CN219428104U

CN219428104U - Brake master cylinder

Info

Publication number: CN219428104U
Application number: CN202320143305.2U
Authority: CN
Inventors: 梁栋; 游廷海; 包淑芬
Original assignee: Chery Automobile Co Ltd
Current assignee: Chery Automobile Co Ltd
Priority date: 2023-02-07
Filing date: 2023-02-07
Publication date: 2023-07-28
Anticipated expiration: 2033-02-07

Abstract

The utility model aims to provide a brake master cylinder capable of reducing pedal return abnormal sound under an automatic parking working condition, which comprises a cylinder body, wherein a first piston and a second piston which reciprocate are arranged in the cylinder body, the inner cavity of the cylinder body is divided into a first hydraulic cavity and a second hydraulic cavity by the second piston, a first oil inlet hole and a second oil inlet hole which are communicated with the inside and the outside are respectively formed in the cylinder body corresponding to the first hydraulic cavity and the second hydraulic cavity, and an oil return channel which is communicated with the inside and the outside is additionally arranged on the cylinder body corresponding to the second hydraulic cavity. According to the scheme, the oil return channel is additionally arranged in the second hydraulic cavity of the brake master cylinder, so that brake fluid can be rapidly supplemented from the oil return channel and the second oil inlet hole when the first piston returns, vacuum during returning of the first piston is reduced, separation is not generated when the two pistons return, and impact abnormal sound is reduced.

Description

Brake master cylinder

Technical Field

The utility model relates to the technical field of automobile braking systems, in particular to a braking master cylinder.

Background

In a hydraulic brake system of a vehicle, a master cylinder is used to generate hydraulic pressure and transmit the generated hydraulic pressure to a caliper brake mounted at each wheel. Fig. 1 shows a structure of a general brake master cylinder, which includes a first piston 3 and a second piston 4, the first piston 3 and the second piston 4 being installed in a cylinder bore 2 of a cylinder body 1 to be movable back and forth. The interior of the cylinder bore 2 is divided into a first hydraulic chamber 5 and a second hydraulic chamber 6 by a second piston 4. When the first piston 3 of the master cylinder moves forward, the first piston 3 applies pressure to the oil in the first hydraulic chamber 5, and then the oil pressure in the first hydraulic chamber 5 presses the second piston 4. Then, the second piston 4 applies pressure to the oil in the second hydraulic chamber 6. Thereby, the oil in the first hydraulic chamber 5 is supplied to the caliper brake (not shown) of the two wheels via the first oil hole 7, and the oil in the second hydraulic chamber 6 is supplied to the caliper brake of the other two wheels via the second oil hole 8. When the automatic parking function is opened, after a part of brake fluid in the brake system is locked on the ESC controller, the brake fluid cannot be timely supplemented from the second oil hole 8 when the brake pedal is quickly returned, so that vacuum is generated in the main cylinder cavity, the negative pressure in the second hydraulic cavity 6 is larger than that in the first hydraulic cavity 5, the second piston 4 is not synchronous with the return of the first piston 3, impact is generated, vibration is generated with the oil pipe, and impact abnormal sound occurs.

Disclosure of Invention

The utility model aims to provide a brake master cylinder capable of reducing abnormal noise caused by pedal return under an automatic parking working condition.

In order to achieve the above purpose, the technical scheme adopted by the utility model is as follows: the utility model provides a brake master cylinder, includes the cylinder body, is provided with reciprocating motion's first piston and second piston in the cylinder body, and the cylinder body inner chamber is divided into first hydraulic pressure chamber and second hydraulic pressure chamber by the second piston, has offered respectively the inside and outside first inlet port of intercommunication and second inlet port on the cylinder body that first hydraulic pressure chamber and second hydraulic pressure chamber correspond, has still add the inside and outside oil return passageway of intercommunication on the cylinder body that the second hydraulic pressure chamber corresponds.

According to the scheme, the oil return channel is additionally arranged in the second hydraulic cavity of the brake master cylinder, so that brake fluid can be rapidly supplemented from the oil return channel and the second oil inlet hole when the first piston returns, vacuum during returning of the first piston is reduced, separation is not generated when the two pistons return, and impact abnormal sound is reduced.

Drawings

FIG. 1 is a schematic diagram of a prior art master cylinder;

FIG. 2 is a schematic diagram of a brake master cylinder according to the present utility model;

fig. 3 is a schematic view of the cylinder block in fig. 2.

Detailed Description

As shown in fig. 2 and 3, a brake master cylinder comprises a cylinder body 10, a first piston 20 and a second piston 30 which reciprocate are arranged in the cylinder body 10, the inner cavity of the cylinder body 10 is divided into a first hydraulic cavity a and a second hydraulic cavity B by the second piston 30, a first oil inlet hole 11 and a second oil inlet hole 12 which are communicated with the inside and the outside are respectively formed in the cylinder body 10 corresponding to the first hydraulic cavity a and the second hydraulic cavity B, and an oil return channel 13 which is communicated with the inside and the outside is additionally arranged on the cylinder body 10 corresponding to the second hydraulic cavity B. The oil return channel 13 is added in the second hydraulic cavity B of the brake master cylinder, so that brake fluid can be rapidly supplemented from the oil return channel 13 and the second oil inlet hole 12 when the first piston 20 returns to reduce vacuum when the first piston 20 returns to the original position, and separation is not generated when the two pistons return to reduce impact abnormal sound.

In order to ensure timely oil return and avoid interference with oil discharge, the oil return channel 13 is arranged adjacent to the second oil inlet hole 12, a one-way valve is arranged in the oil return channel 13, the conduction direction of the one-way valve is from the outside of the cylinder body 10 to the inside, namely, the one-way valve is opened and acted only when the oil return channel 13 returns oil, and is in a closed state when oil is discharged.

Two expansion parts 14 are arranged on the cylinder body 10 corresponding to the second hydraulic cavity B along the axial direction at intervals, and the second oil inlet hole 12 and the oil return channel 13 are arranged on cylinder walls corresponding to the two expansion parts 14, so that the oil can enter and exit.

Further, the oil return passage 13 is provided at a side of the second oil inlet hole 12 remote from the first oil inlet hole 11.

In order to ensure the sealing effect, the inner walls of the cylinder body 10 at the two sides of the second oil inlet hole 12 and the oil return channel 13 are provided with sealing grooves 15, the inner walls of the cylinder body 10 at the two sides of the first oil inlet hole 11 are also provided with sealing grooves 15, an annular sealing ring 40 is arranged in the sealing grooves 15, and the annular sealing ring 40 is abutted against the outer walls of the first piston 20 and the second piston 30 to form sealing fit.

Claims

1. The utility model provides a brake master cylinder, includes cylinder body (10), is provided with reciprocating motion's first piston (20) and second piston (30) in cylinder body (10), and cylinder body (10) inner chamber is divided into first hydraulic pressure chamber (A) and second hydraulic pressure chamber (B) by second piston (30), has offered first inlet port (11) and second inlet port (12) inside and outside intercommunication respectively on cylinder body (10) that first hydraulic pressure chamber (A) and second hydraulic pressure chamber (B) correspond, its characterized in that: an oil return channel (13) communicated with the inside and the outside is additionally arranged on the cylinder body (10) corresponding to the second hydraulic cavity (B).

2. The master cylinder according to claim 1, wherein: the oil return channel (13) is arranged close to the second oil inlet hole (12), a one-way valve is arranged in the oil return channel (13), and the conduction direction of the one-way valve is from the outside of the cylinder body (10) to the inside.

3. The master cylinder according to claim 1, wherein: two expanding neck parts (14) are arranged on the cylinder body (10) corresponding to the second hydraulic cavity (B) along the axial direction at intervals, and the second oil inlet hole (12) and the oil return channel (13) are arranged on cylinder walls corresponding to the two expanding neck parts (14).

4. A master cylinder according to claim 3, wherein: the oil return channel (13) is arranged on one side of the second oil inlet hole (12) far away from the first oil inlet hole (11).

5. A master cylinder according to claim 3, wherein: a sealing groove (15) is formed in the inner wall of the cylinder body (10) on two sides of the second oil inlet hole (12) and the oil return channel (13), a sealing groove (15) is also formed in the inner wall of the cylinder body (10) on two sides of the first oil inlet hole (11), an annular sealing ring (40) is arranged in the sealing groove (15), and the annular sealing ring (40) is abutted against the outer walls of the first piston (20) and the second piston (30) to form sealing fit.