JPH0633259Y2 - Gasket dropout prevention structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a gasket used for sealing a cover member, and more specifically, a gasket holder for preventing the gasket from falling out of a mounting groove of the cover member. Regarding the structure.

[Prior Art] Conventionally, as a structure for preventing the gasket from coming off from the gasket mounting groove at the time of assembling the cover member, a description will be given with reference to the drawings. As shown in Japanese Utility Model Publication No. 47-40192 shown in FIG. A convex surface 4 projecting a little larger than the width of the annular groove 2 for mounting the gasket 3 is provided on both sides or one side surface of the annular groove at appropriate intervals, and the convex surface 4 is press-fitted into the annular groove 2 and has a repulsive resistance generated therefrom. The entire gasket 3 was prevented from falling off.

[Problems to be Solved by the Invention] However, in the structure in which the convex surface 4 is partially provided on the side surface of the gasket 3 as described above, the convex surface 4 is compressed and deformed and mounted in the annular groove 2 of the cover member A. Therefore, the mounting workability is extremely poor, and since local deformation is caused because it is partially deformed, this means that the sealing surface pressure on the gasket 3 peripheral surface is not constant and stable during tightening from the viewpoint of sealing performance. It appears as a big defect that the sealing force cannot be expected.

The present invention has been made in view of these drawbacks, and an object of the present invention is to provide a gasket drop-out prevention structure which is excellent in fixing property without local deformation and excellent mountability.

[Means for Solving the Problems] The present invention provides a sealing structure in which a gasket 3 is attached to an annular groove 2 of a sealing surface 1 of a cover member A for sealing as shown in FIG. In the gasket falling prevention structure for preventing falling off from the annular groove 2 during assembly of A; the gasket 3 is formed in substantially the same shape as the annular groove 2, but the corner portion of the gasket 3 is formed as shown in FIG. Alternatively, the R-part dimension a formed in the bent portion
It is characterized in that it is formed to be longer than the R portion size b of.

[Operation] The present invention has the above-described structure and performs many operations as described below.

As shown in FIG. 1, the gasket 3 of the present invention has a bent portion formed longer than the bent portion of the cover member A. Therefore, when the gasket 3 is mounted in the annular groove 2 of the cover member A shown in FIG. A long R portion dimension a is in contact with the inner and outer peripheral walls of the annular groove 2 which does not fit exactly inside the annular groove 2 and is largely deformed and mounted. This deformation generates a restoring repulsive force in the gasket 3 made of an elastic body and makes a soft partial contact with the peripheral wall of the annular groove 2 to support the weight of the gasket 3 by itself and prevent the falling off against the downward force.

[Embodiment] In carrying out the present invention, a cover member A having a bent portion is formed.
The R dimension and the R dimension of the gasket 3 do not need to be formed to have the same diameter, and they may be provided with different diameters with the R diameters of the two slightly shifted.

Further, the R part dimension a of the gasket 3 is set to the R part of the cover member A.
The location corresponding to the partial dimension b may be determined and arranged according to the required holding force, and it is not necessary to provide it at all locations of the curved portion.

[Advantage of the Invention] According to the present invention, since the gasket 3 is not formed with an extra additive, the gasket 3 can be mounted smoothly.
In addition, the work efficiency is high because they follow the shape of each other.

Since the width of the annular groove 2 of the cover member A and the thickness of the gasket 3 can be formed to have the same size around the entire circumference, the compression surface pressure is kept constant against the tightening pressure, and a very good sealing property is obtained. At this time, the gasket 3 does not receive any local load that promotes aging.

Further, in manufacturing the mold for forming the gasket 3,
Since there is no need to make a complicated engraving on the mold and it is sufficient to simply extend the R portion, there is an advantage that it can be formed at low cost.

[Brief description of drawings]

FIG. 1 is a partial plan view showing an embodiment of the gasket of the present invention. FIG. 2 is a partial bottom view of the cover member.
FIG. 3 is a partial plan view of a conventional gasket. A: cover member, a: gasket R dimension, b
...... R part dimension of annular groove 1 …… Seal surface, 2 …… annular groove, 3 …… Gasket, 4
...... Convex part

Claims (1)

[Scope of utility model registration request] 1. A gasket drop-off prevention structure for preventing a drop-out from the annular groove 2 in a sealing structure in which a gasket 3 is mounted in an annular groove 2 of a sealing surface 1 of a cover member A for sealing. A gasket 3 is formed in substantially the same shape as the annular groove 2, and an R portion dimension a formed at a corner or a bent portion of the gasket 3 is formed to be longer than an R portion dimension b of the annular groove 2. Has a gasket falling prevention structure.