JP4946802B2 - Braking device for vehicle - Google Patents

Description

  The present invention relates to a vehicular braking apparatus that electronically controls a braking force applied to a vehicle in response to an occupant's brake operation.

  As a vehicle braking device, an electronically controlled braking device that electrically controls a braking force of a braking device, that is, a hydraulic pressure supplied to a wheel cylinder that drives the braking device, with respect to a brake operation amount input from a brake pedal is known. It has been. An example of such a braking device is described in Patent Document 1 below.

  The vehicle braking device described in Patent Document 1 supports an input piston and a pressure piston in a cylinder so as to be movable, and allows the pressure piston to be pressed by the input piston, and a brake pedal is connected to the input piston. The pressure chambers before and after the input piston are communicated with each other through the communication passage, and the control hydraulic pressure corresponding to the operation amount of the brake pedal is regulated by the first and second linear valves to be applied to the wheel cylinder on the rear wheel side, and the second By supplying the pressure chamber to assist the pressure piston, the control hydraulic pressure generated by the movement of the pressure piston is applied to the wheel cylinder on the front wheel side.

JP 2007-203804 A

  In the above-described conventional vehicle braking device, the input piston and the pressure piston are movably supported in the cylinder at a predetermined interval, and when the occupant steps on the brake pedal, the hydraulic pressure is supplied from the accumulator to the second pressure chamber. By supplying and assisting the pressure piston, the control hydraulic pressure is supplied to each wheel cylinder through the ABS. In this case, the third pressure chamber communicates with the reservoir tank through the discharge port and the occupant depresses the brake pedal when the pressurizing cylinder is in the initial position without depressing the brake pedal. When is moved, the third pressure chamber is disconnected from the reservoir tank.

Therefore, when the pressure in the third pressure chamber increases and the pressurizing piston returns to the initial position when the pressure is increased by ABS, the third pressure chamber communicates with the reservoir tank through the discharge port, and the hydraulic pressure in the third pressure chamber becomes the reservoir pressure. It is lowered by being discharged into the tank, and the pressure piston hunts here. Then, the passenger feels uncomfortable with the brake pedal operation, and drivability deteriorates.

The present invention is intended to solve such problems, and ensures drivability by ensuring appropriate braking force and enabling highly accurate braking force control and improving the operability of braking operation. It is an object of the present invention to provide a vehicular braking device that is improved.

In order to solve the above-described problems and achieve the object, a vehicle braking apparatus according to the present invention includes an operation member that is operated by an occupant for braking, and a drive piston that is movably supported in a cylinder so that the front pressure chamber and A master cylinder capable of outputting the hydraulic pressure of the front pressure chamber by moving the drive piston by the operation member while the rear pressure chamber is partitioned, and an operation force input from the operation member to the drive piston Control pressure setting means for setting a target control pressure, a hydraulic pressure supply source, a wheel cylinder connected to the front pressure chamber to generate a braking force on the wheel, and a drive valve moved by electromagnetic force based on the target control pressure A pressure control valve capable of regulating the hydraulic pressure from the hydraulic pressure supply source and outputting it to the rear pressure chamber, and the oil in the front pressure chamber when the drive piston is in the initial position. Comprising a discharge line capable of discharging, and a shut-off valve which closes by the operation force provided the outlet line is input to the driving piston from said operating member, said shut-off valve, said rear pressure by the pressure control valve It is characterized by being closed by hydraulic pressure acting on the chamber .

  In the vehicle braking device of the present invention, the shut-off valve has a mover that closes the discharge line by an operation force input from the operation member to the drive piston, and the mover functions as a stroke simulator. It is characterized by.

  In the vehicle braking device of the present invention, the wheel cylinder on the front wheel side is connected to the front pressure chamber, and the wheel cylinder on the rear wheel side is connected to the rear pressure chamber.

According to the vehicle braking device of the present invention, the front piston chamber and the rear pressure chamber are partitioned by the drive piston being movably supported in the cylinder, and the front piston is moved by moving the drive piston by the operating member. A master cylinder capable of outputting the hydraulic pressure is provided, a wheel cylinder that generates a braking force on the wheel is connected to the front pressure chamber, and the drive valve is moved by electromagnetic force based on the target control pressure, so A pressure control valve that can regulate the hydraulic pressure and output it to the rear pressure chamber is provided, and a discharge line that discharges the hydraulic pressure in the front pressure chamber when the drive piston is in the initial position is provided. A shut-off valve that is closed by an operating force input from the member to the drive piston is provided , and the shut-off valve is closed by a hydraulic pressure acting on the rear pressure chamber by the pressure control valve . Therefore, when the occupant operates the operating member, the operating force closes the shut-off valve and shuts off the discharge line, and the hunting of the drive piston is suppressed, thereby improving the operability of the braking operation and the driver. In addition, the braking force can be improved, and an appropriate braking force can be ensured to enable highly accurate braking force control.

  Hereinafter, embodiments of a vehicle braking device according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this Example.

  FIG. 1 is a schematic configuration diagram illustrating a vehicle braking device according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a pressure control valve in the vehicle braking device according to the first embodiment.

  In the vehicular braking apparatus according to the first embodiment, as shown in FIG. 1, the master cylinder 11 is configured such that a drive piston 13 is supported in a cylinder 12 so as to be movable in the axial direction. The cylinder 12 has a cylindrical shape in which a base end portion is opened and a tip end portion is closed, and a step portion 12a is formed at a substantially intermediate position in the inner axial direction, whereby a small diameter portion 12b is formed on the base end portion side. On the other hand, a large diameter portion 12c is formed on the tip end side. A drive piston 13 is supported inside the cylinder 12 so as to be movable along the axial direction. Since the drive piston 13 has a stepped portion 13a, a small diameter piston 13b that is movably fitted to the small diameter portion 12b of the cylinder 12 and a large diameter piston 13c that is movably fitted to the large diameter portion 12c are integrated. Is formed.

  Accordingly, the drive piston 13 has a large diameter piston 13c that contacts the bottom 12d of the cylinder 12 on the forward side, while a stepped portion 13a contacts the step 12a of the cylinder 12 on the backward side. Movement stroke is regulated. The drive piston 13 has an opening 13d formed at the tip of the large-diameter piston 13c. The drive piston 13 is driven by the urging force of a reaction spring 14 stretched between the bottom 12d of the cylinder 12 and the opening 13d. The stepped portion 13a is urged and supported at an initial position where it contacts the stepped portion 12a.

  Further, the brake pedal 15 as an operation member is supported at its upper end portion by a support shaft 16 so as to be freely rotatable by a mounting bracket of a vehicle body (not shown), and a pedal 17 that can be depressed by an occupant is attached to the lower end portion. . In the brake pedal 15, a clevis 19 is attached to an intermediate portion by a connecting shaft 18. A base end portion of an operating rod 20 is connected to the clevis 19, and a distal end portion of the operating rod 20 is a connecting portion of the drive piston 13. 13e. Therefore, when the brake pedal 15 is rotated by the occupant depressing the pedal 17, the operating force is transmitted to the driving piston 13 via the operating rod 20, and the driving piston 13 resists the urging force of the reaction force spring 14. Can move forward.

The drive piston 13 is movably disposed in the cylinder 12 in this manner, so that the space of the cylinder 12 moves forward in the forward direction (leftward in FIG. 1) of the large-diameter piston 13c of the drive piston 13. ₁ is defined, and a rear pressure chamber R ₂ is defined in the backward direction (rightward in FIG. 1) of the small-diameter piston 13 b of the drive piston 13. In this case, since the driving piston 13 has a stepped portion 13a, by the pressure receiving area A ₁ of the front pressure chamber R ₁ is set larger than the pressure receiving area A ₂ of the rear pressure chamber R _2, a predetermined Servo ratio is set.

On the other hand, the front wheels FR and FL and the rear wheels RR and RL are respectively provided with wheel cylinders 21FR, 21FL, 21RR and 21RL for operating a brake device (braking device), and can be operated by an ABS (Antilock Brake System) 22. It has become. That is, one end of the first hydraulic pipe 24 is connected to the first pressure port 23 communicating with the front pressure chamber R ₁ of the master cylinder 11, and the other end of the first hydraulic pipe 24 has two Branched to hydraulic pressure supply pipes 25a and 25b and connected to wheel cylinders 21FR and 21FL of a brake device disposed on front wheels FR and FL. One end of a second hydraulic pipe 28 is connected to a second pressure port 27 that communicates with the rear pressure chamber R ₂ of the master cylinder 11 via an annular connecting passage 26. The other end is branched into two hydraulic pressure supply pipes 29a and 29b and is connected to wheel cylinders 21RR and 21RL of a brake device disposed on the rear wheels RR and RL.

  Further, base ends of hydraulic discharge pipes 30a and 30b are connected to the hydraulic supply pipes 25a and 25b branched from the first hydraulic pipe 24, and the hydraulic supply pipes 29a and 29b branched from the second hydraulic pipe 28 are connected. 29b is connected to the base ends of the hydraulic discharge pipes 31a and 31b. The hydraulic discharge pipes 30 a, 30 b, 31 a, and 31 b are connected to the reservoir tank 33 through the third hydraulic pipe 32 with the leading ends gathered.

  And in each hydraulic pressure supply pipe 25a, 25b, 29a, 29b, upstream from the connection part with each hydraulic pressure discharge pipe 30a, 30b, 31a, 31b (first, second hydraulic pipe 24, 28 side), respectively Electromagnetic pressure increasing valves 34a, 34b, 35a, 35b are arranged. In addition, electromagnetic pressure reducing valves 36a, 36b, 37a, and 37b are disposed in the hydraulic discharge pipes 30a, 30b, 31a, and 31b, respectively. The pressure increasing valves 34a, 34b, 35a, and 35b are normally open type on-off valves that are closed when power is supplied. On the other hand, the pressure reducing valves 36a, 36b, 37a, and 37b are normally closed type on-off valves that are opened when power is supplied.

  The hydraulic pump 38 can be driven by a motor 39 and is connected to the reservoir tank 33 through a pipe 40 and is connected to an accumulator 42 through a pipe 41. Accordingly, when the motor 39 is driven, the hydraulic pump 38 can supply the hydraulic oil stored in the reservoir tank 33 to the accumulator 42 to increase the pressure, and the accumulator 42 can accumulate a predetermined hydraulic pressure. In the present embodiment, a hydraulic pressure supply source is constituted by the hydraulic pump 38 and the accumulator 42.

The accumulator 42 is connected to a pressure control valve 44 through a high pressure supply pipe 43. The pressure control valve 44 adjusts the hydraulic pressure accumulated in the accumulator 42 by electromagnetic force and can output the pressure to the rear pressure chamber R ₂ of the master cylinder 11 and the wheel cylinders 21 RR and 21 RL of the ABS 22. The hydraulic pressure accumulated in the accumulator 42 can be regulated by the hydraulic pressure from the pressure chamber R ₁ and output to the rear pressure chamber R ₂ of the master cylinder 11 and the wheel cylinders 21 RR and 21 RL of the ABS 22. Therefore, the pressure control valve 44 is connected to the second hydraulic pipe 28 via the control pressure supply pipe 45, is connected to the first hydraulic pipe 24 via the external pressure supply pipe 46, and is connected to the first hydraulic pipe 24 via the pressure reduction supply pipe 47. 3 is connected to a hydraulic pipe 32.

  Here, the pressure control valve 44 described above will be described in detail. In the pressure control valve 44, as shown in FIG. 2, the housing 51 has a cylindrical shape with an opening at the bottom and a U-shaped cross section. A cylindrical upper support block 52 having a cylindrical shape is fitted to the lower portion, and a lower support block 53 having a cylindrical shape is fitted to the lower portion. Then, a cylindrical case 54 having an upper opening and a U-shaped cross section is fitted to the lower portion of the lower support block 53 so that the housing 51, the upper support block 52, the lower support block 53, and the case 54 Is in a sealed state.

  In the housing 51, a support hole 55 is formed at a substantially central portion in the vertical direction along the vertical direction, and the drive valve 56 is supported by the support hole 55 so as to be movable. The drive valve 56 has a rod shape and has a first support portion 56a formed in a cylindrical shape at the upper end portion, a first flange portion 56b formed below the first support portion 56a in the upper portion, The second support portion 56c is formed in a cylindrical shape with a predetermined length below the first flange portion 56b, and the second flange portion 56d is formed at the lower end portion. In the driving valve 56, the first support portion 56a is fitted into the support hole 52a of the upper support block 52, and the second support portion 56c is fitted into the support hole 55 of the housing 51 and the support hole 53a of the lower support block 53. As a result, the housing 51 is supported so as to be movable in the vertical direction. A return spring 57 is interposed between the housing 51 and the first flange portion 56 b of the drive valve 56, and the drive valve 56 is in contact with the lower surface of the upper support block 52. The position is biased and supported.

  Accordingly, the drive valve 56 is supported by the housing 51 so as to be movable in the vertical direction, and is urged upward by the urging force of the return spring 57, so that the first flange portion 56 b contacts the lower surface of the upper support block 52. It is positioned at the contact point.

  The upper support block 52 has a support hole 52a that opens downward, and a columnar external piston 58 is fitted in the support hole 52a so as to be vertically movable. The external piston 58 is arranged in series in the upper chamber of the drive valve 56, and the lower end surface has a spherical shape so that it can contact the upper surface of the drive valve 56.

  On the other hand, an iron suction member 59 is fixed to the lower part of the case 54 at a predetermined interval so as to face the second flange portion 56d of the drive valve 56, and on the outside of the case 54, it faces the suction member 59. And the coil 60 is wound. The suction member 59 can generate a suction force by an electromagnetic force generated by passing a current through the coil 60, and the drive valve 56 can be sucked by the suction force via the second flange 56d.

  Accordingly, the drive valve 56 is urged upward by the urging force of the return spring 57 and is positioned at a position where the first flange portion 56 b is in contact with the upper support block 52. Then, the suction member 59 generates a suction force by an electromagnetic force generated by passing a current through the coil 60, the second flange portion 56d is sucked by this suction force, and the drive valve 56 is resisted against the biasing force of the return spring 57. And can move downward.

Furthermore, since the drive valve 56 and the external piston 58 are fitted and supported in the housing 51 so as to be movable, the axial direction of the external piston 58 is determined by the housing 51, the upper support block 52, the drive valve 56, and the external piston 58. A first pressure chamber R ₁₁ and a second pressure chamber R ₁₂ are defined in one and the other. In this case, the first pressure chamber R ₁₁ is defined by the upper support block 52, the drive valve 56, and the external piston 58, and the second pressure chamber R ₁₂ is defined by the upper support block 52 and the external piston 58. On the other hand, the drive valve 56 has a communication hole 61 formed in the center thereof so as to penetrate in the axial direction. The communication hole 61 has an upper end communicating with the first pressure chamber R ₁₁ . Further, the drive valve 56 is formed with a plurality of connection ports 61a along the radial direction at a substantially intermediate position in the axial direction, and is positioned outside the connection port 61a and on the outer peripheral surface of the drive valve 56. An annular connecting groove 61b is formed. The communication hole 61, the connection port 61a, and the connection groove 61b are in communication with each other.

In the housing 51, a high pressure port P ₁ that communicates the outside with the support hole 55 is formed, and a decompression port P ₂ that communicates the exterior and the decompression chamber R ₁₃ that houses the return spring 57 is formed. The high pressure port P ₁ and the pressure reducing port P ₂ can communicate with the communication hole 61 via the connection groove 61 b and the connection port 61 a at different movement positions of the drive valve 56. The housing 51 and the upper support block 52 form a control pressure port P ₃ that communicates with the outside through the support hole 52a. This control pressure port P ₃ communicates with the first pressure chamber R ₁₁ . The high pressure port P ₁ is connected to the accumulator 42 (see FIG. 1) via the high pressure supply pipe 43, and the pressure reduction port P ₂ is connected to the third hydraulic pipe 32 via the pressure reduction supply pipe 47 to control pressure. The port P ₃ is connected to the second hydraulic pipe 28 via the control pressure supply pipe 45. The decompression port P ₂ communicates with an annular groove 58a formed in the outer peripheral portion of the external piston 58 via the decompression chamber R ₁₃ and the connection port P ₂₁ .

In this case, the relationship between the pressure receiving area a _{1 of the} hydraulic pressure received by the first support portion 56 a of the drive valve 56 from the first pressure chamber R ₁₁ and the pressure receiving area a _{2 of the} hydraulic pressure received by the second support portion 56 c of the drive piston 13 is , so that the a _1> a _2, the support portions 56a of the drive valve 56, the outer diameter of 56c are set. Therefore, the electromagnetic force applied by the coil 60 when the drive valve 56 moves downward, that is, the current value to the coil 60 is the drive force corresponding to the pressure receiving area difference a ₁ -a ₂ before and after the drive valve 56. And the resultant force with the urging force of the return spring 57 and the driving force corresponding to various sliding resistances can be secured. By setting the pressure receiving area difference a ₁ -a ₂ small, the power consumption can be reduced. Can be reduced.

Further, in the housing 51 and the upper support block 52, the external pressure port P ₄ for communicating the outside and the support hole 52a is formed located above the control pressure port P ₃ as described above. One end of the external pressure port P ₄ communicates with the second pressure chamber R ₁₂ , and the other end is connected to the first hydraulic pipe 24 via the external pressure supply pipe 46.

In this case, the control pressure acting on the first pressure chamber R ₁₁ acts as an upward force on the external piston 58, while the external pressure acting on the second pressure chamber R ₁₂ acts on the external piston 58 as a downward force. Acts as Then, the external piston 58 which fits movably to the supporting hole 52a of the upper support block 52, a pressure receiving area of the hydraulic pressure applied from the first pressure chamber R _11, pressure receiving area of the hydraulic pressure acting from the second pressure chamber R ₁₂ Are equal, that is, “control pressure × pressure receiving area of the external piston 58 = external pressure × pressure receiving area of the external piston 58”, and the external piston 58 is in a floating state and is prevented from being fixed to the upper support block 52.

Therefore, when the coil 60 is not energized, the drive valve 56 is positioned at a position in contact with the upper support block 52 by the urging force of the return spring 57, and the communication hole 61 of the drive valve 56 is in the first pressure chamber R. while communicating with the _11, by connecting the port 61a and the coupling groove 61b is communicated with the vacuum port P ₂ through the decompression chamber R _13, the control pressure port P ₃ and decompression port P ₂ are communicated with each other by communicating hole 61 .

On the other hand, when the coil 60 is energized, the drive valve 56 moves downward against the urging force of the return spring 57 by the attractive force. Then, the connection port 61a and the connection groove 61b communicate with the high pressure port P ₁ while the communication hole 61 of the drive valve 56 communicates with the first pressure chamber R ₁₁ , so that the high pressure port P ₁ and the control pressure port P ₃ are connected. The communication is made through the communication hole 61.

  A seal member 62 is interposed between the housing 51 and the upper support block 52, and a seal member 63 is interposed between the housing 51 and the lower support block 53. Seal members 64 and 65 are interposed between the valve 56 and a seal member 66 is interposed between the upper support block 52 and the external piston 58, so that sealing performance is ensured. Further, the housing 51 is supported by a casing (not shown) of the ABS 22, and a sealing member 67 is interposed between the housing 51 and the casing, so that sealing performance is ensured.

As described above, in the pressure control valve 44 in the vehicle braking device of the present embodiment, when the coil 60 is in the demagnetized state, the drive valve 56 is in a position in contact with the upper support block 52 by the return spring 57. while communicating hole 61 communicating with the first pressure chamber R _11, connection port 61a and the coupling groove 61b is in communication with the vacuum port P _2. Therefore, the control pressure port P ₃ and the pressure reduction port P ₂ are in communication with each other by the first pressure chamber R ₁₁ and the communication hole 61, while the high pressure port P ₁ and the control pressure port P ₃ are in a disconnected state.

When the coil 60 is energized from this state, the drive valve 56 moves downward against the urging force of the return spring 57 by the generated suction force. At this time, the control pressure acting on the external piston 58 from the first pressure chamber R ₁₁ is equal to the external pressure acting on the second pressure chamber R ₁₂ , so that the drive valve 56 is moved downward. The control pressure and the external pressure do not adversely affect the driving force, and the driving valve 56 can be properly moved downward. Then, the drive valve 56 when moved downward, while communicating hole 61 of the drive valve 56 is communicated with the first pressure chamber R _11, connection port 61a and the coupling groove 61b communicates switched to the high-pressure port P _1. Therefore, the high pressure port P ₁ and the control pressure port P ₃ communicate with each other through the first pressure chamber R ₁₁ and the communication hole 61, while the pressure reduction port P ₂ and the control pressure port P ₃ are blocked.

Accordingly, the pressure acting from the high pressure supply pipe 43 through the high pressure port P ₁ , that is, high pressure hydraulic oil flows from the connection groove 61 b through the connection port 61 a into the communication hole 61, and from the communication hole 61 to the first pressure chamber R. flow _11, so that the ejected as control pressure to the control pressure supply pipe 45 from the control pressure port P _3. In this case, the control pressure discharged to the control pressure supply pipe 45 can be adjusted by controlling the movement amount of the drive valve 56 by the current value to the coil 60.

In this state, when the value of the current supplied to the coil 60 is decreased, the generated suction force is reduced and the drive valve 56 is moved upward by the urging force of the return spring 57. Then, while communicating hole 61 of the drive valve 56 is communicated with the first pressure chamber R _11, connection port 61a and the coupling groove 61b communicates switched to vacuum port P _2. Therefore, the decompression port P ₂ and the control pressure port P ₃ communicate with each other through the first pressure chamber R ₁₁ and the communication hole 61, while the high pressure port P ₁ and the control pressure port P ₃ are blocked.

Accordingly, the control pressure discharged from the first pressure chamber R ₁₁ to the control pressure supply pipe 45 through the control pressure port P ₃ , that is, the hydraulic oil is returned from the first pressure chamber R ₁₁ to the communication hole 61, and the connection port 61 a and through the coupling groove 61b flows into the decompression chamber R _13, it is discharged to the reduced-pressure delivery pipe 47 from the vacuum port P _2.

Further, the coil 60 is demagnetized, and the control pressure port P ₃ and the pressure reduction port P ₂ are in communication with each other by the first pressure chamber R ₁₁ and the communication hole 61, while the high pressure port P ₁ and the control pressure port P ₃ are in a disconnected state. In this state, when external pressure, that is, hydraulic fluid is supplied from the external pressure supply pipe 46 to the second pressure chamber R ₁₂ via the external pressure port P ₄ , the external piston 58 moves downward. The external piston 58 pushes the drive valve 56 downward to move it. Then, the drive valve 56 is moved downward against the biasing force of the return spring 57, in the same manner as described above, while communicating hole 61 of the drive valve 56 is communicated with the first pressure chamber R _11, connecting ports 61a and coupling groove 61b is communicated with the high pressure port P _1.

Accordingly, the high pressure port P ₁ and the control pressure port P ₃ communicate with each other by the first pressure chamber R ₁₁ and the communication hole 61, while the pressure reduction port P ₂ and the control pressure port P ₃ are blocked. high pressure hydraulic fluid is supplied from the high-pressure supply pipe 43 through the high-pressure port P _1, flows into the communication hole 61 through the connection port 61a from the coupling groove 61b, flows from the communication hole 61 into the first pressure chamber R _11, the control pressure port P ₃ is discharged to the control pressure supply pipe 45 as a control pressure. In this case, the control pressure discharged to the control pressure supply pipe 45 can be adjusted by controlling the external pressure acting on the second pressure chamber R ₁₂ from the external pressure supply pipe 46 via the external pressure port P _4. .

Further, in the vehicle braking apparatus of the present embodiment, as shown in FIG. 1, a hydraulic discharge pipe (discharge) that can discharge the hydraulic pressure of the front pressure chamber R ₁ to the reservoir tank 33 when the drive piston 13 is in the initial position. Line) 81 and a shutoff valve 82 that is closed by an operating force input from the brake pedal 15 to the drive piston 13 is provided in the hydraulic pressure discharge pipe 81. In this embodiment, the shutoff valve 82 is configured to be closed by the hydraulic pressure acting on the rear pressure chamber R ₂ by the pressure control valve 44.

  That is, in the shut-off valve 82, a housing 83 having a hollow shape is formed with a connection port 83a, a discharge port 83b, and an operation port 83c. A movable element 84 is movably supported in the housing 83. The movable element 84 is formed with a communication hole 85 that allows the connection port 83a and the discharge port 83b to communicate with each other. A ball valve 86 is attached to face one end of the ball. The movable element 84 is urged and supported in a direction in which one end portion of the communication hole 85 is separated from the ball valve 86 by the urging force of the urging spring 87 interposed between the movable element 84 and the housing 83. When the movable element 84 moves against the urging force of the urging spring 87, one end portion of the communication hole 85 comes into close contact with the ball valve 86, and the communication hole 85 can be closed.

In the master cylinder 11, return ports 88 a and 88 b communicating with the front pressure chamber R ₁ are formed through the cylinder 12 and the large-diameter piston 13 c of the drive piston 13, and the cylinder 12 has a rear pressure chamber R _2. An operating port 89 that communicates with is formed through. The connection port 83a of the shutoff valve 82 is connected to the return port 88a via the connection pipe 81a of the hydraulic discharge pipe 81, and the discharge port 83b is connected to the reservoir tank 33 via the discharge pipe 81b. The operation port 83 c of the shut-off valve 82 is connected to the operation port 89 via the hydraulic operation pipe 90. In addition, between the cylinder 12 and the drive piston 13, a one-way seal 91 is attached to the main part thereof to prevent hydraulic pressure leakage.

Accordingly, when the drive piston 13 is in the initial position, the movable element 84 of the shut-off valve 82 opens the communication hole 85 with one end portion of the communication hole 85 being separated from the ball valve 86 by the biasing force of the biasing spring 87. Yes. Therefore, the front pressure chamber R ₁ in the master cylinder 11 is communicated with the reservoir tank 33 through the return port 88a, 88b, connecting pipe 81a, connecting ports 83a, communication holes 85, the discharge port 83 b, the exhaust pipe 81b. From this condition, the driving piston 13 moves forward, the hydraulic pressure from the second hydraulic pipe 28 acts on the rear pressure chamber R _2, the rear pressure chamber R ₂ of the hydraulic actuation port 89, hydraulic piping 90, the operating ports 83c It acts on the mover 84 via. Then, the mover 84 moves against the urging force of the urging spring 87, and one end portion of the communication hole 85 comes into contact with the ball valve 86 to close the communication hole 85. Therefore, the communication between the front pressure chamber R ₁ of the master cylinder 11 and the reservoir tank 33 can be blocked.

In the vehicle braking apparatus of the present embodiment configured as described above, the electronic control unit (ECU) 71 generates a target control pressure corresponding to the operation force (pedal depression force) input from the brake pedal 15 to the drive piston 13. By setting (control pressure setting means) and applying the set target control pressure to the rear pressure chamber R ₂ to assist the drive piston 13, an appropriate control pressure is output from the front pressure chamber R ₁ , and the ABS 22 The wheel cylinders 21FR, 21FL, 21RR, 21RL are actuated by applying braking hydraulic pressure to the front cylinders FR, FL and the rear wheels RR, RL.

That is, the brake pedal 15 is provided with a stroke sensor 72 that detects the pedal stroke Sp of the brake pedal 15 and a pedal force sensor 73 that detects the pedal depression force Fp, and outputs each detection result to the ECU 71. . The first and second hydraulic pipes 24 and 28 are provided with a first pressure sensor 74 and a second pressure sensor 75 for detecting the hydraulic pressure. The first pressure sensor 74, and outputs through the first hydraulic pipe 24 from the front pressure chamber R ₁ the front wheels FR, FL of the wheel cylinders 21FR, detects the control pressure P _M supplied to 21FL, the detection result to the ECU71 . On the other hand, the second pressure sensor 75 outputs the rear wheels RR from the rear pressure chamber R ₂ through the second hydraulic pipe 28, RL of the wheel cylinders 21RR, detects the control pressure P _A to be supplied to 21RL, the detection result to the ECU71 is doing.

Furthermore, a pressure sensor 76 for detecting the oil pressure is provided in the high-pressure supply pipe 43 extending from the accumulator 42 to the pressure control valve 44. The pressure sensor 76 detects the hydraulic pressure P _H through the high-pressure supply pipe 43 extending from the accumulator 42 to the pressure control valve 44, and outputs the detection result to the ECU 71. The front wheels FR and FL and the rear wheels RR and RL are respectively provided with wheel speed sensors 77 and output the detected wheel speeds to the ECU 71.

Accordingly, ECU 71 can pedal effort Fp of the brake pedal 15 the pedal pressure sensor 73 has detected (or the pedal stroke Sp of the stroke sensor 72 detects) sets the target control pressure P _MT based on, driven valve in the pressure control valve 44 On the other hand, the control pressure P _M detected by the first pressure sensor 74 is fed back to control the target control pressure P _MT and the control pressure P _M so as to coincide with each other. In this case, ECU 71 has a map indicating the target control pressure P _MT for the pedal depressing force Fp, and controls the pressure control valve 44 based on this map.

The servo ratio of the master cylinder 11, the diameter of the small-diameter piston 13b A _A, when the diameter of the large-diameter piston 13c and A _M, is set by the _{A M} / A A. Then, the control pressure P _M discharged from the front pressure chamber R ₁ of the master cylinder 11 to the first hydraulic pipe 24 and applied to the wheel cylinders 21 FR and 21 FL of the front wheels FR and FL, and the rear pressure chamber R ₂ of the master cylinder 11. from discharged into the second hydraulic pipe 28, when the rear wheels RR, RL of the wheel cylinders 21RR, and a control pressure P _a applied to 21RL and the pressure represents the target control pressure P _MT with respect to the pedal effort Fp The slope may be set to Rp / A _A on the map. Here, Rp is the lever ratio of the brake pedal 15 and is L ₂ / L ₁ .

The braking force control by the vehicle braking device of the present embodiment will be described in detail. As shown in FIGS. 1 and 2, when the occupant steps on the brake pedal 15, the driving piston 13 moves forward by the operating force (see FIG. 1) Move to the left. At this time, the depression sensor 73 detects the pedal effort Fp, ECU 71 sets the target control pressure P _MT based on the pedal effort Fp. Then, ECU 71, this on the basis of the target control pressure P _MT to control the pressure control valve 44, to apply a predetermined control pressure P _A in the rear pressure chamber R _2. The ECU 71 feeds back the control pressure P _M detected by the first pressure sensor 74 and controls the target control pressure P _MT and the control pressure P _M to coincide with each other.

That is, the coil 60 is energized by the pressure control valve 44, and the drive valve 56 is moved downward against the urging force of the return spring 57 by the generated suction force. Then, the communication hole 61 communicates with the high pressure port P ₁ through the connection port 61a and the connection groove 61b, and the high pressure port P ₁ communicates with the control pressure port P ₃ through the communication hole 61 and the first pressure chamber R _11. On the other hand, the pressure reducing port P ₂ and the control pressure port P ₃ are blocked. Therefore, the hydraulic pressure of the accumulator 42 is supplied from the high pressure supply pipe 43 to the high pressure port P ₁ , supplied to the first pressure chamber R ₁₁ through the communication hole 61, and second from the control pressure port P ₃ through the control pressure supply pipe 45. It is supplied to the hydraulic pipe 28. Then, the hydraulic pressure supplied to the second hydraulic pipe 28 acts on the rear pressure chamber R ₂ and assists the drive piston 13, so that an appropriate control hydraulic pressure P is applied from the front pressure chamber R ₁ to the first hydraulic pipe 24. _M is discharged.

Accordingly, the control pressure P _M is applied from the first hydraulic pipe 24 to the wheel cylinders 21FR and 21FL of the front wheels FR and FL, and the control pressure P _M is applied from the second hydraulic pipe 28 to the wheel cylinders 21RR and 21RL of the rear wheels RR and RL. _A will be given, and the braking force according to the operating force of the brake pedal 15 of a passenger | crew can be generated with respect to front wheel FR, FL and rear wheel RR, RL.

In this case, the occupant performs the operation of depressing and returning the brake pedal 15 as necessary, so that the drive piston 13 reciprocates back and forth in accordance with the operation of the brake pedal 15 by the occupant and returns to the initial position. May return. However, in the present embodiment, a hydraulic discharge pipe 81 that communicates the front pressure chamber R ₁ and the reservoir tank 33 is provided, and the hydraulic discharge pipe 81 is closed by an operating force input from the brake pedal 15 to the drive piston 13. A shut-off valve 82 is provided.

Therefore, in a state where the occupant applies operating force to the drive piston 13 by the brake pedal 15, the hydraulic pressure adjusted by the pressure control valve 44 acts on the rear pressure chamber R ₂ via the second hydraulic pipe 28. The hydraulic pressure in the rear pressure chamber R ₂ acts on the mover 84 of the shut-off valve 82 to close the hydraulic pressure discharge pipe 81. Therefore, when the occupant is operating the brake, the front pressure chamber R ₁ of the master cylinder 11 is disconnected from the reservoir tank 33, and even if the drive piston 13 temporarily returns to the initial position, the front pressure chamber R ₁ The hydraulic pressure in the chamber R ₁ is not discharged to the reservoir tank 33, and hunting of the drive piston 13 is suppressed.

On the other hand, when a failure occurs in the power system, the braking hydraulic pressure applied to each wheel cylinder 21FR, 21FL, 21RR, 21RL is controlled by controlling the current value to the coil 60 of the pressure control valve 44. The oil pressure cannot be controlled properly. However, in this embodiment, the pressure control valve 44 is provided with an external piston 58 that is operated by pressure (external pressure) generated in the front pressure chamber R ₁ of the master cylinder 11, and the drive valve 56 is controlled by the external piston 58. Therefore, an appropriate control pressure can be output.

When the occupant steps on the brake pedal 15 at the time of failure of the power supply system, the driving piston 13 moves forward by the operating force, and the front pressure chamber R ₁ is pressurized by the advancement of the driving piston 13. The hydraulic pressure in the chamber R ₁ is discharged as an external pressure to the first hydraulic pipe 24 and acts on the pressure control valve 44 through the external pressure supply pipe 46.

At this pressure control valve 44, an external pressure acts on the second pressure chamber R ₁₂ via the external pressure port P ₄ from the external pressure supply pipe 46, the drive valve 56 by the external piston 58 is moved downward downward Press to move. Then, the communication hole 61 communicates with the high pressure port P ₁ through the connection port 61a and the connection groove 61b, and the high pressure port P ₁ communicates with the control pressure port P ₃ through the communication hole 61 and the first pressure chamber R _11. On the other hand, the pressure reducing port P ₂ and the control pressure port P ₃ are blocked. Therefore, the hydraulic pressure of the accumulator 42 is supplied from the high pressure supply pipe 43 to the high pressure port P ₁ , supplied to the first pressure chamber R ₁₁ through the communication hole 61, and second from the control pressure port P ₃ through the control pressure supply pipe 45. It is supplied to the hydraulic pipe 28. Then, the hydraulic pressure supplied to the second hydraulic pipe 28 acts on the rear pressure chamber R ₂ to assist the drive piston 13, so that an appropriate control pressure P is applied from the front pressure chamber R ₁ to the first hydraulic pipe 24. _M is discharged.

Therefore, even if the power supply system fails, the control pressure P _M is applied from the first hydraulic pipe 24 to the wheel cylinders 21FR, 21FL of the front wheels FR, FL, and the rear hydraulic valves RL, RL of the rear wheels RR, RL are applied. wheel cylinders 21RR, becomes the control pressure P _a to 21RL are applied, can generate a braking force corresponding to the operation force exerted on the brake pedal 15 relative to the front wheels FR, FL and rear wheels RR, RL.

As described above, in the vehicle brake device of the first embodiment, the drive piston 13 is movably supported in the cylinder 12 to partition the front pressure chamber R ₁ and the rear pressure chamber R ₂ , and the brake pedal 15. Is provided with a master cylinder 11 capable of outputting the hydraulic pressure of the front pressure chamber R ₁ by moving the drive piston 13. The wheel cylinders 21 FR and 21 FL are connected to the front pressure chamber R ₁ and electromagnetic force based on the target control pressure is provided. the control pressure of the hydraulic regulating pressure from accumulator 42 by moving rear pressure chamber R ₂ and the wheel cylinders 21RR, as well as a possible output 21RL driven valve 56, the movement outside pressure from the front pressure chamber R ₁ rear pressure chamber R ₂ hydraulic temper pressure control pressure from the accumulator 42 by moving the drive valve 56 by the external piston 58 and Hoirushi Sunda 21RR, is provided with a pressure control valve 44 can be output to 21RL.

Therefore, when the normal power supply system, ECU 71 sets the target control pressure P _MT corresponding to the pedal depressing force Fp, by controlling the pressure control valve 44 on the basis of the target control pressure P _MT, pressure control from the accumulator 42 An appropriate hydraulic pressure is supplied to the rear pressure chamber R ₂ by the valve 44 to assist the drive piston 13, and an appropriate control pressure can be supplied to each of the hydraulic pipes 24 and 28, and this control oil is supplied via the ABS 22. Thus, an appropriate braking force corresponding to the operating force of the occupant's brake pedal 15 can be generated on the front wheels FR, FL and the rear wheels RR, RL by acting on the wheel cylinders 21FR, 21FL, 21RR, 21RL.

On the other hand, when the power supply system fails, the drive piston 13 moves in accordance with the operation of the brake pedal 15 to pressurize the front pressure chamber R ₁ , and the hydraulic pressure in the front pressure chamber R ₁ is supplied to the pressure control valve 44 as an external pressure. By acting, an appropriate hydraulic pressure is supplied from the accumulator 42 to the rear pressure chamber R ₂ by the pressure control valve 44 to assist the drive piston 13, and an appropriate control pressure is supplied to the hydraulic pipes 24 and 28. The control oil is allowed to act on the wheel cylinders 21FR, 21FL, 21RR, 21RL via the ABS 22, and is appropriate for the front wheel FR, FL and the rear wheels RR, RL according to the operating force of the brake pedal 15 of the occupant. Can generate a large braking force.

  As described above, in this embodiment, by applying the pressure control valve 44 that is operated by the electromagnetic force and the external pressure, the control pressure according to the operation of the brake pedal 15 by the occupant is surely generated regardless of the state of the power supply system. As a result, the hydraulic path can be simplified to simplify the structure, and the manufacturing cost can be reduced. On the other hand, appropriate braking force control can be achieved, and reliability and Safety can be improved.

Further, in the vehicle braking device of the first embodiment, a hydraulic pressure discharge pipe 81 that can discharge the hydraulic pressure of the front pressure chamber R ₁ to the reservoir tank 33 when the drive piston 13 is in the initial position is provided. In addition, a shut-off valve 82 that is closed by an operating force input from the brake pedal 15 to the drive piston 13 is provided. Therefore, in a state where the occupant applies operating force to the drive piston 13 by the brake pedal 15, the shut-off valve 82 closes the hydraulic pressure discharge pipe 81 by this operation force, and the drive piston 13 temporarily moves to the initial position. even back, never hydraulic pressure in the front pressure chamber R ₁ is discharged into the reservoir tank 33, is possible to improve the drivability by improving the operability of the braking operation by hunting of the drive piston 13 is suppressed In addition, an appropriate braking force can be ensured and highly accurate braking force control can be performed.

In this case, the shutoff valve 82 is closed by the hydraulic pressure acting on the rear pressure chamber R ₂ by the pressure control valve 44. Accordingly, in a state in which the occupant is applied an operating force to the drive piston 13 by the brake pedal 15, the hydraulic pressure regulated by the pressure control valve 44 acts on the rear pressure chamber R ₂ through the second hydraulic pipe 28, The hydraulic pressure in the rear pressure chamber R ₂ acts on the mover 84 of the shut-off valve 82 to close the hydraulic pressure discharge pipe 81, and hunting of the drive piston 13 can be suppressed with a simple configuration.

  FIG. 3 is a schematic configuration diagram illustrating a vehicular braking apparatus according to a second embodiment of the present invention, and FIG. 4 is a cross-sectional view of a pressure control valve in the vehicular braking apparatus according to the second embodiment. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  In the vehicular braking apparatus according to the second embodiment, as shown in FIG. 3, the master cylinder 111 is configured such that an input piston 113 and a pressurizing piston 114 as drive pistons are supported in a cylinder 112 so as to be movable in the axial direction. ing. The input piston 113 arranged on the base end side of the cylinder 112 is connected to the operation rod 20 of the brake pedal 15 at the base end portion, and can be moved via the operation rod 20 by the operation of the brake pedal 15 by the occupant. It has become. Further, the input piston 113 has an outer peripheral surface fitted to the first inner peripheral surface 112a of the cylinder 112 and supported so as to be movable along the axial direction, and the outer peripheral surface of the flange portion 113a is the first inner peripheral surface of the cylinder 112. It fits in the 2nd internal peripheral surface 112b larger diameter than 112a, and is supported so that a movement along an axial direction is possible. The flange portion 113a abuts on the step portion 112c between the first inner peripheral surface 112a and the second inner peripheral surface 112b, so that the forward movement stroke is restricted, and the flange portion 113a contacts the support member 115. By contacting, the moving stroke on the reverse side is regulated. The input piston 113 is urged and supported at a position where the flange portion 113 a abuts against the support member 115 by a reaction force spring 117 interposed between the support member 115 and the bracket 116.

  The pressurizing piston 114 is disposed on the tip side of the input piston 113 in the cylinder 112, and the outer peripheral surface is movably supported by the first inner peripheral surface 112 a of the cylinder 112, and the outer peripheral surface of the flange portion 114 a is the cylinder 112. The third inner peripheral surface 112d is movably supported. Then, the movement stroke of the pressurizing piston 114 is restricted by the flange portion 114a coming into contact with the lid member 118 or the stepped portion 112e. The pressurizing piston 114 is urged and supported at a position where the flange portion 114a abuts on the stepped portion 112e by the urging force of the urging spring 120 interposed between the pressing piston 114 and the support plate 119.

Further, as described above, the input piston 113 and the pressurizing piston 114 are coaxially disposed in the cylinder 112 so as to be relatively movable, so that the front pressure chamber R ₁ , the rear pressure chamber R _2, and the circulation pressure chamber are arranged. R ₃ and reaction force chamber R ₄ are partitioned. The rear pressure chamber R ₂ and the circulation pressure chamber R ₃ are communicated by a communication passage 121 formed in the input piston 113, and when the input piston 113 approaches the pressurizing piston 114, this seal member ( A closing member 122 is attached to the rear end surface of the pressure piston 114.

On the other hand, the front wheels FR, FL and the rear wheels RR, RL are provided with wheel cylinders 21FR, 21FL, 21RR, 21RL, which can be operated by the ABS 22. That is, the first and the first hydraulic pipe 124 is connected to a pressure port 123 communicating with the front pressure chamber R ₁ in the master cylinder 111, the first hydraulic pipe 124 is oil pressure supply line 25a, the wheel cylinders 21FR through 25b , 21FL. The second pressure port 125 communicating with the circular pressure chamber R ₃ of the master cylinder 111, a second hydraulic pipe 126 is connected, the second hydraulic pipe 126 is oil pressure supply line 29a, through the 29b wheel The cylinders 21RR and 21RL are connected to each other.

  Further, hydraulic discharge pipes 30a and 30b are connected to the respective hydraulic supply pipes 25a and 25b, and hydraulic discharge pipes 31a and 31b are connected to the respective hydraulic supply pipes 29a and 29b, and the respective hydraulic discharge pipes 30a, 30b, 31a and 31b have their front ends assembled together and connected to the third hydraulic pipe 32. This third hydraulic pipe 32 is connected to the fourth pressure port 127 of the master cylinder 111, and is supplied and discharged from the fifth pressure port 128. It is connected to the reservoir tank 33 via a pipe 129.

  The pressure increasing valves 34a, 34b, 35a, 35b are arranged in the hydraulic pressure supply pipes 25a, 25b, 29a, 29b, and the pressure reducing valves 36a, 36b, 37a, 37b are arranged in the hydraulic pressure discharge pipes 30a, 30b, 31a, 31b. Has been.

The hydraulic pump 38 can be driven by a motor 39 and is connected to the reservoir tank 33 through a pipe 40 and is connected to an accumulator 42 through a pipe 41. The hydraulic pump 38 and the accumulator 42 are connected to a pressure control valve 131 via a high pressure supply pipe 130. The pressure control valve 131 is actuated by electromagnetic force to regulate the hydraulic pressure accumulated in the accumulator 42 and output it to the rear pressure chamber R ₂ of the master cylinder 111 and the wheel cylinders 21 RR and 21 RL of the ABS 22. The pressure piston 114 can be advanced by the hydraulic pressure to R _2, and the hydraulic pressure from the front pressure chamber R ₁ of the master cylinder 111 can be output to the wheel cylinders 21 FR and 21 FL of the ABS 22.

  That is, in this pressure control valve 131, as shown in FIG. 4, the housing 151 has a cylindrical shape, and a plurality of step portions are formed along the axial direction in the through-hole 152 formed inside. Three support holes 153a, 153b, and 153c having a large diameter downward are formed. A drive valve 154 is supported in the through-hole 152 so as to be movable up and down. The drive valve 154 is supported by the support holes 153a, 153b, and 153c. 154c and a large diameter portion 154d. The drive valve 154 is urged and supported upward by the return spring 155, so that the large-diameter portion 154d is urged and supported at a position where the large-diameter portion 154d contacts the stepped portion 152a, while the solenoid 156 is energized. It can be moved downward by the generated electromagnetic force.

The housing 151 is formed with a high pressure port P ₁ , a pressure reduction port P _2, and a control pressure port P ₃ . On the other hand, the drive valve 154 is formed with a communication passage 157 where the first through hole 157a along the axial direction intersects with the second through hole 157b along the radial direction.

  A support hole 153d having a smaller diameter than the support hole 153a is formed in the upper portion of the through hole 152 of the housing 151. An external piston 158 is supported in the through hole 513 in series above the drive valve 154 so as to be movable up and down. The external piston 158 is supported in a movable manner in the support holes 153a and 153d. The support portions 158a and 158b are provided.

The drive valve 154 and the external piston 158 are movably supported in the housing 151, so that the first pressure chamber R is positioned in front of the external piston 158 by the housing 151, the drive valve 154, and the external piston 158. ₁₁ is formed, and the second pressure chamber R ₁₂ is defined by the housing 151 and the external piston 158 on the rear side of the external piston 158. The housing 151 is formed with an external pressure port P ₄ and an adjustment pressure port P ₅ . Note that the control pressure port P ₃ communicates with the first pressure chamber R ₁₁ between the drive valve 154 and the external piston 158. Further, the decompression port P ₂ and the adjustment pressure port P ₅ communicate with each other.

In this case, the external piston 158 has a stepped portion, and the pressure receiving area a _{11 of} the first pressure chamber R ₁₁ partitioned from the drive valve 154 on the front side is equal to the front pressure chamber on the rear side of the external piston 158. hydraulic from R ₁ is set larger than the pressure receiving area a ₁₂ second pressure chamber R ₁₂ acting. That is, the relationship between the pressure receiving area a _{11 of the} hydraulic pressure received by the external piston 158 from the first pressure chamber R ₁₁ and the pressure receiving area a _{12 of the} hydraulic pressure received by the external piston 158 from the front pressure chamber R ₁ is a ₁₁ > a ₁₂ . Thus, the outer diameter of the external piston 158 is set.

Therefore, when not energized solenoid 156, drive valve 154 is positioned upward by the urging force of the return spring 155, under reduced pressure and the control pressure port P ₃ and the first pressure chamber R ₁₁ by communicating path 157 port P ₂ Are communicated, and the high-pressure port P ₁ is shut off. On the other hand, when the solenoid 156 is energized, the drive valve 154 moves downward against the urging force of the return spring 155 by electromagnetic force. Then, the high pressure port P ₁ , the first pressure chamber R ₁₁ and the control pressure port P ₃ are communicated with each other by the communication path 157, and the pressure reduction port P ₂ is shut off. Further, when an external pressure is applied to the external pressure port P ₄ , the external piston 158 moves downward, and the drive valve 154 moves downward against the urging force of the return spring 155. The high pressure port P ₁ , the first pressure chamber R _11, and the control pressure port P ₃ communicate with each other through the passage 157.

A high pressure supply pipe 130 from the hydraulic pump 38 and the accumulator 42 is connected to the high pressure port P ₁ of the pressure control valve 131. The pressure control valve 131 has a control pressure port P ₃ connected to the second hydraulic pipe 126 via a control pressure supply pipe 132.

In addition, one end of the fourth hydraulic pipe 134 is connected to the third pressure port 133 communicating with the reaction force chamber R ₄ of the master cylinder 111, and the other end is connected to the third hydraulic pipe 32, and the pressure The pressure reducing port P ₂ of the control valve 131 is connected. The fourth hydraulic pipe 134 is provided with a reaction force control valve 135. The reaction force control valve 135 is a normally open type on-off valve that is closed when power is supplied. The fourth hydraulic pipe 134 is provided with a stroke simulator 136.

Further, a connection pipe 137 is installed between the high pressure port P ₁ of the pressure control valve 131 and the first hydraulic pipe 124, and a communication valve 138 is attached to the connection pipe 137. The communication valve 138 is a normally closed type on-off valve that opens when power is supplied. One end of the external pressure supply pipe 139 is connected to the external pressure port P ₄ of the pressure control valve 131, and the other end is connected to the first hydraulic pipe 124. Therefore, the external piston 158 can be moved downward by the hydraulic pressure in the front pressure chamber R ₁ acting as an external pressure on the external pressure port P ₄ through the first hydraulic pipe 124 and the external pressure supply pipe 139.

Further, in the vehicle braking apparatus of the present embodiment, as shown in FIG. 3, as shown in FIG. 3, a hydraulic pressure discharge pipe that can discharge the hydraulic pressure in the front pressure chamber R ₁ to the reservoir tank 33 when the pressurizing piston 114 is in the initial position. A discharge line 141 is provided, and a shut-off valve 142 that is closed by an operation force input from the brake pedal 15 to the input piston 113 is provided in the hydraulic pressure discharge pipe 141. In this embodiment, the shut-off valve 142 is configured so as to close the hydraulic pressure acting on the reaction force chamber R _4.

  The shut-off valve 142 has the same configuration as the shut-off valve 82 of the first embodiment described above. A connection port 83a, a discharge port 83b, and an operation port 83c are formed in the housing 83, and the movable element 84 is movable inside. A communication hole 85 is formed in the movable element 84, and a ball valve 86 is mounted facing one end of the communication hole 85. The movable element 84 is biased and supported in a direction in which one end portion of the communication hole 85 is separated from the ball valve 86 by the biasing force of the biasing spring 87, and the movable element 84 resists the biasing force of the biasing spring 87. By moving, one end of the communication hole 85 can be brought into close contact with the ball valve 86 and the communication hole 85 can be closed.

At the master cylinder 111, the cylinder 112 and the pressure piston 114, ports 143a return to communicate with the front pressure chamber R _1, 143b is formed through, the cylinder 112 is communicated to the counterforce chamber R ₄ operation A port 144 is formed to penetrate therethrough. The connection port 83a of the shutoff valve 142 is connected to the return port 143a via the connection pipe 81a of the hydraulic pressure discharge pipe 141, and the discharge port 83b is connected to the reservoir tank 33 via the discharge pipe 81b. The operation port 83 c of the shut-off valve 142 is connected to the operation port 144 via the hydraulic operation pipe 145.

Therefore, when the pressurizing piston 114 is in the initial position, the movable element 84 of the shut-off valve 142 opens the communication hole 85 by separating one end of the communication hole 85 from the ball valve 86 by the biasing force of the biasing spring 87. ing. Therefore, the front pressure chamber R ₁ in the master cylinder 111 is communicated with the reservoir tank 33 through the return port 143a, 143b, connection pipe 81a, connecting ports 83a, communication holes 85, the discharge port 83 b, the exhaust pipe 81b. From this state, the input piston 113 moves forward, the counterforce chamber R ₄ is pressurized, the hydraulic actuation port 144 of the reaction force chamber R _4, hydraulic piping 145, the mover 84 through the operating ports 83c Works. Then, the mover 84 moves against the urging force of the urging spring 87, and one end portion of the communication hole 85 comes into contact with the ball valve 86 to close the communication hole 85. Therefore, the communication between the front pressure chamber R ₁ of the master cylinder 111 and the reservoir tank 33 can be blocked.

The ECU 71 sets a target control pressure (control pressure setting means) corresponding to the operating force (pedal stroke or pedaling force) input from the brake pedal 15 to the input piston 113, and the set target control is performed by the pressure control valve 131. wheel cylinders 21RR of the rear wheel side pressure, causes output to 21RL, assists pressure piston 114 is caused to act on the rear pressure chamber R _2, is output from the front pressure chamber R ₁ of the front-wheel wheel cylinder 21FR, the 21FL The Therefore, the brake cylinders 21FR, 21FL, 21RR, and 21RL are actuated with appropriate braking hydraulic pressures via the ABS 22 to operate the front wheels FR and FL and the rear wheels RR and RL.

That is, the brake pedal 15 is provided with a stroke sensor 72 that detects the pedal stroke Sp and a pedaling force sensor 73 that detects the pedaling force Fp, and outputs each detection result to the ECU 71. The first hydraulic pipe 124 is provided with a first pressure sensor 74 that detects a control pressure (master cylinder pressure) Pm, and outputs a detection result to the ECU 71. A pressure sensor 78 that detects the reaction force hydraulic pressure Pf of the reaction force chamber R ₄ is provided on the fourth hydraulic pipe 134 on the third pressure port 133 side from the reaction force control valve 135, and the detection result is output to the ECU 71. ing. The communication pipe 137 is provided with a pressure sensor 76 that detects the hydraulic pressure supplied from the accumulator 42 to the communication pipe 137 via the pressure control valve 131, and outputs the detection result to the ECU 71. The front wheels FR and FL and the rear wheels RR and RL are provided with a wheel speed sensor 77 for detecting the wheel speed, and the detection result is output to the ECU 71.

Here, the braking force control by the vehicle braking device of the present embodiment will be specifically described. When the occupant steps on the brake pedal 15, the input piston 113 moves forward against the biasing force of the reaction force spring 117 via the operation rod 20 by the operation force. At this time, although the supply and discharge of the hydraulic pressure to the reaction force chamber R ₄ is stopped by the reaction force control valve 135, the rear pressure chamber R ₂ and the circulation pressure chamber R ₃ communicate with each other through the communication passage 121. The hydraulic pressure in the chamber R ₂ flows through the communication passage 121 to the circulation pressure chamber R ₃ , and the input piston 113 advances slightly.

  When the brake pedal 15 is depressed, the pedal effort sensor 73 detects the pedal effort Fp, and the ECU 71 sets the target control pressure Pmt based on the pedal effort Fp. Then, the ECU 71 controls the pressure control valve 131 based on the target control pressure Pmt, and outputs a predetermined control pressure.

That is, when the solenoid 156 is energized by the pressure control valve 131 and the drive valve 114 is moved by the generated electromagnetic force, the high pressure port P ₁ communicates with the control pressure port P ₃ via the communication path 157. Therefore, the hydraulic pressure of the accumulator 42 is supplied from the high pressure supply pipe 130 to the high pressure port P ₁ , supplied to the first pressure chamber R ₁₁ through the communication path 157, and second from the control pressure port P ₃ through the control pressure supply pipe 132. It is supplied to the hydraulic pipe 126. Then, the hydraulic pressure supplied to the second hydraulic pipe 126 is supplied from the second pressure port 125 of the master cylinder 111 to the annular pressure chamber R ₃ , acts on the rear pressure chamber R ₂ through the communication path 121, and is a pressure piston. 114 since the assist, the pressure piston 114 pressurizes the front pressure chamber R _1, the proper control pressure to the first hydraulic pipe 124 from the front pressure chamber R ₁ is discharged.

  Accordingly, control pressure is applied from the first hydraulic pipe 124 to the wheel cylinders 21FR and 21FL of the front wheels FR and FL, and control pressure is applied from the second hydraulic pipe 126 to the wheel cylinders 21RR and 21RL of the rear wheels RR and RL. Accordingly, a braking force corresponding to the operating force of the brake pedal 15 of the occupant can be generated for the front wheels FR, FL and the rear wheels RR, RL.

In this case, since the occupant performs an operation of depressing and returning the brake pedal 15 as necessary, the input piston 113 and the pressure piston 114 reciprocate back and forth according to the operation of the brake pedal 15 by the occupant. The pressurizing piston 114 may return to the initial position. However, in this embodiment, a hydraulic discharge pipe 141 that communicates the front pressure chamber R ₁ and the reservoir tank 33 is provided, and the hydraulic discharge pipe 141 is closed by an operating force input from the brake pedal 15 to the input piston 113. A shut-off valve 142 is provided.

Accordingly, in a state in which the occupant is applied an operating force to the input piston 113 by the brake pedal 15, the reaction force chamber R ₄ are pressurized, the movable element 84 of the oil pressure of the reaction chamber R ₄ shutoff valve 142 Acting on the hydraulic discharge pipe 141 to close it. Therefore, when the occupant is braking, the front pressure chamber R ₁ in the master cylinder 111 communicates are cut off the reservoir tank 33, the pressure piston 114 is also returned temporarily initial position, front The hydraulic pressure in the pressure chamber R ₁ is not discharged to the reservoir tank 33, and hunting of the pressurizing piston 114 is suppressed.

On the other hand, when a failure occurs in the power supply system, the braking hydraulic pressure applied to each wheel cylinder 21FR, 21FL, 21RR, 21RL is controlled to an appropriate hydraulic pressure by energizing the solenoid 156 of the pressure control valve 131. Can not do it. However, in this embodiment, an electromagnetic reaction force control valve 135 is provided in the fourth hydraulic pipe 134 connected to the third pressure port 133 of the reaction force chamber R ₄ , and the fourth hydraulic pipe 134 is not energized. Is opened and communicated with the reservoir tank 33.

Therefore, when the occupant steps on the brake pedal 15 at the time of failure of the power supply system, the input piston 113 moves forward against the urging force of the reaction force spring 117 via the operation rod 20 by the operation force. At this time, the reaction force control valve 135 from the hydraulic pressure supply and discharge for the reaction chamber R ₄ is allowed, the input piston 113 moves forward. In this case, when the input piston 113 advances by a predetermined stroke, the front surface of the input piston 113 comes into contact with the back surface of the pressurizing piston 114, so that the communication path 121 is closed by the seal member 122. Then, the pressure piston 114 moves forward together with the input piston 113, the Advancement of the pressure piston 114 by the front pressure chamber R ₁ is pressurized, the first hydraulic oil pressure of the front pressure chamber R ₁ is an external pressure It is discharged to the pipe 124 and discharged to the pressure control valve 131 through the external pressure supply pipe 139.

Then, the external pressure is applied to the second pressure chamber R ₁₂ from the external pressure supply pipe 139 via the external pressure port P ₄ by the pressure control valve 131, and the external piston 158 moves to press the drive valve 154. The high pressure port P ₁ communicates with the control pressure port P ₃ via the communication path 157. Therefore, the hydraulic pressure of the accumulator 42 is supplied from the high pressure supply pipe 130 to the high pressure port P ₁ , supplied to the first pressure chamber R ₁₁ through the communication path 157, and second from the control pressure port P ₃ through the control pressure supply pipe 132. It is supplied to the hydraulic pipe 126.

In this case, the external piston 158, since the pressure receiving area a ₁₁ in the first pressure chamber R ₁₁ is set larger than the pressure receiving area a ₁₂ second pressure chamber R _12, pressure control valve 131, front pressure chamber R _The driving force that presses the drive valve 154 with respect to the hydraulic pressure applied to the second pressure chamber R ₁₂ from ₁ decreases, and a lower hydraulic pressure than the hydraulic pressure discharged from the front pressure chamber R _{1 is} discharged to the external pressure supply pipe 139. Then, the control pressure from the pressure control valve 131 acts on the annular pressure chamber R ₃ from the second hydraulic pipe 126 to assist the pressurizing piston 114 via the input piston 113.

Therefore, the hydraulic pressure in the front pressure chamber R ₁ of the master cylinder 111 is increased and supplied to the front wheel side hydraulic supply pipes 25 a and 25 b through the first hydraulic pipe 124. That is, the braking hydraulic pressure is applied to the wheel cylinders 21FR and 21FL of the front wheels FR and FL, and a braking force corresponding to the operating force of the brake pedal 15 of the occupant can be generated on the front wheels FR and FL.

When a failure occurs in the power supply system, the servo ratio Rs of the master cylinder 111 is defined as follows.
Rs = [A ₁ − (A ₂ −A ₃ )] × (a ₁₂ / a ₁₁ )
A ₁ = A ₂ −A _{3
Rs = A 1 / (A 1} -A 1 × a 12 / a 11) = 1 / (1-a 12 / a 11) = a 11 / (a 11 -a 12)
a ₁₁ > a _{12
a 11 / (a 11 -a 12} )> A 1 / A 3

Thus, in the vehicle braking device of the second embodiment, the input piston 113 and the pressurizing piston 114 are movably supported in the cylinder 112, so that the front pressure chamber R ₁ , the rear pressure chamber R ₂ , the circulation The pressure chamber R ₃ and the reaction force chamber R ₄ are partitioned, the rear pressure chamber R ₂ and the circulating pressure chamber R ₃ are communicated by the communication passage 121, and this communication passage is provided when the input piston 113 approaches the pressurizing piston 114. The pressure control valve is provided with a seal member 122 that closes 121 and is provided in the pressurizing piston 114 and can output a control pressure obtained by adjusting the hydraulic pressure from the accumulator 42 from the circulation pressure chamber R ₃ to the rear pressure chamber R ₂ through the communication passage 121. 131 is provided.

Therefore, when failure of the power supply system, presses the input piston 113 pressure piston 114 in response to depression of the brake pedal 15, the front pressure chamber R ₁ by moving the pressure piston 114 is pressurized, the front pressure When the hydraulic pressure in the chamber R ₁ acts on the pressure control valve 131 as an external pressure, the hydraulic pressure increased by the pressure control valve 131 from the accumulator 42 acts on the annular pressure chamber R ₃ and is pressurized through the input piston 113. The piston 114 is assisted, and an appropriate control pressure can be supplied to the hydraulic pipes 124, 126. The appropriate control oil is applied to the wheel cylinders 21FR, 21FL, 21RR, 21RL via the ABS 22, and the front wheels An appropriate braking force corresponding to the operating force of the brake pedal 15 of the occupant can be generated for the FR, FL and the rear wheels RR, RL.

Further, in the vehicle braking device of the second embodiment, a hydraulic pressure discharge pipe 141 that can discharge the hydraulic pressure of the front pressure chamber R ₁ to the reservoir tank 33 when the pressurizing piston 114 is in the initial position is provided. 141 is provided with a shut-off valve 142 that is closed by an operating force input from the brake pedal 15 to the input piston 113. Accordingly, in a state where the occupant is applying an operating force to the input piston 113 by the brake pedal 15, the operating valve causes the shut-off valve 142 to close the hydraulic pressure discharge pipe 141, and the pressurizing piston 114 temporarily moves to the initial position. also, never hydraulic pressure in the front pressure chamber R ₁ is discharged into the reservoir tank 33, to improve drivability and improve the operability of the braking operation by hunting of the pressurizing piston 114 is suppressed back to In addition, an appropriate braking force can be secured and highly accurate braking force control can be performed.

In this case, shut-off valve 142 is designed so as to close the hydraulic pressure acting on the reaction force chamber R _4. Accordingly, in a state in which the occupant is applied an operating force to the input piston 113 by the brake pedal 15, the reaction force chamber R ₄ are pressurized, the movable element 84 of the oil pressure of the reaction chamber R ₄ shutoff valve 142 The hydraulic discharge pipe 141 is closed by acting on this, and the hunting of the pressurizing piston 114 can be suppressed with a simple configuration.

  FIG. 5 is a schematic configuration diagram illustrating a vehicle braking device according to a third embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  In the vehicular braking apparatus according to the third embodiment, as shown in FIG. 5, the master cylinder 211 has a backup pathton 213 and a pressurizing piston 214 arranged in series on the cylinder 212, and is movable along the axial direction. The input piston 215 is supported by the backup pathton 213 so as to be movable along the axial direction.

  The backup piston 213 is located inside the cylinder 212, has a cylindrical main body 216, a lid 217 fixed to one end of the main body 216 in the axial direction, and the other end of the main body 216 in the axial direction from the cylinder 212. It is comprised from the support part 218 which protrudes outside and makes | forms a cylindrical shape. The backup piston 213 is supported so that the outer peripheral surface of the main body 216 fits into the first inner peripheral surface 212a of the cylinder 212 and is movable along the axial direction. The backup piston 213 is integrally formed with a disc-shaped flange portion 213 a on the outer peripheral portion on the base end side of the main body 216, and the outer peripheral surface of the flange portion 213 a is the first inner peripheral surface 212 a of the cylinder 212. It fits into the second inner peripheral surface 212b having a larger diameter and is supported so as to be movable along the axial direction. Further, the backup piston 213 has a support portion 218 movably fitted in the through hole 219a of the support member 219, and the flange portion 213a is a step between the first inner peripheral surface 212a and the second inner peripheral surface 212b. By abutting on the portion 212c, the forward movement stroke is regulated, and when the flange portion 213a abuts on the support member 219, the backward movement stroke is regulated.

  The pressurizing piston 214 is disposed at the tip end side of the backup piston 213 in the cylinder 212, and the outer peripheral surface is movably supported by the first inner peripheral surface 212 a of the cylinder 212. Further, the pressurizing piston 214 is integrally formed with a flange portion 214 a, and the outer peripheral surface of the flange portion 214 a is supported movably on the third inner peripheral surface 212 d of the cylinder 212. Then, the movement stroke of the pressurizing piston 214 is restricted by the flange portion 214a coming into contact with the bottom portion of the cylinder 212 or the step portion 212e. The pressurizing piston 214 is urged and supported at a position where the flange portion 214a abuts on the step portion 212e by the urging force of the urging spring 221 interposed between the pressing plate 214 and the support plate 220.

  The input piston 215 has a cylindrical shape, and a pressing member 222 is fixed to a tip portion thereof. An outer peripheral surface of the input piston 215 is fitted to an inner peripheral surface of the backup piston 213 and is supported so as to be movable along the axial direction. A biasing spring 224 is interposed between the cover 217 of the backup piston 213 and the support plate 225, and the input piston 215 is biased in a direction away from the backup piston 213, and the backup piston 213. It is urged and supported at a position in contact with the step portion 213b.

  On the other hand, the operating rod 20 is connected to the brake pedal 15, the tip of the operating rod 20 enters the input piston 215 through the backup piston 213, and the connecting portion 20a is restrained by the locking portion 215a. , Connected to the input piston 215. An urging spring 226 is interposed between the cylinder 212 (support member 219) and the support plate 223 of the backup piston 213.

  Accordingly, when the pedal 17 is depressed, the brake pedal 15 rotates about the support shaft 16 as a fulcrum, and the operating force (pedal stroke) is transmitted to the input piston 215 via the operating rod 20, and the input piston 215 is energized. It can move forward against the urging force of the springs 224 and 226. In this case, when the occupant steps on the brake pedal 15, the input piston 215 moves forward via the operation rod 20, and the pressing member 222 moves forward against the biasing force of the biasing spring 224. A stroke simulator (operation force absorbing mechanism) is configured by 222, the urging spring 224, and the like.

Further, as described above, the backup piston 213, the pressurizing piston 214, and the input piston 215 are coaxially disposed in the cylinder 212 so as to be relatively movable, so that the front pressure chamber R ₁ , the rear pressure chamber R ₂ , The circulation pressure chamber R ₃ , the reaction force chamber R _4, and the pressure absorption chamber R ₅ are partitioned. The rear pressure chamber R ₂ and the circulation pressure chamber R ₃ are communicated with each other through a communication passage 227 formed in the cylinder 212.

On the other hand, the front wheels FR, FL and the rear wheels RR, RL are provided with wheel cylinders 21FR, 21FL, 21RR, 21RL, which can be operated by the ABS 22. That is, the first hydraulic pipe 124 is connected to the first pressure port 231 that communicates with the front pressure chamber R ₁ of the master cylinder 211. A second hydraulic pipe 126 is connected to the second pressure port 232 that communicates with the circulation pressure chamber R ₃ of the master cylinder 211. The third hydraulic pipe 32 is connected to the fourth pressure port 233 of the master cylinder 211, and is connected to the reservoir tank 33 from the fifth pressure port 234 via the hydraulic supply / discharge pipe 235. A fourth hydraulic pipe 134 is connected to the third pressure port 236 communicating with the reaction force chamber R ₄ of the master cylinder 211.

Further, the master cylinder 211, the supply and discharge port 237a communicating with the pressure absorbing chamber R _5, it is 237b are formed, is connected to the reservoir tank 33 through the hydraulic supply and discharge pipe 235. In this case, one-way seals 238 are attached before and after the supply / discharge port 237a in the cylinder 212. In this case, when the pressure absorption chamber (operation force absorption chamber) R ₅ is defined between the backup piston 213 and the input piston 215 and the backup piston 213 is held at the retracted position in contact with the support member 219. The pressure absorption chamber R ₅ communicates with the reservoir tank 33 through the hydraulic supply / discharge piping 235 from the supply / discharge ports 237a and 137b. Therefore, when the brake pedal 15 is depressed and the input piston 215 moves forward, the volume of the pressure absorption chamber R ₅ decreases and the hydraulic pressure is discharged to the reservoir tank 33, so that the operating force of the brake pedal 15 is absorbed. On the other hand, when the holding of the backup piston 213 is released, when the brake pedal 15 is depressed and the input piston 215 moves forward, the backup piston 213 moves forward together with the input piston 215. As a result, the supply / discharge port 237b of the backup piston 213 is displaced from the supply / discharge port 237a of the cylinder 212 and cannot communicate therewith. Therefore, the volume of the pressure absorption chamber R ₅ is not reduced, and the operating force of the brake pedal 15 is not absorbed and transmitted to the backup piston 213 via the input piston 215.

In addition, a hydraulic discharge pipe (discharge line) 241 that can discharge the hydraulic pressure of the front pressure chamber R ₁ to the reservoir tank 33 when the pressurizing piston 214 is in the initial position is provided, and the brake pedal 15 is connected to the hydraulic pressure discharge pipe 241. Is provided with a shut-off valve 242 that is closed by an operating force input to the input piston 215. In this embodiment, the shut-off valve 242 is configured to be closed by the hydraulic pressure acting on the reaction force chamber R ₄ .

  The shut-off valve 242 has the same configuration as the shut-off valves 82 and 142 of the above-described embodiments. The housing 83 includes a connection port 83a, a discharge port 83b, and an operation port 83c. The movable element 84 is supported so as to be movable, a communication hole 85 is formed in the movable element 84, and a ball valve 86 is attached to one end portion of the communication hole 85. The movable element 84 is biased and supported in a direction in which one end portion of the communication hole 85 is separated from the ball valve 86 by the biasing force of the biasing spring 87, and the movable element 84 resists the biasing force of the biasing spring 87. By moving, one end of the communication hole 85 can be brought into close contact with the ball valve 86 and the communication hole 85 can be closed.

At the master cylinder 211, the cylinder 212 and the pressing piston 214, ports 243a return to communicate with the front pressure chamber R _1, 243b is formed through, the cylinder 212 is communicated to the counterforce chamber R ₄ operation A port 244 is formed therethrough. The connection port 83a of the shut-off valve 242 is connected to the return port 243a via the connection pipe 81a of the hydraulic discharge pipe 241, and the discharge port 83b is connected to the reservoir tank 33 via the discharge pipe 81b. The operation port 83 c of the shut-off valve 242 is connected to the operation port 244 via the hydraulic operation pipe 245.

Therefore, when the pressurizing piston 214 is in the initial position, the movable element 84 of the shut-off valve 242 opens the communication hole 85 by separating one end of the communication hole 85 from the ball valve 86 by the biasing force of the biasing spring 87. ing. Therefore, the front pressure chamber R ₁ in the master cylinder 211 is communicated with the reservoir tank 33 through the return port 243a, 243b, connection pipe 81a, connecting ports 83a, communication holes 85, the discharge port 83 b, the exhaust pipe 81b. From this state, the input piston 215 moves forward, the counterforce chamber R ₄ is pressurized, the hydraulic actuation port 244 of the reaction force chamber R _4, hydraulic piping 245, the mover 84 through the operating ports 83c Works. Then, the mover 84 moves against the urging force of the urging spring 87, and one end portion of the communication hole 85 comes into contact with the ball valve 86 to close the communication hole 85. Therefore, the communication between the front pressure chamber R ₁ of the master cylinder 211 and the reservoir tank 33 can be blocked.

  Note that the ABS 22 of this embodiment is substantially the same as that of the second embodiment described above, and a description thereof will be omitted.

  Therefore, the ECU 71 sets the target control pressure Pmt based on the pedal depression force Fp of the brake pedal 15 detected by the pedal force sensor 73 (or the pedal stroke Sp detected by the stroke sensor 72), and the drive valve 154 in the pressure control valve 131 is set. The control pressure Pm detected by the first pressure sensor 74 is fed back, and the target control pressure Pmt and the control pressure Pm are controlled to coincide with each other. In this case, the ECU 71 has a control map representing the target control pressure Pmt with respect to the pedal depression force Fp, and drives and controls the pressure control valve 131 based on this control map.

Also, during normal operation of the power supply system for operating the pressure control valve 131 and the reaction force control valve 135, the pressure regulating the output hydraulic pressure by controlling the pressure control valve 131, against the reaction force chamber R ₄ by the reaction force control valve 135 Limit (stop) hydraulic supply and discharge. Therefore, when the brake pedal 15 is depressed by the occupant, the input piston 215 moves forward via the operation rod 20 and moves by pressing the backup piston 213. In this case, since the fourth hydraulic pipe 134 from the reaction force chamber R ₄ to the reaction force control valve 135 through the third pressure port 236 is a closed circuit, when the backup piston 213 advances slightly, the rear pressure chamber R ₂ flows through the communication path 227 to the circulation pressure chamber R ₃ , the input piston 215 advances relative to the backup piston 213, and the hydraulic pressure in the pressure absorption chamber R ₅ is discharged to the reservoir tank 33. .

On the other hand, when failure of the power supply system can not be electrically controlled pressure control valve 131, to allow the hydraulic supply and discharge for the reaction force chamber R ₄ by the reaction force control valve 135 (possible). Therefore, when the brake pedal 15 is depressed by the occupant, the input piston 215 moves forward via the operation rod 20 and the reaction force control valve 135 is in an open state, so that the backup piston 213 is pressed and the reaction force chamber R The hydraulic pressure ₄ is discharged from the third pressure port 236 through the reaction force control valve 135 to the reservoir tank 33, and the backup piston 213 moves forward to press the pressure piston 214.

By the way, during normal operation of the power supply system, the supply and discharge of the hydraulic pressure to the reaction force chamber R ₄ is restricted by the reaction force control valve 135, and the control pressure acts on the rear pressure chamber R ₂ from the accumulator 42 through the pressure control valve 131. Therefore, even if the brake pedal 15 is depressed by the occupant, the backup piston 213 does not move forward greatly. In this case, if the backup piston 213 is held at a position in contact with the support member 219 for a long period of time, the seal member and the like may be repeatedly fixed due to a change in temperature of the master cylinder 211 or the brake hydraulic pressure. .

Therefore, in normal operation of the power supply system, to determine the operating state of the master cylinder 211 to the backup piston 213 is actuated, in this case, to determine the malfunction of the backup piston 213 based on the hydraulic pressure of the reaction force chamber R ₄ I have to. That is, when the brake pedal 15 is depressed, since pressing the backup piston 213 advances the input piston 215 via the operating rod 20, reaction force chamber pressure of R ₄ the backup piston 213 is minutely forward fluctuation to reason, it is possible to determine the malfunction of the backup piston 213 based on the hydraulic pressure of the reaction chamber R _4.

In this case, it is necessary to set each oil passage area in the master cylinder 211 so that the following conditions are satisfied. In this case, the hydraulic pressure of the accumulator 42 is regulated by the pressure control valve 131, the brake pressure acting on the rear pressure chamber R ₂ and the circulation pressure chamber R ₃ of the master cylinder 211 by the control pressure supply pipe 132 is Pb, the second pressure sensor Pf is the reaction force hydraulic pressure of the reaction force chamber R ₄ detected by 75, Fp is the pedal depression force detected by the pedal force sensor 73, Abf is the front brake pressure area at the backup piston 213, Abr is the reaction pressure chamber R ₄ Let Afi be the area. Further, the oil passage area of the first inner peripheral surface 212a of the cylinder 212 in the master cylinder 211 is A1, the oil passage area of the second inner peripheral surface 212b is A2, and the area of the through hole 219a through which the backup piston 213 passes is A3. When
Front brake pressure area Abf = A1
Rear brake pressure area Abr = A2-A3
Reaction force chamber R ₄ area Afi = A2-A1
It becomes.

When the brake pedal 15 is depressed, the condition that the backup piston 213 moves and the hydraulic pressure in the reaction chamber R ₄ rises is a condition expressed by the following formula.
Fp + Pb × Abr> Pb × Abf
That is, it is only necessary to input an operation force greater than the pressure from the brake pedal 15 to the pressure at which the backup piston 213 is fixed. The reaction force hydraulic pressure Pf of the reaction force chamber R ₄ at this time can be obtained by the following mathematical formula.
Pf = (Fp + Pb × Abr−Pb × Abf) / Afi

Here, the braking force control by the vehicle braking device of the present embodiment will be specifically described. When the occupant steps on the brake pedal 15, the input piston 215 moves forward against the urging force of the urging spring 226 via the operation rod 20 by the operating force. At this time, although the supply and discharge of the hydraulic pressure to the reaction force chamber R ₄ is stopped by the reaction force control valve 135, the rear pressure chamber R ₂ and the circulation pressure chamber R ₃ are communicated with each other through the communication passage 227. The hydraulic pressure in the chamber R ₂ flows into the circulation pressure chamber R ₃ through the communication path 227, the backup piston 213 advances slightly, and the operating force is absorbed by the pressing member 222 deflecting the biasing spring 224.

  When the brake pedal 15 is depressed, the pedal effort sensor 73 detects the pedal effort Fp, and the ECU 71 sets the target control pressure Pmt based on the pedal effort Fp. Then, the ECU 71 controls the pressure control valve 131 based on the target control pressure Pmt, and outputs a predetermined control pressure.

That is, the solenoid 156 is energized by the pressure control valve 131, and the drive valve 154 is moved downward against the urging force of the return spring 155 by the generated electromagnetic force. Then, the high pressure port P ₁ and the control pressure port P ₃ communicate with each other through the communication passage 157 of the drive valve 154, while the pressure reduction port P ₂ and the control pressure port P ₃ are blocked. Therefore, the hydraulic pressure of the accumulator 42 is supplied from the high pressure supply pipe 130 to the high pressure port P ₁ , flows through the communication path 157 to the control pressure port P ₃ , and passes through the control pressure supply pipe 132 from the control pressure port P _3. It is supplied to the pipe 126. Then, the hydraulic pressure supplied to the second hydraulic pipe 126 acts on the rear pressure chamber R ₂ from the second pressure port 232 of the master cylinder 211 through the communication path 227 and assists the pressurizing piston 214. pressure piston 214 pressurizes the front pressure chamber R _1, the proper control pressure to the first hydraulic pipe 124 from the front pressure chamber R ₁ is discharged.

  Accordingly, control pressure is applied from the first hydraulic pipe 124 to the wheel cylinders 21FR and 21FL of the front wheels FR and FL, and control pressure is applied from the second hydraulic pipe 126 to the wheel cylinders 21RR and 21RL of the rear wheels RR and RL. Accordingly, a braking force corresponding to the operating force of the brake pedal 15 of the occupant can be generated for the front wheels FR, FL and the rear wheels RR, RL.

At this time, ECU 71, by the reaction force control valve 135 is closed, while the fourth hydraulic pipe 134 from the reaction chamber R ₄ to the reaction force control valve 135 through the third pressure port 236 is in the closed circuit Since the brake pedal 15 is depressed, it is determined whether or not the reaction force hydraulic pressure Pf in the reaction force chamber R ₄ detected by the pressure sensor 78 has increased. Here, ECU 71 When it is determined as the hydraulic pressure Pf of the counterforce chamber R ₄ increases, while determining that normally operates without sticking backup piston 213, the reaction force hydraulic pressure Pf of the counterforce chamber R ₄ If the backup piston 213 is fixed, the warning lamp is turned on because the backup piston 213 is stuck and is not operating normally. As described above, it is possible to easily determine the malfunction of the backup piston 213 based on the increase of the hydraulic pressure in the reaction force chamber R ₄ during the brake operation during the normal operation of the power supply system.

In addition, when a failure occurs in the power supply system, the reaction force control valve 135 is not energized to the fourth hydraulic pipe 134 connected to the third pressure port 236 of the reaction force chamber R ₄ . The fourth hydraulic pipe 134 is opened to communicate with the reservoir tank 33.

Therefore, when the occupant steps on the brake pedal 15 when the power supply system fails, the input piston 215 moves forward against the urging force of the urging spring 226 via the operation rod 20 by the operating force. At this time, since the supply and discharge of the hydraulic pressure to the reaction force chamber R ₄ is permitted by the reaction force control valve 135, the backup piston 213 moves forward together with the input piston 215. In this case, when the backup piston 213 by a predetermined stroke forward eliminates communicated deviated port 273b of the ports 273a and the backup piston 213 of the cylinder 212, the hydraulic pressure in the pressure absorbing chamber R ₅ not be discharged into the reservoir tank 33. Therefore, the input piston 215 can move the backup piston 213 appropriately.

When the backup piston 213 moves forward together with the input piston 215, the backup piston 213 presses the pressure piston 214, front pressure chamber R ₁ is pressurized by the pressurizing piston 214 moves forward, the front pressure chamber R ₁ hydraulic pressure is discharged to the first hydraulic pipe 124. The hydraulic pressure discharged from the front pressure chamber R ₁ to the first hydraulic pipe 124 acts as an external pressure on the external port P ₄ of the pressure control valve 131 through the external pressure supply pipe 139, thereby lowering the external piston 158 downward. And the drive valve 154 is moved downward. Then, as described above, the high pressure port P ₁ and the control pressure port P ₃ are communicated with each other by the communication passage 157 of the drive valve 154, and the hydraulic pressure of the accumulator 42 is regulated by the pressure control valve 131 and passes through the control pressure supply pipe 132. The pressure is supplied to the second hydraulic pipe 126 and acts on the rear pressure chamber R ₂ of the master cylinder 211 to assist the pressurizing piston 214.

  Therefore, even if the power supply system fails, the control pressure is applied from the first hydraulic pipe 124 to the wheel cylinders 21FR, 21FL of the front wheels FR, FL, and the wheel cylinders of the rear wheels RR, RL from the second hydraulic pipe 126. The control pressure is applied to 21RR and 21RL, and a braking force corresponding to the operating force of the brake pedal 15 of the occupant can be generated on the front wheels FR and FL and the rear wheels RR and RL.

As described above, in the vehicle braking apparatus according to the third embodiment, the backup piston 213, the pressurizing piston 214, and the input piston 215 are movably supported in the cylinder 212, so that the front pressure chamber R ₁ , the rear pressure chamber, and the like. R ₂ , circulation pressure chamber R ₃ , reaction force chamber R ₄ , and pressure absorption chamber R ₅ are partitioned, and the rear pressure chamber R ₂ and circulation pressure chamber R ₃ are communicated with each other through a communication passage 227 to adjust the hydraulic pressure from the accumulator 42. A pressure control valve 131 capable of outputting the compressed control pressure to the rear pressure chamber R ₂ and the wheel cylinders 21 RR and 21 RL is provided, and the supply and discharge of hydraulic pressure to the reaction force chamber R ₄ is controlled according to the operating state of the master cylinder 211. reaction force control valve 135 is provided, also, the pressure piston 214 is provided with oil pressure discharge line 241 can be discharged into the reservoir tank 33 the hydraulic pressure in the front pressure chamber R ₁ when in the initial position Both have a shut-off valve 242 is closed by the operation force inputted to the oil pressure discharge line 241 to the input piston 215 from the brake pedal 15 is provided.

Therefore, in a state where the occupant applies operating force to the input piston 215 by the brake pedal 15, the shut-off valve 242 closes the hydraulic pressure discharge pipe 241 by this operating force, and the pressurizing piston 214 is temporarily moved to the initial position. also, never hydraulic pressure in the front pressure chamber R ₁ is discharged into the reservoir tank 33, to improve drivability and improve the operability of the braking operation by hunting of the pressurizing piston 214 is suppressed back to In addition, an appropriate braking force can be secured and highly accurate braking force control can be performed.

  FIG. 6 is a schematic configuration diagram illustrating a vehicle braking device according to a fourth embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 6, the vehicle braking device of the fourth embodiment has a configuration that is substantially the same as that of the second embodiment described above. In this embodiment, the shut-off valve is built in the stroke simulator.

That is, a hydraulic pressure discharge pipe 141 that can discharge the hydraulic pressure of the front pressure chamber R ₁ to the reservoir tank 33 when the pressure piston 114 is in the initial position is provided, and the input piston 113 is connected to the hydraulic pressure discharge pipe 141 from the brake pedal 15. A stroke simulator 311 having a built-in shut-off valve that is closed by an operating force input to the input is provided.

  In the stroke simulator 311, a connection port 312 a, a discharge port 312 b, and an operation port 312 c are formed in the housing 312, and a support member 313 and a mover 314 are supported in a movable manner in series. A communication hole 315 is formed in the mover 314, and a ball valve 316 is attached to the support member 313 so as to face one end of the communication hole 135. Further, an elastic member 317 is interposed between the housing 312 and the support member 313, while an urging spring 318 is avoided between the support member 313 and the mover 134. One end portion of the communication hole 315 is urged and supported in a direction away from the ball valve 316 by the urging force of the urging spring 318, and the movable element 314 moves against the urging force of the urging spring 318. One end of 315 can be in close contact with the ball valve 316 to close the communication hole 315.

At the master cylinder 111, the cylinder 112 and the pressure piston 114, ports 143a return to communicate with the front pressure chamber R _1, 143b is formed through, the cylinder 112 is communicated to the counterforce chamber R ₄ operation A port 144 is formed to penetrate therethrough. The connection port 312a of the stroke simulator 311 is connected to the return port 143a via the connection pipe 141a of the hydraulic pressure discharge pipe 141, and the discharge port 312b is connected to the reservoir tank 33 via the discharge pipe 141b. The operation port 312 c of the stroke simulator 311 is connected to the operation port 144 via a hydraulic operation pipe 319.

Therefore, when the pressurizing piston 114 is in the initial position, the mover 314 of the stroke simulator 311 opens the communication hole 315 by separating one end of the communication hole 315 from the ball valve 316 by the urging force of the urging spring 318. ing. Therefore, the front pressure chamber R ₁ in the master cylinder 111 is communicated with the reservoir tank 33 through the return port 143a, 143b, connecting tube 141a, connection port 312a, communication hole 315, the discharge port 312b, the discharge pipe 141b. From this state, the input piston 113 moves forward, the counterforce chamber R ₄ is pressurized, the hydraulic actuation port 144 of the reaction force chamber R _4, hydraulic piping 319, the mover 314 via the operating ports 312c Works. Then, the mover 314 moves against the urging force of the urging spring 318, and one end of the communication hole 315 comes into contact with the ball valve 316 to close the communication hole 315. Therefore, the communication between the front pressure chamber R ₁ of the master cylinder 111 and the reservoir tank 33 can be blocked.

  Note that the braking force control by the vehicle braking device of the present embodiment is the same as that of the second embodiment described above, and thus the description thereof is omitted.

As described above, in the vehicle braking apparatus of the fourth embodiment, the hydraulic discharge pipe 141 that can discharge the hydraulic pressure of the front pressure chamber R ₁ to the reservoir tank 33 when the pressurizing piston 114 is in the initial position is provided. A stroke simulator 311 is provided in the hydraulic pressure discharge pipe 141, and a shut-off valve that is closed by an operating force input from the brake pedal 15 to the input piston 113 is built in the stroke simulator 311.

Therefore, in a state where the occupant is applying an operating force to the input piston 113 by the brake pedal 15, the movable element 314 closes the hydraulic pressure discharge pipe 141 by this operating force, and the pressurizing piston 114 temporarily moves to the initial position. also, never hydraulic pressure in the front pressure chamber R ₁ is discharged into the reservoir tank 33, to improve drivability and improve the operability of the braking operation by hunting of the pressurizing piston 114 is suppressed back to In addition, an appropriate braking force can be secured and highly accurate braking force control can be performed.

  In this case, the shut-off valve is built in the stroke simulator 311. Therefore, the apparatus can be reduced in size, the mounting property to the vehicle can be improved, and the cost can be reduced.

  FIG. 7 is a schematic configuration diagram illustrating a vehicle braking device according to a fifth embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 7, the vehicle braking device of the fifth embodiment has a configuration that is substantially the same as that of the third embodiment described above. In this embodiment, the shutoff valve is an orifice.

That is, a hydraulic pressure discharge pipe (discharge line) 141 capable of discharging the hydraulic pressure of the front pressure chamber R ₁ to the reservoir tank 33 when the pressurizing piston 114 is in the initial position is provided, and the brake pedal 15 is connected to the hydraulic pressure discharge pipe 141. Is provided with a shut-off valve 411 that is closed by an operating force input to the input piston 113.

  In the shut-off valve 411, a connection port 412a and a discharge port 412b are formed in the housing 412. A movable element 413 is movably supported therein, and an orifice 414 as a communication hole is formed in the movable element 413. A ball valve 415 is mounted to face one end of the orifice 414. The movable element 413 is urged and supported in a direction in which one end of the orifice 414 is separated from the ball valve 415 by the urging force of the urging spring 416, and the movable element 413 moves against the urging force of the urging spring 416. By doing so, one end of the orifice 414 can be brought into close contact with the ball valve 415 and the orifice 414 can be closed.

At the master cylinder 111, the cylinder 112 and the pressure piston 114, ports 143a return to communicate with the front pressure chamber R _1, 143b is formed through, the cylinder 112 is communicated to the counterforce chamber R ₄ operation A port 144 is formed to penetrate therethrough. The connection port 412a of the shut-off valve 411 is connected to the return port 143a through the connection pipe 141a of the hydraulic discharge pipe 141, and the discharge port 412b is connected to the reservoir tank 33 through the discharge pipe 141b.

Therefore, when the pressurizing piston 114 is in the initial position, the mover 413 of the shut-off valve 411 opens the orifice 414 by separating one end of the orifice 414 from the ball valve 415 by the biasing force of the biasing spring 416. . Therefore, the front pressure chamber R ₁ in the master cylinder 111 is communicated with the reservoir tank 33 through the return port 143a, 143b, connecting tube 141a, connection port 412a, the orifice 414, the discharge port 412b, the discharge pipe 141b. In this state, the pressure piston 114 via the input piston 113 pressurized front pressure chamber R ₁ is pressurized when advanced, the hydraulic pressure return port 143a of the front pressure chamber R _1, 143b, connecting pipe 141a, the connection port 412a Acting on the orifice 414. Then, the mover 413 moves against the urging force of the urging spring 416 by the hydraulic pressure in the front pressure chamber R ₁ , and one end of the orifice 414 comes into contact with the ball valve 415 to close the orifice 414. Therefore, the communication between the front pressure chamber R ₁ of the master cylinder 111 and the reservoir tank 33 can be blocked.

  Note that the braking force control by the vehicle braking device of the present embodiment is the same as that of the second embodiment described above, and thus the description thereof is omitted.

As described above, in the vehicle braking device of the fifth embodiment, the hydraulic discharge pipe 141 that can discharge the hydraulic pressure of the front pressure chamber R ₁ to the reservoir tank 33 when the pressurizing piston 114 is in the initial position is provided. The hydraulic pressure discharge pipe 141 is provided with a shut-off valve 411 that self-closes by an operating force input from the brake pedal 15 to the input piston 113.

Accordingly, in a state where the occupant is applying an operating force to the input piston 113 by the brake pedal 15, the operating valve causes the shut-off valve 411 to close the hydraulic pressure discharge pipe 141, and the pressurizing piston 114 temporarily moves to the initial position. also, never hydraulic pressure in the front pressure chamber R ₁ is discharged into the reservoir tank 33, to improve drivability and improve the operability of the braking operation by hunting of the pressurizing piston 114 is suppressed back to In addition, an appropriate braking force can be secured and highly accurate braking force control can be performed.

In this case, the movable element 413 of the shutoff valve 411 is provided with an orifice 414 that self-closes by the hydraulic pressure from the front pressure chamber R ₁ , that is, the fluid force. Therefore, it is possible to reduce the size of the apparatus by reducing the number of hydraulic pipes, improve the mountability on the vehicle, and reduce the cost.

In each of the above-described embodiments, the hydraulic discharge pipes 81 and 141 that can discharge the hydraulic pressure of the front pressure chamber R ₁ to the reservoir tank 33 when the driving piston 13 or the pressurizing pistons 114 and 214 are in the initial position are provided. The hydraulic discharge pipes 81 and 141 are provided with a shut-off valve 82 that is closed by the hydraulic pressure of the rear pressure chamber R ₂ and the reaction force chamber R ₄ , a shut-off valve built in the stroke simulator 311, and the hydraulic pressure of the front pressure chamber R ₁ . However, the present invention is not limited to this configuration, and any shut-off valve may be used as long as the shut-off valve is closed by an operation force input from the brake pedal 15.

As described above, the vehicular braking apparatus according to the present invention can improve drivability by ensuring appropriate braking force and enabling highly accurate braking force control and improving the operability of braking operation. It is suitable for any type of braking device.

1 is a schematic configuration diagram illustrating a vehicle braking device according to a first embodiment of the present invention. It is sectional drawing of the pressure control valve in the brake device for vehicles of Example 1. FIG. It is a schematic block diagram showing the vehicle braking device which concerns on Example 2 of this invention. It is sectional drawing of the pressure control valve in the brake device for vehicles of Example 2. FIG. It is a schematic block diagram showing the vehicle braking device which concerns on Example 3 of this invention. It is a schematic block diagram showing the vehicle braking device which concerns on Example 4 of this invention. It is a schematic block diagram showing the vehicle braking device which concerns on Example 5 of this invention.

Explanation of symbols

11, 111, 211 Master cylinder 12, 112, 212 Cylinder 13 Drive piston 14, 117, 226 Reaction spring 15 Brake pedal (operation member)
20 Operating rod 21FR, 21FL, 21RR, 21RL Wheel cylinder 22 ABS
24,124 First hydraulic piping 28,126 Second hydraulic piping 32 Third hydraulic piping 33 Reservoir tank 38 Hydraulic pump (hydraulic supply source)
42 Accumulator (hydraulic supply source)
43, 130 High pressure supply pipe 44, 131 Pressure control valve 45, 132 Control pressure supply pipe 46, 139 External pressure supply pipe 47 Reduced pressure supply pipe 56, 154 Drive valve 58, 158 External piston 71 Electronic control unit, ECU (control pressure setting) means)
72 Stroke sensor 73 Treading force sensor 74 First pressure sensor 75 Second pressure sensor 76 Pressure sensor 78 Pressure sensor 81, 141, 235 Hydraulic discharge pipe (discharge line)
82, 142, 242, 411 Shut-off valve 84, 314, 413 Mover 113, 215 Input piston (drive piston)
114, 214 Pressurized piston (drive piston)
121 communication path 135 reaction force control valve 136, 311 stroke simulator 213 backup piston 414 orifice (communication hole)
R ₁ front pressure chamber R ₂ rear pressure chamber R ₃ circulation pressure chamber R ₄ reaction force chamber R ₅ pressure absorption chamber R ₁₁ first pressure chamber R ₁₂ second pressure chamber R ₁₃ decompression chamber P ₁ high pressure port P ₂ decompression port P ₃ Control pressure port P ₄ External pressure port

Claims (3)

The front pressure chamber and the rear pressure chamber are partitioned by the operation member that the occupant brakes and the drive piston is movably supported in the cylinder, and the front piston is moved by moving the drive piston by the operation member. Connected to the master cylinder capable of outputting the hydraulic pressure of the chamber, control pressure setting means for setting a target control pressure corresponding to the operating force input from the operating member to the drive piston, a hydraulic pressure supply source, and the front pressure chamber The wheel cylinder that generates a braking force on the wheel and the drive valve is moved by electromagnetic force based on the target control pressure to adjust the hydraulic pressure from the hydraulic pressure supply source and output it to the rear pressure chamber. A pressure control valve; a discharge line capable of discharging the hydraulic pressure in the front pressure chamber when the drive piston is in an initial position; and a front line provided on the discharge line from the operation member. And a shut-off valve which closes by the operation force inputted to the drive piston,
The vehicular braking apparatus , wherein the shut-off valve is closed by hydraulic pressure acting on the rear pressure chamber by the pressure control valve . The shut-off valve has a movable element for closing the discharge line by operation force input from the operation member to the driving piston, movable element is claimed in claim 1, characterized in that the function as a stroke simulator Vehicle braking system. The vehicle brake device according to claim 1 or 2 , wherein the wheel cylinder on the front wheel side is connected to the front pressure chamber, and the wheel cylinder on the rear wheel side is connected to the rear pressure chamber.

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