JP2552092Y2 - Hydraulic pressure control device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a piston body which is slidably fitted to a cylinder body with its front face facing a pressure chamber, and which has an output port. The valve housing is provided with a spool that receives the hydraulic pressure of the reaction force chamber communicating with the output port in the retreating direction and is spring-biased in the retreating direction. A pressing member, which is slidably fitted and slidably fitted to allow movement between a forward position where a hydraulic pressure supply source for outputting an output hydraulic pressure communicates with the output port, and is interlocked with and coupled to the piston, is a rear end of the spool. The present invention relates to a hydraulic pressure control device to be brought into contact with the hydraulic pressure control device.

[0002]

2. Description of the Related Art Conventionally, such a hydraulic control device is known from, for example, Japanese Patent Application Laid-Open No. Hei 4-274955.

[0003]

In this hydraulic control device, the piston moves forward from the retreat limit position in response to the operation of the operating member, and the spool is pushed to the forward position by the advance operation of the pressing member in accordance with the operation. However, the initial interval between the pressing member and the spool is not constant due to a manufacturing error and an assembling error of each component part, and the time when the pressing member starts to press the spool, that is, the time when the hydraulic pressure control is started, is reduced. May shift. Therefore, in order to eliminate such a deviation, it is necessary to perform an initial adjustment of an initial interval between the pressing member and the spool at the time of assembling. However, in the above-described conventional apparatus, the initial adjustment is complicated.

The present invention has been made in view of such circumstances, and an object of the invention is to provide a hydraulic pressure control device capable of easily performing initial adjustment of an interval between a pressing member and a spool.

[0005]

According to the present invention, in order to achieve the above object, according to the present invention, the pressing member is interlocked with and connected to the piston with the maximum distance between the pressing member and the piston being restricted. And a cylindrical small cylinder body fitted and fixed to the cylinder body with axial position adjusting means interposed between the cylinder body and the cylinder body, and the spool has a retreat limit position with respect to the small cylinder body. It is regulated and slidably fitted to the small cylinder body.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a brake pressure control device for a front wheel drive vehicle will be described below with reference to the drawings.

FIGS. 1 to 7 show an embodiment of the present invention. FIG. 1 is a hydraulic circuit diagram of a brake pressure control device.
2 is a longitudinal sectional view showing the configuration of the hydraulic pressure transmission unit, FIG. 3 is a longitudinal sectional view showing the configuration of the flow control unit, FIG. 4 is a longitudinal sectional view showing a partial configuration of the control hydraulic pressure output unit, and FIG. FIG. 6 is a vertical sectional view showing the configuration of the stroke accumulator, and FIG. 7 is a diagram showing the relationship between the input piston stroke and the spring reaction force in the auxiliary hydraulic pressure generating means. It is.

First, in FIG. 1, a left front wheel brake device _BFL and a right front wheel brake device _BFR are mounted on a left front wheel and a right front wheel as driving wheels of a vehicle, respectively. The left rear wheel brake device _BRL and the right rear wheel brake device _BRR are mounted on the rear wheels. On the other hand, the brake pedal 1 as an operating member can control the output hydraulic pressure of the hydraulic pressure supply source 3 according to the amount of depression of the brake pedal 1 and, when the output pressure of the hydraulic pressure supply source 3 is abnormally low, the brake pedal 1 is connected to a control hydraulic pressure output unit 2 capable of outputting a hydraulic pressure in accordance with the amount of depression, and outputs from the control hydraulic pressure output unit 2 during normal braking when the output hydraulic pressure of the hydraulic pressure supply source 3 is normal. The amplified hydraulic pressure is supplied to the front wheel brake devices B _FL and B _FR via the hydraulic pressure transmission units 4 _FL and 4 _FR, and the amplified hydraulic pressure from the control hydraulic pressure output unit 2 is applied to the hydraulic pressure transmission unit 4 FL. _R
And via a proportional pressure reducing valve 5 to both rear wheel brake devices B _RL , B _RR . When the output hydraulic pressure of the hydraulic pressure supply source 3 drops abnormally, the non-amplified hydraulic pressure output from the control hydraulic pressure output unit 2 corresponding to the amount of depression of the brake pedal 1 changes to the hydraulic pressure transmission units 4 _FL and 4 _FR. , And the non-amplified hydraulic pressure from the control hydraulic pressure output unit 2 is applied to both front wheel brake devices B _FL and B _FR via a hydraulic pressure transmission unit 4 _R and a proportional pressure reducing valve 5. It is provided to the brake devices B _RL and B _RR . Furthermore brake device B _FL for the front wheels, inlet valve 6 _FL individually corresponding to B _FR, 6 _FR and the outlet valve 7 _FL, 7 _FR and the rear wheels brake device B _RL, which is common to B _RR inlet valve 6 _The normally open solenoid valve for traction control can hold or reduce the brake fluid pressure of each of the brake devices B _FL , B _FR , B _RL , and B _RR by using the _R and the outflow valve 7 _R to perform antilock control. By controlling the opening and closing of the solenoid valve 8 and the normally closed solenoid valve 9, traction control can be performed by increasing the brake fluid pressure of both front wheel brake devices B _FL and B _FR .

The hydraulic pressure supply source 3 includes a hydraulic pump 10 for pumping hydraulic fluid from a reservoir R, an accumulator 11 connected to the hydraulic pump 10, and a pressure switch for controlling the operation of the hydraulic pump 10. 12 is provided.

The hydraulic pressure transmission units 4 _FL , 4 _FR , and 4 _R have basically the same configuration, and the configuration of the hydraulic pressure transmission unit 4 _FL will be described below as a representative.

In FIG. 2, the hydraulic pressure transmission unit 4 _FL is
A housing 18 formed in a cylindrical shape with both ends closed, a free piston 21 slidably fitted in the housing 18 with both ends facing the input hydraulic chamber 19 and the output hydraulic chamber 20, Between the spring 22 housed in the output hydraulic chamber 20 to urge the hydraulic pump 21 toward the input hydraulic chamber 19 and the passage 24 and the output hydraulic chamber 20 when the output hydraulic pressure of the hydraulic pressure supply source 3 is normal. And a bypass valve 23 provided in the housing 18 so as to communicate between the passage 24 and the output hydraulic pressure chamber 20 when the output hydraulic pressure of the hydraulic pressure supply source 3 is abnormally lowered.

The output hydraulic chamber 20 communicates with the brake device _BFL via a passage 25. On the outer periphery of the free piston 21, there is provided an annular recess which forms an annular chamber 26 between the inner surface of the housing 18 and the outer periphery of the free piston 21 between the annular chamber 26 and the input hydraulic chamber 19. A seal member 27 is provided on the outer periphery of the free piston 21 between the annular chamber 26 and the output hydraulic chamber 20.
Are respectively mounted. Thus, at least the seal member 28 is a cup seal, and allows the hydraulic fluid to flow from the annular chamber 26 to the output hydraulic chamber 20. In addition, a communication hole 29 communicating with the annular chamber 26 is provided in the housing 18 regardless of the stroke of the free piston 21.
9 is connected to the reservoir R via the release passage 40, and the annular chamber 26 is always in communication with the reservoir R.

The output hydraulic pressure chamber 20 is formed in a cylindrical shape between the bypass valve 23 and the free piston 21.
And a valve housing 31 fitted and fixed in the housing 18, and a valve hole 31 communicating with the output hydraulic pressure chamber 20, which is opened at the center to form a valve housing 30 near the output hydraulic pressure chamber 20. A valve seat 32 provided and a valve chamber 33 communicating with the passage 24 are defined between the valve seat 32 and an end opposite to the valve chamber 33 faces the pilot chamber 34 so that the inside of the valve housing 30 is opened. A drive piston 35 slidably fitted in the valve seat 32, a spherical valve body 36 housed in the valve chamber 33 so as to be seated on the valve seat 32 and fixed to the tip of the drive piston 35, And the valve body 36 is accommodated in a spring chamber 37 formed between the valve housing 30 and the valve body 36 generates a repulsive force in the direction away from the valve seat 32 by the drive piston 35.
, A passage 44 communicates with the pilot chamber 34, and the spring chamber 37 communicates with the reservoir R via a release passage 40.

In the bypass valve 23, when the hydraulic pressure in the pilot chamber 34 is lower than a predetermined value, the spring 38
The drive piston 35 moves to a position where the valve element 36 opens the valve hole 31 by the spring force of
When the hydraulic pressure in the pilot chamber 34 becomes equal to or higher than the predetermined value, the drive piston 35 moves so as to close the valve hole 31 with the valve body 36 and is closed.

According to such a configuration of the liquid pressure transmission unit 4 _FL, input hydraulic pressure chamber in a state where the bypass valve 23 is closed 19
Can be output from the output hydraulic chamber 20, and the hydraulic fluid in the output hydraulic chamber 20 does not flow to the input hydraulic chamber 19 side. Also, the bypass valve 23
Is open, the hydraulic pressure from the passage 24 can be guided to the output hydraulic chamber 20 even when the hydraulic pressure is not acting on the input hydraulic chamber 19.

Furthermore the liquid pressure transmission unit 4 _FL, 4 _FR of the output fluid pressure chamber 20 is communicated each communicating separately to the brake device B _FL, B _FR, the output hydraulic pressure chamber 20 of the liquid pressure transmission unit 4 _R is proportional common The brake devices B _RL and B _RR are connected via the pressure reducing valve 5.

The front wheel brake device B _FL, the input hydraulic pressure chamber 19 of the liquid pressure transmission unit 4 _FL, 4 _FR corresponding to B _FR, inlet valve 6 _FL, 6 _FR and the outlet valve 7 _FL, 7 _FR parallel To the input hydraulic chamber 19 of the hydraulic transmission unit 4 _R corresponding to the rear wheel brake devices B _RL , B _RR.
R and outlet valve 7 _R are connected in parallel.

The inlet valve 6 _FL, 6 _FR, 6 _R is a normally open solenoid valve which closes when energized, outlet valve 7 _FL, 7 _FR, 7 _R is a normally closed electromagnetic valve which opens when energized . Thus, the outflow valve 7 _FL ,
7 _FR, 7 _R of the input liquid pressure chamber 19 of the liquid pressure transmission unit _{4 FL, 4 FR, 4 R} , are respectively interposed between the relief passageway 40 leading to the reservoir R. The inlet valves 6 _FL and 6 _FR are connected to the input hydraulic chamber 19 and the passage 41 of the hydraulic pressure transmission units 4 _FL and 4 _FR.
Respectively interposed between the inlet valve 6 _R is interposed between the input fluid pressure chamber 19 and the passage 42 of the liquid pressure transmission unit 4 _R as shown in Figure 1.

The proportional pressure reducing valve 5, which has a well-known structure, the liquid pressure transmission unit 4 _R proportionally reduced pressure to both rear wheel brake device hydraulic pressure output from the output fluid pressure chamber 20 of the It functions to act on B _RL and B _RR .

The normally open solenoid valve 8 for traction control includes:
It is provided between the passages 43 and 44, and is switchable between a state in which the passages 43 and 44 communicate with each other in a demagnetized state and a state in which the passages 43 and 44 are shut off in an excited state. The normally closed solenoid valve 9 for traction control includes a hydraulic pressure source 3
Between the fluid pressure supply source 3 and the passage 44 in a demagnetized state, and between the fluid pressure supply source 3 and the passage 4 in an excited state.
It is possible to switch between the four states. Thus, during traction control, both solenoid valves 8 and 9 are excited.

A one-way valve 45 which allows only the flow of the hydraulic fluid from the passage 43 to the passage 44 is connected in parallel with the normally-open solenoid valve 8, and this one-way valve 45 is connected to the brake pedal during traction control. 1 functions to guide the hydraulic pressure output from the control hydraulic pressure output unit 2 to the passage 43 when the brake operation is performed.

Further, the passage of the hydraulic fluid from the passage 44 to the passage 41 is permitted between the passages 44 and 41 as the fluid pressure on the passage 44 side becomes larger than the fluid pressure on the passage 41 by a predetermined value or more. The differential pressure valve 46 functions as a one-way valve that allows the hydraulic fluid to flow from the passage 41 to the passage 44 as the hydraulic pressure in the passage 41 becomes slightly higher than the hydraulic pressure in the passage 44. A flow restricting unit 48 including a cup seal 47 is provided.

In FIG. 3, the distribution control unit 48
Cylindrical housing 5 with one end closed by a closing member 49
In the housing 50, a liquid chamber 51 communicating with the passage 44 is formed between the closing member 49 and the valve housing 52 fitted in the housing 50.
Is provided, and a cup seal 47 that slides on the inner surface of the housing 50 is mounted on the outer periphery of the valve housing 52. Also, the valve housing 52 and the closing member 49
A spring 53 for urging the valve housing 52 toward the other end of the housing 50 is contracted between them.

A differential pressure valve 46 is provided in the valve housing 52 with a valve hole 55 communicating with the liquid chamber 51 opened at the center in a valve chamber 54 formed in the valve housing 52 through the passage 41. A valve body 57 which can be seated on the valve body 56;
5 which exerts a resilient force in a direction in which the valve seat 56 is seated on the valve seat 56.
And is opened when the fluid pressure of the fluid chamber 51 communicating with the passage 44 becomes higher than the fluid pressure of the valve chamber 54 communicating with the passage 41 by a predetermined value or more. .

The cup seal 47 prevents the hydraulic fluid from flowing from the liquid chamber 51 to the passage 41. However, when the hydraulic pressure in the passage 41 becomes larger than the hydraulic pressure in the liquid chamber 51,
It is mounted on the outer periphery of the valve housing 52 so as to allow the hydraulic fluid to flow from the fluid chamber 51 to the fluid chamber 51.

[0026] According to the differential pressure valve 46, the braking operation early, hydraulic until the liquid pressure transmission unit 4 _FL, 4 _FR, 4 bypass valve 23 in _R is closed in response to fluid pressure increase in the pilot chamber 34 The hydraulic fluid from the passage 44 to the passage 41 communicating with the input hydraulic chamber 19 of the transmission units 4 _FL and 4 _FR is blocked. That is, in the initial stage of the braking operation, the braking pressure acts on the input hydraulic chamber 19 of the hydraulic pressure transmission units 4 _FL and 4 _FR after each bypass valve 23 is closed. When the braking operation force is released, the hydraulic fluid in the passage 41 is released to the reservoir R by the cup seal 47.

In FIGS. 4 and 5, the control hydraulic pressure output unit 2 includes an auxiliary hydraulic pressure generating means 61 capable of generating a non-amplified hydraulic pressure corresponding to the braking operation force of the brake pedal 1,
A hydraulic pressure control valve 62 capable of controlling the output pressure of the hydraulic pressure supply source 3 in accordance with the operation amount of the brake pedal 1 and outputting the amplified hydraulic pressure.

The control hydraulic pressure output unit 2 includes a cylinder body 64 formed in a cylindrical shape. Inside the cylinder body 64, a cylinder hole 66 and a cylinder hole 66 having a diameter larger than the cylinder hole 66 are formed. Fitting hole 67 coaxially connected to the front end
And a screw hole 68 having a diameter larger than that of the fitting hole 67 and coaxially connected to a front end of the fitting hole 67.

The valve housing 63 of the hydraulic pressure control valve 62
The small cylinder body 65 is fitted and fixed in the front end of the cylinder body 64. The small cylinder body 65 is engaged with a stepped portion 69 between the cylinder hole 66 and the fitting hole 67 via a spacer 60 as an axial position adjusting means.
5a at the front end and is formed in a cylindrical shape.
Is fitted to. In addition, the plug member 70 is fitted into the fitting hole 67, and the screw member 71 screwed into the screw hole 68 is tightened.
The small cylinder body 65 is fixed in the cylinder body 64 by the nipping and the engagement flange 65a. The small cylinder body 65 is provided with a small sliding hole 72 and a large sliding hole 73 coaxially connected to the rear end of the small sliding hole 72.

The hydraulic pressure control valve 62 has a spool 74 slidably fitted in a small sliding hole 72 of a small cylinder body 65. A reaction force chamber 75 facing the front surface of the spool 74 is defined between the small cylinder body 65 and the plug member 70, and the reaction force chamber 75 communicates with the passage 42. At the front end of the spool 74, a retaining ring 76 that abuts against the small cylinder body 65 and regulates the retreat limit of the spool 74 is fitted. A spring 77 for urging the spool 74 rearward is contracted.

In the large sliding hole 73 of the small cylinder body 65, a pressing piston 78 as a pressing member, which is one element of the auxiliary hydraulic pressure generating means 61, is slidably fitted. Reference numeral 78 contacts the rear end of the spool 74. Further, a release chamber 79 defined between the pressing piston 78 and the small cylinder body 65 is communicated with the reservoir R. Accordingly, a force toward the rear side acts on the spool 74 by the hydraulic pressure of the reaction force chamber 75 and the spring 77, and a force toward the front side by the pressing piston 78 acts. The position of the spool 74 in the small cylinder body 65 is determined by the balance.

The cylinder body 64 and the small cylinder body 65 which cooperate to form the valve housing 63 are provided with small sliding holes 72 at intervals in order from the front side to the rear side in the axial direction.
An input port 80, an output port 81, and a release port 82 which are open on the inner surface are provided. The input port 80 is connected to a passage 83 leading to the hydraulic pressure supply source 3, and is also connected to a normally closed solenoid valve 9 via a passage 39. Connected to the output port 8
1 is connected to the passage 43, and the release port 82 is connected to the release passage 4.
It is communicated to the reservoir R via 0. And spool 7
An annular recess 84 is provided on the outer periphery of the spool 4. The length of the annular recess 84 along the axis of the spool 74 is
When the spool 4 is in the forward position, the output port 81 communicates with the input port 80 via the annular recess 84 and is cut off from the release port 82. When the spool 74 is in the retracted position, the output port 81 communicates through the annular recess 84. It is set so as to communicate with the release port 82 and to cut off from the input port 80.

The passage 4 leading to the output port 81
Between the passage 43 and the reaction chamber 75, the passage 43, that is, the fluid pressure on the output port 81 side becomes larger than the fluid pressure on the reaction chamber 75 side by a predetermined value or more from the passage 43 to the reaction chamber 75. A differential pressure valve 85 that allows the hydraulic fluid to flow through, and the hydraulic fluid flows from the reaction chamber 75 to the passage 43 in response to the hydraulic pressure on the reaction chamber 75 becoming slightly higher than the hydraulic pressure on the passage 43 side. A cup seal 86 that functions as a one-way valve that permits flow is provided.

The cylinder body 64 in the valve housing 63
Is provided with an introduction port 88 communicating with the passage 43. A differential pressure valve 85 is connected between the introduction port 88 and the reaction force chamber 75 to open and close a passage 89 provided in the plug member 70.
The differential pressure valve 85 is provided with a valve seat 90 that opens to a reaction chamber 75 through a passage 89, and a valve that can be seated on the valve seat 90 and is housed in the reaction chamber 75. Body 91
And a spring 92 for urging the valve element 91 in a direction of sitting on the valve seat 90. The cup seal 86 is provided in the reaction force chamber 7.
5 is attached to the outer periphery of the plug member 70 while allowing the hydraulic fluid to flow from the inlet port 88.

According to the differential pressure valve 85, the output port 81 of the control hydraulic pressure output unit 2 is connected to the passage 43 at the beginning of the braking operation.
The hydraulic pressure is not generated in the reaction force chamber 75 until the hydraulic pressure output to the pressure reaches a certain value, so that the hydraulic pressure output to the passage 43 before the operation reaction force is generated in the initial stage of the braking operation is reduced to a certain value. and it not only works to increase up to a value, until closing the liquid pressure transmission unit 4 _R of the bypass valve 23 is intended to suppress the hydraulic output of the passage 42 leading to the input hydraulic pressure chamber 19 in the liquid pressure transmission unit 4 _R. Thus the braking operation early, after the bypass valve 23 of the liquid pressure transmission unit 4 _R is closed, fluid pressure in the passage 42 acts on the input hydraulic pressure chamber 19 of the liquid pressure transmission unit 4 _R. Further, the cup seal 86 allows the hydraulic fluid in the passage 42 to pass through the passage 43 when the braking operation force is released.
To output port 81, annular recess 84 and release port 8
It functions to escape to the reservoir R through 2.

The auxiliary hydraulic pressure generating means 61 includes a hydraulic control valve 62
Between the pressing piston 78, which is interlocked and connected to the rear end of the spool 74, and is slidably fitted in the large sliding hole 73, and the rear surface of the pressing piston 78 which is interlocked and connected to the brake pedal 1 An input piston 94 slidably fitted in the cylinder hole 66 with the front face facing the defined pressure chamber 93, and a pair of springs 95, 96 interposed in series between the pistons 78, 94. Is provided.

A restricting member 97 for restricting the retraction limit of the input piston 94 is fixed to the rear end opening of the cylinder body 64, and a piston rod 98 which movably penetrates the restricting member 97 in a fluid-tight manner is input. The piston 94 is coaxially connected. On the other hand, a push rod 99 is connected to the brake pedal 1, and the front end of the push rod 99 is swingably connected to the piston rod 98. Therefore, the input piston 94 moves forward in the direction of reducing the volume of the pressure chamber 93 in response to the depression operation of the brake pedal 1.

A cup-shaped retainer 100 is fitted into the front end of the input piston 94, and a cylindrical retainer 101 with a bottom is in contact with the back surface of the pressing piston 78. A retainer 101 is provided between the retainers 100 and 101. A spring 95 having a guide member 102 slidably fitted to the spring 95 interposed therebetween.
96 is contracted. In addition, the rear end of the rod 103 movably penetrating the retainer 101 is engaged with the retainer 100 such that the retreat limit position with respect to the pressing piston 78 is regulated by the retainer 101. This regulates the maximum distance between the pressing piston 78 and the input piston 94. The spring 95 has a relatively large spring constant,
Are set relatively small.

A valve hole 104 provided in the input piston 94 through the reservoir R, a valve body 105 provided at the rear end of the rod 103, and a rod 103 biasing the rod 103 in a direction in which the valve body 105 closes the valve hole 104. A shut-off valve 107 for switching between communication and shut-off between the pressure chamber 93 and the reservoir R is constituted by the spring 103 provided between the rod 103 and the retainer 100, and the shut-off valve 107 is provided with a pressing piston 78 and an input. When the interval between the pistons 94 is maximum, the valve is opened to connect the pressure chamber 93 to the reservoir R. When the input piston 94 moves forward with respect to the rod 103 from this state, the valve closes to open the pressure chamber. Shut off between 93 and reservoir R.

In such a control hydraulic pressure output unit 2, the pressure receiving area A ₁ of the spool 74 facing the reaction force chamber 75 is:
Smaller than the pressure receiving area A ₂ of the pressure piston 78 facing the pressure chamber 93, also the pressure receiving area A ₃ of the input piston 94 facing the pressure chamber 93 is larger than the pressure receiving area A ₂ of the pressure piston 78. That is, A ₁ <A ₂ <A ₃ .

By the way, in the control hydraulic pressure output unit 2, when the input piston 94 of the auxiliary hydraulic pressure generating means 61 is at the retreat limit position, the pressing piston 78 which has the maximum distance from the input piston 94 is set. It is desirable that the distance between the front end and the rear end of the spool 74 located at the retreat limit position with respect to the small cylinder body 65 is extremely small, so that the hydraulic pressure control valve 62 according to the depression operation of the brake pedal 1 Responsiveness can be improved. However, it is difficult to always minimize the distance between the front end of the pressing piston 78 and the rear end of the spool 74 due to the dimensional error and the assembly error of each component of the control hydraulic pressure output unit 2. It is necessary to adjust the distance at the time of attachment. Thus, the small cylinder body 62 in the hydraulic pressure control valve 62
The axial position in the cylinder body 64 is determined according to the thickness of the spacer 60. A plurality of types of spacers 60 having different thicknesses are prepared in advance, and are appropriately set when the control hydraulic pressure output unit 2 is assembled. By using the spacer 60 having a large thickness, the front end of the pressing piston 78 and the spool 7
The adjustment for minimizing the initial distance between the rear ends of the rear ends can be extremely easily performed.

A passage 108 is connected to the pressure chamber 93 of the auxiliary hydraulic pressure generating means 61, and this passage 108 is connected to a stroke accumulator 113 as shown in FIG.

Referring to FIG. 6, a stroke accumulator 113 includes an accumulator piston 116 formed between a casing 114 and a casing 114 so as to form a pressure accumulating chamber 115 communicating with a passage 108, and a pilot accumulator piston 116. Chamber 117 into casing 114
, Accumulator springs 119 and 120 as first urging means for urging and accumulating the accumulator piston 116 toward the side of reducing the volume of the pressure accumulating chamber 115, and both accumulator springs 11.
A backup spring 121 is provided as second biasing means for resiliently biasing the backup piston 118 on the side where the volume of the pilot chamber 117 is reduced by exerting a spring load greater than the spring load by the springs 9 and 120.

The casing 114 has a first cylinder hole 122 closed at one end, and has a larger diameter than the first cylinder hole 122, and one end is coaxially connected to the other end of the first cylinder hole 122 via a step 124. The second cylinder hole 123 has a diameter larger than that of the second cylinder hole 123 and is larger than the second cylinder hole 12.
An open end of a stepped bottomed cylinder 127 having a third cylinder hole 125 whose one end is coaxially connected via a tapered step 126 to the other end of 3 is closed by a closing member 128.

The accumulator piston 116 forms a pressure accumulating chamber 115 between itself and one end wall of the casing 114, and is slidably fitted in the first cylinder hole 122. The backup piston 118 defines a release chamber 129 communicating with the reservoir R between the backup piston 118 and the accumulator piston 116, and is slidably fitted in the second and third cylinder holes 123 and 125. A pilot chamber 117 is defined between the inner surfaces of 126 and third cylinder hole 125 and the outer surface of backup piston 118. The pilot chamber 117 is communicated with the hydraulic pressure supply source 3 through a passage 112 connected to a port 114 a provided in the casing 114, and is connected to the port 114 b by 18.
The hydraulic pressure control valve 62 is connected via a passage 83 connected to a port 114b provided in the casing 114 at a position shifted by 0 degree.
Is connected to the input port 80. That is, the hydraulic pressure source 3
Is connected to the input port 80 of the hydraulic pressure control valve 62 through the passages 112 and 83 passing through the pilot chamber 117.

The backup piston 118 is formed in a cylindrical shape, and a receiving flange 130 is provided at a front end thereof, that is, at a portion near the accumulator piston 116, to protrude inward in the radial direction.

The accumulator springs 119 and 120 have a retainer 132 and a guide member 131 interposed therebetween.
133 in series. In the middle portion of the piston rod 134 coaxially connected to the accumulator piston 116, a flange portion 13 extending radially outward is provided.
4a is provided, and the retainer 132
It is formed in a disk shape surrounding the piston rod 134 so as to be engaged with a. In addition, the retainer 133 is formed in a bottomed cylindrical shape in which an open end abuts on the closing member 128. Further, the guide member 131 is slidably fitted to the piston rod 134, and the accumulator spring 119 is provided.
Is between the retainer 132 and the guide member 131 engaged with the flange portion 134a of the piston rod 134, and the accumulator spring 120 is provided between the guide member 131 and the closing member 128.
Is provided between the retainer 133 and the retainer 133 which is supported by the above. Therefore, the load characteristics of both accumulator springs 119 and 120 are as follows.
While the accumulator piston 116 moves toward the side where the volume of the accumulator 115 increases, the spring load characteristics for urging the accumulator piston 116 toward the accumulator 115 change so as to be different from each other.

The backup spring 121 is provided in the release chamber 129.
Inside, it is contracted between the receiving flange 130 and the retainer 133 of the backup piston 118.

Such a stroke accumulator 11
3, when the hydraulic pressure supply source 3 is operating normally and the normal hydraulic pressure from the hydraulic pressure supply source 3 is acting on the pilot chamber 117, as shown in FIG. It moves to the side that increases the volume of the pilot chamber 117 against the urging force of the spring 121, that is, the side that is separated from the accumulator piston 116. However, when the operation of the hydraulic pressure supply source 3 becomes abnormal and the hydraulic pressure in the pilot chamber 117 drops abnormally, the backup piston 118 moves to the side of reducing the volume of the pilot chamber 117 by the spring force of the backup spring 121, that is, to the accumulator piston 116. The backup flange 118 of the backup piston 118 is moved to
32. Therefore, accumulator piston 1
A large spring load of the backup spring 121 acts on 16 in addition to the accumulator springs 119 and 120.

In this stroke accumulator 113, accumulator piston 116 and retainer 1
The maximum distance between the retainers 133 and the backup piston 118 is regulated by the engagement of the retainer 133 with the piston rod 134 connected to the accumulator piston 116, and the backup piston 118 is engaged with the accumulator piston 116. It is regulated by doing. That is, the flange 1 of the piston rod 134
The maximum interval between the retainer 133 and the backup piston 118 is regulated by the engagement of the backup piston 118 with the retainer 132 engaged with the retainer 132a.
Therefore, the accumulator piston 116, the retainer 132, the two accumulator springs 119 and 120, the retainer 133, the backup piston 118, and the backup spring 121 can be assembled separately from the casing 114 as an interior assembly. After the insertion into the bottomed cylindrical body 127, the assembly of the stroke accumulator 113 is completed only by attaching the closing member 128 to the bottomed cylindrical body 127, so that the workability of assembling the stroke accumulator 113 is improved.

By the way, the stroke accumulator 11
3, when the hydraulic pressure in the pressure accumulating chamber 115 becomes higher than the hydraulic pressure in the passage 24 by a predetermined value or more,
Differential pressure valve 136 that allows the flow of hydraulic fluid to
The cup seal 137 that functions as a one-way valve that permits the flow of the hydraulic fluid from the passage 24 to the pressure accumulating chamber 115 in accordance with the hydraulic pressure of
And a cup seal 138 that functions as a one-way valve that permits the flow of hydraulic fluid from the release chamber 129 communicating with the reservoir R to the passage 24 when the pressure in the passage 24 is reduced.
Are provided.

An annular recess which forms an annular chamber 139 between the accumulator piston 116 and the inner surface of the first cylinder hole 122 of the casing 114 is provided on the outer periphery of the accumulator piston 116. 1
A connection hole 140 communicating with the connection hole 39 is formed.
Is connected to the passage 24. Therefore, the annular chamber 139 communicates with the passage 24.

The differential pressure valve 136 communicates with the annular chamber 139 and is provided in the valve chamber 141 of the accumulator piston 116.
A valve body 144 having a valve hole 142 communicating with the accumulator chamber 115 is opened at the center, and a valve body 144 facing the inside of the valve chamber 141 and capable of being seated on a valve seat 143 provided in the accumulator piston 116. 143 and a spring 145 which exerts a resilient force in a direction to be seated on are those, which are accommodated, each of the liquid pressure transmission unit 4 _FL, 4 _FR, 4 the valve chamber 33 of the bypass valve 23 in the _R channel 24 and annular Room 13
The valve is opened when the hydraulic pressure of the valve chamber 141 communicating through the pressure valve 9 is lower than the hydraulic pressure of the accumulator chamber 115 by a certain value or more, and the hydraulic pressure of the accumulator chamber 115 is increased by the hydraulic pressure transmission units 4 _FL , 4 _FR , 4 It functions to act on the _R valve chamber 33.

The cup seal 137 is provided in the annular chamber 139.
And an accumulator piston 116
The cup seal 138 is attached to the outer periphery of the annular chamber 13.
9 and the release chamber 129 between the accumulator piston 11
6 is attached to the outer periphery.

According to the differential pressure valve 136, until the hydraulic pressure generated in the pressure chamber 93 of the auxiliary hydraulic pressure generating means 61 in the control hydraulic pressure output unit 2 with the braking operation of the brake pedal 1 reaches a certain value or more. The output pressure of the auxiliary hydraulic pressure generation means 61 is prevented from acting on the valve chamber 33 of the bypass valve 23 in each of the hydraulic pressure transmission units 4 _FL , 4 _FR , 4 _R , and the bypass valve 23 increases the pilot pressure of the pilot chamber 34. , The differential pressure valve 136 can be opened. In addition, breathing of the passage 24 due to advancing of the braking piston or temperature change due to wear of the brake pad in each of the brake devices B _FL , B _FR , B _RL , and B _RR .
37, through a cup seal 138 when the pressure is reduced.

Next, the operation of this embodiment will be described. First, assuming a normal braking operation in a state where the hydraulic pressure supply source 3 is operating normally, the inflow valves 6 _FL , 6 _FR , 6 _R
The outflow valves 7 _FL , 7 _FR , and 7 _R are in a demagnetized state (the state shown in FIG. 1), and a normally-open solenoid valve 8 for traction control.
The normally closed solenoid valve 9 is also in the demagnetized state (the state shown in FIG. 1). Therefore, the output port 8 of the control hydraulic pressure output unit 2
The passage 43 for guiding the amplified hydraulic pressure from the first unit 1 communicates with the pilot chamber 34 of the bypass valve 23 in each of the hydraulic pressure transmission units 4 _FL , 4 _FR , 4 _R via the passage 44, and also via the differential pressure valve 46 and the passage 41. And is connected to the input hydraulic chamber 19 of the hydraulic pressure transmission units 4 _FL and 4 _FR , and the differential pressure valve 8
5, in the connected state to the input fluid pressure chamber 19 of the liquid pressure transmission unit 4 _R through the reaction chamber 75 and the passage 42.

When the brake pedal 1 is depressed in this state,
In the control hydraulic pressure output unit 2, the input piston 94 moves forward to apply a forward force to the pressing piston 78 via the springs 95 and 96, thereby causing the spool 74 of the hydraulic pressure control valve 62 to move forward.
Moves forward while contracting the spring 77.

The spool 74 advances to a position where the input port 80 communicates with the output port 81 and is cut off from the release port 82, and is operated by the differential pressure valve 85 until the output pressure of the passage 43 reaches a certain value. No hydraulic pressure in the power chamber 75, that is, a hydraulic pressure for urging the spool 74 in the backward direction, is generated, and a rapidly increasing hydraulic pressure is output to the passage 43 at the beginning of the braking operation. Thereby, each hydraulic pressure transmission unit 4 _FL ,
Bypass valve 23 is closed at 4 _FR, 4 _R, then with each fluid pressure acting from the passage 41 to the input fluid pressure chamber 19 of the liquid pressure transmission unit 4 _FL, 4 _FR by opening of the differential pressure valve 46, the difference The hydraulic pressure transmission unit 4 _R is opened by opening the pressure valve 85.
The hydraulic pressure acts on the input hydraulic chamber 19 from the passage 42.

In the hydraulic pressure control valve 62, the spring 77
And the force in the retreating direction, which is the sum of the force obtained by multiplying the cross-sectional area of the spool 74 by the hydraulic pressure of the reaction force chamber 75, becomes larger than the spring load of the springs 95, 96.
The input piston 94 moves forward with respect to the pressing piston 78 while reducing the pressure 96, the shutoff valve 107 is closed, the pressure chamber 93 is shut off from the reservoir R, and the volume of the pressure chamber 93 is reduced. A hydraulic pressure is generated in the chamber 93.

Therefore, even though the pressure accumulating chamber 115 of the stroke accumulator 113 for securing the operation stroke is communicated with the pressure chamber 93, the initial operation stroke is absorbed by the stroke accumulator 113 and becomes an invalid stroke. Nor.

Thereafter, the hydraulic pressure in the pressure chamber 93 is accumulated in the accumulator chamber 115 of the stroke accumulator 113, and the input piston 94 is actuated by the operating force opposing the urging force of the accumulator springs 119 and 120 acting on the accumulator piston 116. Is further advanced, and an operation stroke can be secured by the stroke accumulator 113.

After the hydraulic pressure is generated in the pressure chamber 93, the hydraulic pressure control valve 6
2, the spool 74 moves back and forth so that the force in the retreating direction from the reaction force chamber 75 side and the force in the forward direction from the pressure chamber 93 side are balanced, whereby the output pressure of the hydraulic pressure supply source 3 is reduced. The controlled hydraulic pressure output unit 2 outputs an amplified hydraulic pressure to the passage 43 according to the operation amount of the brake pedal 1,
Each of the brake devices B _FL , B _FR , B _RL , and B _RR provides a braking force by the amplified hydraulic pressure. Thus, the hydraulic circuit on the hydraulic pressure supply source 3 side and the respective brake devices B _FL , 4 _FL , 4 _FL , 4 _FR , 4 _{R by} the free piston 21.
B _FR, B _RL, since between the B _RR is isolated, liquid pressure supply source 3 possible gas each brake device to be mixed into operating fluid in the side _{B FL, B FR, B RL} , the B _RR The adverse effects are prevented.

By the way, when the hydraulic pressure is generated in the reaction force chamber 75, the spool 74 is connected to the output port 81 and the input port 80.
When the input piston 94 is further advanced by further operating the brake pedal 1 in a state where the distance is shut off,
Is smaller than the pressure receiving area A ₃ the pressure receiving area A ₂ which faces the pressure chamber 93 of the pressure piston 78 faces the pressure chamber 93 of the input piston 94 (A ₂ <A _3), the pressure piston in comparison with the forward movement of the input piston 94 78, that is, the amount of advance of the spool 74 is large, and the operating force required to advance the spool 74 until communication between the input port 80 and the output port 81 is required is relatively small.

At the time of such braking, when the pedaling force of the brake pedal 1 becomes excessive and the wheels are likely to be locked, the inflow valve 6 corresponding to the wheels which are about to be locked.
_FL, is excited to 6 _FR, 6 _R, passage 41 and the liquid pressure transmission unit 4 _FL, 4 _FR between, as well as to block between passage 42 and liquid pressure transmission unit 4 _R. This suppresses an increase in the braking force to avoid the wheels from being locked.
If the wheel is still going to lock up,
The corresponding outlet valves 7 _FL, 7 _FR, 7 to energize the _R and the liquid pressure transmission unit 4 _FL to 4 _R input fluid pressure chamber 19 communicates with the reservoir R, a locking tendency of the wheels by lowering the brake pressure Can be eliminated.

When such anti-lock control is executed, the spool 74 slides back and forth with the fluctuation of the hydraulic pressure in the reaction chamber 75. However, the pressure receiving area A _{1 of the} spool 74 facing the reaction chamber 75 and the pressure chamber Since there is a relationship of A ₁ <A ₂ <A ₃ between the pressure receiving area A ₂ of the pressing piston 78 facing the 93 and the pressure receiving area A ₃ of the input piston 94 facing the pressure chamber 93, the front and rear of the spool 74 The volume fluctuation of the pressure chamber 93 due to the sliding is relatively small, and therefore, the kickback acting on the brake pedal 1 due to the fluctuation of the hydraulic pressure of the reaction force chamber 75 can be suppressed relatively small.

It is assumed that the output pressure of the hydraulic pressure supply source 3 drops abnormally due to a failure of the hydraulic pump 10 or the like during the braking. In this case, the bypass valve 23 in each of the hydraulic pressure transmission units 4 _FL , 4 _FR , 4 _R opens in response to a decrease in the hydraulic pressure output from the control hydraulic pressure output unit 2 to the passage 43. Therefore, the hydraulic pressure generated in the pressure chamber 93 in response to the forward operation of the input piston 94 by the depression operation of the brake pedal 1 is transmitted through the passage 108, the differential pressure valve 136, the annular chamber 139, and the passage 24 to the hydraulic pressure transmission units 4 _FL and 4 _FL . _{It is} supplied from the bypass valve 23 of the _{FR to} the brake devices B _FL and B _FR for the front wheels, respectively, and to the brake devices B _RL and B _RR for the rear wheels via the bypass valve 23 and the proportional pressure reducing valve 5 of the hydraulic pressure transmission unit 4 _R. Will be given. Therefore, even when the output pressure of the hydraulic pressure supply source 3 is abnormally reduced, the hydraulic pressure generated in the pressure chamber 93 of the auxiliary hydraulic pressure generation means 61 acts on each of the brake devices B _FL , B _FR , B _RL , and B _RR . Can be done. Moreover the pressure receiving area A ₂ of the pressure piston 78 facing the pressure chamber 93 is smaller than the pressure receiving area A ₃ of the input piston 94 facing the pressure chamber 93, compares the volumetric change of the pressure chamber 93 due to the forward movement of the pressure piston 78 The ineffective stroke of the brake pedal 1 can be reduced.

At this time, the stroke accumulator 113
Then, as the output hydraulic pressure of the hydraulic pressure supply source 3 decreases, the hydraulic pressure in the pilot chamber 117 abnormally decreases, whereby the backup piston 118 moves forward and abuts on the retainer 132, and further, the retainer 132 The backup spring 121, which has a large spring load, comes into contact with the flange portion 134a of the
16 will be affected. Therefore, the hydraulic pressure source 3
When the output hydraulic pressure abnormally decreases, the hydraulic pressure generated in the pressure chamber 93 is not unnecessarily consumed by the stroke accumulator 113, and the depressing stroke of the brake pedal 1 does not become unnecessarily large.

In the auxiliary hydraulic pressure generating means 61 of the control hydraulic pressure output unit 2, a spring 95 having a large spring load is provided between the input piston 94 and the pressing piston 78.
A spring 96 having a small spring load is interposed in series.
Therefore, the spring reaction force with respect to the stroke of the input piston 94 is as shown in FIG. That is, the spring reaction force to the input piston 94 reaches the stroke amount S _A from the start of forward increases gradually to reach a predetermined value P _A,
The stroke of the input piston 94 exceeds the stroke S _A spring reaction sharply increases. This way,
When a failure occurs in the hydraulic system communicating with the pressure chamber 93 in a state where the output pressure of the hydraulic pressure supply source 3 is normal, a relatively large spring reaction force is applied to the input piston 94 to cause the pedal of the brake pedal 1 to operate. stroke increase is suppressed to a degree that exceeds slightly the stroke amount S _a, and the pressure chamber 93
The degree hydraulic system is normal when the output pressure of the hydraulic pressure source 3 is abnormally low, the spring reaction force increase acting from the input piston 94 to the brake pedal 1 exceeds slightly the predetermined value P _A leading to Can be suppressed.

Further, when the driving force of the engine becomes excessive during non-braking and the driving wheels are likely to slip excessively,
The normally open solenoid valve 8 and the normally closed solenoid valve 9 for traction control are excited. As a result, the output hydraulic pressure of the hydraulic pressure supply source 3 acts on the input hydraulic chamber 19 of the hydraulic pressure transmission units 4 _FL and 4 _FR , and braking force is generated by the brake devices B _FL and B _FR of the left and right front wheels that are the driving wheels. Thus, the occurrence of excessive slip is avoided. Thereafter, as in the case of the antilock control described above, the inflow valve 6
_FL, the excitation and demagnetization control of the 6 _FR and the outlet valve 7 _FL, 7 _FR, can control the braking force.

In such a brake pressure control device, in the control hydraulic pressure output unit 2, the axial position of the small cylinder body 62 in the cylinder body 64 in the hydraulic pressure control valve 62 is determined according to the thickness of the spacer 60. In order to minimize the initial distance between the front end of the pressing piston 78 and the rear end of the spool 74, a simple adjustment that only changes the thickness of the spacer 60 is performed.
, And the initial interval between the rear end of the spool 74 and the rear end of the spool 74 can be minimized, and it is not necessary to perform complicated adjustment on the push rod 99 side.

In the early stage of the braking operation, the hydraulic pressure is not applied to the reaction force chamber 75 until the hydraulic pressure output from the output port 81 of the control hydraulic pressure output unit 2 reaches a certain value. Since the differential pressure valve 85 for preventing the operation reaction force from acting on the plug member 70, which is a component of the control hydraulic pressure output unit 2, is provided, a compact configuration can be achieved.

Each of the hydraulic pressure transmission units 4 _FL , 4 _FR , 4 _R
The breathing action of the output hydraulic chamber 20 can be performed by the seal member 28 mounted on the outer periphery of the free piston 21, and the breathing of the passage 24 leading to the valve chamber 33 of each bypass valve 23 is performed by the accumulator piston 116 in the stroke accumulator 113. The one-way valve for producing a respiratory action is organically integrated into the free piston 21 and the accumulator piston 116, respectively, so that a compact configuration can be achieved. be able to. Further, the accumulator piston 116 has a differential pressure valve 13 for preventing the hydraulic pressure in the pressure chamber 93 from acting on the bypass valve 23 until the pressure in the pressure chamber 93 becomes a predetermined value or more.
6, the configuration can be made more compact.

Further, the hydraulic pressure supply source 3 is connected to the hydraulic pressure control valve 62 through the passage 112, the pilot chamber 117 and the passage 83.
Of the pilot chamber 11
The hydraulic fluid in 7 flows in accordance with the operation of the hydraulic pressure control valve 62, so that air does not accumulate in the pilot chamber 117, and the hydraulic pressure of the hydraulic pressure supply source 3 is wastefully consumed to compress the air. Therefore, the amount of hydraulic pressure consumed by the hydraulic pressure supply source 3 in the pilot chamber 117 can be reduced.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various designs can be made without departing from the present invention described in the claims for utility model registration. Changes can be made.

[0075]

As described above, according to the present invention, the pressing member is interlocked with and connected to the piston with the maximum distance between the pressing member and the piston being regulated, and the valve housing is provided between the cylinder body and the cylinder body. A small cylindrical body fitted and fixed to the cylinder body with an axial direction adjusting means interposed therebetween, and the spool is restricted in its retreat limit position with respect to the small cylinder body and slides on the small cylinder body. Since the small cylinder body is movably fitted, the axial position of the small cylinder body in the cylinder body can be easily adjusted by the axial position adjusting means, and the initial adjustment of the interval between the spool and the pressing member is extremely easily performed. be able to.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram of a brake pressure control device.

FIG. 2 is a longitudinal sectional view illustrating a configuration of a hydraulic pressure transmission unit.

FIG. 3 is a vertical cross-sectional view of the distribution control unit.

FIG. 4 is a longitudinal sectional view showing a partial configuration of a control hydraulic pressure output unit.

FIG. 5 is a longitudinal sectional view showing the remaining configuration of the control hydraulic pressure output unit.

FIG. 6 is a longitudinal sectional view showing a configuration of a stroke accumulator.

FIG. 7 is a diagram showing a relationship between an input piston stroke and a spring reaction force in the auxiliary hydraulic pressure generating means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Brake pedal as an operating member 3 ... Hydraulic pressure supply source 60 ... Spacer as axial position adjustment means 63 ... Valve housing 64 ... Cylinder body 65 ... Small cylinder body 74 ... Spool 75 ... Reaction chamber 78 ... Pressing piston as pressing member 81 ... Output port 93 ... Pressure chamber 94 ... Piston R ... Reservoir

Continuation of front page (72) Inventor Shohei Matsuda 1-4-1 Chuo, Wako-shi, Saitama Pref. Honda Technical Research Institute Co., Ltd. (56) References (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] A piston (94) interlocked and connected to an operation member (1) is slidably fitted to a cylinder body (64) with its front surface facing a pressure chamber (93), and an output port ( The valve housing (63) having the above (81) and being connected to the cylinder body (64) receives the hydraulic pressure of the reaction force chamber (75) communicating with the output port (81) in the retreating direction and in the retreating direction. The spool (74), which is spring-biased, moves the output port (81) to the retreat position for communicating with the reservoir (R) and the hydraulic pressure supply source (3) for outputting a constant output hydraulic pressure to the output port (81). The piston (9) is slidably fitted so as to be movable between forward positions to communicate with the piston (9).
In a hydraulic pressure control device in which a pressing member (78) linked to and connected to 4) abuts on the rear end of the spool (74),
The pressing member (78) is interlocked and connected to the piston (94) with the maximum distance between the pressing member (78) and the piston (94) being regulated. The valve housing (63) includes a cylinder body (64) and the cylinder body (64). And a small cylindrical body (65) fitted and fixed to the cylinder body (64) with an axial position adjusting means (60) interposed therebetween.
4) A hydraulic pressure control device characterized in that its retreat limit position with respect to the small cylinder body (65) is regulated and slidably fitted to the small cylinder body (65).