JPH08188143A - Braking hydraulic controller - Google Patents

Abstract

PURPOSE: To prevent an excessive operational input from acting on an operating force detecting means, in this braking hydraulic controller, capable of imparting any hydraulic pressure to be outputted from a braking hydraulic pressure generating means to a wheel brake according to the detected value of this operating force detecting means detecting the operating force of a brake operating member. CONSTITUTION: A linkage piston 35 forming a pressure chamber 34 in a gap with an operating piston 33 is slidably fitted in a cylinder body 27, and an operating force detecting means S is installed in a master cylinder M after clamping a housing 60 with a detecting part 61a to the cylinder body 27 at the more front side than the linkage piston 35, and an elastic member 81 is interposed between the detecting part 61a and the linkage piston 35. In addition, a regulating member 64 regulating a forward limit of the linkage piston 35 to the operating force detecting means S is interposed between a part other than the detecting part 61a of the housing 60 and the linkage piston 35.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a master cylinder in which an operating piston which is interlocked with and connected to a brake operating member is slidably fitted to a cylinder body with its front face facing a pressure chamber, and a brake operating. An operating force detecting means for detecting an operating force of a member, a braking hydraulic pressure generating means having an electric actuator and capable of giving an output hydraulic pressure to a wheel brake according to the operation of the electric actuator, and the operating force detecting means. And a control means for controlling the operation of the electric actuator according to the detected value.

[0002]

2. Description of the Related Art Conventionally, such a braking hydraulic pressure control device is already known, for example, from Japanese Patent Laid-Open No. 61-155047.

[0003]

SUMMARY OF THE INVENTION In the above conventional one,
A load sensor is attached to the push rod that connects the brake pedal to the working piston of the master cylinder.When an excessive operating force is input from the brake pedal,
The excessive input may directly act on the load sensor and damage the load sensor.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a braking fluid pressure control device which prevents damage to the operating force detection means due to an excessive operation input.

[0005]

In order to achieve the above-mentioned object, the present invention is such that an actuating piston that is interlocked with and connected to a brake operating member is slidably fitted to a cylinder body with its front face facing the pressure chamber. A master cylinder composed of a combination, an operating force detecting means for detecting an operating force of a brake operating member, and an electric actuator, and a braking hydraulic pressure capable of giving an output hydraulic pressure corresponding to the operation of the electric actuator to a wheel brake. In a braking hydraulic pressure control device including a generation means and a control means for controlling the operation of an electric actuator according to a detection value of the operating force detection means, an interlocking piston that forms a pressure chamber with the operation piston is a cylinder. The interlocking piston, which is slidably fitted to the body and forms a pressure chamber with the working piston, is slidably fitted to the cylinder body, and the operating force detection means detects it. Is attached to the master cylinder by fixing a housing having a front side of the interlocking piston to the cylinder body, and an elastic member is interposed between the detecting part and the interlocking piston, and the part other than the detecting part of the housing is interlocked with the piston. A regulating member for regulating the forward limit of the operation force detecting means of the interlocking piston is interposed between and.

[0006]

According to the above construction, the operation input of the brake operating member is converted into the pressure in the pressure chamber, and the pressing load of the interlocking piston due to the pressure is input to the operating force detecting means via the elastic member. Moreover, since the forward limit of the interlocking piston is restricted by the restriction member, an excessive operation input is not input to the operation force detection means.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show a first embodiment of the present invention. FIG. 1 is an overall hydraulic circuit diagram, FIG. 2 is a vertical sectional side view of a master cylinder, and FIG. It is a figure.

First, in FIG. 1, this brake fluid pressure control device outputs a brake fluid pressure in accordance with a depression operation of a brake pedal 1 as a brake operating member.
And a load sensor S as an operation force detecting means attached to the master cylinder M to detect the stepping operation force of the brake pedal 1, and an output hydraulic pressure higher than the output hydraulic pressure of the master cylinder M to generate a wheel brake. B, a braking fluid pressure generating means A, a switching valve 7 which is selectively switchable between the master cylinder M and the braking fluid pressure generating means A and can be connected to the wheel brake B, and a detection value of the load sensor S. And an electronic control unit 8 as control means for controlling the operation of the braking fluid pressure generating means A.

The braking hydraulic pressure generating means A includes a hydraulic pressure supply source 4,
A hydraulic pressure control valve 5 connected to the hydraulic pressure supply source 4 and a linear solenoid 6 as an electric actuator for operating the hydraulic pressure control valve 5 are configured.

The hydraulic pressure supply source 4 includes a hydraulic pump 10 for pumping hydraulic fluid from a reservoir 9, an accumulator 11 connected to the hydraulic pump 10, and a pressure switch for controlling the operation of the hydraulic pump 10. 12 and.

The linear solenoid 6 applies a forward thrust to the hydraulic pressure control valve 5 according to the amount of exciting current of the coil 23, and the amount of exciting current of the coil 23 corresponds to the amount of depression of the brake pedal 1. It is controlled by the electronic control unit 8 based on the detection value of the load sensor S that detects a corresponding value.

The hydraulic pressure control valve 5 has an output port 18, an input port 19 communicating with the hydraulic pressure supply source 4, and a release port 20 communicating with the reservoir 9, and the hydraulic pressure supply source 4
Is adjusted to a value according to the thrust applied from the linear solenoid 6 and output from the output port 18.

The switching valve 7 is the output port 1 of the hydraulic pressure control valve 5.
8 is a 3-port 2-position switching valve that performs switching operation using the hydraulic pressure output from No. 8 as a pilot pressure. When the hydraulic pressure of a predetermined value or more is output from the output port 18, the output port 18 of the hydraulic pressure control valve 5 is connected to the wheel. It is possible to switch between a position for communicating with the brake B and a position for communicating the output port 36 of the master cylinder M with the wheel brake B when the output hydraulic pressure of the output port 18 is less than a predetermined value. Thus, the switching valve 7 is in a state in which the output port 18 of the hydraulic pressure control valve 5 is in communication with the wheel brake B during normal braking, but the hydraulic pressure is reduced due to a failure of the hydraulic pressure supply source 4 and the linear solenoid 6, or the like. When it becomes difficult to obtain the braking pressure from the output port 18 of the control valve 5, the output port 36 of the master cylinder M is brought into communication with the wheel brake B.

Between the output port 36 of the master cylinder M and the switching valve 7, the brake pedal 1 is depressed when the switching valve 7 communicates the output port 18 of the hydraulic control valve 5 with the wheel brake B. A stroke accumulator 26 for ensuring a stroke is connected.

In FIG. 2, in the cylinder body 27 of the master cylinder M, a screw hole 28, a large-diameter cylinder hole 29, and a small-diameter cylinder hole 30 having a smaller diameter than the large-diameter cylinder hole 29 are arranged in this order from the front end side. A fitting hole 31 having a diameter larger than that of the small-diameter cylinder hole 30 is sequentially and coaxially provided, and the small-diameter cylinder hole 30 is provided with a cup seal 32, which is in sliding contact with the inner surface of the cylinder hole 30, on the outer circumference. 33
And an interlocking piston 35 that forms a pressure chamber 34 between the operating piston 33 and the working piston 33, and a cup seal 37 that slidably contacts the inner surface of the small diameter cylinder hole 30 is attached to the outer periphery of the interlocking piston 35. To be done. Further, the cylinder body 27 is provided with an output port 36 which is in constant communication with the pressure chamber 34,
The output port 36 is connected to the switching valve 7.

A piston rod 39, which is slidably supported by a bearing member 38 fitted in the fitting hole 31, is coaxially and integrally connected to the working piston 33. A push rod 40 connected to the brake pedal 1 (see FIG. 1) is connected so as to be swingable.

In the pressure chamber 34, a space is provided between the working piston 33 and the interlocking piston 35, and both pistons 33, 35 are contracted.
Return spring 4 that exerts a spring force in the direction that separates each other
1 is stored.

An annular replenishing liquid chamber 43 is defined between the working piston 33 and the bearing member 38. On the other hand, a reservoir 45 is attached to the liquid reservoir 44 provided above the cylinder body 27, and the replenishment liquid chamber 43 is connected to the liquid reservoir 4 in the reservoir 45.
The cylinder body 27 is provided with a relief port 46 communicating with the cylinder 4. Thus, the cup seal 32 is provided in the replenishing liquid chamber 43.
It is mounted on the outer circumference of the working piston 33 at a position further forward than the working piston 33, and the working piston 33 is provided with a communication hole 47 for communicating the replenishment liquid chamber 43 with the back surface of the cup seal 32.

A central relief valve 48 is provided between the replenishing liquid chamber 43 and the pressure chamber 34. This relief valve 48
Is a valve box 49 that is coaxially attached to the front end portion of the operating piston 33, and is drilled coaxially with the operating piston 33 by communicating with the replenishing liquid chamber 43.
Of the valve hole 50, which is opened in the front end of the valve hole 50, a valve body 51 which is housed in the valve box 49 so that the front end opening of the valve hole 50 can be closed, and is movable back and forth. When the operating piston 33 is in the retreat limit, the valve element 51 exerts a spring force for urging the valve spring 51 in the forward direction and moves the valve element 51 against the spring urging force of the valve spring 52 to the forward position. Is held at the valve spring 52 when the working piston 33 moves forward.
And a valve opening rod 53 that allows the valve body 51 to move backward, that is, to close the valve.

The operating piston 33 has the operating piston 3
3, a long hole 54 is provided in the axial direction, and both ends of the long hole 54 communicate with the replenishing liquid chamber 43. The valve opening rod 53 has a long hole 54.
Both ends of the valve opening rod 53 are supported by a support ring 55 that surrounds the piston rod 39. Further, although not clearly shown, a spring is contracted between the working piston 33 and the support ring 55, and the support ring 55 is urged by the spring force in a direction to be received by the bearing member 38.

The valve hole 50 includes an elongated hole 54 and an operating piston 33.
The rod 5 which is provided over the front end portion of the rod 5 and is integrally connected to the valve body 51 and inserted into the valve hole 50.
The rear end of 6 is brought into contact with the valve opening rod 53.

According to such a relief valve 48, when the working piston 33 is in the retracted limit, the rod 56 is pressed by the valve opening rod 53 so that the valve body 51 is in a position to open the valve hole 50. By opening the valve, the replenishing liquid from the replenishing liquid chamber 43 can be replenished to the pressure chamber 34. Also the working piston 33
Is moved forward from the backward limit, the valve opening rod 53 moves relative to the actuating piston 33 so that the valve opening rod 53 is positioned rearward in the elongated hole 54, so that the valve body 51 moves the valve hole 50 by the spring force of the valve spring 52. It moves to the closed position, and the replenishing liquid chamber 43 and the pressure chamber 34 are shut off from each other.

Referring also to FIG. 3, the housing 60 of the load sensor S has a housing main body 61 formed in a bottomed cylindrical shape, and is caulked to the housing main body 61 so as to close the opening of the housing main body 61. Lid member 62 to be joined
The housing main body 61 is provided with a detection portion 61a protruding in a pin shape on the outer surface of the central portion of the closed end thereof. The lid member 62 is made of a non-conductive material such as synthetic resin, and a connector (not shown) connected to a connection line for guiding a signal from the load sensor S is inserted into and removed from the lid member 62. A coupler 62a for integrally connecting is provided integrally.

In such a load sensor S, a male screw 74 is engraved on the outer surface of the housing main body 61,
A load sensor S is attached to the master cylinder M such that the male screw 74 is screwed into the screw hole 28 of the cylinder body 27.

The interlocking piston 35, which is slidably fitted in the small-diameter cylinder hole 30 of the cylinder body 27, can be brought into contact with the housing 60 of the load sensor S attached to the front end of the cylinder body 27. cylindrical regulating member 64 ₁ slidably fitted in the large-diameter cylinder hole 29 of the 27 are provided integrally, the regulating member 64 ₁ in a portion other than the detection portion 61a of the housing 60 in the load sensor S The contact limit of s with defines the forward limit of the interlocking piston 35 with respect to the load sensor S.

A load transmitting means 75 is provided between the interlocking piston 35 and the load sensor S so as to be housed in the regulating member 64 _{1. The} load transmitting means 75 is provided.
Is a pressing member 8 that abuts the detection portion 61a of the load sensor S.
0 and an elastic member 81 interposed between the pressing member 80 and the interlocking piston 35. Thus, the pressing member 8
0 is a dish-shaped portion 8 slidably fitted to the regulating member 64 _1.
0a and the interlocking piston 35 from the central portion of the dish-shaped portion 80a.
And the shaft portion 80b protruding to the side,
A bottomed fitting hole 82 into which the shaft portion 80b is slidably fitted is provided in the. The elastic member 81 is, for example, a disc spring, and a plurality of elastic members are combined to be interposed between the pressing member 80 and the interlocking piston 35. Instead of the disc spring,
A coil spring or rubber may be used.

By the way, as shown in FIG.
At the time of operation, the working piston 33 and the interlocking piston 35
With the shaft portion 80b of the pressing member 80 in the state of being retracted.
Distance L between closed end of fitting hole 82 of moving piston 35
₁Is a regulating member 64 that is integral with the interlocking piston 35.₁When
Distance L between the load sensor S and the housing 60₂that's all
(L ₁≧ L₂) Is set. This
The interlocking piston 35 moves to the side close to the load sensor S.
Directly from the interlocking piston 35 to the pressing member 80
Of the load from the interlocking piston 35
It is given to the load sensor S without fail via the elastic member 81.
Will be.

The operation of the first embodiment will now be described. When a normal braking pressure can be obtained from the braking fluid pressure generating means A, that is, the output port 18 of the fluid pressure control valve 5, the depression operation of the brake pedal 1 is performed. Accordingly, the switching valve 7 is in a state where the output port 18 of the hydraulic control valve 5 is connected to the wheel brake B, and in this state, the depression sensor operating force of the brake pedal 1 is detected by the load sensor S. That is, at the time of forward movement of the working piston 33, the operating force is transmitted to the interlocking piston 35 via the return spring 41 in the initial operation until the relief valve 48 is closed, and after the relief valve 48 is closed, the forward movement of the working piston 33 is performed. The hydraulic pressure of the pressure chamber 34 generated in accordance with the above is applied to the back surface of the interlocking piston 35, and the load from the interlocking piston 35 acts on the detecting portion 61a of the load sensor S via the load transmitting means 75. Thus, the load sensor S detects the depression operation force of the brake pedal 1. Thus, the exciting current amount of the linear solenoid 6 in the braking fluid pressure generating means A is determined by the load sensor S.
Is controlled by the electronic control unit 8 according to the detected value of
As a result, the braking hydraulic pressure amplified corresponding to the depression operation force of the brake pedal 1 acts on the wheel brake B.

At this time, even if the operating force of the brake pedal 1 is excessive, the limit of the forward movement of the interlocking piston 35 is caused by the restriction member 64 ₁ integral with the interlocking piston 35 contacting the housing 60 of the load sensor S. Since the load sensor S is regulated, it is possible to prevent an excessive operating force from acting on the load sensor S and prevent the load sensor S from being damaged.

Further, the interlocking piston 35 and the load sensor S
Elastic member 81 included in the load transmission means 75 interposed therebetween
When the rubber is made of rubber, it is possible to avoid the impact load being applied to the load sensor S by absorbing a sudden load by the elastic member 81.

As a second embodiment of the present invention, as shown in FIG. 4, the housing 60 of the load sensor S may be integrally provided with a cylindrical restricting member 64 ₂ capable of contacting the interlocking piston 35. As a third embodiment of the present invention, as shown in FIG. 5, between the housing 60 and the interlocking piston 35 of the load sensor S, a cylindrical restricting member which is a separate member from both the housing 60 and the interlocking piston 35. 6
4 ₃ may be arranged.

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 claims. It is possible to do.

For example, the braking fluid pressure generating means may be one in which a motor is connected to a piston facing the fluid pressure generating chamber via a ball screw, and the switching valve is an output fluid of the master cylinder. It may be configured as a high select valve in which either the pressure or the output hydraulic pressure of the braking hydraulic pressure generating means is selectively selected to act on the wheel brakes, and the switching valve is electrically switched. It may be operated.

[0035]

As described above, according to the present invention, an interlocking piston that forms a pressure chamber with the working piston is slidably fitted in the cylinder body, and the operating force detecting means has a detecting portion. The housing is fixed to the cylinder body in front of the interlocking piston, and is attached to the master cylinder. An elastic member is interposed between the detecting portion and the interlocking piston, and a portion other than the detecting portion of the housing and the interlocking piston are provided. Since a restricting member for restricting the forward limit of the operation force detecting means of the interlocking piston is interposed between them, the operation input of the brake operating member converted into the pressure of the pressure chamber causes the operation of the interlocking piston due to the pressure. Accordingly, it is input to the operating force detecting means via the elastic member. Moreover, since the forward limit of the interlocking piston is regulated by the regulation member, it is possible to prevent an excessive operation input from acting on the detection portion of the operation force detection means and prevent the operation force detection means from being damaged.

[Brief description of drawings]

FIG. 1 is an overall hydraulic circuit diagram of a first embodiment.

FIG. 2 is a vertical sectional side view of a master cylinder.

FIG. 3 is an enlarged view of part 3 in FIG.

FIG. 4 is a sectional view corresponding to FIG. 3 of the second embodiment.

5 is a sectional view of a third embodiment corresponding to FIG.

[Explanation of symbols]

1 ... Brake pedal as brake operating member 6 ... Linear solenoid as electric actuator 8 ... Electronic control unit as control means 27 ... Cylinder body 33 ... Operating piston 34 ... Pressure Chamber 35 ... Interlocking piston 35a ... Skirt portion 60 ... Housing 61a ... Detection portion 64 ₁ , 64 ₂ , 64 ₃ ... Restricting member 81 ... Elastic member A ... Braking hydraulic pressure Generating means B ... Wheel brake M ... Master cylinder S ... Load sensor as operating force detecting means

Claims (1)

[Claims] 1. An operating piston (33) interlockingly connected to a brake operating member (1) has a pressure chamber (34) on its front surface.
A master cylinder (M) slidably fitted to the cylinder body (27) facing the rear side, and a brake operating member (1)
A braking fluid that has an operating force detection means (S) for detecting the operating force of the electric actuator and an electric actuator (6) and can give an output hydraulic pressure to the wheel brake (B) according to the operation of the electric actuator (6). A braking fluid pressure control device comprising a pressure generating means (A) and a control means (8) for controlling the operation of an electric actuator (6) in accordance with a detection value of the operating force detection means (S). An interlocking piston (35) that forms a pressure chamber (34) with (33) is slidably fitted in the cylinder body (27), and the operating force detecting means (S) operates the detecting section (61a). Housing (6
0) is fixed to the cylinder body (27) in front of the interlocking piston (35) and is attached to the master cylinder (M),
An elastic member (81) is interposed between the detection part (61a) and the interlocking piston (35), and the housing (6)
0) detecting portion (61a) other than the interlocking piston (3
5) and the restriction member (64 ₁ , for restricting the forward limit of the interlocking piston (35) with respect to the operating force detecting means (S).
64 ₂ , 64 ₃ ) is interposed, and a braking fluid pressure control device.