JP2558795Y2 - Ball joint dust cover mounting structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust cover mounting structure for a ball joint.

[0002]

2. Description of the Related Art A ball joint generally comprises a ball stud, a synthetic resin ball seat for fitting and holding the spherical portion of the ball stud, and a socket for fitting the ball seat. A dust cover made of an elastic material such as rubber is attached between the outer periphery of the edge and the outer periphery of the shaft of the ball stud, and dust such as water or dust enters the sliding surface between the ball seat and the ball stud spherical portion from the outside. It is common to seal to prevent things from happening.

As shown in FIG. 2, for example, the dust cover A has a large-diameter fitting portion A1 fitted to a dust cover mounting portion B 'provided on the outer periphery near the opening edge of the socket B, and a ball stud. A small-diameter fitting portion A2 fitted on the shaft portion (tapered shaft portion) C 'of C at both ends, and a link member D is fitted and fixed on the shaft portion C', so that a small-diameter fitting is performed as shown by a chain line. The inner peripheral surface and the upper surface of the portion A2 are resiliently attached to the outer peripheral surface of the shaft portion C 'and the bottom surface of the link member D.

[0004]

The ball stud performs an oscillating motion with respect to the socket and a rotational motion about the axis of the ball stud. During the oscillating motion of the ball stud, the dust cover A The bellows portion A3 is deformed following the swinging motion, and during the rotation motion, the inner peripheral surface and the upper surface of the small diameter fitting portion A2 of the dust cover A are attached to the outer peripheral surface of the shaft portion C 'and the bottom surface of the link member D. On the other hand, it is necessary to prevent the dust cover A from sliding relatively and twisting. Accordingly, the respective elastic contact portions between the inner peripheral surface and the upper surface of the small-diameter fitting portion A2 and the shaft portion C 'and the bottom surface of the link member D must be not only seal surfaces but also surfaces suitable for sliding surfaces. In addition, the outer peripheral surface of the shaft portion C 'and the bottom surface of the link member D must be subjected to fairly precise machining so that the sealing performance is good and the small-diameter fitting portion A2 is slippery. have.

[0005] The present invention has as its main object to address the above conventional problems.

[0006]

The present invention provides a dust cover in which a tapered tube having a flange at its lower end is fitted to a tapered shaft portion of a ball stud, and the outer periphery of the tapered shaft portion of the ball stud is fitted. The upper surface of the small-diameter fitting portion elastically contacts the lower surface of the flange portion of the tapered pipe, and the outer peripheral surface of the tapered shaft portion where the inner peripheral surface of the small-diameter fitting portion of the dust cover elastically contacts the upper surface of the small-diameter fitting portion. The sealing surface is constituted by the lower surface of the flange portion of the tapered pipe.

[0007]

In the above, since the tapered tube is formed by press molding, the flange portion serving as the sealing surface is sufficiently smooth and does not need to be machined, and in some cases, it becomes the sealing surface. For example, it is easy to make the flange portion of the tapered tube more slippery by coating with a synthetic resin material, so that it is not necessary to carefully machine the bottom surface of the link member as in the conventional case. Cost can be reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 1 denotes a ball stud, 2 denotes a ball seat made of a synthetic resin for fitting and holding the spherical portion 1a of the ball stud 1, and 3 denotes a socket for press-fitting the ball seat 2; The ball seat 2 fitted with the spherical portion 1a is pressed into the socket 3 from the lower opening of the socket 3 and the end plate 4 is fixed to the lower opening of the socket 3 by caulking.

Reference numeral 5 denotes a dust cover made of an elastic material such as rubber.
A large-diameter fitting portion 51 fitted to the dust cover mounting portion 3b provided on the outer periphery and a small-diameter fitting portion 52 fitted to the outer periphery of the shaft portion of the ball stud 1 are attached at both ends to a large-diameter fitting. A press-fit ring 51a is buried in the portion 51, and a reinforcing ring 52a is buried in the small-diameter fitting portion 52. The structure of the dust cover 5 is the same as the conventional one.

Reference numeral 6 denotes a link member. The link member 6 is formed by fitting a tapered shaft portion 1b of the ball stud 1 into a tapered hole 6a and screwing a nut 7 into a threaded portion 1c at the tip of the tapered shaft portion 1b. Stud 1
In FIG. 1, a tapered tube 8 is interposed between the tapered shaft portion 1b and the tapered hole 6a, and a flange portion 8a provided at a large-diameter end of the tapered tube 8 has a tapered shaft portion. The upper surface of the small-diameter fitting portion 52 fitted into the small-diameter fitting portion 1b makes elastic contact with the inner peripheral surface of the small-diameter fitting portion 52 and the tapered shaft portion 1b, and the upper surface of the small-diameter fitting portion 52 and the flange of the tapered tube 8. The elastic contact portion with the portion 8a serves as a sealing surface and a sliding surface at the same time.

Since the tapered tube 8 is formed by press molding, the bottom surface of the flange portion 8a serving as a sealing surface and a sliding surface is sufficiently smooth and does not need to be machined. There is no need to carefully machine the bottom surface as in the prior art, and the number of processing steps and the accompanying cost can be reduced.

In the above description, the bottom surface of the flange portion 8a of the tapered tube 8 serving as a sealing surface and a sliding surface can be easily made slippery, for example, by applying a coating of a synthetic resin material. Small diameter fitting part 5
The sliding resistance of No. 2 is further reduced.

Incidentally, as in the above embodiment, the ball stud 1
When the tapered tube 8 is interposed between the tapered shaft portion 1b and the tapered hole 6a of the link member 6, the diameter of the tapered shaft portion 1b of the ball stud 1 is reduced by the thickness of the tapered tube 8. The diameter of the spherical portion 1a, the ball seat 2, the socket 3 and the like can be reduced along with the reduction in the diameter of the tapered shaft portion 1b, and the additional effect that the ball joint can be reduced in size and weight can be achieved. Can play.

[0015]

As described above, according to the present invention, the tapered tube, which is a press-formed product, is fitted to the tapered shaft portion of the ball stud, and the small-diameter fitting portion of the dust cover fitted to the outer periphery of the tapered shaft portion. Upper surface elastically contacts the lower surface of the flange portion of the tapered pipe,
Conventionally required because the outer peripheral surface of the tapered shaft portion where the inner peripheral surface of the small-diameter fitting portion of the dust cover elastically contacts and the lower surface of the flange portion of the tapered tube where the upper surface of the small-diameter fitting portion elastically contacts. The precision man-hour for machining the surface where the small-diameter fitting portion of the dust cover is elastically contacted is reduced by at least half, and the man-hour and manufacturing cost of the ball joint and its related parts can be significantly reduced. It is possible to obtain a ball joint with excellent functions such as improvement of the sealing property and slidability of the sealing part by the part and prevention of twisting of the dust cover accompanying the sealing function, which can bring a great effect in practical use. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a main part showing an example of a conventional structure.

[Description of Signs] 1 ball stud 1a spherical portion 1b taper shaft portion 2 ball seat 3 socket 5 dust cover 6 link member 6a taper hole 8 taper tube 8a flange portion 51 large diameter fitting portion 52 small diameter fitting portion

Claims (1)

(57) [Scope of request for utility model registration] A ball joint comprising a ball stud, a ball seat for fitting and holding a spherical portion of the ball stud, and a socket for fitting the ball seat, wherein the dust is made of an elastic material such as rubber. A large diameter fitting portion of the cover is fitted to the socket, and a small diameter fitting portion of the dust cover is fitted to the ball stud and sealed so that dust does not enter from outside. A tapered tube having a flange at the lower end is fitted, and the upper surface of the small diameter fitting portion of the dust cover fitted around the tapered shaft portion of the ball stud elastically contacts the lower surface of the flange of the tapered tube. A seal surface is formed by an outer peripheral surface of a tapered shaft portion on which an inner peripheral surface of a small-diameter fitting portion of the dust cover elastically contacts and a lower surface of a flange portion of a taper tube on which an upper surface of the small-diameter fitting portion elastically contacts. Ball joint dust cover mounting structure.