JP5337893B2 - Brake device - Google Patents

Description

  The present invention relates to the technical field of brake devices.

  Patent Document 1 discloses a brake device having a plunger pump in which a return spring that biases the plunger in the valve closing direction and a suction valve that biases the valve body of the suction valve in the valve closing direction are provided in a housing that houses the plunger. Is disclosed.

JP 2006-170080 A

However, there is a problem that the number of parts constituting the piston pump is large and the number of assembling steps is increased.
The objective of this invention is providing the brake device which can reduce a number of parts.

In order to achieve the above object, in the brake device of the present invention, a seal shaft that seals the pump cylinder and the eccentric cam rotor chamber in a state of being assembled in the pump cylinder and having a predetermined tightening margin with respect to the outer periphery of the piston. A backup member that performs positioning in the direction, and a bottomed cylindrical member that is fixed to the housing and abuts against the backup member.

  Therefore, in the brake device of the present invention, the number of parts can be reduced.

1 is a hydraulic circuit diagram of a brake device according to a first embodiment. 1 is a cross-sectional view illustrating a configuration of a piston pump P of Example 1. FIG. It is the front view (a) and side surface partial sectional view (b) which show the structure of the bottomed cylindrical member 25 of Example 1. FIG. It is the front view (a) and side surface partial sectional view (b) which show the structure of the bottomed cylindrical member 41 of Example 2. FIG. It is a hydraulic-circuit figure of the brake device of Example 3.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the brake device of this invention is demonstrated based on the Example shown on drawing.
[Example 1]
First, the configuration will be described.
[Hydraulic circuit configuration]
FIG. 1 is a hydraulic circuit diagram of the brake device according to the first embodiment.
The brake device has a piping structure called X piping composed of two systems of P system and S system. The wheel cylinder of the left front wheel FL and the right rear wheel RR is connected to the P system, and the wheel cylinder of the right front wheel FR and the left rear wheel RL is connected to the S system.

In the following description, what is provided in both the P system and the S system, for example, in the case of a reservoir, the reservoir of the P system is represented as 14P, and the reservoir of the S system is represented as 14S. In addition, in the case of a wheel cylinder, for example, a wheel cylinder, the wheel cylinder of the left front wheel FL and the right rear wheel RR connected to the P system is connected to the W / CFL, W / CRR, system. The wheel cylinders for the right front wheel FR and the left rear wheel RL are represented as W / CRL and W / CRL.
In the brake device, since the P system and the S system have the same structure, only the P system will be described, and the description of the S system will be omitted.

  The brake device discharges brake fluid (working fluid) to the housing 1 of the hydraulic control circuit in accordance with the operation of the brake pedal BP. The input rod INR is input by the amount of operation of the brake pedal BP by the driver, and the input of the input rod INR is boosted by the negative pressure booster BO. From the input of the boosted input rod INR, the master cylinder M / C discharges the same amount of brake fluid to the P system and the S system.

The hydraulic control circuit is a brake fluid that flows into the wheel cylinders W / CFL, W / CRR discharged from the master cylinder M / C, or a brake fluid that flows into the wheel cylinders W / CFL, W / CRR to generate a braking force by itself. By controlling the brake fluid flowing into the reservoir 14P from the wheel cylinders W / CFL, W / CRR, the brake pressure of the wheel cylinders W / CFL, W / CRR is controlled, and the braking force of the wheels is controlled.
The master cylinder M / C of the hydraulic control circuit and the suction side of the pump PP are connected by a pipe line 2P. The pump PP of Example 1 uses a piston pump that is a reciprocating pump. A gate-in valve 3P, which is a normally closed electromagnetic valve, is provided on the pipe line 2P. A check valve (suction valve) 4P is provided on the pipeline 2P and between the gate-in valve 3P and the pump PP. This check valve 4P allows the flow of brake fluid in the direction from the gate-in valve 3P to the pump PP and prohibits the flow in the opposite direction.

  The discharge side of the pump PP and the wheel cylinders W / CFL, W / CRR are connected by a pipeline 5P. Solenoid valves 6FL, 6RR, which are normally open solenoid valves corresponding to the wheel cylinders W / CFL, W / CRR, are provided on the pipe line 5P. A check valve (discharge valve) 7P is provided on the pipe line 5P and between the solenoid-in valves 6FL, 6RR and the pump PP. This check valve 7P allows the flow of brake fluid in the direction from the pump PP toward the solenoid-in valves 6FL, 6RR, and prohibits the flow in the opposite direction.

  Further, the pipeline 5P is provided with pipelines 8FL and 8RR that bypass the solenoid-in valves 6FL and 6RR. Check valves 9FL and 9RR are provided in the pipe lines 8FL and 8RR. The check valves 9FL, 9RR allow the flow of brake fluid in the direction from the wheel cylinders W / CFL, W / CRR to the pump PP, and prohibit the flow in the opposite direction.

  Master cylinder M / C and pipe 5P are connected by pipe 10P. The pipeline 5P and the pipeline 10P merge between the pump PP and the solenoid-in valves 6FL and 6RR. A gate-out valve 11P, which is a normally open solenoid valve, is provided on the pipe line 10P. Further, on the pipeline 10P, a pipeline 12P that bypasses each gate-out valve 11P is provided, and a check valve 13P is provided on the pipeline 12P. This check valve 13P allows the flow of brake fluid in the direction from the master cylinder M / C side toward the wheel cylinders W / CFL, W / CRR, and prohibits the flow in the opposite direction.

  A reservoir 14P is provided on the suction side of the pump PP, and the reservoir 14P and the pump PP are connected by a pipe line 15P. A check valve 16P is provided between the reservoir 14P and the pump PP. The check valve 16P allows the flow of brake fluid in the direction from the reservoir 14P to the pump PP, and prohibits the flow in the opposite direction.

  Wheel cylinders W / CFL, W / CRR and pipe 15P are connected by pipe 17P. The pipe line 17P and the pipe line 15P merge between the check valve 4P and the reservoir 14P. Solenoid out valves 18FL and 18RR, which are normally closed solenoid valves, are provided in the pipe line 17P.

[Configuration of piston pump]
FIG. 2 is a cross-sectional view illustrating the configuration of the piston pump P according to the first embodiment. The piston pump P according to the first embodiment includes a pump cylinder 21, a piston 22, an eccentric cam rotor 23, a spherical plug 24, and a bottomed bottom. It has a cylindrical member 25, a suction valve 4, and a discharge valve 7. In the following description, in the axial direction of the piston 22, the surface 1a side of the housing 1 is referred to as an axial positive direction, and the opposite side is referred to as an axial negative direction.

  The pump cylinder 21 is formed so as to penetrate from the surface 1 a of the housing 1 to the eccentric cam rotor chamber 26 provided in the housing 1. An eccentric cam rotor 23 is accommodated in the eccentric cam rotor chamber 26. The eccentric cam rotor 23 is rotationally driven by the motor M, contacts the second end 22b of the piston 22 and moves the piston 22 in the axial positive direction.

  The pump cylinder 21 includes, in order from the eccentric cam rotor chamber 26 in the axial positive direction, the piston 22, the seal 27, the backup member 28, the ball valve body 4a constituting the suction valve 4, the bottomed cylindrical member 25, and the spherical plug 24. Is arranged. Further, on the surface 1a side of the pump cylinder 21, a caulking portion 21a that restricts the movement of the spherical plug 24 in the axial positive direction is formed.

In the pump cylinder 21, a pressure chamber 29 for pressurizing the brake fluid is formed in a space between the spherical plug 24 and the backup member 28.
Both the seal 27 and the backup member 28 are formed in an annular shape, and are attached to the outer periphery of the piston 22 with a predetermined tightening allowance. The seal 27 seals the pressure chamber 29 and the eccentric cam rotor chamber 26, and the backup member 28 prevents the seal 27 from being damaged by protruding by restricting the movement of the seal 27 in the axial positive direction.

  In the housing 1, a suction oil passage 1 b and a discharge oil passage 1 c that are orthogonal to the axial direction of the pump cylinder 21 and communicate with the pressure chamber 29 are formed. The suction oil passage 1b is provided with a filter 30 that removes contamination and the like from the brake fluid. A suction valve 4 is disposed between the suction oil passage 1 b and the pressure chamber 29. The suction valve 4 includes a ball valve body 4a, a seat surface 4b, and a suction spring (suction valve biasing portion 34) that biases the ball valve body 4a toward the seat surface 4b. In the first embodiment, the seat surface 4b of the suction valve 4 is formed in the housing 1, thereby suppressing an increase in the number of parts.

  A discharge valve 7 is disposed between the discharge oil passage 1 c and the pressure chamber 29. The discharge valve 7 includes a ball valve body 7a, a seat surface 7b, and a spring 7c that biases the ball valve body 7a toward the seat surface 7b. A predetermined preload is applied to the spring 7c.

  The bottomed cylindrical member 25 is accommodated in the pressure chamber 29. The bottomed cylindrical member 25 has a bottom portion 31 and a cylindrical portion 32, and is formed using, for example, a spring steel plate. The bottomed cylindrical member 25 is disposed in a state where the bottom 31 faces (is orthogonal to) the piston 22 in the axial direction of the piston 22.

  The bottom 31 of the bottomed tubular member 25 is disposed between the spherical plug 24 and the first end 22a of the piston 22, and serves as a return spring that urges the piston 22 toward the eccentric cam rotor 23, that is, the negative axial direction. The piston urging portion 33 is formed.

Further, the cylindrical portion 32 of the bottomed cylindrical member 25 has a suction spring that biases the ball valve body 4a of the suction valve 4 toward the seat surface 4b formed on the housing 1, that is, the valve closing direction. As a suction valve urging portion 34 is formed.
A part of the outer peripheral surface of the cylindrical portion 32 that contacts the pump cylinder 21 is joined to the inner peripheral surface of the pump cylinder 21. That is, the bottomed cylindrical member 25 is fixed to the housing 1.

FIG. 3 is a front view (a) and a partial side sectional view (b) showing the configuration of the bottomed cylindrical member 25 of the first embodiment.
The piston urging portion 33 is composed of three leaf spring pieces 35 provided on the bottom portion 31. Each leaf spring piece 35 is formed in a substantially rectangular shape and is arranged at equal intervals (120-degree pitch) in the circumferential direction of the cylindrical portion 32. The distal end portion 35 b of each leaf spring piece 35 extends from the base end portion 35 a on the bottom portion 31 side toward the center of the tubular portion 32. Since each base end portion 35 a is bent toward the axially inner side (the top portion 37 side) of the cylindrical portion 32, each leaf spring piece 35 has an angle with respect to the bottom portion 31. In the piston urging portion 33, the pressing force of each leaf spring piece 35 against the piston 22 is set by adjusting the angle with respect to the bottom 31 of each leaf spring piece 35, that is, the bending angle of the base end portion 35a.
The bottom 31 side of each leaf spring piece 35 is in contact with the spherical plug 24. The top portion 37 is in contact with the backup member 28 (see FIG. 1).

The suction valve urging portion 34 includes a leaf spring piece 36 provided on the cylindrical portion 32. The base end portion 36 a of the leaf spring piece 36 is bent toward the radially outer side of the cylindrical portion 32. The central portion 36 c is curved in an arc shape and protrudes radially outward from the outer periphery of the cylindrical portion 32. And the front-end | tip part 36b is located in the radial inside of the cylindrical part 32 rather than the center part 36c. In the suction valve biasing portion 34, the pressing force of the suction valve 4 against the ball valve body 4a against the seat surface 4b is set by adjusting the bending angle of the base end portion 36a.
The gap formed between the leaf spring piece 36 and the tubular portion 32 constitutes an oil passage 38 that communicates the inside and outside of the bottomed tubular member 25 in the pressure chamber 29 of the pump cylinder 21.

The pump cylinder 21 includes a piston 22, a seal 27, a backup member 28, a ball valve body 4 a, a bottomed cylindrical member 25, and a spherical plug 24 in order from the eccentric cam rotor chamber 26 toward the axial positive direction. The pump cylinder 21 is assembled from the 1a side. First, the ball valve body 4a is inserted into the pump cylinder 21 and placed on the seat surface 4b. Subsequently, after the seal 27 and the backup member 28 are press-fitted into the piston 22, the piston 22 is assembled into the pump cylinder 21. Next, the bottomed cylindrical member 25 is assembled. Here, a part of the cylindrical portion 32 of the bottomed cylindrical member 25 is fixed to the inner peripheral surface of the pump cylinder 21 by welding. Finally, the spherical plug 24 is inserted to form the crimped portion 21a.

Next, the operation of the piston pump P will be described.
When the motor M is driven, the piston 22 acts on the first end portion 22a by the axial force in the positive axial direction acting on the second end portion 22b by the rotation of the eccentric cam rotor 23 and the spring force of the piston urging portion 33. By receiving the axial force in the negative axial direction, the pump cylinder 21 reciprocates in the axial direction. By this reciprocation, the volume of the pressure chamber 29 changes, and the pressure of the internal brake fluid fluctuates, whereby the suction valve 4 and the discharge valve 7 are selectively opened and closed, and the pump action is performed.

  Here, in the plunger pump described in Patent Document 1 described above, the seat surface of the intake valve is provided at the tip of the plunger. For this reason, the ball valve body of the suction valve and the suction spring that biases the ball valve body toward the seat surface are accommodated in a socket provided at the tip of the plunger. This socket is press-fitted into the tip of the plunger and is urged toward the eccentric cam rotor side by a return spring provided in the pressure chamber. When the eccentric cam rotor is driven, the socket moves axially together with the plunger.

  However, in the plunger pump described in Patent Document 1, the return spring and the suction spring are provided separately, and a socket for attaching the ball valve body of the suction valve and the suction spring to the tip of the plunger is required. There is a problem that the number of parts constituting the structure is large, and the number of assembling steps increases.

  Also, when assembling the ball valve body, suction spring and socket of the suction valve to the plunger, it is necessary to press-fit the socket into the plunger tip after setting the ball valve body and suction spring in the socket. Management items (suction spring stroke and preload, tightening allowance at press-fitting, etc.) are required.

  On the other hand, in the piston pump P of the first embodiment, the suction oil passage 1b is provided in the axial direction of the pump cylinder 21, the return spring disposed coaxially with the pump cylinder 21 and the axial direction of the pump cylinder 21. The suction spring to be disposed was integrated with the bottomed cylindrical member 25.

  For this reason, with respect to the plunger pump described in Patent Document 1, the same function can be realized with a smaller number of parts. In addition, the bottomed cylindrical member 25 is inserted into the housing 1 at the time of assembly, and the assembly is completed simply by fixing a part of the cylindrical portion 32 to the housing 1, so that the suction valve is provided at the first end 22a of the piston 22. There is no need to press-fit a socket or the like for providing the socket. Furthermore, the number of management items can be reduced by reducing the number of parts and simplifying the assembly process.

Next, the effect of the piston pump P of Example 1 is demonstrated.
In the first embodiment, a suction valve 4 that sucks in brake fluid, a discharge valve 7 that discharges brake fluid, a suction spring that biases the ball valve body 4a of the suction valve 4 in the valve closing direction, and a shaft in the housing 1 are provided. In a piston pump P having a piston 22 that reciprocates in a direction, a motor M and an eccentric cam rotor 23 that drive the piston 22, and a return spring that biases the piston 22 toward the eccentric cam rotor 23, a return spring and a suction spring Were integrally formed. Thereby, reduction of a number of parts and simplification of an assembly man-hour can be aimed at.

  In the first embodiment, a bottomed cylindrical member 25 is accommodated in a pump cylinder 21 formed in the housing 1, and the bottomed cylindrical member 25 has a piston urging portion 33 as a return spring at a bottom portion 31. Since the suction valve biasing portion 34 as the suction spring is provided in the shape portion 32, a configuration in which the return spring and the suction spring are integrally formed can be realized with a simple configuration using the bottomed cylindrical member 25.

  In the first embodiment, the brake fluid is sucked and reciprocated in the axial direction by the eccentric cam rotor 23 in the suction valve 4 having the ball valve body 4a biased to the seat surface 4b and the pump cylinder 21 formed in the housing 1. The bottomed cylindrical member having the piston 22 biased toward the eccentric cam rotor 23, the bottom 31 and the cylindrical portion 32 and accommodated in the pump cylinder 21 with the bottom 31 opposed to the axial direction of the piston 22 The bottomed cylindrical member 25 has a piston urging portion 33 for urging the piston 22 toward the eccentric cam rotor 23 at the bottom portion 31, and a ball valve body of the suction valve 4 at the cylindrical portion 32. There is a suction valve urging portion 34 that urges 4a toward the seat surface 4b. Thereby, reduction of a number of parts and simplification of an assembly process can be aimed at.

  In the first embodiment, in the piston pump P for a brake device that sucks in the brake fluid supplied from the reservoir 14 storing the decompressed brake fluid to the wheel cylinder W / C, the inside of the pump cylinder 21 formed in the housing 1 is axially moved. A piston 22 that reciprocates, an eccentric cam rotor 23 that drives the piston 22, a return spring that biases the piston 22 toward the eccentric cam rotor 23, and brake fluid is sucked into the pump cylinder 21 and biased to the seat surface 4b. The bottomed cylindrical member 25 which has the suction valve 4 having the ball valve body 4a, the bottom portion 31 and the cylindrical portion 32, and is accommodated in the pump cylinder 21 with the bottom portion 31 facing the axial direction of the piston 22. The bottomed cylindrical member 25 has a piston urging portion 33 that urges the piston 22 toward the eccentric cam rotor 23 on the bottom portion 31. In addition, the cylindrical portion 32 has a suction valve biasing portion 34 for biasing the ball valve body 4a of the suction valve 4 toward the seat surface 4b. Thereby, reduction of a number of parts and simplification of an assembly process can be aimed at.

  In the first embodiment, the suction valve 4 is provided in the direction perpendicular to the axis of the piston 22. In the plunger pump described in Patent Document 1, since the suction valve is provided at the tip of the plunger, the plunger pump has to be elongated in the axial direction, leading to an increase in the size of the housing. On the other hand, since the axial length of the piston pump P can be suppressed by disposing the intake valve 4 in the direction perpendicular to the axis of the piston 22, it is possible to improve the onboard performance by making the housing 1 compact.

  In Example 1, the bottomed cylindrical member 25 was fixed to the housing 1 by welding a part of the outer peripheral surface of the cylindrical portion 32 to the inner peripheral surface of the pump cylinder 21. Here, when the bottomed cylindrical member 25 is not fixed to the housing 1, the bottomed cylindrical member is caused by the elastic deformation of the leaf spring piece 35 of the piston biasing portion 33 or the leaf spring piece 36 of the suction valve biasing portion 34. 25 axial directions and positions around the axial direction change. For this reason, the preload of the piston urging portion 33 and the suction valve urging portion 34 may deviate from the installation value. On the other hand, in the first embodiment, the leaf spring pieces 35 and 36 can be fixed at the initial position, and the preload can be maintained at the set value.

  The bottomed tubular member 25 is in contact with the spherical plug 24 on the bottom 31 side of the tubular portion 32 and is in contact with the backup member 28 on the top 37 side. That is, since the bottomed tubular member 25 is sandwiched in the axial direction by the spherical plug 24 and the backup member 28, the bottomed tubular member 25 can be reliably prevented from moving in the axial direction.

  In the first embodiment, since the oil passage 38 that communicates the inside and the outside of the tubular portion 32 is provided in the tubular portion 32, the pressure chamber 29 and the suction oil are covered with the tubular portion 32. The communication state between the passage 1b and the pressure chamber 29 and the discharge oil passage 1c can be secured, and the pump function is not hindered. Furthermore, in the first embodiment, since the oil passage 38 is a gap formed between the tubular portion 32 and the suction valve urging portion 34, a process of forming an oil passage separately in the tubular portion 32 is unnecessary. The process can be simplified.

[Example 2]
FIG. 4 is a front view (a) and a partial side sectional view (b) showing the configuration of the bottomed tubular member 41 of the second embodiment. The bottomed tubular member 41 of the second embodiment A coil spring 42 is provided as the piston urging portion 33. The coil spring 42 is formed in a spiral shape in which the radius of curvature gradually decreases from the base end portion 42a to the tip end portion 42b, and rises spirally from the bottom portion 31 to the top portion 37 side. Other configurations are the same as those in the first embodiment, and thus description thereof is omitted.

  Thus, even when the piston urging portion 33 of the bottomed tubular member 41 is the coil spring 42, the same operational effects as those of the first embodiment can be obtained.

Example 3
The third embodiment is an example in which the piston pump P of the first embodiment is applied to a brake device for a two-wheeled vehicle.
FIG. 5 is a hydraulic circuit diagram of the brake device of the third embodiment.

  The brake device according to the third embodiment includes two systems, an R (Rear) system and an F (Front) system. A rear wheel wheel cylinder W / C (Rear) is connected to the R system, and a front wheel cylinder W / C (Front) is connected to the F system. In the hydraulic circuit of FIG. 3, the same reference numerals are given to the same components as those constituting the hydraulic circuit shown in FIG. 1, and P is replaced by R and S is replaced by F.

  In a two-wheeled vehicle, the installation space of the brake device is more limited than in a four-wheeled vehicle. Therefore, by applying the piston pump P in which the return spring and the suction spring are integrated by the bottomed cylindrical member 25, the onboard performance can be improved.

(Other examples)
As mentioned above, although the form for implementing this invention was demonstrated based on each Example, the specific structure of this invention is not limited to the structure shown in each Example, The summary of invention is shown. Design changes and the like within a range that does not deviate are also included in the present invention.

P piston pump
W / C Wheel cylinder 1 Housing 14 Reservoir 21 Pump cylinder 22 Piston 23 Eccentric cam rotor 25 Bottomed cylindrical member 26 Eccentric cam rotor chamber 27 Seal 28 Backup member 41 Bottomed cylindrical member

Claims (2)

A housing having a passage formed therein;
A reservoir for storing hydraulic fluid flowing from the wheel cylinder;
A piston pump comprising a piston for recirculating the hydraulic fluid stored in the reservoir to the master cylinder side;
A pump cylinder formed in the housing and containing the piston;
An eccentric cam rotor chamber formed through the pump cylinder and accommodating an eccentric cam rotor for driving the piston;
A seal assembled in the pump cylinder, in contact with the wall in the pump cylinder and the outer periphery of the piston, and sealing the pump cylinder and the eccentric cam rotor chamber;
A backup member that is assembled in the pump cylinder and performs positioning in the axial direction of the seal in a state having a predetermined tightening margin with respect to the outer periphery of the piston ;
A bottomed cylindrical member fixed to the housing and in contact with the backup member;
A brake device comprising: The brake device according to claim 1, wherein
The piston has a cylindrical shape, and forms a suction oil passage communicating with the pump cylinder in the housing;
A brake device comprising a suction valve disposed in the suction oil passage.

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