JPH0135979Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a retainer for a sealing member, and is provided to maintain airtightness at a portion where a push rod of a brake booster passes through a hole in a front shell, for example. The present invention relates to a retainer that prevents a seal member from coming off.

[Prior art]

In a brake booster, generally, a cylindrical recess is provided in the center of the front wall of the front shell and projects into the housing, and a push rod passes through a hole formed in the bottom wall of this recess. . In order to maintain airtightness between the push rod and the housing, a sealing member is inserted into the cylindrical recess, and an annular retainer is press-fitted from the outside of the sealing member to prevent the sealing member from falling out. are doing.

Conventionally, such a retainer for a sealing member has a ring-shaped flat part 1 that comes into contact with the sealing member, and an inclined part that is bent at equal intervals in the circumferential direction around this flat part 1, as shown in FIG. A device equipped with toothed portions 2 was used. However, although a retainer with this shape can fulfill its function if a spring steel plate is used, it has the disadvantage that it easily falls off when a mild steel plate is used to reduce costs. . Therefore, as shown in FIG. 3, a retainer has been proposed that has a cylindrical wall part 3 that is bent at right angles to the annular flat part 1 over the entire circumference of the annular flat part 1. However, in the case of a retainer of this shape, it is necessary to strictly control its external dimensions in order to press fit into the cylindrical recess of the housing, and furthermore, the other shell to be press fit is a pressed product. Because of the rough dimensions, there was a drawback that both the press-in load and the pull-out load varied greatly.

[Summary of the idea]

The present invention was developed in view of the above points, and includes forming an annular sloped part on the outer periphery of the flat part that contacts the sealing member, and forming a ring-shaped sloped part on the outer periphery of the sloped part with a depth shorter than the width of the sloped part. By providing a plurality of notches, it is possible to provide a retainer for a sealing member that is stable in both press-fitting load and pull-out load even when a general steel plate is used and the external dimensions are made rough.

[Example of idea]

Hereinafter, the present invention will be explained based on illustrated embodiments. FIGS. 1A and 1B show a retainer for a sealing member according to an embodiment of the present invention. It has an inclined part 4 which is bent toward the right side in FIG. A plurality of recesses 5 are formed at equal intervals in the circumferential direction. Incidentally, it is preferable that the inclination angle θ of the above-mentioned inclined portion 4 is 60° or more.

The retainer having the above structure is press-fitted into the cylindrical recess of the housing from the outside of the seal member to prevent the seal member from coming off. Since it is bent over the entire length, the rigidity is improved, and since the recess 5 is formed with a depth l shorter than the width L of the inclined part 4, even if the external dimensions are rough, there is no press-fitting load or pull-out load. Stable together. As a result, it becomes possible to use inexpensive general steel plates, and costs can be reduced.

Note that the shape of the recess 5 is not limited to the above-mentioned arc shape, but can be made into various shapes such as a rectangle and a trapezoid. Furthermore, the positions of the recesses 5 do not necessarily have to be equidistant in the circumferential direction.

[Effect of idea]

As described above, according to the present invention, it is possible to stabilize the press-in load and pull-out load of the retainer, and to reduce costs.

[Brief explanation of the drawing]

Figures 1A and 1B show an embodiment of the present invention, Figure A is a longitudinal sectional view, Figure B is a plan view, Figures 2A and 3A and 3B are conventional retainers, and each Figure A is a longitudinal sectional view, and Figure B is a plan view. 1... Flat part, 4... Inclined part, 5... Concave part, L
... Width of the slope, l ... Depth of the recess.

Claims (1)

[Scope of utility model registration request] A flat part that comes into contact with the sealing member, an annular sloped part bent around the outer periphery of the flat part, and a plurality of notches cut out to a depth shorter than the width of the sloped part on the outer peripheral edge of the sloped part. A retainer for a seal member, the retainer having a concave portion and press-fit into the cylinder from outside of the seal member disposed in the cylinder to hold the seal member.