CN201751623U

CN201751623U - Brake wheel cylinder for drum brake

Info

Publication number: CN201751623U
Application number: CN2010202616636U
Authority: CN
Inventors: 陈文全
Original assignee: CSG TRW Chassis Systems Co Ltd
Current assignee: CSG TRW Chassis Systems Co Ltd
Priority date: 2010-07-16
Filing date: 2010-07-16
Publication date: 2011-02-23
Anticipated expiration: 2020-07-16

Abstract

The utility model discloses a brake cylinder for a drum brake, comprising a brake wheel cylinder body, a sealing ring and a piston extending in the brake wheel cylinder body in a sliding fit manner, wherein one end of the piston, extending in the brake wheel cylinder body, is provided with a sealing ring installing ring groove in which the sealing ring is arranged; the sealing ring is in sealing fit with the brake wheel cylinder body to form a working chamber; the piston is made of high-strength engineering plastics, therefore, in use, as the heat insulation property of the engineering plastics is good, the gasification and emulsification of brake liquid are delayed, and the safety of a vehicle is effectively improved; the wear-resistant coupling property between the engineering plastic and metal is good, so that the wear between the piston and the brake wheel cylinder is reduced, and the service life of the brake is prolonged; and simultaneously, as the engineering plastic is easy to machine and low in price, the manufacturing cost of the brake wheel cylinder is greatly reduced.

Description

The drum brake wheel cylinder

Technical field

The utility model relates to the vehicle braked parts, particularly a kind of drum brake wheel cylinder.

Background technique

Break is one of pass heavy parts of vehicle, and it is directly connected to the Security of vehicle, because drum brake has advantage with low cost, is still adopted by many vehicles.

Piston in the existing drum brake wheel cylinder all is to select ferrous material for use, for antirust ability and the sealability that improves piston, the processing of also need turning blue of the working surface of piston, determined existing drum brake wheel cylinder to have following shortcoming thus: 1. because the braking principle of drum brake is to brake by the friction between brake shoe and the brake drum, in braking process, will inevitably produce heat, the thermal conductivity of metallic material is good, heat will be passed to active chamber by piston, cause the brake fluid temperature in the active chamber to raise, the gasification and the emulsification of brake fluid have been quickened, thereby cause vehicle braking performances to reduce, threaten vehicle safety; 2. the manufacturing of piston need be adopted the surface treatment process that turns blue, and pollutants such as the waste liquid that turns blue that is produced are unfavorable to environment; 3. owing to the problem of wear-resisting coupling between metallic piston and the metal wheel cylinder cylinder body, also cause being easy between the two producing wearing and tearing, the working life of having reduced break; 4. the piston of metallic material processing inconvenience, material and processing cost are higher.

At above-mentioned deficiency, need existing drum brake wheel cylinder is improved, make it overcome above-mentioned shortcoming, improve its Security, prolong its working life, reduce its manufacture cost.

The model utility content

In view of this, the utility model provides a kind of drum brake wheel cylinder, this wheel cylinder adopts high-strength engineering plastic made piston, utilize good, the characteristics such as anti-corrosion capability strong, low price of wear-resisting coupling between the good and metal of the thermal insulation of engineering plastic materials, delay the gasification and the emulsification of brake fluid, improve the Security of vehicle, reduce the wearing and tearing between piston and the Brake drum cylinder body, prolong the working life of break, and reduce manufacture cost.

Drum brake wheel cylinder of the present utility model comprises Brake drum cylinder body and piston, and described piston is made by engineering plastics.

Further, described drum brake wheel cylinder also comprises seal ring, described piston one end stretches into the Brake drum cylinder body, and the end that described piston stretches into the Brake drum cylinder body is provided with seal ring annular groove is installed, seal ring be installed on that seal ring is installed in the annular groove and with the Brake drum cylinder body formation active chamber that is sealed and matched;

Further, the cylindrical inoperative section of described piston is provided with deformation-compensated groove;

Further, the axial groove of described deformation-compensated groove for circumferentially being set up in parallel along piston;

Further, seal ring is installed the annular groove sidewall and with the periphery intersection that the Brake drum cylinder body cooperates fillet is set with piston on the described piston;

Further, described drum brake wheel cylinder also comprises annular dirt-proof boot, described wheel cylinder end of body is provided with dirt-proof boot the annular groove I is installed, dirt-proof boot is set on the described piston annular groove II is installed, described annular dirt-proof boot two ends embed dirt-proof boot respectively and install in annular groove I and the dirt-proof boot installation annular groove II.

The beneficial effect of model utility: drum brake wheel cylinder of the present utility model, comprise the Brake drum cylinder body, seal ring and stretch into piston in the Brake drum cylinder body in the mode that is slidingly matched, the end that described piston stretches into the wheel cylinder cylinder body is provided with seal ring installation annular groove, seal ring be installed on that seal ring is installed in the annular groove and with the Brake drum cylinder body formation active chamber that is sealed and matched, described piston is made by high-strength engineering plastic, during use, because the thermal insulation of engineering plastic materials is good, the gasification and the emulsification of brake fluid have been delayed, effectively improved vehicle safety, wear-resisting coupling between engineering plastic materials and the metal has well also reduced the wearing and tearing between piston and the wheel cylinder, improved the working life of break, simultaneously, engineering plastic materials is easy to processing, low-cost characteristics also make the manufacture cost of wheel cylinder reduce greatly.

Description of drawings

Below in conjunction with drawings and Examples the utility model is further described.

Fig. 1 is a structural representation of the present utility model;

Fig. 2 is the structure of piston schematic representation;

Fig. 3 is the A-A sectional view of Fig. 2.

Embodiment

Fig. 1 is a structural representation of the present utility model, Fig. 2 is the structure of piston schematic representation, Fig. 3 is the A-A sectional view of Fig. 2, as shown in the figure: the drum brake wheel cylinder of present embodiment, comprise Brake drum cylinder body 1, seal ring 2 and stretch into piston 3 in the Brake drum cylinder body 1 in the mode that is slidingly matched, the end that described piston 3 stretches into wheel cylinder cylinder body 1 is provided with seal ring installation annular groove 3a, seal ring 2 be installed on that seal ring is installed in the annular groove 3a and with the Brake drum cylinder body 1 formation active chamber that is sealed and matched, described piston 3 is made by high-strength engineering plastic, as polycarbonate (PC), polyamide etc., present embodiment adopts polycarbonate (PC), in the braking process, brake fluid with certain pressure enters active chamber, act on seal ring and produce certain thrust, the promotion piston moves, piston promotes to make the gap of brake shoe and brake drum to eliminate generation friction torque (brake shoe and brake drum do not draw) on accompanying drawing, thereby reach the effect of braking, because piston selects for use the less high-strength engineering plastic of thermal distortion to make, when satisfying performance requirements such as piston intensity, because the thermal insulation of engineering plastics is better, be passed to the heat of brake fluid when also having reduced braking, suppressed the temperature rise of brake fluid effectively, the gasification and the emulsification of brake fluid have been delayed, improved braking ability, thereby the Security of vehicle is improved; In addition, because engineering plastics and metal body have wear-resisting preferably coupling and the strong characteristics of anti-corrosion capability, thereby improved greatly reliability of products and life-span.

In the present embodiment, the cylindrical inoperative section of described piston 3 is provided with deformation-compensated groove 3b, in the inoperative section of piston deformation-compensated groove is set, and can effectively alleviate or eliminate the variation that piston external diameter takes place because of being heated, guarantee the guide function of piston, guarantee the stability of pistons work.

In the present embodiment, the axial groove of described deformation-compensated groove 3b for circumferentially being set up in parallel along piston 3 rationally is provided with compensating tank according to the stressing conditions of piston, can guarantee that the performances such as intensity of piston reach usage requirement.

In the present embodiment, seal ring is installed annular groove 3a sidewall and with the periphery intersection that Brake drum cylinder body 1 cooperates fillet 3c is set with piston 3 on the described piston 3, prevented the scuffing of the embedded wearing and tearing of seal ring in the braking process and piston effectively to Brake drum cylinder body endoporus, simultaneously, because piston material is engineering plastics, the quality of processing of fillet very easily guarantees.

In the present embodiment; described drum brake wheel cylinder also comprises annular dirt-proof boot 4; described Brake drum cylinder body 1 end is provided with dirt-proof boot annular groove I 1a is installed; dirt-proof boot is set on the described piston 3 annular groove II 3d is installed; described annular dirt-proof boot 4 two ends embed dirt-proof boot respectively and install in annular groove I 1a and the dirt-proof boot installation annular groove II 3d; dirt-proof boot plays the proofing dust and protecting effect to the pistons work section, and it is simple in structure, easy installation and removal.

Explanation is at last, above embodiment is only unrestricted in order to the explanation the technical solution of the utility model, although the utility model is had been described in detail with reference to preferred embodiment, those of ordinary skill in the art is to be understood that, can make amendment or be equal to replacement the technical solution of the utility model, and not breaking away from the aim and the scope of technical solutions of the utility model, it all should be encompassed in the middle of the claim scope of the present utility model.

Claims

1. a drum brake wheel cylinder comprises Brake drum cylinder body (1) and piston (3), and it is characterized in that: described piston (3) is made by engineering plastics.

2. drum brake wheel cylinder according to claim 1, it is characterized in that: also comprise seal ring (2), described piston (3) one ends stretch into Brake drum cylinder body (1), the end that described piston (3) stretches into Brake drum cylinder body (1) is provided with seal ring annular groove (3a) is installed, seal ring (2) be installed on that seal ring is installed in the annular groove (3a) and with Brake drum cylinder body (1) the formation active chamber that is sealed and matched.

3. drum brake wheel cylinder according to claim 2 is characterized in that: the cylindrical inoperative section of described piston (3) is provided with deformation-compensated groove (3b).

4. drum brake wheel cylinder according to claim 3 is characterized in that: the axial groove of described deformation-compensated groove (3b) for circumferentially being set up in parallel along piston (3).

5. drum brake wheel cylinder according to claim 4 is characterized in that: described piston (3) is gone up seal ring installation annular groove (3a) sidewall and with the periphery intersection that piston (3) cooperates with Brake drum cylinder body (1) fillet (3c) is set.

6. drum brake wheel cylinder according to claim 5, it is characterized in that: also comprise annular dirt-proof boot (4), described Brake drum cylinder body (1) end is provided with dirt-proof boot annular groove I (1a) is installed, dirt-proof boot is set on the described piston (3) annular groove II (3d) is installed, described annular dirt-proof boot (4) two ends embed dirt-proof boot respectively and install in annular groove I (1a) and the dirt-proof boot installation annular groove II (3d).