JPS6330853Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a dust cover for a ball joint.

BACKGROUND ART Conventionally, a so-called fitting type ball joint as shown in FIG. 1 has been known. That is, reference numeral 1 denotes a socket that is the base of the joint, and a spherical part is integrally formed at one end of a ball stud 2 in a chamber 1b of the socket 1 that communicates with an opening 1a formed in the upper end of the socket 1 in the figure. 2a is inserted, and the ball stud 2 is prevented from being pulled out in the axial direction via the support ring 3, and the ball stud 2 is rotated in the radial direction and predetermined swinging with the spherical part 2a as the base end. . Reference numeral 4 designates a dust cover made of a flexible material that is attached to prevent dust from entering the moving part, and is approximately bowl-shaped, and has a shaft hole 4a in its curved bottom into which the ball stud 2 is inserted. At the same time, the open end 4b in which the reinforcing ring 5 is embedded is fitted into the peripheral stepped portion 1c of the socket 1, and grease is sealed inside to smooth the movement of the ball stud 2. 6 is a connecting rod, 7 is a nut screwed onto the male screw at the other end of ball stud 2,
8 is a saucer, and 9 is a spring.

When assembling the ball joint configured as described above, especially when attaching the dust cover 4 to the socket 1, a cylindrical pushing jig 10 is used as shown in FIG. The reinforced open end 4b of the dust cover 4 is press-fitted into the peripheral stepped portion 1c of the socket 1, but if there are dimensional variations in the dust cover 4 or the socket 1 due to machining, the following problems will occur.

In other words, this dimensional variation causes variation in the press fit of the open end 4b, and if the press fit is insufficient, a partial gap will be created between the end face of the open end 4b and the peripheral step 1c of the socket 1, allowing dust and water to enter. Otherwise, the grease may leak. On the other hand, if the press-fit is too much, the open end 4b
Since the end face of the reinforcing ring 5 and the peripheral step part 1c are compressed between planes, and there is no escape for the former part 4b made of a flexible material, a concentrated load is applied to the reinforcing ring 5, causing deformation of the reinforcing ring 5 and damage to the socket 1. The detachment load may decrease, or the flexible material around the reinforcing ring 5 may be damaged.

In view of the above points, the present invention was devised for the purpose of eliminating the above-mentioned problems caused by dimensional variations in the processing of the dust cover.
In order to achieve this purpose, a reinforcing ring having a tapered support part is embedded in a state in which the end face of the open end and the outer diameter edge are close to each other, and a reinforcing ring is provided that has a tapered support part buried in the end face of the open end and the outer diameter edge thereof, and a part of the end face that faces the peripheral step part of the socket. It is an object of the present invention to provide a dust cover for a ball joint, characterized in that an annular projection is formed at a portion on the inner diameter side from the vicinity of the outer diameter edge of the support portion of the reinforcing ring.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 3 shows an enlarged view of the open end 4b of the dust cover 4 shown in FIGS. 1 and 2. , its end surface 4c and outer diameter edge 5b
A reinforcing ring 5 having a tapered supporting part 5a and a rising part 5c extending from the outer diameter edge 5b is embedded, and a reinforcing ring 5 is embedded in the end face 4c of the open end 4b, facing the peripheral step part 1c of the socket 1. And from the vicinity of the outer diameter edge 5b of the support portion 5a of the reinforcing ring 5 to the inner diameter side,
A single annular protrusion 4d coaxial with the open end 4b is integrally formed in the vertical direction in the figure, and the annular protrusion 4d
is brought into contact with the peripheral stepped portion 1c of the socket 1.

When this dust cover 4 is attached to the socket 1, when the stroke is set approximately at the center of the height of the annular projection 4d and press-fitted, the annular projection 4d is backed up to the reinforcing ring 5 over the entire circumference. The annular protrusion 4d is flexible and can absorb excessive press-fitting by deforming. is completed, reinforcing ring 5
No concentrated load is applied to the reinforcing ring 5, and problems such as deformation of the reinforcing ring 5 can be prevented.

Further, in the dust cover 4, the reinforcing ring 5 includes a tapered support portion 5a with the outer diameter edge 5b close to the end surface 4c of the dust cover 4, and the annular protrusion 4d extends from the vicinity of the outer diameter edge 5b toward the inner diameter side. It is formed in the area of Therefore, the closer the annular protrusion 4d is formed to the outer diameter edge 5b, the more strongly it is backed up against the support portion 5a and pressed against the peripheral step portion 1c of the socket 1, and the more it is backed up against the tapered support portion 5a. Since the dust cover 4 is pressed so that it is more likely to tilt in the inner diameter direction than the outer diameter direction over the entire circumference, even if the internal pressure of the dust cover 4 suddenly increases due to the operation of the ball joint, grease will not leak. can be suppressed particularly effectively.

As explained above, in the ball joint dust cover of the present invention, the annular protrusion formed on the open end face is backed up by the reinforcing ring and comes into pressure contact with the socket, which increases the adhesion force to the socket and improves the sealing performance. has been significantly improved, reliably preventing the intrusion of dust, etc. and leakage of grease, and
In particular, the annular protrusion is formed from near the outer diameter edge of the tapered support part of the reinforcing ring to the inner diameter side, and the structure is such that the support part strongly backs up from the vicinity and tilts in the inner diameter direction. Even if the internal pressure of the dust cover suddenly increases and the grease easily leaks, this can be adequately coped with, and the reinforcing ring can be prevented from being deformed or damaged due to excessive press-fitting into the socket. This makes it possible, and the practical effects of the present invention are extremely large.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional ball joint and a dust cover attached thereto, Fig. 2 is an explanatory diagram of the method of attaching the ball joint, and Fig. 3 is a schematic diagram showing a dust cover according to an embodiment of the present invention. FIG. 1...Socket, 1a...Opening, 1b...
Chamber, 1c...peripheral step, 2...ball stud,
2a...Spherical part, 4...Dust cover, 4a...
Shaft hole, 4b...open end, 4c...end face, 4d...
Annular projection, 5... Reinforcement ring, 5a... Support part, 5b
...Outer diameter edge, 5c...Rising portion, 10...Pushing jig.

Claims (1)

[Scope of utility model registration request] An open end 4 that fits into the peripheral step 1c of the socket 1
In the dust cover for a ball joint having a ball joint dust cover, the end surface 4 of the open end 4b is
The reinforcing ring 5 is provided with a tapered supporting portion 5a buried in a state in which the outer diameter edge 5b and the outer diameter edge 5b are in close proximity to each other. The outer diameter edge 5 of the support portion 5a of
A dust cover for a ball joint, characterized in that an annular projection 4d is formed at a portion on the inner diameter side from the vicinity of b.