KR200431946Y1 - Drum Brake Wheel Cylinder - Google Patents

Abstract

The present invention relates to a wheel cylinder of a drum brake, the inlet body and the cylinder body are integrally formed by extrusion molding, and by forming a fixing part for mounting to a predetermined tool for processing on one side of the inlet body, Provided is a wheel cylinder of a drum brake which is increased, the manufacturing process is simplified, the failure rate according to the integral manufacturing of the inlet body and the cylinder body is reduced, and the cutting by the machine tool is easily performed.

Drum brake, wheel cylinder, cylinder body, inlet body, fixture

Description

Drum Brake Wheel Cylinder

1 is an exploded perspective view of a drum brake generally used;

Figure 2 is a cross-sectional view of the wheel cylinder shown for explaining the operation of the general wheel cylinder,

3 is a cross-sectional view showing a wheel cylinder manufactured by drawing;

Figure 4 is a perspective view briefly showing the shape of the wheel cylinder body according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: drum brake 110: back plate

120: brake shoe 130: wheel cylinder

140: brake drum 150: brake lining

131: oil inlet 132: inlet body

133: cylinder body 134: piston cap

135: piston 136: rebound spring

230: wheel cylinder body 232: inlet body

233: cylinder body 234: piston cap seating groove

235: oil inlet 236: tap hole

237 fixing part 230a body base

The present invention relates to a wheel cylinder of a drum brake. More specifically, the inlet body and the cylinder body are integrally formed by extrusion molding, and by forming a fixing part for mounting to a predetermined tool for processing on one side of the inlet body, the rigidity is increased, the manufacturing process is simplified, and the work is performed. It is related with the wheel cylinder of the drum brake which is easy to cut by a machine.

In general, a vehicle is provided with a brake system for selectively decelerating the vehicle speed or stopping the vehicle body as needed while driving. Such a brake system generally uses frictional force, and converts the kinetic energy of the vehicle into thermal energy. Friction brakes are mainly used to release thermal energy into the atmosphere and to allow braking of the vehicle.

These friction brakes can be broadly classified into a foot brake for braking while driving and a parking brake for fixing the vehicle when parked. The main brake of the vehicle is a hydraulic brake. This is used. Foot brake is usually generated by the braking force by the friction force generated by close contact with the friction material, such as brake drums, wherein the close contact load to the friction material is configured in such a way that acts by the hydraulic pressure generated as the interior brake pedal of the vehicle is pressed.

1 is an exploded perspective view of a drum brake generally used.

As shown in FIG. 1, the drum brake 100 includes a brake shoe 120, a wheel cylinder 130, a brake drum 140, and a back plate 110.

The brake drum 140 and the back plate 110 are coupled to each other to form an inner space, and the wheel cylinder 130 and the brake shoe 120 are mounted in the inner space, and the brake shoe 120 has a lower back. The brake lining 150 is coupled to the plate 110 by a hinge pin and contacts the brake drum 140 to the outer circumferential surface thereof. The wheel cylinder 130 is mounted on the upper portion of the brake shoe 120, and the brake shoe 120 is rotated around the hinge pin by the wheel cylinder 130.

At this time, the brake drum 140 rotates integrally with the wheel, and the brake shoe 120 rotates around the hinge pin to contact the brake drum 140 provided on the outside and generate a frictional force to brake the wheel. .

Brake shoe 120 is rotated by the hydraulic pressure of the wheel cylinder 130, Figure 2 is a cross-sectional view of the wheel cylinder shown for explaining the operation of the general wheel cylinder.

An inlet body 132 is formed at the center of the cylinder body 133 to form an oil inlet 131 for receiving hydraulic pressure from a master cylinder (not shown). Pistons 135 are provided and two piston caps 134 are mounted on both outer ends thereof to prevent each piston 135 from being separated from the cylinder body 133. According to this structure, when oil is introduced through the oil inlet 131, the two pistons 135 are moved to both ends of the cylinder body 133 by hydraulic pressure, and the brake shoe 120 is pressed against the brake drum 140. When the hydraulic pressure is released, the two pistons 135 are returned to the center side of the cylinder body 133 by the rebound spring 136 and the compression of the brake shoe 120 is released.

The inlet body 132 and the cylinder body 133 of the wheel cylinder 130 is usually made of aluminum, mainly produced by the manufacturing method by casting. The production method by casting has a problem of low productivity and weak rigidity due to the enlargement of the production equipment and the separate cutting process, etc. In order to solve such a problem, a manufacturing method by drawing processing has recently been used.

It is sectional drawing which shows the wheel cylinder produced by drawing process.

As shown in FIG. 3, unlike the casting process, the inlet body 132 and the cylinder body 133 may not be integrally formed due to the shape of the product and the characteristics of the drawing molding process, and the cylinder body 133 having a pipe shape. It is manufactured by combining the inlet body 132 manufactured separately. In addition, after such coupling, cutting processing such as the oil inlet 131 is performed separately.

In the case of such drawing process, there is a problem in that a production process such as split fabrication and joining is increased, and the product defect rate of the joining portion is increased as partly manufactured without being formed integrally.

In addition, after the casting or drawing process, a cutting process such as an oil inlet 131 is performed separately. In the case of such a cutting process, that is, a lathe and a drilling process, the inlet body 132 and the cylinder body 133 are machined. Due to the shape of the product in the process of fixing to the machine there is a problem that the cutting process is difficult because it is not easy to fix to the machine tool.

Therefore, the present invention has been devised to solve this problem, by integrating the inlet body and the cylinder body through the extrusion process, by forming a fixing part for mounting to a predetermined tool for processing on one side of the inlet body, The object is to provide a wheel cylinder of a drum brake which increases rigidity, simplifies the manufacturing process and is easy to cut by machine tools.

In order to achieve the above object, the present invention provides a wheel cylinder of a drum brake including an inlet body, a cylinder body, a piston, and a piston cap, wherein the inlet body and the cylinder body are integrally formed through an extrusion molding process. Provided is a wheel cylinder of a drum brake.

In addition, a fixing part for mounting to a predetermined tool for processing is formed on one side of the inlet body, wherein the shape of the fixing part is preferably a groove having a “V” shaped cross section in the longitudinal direction of the cylinder body. .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are designated as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related known configuration or function may obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Figure 4 is a perspective view briefly showing the shape of the wheel cylinder body according to an embodiment of the present invention.

According to the present invention, the wheel cylinder body 230 in which the inlet body 232 and the cylinder body 233 are integrally formed by the extrusion molding process is manufactured, and the oil inlet after the wheel cylinder body 230 is manufactured through the extrusion molding process. Cutting processing such as 235 is performed.

Due to the process characteristics of the extrusion process, the vertical cross-sectional shape of the product should be the same in all sections along the extrusion direction, so that the vertical cross-sectional shape is constant as shown in FIG. 4 (a) by the extrusion process. Is formed. The body base 230a is formed as shown in FIG. 4B by cutting in accordance with a predetermined shape of the wheel cylinder body 230. In the state in which the outer shape of the predetermined dimension is completed as shown in (c) of FIG. 4, the oil inlet 235 and the like is processed to complete the wheel cylinder body 230.

The shape of the cylinder body 233 is a hollow cylindrical shape, and the piston cap seating grooves 234 for seating the piston cap are formed at both end portions of the outer circumferential surface, respectively. An inlet body 232 is formed at a central portion of the outer circumferential surface of the cylinder body 233, and an oil inlet 235 is formed at an upper surface of the inlet body 232 to communicate with the inside of the cylinder body 233. This structure is the same as described in the prior art. On the other hand, the upper surface of the inlet body 232 may be formed with a predetermined tap hole 236 for coupling other components, if necessary.

In addition, the wheel cylinder according to an embodiment of the present invention is fixed to one side of the inlet body 232 to fix the wheel cylinder body 230 to a predetermined tool and machine tool for cutting the wheel cylinder body 230 237 is preferably formed. As shown in FIG. 4, the fixing portion 237 has a groove having a cross-sectional shape having a “V” shape along the longitudinal direction of the cylinder body 233, and is formed during extrusion molding. It is desirable to be able to easily rest on the machine tool at the time of cutting 230. In addition, the shape of the fixing part 237 may be formed in various ways such as a "U" shape in addition to the "V" shape of the cross-sectional shape.

On the other hand, the wheel cylinder of such a structure is mounted to the drum brake, and other shapes and operating principles are the same as described in the prior art in addition to the structure described above, detailed description thereof will be omitted.

Therefore, as described above, the wheel cylinder according to the present invention manufactured by the extrusion molding process has improved tissue density and increased rigidity, and the inlet body 232 and the cylinder body 233 are integrally formed to produce a manufacturing process. This is a wheel cylinder in the form of a simplified and reduced product defect rate. In addition, since the fixing part 237 for cutting is formed in the inlet body 232 during the extrusion molding process, the cutting process is easy, and various tap holes 236 for the assembly of other parts may be processed according to the user's needs. This is a wheel cylinder of the easy form.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention belongs may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas falling within the scope of the present invention should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, the inlet body and the cylinder body of the drum brake wheel cylinder are integrally formed by extrusion molding, and by forming a fixing part for mounting to a predetermined tool for processing on one side of the inlet body, The rigidity of the wheel cylinder is increased, the manufacturing process is simplified, the failure rate of the wheel cylinder due to the integral production of the inlet body and the cylinder body is reduced, and the wheel cylinder cutting process by the machine tool is easily performed.

Claims (3)

In a wheel cylinder of a drum brake comprising an inlet body, a cylinder body, a piston and a piston cap, And the inlet body and the cylinder body are integrally formed through an extrusion molding process. The method of claim 1, Wheel cylinder of the drum brake, characterized in that the fixing portion for mounting to a predetermined tool for processing is formed on one side of the inlet body. The method of claim 2, The shape of the fixing portion is a wheel cylinder of the drum brake, characterized in that the groove of the V-shaped cross-sectional shape is formed in the longitudinal direction of the cylinder body.

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