7
Is a normally open two-position switching solenoid valve interposed between the front left and right wheel anti-lock brake control pressure increasing control valves 51FL and 51FR and the front left and right wheel cylinders 1FL and 1FR. Wheel decompression control switching valves 41FL and 41FR, and check valves 42FL and 42FR bypass-connected to the front left and right wheel cylinders 1FL and 1FR to allow only recirculation to the master cylinder 2 side, and further bypass-connected to the check valves 42FL and 42FR. A proportioning valve 43 capable of substantially reducing the working fluid pressure to the front left and right wheel cylinders 1FL, 1FR.
It consists of FL and 43FR. Incidentally, the output pressure of the proportioning valves 43FL and 43FR is gradually increased with a pressure increase gradient smaller than the pressure increase gradient of the input pressure when the pressure is relatively low with respect to the input pressure on the master cylinder 2 side, for example. When the pressure is increased and the input pressure becomes equal to or higher than a predetermined value, a pressure increasing gradient that is the same as the pressure increasing gradient of the input pressure is applied.

This front wheel control actuator unit 7
Is controlled mainly by the regenerative braking controller 9b that constitutes the brake control unit 9.
That is, when the motor generator MG is regeneratively operated, the front left and right wheel pressure reducing control switching valve 41FL,
Close the 41FR to move the proportioning valve 4
Front left and right wheel cylinder 1F by 3FL, 43FR
The working fluid pressure of L, 1FR is controlled to be lower than the supply pressure on the master cylinder 2 side. That is, the vehicle of this embodiment is FF
It is a type, and both the engine and the motor generator are connected only to the front wheels. Therefore, since the regenerative torque generated by the motor generator is also applied only to the front wheels, the front left and right wheel cylinders 1 are divided by the braking force generated by the regenerative torque.
It is necessary to reduce the working fluid pressure of FL, 1FR. Conversely, if the regenerative torque from the motor generator is applied only to the front wheels, the working fluid pressure of all four wheel cylinders would have been reduced. The problem becomes larger, for example, the antilock brake control is started early. Therefore, in the present embodiment, the proportioning valves 43FL and 43FR corresponding to the braking force due to the regenerative torque are used.
Thus, the working fluid pressure of the front left and right wheel cylinders 1FL and 1FR is reduced. However, the regenerative torque generated by the motor generator changes depending on, for example, the vehicle speed.
In this embodiment, for example, the proportioning valve can reduce the pressure by a small amount of regenerative torque, which is relatively stable and can be generated at medium and high speeds.

Next, the booster 4 and the working fluid pressure source for the booster 4 will be described before the four-wheel integrated control actuator unit 5. In the hybrid vehicle as in the present embodiment, the engine may be stopped, so the electric pump 11 is used as the working fluid pressure source for the booster 4. The electric pump 11 draws in the working fluid in the main reservoir 8 and the check valve 1
2 and discharge. An accumulator 13 is connected to the discharge side of the electric pump 11 and further connected to the input side of the booster 4. By arranging pressure switches 14 and 15 on the upstream side and the downstream side of the accumulator 13 so that the electric pump 11 operates regardless of which of the pressure switches is lowered, the working fluid pressure in the accumulator 13 That is, the fluid pressure supplied to the booster 4 can be maintained above a predetermined value.

The basic structure of the booster 4 is the same as the existing one. That is, in the state where the brake pedal 3 is not depressed as shown in FIG. 3 (the state where the brake pedal 3 is depressed), the input shaft 71 is retracted to the right in the figure, and as a result, the steel ball 72 is Since it is pressed against the valve seat 73 by the spring 74, the working fluid pressure from the accumulator 13 taken in from the outer periphery of the piston 75 is applied to the piston 7 concerned.
5 cannot flow into the cylinder chamber 76 inside, and the force for pressing the piston 75 is not generated. The cylinder chamber 76 also communicates with the inside of the booster body 70.
A rod 77 connected to the master cylinder 2 is extended to the piston 75. In addition, reference numerals 78,
Reference numeral 79 is a return spring for retracting the piston 75 and the rod 77 to the right in the figure in a state where the brake pedal 3 is not depressed.

When the brake pedal 3 is depressed from this state, the input shaft 71 is moved leftward in the figure against the elastic force of the spring 80 interposed between the input shaft 71 and the valve seat 73, and the tip end portion thereof is moved. Moves the steel ball 72 together with the holder 82 to the left in the drawing against the elastic force of the spring 74, so that the steel ball 72 is separated from the valve seat 73. Then, the working fluid pressure from the accumulator 13 flows into the cylinder chamber 76 in the piston 75 from the gap between the input shaft 71 and the valve seat 73 through the port 81 formed in the input shaft 71. Since the piston 75 is pressed leftward in the figure together with the valve seat 73, the rod 77 is moved to the master cylinder 2 side, and the working fluid pressure in the master cylinder 2 is increased. Of course, after this, the piston 75 together with the valve seat 73 is also replaced by the input shaft 71.
May be pushed to the left, but since the piston is always pushed first by the working fluid pressure, a large propulsive force can be obtained even if the pedaling force of the brake pedal 3 is small. The working fluid pressure in 2 is boosted.

Next, when the brake pedal 3 is stopped with the brake pedal 3 depressed to some extent, the valve seat 73 is pressed by the elastic force of the spring 80.
And the input shaft 71 are separated from each other, and as a state, the input shaft 71 is retracted relatively to the right in the drawing with respect to the valve seat 73 (however, the input shaft 7
1 is in contact with the steel ball 72), and the steel ball 72 is pressed against the valve seat 73 again by the elastic force of the spring 74, so that the gap between the two is closed and the working fluid pressure in the cylinder chamber 76 is closed. Is enclosed, and an auxiliary force for maintaining the piston 75 and the rod 77 in the state of moving to the master cylinder 2 side is obtained by the enclosed pressure.

On the other hand, from this state, the brake pedal 3
Input shaft 7 becomes free when you release your foot from it
1 is further retracted rightward in the figure by the spring 80, and the steel ball 72 and the input shaft 71 are separated from each other while the steel ball 72 remains in contact with the valve seat 73. Then, the working fluid pressure in the cylinder chamber 75 flows through the gap between the input shaft 71 and the valve seat 73 in the flow path 83 and the input shaft guide 84 formed from the tip of the input shaft 71. It flows back to the main reservoir 8 through the passages 85 and 86 and the passage 87 formed in the booster body 70.

As described above, in the booster 4 of the present embodiment, the working fluid pressure from the accumulator 13 always flows into the cylinder chamber 76 to increase the pressure from the start of depression of the brake pedal 3. Therefore, in the present embodiment, a flow for increasing the working fluid pressure in the cylinder chamber 76 with the depression of the brake pedal 3 and taking it out as a working fluid pressure from a fluid pressure source different from the working fluid pressure of the master cylinder 2. A passage 88 was formed in the valve body 70. The working fluid pressure taken out from here is taken into the actuator unit 5 for four-wheel integrated control, which will be described later, and is used for braking force control during regeneration.

Next, the overall configuration of the four-wheel integrated control actuator unit 5 will be described. First, for each system of two working fluid pressures from the master cylinder 2,
Regenerative switching valves 21P and 21S, which are two-position switching pilot valves that use the working fluid pressure extracted from the booster 4 as a pilot pressure, are interposed. The regenerative switching valve 21P, 2 consisting of this two-position switching pilot valve
The P port of 1S is connected to the output side of each system of the master cylinder 2, and its A port is branched to the antilock brake control pressure increasing control valves 51FL to 51RR, and its B port is a stroke composed of a kind of accumulator. It is connected to the simulators 22P and 22S. The regenerative switching valves 21P and 21S communicate with the P port and the A port in a normal state where there is no pilot pressure, and also check valves 20P and 20S.
Allows only reflux from B port to P port and A port. Further, in the switching state by the pilot pressure, the A port is shut off and the P port and the B port are connected. By the way, the stroke simulator 22P, 2
The 2S return spring has a spring constant equivalent to the working fluid pressure reaction force generated in the booster 4 and the master cylinder 2, and the excess working fluid is returned to the main reservoir 8. In addition, each regeneration switching valve 21
Pressure sensors 2 are provided on the upstream and downstream sides of P and 21S, respectively.
3P, 23S and pressure sensors 24P, 24S are provided.

On the other hand, the working fluid pressure extraction system of the booster 4 is provided with the regeneration switching valve 21 via a fail-safe valve 25 which is a normally closed electromagnetic two-position switching valve.
It is branched and supplied as the pilot pressure of P, 21S. In addition, this fail-safe valve 25 has a booster 4
A check valve 26 that permits only the return to the side and a bypass valve 27 that is a normally closed two-position switching pilot valve are connected in parallel by bypass, and the pilot pressure of the bypass valve 27 is the downstream pressure of the fail-safe valve 25. (Or the downstream pressure of the bypass valve 27 itself). Accordingly, when the fail-safe valve 25 is opened in principle, its downstream pressure, that is, the bypass valve 27.
Since the pilot pressure of the
When the fail-safe valve 25 is closed when the working fluid pressure from the booster 4 is low, the downstream pressure, that is, the pilot pressure of the bypass valve 27 is reduced, so that the bypass valve 27 is also closed. .

Further, the orifice 2 is provided between the fail-safe valve 25 and each regenerative switching valve 21P, 21S.
8, the regeneration switching valve 2 is provided in the orifice 28.
The check valve 29 which permits only the inflow to 1P and 21S (the pilot pressure thereof) is bypass-connected. Although one orifice 28 and one check valve 29 are provided on the upstream side of the branch in the drawing as a representative, one orifice is provided on the downstream side of the branch, that is, each regenerative switching valve 21.
You may make it interpose every P and 21S.

Further, on the downstream side of the fail-safe valve 25 or on the downstream side of the bypass valve 27, a pressure increasing control valve 30 for four-wheel integrated control, which is a normally open two-position switching solenoid valve, and a normally closed two-position valve. A four-wheel integrated control depressurization control valve 31, which is a switching solenoid valve, and a four-wheel integrated control reservoir 32 are connected in series, and the return amount of the reservoir 32 is returned to the main reservoir 8. The pressure increasing control valve 30 for the four-wheel integrated control is provided.
And the four-wheel integrated control depressurization control valve 31 are connected to the input port of the pressure control cylinder 16. The four-wheel integrated control pressure-increasing control valve 30 includes a check valve 33 that allows only the recirculation from the pressure control cylinder 16.
And a relief valve 34 that relieves the upstream side working fluid pressure of the pressure increase control valve 30 at a predetermined pressure or more are connected in parallel by bypass. Further, a check valve 35 that allows only the return from the four-wheel overall control reservoir 32 is bypass-connected to the four-wheel overall control depressurization control valve 31. Further, a pressure sensor 36 for detecting the input working fluid pressure of the pressure control cylinder 16 may be attached if necessary.

The cylinder 16 for pressure control has the same shape, that is, the cylinder portions 18P and 18S in which the pistons 17P and 17S having at least the pressure receiving area on the input side and the pressure receiving area on the output side are housed are opposed to each other in one cylinder body. And each cylinder portion 18P, 18S
The output ports of are connected to the respective systems from the master cylinder 2 on the downstream side of the regeneration switching valves 21P and 21S. Of course, each cylinder part 18P, 18S
The return springs 19P and 19S are also of the same specifications including the spring constant. That is,
Two cylinder parts 18 are provided for the input working fluid pressure.
The same working fluid pressure can be output from P and 18S to each of the two systems from the master cylinder 2. Further, the so-called pressure receiving area ratio between the pressure receiving area on the input side and the pressure receiving area on the output side of each of the pistons 17P and 17S is the master cylinder 2
The ratio of the output pressure to the working fluid pressure taken out of the booster 4 is substantially equal to the ratio.

The four-wheel integrated control actuator unit 5 is mainly composed of the brake control unit 9
Is controlled by the above-described regenerative braking controller 9b. That is, when no abnormality is detected as the braking force control device, the fail safe valve 2
When 5 is opened and the brake pedal 3 is depressed with the antilock brake control not being performed, the working fluid pressure taken out from the booster 4 is increased.
The bypass valve 27 whose pilot pressure is the downstream pressure of the fail-safe valve 25 is also switched and opened. Further, the downstream pressure of the fail-safe valve 25 passes through a check valve 29 and the regeneration switching valves 21P, 21P.
Since the pilot pressure is also supplied to S, the regenerative switching valves 21P and 21S are switched, and the downstream side, that is, the wheel cylinders 1FL to 1RR side is shut off, and each system of the master cylinder 2 has the stroke simulator 22P. , 22S. Therefore, the working fluid pressure of each system of the master cylinder 2 operates the pistons in the stroke simulators 22P and 22S, but its return spring generates a reaction force equivalent to the reaction force in the master cylinder 2 and the booster 4, The driver does not feel uncomfortable when depressing the brake pedal 3.

On the other hand, since the regenerative torque by the motor generator can be obtained from the vehicle speed, the gear ratio, etc., as described above, the braking force of the front left and right wheels is calculated and the pressure sensor 23P on the master cylinder side is calculated. , 23S
The braking force when the working fluid pressure is supplied to each of the wheel cylinders 1FL to 1RR is calculated from the working fluid pressure detected in 1., and the braking force composed of the difference value between the two and the wheel cylinder side pressure sensors 24P, 24S. The output pressure from the pressure control cylinder 16 is controlled so that the braking force corresponding to the detected working fluid pressure matches. Here, since the pressure control cylinder 16 can supply the same working fluid pressure to the two X piped systems, in order to control the pressure increase / decrease in the same manner, the pressure control cylinder 16 must be controlled. It suffices to control the input pressure to the pressure increase / decrease. At this time,
The ratio between the output pressure and the input pressure of the pressure control cylinder 16 is determined by the pistons 17P, 1 of the two cylinder portions 18P, 18S.
Since it is the inverse ratio of the pressure receiving area ratio of 7S, the required working fluid pressure, that is, the amount of increase or decrease in the input pressure with respect to the amount of increase or decrease in the output pressure is set. Then, the four-wheel integrated control pressure-increasing control valve 30 and the four-wheel integrated control pressure-decreasing valve 31 may be controlled to open and close according to the amount of increase or decrease of the input pressure. In addition,
Regarding the pressure increasing / decreasing control of the input pressure to the pressure control cylinder 16, for example, PWM based on the existing duty ratio is used.
(Pulse Width Modulation) control etc. can be applied,
Detailed description thereof will be omitted. In principle, the working fluid pressure reduced by the four-wheel integrated control decompression valve 31 is stored in the four-wheel integrated control reservoir 32.

Further, for example, when the regeneration switching valve is of a solenoid drive type, an electrical structure for driving the solenoid is required, and the regenerative operation time due to the depression of the brake pedal 3 as described above becomes long. ,
For example, there is a problem that the excitation time of the solenoid becomes long and the amount of heat generation becomes large, and the energy loss becomes large. However, in the present embodiment, in order to drive the regeneration switching valves 21P and 21S, the brake pedal Three
Since the working fluid pressure in the booster 4 that constantly occurs during stepping on is used as the pilot pressure, the structure is simplified and an excessive amount of heat generation and energy loss can be suppressed and prevented.

Even when the brake pedal 3 is depressed during the regenerative operation and the working fluid pressure taken out from the booster 4 is reduced by slightly returning the brake pedal 3, the regeneration switching valve 21P. , 2
Since the pilot pressure to 1S is reduced only slowly through the orifice 28, the regenerative switching valve 21
It is possible to prevent the P and 21S from accidentally returning to the normal position and to continue the regenerative cooperative control. On the other hand, when the brake pedal 3 is stepped on, the working fluid pressure taken out from the booster 4 flows from the check valve 29 side as the pilot pressure of the regeneration switching valves 21P, 21 without passing through the orifice 28, so that the necessary responsiveness is secured. can do.

Further, when the foot is released from the brake pedal 3 from this state, the working fluid pressure taken out from the booster 4 is also reduced as described above, so that the regeneration switching valve 2
The pilot pressure of 1P, 21S is also slowly reduced through the orifice 28, and the regeneration switching valves 21P, 2S
1S returns to the normal position, and the master cylinder 2 is again connected to the wheel cylinders 1FL to 1RR side. Also,
The working fluid in the four-wheel integrated control reservoir 32 passes through the check valve 35, and together with the working fluid in the pressure control cylinder 16, the check valve 33 and the check valve 2.
Return to booster 4 through 6.

If an abnormality is detected without the brake pedal 3 being depressed, the fail safe valve 2 is detected.
When the valve 5 is closed, the bypass valve 27 is also kept closed even when the brake pedal 3 is next stepped on, so that the working fluid pressure in the booster 4 is not supplied to the downstream side thereof and the regenerative switching valve 21P. , 21S is the master cylinder 2
And the wheel cylinders 1FL to 1RR are maintained in a communicating state, and a fail-safe function is obtained.

On the other hand, when an abnormality is detected while the brake pedal 3 is being depressed, the fail-safe valve 25 is immediately closed as in the above case. However, at this time, even if the fail-safe valve 25 is closed, the downstream pressure of the fail-safe valve 25, that is, the working fluid pressure on the booster 4 side of the check valve 26 is high, so the pilot pressure of the regeneration switching valves 21P and 21S is sealed. Therefore, the regenerative switching valve 21P,
21S remains blocked from the working fluid system from the master cylinder 2. However, at this time, the pilot pressure of the enclosed regenerative switching valves 21P and 21S, that is, the downstream pressure of the fail-safe valve 25 acts as the pilot pressure of the bypass valve 27, so that the bypass valve 27 is maintained in the open state. Therefore, as a similar fail-safe measure, the pressure increasing control valve 30 for controlling four wheels is integrated.
Is maintained in the open state and the four-wheel integrated decompression control valve 31 is maintained in the closed state. Therefore, the working fluid pressure taken out from the booster 4 continues to be supplied to the two systems through the pressure control cylinder 16, so at least the brake is applied. The braking by the working fluid pressure can be maintained until the foot is released from the pedal 3. Since the pressure receiving area ratio of the pistons 17P, 17S of the two cylinder parts 18P, 18S of the pressure control cylinder 16 is set to the ratio of the output pressure of the master cylinder 2 and the working fluid pressure taken out from the booster 4, The working fluid pressure from the pressure control cylinder 16 obtained from time to time becomes the same as that from the master cylinder 2, stabilizing the braking force and causing no discomfort.

Besides this, the piston 1 of the two cylinder portions 18P and 18S of the pressure control cylinder 16 is also provided.
By setting the pressure receiving area ratio of 7P, 17S to the ratio of the output pressure of the master cylinder 2 and the working fluid pressure taken out from the booster 4, the working fluid pressure from the pressure control cylinder 16 becomes equal to that from the master cylinder 2. Therefore, the control mode on the downstream side of the antilock brake control actuator unit can be shared with that for the working fluid pressure from the master cylinder 2 to facilitate control.

The brake control unit 9 is
An ABS controller 9a for controlling the antilock brake control actuator unit 6 in accordance with the difference between the target wheel cylinder pressure and the estimated wheel cylinder pressure,
The four wheel integrated control actuator unit 5 and the front wheel control actuator unit 7 are controlled in accordance with the operating status of the ABS controller 9a and the operating status of the motor generator controller 38 to control the working fluid pressure to the wheel cylinders 1FL to 1RR. The regenerative braking controller 9b performs so-called regenerative cooperative control for adjustment. The ABS controller 9a and the regenerative braking controller 9b are each configured to include a microcomputer and the like, and the engine control unit 37, the motor generator controller 38, and the continuously variable transmission control unit 39 are controlled while performing mutual communication. Is supposed to do.

The ABS controller 9a controls the working fluid pressure to the wheel cylinders 1FL to 1RR as described above and also controls the wheel cylinders 1FL to 1RR.
When the working fluid pressure to the vehicle is controlled to a reduced pressure state, the ABS operation flag ASj (j = FL to RR) of the corresponding wheel is set to "1" and output to the motor generator control unit 38 and the regenerative braking controller 9b. . The ABS operation flag ASj is a table to flag that the pressure reduction control of the hydraulic fluid pressure to the wheel cylinders 1FL~1RR by anti-lock brake control process becomes started with anti-lock operation state. Whether the pressure reduction control is being performed by the four-wheel integrated control actuator unit 5 and the front-wheel control actuator unit 7,
Pressure reduction information such as a pressure reduction amount by pressure reduction control is input from a regenerative braking controller 9b described later. When the ABS operation flag is ASj = 1, when the pressure reduction control of the working fluid pressure by the actuator units 5 and 7 is being performed, the pressure reduction amount of the working fluid pressure by the actuators 5 and 7 during the pressure reduction control is performed. Based on the above, the pressure reducing time T when the working fluid pressure is first reduced after the ABS control processing is started.
Correct p.

The regenerative braking controller 9b, based on the power generation amount information notified from the motor generator control unit 38, has a working fluid equivalent to a braking force generated when the motor generator MG is driven to obtain this power generation amount. The four-wheel integrated control actuator unit 5 and the front-wheel control actuator unit 7 are appropriately controlled so as to calculate the pressure and reduce the working fluid pressure.
That is, the electric braking force applied to the vehicle due to the operation of the motor generator MG as a generator is offset by reducing the operating fluid pressure to the wheel cylinders 1FL to 1RR by the braking force decrease accompanying the pressure reduction. As a result, the regenerative cooperative control of the working fluid pressure is performed so that the braking force according to the depression amount of the brake pedal 3 acts on the vehicle. This is, for example, according to a preset control map, the four-wheel integrated control actuator unit 5
One or both of the front wheel control actuator unit 7 and the front wheel control actuator unit 7 are driven to reduce the working fluid pressure corresponding to the braking force associated with the regenerative operation of the motor generator MG.

The regenerative braking controller 9b receives the ABS operation flag ASj from the ABS controller 9a and controls the pressure reduction of the working fluid pressure by either the four-wheel integrated control actuator unit 5 or the front wheel control actuator unit 7. The ABS controller 9a is notified of the operation status such as whether or not the operation is performed and the pressure reduction information indicating the pressure reduction amount.

Further, the regenerative braking controller 9b is
When any one of the BS operation flags is ASj = 1 and it is detected that the control of the working fluid pressure by the antilock brake control processing is started, the four wheel integrated control actuator unit 5 and the front wheel control actuator unit 7 are operated. Stop regenerative coordinated decompression. Specifically, for the four-wheel integrated control actuator unit 5, the fail-safe valve 25 is controlled to the open state, and the bypass valve 27 is opened accordingly, and the four-wheel integrated control pressure increase control valve is also opened. The valve 30 is controlled to be in an open state, and the four-wheel integrated control depressurization control valve 31 is controlled to be closed. This allows
Since the supply pressure to the pressure control cylinder 16 is increased and its output pressure is increased to output a working fluid pressure almost equal to the master cylinder pressure, the regenerative coordinated pressure reduction by the four-wheel integrated control actuator unit 5 is performed. Be stopped. On the other hand, regarding the front wheel control actuator unit 7, the front left and right wheel depressurization control switching valves 41FL and 41FR are controlled to the open state, and the working fluid pressure on the upstream side thereof is passed through the proportioning valves 43FL and 43FR. Supply to 1FL and 1FR.

FIG. 4 is a flow chart showing an example of the processing procedure of the ABS control processing in the ABS controller 9a, and this processing is executed, for example, in a preset predetermined cycle. This control process is well known and is equivalent to, for example, the antilock brake control process described in Japanese Patent Application Laid-Open No. 8-150917, and therefore will be briefly described here.

That is, first, in step S1, the master cylinder pressure, the wheel speed Vw of each wheel and the wheel thereof are determined based on the detection values of the wheel speed sensor (not shown) and the detection values of the pressure sensors 23P and 23S on the master cylinder side. The acceleration is calculated, and then the process proceeds to step S2 to calculate the vehicle body speed gradient and the estimated vehicle body speed based on each wheel speed Vw.

Next, the process proceeds to step S3, the control signal and the previous master cylinder pressure or the like to the antilock brake control for A click Ju eta unit 6 at the time of the previous process execution and the detected master cylinder pressure in the processing of step S1 Based on the above, the current wheel cylinder pressures P _{FL to} P _RR of the wheel cylinders 1FL to 1RR are estimated. Next, step S
4, the target wheel speed Vw ^* is calculated, for example, as 80% of the estimated vehicle speed. Then, the process proceeds to step S5, the calculated target wheel speed Vw ^* is compared with the wheel speed Vw calculated in step S1, and when Vw ^* > Vw, the process proceeds to step S6 to set the target wheel deceleration Vw ^* ′. set to "0", when a Vw ^* ≦ Vw proceeds to step S7, sets the target wheel deceleration Vw ^* 'and to e.g. preset value -Vw _0'.

Next, in step S8, the target wheel cylinder pressure P ^* for each wheel cylinder 1FL to 1RR is set according to a preset control map, for example ^.
Calculate _FL- P ^* _RR . Then, anti which the process proceeds to step S9, and executes the actuator control process, the target wheel cylinder pressure P ^* _FL ~P ^* _RR, depending on the difference between the estimated wheel cylinder pressure P _FL to P _RR calculated in step S3 determining the control signal to the lock brake control a click Ju eta unit 6, and outputs this.

[0058] A click Chueta control process in step S 9, as shown in FIG. 5, first, at step S11, the target wheel cylinder pressure P calculated in step S8
^{* It} is determined whether or not _I (I = FL to RR) matches the master cylinder pressure detected in the process of step S1, and when both match, the process proceeds to step S12,
ABS operation flag A indicating that anti-lock brake control is in progress
S is reset to "0", then the process proceeds to step S13, the pressure increasing / decreasing time Tp representing the holding time of the output control signal is set to "1", and then the process proceeds to step S14 to set the target cylinder pressure. After the slow pressure increase period m, which indicates the period for monitoring the error between P ^* _I and the actual cylinder pressure P _I , is set to "1", the process proceeds to step S15.

In this step S15, the pressure increasing / decreasing time Tp
Is positive, "0", or negative, and if Tp> 0, the process proceeds to step S16, and the value obtained by subtracting "1" from the pressure increase / decrease time Tp is newly added. The pressure increase / decrease time is Tp. Next, in step S17, the pressure increase control valve 51 _I is opened and the pressure reduction control valve 5 is opened.
3 _I is closed to control the pressure.

Further, the determination result of step S15 is Tp =
When it is 0, the routine proceeds to step S18, where both the pressure increasing control valve 51 _I and the pressure reducing control valve 53 _I are controlled to the closed state and held. Further, when the determination result of step S15 is Tp <0, the process proceeds to step S19, the ABS operation flag AS is set to "1", then the process proceeds to step S20, and the pressure increase / decrease time Tp is set to "1". The value obtained by adding is set as a new pressure increasing / decreasing time Tp. Then, the process proceeds to step S21, and the pressure increase control valve 51
_The pressure is reduced by controlling _I to a closed state and the decompression control valve 53 _I to an open state.

If the target cylinder P ^* _I and the master cylinder pressure P _I do not match as a result of the determination in step S11, the process proceeds to step S22, and the gradual pressure increase period m
The value obtained by subtracting “1” from is set as a new slow pressure increasing cycle m, and the process proceeds to step S23. In this step S23,
It is determined whether or not the variable m is positive. If m> 0, the process proceeds to step S15, and if m ≦ 0, the process proceeds to step S24.

In this step S24, the error P _ERR (= P ^* _I- P _I ) between the target wheel cylinder pressure P ^* _I and the estimated wheel cylinder pressure P _I is calculated, and then the step S2
Go to 5. In this step S25, it is determined whether the error P _ERR is positive or negative including zero, and when P _ERR ≧ 0, the process proceeds to step S26, and the error P _ERR is divided by the reference value P _0. Step S2 after calculating the pressure increase / decrease time Tp according to the following equation (1)
Move to 7.

Tp = INT (P _ERR / P ₀ ) ... (1) When the determination result of step S25 is P _ERR <0, the process proceeds to step S27 and the error P _ERR is multiplied by a constant K _G. Calculated value is divided by the sum of the estimated wheel cylinder pressure P _I and the reference value P _0, and the value is increased and decreased according to the following equation (2).
Go to 8.

Tp = INT [K _G · P _ERR / (P _I + P ₀ ) ... (2) In step S 28, whether the pressure increase / decrease time Tp is positive, “0”, or negative. And Tp =
When it is 0, the process proceeds to step S29 to set the slow pressure increasing period m to "1", and then the process proceeds to step S15, where T
When p> 0, the process proceeds to step S30 to set the slowly increasing pressure cycle m to a predetermined value m ₀ , and then proceeds to step S31 to set the control flag Fz representing the slowly increasing pressure state to "1". Then, the process proceeds to step S15.

When Tp <0 in step S28, the process proceeds to step S32, and whether or not the ABS operation flag AS (n-1) at the time of executing the previous processing which is held in advance is "0". If AS (n-1) = 0 is not satisfied, the process directly proceeds to step S33 to set the depressurization cycle m to a predetermined value m ₀ , and then proceeds to step S34, and the control flag indicating the gradually increased pressure state. After resetting Fz to "0", the process proceeds to step S15.

On the other hand, in step S32, AS (n-
When 1) = 0, the process proceeds to step S35,
Based on the pressure reduction information from the regenerative braking controller 9b, it is determined whether or not the regenerative coordinated pressure reduction is performed on the corresponding wheel for which the anti-lock brake control is being performed, and when the regenerative coordinated pressure reduction is not performed. To step S3
Move to 3. Then, when the regenerative coordinated pressure reduction is being performed on the corresponding wheel of the antilock brake control in step S35, the process proceeds to step S36, and the antilock brake is performed based on the pressure reduction information from the regenerative braking controller 9b. For example, by multiplying the depressurization amount of the regenerative coordinated depressurization performed on the corresponding control wheel by a preset constant K or the like, the depressurization correction time Tα (= K
_VL ) is calculated, and this decompression correction time Tα is added to the decompression time Tp, and this is set as a new decompression time Tp.

Then, the process proceeds to step S37, in which the predetermined value m ₀ and the cycle correction amount mα according to the pressure reduction correction time Tα are set.
After adding and and setting this as the decompression cycle m, step S3
Go to 4. This cycle correction amount mα is calculated in step S36.
The period is a period sufficient to reduce the pressure during the pressure reduction time Tp set in.

Next, the operation of the above embodiment will be described with reference to the timing chart of FIG. Now, assuming that the vehicle is in a traveling state, the motor generator controller 38 refers to a traveling pattern control map (not shown) based on the accelerator pedal operation amount and the vehicle speed, and the traveling state is a motor traveling in which only the motor generator 4 is traveling. It is determined whether it is a region, an engine traveling region in which only the engine 1 is traveling, or a hybrid traveling region in which the normal traveling is performed only by the engine 1 and the motor generator 4 is used at the time of acceleration. Control the engine 1, the motor generator 4, and the clutch 2. As a result, either one or both of the motor generator 4 and the engine 1 are driven according to the traveling state of the vehicle, and the vehicle travels by the traveling drive force from these.

From this state, when the driver releases the accelerator pedal and depresses the brake pedal 3 at time t ₁ to enter the braking state, the motor gelator controller 38 calculates an energy recovery amount calculation map and the like to generate power. Is calculated and the motor generator 4 is operated as a generator according to the amount of power generation to control the so-called regenerative operation state, and this electric energy is collected in a power storage device or the like.

In response to this, the regenerative braking controller 9b produces a working fluid pressure corresponding to the braking force applied to the vehicle by the motor generator MG controlled to the regenerative operating state, based on the power generation amount information from the motor generator controller 38. Calculate and calculate the working fluid pressure for wheel cylinder 1
Four-wheel integrated control actuator unit 5 and front-wheel control actuator unit 7 based on, for example, the deceleration of the vehicle so that the working fluid pressure to FL to 1RR is reduced.
To control. As a result, the amount of braking force applied to the vehicle by the motor generator MG in the regenerative operation state is offset by the amount of reduction of the braking force corresponding to the reduction of the working fluid pressure. The braking force according to the depression amount of 3 will act.

Then, in the ABS controller 9a,
Point t₁The driver depresses the brake pedal 3 to brake.
State, for example, front left wheel W_FLWill lock up
When the pressure increase control valve 51FL is closed, the wheel of this wheel is closed.
Holds the working fluid pressure of the oil cylinder 1FL. That
And the wheel W_FLWhen the lock tendency of does not recover
t ₂Then, while operating the pump 55S, the pressure reducing control valve
53FL is the target wheel cylinder pressure and estimated wheel series
Open for a predetermined decompression time calculated based on the difference with the pressure
Together with ABS operation flag AS_FLAS_FLSet to = 1
The motor generator controller 38 and the regenerative system
The dynamic controller 9b is notified. This allows the wheel
Working fluid pressure to cylinder 1FL to master cylinder 2 side
It is refluxed and depressurized. And this decompression reduces the wheel speed.
When the degree recovers, once close the decompression control valve 53FL.
The working fluid pressure of the wheel cylinder 1FL of the corresponding wheel is maintained.
Hold and open the pressure increase control valve 51FL for a predetermined time.
Slowly increase the working fluid pressure of the corresponding wheel cylinder 1FL
It After that, repeat this operation at the time
t_Five, Time t₆, Time t₇... depressurizes for a predetermined time
I do.

On the other hand, in the regenerative braking controller 9b to which the ABS operation flag of AS _FL = 1 is notified, the regenerative coordinated control is stopped and the fail safe valve 25 of the four wheel integrated control actuator unit 5 is opened. The wheel integrated control pressure increasing control valve 30 is controlled to be open, the four wheel integrated control pressure reducing control valve 31 is controlled to be closed, and the front wheel controlling actuator unit 7 is opened to the front left and right wheel pressure reducing control switching valve 41FL. The working fluid pressure on the upstream side is supplied to the wheel cylinder 1FL without passing through the proportioning valve 43FL. This allows
The decompression control by the front wheel control actuator unit 7 is stopped, the working fluid pressure to the pressure control cylinder 16 is increased, and a working fluid pressure substantially equal to the master cylinder pressure is output, so that the four-wheel integrated control actuator is produced. The regenerative cooperative control by the unit 5 is stopped.

Further, in the motor generator controller 38, when notified from the ABS controller 9a as the ABS operation flag AS _FL = 1 the electric braking force applied by the regenerative operation of the motor generator MG is as shown in FIG. Then, the motor generator MG is driven so as to decrease with a preset inclination, and the regenerative operation of the motor generator MG is stopped soon.

[0074] Here, the in ABS controller 9a, a decompression time Tp for controlling the pressure reduction control valves 53FL to the open state, and set according to the difference between the target wheel cylinder P ^* _I pressure and the estimated wheel cylinder pressure P _I However, the first pressure reduction after the start of the anti-lock brake control, that is, the pressure reduction time Tp at the time point t ₂ is set as follows. That is, in the flowchart of FIG. 5, when the pressure reduction time Tp is a negative value in the process of step S28,
Proceeds from step S28 to step S32, at this time, because performing decompression of the first working fluid pressure at time t _2, since the previous ABS operation flag _{AS (n-1) FL =} 0, the step S32 to step S35 Transition. Then, since the regenerative coordinated pressure reduction is being performed by the four-wheel integrated control actuator unit 5 or the front-wheel control actuator unit 7, the process proceeds to step S36, and the four-wheel integrated control is performed from the pressure reduction information notified from the regenerative braking controller 9b. A pressure reduction correction time Tα (= K · V _L ) corresponding to the pressure reduction amount V _L for the front left wheel W _FL by the actuator unit 5 and the front wheel control actuator unit 7 is calculated. The decompression correction time Tα is equal to the decompression time T
It is added to p and set as a new depressurization time Tp (step S36), and the corrected depressurization amount mα corresponding to the depressurization correction time Tα is calculated and the depressurization cycle m is set (step S37).

Therefore, in the first pressure reduction after the antilock brake control is started, that is, the pressure reduction at time t ₂ , the front left wheel W _FL in the antilock brake control process.
The pressure reduction for avoiding the lock tendency of the motor and the pressure reduction for canceling the electric braking force by the motor generator MG are performed. ABS operation flag AS
At time t ₂ when _FL becomes “1” and the antilock brake control is started, the regenerative braking controller 9b stops the regenerative cooperative depressurization by the four-wheel integrated control actuator unit 5 or the front-wheel control actuator unit 7. After the time point t ₂ , the total braking force acting on the front left wheel W _FL is applied to the wheel cylinder 1FL because the electric braking force by the motor generator MG is not offset by the braking force decrease amount corresponding to the pressure reduction due to the regenerative coordinated pressure reduction. It becomes larger than the braking force corresponding to the working fluid pressure that acts. Therefore, even if the antilock brake control is performed on the basis of the estimated master cylinder pressure of the wheel cylinder 1FL, the braking force is actually increased, so that the braking force becomes excessive and proper antilock brake control is performed. I can't do it. However, the braking force equivalent due to the regenerative cooperative reduced pressure at time t _2, is offset by the first-time braking force decrease in vacuum during at time t _2, that is, in the timing chart of FIG. 6, the time t ₂ after the motor The amount equivalent to the electric braking force of the generator MG is calculated at the time points t _{3 to} t.
It is designed to be offset by the decrease in braking force due to the decompression during ₄ . Therefore, it is possible to prevent the control performance of the antilock brake control process from being deteriorated by the application of the electric braking force.

When the pressure reduction is performed again by the anti-lock brake control process at time t ₅ , the process proceeds from step S28 to step S32 in the flowchart of FIG. 5, but at this time, the previous ABS operation flag AS (n- 1) Since _FL = 1 and the pressure reduction has already been performed once, the process proceeds from step S32 to step S33, and the pressure reduction time Tp and the pressure reduction period m are not corrected.

Therefore, as shown in FIG.
The depressurization time of the depressurization performed at ₅ , t ₆ , t _7, ... Is not corrected and becomes the depressurization time that depends only on the antilock brake control processing.

Therefore, since the pressure equivalent to the electric braking force of the motor generator MG after the stop of the regenerative coordinated pressure reduction is reduced from the working fluid pressure as well as the pressure reduction in the anti-lock brake control process, the anti-braking force causes the anti-brake force to decrease. It is possible to prevent the control performance of the lock brake control processing from decreasing. In particular, at the time of the first pressure reduction after the start of the anti-lock brake control process, the amount equivalent to the electric braking force is offset, so that the influence of the electric braking force can be removed at an earlier point, and more accurately. It is possible to avoid deterioration of control performance.

Further, in the antilock brake control process, after the depressurization time Tp is calculated, the ABS operation flag ASj is set to "1" to notify the regenerative braking controller 9b. Therefore, the antilock brake control process is started. It is calculated according to the working fluid pressure based on the wheel speed at the start of the antilock brake control process or the deceleration while the working fluid pressure to the wheel cylinders 1FL to 1RR is increased due to the stop of the regenerative coordinated decompression. The working fluid pressure will be reduced according to the amount of pressure reduction,
Although the braking force tends to be excessive, the increased pressure of the working fluid pressure corresponding to the electric braking force accompanying the stop of the regenerative coordinated pressure reduction, that is, the pressure reduction equivalent to the electric braking force is included in the pressure reduction control in the antilock brake control process. Therefore, it is necessary to avoid a decrease in the controllability of the antilock brake control process due to the time difference between the start of the antilock brake control process and the recovery of the working fluid pressure due to the stop of the regenerative coordinated pressure reduction accompanying this. You can

In the above-described embodiment, the case where the anti-lock operation state is applied to the front left wheel W _FL has been described, but the same applies when the anti-lock operation state is applied to the front right wheel W _FR . Is.

Further, in the above embodiment, the case where the pressure reduction correction time Tα is calculated from the pressure reduction amount V _L for the corresponding wheel notified from the regenerative braking controller 9b has been described, but for example, the motor generator MG
The decompression correction time Tα may be calculated based on the amount of power generation.

In the above embodiment, the case where the pressure reduction correction time Tα is calculated in the antilock brake control process has been described.
The regenerative braking controller 9b may calculate the pressure reduction correction time Tα and notify the antilock control process of this.

Here, in the above embodiment, the motor generator MG and the motor generator control unit 38 correspond to the electric braking means, the wheel cylinders 1FL to 1RR correspond to the fluid pressure braking means, and the antilock brake control actuator. Unit 6 and A
The BS controller 9a corresponds to the anti-lock brake control means, the four wheel integrated control actuator unit 5 and the front wheel control actuator unit 7 correspond to the working fluid pressure control means, and step S32 and step S in FIG.
The processes of 35 to S37 correspond to the reduced pressure amount correction means.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a hybrid vehicle to which a braking force control device of the present invention is applied.

FIG. 2 is a fluid pressure circuit diagram showing an example of a brake actuator unit shown in FIG.

FIG. 3 is an explanatory diagram of the booster of FIG.

FIG. 4 is a flowchart showing an example of a processing procedure of antilock brake control processing in the ABS controller.

5 is a flowchart showing an example of a processing procedure of actuator control processing in the antilock brake control processing of FIG.

FIG. 6 is a timing chart for explaining the operation of the present invention.

[Explanation of symbols]

EG engine CL clutch MG motor generator CVT continuously variable transmission W _{FL to} W _RR wheel 1 _{FL to 1 RR} wheel cylinder 3 brake pedal 4 booster 5 four wheel integrated control actuator unit 6 antilock brake control actuator unit 7 front wheel control actuator Unit 9 Brake control unit 9a ABS controller 9b Regenerative braking controller 10 Brake actuator unit 30 Four wheel integrated control pressure increase control valve 31 Four wheel integrated control pressure reduction control valve 37 Engine control unit 38 Motor generator control unit 39 Continuously variable transmission control Unit 41FL, 41FR Front left and right wheel decompression control switching valve

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B60K 6/02-6/06 B60T ⁷ /12-7/22 B60T 8/00 B60T 8/32-8/96 B60L 1 / 00-3/12 B60L 7/00-13/00 B60L 15/00-15/42

Claims (3)

(57) [Claims] 1. An electric braking means for applying an electric braking force to a predetermined wheel, and a fluid pressure braking means for applying a braking force to the wheel by a working fluid pressure applied to a braking cylinder of each wheel. An anti-lock brake control unit that individually controls the working fluid pressure to the braking cylinder of each wheel according to the lock state of each wheel; and the braking when the braking force of the electric braking unit is applied. the working fluid pressure to use the cylinder and a working fluid pressure control means for the working fluid is reduced pressure portion of the electrical braking force equivalent of the electrical braking means, said electric braking means, said antilock brake control means A braking force control device configured to stop or reduce the application of the electric braking force while controlling the working fluid pressure to the braking cylinder, wherein the antilock brake control is provided. The antilock brake control means when the means for pressure reduction control the actuating fluid pressure
The amount of pressure reduction by braking force control device characterized by comprising a pressure quantity correcting means for correcting in accordance with said electrical braking force. 2. The decompression amount correction means determines the decompression amount of the working fluid pressure at the first decompression control after the antilock brake control is started by the antilock brake control means by the electrical control at the start of the antilock brake control. The braking force control device according to claim 1, wherein the braking force control device is configured to perform correction according to power. 3. The decompression amount correction means is adapted to estimate the electric braking force from a reduction amount of the working fluid pressure by the working fluid pressure control means. The braking force control device described.