JPH11334565A - Brake fluid pressure control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brake fluid pressure control device provided with a reservoir eliminating apprehension of outside water and dust infiltrating in a gas chamber of the reservoir. SOLUTION: A reservoir 4 relieving a brake fluid in a wheel cylinder is provided by a seal structure in a brake fluid pressure control device main unit 1, a motor for a pump 3 driving a plunger pump 16 for returning the brake fluid flowing in this reservoir 4 to a master cylinder is mounted in the fluid pressure control device main unit 1 in a manner wherein the inside of a motor housing 23 is formed in a seal structure. The inside of the motor housing 23 and a gas chamber 9 isolated by a piston 5 in the reservoir 4 are connected by communication passages 20, 17, so as to relieve a pressure fluctuation of the gas chamber 9 according to sliding of the piston 5 in the reservoir 4 through these communication passages 20, 17 to a sealed space 33 in the motor housing 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a brake fluid pressure control device such as an antilock brake system (ABS) and a traction control system (ASR).

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 8-324406 is a conventional example of this type of brake fluid pressure control device. As described in this publication, in a brake fluid pressure control device, a reservoir for releasing brake fluid in a wheel cylinder is provided in a hole formed in an aluminum fluid pressure control device main body. However, the structure includes a piston that can slide in the hole, a spring that pushes back the piston, and a stopper that holds the spring in the hole, and the opening is covered with a resin cover. . In the reservoir, the back side of the piston is a liquid inflow chamber into which the brake fluid flows, and the front side is a gas chamber isolated by the piston from the liquid inflow chamber and communicating with the atmosphere. The communication of the gas chamber with the atmosphere is performed via a gap formed between the cover and the main body of the hydraulic pressure control device.

The operation of a conventional reservoir will be described. For example, when an ABS or the like is operated, the brake fluid repeatedly flows into and out of the fluid inflow chamber of the reservoir. And
This repetition involves an increase or decrease in the volume of the gas chamber due to the reciprocal sliding of the piston. The sliding of the piston, that is, the increase or decrease in the volume of the gas chamber, is made possible by the gas in the gas chamber coming in and out of the outside through the gap of the cover part, that is, breathing.

[0004]

SUMMARY OF THE INVENTION However, ABS
The reservoir breathes as described above at the time of operation, etc., but when breathing in (when the volume of the gas chamber increases due to the return of biston), the outside air is sucked into the gas chamber. As a result, water and dust in the air enter into the reservoir together with this suction, causing rust and foreign matter to be caught on the sliding surface of the piston, and the sliding of the piston cannot be performed smoothly. There is a problem that the performance of the control device is reduced. The problem was particularly remarkable in places where environmental conditions were poor in terms of water and dust.

[0005] It is an object of the present invention to provide a brake fluid pressure control device provided with a reservoir in which external water and dust do not enter the gas chamber of the reservoir.

[0006]

In order to achieve the above object, the invention according to claim 1 of the present application is characterized in that a reservoir for releasing brake fluid in a wheel cylinder is provided in a body of a hydraulic pressure control device in a sealed structure, and the reservoir is provided with the reservoir. A pump motor for driving a plunger pump for returning the brake fluid flowing into the master cylinder to the main body of the hydraulic pressure control device so that the motor housing has a sealed structure,
The inside of the motor housing communicates with a gas chamber isolated by a piston in the reservoir through a communication passage, and a pressure fluctuation in the gas chamber caused by sliding of the piston in the reservoir through the communication passage is reduced by the motor housing. A brake fluid pressure control device characterized in that the brake fluid pressure control device is made to escape to a sealed space inside. According to the present invention, the reservoir is sealed so as to be shielded from the atmosphere, and the gas chamber of the reservoir is connected to the inside of the motor housing also having the sealed structure via the communication passage. Therefore, since the air is shut off from the outside atmosphere by the sealing structure, there is no danger of inhaling outside moisture or dust even if the gas chamber of the reservoir breathes during the operation of the ABS or the like. At this time, since the inside of the motor housing has a large space in space, the breathing of the gas chamber, that is, the sliding of the piston can be performed smoothly and smoothly, and the pressure fluctuation of the gas chamber can be easily changed. It can escape to the inside sealed space.

According to a second aspect of the present invention, in the first aspect of the present invention, the sealing structure of the reservoir is such that an opening of the reservoir facing the outer surface of the fluid pressure control device main body is formed of an aluminum cap. It is characterized in that it is covered and a first gasket is interposed at the joint between the two. Since the reservoir opening is sealed by the aluminum cap and the first gasket, the sealing structure is simple and easy to manufacture.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the sealing structure of the motor housing includes an outer edge of a joint surface between the motor housing and the main body of the hydraulic control device. A second gasket is interposed in the portion, and a third gasket is interposed in a joint surface between a bolt seat for fixing the motor housing to the hydraulic pressure control device and the housing. And Such second gasket and third gasket
Since it is sealed with a gasket, the number of parts is small, the sealing structure is simple, and manufacturing is easy.

According to a fourth aspect of the present invention, in the first aspect of the present invention, a sealed structure is provided in the sealed space in the motor housing and the fluid pressure control device main body. A sealed space in the housing of the attached-ECU is communicated by utilizing a gap in the outer skin of the wire harness. The inside of the outer sheath of the wire harness accommodates a bundle of lead wires, but is not in a sealed state but has a gap, and the gap connects the inside of the outer jacket from one end to the other end. According to the present invention, the sealed space inside the motor housing is communicated with the sealed space inside the housing of the attached-ECU using the gap in the outer skin of the wire harness which is usually provided, so that the pressure fluctuation in the gas chamber is improved. The capacity of the sealed space, which is the escape destination, can be made larger and larger without increasing the number of parts.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a brake fluid pressure control device according to an embodiment of the present invention, in which a main portion of a reservoir portion is visible, FIG. 2 is a partially enlarged cross-sectional view of FIG. 1, and FIG. FIG. 4 is a cross-sectional view of a pump motor for driving a plunger pump in the control device. As shown in FIG. 3, the brake fluid pressure control device of the present embodiment includes a fluid pressure control device main body 1 having a reservoir, a plunger pump (brake fluid circulation pump), and the like built therein.
Attached-ECU2 containing solenoid valves and electronic components
And a pump motor 3 for driving the plunger pump.

The hydraulic pressure control device main body 1 is made of an aluminum material, and as shown in FIG. 1, a reservoir 4 is provided in a hole formed in the lower surface of the device main body 1. The reservoir 4 is for releasing brake fluid in a wheel cylinder (not shown). The piston 5 can slide in the hole, a spring 6 for pushing back the piston 5, and a reservoir stopper 7 for holding the spring 6 in the hole. And The piston 5 separates the brake fluid inflow chamber 8 at the back of the hole from the gas chamber 9 at the front. FIG. 1 shows the brake fluid inflow chamber 8.
Indicates an empty state, that is, a state in which no brake fluid flows. Reference numeral 10 denotes an O-ring for sealing, reference numeral 11 denotes a retaining ring for holding the reservoir stopper 7, and reference numeral 12 denotes an opening provided for the inspection of the reservoir stopper 7.

An aluminum cap 13 is press-fitted and fixed to the opening of the reservoir 4 so as to seal the inside of the hole. As shown in FIG. 2 in an enlarged manner, the sealing structure is provided on the joint surface around the cap 13 with the hydraulic pressure control device main body 1.
In this example, it is formed by interposing a first gasket 14 made of silicon. In FIG.
Reference numeral 5 denotes a groove for the retaining ring. Here, the sealing structure may be any structure as long as the opening of the reservoir 4 can be shielded from the atmosphere, and it is needless to say that the structure is not limited to a specific structure in relation to the purpose.

As shown in FIG. 1, a plunger pump 16 for returning the brake fluid escaping into the brake fluid inflow chamber 8 of the reservoir 4 to the master cylinder (not shown) is provided in the main body 1 of the hydraulic pressure control device. Is provided. Also,
As shown in FIG. 3, the hydraulic pressure control device main body 1 has a motor cam chamber 1 from the side opposite to the attached ECU 2.
A pump motor 3 for driving the plunger pump 16 is inserted into the motor cam chamber 17 by inserting the protruding end 25 of the motor shaft 18 into the motor cam chamber 17. That is, the distal end portion 19 of the plunger pump 16 and the motor shaft portion 18 of the pump motor 3 are connected in the motor cam chamber 17 so that power can be transmitted. Since this connection structure uses a known structure, FIG.
The illustration of the motor shaft portion 18 in the motor cam chamber 17 is omitted to avoid congestion in the figure, and in FIG. The description is omitted for the same reason.

As shown in FIG. 1, the gas chamber 9 of the reservoir 4 is communicated with the motor cam chamber 17 through a communication hole 20 formed in the hydraulic pressure control device main body 1 according to the present invention. ing. In this case, the communication hole 20 is formed in the control device main body 1 as shown in FIG.
Because it communicates with the outside on the bottom and right side of the
Sealing balls 21 and 22 are press-fitted into those portions to secure a sealing structure.

As shown in FIGS. 3 and 4, the pump motor 3 has an end cover 24 located at one end of the motor housing 23 and having the same size as the inside diameter of the entrance portion of the motor cam chamber 17. An end plate 26 having an outer diameter is integrally formed. When the end plate 26 is inserted into the entrance of the motor cam chamber 17, the end cover 24 is firmly in contact with the facing surface of the hydraulic pressure control device main body 1 and is fixed. Here, the motor housing 23 is attached to the hydraulic pressure control device main body 1 so as to form a sealed structure. In the present embodiment, this sealing structure is provided at the outer edge of the joint surface between the motor housing 23 and the hydraulic pressure control device main body 1 as shown in FIGS. 4 and 5 (viewed in the direction of arrow V in FIG. 4). , A second gasket 27 made of silicon is interposed,
Further, as shown in FIGS. 6 (viewed in the direction of arrow VI in FIG. 4) and FIG. 7, a seat portion 29 of a bolt 28 for firmly fixing the motor housing 23 to the hydraulic pressure control device 1 and the housing 23 are provided. Are formed by interposing a third gasket 30 on the joining surface of the first and second gaskets. That is, the portion of the motor housing 23 communicating with the outside is sealed by the second gasket 27 and the third gasket 30, so that the motor housing 23 is formed in a sealed structure.

As shown in FIG. 3, the motor cam chamber 17 is provided with the projecting cover 26 of the motor housing 23.
Through a gap 31 between the outer surface and the outer surface of the end cover 24 isolated from the outside by the second gasket 27, the gap is communicated with a gap between the outer surface of the hydraulic pressure control device main body 1 and
The protruding cover 26 communicates with a sealed space 33 in the motor housing 23 through a through hole 32 formed in the motor cover 23. As is clear from the above description, the motor housing 2
In the present embodiment, a communication path for communicating the sealed space 33 in the inside 3 and the gas chamber 9 as a sealed space in the reservoir 4 is formed by the communication hole 20, the motor cam chamber 17, the gap 31 and the through hole 32. It is configured. Then, pressure fluctuation of the gas chamber 9 caused by sliding of the piston 5 in the reservoir 4 having the sealed structure is released to the sealed space 33 in the motor housing 23 through the communication passage.

Further, the pump motor 3 and the attached-ECU 2 which is provided on the fluid pressure control device main body 1 in a sealed structure are electrically connected via a wire harness 34. In the form, the sealed space 33 in the motor housing 23 and the attached-ECU
A sealed space (not shown) in the second housing 35 is communicated with the outside by using a gap (not shown) in the outer skin of the wire harness 34.

Next, the operation of the above embodiment will be described. According to the present embodiment, the reservoir 4 has a sealed structure and is shielded from the atmosphere, and the gas chamber 9 of the reservoir 4 is further connected to the communication path 20.
The motor housing 2 also has a hermetically sealed structure through a communication path including the motor cam chamber 17, the gap 31 and the through hole 32.
3 inside. Therefore, since the sealed structure is shut off from the outside atmosphere, even if the inside of the gas chamber 9 of the reservoir 4 breathes during the operation of the ABS or the like, there is no danger of sucking outside moisture or dust. In addition, since the inside of the motor housing 23 has a large space in space, the breathing of the gas chamber 9, that is, the sliding of the piston 5 can be smoothly and smoothly performed, and the pressure fluctuation of the gas chamber 9 can be easily changed. It can escape to the sealed space 33 inside the motor housing 23.

The one in which the opening of the reservoir 4 is sealed by the aluminum cap 13 and the first gasket 14 has a simple sealing structure and is easy to manufacture. Further, the sealing structure of the motor housing 23 is formed by interposing a second gasket 27 at the outer edge of the motor housing,
The third gasket 3 is provided on the seat 29 of the bolt 28.
In the case where the gasket is inserted with zero, only two gaskets 27 and 30 are sufficient, so that the number of parts is small, the sealing structure is simple, and the production is easy.

In the case where the sealed space 33 in the motor housing 23 and the sealed space in the housing 35 of the attached-ECU 2 communicate with each other by using a gap in the outer skin of the wire harness 34, a wire harness which is usually provided is used. The enclosed space 33 inside the motor housing 23 is attached to the attached ECU-ECU 2 using the space in the outer skin of the ECU 34.
Can be communicated with the sealed space in the housing 35, so that the capacity of the sealed space to which the pressure fluctuation in the gas chamber 9 escapes can be made larger and more marginal without increasing the number of parts.

[0021]

According to the present invention, the reservoir is hermetically sealed so that it is isolated from the atmosphere. Therefore, even when the gas chamber of the reservoir breathes during operation of the ABS or the like, there is no danger of inhaling external moisture or dust. And at that time, the inside of the motor housing
Since it has a large capacity in space, the breathing of the gas chamber can be performed smoothly and smoothly, and the pressure fluctuation of the gas chamber can be easily released to the sealed space inside the motor housing.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a brake fluid pressure control device according to an embodiment of the present invention, in which a main portion of a reservoir portion is visible.

FIG. 2 is a partially enlarged sectional view of FIG.

FIG. 3 is a side view, partly in section, illustrating a communication passage of the brake fluid pressure control device according to the present embodiment.

FIG. 4 is a sectional view of a pump motor that drives the plunger pump according to the present embodiment.

FIG. 5 is a view taken in the direction of the arrow V in FIG. 4;

FIG. 6 is a view taken in the direction of arrow VI in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydraulic pressure control device main body 2 Attached-ECU 3 Plunger pump 4 Reservoir 5 Piston 6 Spring 7 Reservoir stopper 8 Brake fluid inflow chamber 9 Gas chamber 13 Aluminum cap 14 First gasket 16 Plunger pump 17 Motor cam chamber 18 Motor shaft Reference Signs List 20 communication hole 23 motor housing 26 end plate 27 second gasket 28 bolt 29 seat 30 third gasket 31 gap 32 through hole 33 sealed space 34 wire harness 35 housing

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[Procedure amendment]

[Submission date] August 7, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Added

[Correction contents]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a brake fluid pressure control device according to an embodiment of the present invention, in which a main portion of a reservoir portion is visible.

FIG. 2 is a partially enlarged sectional view of FIG.

FIG. 3 is a side view, partly in section, illustrating a communication passage of the brake fluid pressure control device according to the present embodiment.

FIG. 4 is a sectional view of a pump motor that drives the plunger pump according to the present embodiment.

FIG. 5 is a view taken in the direction of the arrow V in FIG. 4;

FIG. 6 is a view taken in the direction of arrow VI in FIG. 4;

FIG. 7 is an enlarged side view of a bolt used in the present invention.

[Description of Signs] 1 Hydraulic pressure control device main body 2 Attached-ECU 3 Plunger pump 4 Reservoir 5 Piston 6 Spring 7 Reservoir stopper 8 Brake fluid inflow chamber 9 Gas chamber 13 Aluminum cap 14 First gasket 16 Plunger pump 17 Motor Cam chamber 18 Motor shaft 20 Communication hole 23 Motor housing 26 End plate 27 Second gasket 28 Bolt 29 Seat 30 Third gasket 31 Gap 32 Through hole 33 Sealed space 34 Wire harness 35 Housing

Claims (4)

[Claims] 1. A pump for driving a plunger pump for returning a brake fluid flowing into the reservoir to a master cylinder by providing a reservoir for releasing brake fluid in the wheel cylinder in a body of the hydraulic pressure control device. A motor is attached to the fluid pressure control device main body so that the inside of the motor housing has a sealed structure, and the inside of the motor housing and a gas chamber isolated by a piston in the reservoir are communicated through a communication passage. A pressure fluctuation in the gas chamber caused by sliding of a piston in the reservoir through a sealed space in the motor housing through the brake fluid pressure control device. 2. The sealing structure of the reservoir according to claim 1, wherein the opening of the reservoir facing the outer surface of the main body of the hydraulic pressure control device is covered with an aluminum cap, and a first gasket is interposed at a joint between the two. And a brake fluid pressure control device. 3. The sealing structure of the motor housing according to claim 1, wherein a second gasket is interposed at an outer edge of a joint surface between the motor housing and the main body of the hydraulic pressure control device, and the motor housing is sealed. A brake fluid pressure control device comprising a third gasket interposed between a joint portion between a seat portion of a bolt for fixing the fluid pressure control device and the housing. 4. A wire harness according to claim 1, wherein the sealed space in the motor housing and the sealed space in the housing of the attached-ECU which is provided in the hydraulic pressure control device body in a sealed structure. A brake fluid pressure control device characterized in that communication is made by utilizing a gap in an outer skin of the brake fluid.