JP5716331B2 - Braking device for vehicle - Google Patents

Description

  The present invention relates to a vehicle braking device that generates brake fluid pressure by operating a brake operation member of a vehicle and supplies the brake fluid pressure to a wheel brake.

Conventionally, as a vehicle braking device, the hydraulic pressure generated by a hydraulic pump is regulated based on the amount of operation of the brake pedal, and the regulated hydraulic pressure is supplied to the wheel brake to impart braking force to the wheel. The related art is known (for example, see Patent Document 1).
According to the vehicle braking device disclosed in Patent Document 1, since the hydraulic pressure is supplied to the wheel brake according to the target hydraulic pressure calculated based on the operation amount of the brake pedal, the hydraulic pressure applied to the wheel according to the vehicle environment. The braking force of the brake can be controlled appropriately.
In recent years, with the spread of hybrid vehicles and electric vehicles, the demand for regenerative cooperative control for braking wheels by using both regenerative braking and hydraulic braking is increasing. The vehicular braking device disclosed in Patent Document 1 can freely change the braking force of the hydraulic brake on the wheels according to the state of the vehicle, and therefore can be well harmonized with regenerative braking.

JP 2007-38698 A

  In the above-described vehicle brake device according to the prior art, the adjusted hydraulic pressure is supplied to a system of wheel brakes, and the hydraulic pressure is applied to the rear of the pressurizing piston to move the pressurizing piston into the cylinder. The hydraulic pressure generated thereby is supplied to another system of wheel brake. For this reason, a predetermined interval is formed between the front end of the input piston and the rear end of the pressure piston so that the input piston connected to the brake pedal does not directly contact the pressure piston. Has been.

Therefore, in the above-described vehicular braking device according to the prior art, when the hydraulic pump fails, even if the brake pedal is operated, the wheel brake is controlled as long as the input piston does not move to fill the predetermined interval. Power is not applied, and the invalid stroke of the brake pedal increases.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicular braking device that can reduce the invalid stroke of a brake operation member at the time of failure.

In order to solve the above-described problem, the structural feature of the invention of the vehicular braking apparatus according to claim 1 is that a master hydraulic pressure chamber is formed by a cylinder portion and a master piston movable in the cylinder portion by operation of a brake operation member. The master hydraulic pressure chamber is connected to the wheel cylinder, and the master piston moves in the cylinder portion, thereby generating a hydraulic pressure in the master hydraulic pressure chamber in accordance with the operation amount of the brake operating member, and braking force on the wheels. In the vehicular braking device that suppresses an increase in the hydraulic pressure applied to the wheel cylinder until the operation amount of the brake operation member reaches the first predetermined value, the rear side of the master piston is provided. A drive source for supplying a drive hydraulic pressure to a drive chamber formed in the drive chamber to drive a master piston, a housing having a predetermined capacity, and a housing The partition wall is closely fitted and movable in the housing, and a storage chamber is formed by the end surface on one side of the partition wall and the housing, and a back pressure chamber is formed by the end surface on the other side of the partition wall and the housing. It formed, together with the reservoir is connected to the master chamber, an absorbent reservoir back pressure chamber is connected to the driving chamber, and a normally closed valve which is provided between the master pressure chamber and the storage chamber, normal An open adhering detection means for detecting the open adhering state of the closed valve, and when the open adhering detection means detects the open adhering state of the normally closed valve, the driving source supplies the driving hydraulic pressure to the back pressure chamber. Is to do.

  The structural feature of the invention according to claim 2 is that in the vehicular braking apparatus according to claim 1, an input piston is provided behind the master piston and connected to the brake operation member and movable in the cylinder portion. When the brake operation member is not operated, a predetermined interval corresponding to a second predetermined value in which the operation amount of the brake operation member is smaller than the first predetermined value is provided between the master piston and the input piston. The input piston moves in the cylinder united with the master piston after being advanced by a predetermined interval corresponding to the second predetermined value.

  The structural feature of the invention according to claim 3 is that in the vehicular braking apparatus according to claim 1 or 2, the liquid generated in the master hydraulic pressure chamber when the drive hydraulic pressure is supplied to the drive chamber by the drive source. The pressure is equal to the hydraulic pressure in the drive chamber.

  According to the vehicle braking device of the first aspect, the storage chamber of the absorption reservoir is connected to the master hydraulic chamber. Therefore, if the normally closed valve is opened during the period before the operation amount of the brake operating member reaches the first predetermined value, and the driving hydraulic pressure is not supplied to the driving chamber, Even if the master piston moves in the cylinder part, the brake fluid flows into the storage chamber from the master fluid pressure chamber, so that the fluid pressure in the master fluid pressure chamber is suppressed and hindered, and consequently, the application of braking force to the wheels is suppressed. The Therefore, when the vehicle braking device is applied to a braking device for a vehicle that performs regeneration, an invalid stroke region of a brake operation member that suppresses hydraulic braking can be formed in initial braking, and regenerative braking is suitably coordinated. The regeneration efficiency can be improved.

  Here, as described above, it is desirable that the invalid stroke is reduced when the electric system fails. In this regard, in the first aspect of the present invention, since the normally closed valve is provided between the master hydraulic chamber and the storage chamber, when the vehicle power supply fails, the normally closed valve is closed. The brake fluid is prevented from flowing from the master hydraulic pressure chamber into the storage chamber. Thereby, since the suppression of the increase in the hydraulic pressure in the master hydraulic pressure chamber due to the inflow of the brake fluid into the storage chamber is restricted, the invalid stroke at the time of failure of the electric system can be reduced.

Further, if the hydraulic pressure control in the driving chamber by the driving source is performed, even if the normally closed valve is fixed in the open state (hereinafter referred to as “open fixing of the normally closed valve”), depending on the driving hydraulic pressure introduced into the back pressure chamber, The brake fluid is suppressed from flowing into the storage chamber from the master hydraulic pressure chamber, and the hydraulic pressure can be increased in the master hydraulic pressure chamber. Thereby, the invalid stroke when the normally closed valve is stuck open can be reduced.
In addition, since the hydraulic brake can be started only by generating the drive hydraulic pressure regardless of the state of the normally closed valve, the vehicle braking device with a simple configuration and control method can be provided.

According to the vehicle braking device of the second aspect, the input piston that is connected to the brake operation member and is movable in the cylinder portion is provided behind the master piston, and the brake operation member is not operated. In addition, a predetermined interval corresponding to a second predetermined value in which the operation amount of the brake operation member is smaller than the first predetermined value is provided between the master piston and the input piston.
Thus, in the initial braking, until the operation amount of the brake operation member reaches the second predetermined value, even if the input piston moves forward in the cylinder portion, it does not come into contact with the master piston. No hydraulic pressure is generated.

Therefore, since the part of the invalid stroke area of the brake operation member can be handled by the interval between the master piston and the input piston, the absorption reservoir can be reduced in size accordingly.
In addition, since the region where the brake fluid pressure is not generated can be formed by the combination of the capacity of the absorption reservoir and the distance between the master piston and the input piston, it is possible to generate a degree of design freedom for each.

According to the vehicle braking device of the third aspect, when the driving hydraulic pressure is supplied to the driving chamber by the driving source, the hydraulic pressure generated in the master hydraulic pressure chamber becomes equal to the hydraulic pressure in the driving chamber and is absorbed. Since the fluid pressure in the reservoir chamber and the fluid pressure in the back pressure chamber are equal to each other, the brake fluid from the master fluid pressure chamber to the absorption reservoir is not moved even when the normally closed valve is open. Inflow can be reliably prevented.
Note that the hydraulic pressure generated in the master hydraulic pressure chamber is equal to the hydraulic pressure in the drive chamber not only when both hydraulic pressures are exactly equal, but also to prevent inflow of brake fluid from the master hydraulic pressure chamber to the absorption reservoir. If there is an effect that can be achieved, the case where the hydraulic pressures of both are slightly different is included.

The block diagram which showed the control system for vehicles by one Embodiment of this invention The figure which showed typically the hydraulic brake device shown in FIG. The figure which showed the state at the time of the initial stage braking of the hydraulic brake device shown in FIG. The figure which showed the state by which hydraulic braking was started in the hydraulic brake device shown in FIG. The figure which showed the correlation of the amount of brake operation and braking force in the vehicle control system shown in FIG. The figure which showed the flowchart of other embodiment of this invention

An embodiment in which the vehicle brake device according to the present invention is applied to a hybrid vehicle will be described with reference to FIGS. FIG. 1 is a schematic diagram showing the configuration of the hybrid vehicle, and FIG. 2 is a schematic diagram showing the configuration of a hydraulic brake device B (corresponding to the vehicle brake device of the present invention) of the vehicle brake device.
As shown in FIG. 1, the hybrid vehicle is a vehicle that drives driving wheels, for example, left and right front wheels FL, FR, by a hybrid system. The hybrid system is a power train that uses a combination of two types of power sources, the engine 11 and the motor 12. In the case of the present embodiment, the parallel hybrid system is a system in which wheels are directly driven by both the engine 11 and the motor 12. In addition to this, there is a serial hybrid system, in which wheels are driven by a motor 12, and the engine 11 functions as a power source for power generation. The present invention is also applicable to a serial hybrid system.

In a hybrid vehicle equipped with this parallel hybrid system, the driving force of the engine 11 is transmitted to the driving wheels (the left and right front wheels FL, FR in this embodiment) via the power split mechanism 13 and the power transmission mechanism 14. The driving force of the motor 12 is transmitted to the driving wheels via the power transmission mechanism 14.
The power split mechanism 13 appropriately splits the driving force of the engine 11 into a vehicle driving force and a generator driving force. The power transmission mechanism 14 appropriately integrates the driving forces of the engine 11 and the motor 12 according to traveling conditions and transmits them to the driving wheels. The power transmission mechanism 14 adjusts the driving force ratio transmitted between the engine 11 and the motor 12 between 0: 100 and 100: 0. The power transmission mechanism 14 has a speed change function.

  The motor 12 assists the output of the engine 11 and increases the driving force. On the other hand, the motor 12 generates power when the vehicle is braked and charges the battery 17. The generator 15 generates power based on the output of the engine 11 and has a starter function when starting the engine. The motor 12 and the generator 15 are electrically connected to the inverter 16, respectively. The inverter 16 is electrically connected to a battery 17 serving as a DC power source. The inverter 16 converts the AC voltage input from the motor 12 and the generator 15 into a DC voltage and supplies it to the battery 17. A DC voltage is converted into an AC voltage and output to the motor 12 and the generator 15.

In the present embodiment, the regenerative brake device A is constituted by the motor 12, the inverter 16 and the battery 17, and the regenerative brake device A is in a brake operation state detected by the pedal stroke sensor 22a and the pedal depression force sensor 22b. The regenerative braking force based on this is generated on one of the wheels FL, FR, RL, RR (in this embodiment, left and right front wheels FL, FR driven by the motor 12 as a drive source).
The engine 11 is controlled by an engine ECU (electronic control unit) 18. The engine ECU 18 outputs an opening degree command to an electronic control throttle according to an engine output request value from a hybrid ECU (electronic control unit) 19 described later. Adjust the rotation speed.

An inverter 16 is connected to the hybrid ECU 19 so that they can communicate with each other. The hybrid ECU 19 derives necessary engine output, electric motor torque, and generator torque from the accelerator opening and shift position (calculated from a shift position signal input from a shift position sensor not shown), and the derived engine output request value Is transmitted to the engine ECU 18 to control the driving force of the engine 11, and the motor 12 and the generator 15 are controlled through the inverter 16 in accordance with the derived electric motor torque request value and generator torque request value.
The hybrid ECU 19 is connected to a battery 17 and monitors the charge state, the charge current, and the like of the battery 17. Further, the hybrid ECU 19 is also connected to an accelerator opening sensor (not shown) that is assembled to an accelerator pedal (not shown) and detects the accelerator opening of the vehicle, and inputs an accelerator opening signal from the accelerator opening sensor. ing.

The hybrid vehicle also includes a hydraulic brake device B that directly applies a hydraulic braking force to each wheel FL, FR, RL, RR to brake the vehicle. The hydraulic brake device B includes a master cylinder 3 that generates a hydraulic pressure corresponding to an operation amount of the brake pedal 22, a reservoir tank 23 that stores the brake fluid and supplies the brake fluid to the master cylinder 3, and the master cylinder 3. And a wheel actuator WC1 to WC4 attached to each wheel FL, FR, RL, RR, and a brake actuator D that forms a control hydraulic pressure.
Further, wheel speed sensors Sfl, Sfr, Srl, Srr are attached to the wheels FL, FR, RL, RR, respectively, and the detected values are inputted to the brake ECU 21, and the control hydraulic pressure of the brake actuator D is controlled. Used for forming.

  The hydraulic brake device B transmits a depression operation of the brake pedal 22 (corresponding to a brake operation member) to the master cylinder 3 by the push rod 24, and the hydraulic pressure corresponding to the operation amount of the brake pedal 22 is transmitted by the master cylinder 3. The generated hydraulic pressure is applied to the wheel cylinders WC1, WC2, WC3, WC4 of the wheels FL, FR, RL, RR connected via the brake actuator D, so that the wheels FL, FR, RL , A hydraulic braking force corresponding to the hydraulic pressure generated in RR is generated.

  The brake pedal 22 is provided with a pedal stroke sensor 22a that detects a brake pedal stroke caused by depression of the brake pedal 22, and a pedal depression sensor 22b that detects a reaction force received by the brake pedal 22. The pedal stroke sensor 22a and the pedal depression force sensor 22b are connected to the brake ECU 21 so that a detection signal is transmitted to the brake ECU 21.

The brake ECU 21 is connected to a vehicle body acceleration sensor 25 that detects the acceleration of the vehicle, and a detection signal is transmitted to the brake ECU 21.
The brake ECU 21 is connected to the hybrid ECU 19 and the brake actuator D, and controls the operation of the brake actuator D based on the state of the regenerative brake device A input from the hybrid ECU 19.

  Next, the master cylinder 3 will be described with reference to FIG. In the description, the left side in FIG. 2 (the direction in which the push rod 24 moves when the brake pedal 22 is depressed) is in front of the master cylinder 3 and the right side (the direction in which the push rod 24 moves when the brake pedal 22 returns). Will be described as the rear of the master cylinder 3. The master cylinder 3 is formed by a tandem master cylinder having a primary chamber PC and a secondary chamber SC. A cylinder portion 311 is formed inside the cylinder body 31 of the master cylinder 3.

The secondary piston 33 is formed in a substantially U-shaped cross section and is accommodated in the cylinder portion 311 so as to face the bottom portion of the cylinder portion 311. The outer peripheral surface of the secondary piston 33 is in contact with the first seal cup 34 a and the second seal cup 34 b provided on the inner peripheral surface of the cylinder portion 311, and is slidable and liquid-tightly fitted to the cylinder portion 311. doing. Thereby, it seals with the 1st seal cup 34a, and the secondary chamber SC is formed of the cylinder part 311 and the secondary piston 33. A first communication port 331 that connects the outer peripheral surface of the secondary piston 33 and the secondary chamber SC passes through the front portion of the secondary piston 33.
A secondary spring 35 is elastically interposed between the recess 332 of the secondary piston 33 and the bottom of the cylinder portion 311. A stopper bolt (not shown) is screwed onto the cylinder body 31 to receive the rear portion of the secondary piston 33 that receives the urging force from the secondary spring 35.

  A primary piston 36 (corresponding to the master piston of the present invention) is movably accommodated in the cylinder portion 311 so as to be positioned behind the secondary piston 33. The primary piston 36 has a substantially H-shaped cross section, and its outer peripheral surface comes into contact with a third seal cup 34 c and a fourth seal cup 34 d provided on the inner peripheral surface of the cylinder portion 311, and On the other hand, it is liquid-tightly fitted.

  Thereby, it seals by the 2nd seal cup 34b and the 3rd seal cup 34c, and primary chamber PC (corresponding to the master hydraulic pressure room of the present invention) is formed by cylinder part 311, secondary piston 33, and primary piston 36. . A second communication port 361 that connects the outer peripheral surface of the primary piston 36 and the primary chamber PC passes through the front portion of the primary piston 36.

A spring support portion 333 protrudes from the rear end portion of the secondary piston 33, and one end portion of the primary spring 40 is engaged with the spring support portion 333. The other end of the primary spring 40 is in contact with the recess 362 of the primary piston 36, and the primary spring 40 is elastically interposed between the secondary piston 33 and the primary piston 36.
A support wall 312 protrudes radially inward from the cylinder body 31 behind the primary piston 36. The primary piston 36 that receives a rearward urging force from the primary spring 40 is positioned when its rear end abuts against the front end surface of the support wall 312 when the brake pedal 22 is not operated (shown in FIG. 2).

A sliding hole 312a passes through the support wall 312, and a first seal ring 41a is attached to the sliding hole 312a. An input piston 43 is inserted into the cylinder body 31 from the rear, and a small diameter portion 431 of the input piston 43 is movably fitted in the sliding hole 312a. The outer peripheral surface of the input piston 43 is fluid-tightly fitted to the sliding hole 312a by contacting the first seal ring 41a.
The small-diameter portion 431 faces the rear end of the primary piston 36, is sealed by the fourth seal cup 34d and the first seal member 41a, and is driven behind the primary piston 36 by the cylinder body 31, the primary piston 36, and the input piston 43. DC is formed.

The input piston 43 is formed with a small-diameter portion 431 at the front, a large-diameter portion 432 at the center in the axial direction, and a small-diameter connecting portion 433 at the rear. In the cylinder body 31, an input cylinder 313 (including the cylinder portion 311 and included in the cylinder portion of the present invention) is formed so as to be positioned behind the support wall 312. A large diameter portion 432 of the input piston 43 is slidably fitted to the input cylinder 313. A second seal ring 41 b is mounted on the outer peripheral surface of the large diameter portion 432, and the large diameter portion 432 is fitted in a liquid-tight manner with respect to the input cylinder 313.
As a result, the first seal member 41 a and the second seal member 41 b are sealed, and the input cylinder 313 and the input piston 43 form an annular reaction force chamber RC.

Further, the outer peripheral surface of the connecting portion 433 of the input piston 43 is slidably fitted into an insertion hole 315 formed in the rear end wall 314 of the cylinder body 31. The connecting portion 433 is in contact with the third seal ring 41c mounted in the insertion hole 315 and is fitted in the insertion hole 315 in a liquid-tight manner. Thus, the second sealing ring 41 b and the third sealing ring 41 c are sealed, and the compensation chamber CC is formed by the input cylinder 313 and the input piston 43 behind the large diameter portion 432.
Further, in the input piston 43, a both-part connecting hole 434 that opens to the front end portion of the small diameter portion 431 and the outer peripheral surface of the connecting portion 433 is formed. As shown in FIG. 2, the drive chamber DC and the compensation chamber CC are communicated with each other through the both-part connecting holes 434.

An engagement concave portion 435 is formed in the rear portion of the input piston 43, and the push rod 24 described above is attached to the engagement concave portion 435 so as to be swingable and not dropout. Thereby, the input piston 43 is connected to the brake pedal 22 via the push rod 24. The input piston 43 is pulled rearward under the urging force of a return spring (not shown) attached to the brake pedal 22, and the rear end surface of the large diameter portion 432 comes into contact with the rear end wall 314 of the cylinder body 31.
When the large-diameter portion 432 contacts the rear end wall 314, positioning is performed when the brake pedal 22 is not operated and the input piston 43 is at the rearmost position. In the state where the input piston 43 is located at the rearmost position, a gap S ₀ is formed between the front end portion of the input piston 43 and the rear surface of the primary piston 36 facing the input piston 43 (shown in FIG. 2).

A pair of bosses 316a and 316b to which the above-described reservoir tank 23 is attached are formed on the upper portion of the cylinder body 31. In addition, a pair of supply ports 317 a and 317 b that allow the supply of brake fluid from the reservoir tank 23 to the secondary chamber SC and the primary chamber PC pass through the cylinder body 31.
Further, the cylinder body 31 is provided with output ports 318a and 318b for connecting the secondary chamber SC and the primary chamber PC to the ABS actuator 5 (described later). Further, the cylinder body 31 is formed with a power port 318c for connecting the driving chamber DC to a power hydraulic pressure source 7 (described later). Further, a dummy port 318 d for connecting the reaction force chamber RC to the power hydraulic pressure source 7 is formed in the cylinder body 31.

  Next, the ABS actuator 5 included in the brake actuator D will be described with reference to FIG. The ABS actuator 5 is a known one for performing anti-skid control. The pressure increase control valves 51, 52, 53, and 54, which are normally open solenoid valves, and the pressure reduction control valve 55, which is a normally closed solenoid valve. , 56, 57, 58, pressure regulating reservoirs 59, 61 for accommodating brake fluid discharged from the wheel cylinders WC1, WC2, WC3, WC4, and return of the brake fluid in the pressure regulating reservoirs 59, 61 to the master cylinder 3 side The motor 62 drives the pumps 62 and 63 and the reflux pumps 62 and 63.

  A main pipe Lp, which is a brake pipe, is connected to the output port 318b that communicates with the primary chamber PC. Further, a main pipe Ls that is a brake pipe is connected to the output port 318a that communicates with the secondary chamber SC. A pair of pressure increasing lines Lp1, Lp2 are connected to the main line Lp, and the pressure increasing lines Lp1, Lp2 are connected to the wheel cylinder WC2 of the right front wheel FR and the wheel cylinder WC3 of the left rear wheel RL, respectively. . A pair of pressure increasing lines Ls1, Ls2 is connected to the main line Ls, and the pressure increasing lines Ls1, Ls2 are connected to the wheel cylinder WC1 of the left front wheel FL and the wheel cylinder WC4 of the right rear wheel RR, respectively. ing.

  Pressure increase control valves 53 and 54 are disposed in the pressure increase lines Lp1 and Lp2, respectively, and check valves 53a and 54a permitting the flow of brake fluid from the wheel cylinders WC2 and WC3 to the main line Lp. The pressure increase control valves 53 and 54 are arranged in parallel. The pressure increase control valves 53 and 54 are connected to the brake ECU 21 and are controlled to be opened and closed by the brake ECU 21.

  Further, pressure increase control valves 51 and 52 are disposed in the pressure increase lines Ls1 and Ls2, respectively, and check valves 51a and 51 that allow the flow of brake fluid from the wheel cylinders WC1 and WC4 toward the main line Ls. 52 a is arranged in parallel to the pressure increase control valves 51 and 52. The pressure increase control valves 51 and 52 are connected to the brake ECU 21 and are controlled to be opened and closed by the brake ECU 21.

A pressure reducing line Lp3 is connected to a portion of the pressure increasing line Lp1 between the pressure increasing control valve 53 and the wheel cylinder WC2. The pressure reducing line Lp3 connects the pressure increasing line Lp1 and the pressure regulating reservoir 61. A pressure reduction control valve 57 is disposed in the pressure reduction line Lp3. The pressure reduction control valve 57 is connected to the brake ECU 21 and is controlled to be opened and closed by the brake ECU 21.
Further, a pressure reducing line Lp4 is connected to a portion of the pressure increasing line Lp2 between the pressure increasing control valve 54 and the wheel cylinder WC3. The pressure reducing line Lp4 connects the pressure increasing line Lp2 and the pressure regulating reservoir 61. A pressure reducing control valve 58 is disposed in the pressure reducing line Lp4. The pressure reduction control valve 58 is connected to the brake ECU 21 and is controlled to be opened and closed by the brake ECU 21.

Further, a pressure reducing line Ls3 is connected to a portion of the pressure increasing line Ls1 between the pressure increasing control valve 51 and the wheel cylinder WC1. The pressure reducing line Ls3 connects the pressure increasing line Ls1 and the pressure regulating reservoir 59. A decompression control valve 55 is disposed in the decompression line Ls3. The pressure reduction control valve 55 is connected to the brake ECU 21 and is controlled to be opened and closed by the brake ECU 21.
Further, a pressure reducing line Ls4 is connected to a portion of the pressure increasing line Ls2 between the pressure increasing control valve 52 and the wheel cylinder WC4. The pressure reducing line Ls4 connects the pressure increasing line Ls2 and the pressure regulating reservoir 59. A decompression control valve 56 is disposed in the decompression line Ls4. The pressure reduction control valve 56 is connected to the brake ECU 21 and is controlled to be opened and closed by the brake ECU 21.

  The pressure regulation reservoir 61 is connected to the main pipeline Lp by a reflux pipeline Lp5. A reflux pump 63 is disposed in the reflux line Lp5. Between the pressure regulating reservoir 61 and the reflux pump 63 and between the reflux pump 63 and the main line Lp, the pressure regulating reservoir 61 is connected to the main line Lp. A pair of check valves 65a and 65b that allow the flow of the directed brake fluid are provided. The recirculation pump 63 is controlled by the brake ECU 21 to recirculate the brake fluid in the pressure regulating reservoir 61 to the main line Lp.

  Further, the pressure regulating reservoir 59 is connected to the main pipeline Ls by a reflux pipeline Ls5. A reflux pump 62 is disposed in the reflux line Ls5. Between the pressure regulating reservoir 59 and the reflux pump 62 and between the reflux pump 62 and the main line Ls, the pressure regulating reservoir 59 is connected to the main line Ls. A pair of check valves 64a and 64b that allow the flow of the directed brake fluid are provided. The recirculation pump 62 is controlled by the brake ECU 21 to recirculate the brake fluid in the pressure regulating reservoir 59 to the main line Ls.

  The ABS actuator 5 is controlled by the brake ECU 21 and adjusts the hydraulic pressure generated by the master cylinder 3 based on the detected values of the wheel speed sensors Sfl, Sfr, Srl, Srr (shown in FIG. 1), and the wheel cylinders WC1, WC2. , WC3, WC4 to execute anti-skid control. Since the ABS actuator 5 is known and is not the subject of the present invention, further detailed description is omitted.

  On the other hand, the power hydraulic pressure source 7 included in the brake actuator D includes a reservoir 71, a pair of power pumps 72 and 73 that suck and discharge the brake fluid in the reservoir 71, a motor 74 that drives the power pumps 72 and 73, Part of the brake fluid discharged from the power pumps 72 and 73 is returned to the reservoir 71, and linear pressure reducing valves 75 and 76 which are electromagnetic linear valves for adjusting the pressure are provided.

  The power pump 72 on one side is connected to the reservoir 71 by a suction line PL1. An output line PL3 is connected to the discharge port of the power pump 72, and the output line PL3 is connected to the dummy port 318d of the master cylinder 3 described above. The power pump 72 is connected to the brake ECU 21 and is controlled in operation by the brake ECU 21. Further, a pressure sensor 77 is disposed in a portion of the output line PL3 between the power pump 72 and the dummy port 318d. The value detected by the pressure sensor 77 is input to the brake ECU 21.

  A discharge line PL5 is connected to a portion of the output line PL3 between the power pump 72 and the dummy port 318d. The discharge line PL5 connects the output line PL3 to the reservoir 71. A linear pressure reducing valve 75 is disposed in the output line PL5. The linear pressure reducing valve 75 is connected to the brake ECU 21 and controlled by the brake ECU 21. In addition, a check valve 75a that allows the flow of brake fluid from the reservoir 71 to the dummy port 318d is disposed in parallel to the linear pressure reducing valve 75 in the discharge line PL5. A reaction force power system that supplies the generated hydraulic pressure to the reaction force chamber RC is configured by the element configuration such as the power pump 72 described above.

  On the other hand, the power pump 73 on the other side is connected to the reservoir 71 by a suction line PL2. An output line PL4 is connected to the discharge port of the power pump 73, and the output line PL4 is connected to the power port 318c. The power pump 73 is connected to the brake ECU 21 and the operation is controlled by the brake ECU 21. Further, a pressure sensor 78 is disposed in a portion of the output line PL4 between the power pump 73 and the power port 318c. A value detected by the pressure sensor 78 is input to the brake ECU 21.

  A discharge line PL6 is connected to a portion of the output line PL4 between the power pump 73 and the power port 318c. The discharge line PL6 connects the output line PL4 to the reservoir 71. A linear pressure reducing valve 76 is disposed in the output line PL6. The linear pressure reducing valve 76 is connected to the brake ECU 21 and controlled by the brake ECU 21. In addition, a check valve 76a that allows the flow of brake fluid from the reservoir 71 to the power port 318c is disposed in parallel to the linear pressure reducing valve 76 in the discharge pipe PL6. A driving force power system (corresponding to the driving source of the present invention) that supplies the generated hydraulic pressure to the driving chamber DC is configured by the element configuration such as the power pump 73 described above.

  The brake ECU 21 controls the power pump 72 and the linear pressure reducing valve 75 based on the detected value by the pedal stroke sensor 22a, the detected value by the pedal depression force sensor 22b, and the detected value by the pressure sensor 77. In the reaction force power system of the power hydraulic pressure source 7, the power pump 72 sucks and discharges the brake fluid in the reservoir 71 and returns a part of the brake fluid discharged through the linear pressure reducing valve 75 to the reservoir 71. By adjusting the pressure, the reaction force drive hydraulic pressure corresponding to the stroke amount of the brake pedal 22 is generated. The reaction force drive hydraulic pressure is applied to the reaction force chamber RC to urge the input piston 43 of the master cylinder 3 rearward to generate a reaction force corresponding to the stroke amount of the brake pedal 22.

  Further, the brake ECU 21 controls the power pump 73 and the linear pressure reducing valve 76 based on the detection value by the pedal stroke sensor 22a and the detection value by the pressure sensor 78. In the driving force power system of the power hydraulic pressure source 7, the power pump 73 sucks and discharges the brake fluid in the reservoir 71 and returns a part of the brake fluid discharged via the linear pressure reducing valve 76 to the reservoir 71. Thus, the servo drive hydraulic pressure (corresponding to the drive hydraulic pressure of the present invention) corresponding to the stroke amount of the brake pedal 22 is generated.

The servo drive hydraulic pressure is applied to the drive chamber DC to advance the primary piston 36 in the cylinder portion 311. As a result, the brake fluid pressure corresponding to the stroke amount of the brake pedal 22 is generated in the primary chamber PC and the secondary chamber SC of the master cylinder 3 to apply a braking force to the wheels FL, FR, RL, RR.
As apparent from the above description, in the power hydraulic pressure source 7, the reaction force driving hydraulic pressure and the servo driving hydraulic pressure are controlled independently of each other, and both can be adjusted to different values.

  As shown in FIG. 2, the outflow pipe LC is connected between the main pipe Lp and the output pipe PL4 so as to connect the primary chamber PC, the driving chamber DC, and the driving power system of the power hydraulic pressure source 7. An absorption reservoir 91 is formed in the outflow pipe LC. The absorption reservoir 91 is provided in a reservoir case 911 (corresponding to the housing of the present invention) having a predetermined capacity so that the movable body 912 can move.

  The moving body 912 (corresponding to the partition wall of the present invention) is liquid-tightly fitted to the reservoir case 911, so that the storage chamber 913 is defined by the end surface (upper surface in FIG. 2) and the reservoir case 911. The back pressure chamber 914 is formed by the other end face (the lower face in FIG. 2) and the reservoir case 911. As shown in FIG. 2, the storage chamber 913 is connected to the primary chamber PC of the master cylinder 3, and the back pressure chamber 914 is connected to the drive chamber DC. An elastic spring 915 is interposed between the moving body 912 and the reservoir case 911, and the moving body 912 is biased toward the storage chamber 913 by the elastic spring 915.

  A cut valve 92 (corresponding to the normally closed valve of the present invention), which is a normally closed electromagnetic valve, is interposed between the primary chamber PC and the storage chamber 913 of the outflow pipe LC. The cut valve 92 is connected to the brake ECU 21 and is controlled to be opened and closed by the brake ECU 21. In the outflow pipe LC, a check valve 92 a that allows the flow of brake fluid from the storage chamber 913 to the primary chamber PC is disposed in parallel to the cut valve 92. The check valve 92a opens when the cut valve 92 is closed and the brake fluid pressure in the primary chamber PC decreases, and has a function of returning the brake fluid in the storage chamber 913 to the primary chamber PC side.

In the hydraulic brake device B, during initial braking, an increase in brake hydraulic pressure applied to the wheel cylinders WC1, WC2, WC3, and WC4 is suppressed until the stroke of the brake pedal 22 reaches the first predetermined value. . Until the stroke of the brake pedal 22 reaches the first predetermined value, braking force is applied to the driving wheels FL and FR only by regenerative braking by the regenerative braking device A.
If the first predetermined value related to the stroke amount of the brake pedal 22 in the present embodiment is described in association with the mechanical configuration of the hydraulic brake device B, the cylinder portion 311 of the input piston 43 corresponding to the first predetermined value will be described. The movement amount is set to St = S ₀ + T (the stroke amount of the brake pedal 22 is converted into the movement amount of the input piston 43 by the lever ratio of the brake pedal 22).

As is clear from the foregoing, the movement amount S ₀ of the input piston 43 is the movement amount from the start of the operation of the brake pedal 22 until the front end of the input piston 43 comes into contact with the rear surface of the primary piston 36. Applicable. Therefore, the stroke amount of the brake pedal 22 when the front end of the input piston 43 comes into contact with the rear surface of the primary piston 36 corresponds to the second predetermined value of the present invention, and corresponds to the stroke amount of the brake pedal 22 at that time. movement amount S ₀ of the input piston 43, corresponds to a predetermined distance of the present invention. Of course, it goes without saying that the relationship is first predetermined value> second predetermined value.

  Further, the movement amount T of the input piston 43 is the movement amount from when the front end of the input piston 43 comes into contact with the rear surface of the primary piston 36 until the servo hydraulic pressure is generated by the power hydraulic pressure source 7. Applicable. The generation of the servo drive hydraulic pressure by the power hydraulic pressure source 7 is always set before the storage chamber 913 of the absorption reservoir 91 is fully filled with the brake fluid.

  The first predetermined value related to the stroke of the brake pedal 22 described above is not an invariable value, but changes depending on the state of regenerative braking by the regenerative braking device A. That is, the regenerative braking ability changes in real time within the range of the maximum value set by the vehicle specifications, and the stroke of the brake pedal 22 when the hydraulic brake is started according to the changing regenerative braking ability. The amount (first predetermined value) changes.

Actually, the currently required vehicle deceleration is calculated from the stroke amount and the depression force of the brake pedal 22. On the other hand, if it is determined that the required vehicle deceleration can be obtained only by the regenerative braking by the regenerative braking device A, the braking force is applied to the wheels FL, FR, RL, RR by the hydraulic brake device B. I will not. Further, if it is determined that the necessary vehicle deceleration cannot be obtained only by regenerative braking, the braking force to the wheels FL, FR, RL, RR is supplemented by hydraulic braking.
Therefore, when the regenerative braking is functioning sufficiently, the vehicle is traveling at a high speed, the shift position is in the N range, or the regenerative braking does not function sufficiently due to the battery 17 being overcharged. In this case, the first predetermined value is decreased.

  Next, the operation of the hydraulic brake device B will be described with reference to FIGS. First, when the driver of the vehicle starts the stroke of the brake pedal 22, the input piston 43 is urged by the push rod 24 and moves forward in the cylinder portion 311. However, when the brake ECU 21 determines that the stroke amount of the brake pedal 22 is less than the first predetermined value based on the signal from the pedal stroke sensor 22a, the power pump 73 is not operated and the power hydraulic pressure source 7 is not operated. No servo drive hydraulic pressure is generated by the drive power system.

As described above, since the front end of the input piston 43 and the rear surface of the primary piston 36 do not contact each other until the amount of movement of the input piston 43 reaches S ₀ , the primary piston 36 does not move forward in the cylinder portion 311. Thus, no hydraulic pressure is generated in the primary chamber PC. Further, since no hydraulic pressure is generated in the primary chamber PC, the secondary piston 33 does not move forward, and no hydraulic pressure is generated in the secondary chamber SC. Therefore, the brake fluid pressure is not supplied to the wheel cylinders WC1, WC2, WC3, WC4.
As described above, when the hydraulic brake is not applied to the wheels FL, FR, RL, and RR, only the regenerative braking by the regenerative braking device A is performed on the driving wheels FL and FR.
Further, at this time, the volume of the drive chamber DC decreases as the input piston 43 advances, and the amount of decrease in the volume of the drive chamber DC and the amount of increase in the volume of the compensation chamber CC as the input piston 43 advances. Therefore, the brake fluid in the drive chamber DC only moves to the compensation chamber CC via the two connecting holes 434 by the advance of the input piston 43, and the drive chamber DC and the compensation chamber CC There is no generation of hydraulic pressure.

  On the other hand, when the brake pedal 22 is stroked, the brake ECU 21 uses the brake pedal 22 in the reaction force power system of the power hydraulic pressure source 7 based on the detected values by the pedal stroke sensor 22a, the pedal depression force sensor 22b, and the pressure sensor 77. The reaction force drive hydraulic pressure corresponding to the stroke amount is generated and supplied to the reaction force chamber RC. The reaction force drive hydraulic pressure supplied to the reaction force chamber RC urges the input piston 43 rearward to generate a reaction force corresponding to the stroke amount of the brake pedal 22.

When the input piston 43 moves forward by the movement amount S ₀ or more, the front end of the input piston 43 comes into contact with the rear surface of the primary piston 36. Thereafter, until the stroke amount of the brake pedal 22 reaches the first predetermined value (in other words, until the movement amount of the input piston 43 reaches St described above), the servo hydraulic pressure is supplied by the power hydraulic pressure source 7. The primary piston 36 is directly pressed by the input piston 43, and both move forward together (shown in FIG. 3). As a result, the second communication port 361 of the primary piston 36 passes through the third seal cup 34 c and the primary chamber PC is shut off from the reservoir tank 23.

When the front end of the input piston 43 comes into contact with the rear surface of the primary piston 36, the brake ECU 21 opens the cut valve 92. Therefore, the brake in the primary chamber PC is moved forward by the primary piston 36 in the cylinder portion 311. The liquid flows into the storage chamber 913 of the absorption reservoir 91 against the urging force of the elastic spring 915. Thus, no hydraulic pressure is generated in the primary chamber PC regardless of the forward movement of the primary piston 36. Further, since no hydraulic pressure is generated in the primary chamber PC, the secondary piston 33 does not move forward, and no hydraulic pressure is generated in the secondary chamber SC. Therefore, no hydraulic brake is applied to the wheels FL, FR, RL, and RR.
At this time, it is desirable to make the set load of the secondary spring 35 larger than the compressive load of the primary spring 40 generated by the advance of the primary piston 36.
Even in this state, only regenerative braking by the regenerative braking device A is continuously performed on the driving wheels FL and FR.

  When the stroke amount of the brake pedal 22 further increases, the regenerative braking ability by the regenerative braking device A reaches the upper limit, and the brake ECU 21 determines that the stroke amount of the brake pedal 22 has reached the first predetermined value, the pedal stroke Based on the detection value by the sensor 22a and the detection value by the pressure sensor 78, in the driving power system of the power hydraulic pressure source 7, a servo driving hydraulic pressure corresponding to the stroke amount of the brake pedal 22 is generated, and the servo driving fluid is generated. Pressure is supplied to the drive chamber DC (shown in FIG. 4).

  The servo drive hydraulic pressure supplied to the drive chamber DC urges the primary piston 36 of the master cylinder 3 to advance the primary piston 36 in the cylinder portion 311. When the servo drive hydraulic pressure is supplied to the drive chamber DC, the primary piston 36 is separated from the input piston 43 and moves forward in the cylinder portion 311. At this time, since the servo driving hydraulic pressure of the power hydraulic pressure source 7 is also supplied to the back pressure chamber 914 of the absorption reservoir 91 via the outflow line LC, the back pressure chamber of the moving body 912 in the reservoir case 911 is supplied. Movement in the 914 direction is prevented. Therefore, no further brake fluid flows from the primary chamber PC into the storage chamber 913.

Thereby, in the primary chamber PC of the master cylinder 3, the brake fluid pressure according to the stroke of the brake pedal 22 is generated. Further, since the hydraulic pressure is generated in the primary chamber PC, the secondary piston 33 also moves forward in the cylinder portion 311 to generate the brake hydraulic pressure in accordance with the stroke of the brake pedal 22 in the secondary chamber SC, so that the wheels FL, FR , RL, and RR are given braking force by hydraulic brake.
At this time, since the seal diameters of the third seal cup 34c and the fourth seal cup 34d with respect to the primary piston 36 are equal, the servo drive hydraulic pressure of the power hydraulic pressure source 7 supplied to the drive chamber DC and the primary chamber PC are generated. The brake fluid pressure is almost equal.
Further, when the driving power system of the power hydraulic pressure source 7 starts generating the servo driving hydraulic pressure, the cut valve 92 is closed to transfer the primary chamber PC to the storage chamber 913 of the absorption reservoir 91. The inflow of the brake fluid may be blocked.

  Further, the servo drive hydraulic pressure supplied to the drive chamber DC is also introduced into the compensation chamber CC via the both-part connecting holes 434. Accordingly, the front surface of the input piston 43 receives the servo driving hydraulic pressure in the driving chamber DC, but the pressure receiving area of the input piston 43 in the driving chamber DC and the pressure receiving pressure of the large-diameter portion 432 of the input piston 43 in the compensation chamber CC. Since the area is equal, the input piston 43 is not urged in the front-rear direction by the servo drive hydraulic pressure from the power hydraulic pressure source 7.

After the supply of servo drive hydraulic pressure to the drive chamber DC by the power hydraulic pressure source 7 is started, both regenerative braking by the regenerative braking device A and hydraulic braking by the hydraulic brake device B function.
Further, in the hydraulic brake device B, when the vehicle power supply fails, the cut valve 92 is closed, so that the brake fluid is prevented from flowing into the storage chamber 913 from the primary chamber PC.

As shown in FIG. 5, according to the hydraulic brake device B according to the above-described embodiment, regardless of the state of the regenerative braking by the regenerative brake device A, the regenerative braking force and the braking force by the hydraulic brake are always used. A stable vehicle braking force can be applied to the wheels FL, FR, RL, and RR according to the stroke amount of the brake pedal 22.
In addition, according to the state of the regenerative braking by the regenerative braking device A, the regenerative braking can always function sufficiently by suppressing the braking force by the hydraulic brake during the initial braking.

  According to the present embodiment, the storage chamber 913 of the absorption reservoir 91 is connected to the primary chamber PC, and the cut valve 92 is opened before the operation amount of the brake pedal 22 reaches the first predetermined value. The drive hydraulic pressure for servo is not supplied to the drive chamber DC. For this reason, even if the primary piston 36 moves in the cylinder portion 311 by being pressed by the input piston 43, the brake fluid flows into the storage chamber 913 from the primary chamber PC, thereby preventing an increase in hydraulic pressure. Application of braking force to FR, RL, and RR is suppressed. Therefore, in the initial braking, an invalid stroke region of the brake pedal 22 that suppresses the hydraulic brake can be formed, and the regenerative braking can sufficiently function.

  When the operation amount of the brake pedal 22 reaches the first predetermined value, the driving force power system of the power hydraulic pressure source 7 applies the servo driving hydraulic pressure formed based on the operation amount of the brake pedal 22 to the driving chamber DC. By supplying the servo drive hydraulic pressure, the back pressure chamber 914 is also supplied. For this reason, even if the cut valve 92 is not closed, the moving body 912 of the absorption reservoir 91 is prevented from moving toward the back pressure chamber 914 by the servo drive hydraulic pressure introduced into the back pressure chamber 914. Therefore, the brake fluid does not flow into the storage chamber 913 from the primary chamber PC any more, and the hydraulic pressure can be increased in the primary chamber PC according to the operation of the brake pedal 22.

  In addition, since a normally closed cut valve 92 is provided between the primary chamber PC and the storage chamber 913, when the vehicle power supply fails, the cut valve 92 is closed, so that the brake fluid is discharged. The primary chamber PC is prevented from flowing into the storage chamber 913. Therefore, even if the regenerative braking device A and the power hydraulic pressure source 7 do not function, the input piston 43 directly presses the primary piston 36, so that hydraulic pressure can be generated in the primary chamber PC, and the wheels FL, FR , RL, RR can be given a sufficient braking force.

Further, when the operation amount of the brake pedal 22 reaches the first predetermined value, the moving body 912 of the absorption reservoir 91 may move toward the back pressure chamber 914 due to the servo drive hydraulic pressure introduced into the back pressure chamber 914. Be disturbed. For this reason, even if the cut valve 92 is fixed in the open state due to the biting of foreign matter or the like, the brake fluid does not flow into the storage chamber 913 from the primary chamber PC, and depends on the operation amount of the brake pedal 22. The hydraulic pressure can be increased in the primary chamber PC.
Further, the hydraulic brake can be started only by generating the servo drive hydraulic pressure regardless of the state of the cut valve 92, so that the hydraulic brake device B having a simple configuration and control method can be obtained.

In addition, an input piston 43 that is connected to the brake pedal 22 and is movable in the cylinder portion 311 is provided behind the primary piston 36. When the brake pedal 22 is not operated, the rear surface of the primary piston 36 is provided. And a front end of the input piston 43 is provided with a predetermined interval S ₀ corresponding to a second predetermined value in which the operation amount of the brake pedal 22 is smaller than the first predetermined value.

Thereby, in the initial braking, the input piston 43 does not contact the primary piston 36 even if the input piston 43 moves forward in the cylinder portion 311 until the operation amount of the brake pedal 22 reaches the second predetermined value. No hydraulic pressure is generated in the chamber PC.
Therefore, since the part of the invalid stroke area of the brake pedal 22 can be handled by the interval S ₀ between the rear surface of the primary piston 36 and the front end of the input piston 43, the absorption reservoir 91 is downsized accordingly. be able to.
Also, an area that does not generate a brake fluid pressure, it is possible to form the combination of the distance S ₀ between the capacity and both pistons 36, 43 of the absorbent reservoir 91, it is possible to generate a degree of freedom in design, respectively.

  When servo driving hydraulic pressure is supplied to the driving chamber DC by the driving power system of the power hydraulic pressure source 7, the hydraulic pressure generated in the primary chamber PC is equal to the hydraulic pressure in the driving chamber DC. . Thereby, since the hydraulic pressure in the storage chamber 913 and the back pressure chamber 914 of the absorption reservoir 91 can be made equal to each other, even if the cut valve 92 is open, the movement of the moving body 912 can be eliminated, and the primary chamber The inflow of brake fluid from the PC to the absorption reservoir 91 can be reliably prevented.

<Other embodiments>
The present invention is not limited to the above-described embodiments, and can be modified or expanded as follows.
The present invention can be applied to any front-wheel drive vehicle, rear-wheel drive vehicle, or 4-wheel drive vehicle, and can be applied regardless of whether the brake pipe is a front-rear pipe or an X-pipe.
Further, the present invention can be applied not only to a hybrid vehicle but also to an electric vehicle (EV).

Further, the cut valve 92 may be always open when the brake pedal 22 is operated, except when the power hydraulic pressure source 7 fails.
Further, the operation amount of the brake operation member may be detected by the stroke amount of the push rod 24 or the stroke amount of the input piston 43 of the master cylinder 3.
Further, the present invention may be applied not only to a tandem master cylinder but also to a single master cylinder.

  In the above-described embodiment, the servo drive hydraulic pressure is generated when the stroke amount of the brake pedal 22 reaches the first predetermined value. However, the stroke amount of the brake pedal 22 is the first predetermined value. However, the hydraulic pressure may be generated in the wheel cylinders WC1, WC2, WC3, and WC4 by closing the cut valve 92 without generating the servo driving hydraulic pressure. Then, an open sticking detection means for detecting the open sticking state of the cut valve 92 is provided, and the servo drive hydraulic pressure is generated when the open sticking detection means detects that the cut valve 92 is in the open sticking state. You may make it carry out (shown in FIG. 6). As the open adhesion detecting means, when the actual vehicle deceleration (detected by the vehicle body acceleration sensor 25) and the actual hydraulic pressure of the primary chamber PC in the operation state of the brake pedal 22 are smaller than their expected values by a predetermined value or more. It is possible to detect that the cut valve 92 is fixed open.

Based on FIG. 6, differences between the above-described other embodiments and the embodiment shown in FIGS. 1 to 5 will be described. In step S601, the cut valve 92 is opened and the brake pedal 22 is stroked so that no hydraulic pressure is generated in the wheel cylinders WC1, WC2, WC3, and WC4 during initial braking. Thereafter, when the brake ECU 21 determines that the stroke amount Sp of the brake pedal 22 has reached the first predetermined value (step S603), the cut valve 92 is closed (step S604), and the storage chamber is changed from the primary chamber PC to the storage chamber. Inflow of brake fluid to 913 is suppressed, and hydraulic pressure is generated in the wheel cylinders WC1, WC2, WC3, and WC4. At this point, servo drive hydraulic pressure is not generated. Thereafter, the vehicle deceleration G1 detected by the vehicle body acceleration sensor 25 is inputted (step S605), when the detected vehicle deceleration G1 is smaller than the predetermined value gv than expected G ₀ by stroke Sp of the brake pedal 22 (Step S606), the open adhering state of the cut valve 92 is detected, and the supply of servo driving hydraulic pressure to the driving chamber DC by the power hydraulic pressure source 7 is started (Step S607). As a result, the servo drive hydraulic pressure is supplied to the back pressure chamber 914 and the inflow of the brake fluid from the primary chamber PC to the storage chamber 913 is suppressed. , WC2, WC3, WC4 generate hydraulic pressure.

Further, when the stroke amount of the brake pedal 22 reaches the first predetermined value, the brake fluid flowing into the absorption reservoir 91 from the primary chamber PC exceeds the maximum capacity of the storage chamber 913, and servo drive hydraulic pressure is generated. Even if not, the hydraulic pressure may be generated in the primary chamber PC. The first predetermined value in this case is set by the movement amount S ₀ of the input piston 43, the predetermined capacity of the storage chamber 913, and the movement amount T of the input piston 43.

  In the drawing, 3 is a master cylinder, 7 is a power hydraulic pressure source (drive source), 22 is a brake pedal (brake operation member), 36 is a primary piston (master piston), 43 is an input piston, 91 is an absorption reservoir, 92 is Cut valve (normally closed valve), 311 is a cylinder portion, 911 is a reservoir case (housing), 912 is a moving body (partition wall), 913 is a storage chamber, 914 is a back pressure chamber, B is a hydraulic brake device (braking for vehicles) Device), DC is a drive chamber, FL, FR, RL, and RR are wheels, PC is a primary chamber (master hydraulic chamber), and WC1, WC2, WC3, and WC4 are wheel cylinders.

Claims (3)

A master hydraulic pressure chamber is formed by a cylinder piston and a master piston movable in the cylinder portion by operation of a brake operation member. The master hydraulic pressure chamber is connected to a wheel cylinder, and the master piston moves in the cylinder portion. By providing a master cylinder that generates a hydraulic pressure according to the operation amount of the brake operation member in the master hydraulic pressure chamber and applies a braking force to the wheel,
In the vehicle braking device that suppresses an increase in hydraulic pressure applied to the wheel cylinder until the operation amount of the brake operation member reaches a first predetermined value,
A driving source for supplying a driving hydraulic pressure to a driving chamber formed behind the master piston and driving the master piston;
A housing having a predetermined capacity, a partition wall that is fluid-tightly fitted to the housing and movable in the housing, and a storage chamber is formed by an end surface on one side of the partition wall and the housing An absorption reservoir in which a back pressure chamber is formed by the other end face of the partition wall and the housing, the storage chamber is connected to the master hydraulic pressure chamber, and the back pressure chamber is connected to the drive chamber; ,
A normally closed valve provided between the master hydraulic chamber and the storage chamber;
An open sticking detection means for detecting an open sticking state of the normally closed valve;
Equipped with a,
The vehicular braking apparatus , wherein when the open adhering detection means detects an open adhering state of the normally closed valve, the driving source supplies driving hydraulic pressure to the back pressure chamber . Behind the master piston, an input piston that is connected to the brake operation member and is movable in the cylinder part is provided,
When the brake operation member is not operated, a predetermined amount corresponding to a second predetermined value between the master piston and the input piston, the operation amount of the brake operation member being smaller than the first predetermined value. There is an interval,
The input piston is
2. The vehicular braking apparatus according to claim 1, wherein after moving forward by a predetermined interval corresponding to the second predetermined value, the vehicular braking apparatus moves together with the master piston in the cylinder portion.   The hydraulic pressure generated in the master hydraulic pressure chamber is equal to the hydraulic pressure in the driving chamber when the driving hydraulic pressure is supplied to the driving chamber by the driving source. The braking device for vehicles as described.

Images