JP2684085B2 - Braking hydraulic control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention (1) Field of Industrial Application The present invention has a control port having an output port for outputting a hydraulic pressure according to a braking operation amount and the output port being connected to a brake device. Brake oil pressure generating means; an operating piston that is interlocked with and linked to a brake pedal so as to move forward in response to a braking operation, is slidably fitted in a housing, and an operating piston that contracts its volume in response to forward movement of the operating piston. A hydraulic pressure generating means in which a hydraulic pressure chamber is formed in the housing so as to face the front end face of the hydraulic pressure generating means; and a pressure accumulating chamber communicating with the hydraulic pressure chamber of the hydraulic pressure generating means and an urging force in a direction of contracting the volume of the pressure accumulating chamber. And a stroke accumulator having a reaction force spring.

(2) Conventional Technology Conventionally, in such a braking hydraulic device, the depression stroke of the brake pedal is stored by accumulating the hydraulic pressure output from the hydraulic pressure chamber of the hydraulic pressure generation means in accordance with the depression operation of the brake pedal in the accumulator chamber of the stroke accumulator. Secure,
The hydraulic pressure output from the output port of the control brake hydraulic pressure generation means is applied to the brake device.

(3) Problems to be Solved by the Invention However, in the conventional stroke accumulator, only the reaction force spring exerts the biasing force in the direction of contracting the volume of the pressure accumulating chamber, and the reaction force spring is relatively large. Therefore, the stroke accumulator is inevitably increasing in size. Further, since the reaction force acting on the brake pedal is determined only by the characteristic of the reaction force spring, it is hard to say that the operation feeling of the brake pedal is excellent.

The present invention has been made in view of such circumstances,
An object of the present invention is to provide a braking hydraulic pressure control device that enables downsizing of a stroke accumulator and improves operation feeling of a brake pedal.

B. Configuration of the Invention (1) Means for Solving the Problems In order to achieve the above object, the present invention has an output port for outputting a hydraulic pressure according to a braking operation amount, and the output port is connected to a brake device. Control brake oil pressure generating means; and an operating piston that is interlocked with and linked to a brake pedal to move forward in response to a braking operation, is slidably fitted in a housing, and contracts in volume in response to forward movement of the operating piston. A hydraulic pressure generating means in which a hydraulic pressure chamber is formed in the housing so as to face the front end face of the working piston; a pressure accumulating chamber communicating with the hydraulic pressure chamber of the hydraulic pressure generating means, and a biasing force in a direction of contracting the volume of the pressure accumulating chamber. And a stroke accumulator having a reaction force spring that exerts a force; and a back pressure chamber of the stroke accumulator,
An output port of the control brake hydraulic pressure generating means is connected.

(2) Operation According to the above configuration, the hydraulic pressure from the control brake hydraulic pressure generating means is given to the brake device in accordance with the braking operation, and at that time, the hydraulic pressure generated by the hydraulic pressure generating means is stored in the pressure accumulator chamber of the stroke accumulator, The stroke of the brake pedal is secured. Moreover, since the output hydraulic pressure of the control brake hydraulic pressure generating means acts on the back pressure chamber of the stroke accumulator, the urging force in the direction of contracting the pressure accumulator in the stroke accumulator is the spring force of the reaction force spring and the back pressure chamber. It is the resultant force of the hydraulic pressure that acts, and the reaction spring can be downsized to reduce the size of the stroke accumulator. Also, as part of the biasing force, the output hydraulic pressure of the control brake oil pressure generation means according to the braking operation can be reduced. By using, the stroke reaction force characteristic of the brake pedal can be improved.

(3) Example Hereinafter, one example in which the present invention is applied to a front-wheel drive vehicle will be described with reference to the drawings.

Brake device for front left wheel on front left and front right wheels of vehicle
B _FL and the brake B _FR for the right front wheel are installed respectively, and the brake device B _RL for the left rear wheel and the brake device B _RR for the right rear wheel are installed respectively on the left rear wheel and the right rear wheel. On the other hand, the brake pedal 1 has a control brake oil pressure generating means 3 for controlling the oil pressure of the oil pressure supply source 2 in accordance with the braking operation amount.
Is connected, and during normal braking, the hydraulic pressure from the control brake hydraulic pressure generating means 3 is increased by the one-way hydraulic pressure transmitting means 4 _FL , 4 _FR and is given to the front wheel brake devices B _FL , B _FR . The hydraulic pressure after controlling the hydraulic pressure from the control brake hydraulic pressure generating means 3 with the proportional pressure reducing valve 5 is the one-way hydraulic pressure transmitting means 4
_The pressure is increased by _RL , 4 _RR and applied to each rear wheel braking device B _RL , B _RR . Further, a hydraulic pressure generating means 6 for outputting a hydraulic pressure according to the depression amount of the brake pedal 1 is interlocked and connected to the control brake hydraulic pressure generating means 3, and when the hydraulic pressure supply source 2 becomes out of order, the hydraulic pressure generating means 6 is generated. The hydraulic pressure generated at is applied to each brake device B _FL , B _FR , B _RL , B _RR . Provided commonly to individual inlet valve 7 _FL provided corresponding, 7 _FR and the outlet valve 8 _FL, 8 _FR and the rear wheels brake device B _RL, B _RR and each front wheel brake device B _FL, the B _FR The inflow valve 7 _R and the outflow valve 8 _R can hold or reduce the braking hydraulic pressure of each brake device B _FL , B _FR , B _RL , B _RR to perform antilock control, and the traction control inflow valve 9 and The traction control outflow valve 10 can increase the braking hydraulic pressure of each of the brake devices B _FL , B _FR , B _RL , and B _RR during non-braking to perform traction control.

The hydraulic supply source 2 includes a hydraulic pump 11 for pumping hydraulic oil from the reservoir R, an accumulator 12 connected to the hydraulic pump 11, and a pressure switch 13 for controlling the operation of the hydraulic pump 11.

The control brake oil pressure generating means 3 has one end in the axial direction of the end wall 15
A first housing 15 forming a first cylinder hole 16 closed by a, a pressure piston 17 slidably fitted in the first cylinder hole 16, and a biasing force of the pressure piston 17 toward one end in the axial direction. Therefore, a spring 18 compressed between the first housing 15 and the pressure piston 17, an annular input hydraulic chamber 19 defined between the pressure piston 17 and the first housing 15 while communicating with the hydraulic supply source 2, An annular output hydraulic chamber 20 defined between the pressure piston 17 and the first housing 15 adjacent to the input hydraulic chamber 19 and fitted to the pressure piston 17 while being connected to the brake pedal 1 so as to be relatively slidable in the axial direction. Depending on the relative movement of the reaction force piston 21 and the first and second control hydraulic chambers 22a and 22b defined between the pressure piston 17 and the reaction force piston 21, and the reaction force piston 21 and the pressure piston 17 Reaction force piston 21 and pressure piston to open and close An inlet valve 23 and an outlet valve 24 provided between the tonnes 17 are provided.

Two annular grooves are provided on the outer surface of the pressure piston 17 to define an input hydraulic chamber 19 and an output hydraulic chamber 20 between the inner surface of the first housing 15 and the input hydraulic chamber 19 and the output hydraulic chamber 20. Are sealed between the pressure piston 17 and the first housing 15 on both axial sides. A spring chamber 25 is formed between the pressure piston 17 and the other end of the first housing 15. The spring 18 housed in the spring chamber 25 causes the pressure piston 17 to move in one axial direction (to the right in the drawing). Be energized.

The first housing 15 is provided with an input port 26 communicating with the input hydraulic chamber 19, an output port 27 communicating with the output hydraulic chamber 20, and a release port 28 communicating with the spring chamber 25, regardless of the axial position of the pressure piston 17. The input port 26 is connected to the hydraulic pressure source 2 and the release port 28 is connected to the reservoir R.

The pressure piston 17 is coaxially formed with a bottomed sliding hole 29 opened at one end in the axial direction, and the reaction piston 21 is slidably fitted into the sliding hole 29. The rear end of the reaction force piston 21 is connected to the tip of a pressing rod 30 which is pressed and driven by the brake pedal 1.
Is axially driven by the brake pedal 1. In addition, the first between the tip of the reaction force piston 21 and the closed end of the sliding hole 29
A control hydraulic chamber 22a is defined, and an annular second control hydraulic chamber 22b is defined between the inner surface near the rear end of the pressure piston 17 and the outer surface near the rear end of the reaction force piston 21. The reaction force piston 21 is provided with a communication passage 31 communicating between the first and second control hydraulic chambers 22a and 22b, and the first control hydraulic chamber 22a is always in communication with the output hydraulic chamber 20. Further, the first control hydraulic chamber 22a accommodates a spring 32 that resiliently biases the reaction piston 21 in a direction in which the volumes of the first and second control hydraulic chambers 22a and 22b increase.

The inlet valve 23 communicates with the input hydraulic chamber 19 and opens into the inner surface of the sliding hole 29, and is provided with a valve hole 33 formed in the pressure piston 17;
The reaction force piston 21 communicates with the communication passage 31 and opens to the outer surface.
And a valve hole 34 formed in the valve hole 34.When the positions of the valve holes 33, 34 are shifted in the axial direction, the valve is closed, and the valve holes 33, 34 are located at positions corresponding to each other. When it becomes, the valve is opened. Further, the outlet valve 24 communicates with the spring chamber 25 and opens on the inner surface of the sliding hole 29, and a valve hole 35 formed in the pressure piston 17. And a valve hole 36 formed in the piston 21.When the positions of the valve holes 35, 36 are shifted, the valve is closed, and the valve holes 35, 36 The valve is opened when it becomes.

As shown in the drawing, the inlet valve 23 is closed and the outlet valve 24 is open when the pressure piston 17 is at the retreat limit position and the reaction force piston 21 is also at the retreat limit position. When the reaction piston 21 moves forward from this state, the outlet valve 24 closes and then the inlet valve 23 opens. As a result, when the pressure in the first and second control hydraulic chambers 22a and 22b increases and the pressure piston 17 advances relatively to the reaction piston 21, the outlet valve 24 opens and the inlet valve 23 closes. I do.

In this way, in the control brake oil pressure generating means 3, the reaction force piston 21 and the pressure piston 17 alternately move relative to each other in response to the depression operation of the brake pedal 1, whereby the depression amount of the brake pedal 1 into the output hydraulic chamber 20. A hydraulic pressure proportional to is generated. Further, when the hydraulic pressure from the hydraulic pressure supply source 2 is abnormally lowered for some reason, the reaction force piston 21 moves forward in response to the depression operation of the brake pedal 1, so that the reaction force piston 21 comes into contact with the pressure piston 17 and the pressure is increased. The piston 17 is pushed by the reaction force piston 21 to move forward.

The hydraulic pressure generating means 6 is known as a tandem type master cylinder, and the control brake hydraulic pressure generating means 3 is used.
The second housing 40 integrated with the first housing 15 of FIG. The second housing 40 is provided with a second cylinder hole 42 that is coaxial with the first cylinder hole 16 with the partition wall 41 interposed therebetween, and the other end, that is, the front end of the second cylinder hole 42 is closed. In the second cylinder hole 42, the first hydraulic chamber is formed between the second cylinder hole 42 and the front end wall.
The first working piston 44 on the front side that forms 43 and the second working piston 46 that forms the second hydraulic chamber 45 between the first working piston 44 are slidably fitted together, and the second housing 40 A spring 47 for biasing the first working piston 44 to the rear side is interposed between the front end wall of the first working piston 44 and the first working piston 44, and the first working piston 44 and the second working piston 46 are provided with a first spring 47. A spring 48 that biases the two-acting piston 46 to the rear side is provided. The second housing 40 is provided with a first output port 38 communicating with the first hydraulic chamber 43 and a second output port 39 communicating with the second hydraulic chamber 45.

A front end of a piston rod 50 extending rearward is fixed to the second working piston 46.
The reference numeral 50 penetrates through the partition wall 41 in an oiltight and movably manner, and the front end of a pressing pin 17a provided coaxially on the front end of the pressure piston 17 in the control brake hydraulic pressure generating means 3 is brought into coaxial contact with the piston rod 50. . Therefore, the second working piston 46 is also pushed forward in response to the forward movement of the pressure piston 17 in the control brake hydraulic pressure generating means 3.

A refill oil chamber 51 is defined between the inner surface of the second cylinder hole 42 and the first working piston 44, and a connection port 52 is formed in the second housing 40 to connect the refill oil chamber 51 to the reservoir R. . Moreover, the first working piston 44 has a second cylinder hole.
A cup seal 53 slidingly in contact with the inner surface of 42 is fitted,
The cup seal 53 and the first working piston 44 are connected to each other when the first hydraulic chamber 43 is depressurized more than the refill oil chamber 51.
It is configured to allow the flow of hydraulic oil from 51 to the first hydraulic chamber 43. Further, a supply oil chamber 54 is defined between the partition wall 41 and the second working piston 46, and a connection port 55 for communicating the supply oil chamber 54 with the reservoir R is provided in the second housing 40. A cup seal 56 that slides on the inner surface of the second cylinder hole 42 is fitted to the second working piston 46. The cup seal 56 and the second working piston 46
When the pressure in the second hydraulic chamber 45 is reduced, the flow of the hydraulic oil from the supply oil chamber 54 to the second hydraulic chamber 45 is allowed.

A valve mechanism which is opened and closed by a stopper pin 57 fixed to the second housing 40 is provided at a front portion of the first working piston 44.
A valve 58 is provided to communicate and shut off between the first working hydraulic chamber 43 and the replenishing oil chamber 52. The valve mechanism 58 is pressed by the stopper pin 57 when the first working piston 44 returns to the retreat limit. The valve is opened. At the front of the second working piston 46, a valve mechanism 60 driven to be opened and closed by a stopper pin 59 is provided so as to communicate and cut off between the second working hydraulic chamber 45 and the replenishing oil chamber 54. The stopper pin 59 is substantially integrated with the second housing 40, and the valve mechanism 60 opens when the second working piston 46 returns to the retreat limit.

In the hydraulic pressure generating means 6, the second working piston 46 is pressed forward by the forward movement of the pressure piston 17 according to the depression of the brake pedal 1, and accordingly the volumes of the first hydraulic chamber 43 and the second hydraulic chamber 45 are increased. Contracted and hydraulic chambers 43,4 of them
The braking hydraulic pressure generated at 5 is applied to the first and second output ports 38, 39.
Is output from each.

The one-way hydraulic pressure transmission means 4 _FL , 4 _FR , 4 _RL , 4 _RR are brake devices from the hydraulic pressure supply source 2 through the control brake hydraulic pressure generation means 3.
B _FL , B _FR , B _RL , B _RR are provided in the middle of the hydraulic path, and the one-way hydraulic pressure transmission means 4 _FL , 4 _FR are between the control brake hydraulic pressure generation means 3 and the braking device B _FL , B _FR. In addition, the one-way hydraulic pressure transmission means 4 _RL , 4 _RR are provided between the proportional pressure reducing valve 5 and the brake devices B _RL , B _RR . These one-way hydraulic pressure transmitting means 4 _FL , 4 _FR , 4 _RL , 4 _{RR apply} the hydraulic pressure from the control brake hydraulic pressure generating means 3 to each brake device B _FL , B _FR when the hydraulic pressure from the hydraulic pressure source 2 is normal. , B _RL , B _RR , but when the hydraulic pressure of the hydraulic pressure source 2 drops abnormally, the hydraulic oil flows backward from each brake device B _FL , B _FR , B _RL , B _RR to the hydraulic pressure source 2 side. Which has the function of blocking
Since they have basically the same configuration, the configuration of the one-way hydraulic pressure transmission means 4 _FL will be described below as a representative.

The one-way hydraulic transmission means 4 _FL has an input chamber 63 and an output chamber 64.
The free piston 65 moves to the cylinder body 66 with both ends facing
A spring 67 is slidably fitted to the output chamber 64 and biases the free piston 65 toward the input chamber 63. Moreover, the pressure receiving area S ₁ of the free piston 65 facing the input chamber 63 is set larger than the pressure receiving area S ₂ facing the output chamber 64.

According to such a configuration of the one-way hydraulic transmission means 4 _FL ,
The oil pressure acting on the input chamber 63 can be increased and output from the output chamber 64, and the oil pressure in the output chamber 64 can be increased.
It does not flow to the side and the output chamber 64 is connected to the braking device B _FL .

That is, the brake devices B _FL , B _FR , B _RL , and B _{RR each} include a cylinder body 68 and a piston 69 slidably fitted in the cylinder body 68, and the cylinder body 68 and the piston 69.
The braking force is exerted by the movement of the piston 69 according to the hydraulic pressure acting on the braking hydraulic chamber 70 defined between the output chamber 64 and the braking hydraulic chamber 70.

Inflow valves 7 _FL , 7 _FR and outflow valves 8 _FL , 8 _FR are connected in parallel to the input chamber 63 of the one-way hydraulic transmission means 4 _FL , 4 _FR corresponding to the front wheel braking device B _FL , B _FR. is, the rear wheel brake device B _RL, unidirectional hydraulic transmission means 4 corresponding to the B _{RR RL,} 4 _RR
The output port 72 of the proportional pressure reducing valve 5 is commonly connected to the input chamber 63, and the inflow valve 7 _R and the outflow valve 8 _R are connected in parallel to the input port 73 of the proportional pressure reducing valve 5.

The inflow valves 7 _FL , 7 _FR , 7 _R are solenoid valves that are turned off when energized, and the outflow valves 8 _FL , 8 _FR , 8 _R are solenoid valves that are turned on when energized. Thus, the outflow valves 8 _FL , 8 _FR are provided between the input chamber 63 and the reservoir R of the one-way hydraulic transmission means 4 _FL , 4 _FR , and the outflow valve 8 _R is the input port 73 of the proportional pressure reducing valve 5 and the reservoir R. It is installed in between. Further, the inflow valves 7 _FL , 7 _FR are provided between the input chamber 63 and the oil passage 71 of the one-way hydraulic transmission means 4 _FL , 4 _FR , and the inflow valve 7 _R is the input port 73 of the proportional pressure reducing valve 5 and the oil passage.
It is installed between 71.

The proportional pressure reducing valve 5 has a conventionally well-known structure, and includes a valve body 74 having the output port 72 and the input port 73, an output hydraulic chamber 75 communicating with the output port 72, and an input hydraulic chamber communicating with the input port 73. A piston 77 slidably fitted to the valve body 74 with both ends facing the valve 76, a spring 78 housed in the input hydraulic chamber 76 to bias the piston 77 toward the output hydraulic chamber 75, A valve mechanism 79 is provided on the piston 77 so as to communicate between the input hydraulic chamber 76 and the output hydraulic chamber 75 in accordance with the movement of the 77 to the output hydraulic chamber 75 side. Moreover, the pressure receiving area facing the input hydraulic chamber 76 of the piston 77 is the output hydraulic chamber.
It is set smaller than the pressure receiving area facing 75.

According to the proportional pressure reducing valve 5, after the hydraulic pressure input from the input port 73 to the input hydraulic chamber 76 exceeds a certain value determined by the spring 78, the hydraulic pressure of the input port 73, that is, the input hydraulic chamber 76 is proportionally reduced. And output from the output port 72.

The oil passage 71 is connected to the output port 27 of the control brake oil pressure generation means 3 via the switching valve 81. This switching valve 81
Is a cylindrical switching valve body 82 whose both ends are closed, and an oil passage 71.
Valve hole formed in one end wall of the switching valve body 82 while communicating with the
83 and a switching valve body 82 having a valve body 84 capable of closing the valve hole 83 at one end and the other end facing the pilot chamber 85.
A switching piston 86 slidably fitted to the switching valve body, and a switching valve body for biasing the switching piston 86 toward the pilot chamber 85 side.
82 and a spring 87 interposed between the switching piston 86.

A valve chamber 88 communicable with the valve hole 83 is defined between one end wall of the switching valve main body 82 and the switching piston 86, and a spring is formed in the valve chamber 88.
87 is stored. Further, the switching valve body 82 communicates with the valve chamber 88, and the output port 27 of the control brake hydraulic pressure generation means 3 is connected.
An inlet port 89 is provided that communicates with the.

According to the switching valve 81, when the oil pressure in the pilot chamber 85 is lower than a certain value, the switching piston 86 moves to the pilot chamber 85 side to the position where the valve body 84 opens the valve hole 83, and is opened. When the oil pressure in the pilot chamber 85 becomes equal to or higher than the predetermined value, the switching piston 86 moves so as to close the valve hole 83 with the valve body 84 and closes the valve. Therefore, by controlling the hydraulic pressure in the pilot chamber 85, it is possible to switch between communication and cutoff between the output port 27 of the control brake hydraulic pressure generating means 3 and the oil passage 71.

The traction control inflow valve 9 is a solenoid valve that is in a communication state when excited, and is provided between the pilot chamber 85 and the hydraulic pressure supply source 2. The traction control outflow valve 10 is an electromagnetic valve that is turned off when excited, and is provided between the pilot chamber 85 and the reservoir R. Therefore, in the state where the traction control inflow valve 9 and the traction control outflow valve 10 are demagnetized, the switching valve 81 is set in the pilot chamber.
Since the hydraulic pressure of 85 is low, the valve is opened, and when the traction control inflow valve 9 and the traction control outflow valve 10 are excited, the switching valve 81 causes the pilot chamber 85 to receive high hydraulic pressure from the hydraulic pressure supply source 2. The valve is closed accordingly.

The traction control inflow valve 9 and the traction control outflow valve 10 are connected to the oil passage 71 via a one-way valve 90 that bypasses the switching valve 81. The one-way valve 90 allows the working oil to flow toward the oil passage 71 side.
In the energized state of the traction control inflow valve 9 and the traction control outflow valve 10, the hydraulic pressure supply source 2 communicates with the oil passage 71.

The first output port 38 of the hydraulic generating unit 6 is connected to the right front wheel brake device B _FR and the left rear wheel brake device B _RL via an on-off valve 91 _1, the second output port 39 is an opening and closing valve 91 ₂ It is connected to the left front wheel braking device B _FL and the right rear wheel braking device B _RR via Both on-off valve 91 _1, 91 ₂ are those having the same configuration will be described below only the configuration of one of the opening and closing valve 91 _1.

Off valve 91 ₁ is cylindrical on-off valve which both ends are closed body 9
2 and a pair of valve holes 93 drilled in one end wall of the on-off valve body 92
An opening / closing piston 96 having a valve body 94 at one end capable of closing the valve hole 93 at one end and slidably fitted to the opening / closing valve main body 92 with the other end facing the pilot chamber 95; An opening / closing valve body 92 and a spring 97 interposed between the opening / closing piston 96 to urge the operating piston 96 toward the pilot chamber 95 are provided.

A valve chamber 98 that can communicate with the valve hole 93 is defined between one end wall of the on-off valve main body 92 and the on-off piston 96, and a spring is formed in the valve chamber 98.
97 is stored. An opening / closing valve main body 92 is provided with an inlet port 99 communicating with the valve chamber 98 and communicating with the first output port 38.

According to the opening and closing valve 91 _1, and opening and closing piston 96 when the oil pressure in the pilot chamber 95 is lower than the predetermined value to a position where the valve body 94 opens the valve hole 93 is opened by moving the pilot chamber 95 side When the oil pressure in the pilot chamber 95 becomes equal to or higher than the predetermined value, the opening / closing piston 96 moves so as to close the valve hole 93 with the valve element 94 and closes the valve.

Moreover, one valve hole 93 communicates with the output chamber 64 of the one-way hydraulic pressure transmission means 4 _FR , and the other valve hole 93 communicates with the output chamber 64 of the one-way hydraulic pressure transmission means 4 _RL. Device B _FR ,
It is in communication with the braking hydraulic chamber 70 of the B _RL . The pilot chamber 95 communicates with the oil passage 71. Therefore, when the oil pressure in the oil passage 71, that is, the pilot chamber 95 is high, the on-off valve 91 ₁
Is closed and the first output port 38 and brake device B _FR , B
_{When the RL} is cut off and the oil pressure in the oil passage 71 becomes low, the on-off valve 91 ₁
Opens to open the first output port 38 and the brake device B _FR , B
_{Communication is established} between _RL .

The opening and closing valve 91 ₂ is closed by the hydraulic high state of the oil passage 71, whereby the first output port 38 and the brake device B
_When the oil pressure between the _FL and B _RR is shut off and the oil pressure in the oil passage 71 drops, the on-off valve
91 ₂ opens and the 1st output port 38 and brake device
B _FL and B _RR are connected.

First output port 38 of hydraulic pressure generating means 6 and open / close valve 91 ₁
Between the input ports 99, the second output port 39 of the hydraulic pressure generating means 6
And between the opening and closing valve 91 ₂ of the input port 99, as well as between the inlet port 89 of the control brake hydraulic pressure generating means 3 output ports 27 and the switching valve 81, the stroke accumulator 101 is connected. The stroke accumulator 101 includes an accumulator body 102 that is basically cylindrical and has both ends closed, and a first pressure accumulation chamber 103 that communicates with a first output port 38.
The accumulator body 102 is provided with the second pressure accumulation chamber 104 communicating with the second output port 39 and the back pressure chamber 105 communicating with the output port 27.
An accumulator piston 106 slidably fitted to the accumulator body 102 while being defined between
And the volume of the second pressure accumulating chambers 103 and 104 is contracted and the back pressure chamber 105
And a reaction force spring 107 interposed between the stroke accumulator body 102 and the accumulator piston 106 to urge the accumulator piston 106 in the direction of increasing the volume of the accumulator piston 106.

In the accumulator body 102, a first sliding hole 108, a second sliding hole 109, and a third sliding hole 110 are provided coaxially with each other in order from one end in the axial direction toward the other end.
The inner diameters of the sliding holes 108 to 110 are set such that the inner diameter of the second sliding hole 109> the inner diameter of the first sliding hole 108> the inner diameter of the third sliding hole 110. On the other hand, the accumulator piston 106
A middle diameter portion 106a slidably fitted in the first sliding hole 108,
A large diameter portion 106b slidably fitted in the second sliding hole 109;
The small-diameter portion 106c slidably fitted in the third sliding hole 110 is coaxially provided in this order. Thus, the first pressure accumulation chamber 103 is formed by the end wall of the first sliding hole 108 and the middle diameter portion 106a.
The second pressure accumulation chamber 104 is defined between the first and second
The step portion between the sliding holes 108 and 109 and the step portion between the middle diameter portion 106a and the large diameter portion 106b are annularly defined.
It is defined between the end wall of the sliding hole 110 and the end face of the small diameter portion 106c. A spring chamber 111 open to the atmosphere is defined between a step between the second and third sliding holes 109 and 110 and a step between the large diameter portion 106b and the small diameter portion 106c. Is stored in the spring chamber 111. Moreover, the reaction force spring 107 is set so that its spring constant increases as the load increases.

Next, the operation of this embodiment will be described. First, assuming a normal braking operation in a state where the hydraulic supply source 2 is operating normally, the inflow valves 7 _FL , 7 _FR , 7 _R and the outflow valves 8 _FL , 8 _FR ,
8 _R is in the demagnetized state (state shown), and the traction control inflow valve 9 and the traction control outflow valve 10 are also in the demagnetized state (state shown). Therefore, the switching valve 81 is opened, and the output port of the control brake hydraulic pressure generation means 3 is output.
27 communicates with the oil passage 71, which is in communication with the input chamber 63 of the one-way hydraulic pressure transmission means 4 _FL , 4 _FR via the inflow valves 7 _FL , 7 _FR and the inflow valve 7 _R And is connected to the input chamber 63 of the one-way hydraulic pressure transmission means 4 _RL , 4 _RR via the proportional pressure reducing valve 5.

When the brake pedal 1 is depressed in such a state, the hydraulic pressure from the hydraulic pressure supply source 2 is controlled by the control brake hydraulic pressure generation means 3 in accordance with the amount of depression operation, and the controlled hydraulic pressure is output from the output port 27, and the stroke Accumulator 10
It acts on the back pressure chamber 105 and the oil passage 71. Thus hydraulic pressure is unidirectional hydraulic transmission means 4 _FL from the output port 27, 4 _FR is boosted by the brake device B _FL, with given B _FR, decompressed by the proportional pressure reducing valve 5 the hydraulic pressure further unidirectional hydraulic Brake device B boosted by transmission means 4 _RL , 4 _RR
RL and B _RR .

In this way, the braking hydraulic pressure increased by the one-way hydraulic transmission means 4 _FL , 4 _FR , 4 _RL , 4 _RR corresponding to each braking device B _FL , B _FR , B _RL , B _RR is applied. Even if the output hydraulic pressure of the hydraulic pressure supply source 2 is set to be relatively low, it is possible to obtain a sufficient braking pressure in each of the brake devices B _{FL to} B _RR . Therefore, the load of the hydraulic pressure supply source 2 is reduced, and the hydraulic pressure supply source 2 is downsized,
That is, the hydraulic pump 11, the accumulator 12 and the like can be downsized. One-way hydraulic transmission means 4 _FL , 4 _FR , 4 _RL , 4 _RR
Now, with the free piston 65, each brake device B _FL , B _FR ,
Since B _RL and B _RR are isolated from the hydraulic circuit from the input chamber 63 to the hydraulic pressure supply source 2, gas that may be mixed in the hydraulic oil at the hydraulic pressure supply source 2 is applied to each brake device B _FL and B _FR. , B _RL , B _RR are not adversely affected.

During this braking, the braking force of the left and right rear wheels needs to be lower than that of the left and right front wheels, and the hydraulic pressure from the control brake hydraulic pressure generation means 3 is reduced by the proportional pressure reducing valve 5, so that the braking force of the left and right rear wheels is reduced. It is lower than the front wheels at a constant rate.

By the way, the braking hydraulic pressure is also output from the first and second output ports 38, 39 of the hydraulic pressure generating means 6 by driving the first and second working pistons 44, 46 in response to the depression operation of the brake pedal 1. . However, since the hydraulic pressure in the oil passage 71 is high, the on-off valves 91 ₁ , 91 ₂ are closed, and the hydraulic pressures from the first and second output ports 38, 39 are the first and second hydraulic pressures of the stroke accumulator 101. Accumulation chamber 103,1
This will increase the volume of 04, which allows the stroke of the brake pedal 1 to be secured. Moreover, only one stroke accumulator 101 is required for the first and second output ports 38, 39, which can contribute to a reduction in the number of parts.

Further, the reaction force spring 107 of the stroke accumulator 101 is set so that the spring constant increases as the load increases, so the reaction force is increased as the depression amount of the brake pedal 1 increases. The braking operation feeling can be improved. Moreover, since the hydraulic pressure controlled by the control brake hydraulic pressure generating means 3 is introduced into the back pressure chamber 105, the reaction force in the stroke accumulator 101 can be obtained by the reaction force spring 107 and the hydraulic pressure in the back pressure chamber 105. Force spring
The stroke accumulator 101 can be miniaturized to contribute to the miniaturization of the stroke accumulator 101, and the rigidity of the brake pedal 1 can be improved as compared with the case where the reaction force is obtained only by the reaction force spring 107, and the hydraulic pressure supply source is further provided. 2 hydraulic pressure back pressure chamber
The initial braking operation of the brake pedal 1 is smoothed by increasing the hydraulic pressure of the back pressure chamber 105 in accordance with the braking operation, as compared with the case where the reaction force is directly introduced to the 105 or the reaction force is obtained only by the reaction spring 107. In addition, it is possible to improve the operation feeling of the brake pedal 1 by making the stroke reaction force characteristic of the brake pedal 1 excellent.

During such braking, when the pedal force by the brake pedal 1 becomes excessive and the wheels are about to lock, the inflow valves 7 _FL , 7 _FR , and 7 _R corresponding to the wheels that are about to lock are excited to make the oil passage 71 And shut off between one-way hydraulic transmission means 4 _FL to 4 _RR . This suppresses an increase in the braking force to avoid the wheels from being locked. If the wheel is still about to enter the locked state, the corresponding spill valve
By exciting 8 _FL , 8 _FR , 8 _R to _connect the input chamber 63 of the one-way hydraulic pressure transmitting means 4 _FL ~ 4 _RR to the reservoir R and reducing the braking pressure, the wheel locking tendency can be eliminated. .

It is assumed that a high hydraulic pressure cannot be obtained from the hydraulic pressure supply source 2 due to a failure of the hydraulic pump 11 or the like during the braking. In this case, the opening / closing valves 91 ₁ and 91 ₂ are opened according to the decrease in the oil pressure in the oil passage 71 connected to the control brake oil pressure generating means 3. Therefore, the braking oil pressure generated by the oil pressure generating means 6 directly acts on each of the brake devices B _{FL to} B _RR , and the braking force can be secured. At this time, one-way hydraulic pressure transmission means
Since 4 _FL to 4 _RR are provided between the brake devices B _{FL to} B _RR and the control brake hydraulic pressure generating means 3, the braking pressure of each brake device B _{FL to} B _RR is on the control brake hydraulic pressure generating means 3 side. I won't run away.

In addition, the right and left rear wheels have a proportional pressure reducing valve 5 during normal braking.
While the braking hydraulic pressure is acting via the braking hydraulic pressure, the braking hydraulic pressure from the hydraulic pressure generating means 6 directly acts when the hydraulic pressure supply source 2 is out of order, so that a sufficient braking force can be secured.

Next, a hydraulic circuit that connects the first output port 38 of the hydraulic pressure generating means 6 to the right front wheel braking device B _FR and the left rear wheel braking device B _RL , and the second output port 39 of the hydraulic pressure generating means 6.
And a brake circuit B _FL for the left front wheel and a brake device B _RR for the right rear wheel have a hydraulic pressure failure in one of the hydraulic circuits. Suppose. In this case, the hydraulic pressure generated by the hydraulic pressure generating means 6 can secure the braking force in one of the brake devices B _FR , B _RL and the brake devices B _FL , B _RR , and at that time, the accumulator piston in the stroke accumulator 101. The movement of 106 can be made smaller than when both hydraulic circuits are normal, and the increase in the stroke of the brake pedal 1 can be suppressed.

During non-braking after braking operation ends, closing valve 91 ₁ by oil pressure in the oil passage 71, 91 ₂ is opened, the one-way hydraulic transmission means 4 _FL
The output chamber 64 at ~ 4 _RR can be connected to the reservoir R via the hydraulic pressure generating means 6. This prevents negative pressure from being generated in the output chamber 64 in response to the movement of the free piston 65 to the input chamber 63 side in the one-way hydraulic transmission means 4 _FL to 4 _RR, and a reservoir is specially provided for that purpose. Is unnecessary.

Furthermore, during non-braking, the driving force of the engine becomes excessive,
When the drive wheels are about to slip excessively, the traction control inflow valve 9 and the traction control outflow valve 10 are excited and the inflow valves 7 _R corresponding to the left and right rear wheels, which are driven wheels, are excited. As a result, the switching valve 81 is closed, and the high hydraulic pressure from the hydraulic pressure supply source 2 causes the one-way hydraulic pressure transmission means 4 _FL , 4 _FR.
This acts on the input chamber 63, and braking force is generated in the braking devices B _FL and B _FR for the left and right front wheels, which are the driving wheels, and the occurrence of excessive slip is avoided. Thereafter, as in the case of anti-lock control described above, the excitation and demagnetization control of the inlet valve 7 _FL, 7 _FR and the outlet valve 8 _FL, 8 _FR, can control the braking force.

In the above embodiment, the free piston is
One-way hydraulic power transmission means 4 _FL , 4 which are slidably fitted with 65
_{Although FR} , 4 _RL , 4 _RR is provided between the control brake oil pressure generating means 3 and each brake device B _FL , B _FR , B _RL , B _RR , as another embodiment of the present invention, the oil pressure supply source 2 side is provided. The control brake hydraulic pressure generating means 3 and each brake device B _FL , B _FR , B using the check valve which allows only the flow of hydraulic oil from
_It may be provided between _RL and B _RR , or between the hydraulic pressure supply source 2 and the control brake hydraulic pressure generating means 3, and may be closed due to a decrease in the output hydraulic pressure of the hydraulic pressure supply source 2 or the output hydraulic pressure of the control brake hydraulic pressure generating means 3. Control brake hydraulic pressure generating means 3 and each brake device using the on-off valve as a one-way hydraulic pressure transmitting means.
B _FL , B _FR , B _RL , B _RR may be provided respectively, and when the output hydraulic pressure of the hydraulic pressure supply source 2 or the control brake hydraulic pressure generating means 3 is high, the control brake hydraulic pressure generating means 3 and each brake device. B _FL , B _FR , B _RL , B _RR connection state,
When the output hydraulic pressure of the hydraulic pressure supply source 2 or the control brake hydraulic pressure generating means 3 is low, the control brake hydraulic pressure generating means 3 and each of the brake devices B _FL , B _FR , B _RL and B _RR can be switched to a shut-off state. It is also possible to use the above-mentioned switching valve that also has the functions of the on-off valve and the one-way hydraulic pressure transmission means.

C. Effects of the Invention As described above, according to the present invention, since the output port of the control brake hydraulic pressure generation means is connected to the back pressure chamber of the stroke accumulator, the urging force in the direction of contracting the pressure accumulation chamber in the stroke accumulator is applied. , The spring force of the reaction force spring and the force of the hydraulic pressure acting on the back pressure chamber can be combined to reduce the size of the reaction force spring, thereby reducing the size of the stroke accumulator, and braking operation as part of the urging force. By using the output hydraulic pressure of the control brake hydraulic pressure generation means according to the above, the stroke reaction force characteristic of the brake pedal can be improved and the operation feeling can be improved.

[Brief description of the drawings]

The drawing is a hydraulic circuit diagram showing one embodiment of the present invention. 1 ... Brake pedal, 3 ... control brake hydraulic pressure generating means, 6 ... hydraulic pressure generating means, 27 ... output port, 40 ... housing, 43,45 ... hydraulic chamber, 44,46 ... operating piston,
101 …… Stroke accumulator, 103,104 …… Accumulator, 105 …… Back pressure chamber, 107 …… Reaction spring, B _FL , B _FR , B _RL , B _RR …… Brake device

Front Page Continuation (72) Inventor Kazutoshi Tajima 1-4-1 Chuo, Wako-shi, Saitama Inside Honda R & D Co., Ltd. (56) Reference JP 62-26155 (JP, A) JP 57- 84254 (JP, A) JP-A-54-133271 (JP, A) JP-A-2-193755 (JP, A) US Patent 4449369 (US, A)

Claims (1)

(57) [Claims] 1. A control having an output port (27) for outputting a hydraulic pressure according to a braking operation amount, and the output port (27) being connected to a brake device (B _FL , B _FR , B _RL , B _RR ). Brake hydraulic pressure generating means (3); an operating piston (44, 46) interlockingly linked to the brake pedal (1) so as to move forward in response to a braking operation, is slidably fitted in the housing (40),
A hydraulic chamber (43, 45) is formed in the housing (40) so that the front end face of the operating piston (44, 46) is exposed to contract the volume in accordance with the forward movement of the operating piston (44, 46). The hydraulic pressure generating means (6) and the pressure accumulating chambers (103, 104) communicating with the hydraulic pressure chambers (43, 45) of the hydraulic pressure generating means (6) and the urging force in the direction of contracting the volume of the pressure accumulating chambers (103, 104). In a braking hydraulic control device including a stroke accumulator (101) having a reaction force spring (107); and a back pressure chamber (105) of the stroke accumulator (101), an output port (27) of a control brake hydraulic pressure generating means (3). ) Is connected.