JPH078900Y2 - Ball joint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a ball joint used for various linkage parts of an automobile.

[Conventional technology]

Conventionally, as a ball joint used for various linkage parts of an automobile, as shown in FIG.
The ball head 2a of the ball stud 2 is directly fitted and seated on the concave spherical surface portion 1b of the synthetic resin housing 1 having the concave spherical surface portion 1b which has the concave spherical surface portion 1b continuous with the opening 1a on the inner surface, and the housing 1 has a ball seat. The one with the structure that doubles as is used.

In FIG. 4, reference numeral 3 is a dust seal.

[Problems to be Solved by the Invention] In the ball joint using the conventional synthetic resin housing described above, the inner concave spherical surface portion 1b of the housing 1 excluding the opening portion 1a fits and seats the ball head 2a of the ball stud 2. The ball stud 2 is a bearing surface, and the ball head 2a is assembled by pushing the ball head 2a from the opening 1a of the housing 1 into the inner concave spherical surface portion 1b.

Therefore, the diameter of the opening 1a of the housing 1 cannot be made excessively smaller than the diameter of the ball head 2a, and as a result, the holding force of the ball stud 2 against the load in the pulling direction becomes small.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a ball joint using a synthetic resin housing, in which the holding force for the load of the ball stud in the pull-out direction is enhanced.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention adopts the following configurations (technical means).

That is, in a synthetic resin housing having an opening at the top and a concave spherical surface continuous with the opening on the inner surface, an annular notch groove is formed on the outer peripheral surface of the opening and the notch groove is formed. A male screw portion is formed on the cylindrical standing wall portion of the above, and a ball stud consisting of a ball head and a shaft portion integrally formed with the ball head fits and seats the ball head on the concave spherical surface portion of the housing. , The shaft portion is arranged so as to protrude from the opening portion, the male threaded portion of the cylindrical standing wall portion of the cutout groove has an annular collar portion at one end, and a metal tubular body having a female threaded portion on the inner surface is formed. The female screw portion is screwed and fixed, and an annular groove is formed on the outer peripheral surface of the opening of the housing by the annular flange portion of the metal cylindrical body, the outer peripheral cylindrical surface portion, and the bottom portion of the notch groove. One end of the annular groove is attached to the shaft of the ball stud. A ball joint and the other end is formed by fitted and fixed dust seal that is.

[Action]

The top opening of the synthetic resin housing has its radial strength greatly improved by the metal tubular body screwed into the annular cutout groove on the outer peripheral surface of the opening. It resists the load and prevents the opening from expanding and deforming.

Further, even if stress is relieved in the synthetic resin housing due to the influence of heat history, and a gap is formed between the female screw portion of the metal tubular body and the male screw portion of the outer peripheral surface of the housing opening, the screw portion Is engaged in the axial direction of the ball stud, the metal tubular body is prevented from slipping out, and the above action is maintained.

Furthermore, when a gap is formed in the threaded portion of the female threaded portion of the metal tubular body and the male threaded portion of the outer peripheral surface of the housing opening, a labyrinth is formed in the threaded portion, so that rainwater, etc. Intrusion is prevented.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to FIGS. 1 and 2 of the accompanying drawings showing an embodiment thereof.

In the figure, 10 is a synthetic resin housing, and the housing 10 has an opening 11 at the top and a concave spherical surface portion 12 continuous with the opening 11 on the inner surface.

The synthetic resin forming the housing 10 is a synthetic resin having appropriate elasticity and rigidity and excellent in self-lubricating property, and examples thereof include polyacetal resin, polyamide resin, and thermoplastic polyester resin. .

Reference numeral 13 denotes an annular cutout groove composed of a cylindrical standing wall portion 13a and an annular bottom portion 13b formed on an outer peripheral surface including the top opening portion 11 of the housing 10, and the cylindrical standing wall portion 13a of the cutout groove 13 has a male screw. The part 14 is formed.

Reference numeral 20 denotes a ball stud, and the ball stud 20 is a ball head 21 and a shaft portion integrally formed with the ball head 21.
Equipped with 22.

The outer diameter of the ball head 21 is the opening 11 of the housing 10.
Is formed larger than the diameter of the ball stud 20
Fits and inserts the ball head 21 from the top opening 11 of the housing 10 to seat it on the inner concave spherical surface portion 12 of the housing 10, and allows the shaft portion 22 to project from the opening 11 to the housing 10. It is assembled.

30 is a metal tubular body having an annular collar portion 30a at one end, an internal thread 30b on the inner surface, and a cylindrical surface portion 30c on the outer surface, and the metallic tubular body 30 has an internal female thread portion 30b in the cylinder of the housing 10. It is fixed by being screwed onto the male screw portion 14 of the standing wall portion 13a.

Due to the metal tubular body 30, the annular flange 30a of the metal tubular body 30, the outer cylindrical surface portion 30c, and the annular bottom portion 13b of the cutout groove 13 are provided on the outer peripheral surface of the opening 11 of the housing 10 to form an annular groove 40. Is formed.

50 is a dust seal made of a rubber elastic body, one end of which is fitted and fixed to the outer peripheral surface of the shaft portion 22 of the ball stud 20 and the other end is formed on the outer peripheral surface of the opening 11 of the housing 10. It is fitted and fixed in the annular groove 40.

Reference numeral 60 is a fastening clip that fastens and fixes the dust seal 50 in the annular groove 40.

The ball joint having the above-mentioned configuration has a radial strength due to the metal tubular body 30 in which the top opening 11 of the synthetic resin housing 10 is screwed and fixed to the annular cutout groove 13 on the outer peripheral surface of the opening 11. Since it is greatly improved, even if a load in the pulling-out direction is applied to the ball joint, the load is resisted and the ball head is prevented from coming out from the concave spherical surface portion of the housing.

In addition, even if stress relaxation occurs in the synthetic resin housing 10 due to the influence of heat history, and a gap is formed in the threaded portion between the female threaded portion 30b of the metal tubular body 30 and the male threaded portion 13a on the outer peripheral surface of the housing opening 11. Since the threaded portion is engaged in the axial direction of the ball stud, the metal tubular body 30 is prevented from coming off, and the above action is maintained for a long period of time.

Further, even if a gap is formed in the threaded portion between the female threaded portion 30b of the metal tubular body 30 and the male threaded portion 13a of the outer peripheral surface of the housing opening 11, a labyrinth is formed in the threaded portion, Rainwater is prevented from entering through the gap.

FIG. 3 shows another embodiment of the present invention.

In this embodiment, the ball joints having the above-described structure are integrally formed at both ends of the synthetic resin connecting rod 10a in the synthetic resin housing 10 of the joints. It is suitable for use in stabilizer links.

〔effect〕

The ball joint of the present invention having the above-mentioned configuration has the following unique effects.

The top opening portion of the synthetic resin housing is greatly improved in radial strength by a metal tubular body screwed into an annular cutout groove on the outer peripheral surface of the opening, and the metal tubular body has a ball stud. Since it acts as a large resistance force against the load in the pulling direction that acts on, the expansion deformation of the opening can be prevented, and the ball stud can be prevented from coming out of the housing.

Even if a stress is generated in the synthetic resin housing due to the influence of heat history, and a gap is formed between the female threaded portion of the metal tubular body and the male threaded portion of the outer peripheral surface of the housing opening, the threaded portion will be ball-shaped. Since the stud is engaged in the axial direction, the metal tubular body is prevented from coming off, and the above-mentioned effect of preventing the ball stud from coming out of the housing is maintained for a long period of time.

Even if a gap is formed in the threaded portion, a labyrinth is formed in the threaded portion, so that rainwater or the like can be prevented from entering through the threaded portion.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a ball joint of the present invention, FIG. 2 is an enlarged sectional view of an essential part of FIG. 1, FIG. 3 is a sectional view showing another embodiment of the present invention, and FIG. It is sectional drawing which shows a technique. 10: Synthetic resin housing, 11: Opening 12: Concave spherical surface, 13: Annular notch groove 14: Male thread, 20: Ball stud 21: Ball head, 22: Shaft 30: Metal cylinder, 30a: Annular Collar part 30b: Female thread part, 40: Annular groove 50: Dust seal

Claims (1)

[Scope of utility model registration request] 1. A synthetic resin housing having an opening at the top and a concave spherical surface continuous with the opening on an inner surface thereof, and an annular notch groove formed on the outer peripheral surface of the opening. A male screw portion is formed on a cylindrical vertical wall portion of the cutout groove, and a ball stud including a ball head and a shaft portion formed integrally with the ball head is fitted on the concave spherical surface portion of the housing. A metal cylinder that is seated in a seat and is arranged so that the shaft portion projects from the opening, the male thread portion of the cylindrical standing wall portion of the cutout groove has an annular collar portion at one end, and the female thread portion on the inner surface. An annular groove is formed on the outer peripheral surface of the opening of the housing by an annular flange portion, an outer peripheral cylindrical surface portion, and a bottom portion of the cutout groove. Is formed, and one end of the annular groove is attached to the shaft of the ball stud. Ball joint and the other end of the call has been dust seal is fitted and fixed.