JP3382268B2 - Brake hydraulic pressure generator for vehicles - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake fluid pressure generating device for a vehicle.
About the installation . 2. Description of the Related Art Conventionally , a brake operating member has been linked to an operating member.
First hydraulic pressure generating means such as master cylinder and brake operation
The output hydraulic pressure of the first hydraulic pressure generating means according to the operation input to the member
A second hydraulic pressure generating means capable of outputting a higher hydraulic pressure than
The brake operation member can be operated with relatively small operating force.
Brake fluid pressure for vehicles that can output high braking fluid pressure
The device is already known. [0003] The above-described vehicle brake hydraulic pressure device
The output hydraulic pressure from the second hydraulic pressure generating means is normal.
When it is supplied to the wheel brake,
When the output hydraulic pressure from the pressure generating means drops abnormally, the first liquid
The fluid that supplies the output fluid pressure from the pressure generating means to the wheel brake
Pressure supply means, and the second hydraulic pressure generating means
High braking effect is obtained by using the output hydraulic pressure from the stage
And abnormal output hydraulic pressure from the second hydraulic pressure generating means
When the pressure drops, substitute the output hydraulic pressure from the first hydraulic pressure generating means
Fail-safe means for securing braking are known.
However, the above hydraulic pressure selective supply means has a structure.
As simple as possible, and from the first and second hydraulic pressure generating means to the wheels
Smooth switching of output hydraulic pressure to brake
Is desirable. [0004] The present invention has been made in view of such circumstances, and a vehicle control system capable of satisfying the above demands.
It is an object to provide a hydraulic pressure generating device . [0005] To achieve the above object, according to the present invention, a brake operation member is interlocked and connected.
For the first hydraulic pressure generation means and the operation input to the brake operation member
Accordingly, a hydraulic pressure greater than the output hydraulic pressure of the first hydraulic pressure generating means
Outputtable second hydraulic pressure generating means, and second hydraulic pressure generating means
When the output hydraulic pressure from the
When the output hydraulic pressure drops abnormally, the first
The fluid that supplies the output fluid pressure from the pressure generating means to the wheel brake
In a vehicle brake hydraulic device provided with a pressure selective supply means, the hydraulic pressure selective supply means includes a first hydraulic pressure chamber communicating with the first hydraulic pressure generation means, and a second hydraulic pressure generation means. the spool to face at both ends and a second pressure chamber leading to slidably fitted into the valve housing a receiving area facing those of the liquid chamber as the same
Is composed of changeover valve comprising Te, the said valve housing, an output port volume, of the two hydraulic chambers are communicated to the increase side according to the axial movement of the spool, fluid pressure is applied to both hydraulic chambers
If not, connect the second hydraulic chamber to the output port.
Urging means for urging the spool in a predetermined direction . An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a first embodiment of the present invention. FIG. 1 is a brake hydraulic system diagram when applied to a vehicle brake system, and FIG. 2 is a longitudinal sectional view of a switching valve. is there. First, in FIG. 1, the brake 1 mounted on the wheel W has a higher output hydraulic pressure of the master cylinder 2 as the first hydraulic pressure generating means and a higher output hydraulic pressure of the second hydraulic pressure generating means 3. The hydraulic pressure of the other is applied,
A switching valve 4 as a hydraulic pressure selective supply means of the present invention is interposed between the brake 1, the master cylinder 2, and the second hydraulic pressure generation means 3. The master cylinder 2 is a conventional cylinder connected to a brake pedal 5 operated by a vehicle driver via a negative pressure booster 6, and a force obtained by boosting the operating force of the brake pedal 5 is applied to the negative pressure booster. 6 to the master cylinder 2, whereby the brake hydraulic pressure is output to a first output hydraulic passage 8 communicating with the output port 7 of the master cylinder. In addition, when the second hydraulic pressure generating means 3 is operating normally, the output hydraulic pressure of the master cylinder 2 is not applied to the brake 1 by the function of the switching valve 4, and the brake pedal 5 at that time is not operated. First to secure operation stroke
A stroke accumulator 9 is connected to the output hydraulic pressure path 8. The second hydraulic pressure generating means 3 includes a brake pedal 5
Can output a braking fluid pressure greater than the output fluid pressure of the master cylinder 2 in accordance with the operating force of the master cylinder 2.
And a hydraulic control valve 11 and a linear solenoid 12 for operating the hydraulic control valve 11. The hydraulic pressure source 10 includes a hydraulic pump 14 for pumping hydraulic fluid from a reservoir 13, an accumulator 15 connected to the hydraulic pump 14, and a pressure switch 16 for controlling the operation of the hydraulic pump 14. And a hydraulic pressure higher than the output hydraulic pressure of the master cylinder 2 can be output. The hydraulic pressure control valve 11 has an input port 17 communicating with the hydraulic pressure supply source 10 and a release port 1 communicating with the reservoir 13.
8 and a housing 20 having an output port 19 to which the second output hydraulic path 22 is connected, between a forward position where the output port 19 communicates with the input port 17 and a retracted position where the output port 19 communicates with the release port 18. The spool 21 is slidably fitted so as to be able to move, and a reaction force chamber 23 communicating with the output port 19 is formed in the housing 20 so as to face the front end of the spool 21. The housing 20 is formed in a cylindrical shape with a bottom having an output port 19 at a front end closing portion, and an annular recess 24 communicating with the input port 17 is formed on the inner surface of the housing 20 on the front side in the axial direction. An annular recess 25 which is provided on the right side in FIG. 1 and communicates with the release port 18 is provided on the rear side in the axial direction (left side in FIG. 1). An annular groove 26 is provided on the outer surface of the spool 21 so as to communicate with the annular concave portion 25 at the retracted position but communicate with the annular concave portion 24 at the advanced position. The annular groove 26 communicates with the reaction force chamber 23. . Further, a return spring 27 for urging the spool 21 rearward is housed in the reaction force chamber 23. The linear solenoid 12 includes a housing 20
The drive rod 28 of the linear solenoid 12 is coaxially abutted on the rear end of the spool 21. The linear solenoid 12 applies a thrust in the forward direction to the spool 21 in accordance with the amount of input electricity. When the thrust in the forward direction is applied to the spool 21 from the linear solenoid 12, the spool 21 Moves forward to a forward position where the input port 17 communicates with the reaction force chamber 23, that is, the output port 19. Thus, the spool 21 is given a reaction force in the retreating direction by the liquid pressure in the reaction force chamber 23, and the spool 21 is moved backward by the thrust in the forward direction from the linear solenoid 12 and the liquid pressure in the reaction force chamber 23. The fluid is moved back and forth within the housing 20 so that the force in the direction is balanced, whereby the output hydraulic pressure of the hydraulic pressure supply source 10 is controlled to a value corresponding to the thrust of the linear solenoid 12 in the forward direction, and the output hydraulic pressure is output from the output port 19. Will be output. The operation of the linear solenoid 12 is controlled by a control unit 29. The control unit 29 applies a signal to the linear solenoid 12 in accordance with a detection value of a sensor 30 for detecting the operation force of the brake pedal 5. The input electric quantity, that is, the output hydraulic pressure from the hydraulic pressure control valve 11 is controlled. When the second hydraulic pressure generating means 3 is operating normally, the switching valve 4 makes the output of the second hydraulic pressure generating means 3 higher than the output hydraulic pressure of the master cylinder 2 in response to the operation of the brake pedal 5. Since the output hydraulic pressure is higher, the output hydraulic pressure of the second hydraulic pressure generating means 3 is selected and applied to the brake 1. When the brake fluid pressure decreases, the output hydraulic pressure of the master cylinder 2 that reliably outputs the brake hydraulic pressure in accordance with the operation of the brake pedal 5 is selected and applied to the brake 1. In FIG. 2, the switching valve 4 has a spool 34 slidably fitted in a sliding hole 33 of a valve housing 32. A first output hydraulic pressure passage is provided in the valve housing 32. The first hydraulic chamber 35 communicating with the spool 8 is formed facing one end of the spool 34, and the second hydraulic chamber 36 communicating with the second output hydraulic passage 22 is formed facing the other end of the spool 34. . The valve housing 32 has a casing 38 having a mounting hole 37 extending in a straight line, and a first input port 39 connected to the first output hydraulic pressure passage 8.
7 and a second output hydraulic pressure path 2
2 having a second input port 41 connected to
A plug 42 screwed to the other end of the plug 7, and both plugs 40, 42
And a guide member 43 fitted and fixed in the mounting hole 37 so as to be sandwiched therebetween. The guide member 43 is formed in a cylindrical shape by forming a sliding hole 33 having the same inner diameter along the axial direction, and is slidably fitted in the sliding hole 33. A first hydraulic chamber 35 is formed between one end of the spool 34 and the plug 40, and a second hydraulic chamber 36 is formed between the other end of the spool 34 and the plug 42. The spool 34 has a sliding hole 33.
A large-diameter portion 34a having an outer surface in sliding contact with the inner surface of the large-diameter portion, and a small-diameter portion 34b coaxially connected to one end of the large-diameter portion 34a;
Small-diameter portion 34c coaxially connected to the other end of large-diameter portion 34a
The pressure receiving areas of the spool 34 facing the first and second hydraulic chambers 35 and 36 are the same. In addition, slits 44a and 44b are provided at the tips of the small diameter portions 34b and 34c to avoid closing the first and second input ports 39 and 41. An annular passage 45 is formed between the outer surface of the guide member 34 and the inner surface of the mounting hole 37, and an output port 46 communicating with the annular passage 45 is formed in the casing 38. Thus, the output port 46 is connected to the brake 1. The guide member 34 has a plurality of first and second valve holes 47... 48 having an inner end opened to the slide hole 33 and an outer end connected to the annular passage 45. Open radially. Thus, the first valve holes 47 ...
When the spool 34 is moving to the side where the volume of the second hydraulic chamber 36 increases as shown in FIG. 2, the spool 34 is closed by the large diameter portion 34a of the spool 34, but the volume of the first hydraulic chamber 35 increases. When the spool 34 moves to the first hydraulic chamber 3
The second valve holes 48 are closed by the large-diameter portion 34a of the spool 34 when the spool 34 is moving to the side where the volume of the first hydraulic chamber 35 increases. As shown in FIG. 2, when the spool 34 moves to the side where the volume of the second hydraulic chamber 36 increases, the spool 34 communicates with the second hydraulic chamber 36. That is, when the spool 34 moves to the side where the capacity of the second hydraulic chamber 36 increases as shown in FIG. 2, the second hydraulic chamber 36 is connected to the output port 46 through the second valve holes 48 and the annular passage 45. When the spool 34 moves to the side where the volume of the first hydraulic chamber 35 increases, the first hydraulic chamber 35 communicates with the output port 46 via the first valve holes 47 and the annular passage 45. Become. In the second hydraulic chamber 36, a spring 49 as urging means is contracted between the plug 42 and the spool 34. The spring load of the spring 49 is set to such a small value that the spool 34 is moved and held until the spool 34 comes into contact with the stopper 40 in a state where no hydraulic pressure acts on both the hydraulic chambers 35 and 36. . Next, the operation of this embodiment will be described. When the brake operation is performed by depressing the brake pedal 5, the output hydraulic pressure of the master cylinder 2 when the second hydraulic pressure generating means 3 is operating normally. The output hydraulic pressure of the second hydraulic pressure generating means 3 is higher than that of the
Is located at a position where it moves rightward as shown in FIG. 2 to increase the volume of the second hydraulic chamber 36. In this state, the first valve holes 47 are closed by the spool 34 and the second hydraulic chamber 36 is closed. 36, that is, the output hydraulic pressure of the second hydraulic pressure generating means 3 is applied to the brake 1 from the output port 46. At the time of such braking, assuming that the output hydraulic pressure of the second hydraulic pressure generating means 3 is reduced due to some malfunction, the output hydraulic pressure of the second hydraulic pressure generating means 3 becomes lower than the output hydraulic pressure of the master cylinder 2. When the pressure is lower than the pressure, since the pressure receiving areas of the spool 34 facing the first and second hydraulic chambers 35 and 36 are the same, the spool 34 immediately moves leftward so as to increase the volume of the first hydraulic chamber 35. The first valve holes 47 communicate with the first hydraulic chamber 35. As a result, the output hydraulic pressure of the master cylinder 2 immediately acts on the brake 1 from the output port 46 instead of the output hydraulic pressure of the second hydraulic pressure generating means 3. Therefore, when the hydraulic pressure is switched, the output port 46
There is no jumping in the output hydraulic pressure from the motor, the switching of the hydraulic pressure is smooth, and no hydraulic fluid flows out at the time of the switching, so that there is no liquid loss. In such a switching valve 4, the outer diameter of the spool 34 can be set relatively small, so that it is possible to contribute to downsizing of the switching valve 4 as a whole. FIG. 3 shows a second embodiment of the present invention, and portions corresponding to those of the first embodiment are denoted by the same reference numerals. In this embodiment, the hydraulic pressure selective supply means
The switching valve 4 'is provided with the sliding hole 3 in the valve housing 32'.
A spool 34 'is slidably fitted to 3'. A first output hydraulic passage 8 is provided in the valve housing 32 '.
A first hydraulic chamber 35 is formed facing one end of the spool 34 ', and a second hydraulic chamber 36 communicating with the second output hydraulic passage 22 is formed facing the other end of the spool 34'. You. The valve housing 32 is connected to the second output hydraulic passage 22.
And a mounting hole 37 'coaxially connected to the second input port 41' through the step 50.
, A plug 40 having a first input port 39 connected to the first output hydraulic pressure passage 8 and screwed to one end of a mounting hole 37 ′, a step portion 50 and a plug 40
A guide member 43 'fitted and fixed in the mounting hole 37' so as to be sandwiched therebetween. The guide member 43 'is formed in a cylindrical shape by forming a sliding hole 33' having the same inner diameter along the axial direction, and is slidably fitted in the sliding hole 33 '. The first hydraulic chamber 3 is located between one end of the spool 34 ′ and the plug 40.
5 is formed, and a second hydraulic chamber 36 is formed between the other end of the spool 34 ′ and the step 50. Also, the spool 34 '
Is a large-diameter portion 34a 'having an outer surface that is in sliding contact with the inner surface of the sliding hole 33' and having a shorter axial length than the large-diameter portion 34a of the spool 34 in the first embodiment. Part 34
a 'small-diameter portion 34b' coaxially connected to one end of the large-diameter portion 34a 'and a small-diameter portion 34 coaxially connected to the other end of the large-diameter portion 34a'.
c ', and the pressure receiving areas of the spool 34' facing the first and second hydraulic chambers 35 and 36 are the same. The outer surface of the guide member 34 'and the mounting hole 37'
An annular path 45 'communicating with the output port 46 provided in the casing 38' is formed between the inner surface of the casing 38 '. The guide member 34 'has a sliding hole 3 at its inner end.
A plurality of valve holes 51 which are opened at 3 'and whose outer end communicates with the annular passage 45' are provided radially.
.. Indicate that the spool 34 'is in the second hydraulic chamber 3 as shown in FIG.
When the spool 34 ′ moves to the side where the volume of the first hydraulic chamber 35 increases, the first hydraulic chamber 35 communicates with the second hydraulic chamber 36 when it moves to the side where the volume of 6 increases. It communicates. According to the second embodiment, the second hydraulic chamber 3
When the hydraulic pressure of 6 is lower than the hydraulic pressure of the first hydraulic chamber 35 for some reason, the pressure receiving areas of the spool 34 'facing the first and second hydraulic chambers 35 and 36 are the same.
The spool 34 'immediately moves to the left so as to increase the volume of the first hydraulic chamber 35, and the valve holes 51 communicate with the first hydraulic chamber 35, so that the hydraulic pressure can be switched quickly. Thus, when the hydraulic pressure is switched, smooth switching can be realized without causing jumping in the output hydraulic pressure from the output port 46, and no liquid loss occurs. Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible to do. As described above, according to the present invention, the brake
First hydraulic pressure generating means interlockingly connected to the operating member;
Output of the first hydraulic pressure generating means according to an operation input to the operation member
Second hydraulic pressure generating means capable of outputting a hydraulic pressure greater than the hydraulic pressure
And the output hydraulic pressure from the second hydraulic pressure generating means is normal
When it is supplied to the wheel brake,
When the pressure drops abnormally, the output hydraulic pressure from the first hydraulic pressure
Vehicle provided with hydraulic pressure selective supply means for supplying to wheel brakes
In the dual-use brake hydraulic device, the hydraulic pressure selective supply means includes:
Spools with both ends facing a first hydraulic pressure chamber communicating with the first hydraulic pressure generating means and a second hydraulic pressure chamber communicating with the second hydraulic pressure generating means
A slidably configured from the fitting and comprising switching valve in the valve housing as the same pressure receiving area facing their hydraulic chamber,
The said valve housing, an output port the volume of both the fluid pressure chamber in response to axial movement of the spool is communicated to the increase side
And the second hydraulic pressure when no hydraulic pressure is applied to both hydraulic chambers.
Set the spool in a predetermined direction so that the chamber communicates with the output port.
And urging means for urging the urging means.
Wheel brake during normal operation of the second hydraulic pressure generation means based on urging force
Can always be in communication with the
Sometimes the output hydraulic pressure of the second hydraulic pressure generating means is applied to the wheel brake.
It can be introduced with good responsiveness. On the other hand, the second hydraulic pressure
When there is a difference between the output hydraulic pressures of the first and second hydraulic pressure generating means due to a decrease in the output hydraulic pressure of the generating means , the difference based on the differential pressure
The first hydraulic pressure generating means
Output fluid pressure to the wheel brakes with good responsiveness.
The switching of output fluid pressure at the time of switching
As a result, the switching of the fluid pressure becomes smooth. The first and second liquids
Fluid for selectively supplying the output fluid pressure of the pressure generating means to the wheel brake
As a pressure selective supply means, a differential pressure responsive type with a relatively simple structure
Can be used to reduce cost
Can contribute to

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a brake hydraulic system diagram of a first embodiment when applied to a vehicle braking device. FIG. 2 is a longitudinal sectional view of a switching valve. FIG. 3 is a longitudinal sectional view of a switching valve according to a second embodiment. DESCRIPTION OF THE REFERENCE NUMERALS 1 brake 2 master cylinder 3 as first hydraulic pressure generating means 2nd hydraulic pressure generating means 4, 4 ' Switching valves 32, 32' as hydraulic pressure selective supply means Valve housing 34, 34 'spool 35 First hydraulic chamber 36 Second hydraulic chamber 46 Output port 49 Spring as urging means

Continuation of the front page (56) References JP-A-5-254421 (JP, A) JP-A-4-25475 (JP, A) JP-A-58-44527 (JP, U) JP-A-58-44528 (JP) , U) Japanese Utility Model Showa 55-22535 (JP, U) Japanese Utility Model Showa 57-144659 (JP, U) Japanese Patent Publication No. 45-25454 (JP, B1) Japanese Utility Model Showa 57-41506 (JP, Y1) (58) Field surveyed (Int. Cl. ⁷ , DB name) B60T 11/28

Claims (1)

(57) [Claims] [Claim 1] Linkedly connected to a brake operating member (5)
To the first hydraulic pressure generating means (2) and the brake operating member (5)
Output hydraulic pressure of the first hydraulic pressure generating means (2) according to the operation input of
Second hydraulic pressure generating means (3) capable of outputting a higher hydraulic pressure than
And the output hydraulic pressure from the second hydraulic pressure generating means (3) is normal
If so, supply it to the wheel brake (1) and
A first hydraulic pressure generating means when the output hydraulic pressure drops abnormally;
Supply output hydraulic pressure from (2) to wheel brake (1)
Vehicular brake fluid provided with hydraulic pressure selective supply means (4, 4 ')
In the pressure generating device , the hydraulic pressure selective supply means includes a first hydraulic pressure chamber (35) communicating with the first hydraulic pressure generating means (2) and a second hydraulic pressure chamber communicating with the second hydraulic pressure generating means (3). spool which has (36) and to face the both ends (34, 34 '), the valve housing pressure receiving area facing their hydraulic chamber (35, 36) as the same (32,3
2 ') to slidably fitted to comprising switching valve (4,4')
Ri is configured, the said valve housing (32, 32 '), the spool (3
, 34 ') in accordance with the axial movement of both hydraulic chambers (35, 3').
6) The hydraulic pressure acts on the output port (46) communicating with the side of increasing the volume and the hydraulic chambers (35, 36).
In the absence state, the second hydraulic chamber (36) is connected to the output port (4
Place spools (34, 34 ') so that they communicate with 6).
Wherein the biasing means (49) for biasing the constant direction is provided, the brake fluid pressure generating apparatus for a vehicle.