JPS6330813Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a joint in which a stable stud operation torque can be obtained despite variations in dimensional accuracy during assembly by incorporating a highly elastic member such as rubber.

BACKGROUND OF THE INVENTION Conventionally, ball joints used in steering linkages and suspensions of automobiles and the like include those shown in FIG. 1, for example.

In FIG. 1, 1 is a ball joint socket, which has a screw hole 1a at its lower end for connecting with a link member.
Inside, a ball stud 3 is inserted through a bearing 2 made of a highly wear-resistant plastic material.
The ball part 4 of the ball joint socket 1 is slidably attached thereto, and the ball stud 3 is assembled to the ball joint socket 1 by fitting the plate 5 next to the bearing 2, and by tightening the opening edge 6 of the ball joint socket 1 with a roller, etc. As shown in the figure, a specified operating torque is obtained by the sliding resistance between the ball stud 3 and the bearing 2 due to the elastic force of the bearing 2 determined by the caulking load.

However, in such conventional ball joints, since the bearing 2 is made of a highly wear-resistant plastic material, the bearing 2 is a so-called low-elasticity member that does not easily deform under the assembly load. , ball joint socket 1
Due to the caulking process, when the ball stud 3 is assembled, the elastic force changes greatly due to slight variations in dimensions. Therefore, unless the dimensional accuracy of the bearing and press-fitted parts is improved, the elastic force generated by the deformation of the bearing after press-fitting will vary greatly, and the operating resistance of the ball stud may be too high or too low, making it difficult to find an appropriate operating resistance. The problem was that it was difficult to obtain.

The present invention was developed in view of these conventional problems, and the purpose of this invention is to make it possible to obtain an appropriate operating resistance of a ball stud even if there are variations in dimensional accuracy when press-fitting a bearing. In order to achieve this, the caulking or drawing side of the bearing made of a low elasticity member is made thick, and the non-caulking or non-drawing side is made thin, and a high elasticity member such as rubber is interposed on the thin side of the bearing, so that it can be used together with a ball stud. It is designed to be press-fitted into a ball joint socket.

Hereinafter, the present invention will be explained based on the drawings.

FIG. 2 is a sectional view showing an embodiment of the present invention.

First, the structure will be described. Reference numeral 1 denotes a ball joint socket, which has a screw hole 1a at its lower end for connecting a link member. 3 is a ball stud that integrally has a ball portion 4 that is slidably incorporated into a ball joint socket;
The ball part 4 of the ball stud 3 is a bearing 10
Ball joint socket 1 when press-fitted into
The bearing 10 is made of a highly abrasion resistant and low elastic material such as polyamide resin, polyacetal resin, reinforced plastic, or reinforced plastic containing glass wool.

In the present invention, the bearing 10 is a thick walled portion 10 which is thickened on the opening edge 6 side of the ball joint socket 1 which is caulked through the plate 5.
a, and has a structure in which a thin wall portion 10b is formed which is thinner on the non-caulked side which is the lower side of the ball portion 4. Thin wall portion 10b of bearing 10
A high elasticity member 12 is interposed between the ball joint socket 1 and the ball joint socket 1, and the high elasticity member 12 is made of a material such as urethane, which has a large elastic deformation under the caulking load when the ball portion 4 of the ball stud 3 is assembled together with the bearing 10. The high elasticity member 12 is made as an integral part of the bearing 10 by composite molding on the bearing 10.

Next, the operation of the embodiment shown in FIG. 2 will be explained with reference to the graph shown in FIG.

Figure 3 shows the operating torque based on the sliding resistance between the ball stud and the bearing with respect to the bearing press-fit allowance when the bearing is press-fitted into the ball joint socket by caulking. Curve A shows the characteristics due to the structure.
The characteristic of the embodiment shown in FIG. 2 is shown by curve B.

In other words, in a conventional ball joint that uses a bearing made of a low-elasticity member as is, the change in operating torque with respect to the bearing press-fitting amount, that is, the amount of deformation of the bearing made of a low-elasticity member, is as shown in curve A. As the press-fitting allowance increases, it rises almost quadraticly.For example, if there is a variation in the dimensional accuracy of the bearing press-fitting allowance within the range shown by the arrow, this corresponds to the length of the vertical axis between points a1 and a2. This causes variations in operating torque.

On the other hand, in the embodiment shown in FIG. 2, the operating torque changes gradually as shown by curve B with respect to the increase in bearing press-fitting allowance. This change in curve B is due to the fact that the high elasticity member 12 is provided below the bearing 10 as a buffer material, so when the bearing 10 is press-fitted by caulking, the high-elasticity member 12 is first elastically deformed, and the press-fitting allowance of the high elasticity member is The increase in elastic force is smaller than that of the bearing 10 made of a low-elastic member, and only when the press-fitting allowance increases and the elastic force of the high-elastic member 12 increases, the bearings 10a and 10b made of a low-elastic member begin to undergo elastic deformation. This results in a large change in operating torque relative to the bearing press-fit allowance.

As is clear from the characteristics of curve B according to the present invention shown in FIG.
Only a change in the operating torque corresponding to the length of the vertical axis at point b2 occurs, and even if there is a variation in the same dimensional accuracy, the change in the operating torque can be suppressed significantly compared to the conventional case, and as a result, the bearing 10 and Stable operating torque can be achieved without increasing the dimensional accuracy of the ball joint socket 1, etc.

FIG. 4 is a sectional view showing another embodiment of the present invention, and this embodiment is characterized in that the bearing is press-fitted into the ball joint socket by narrowing the open end of the ball joint socket. shall be.

That is, the bearing 10 that slidably encloses the ball portion 4 of the ball stud 3 has a thick wall portion 10a on the constriction side of the ball joint socket 1, that is, on the opening edge 6 side, as in the embodiment shown in FIG. The thin wall portion 10b of the bearing 10 has a structure in which a thin wall portion 10b is formed on the non-drawn side which is the lower side of the ball portion 4.
A highly elastic member 12 is interposed between the ball joint socket 1 and the ball joint socket 1. In this example, the third
Appropriate operating torque can be obtained by suppressing fluctuations in operating torque due to variations in bearing press-fitting allowance shown by curve B in the figure.

In the embodiment shown in FIG. 4, the bearing 10
One or more slits 14 are formed in the thick wall portion 10a of the bearing 10a so that the ball stud 3 can be easily press-fitted into the bearing 10a. In addition, in both the embodiments shown in FIGS. 2 and 4, in order to reduce the wear of the bearing 10, the ball stud 3 is
It is desirable to form a plurality of oil grooves on the sliding surface.

FIG. 5 is a sectional view showing another embodiment of the present invention, which is characterized by the use of a stud having an axial end.

That is, in FIG. 5, the stud 3 has a shaft-shaped end 16 rotatably incorporated into the joint socket 1, and a flange 18 is integrally formed at the lower end. A bearing 10 made of a low-elastic material is attached to the shaft-like end 16 of the stud 3, and the bearing 10 is assembled into the joint socket 1 by caulking an end cover 20 press-fitted into the lower end of the joint socket 1. . This bearing 10 has a thick wall portion 10a that encloses the flange portion 18 of the stud 3 on the caulking side where the end cover 20 is provided, and a thin wall portion 10b integrally formed on the non-caulk side following the thick wall portion 10a. There is. A similarly cylindrical highly elastic member 12 is interposed on the outside of the thin wall portion 10b of the bearing 10.

Also, in order to facilitate press fitting of the axial end 16 of the stud 3 into the bearing 10, the bearing 10 is
One or more slits 14 are formed in the thick wall portion 10a in the axial direction.

The function of the embodiment shown in FIG. 5 is that the high elasticity member 12
When the stud 3 is inserted into the bearing 10, which has an integral structure with the bearing 10, it is assembled into the joint socket 1 from below, the end cover 20 is press-fitted, and the lower edge of the joint socket 1 is swaged with a roller swage or the like. The bearing 10 is pressed through the end cover 20 by the caulking process, and the rotational operating torque of the stud 3 relative to the bearing press-fit allowance is the curve B in FIG. The rotation operating torque of the stud 3 changes with respect to the same bearing press-fitting allowance as shown in FIG. 2, and a stable operating torque can be obtained by suppressing a large change in the operating torque due to variations in the bearing press-fitting allowance.

In any of the embodiments shown in FIGS. 2, 4, and 5, even if an excessive load is instantaneously applied to the bearing 10 through the stud 3 when the joint is in use, the highly elastic member 12 absorbs the impact. The highly elastic member 12 also has the function of a vibration absorbing material for vibrations applied through the studs, and when the joint of the present invention is used in an automobile suspension, it can achieve extremely high maneuverability. You can get ideas.

As explained above, according to the present invention, in a joint of an automobile, etc., a bearing made of a low elasticity member with a thick wall on the caulked or drawn side of the joint socket and a thin wall on the non-caulked or non-drawn side is used. The stud is slidably wrapped around the bearing, and a highly elastic member is interposed on the thin side of the bearing, and the stud is press-fitted into the joint socket, so that the stud does not operate in response to the bearing press-fit allowance caused by caulking or squeezing the joint socket. Since the change in torque is determined mainly by the elastic force of the high elasticity member, even if there is variation in the dimensional accuracy of the press-fit allowance, the change in operating torque due to this variation is significantly reduced compared to conventional joints. It is possible to obtain an appropriate operating torque within a predetermined range after assembly without increasing the dimensional accuracy of the bearing and press-fitted parts, and the quality of the joint can be significantly improved.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a conventional example, Fig. 2 is a sectional view showing an embodiment of the present invention, and Fig. 3 shows the relationship between operating torque and bearing press-fit allowance according to the present invention, together with the conventional example. A graph diagram, FIG. 4 is a sectional view showing another embodiment of the present invention that performs drawing processing,
FIG. 5 is a cross-sectional view of another embodiment of the present invention using a stud with an axial end. 1...Joint socket, 3...Stud,
4... Ball, 5... Plate, 6... Opening edge, 10... Bearing, 10a... Thick wall part, 1
0b... Thin wall portion, 12... High elasticity member, 14...
Slit, 16... Shaft end, 18... Flange, 20... End cover, 22... Oil reservoir.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In the joint of an automobile, etc., a stud is slidably wrapped, and the caulked or drawn side of the stud is thick, and the non-crimped or non-drawn side is thin. It has a bearing made of an elastic member and a highly elastic member interposed on the thin side of the bearing, and the bearing and the high elastic member are press-fitted into a joint socket to generate a desired operating resistance in the stud. A joint characterized by: (2) The end of the stud has a shaft shape, a bearing made of a cylindrical low elasticity member is attached to the shaft end, and the bearing is inserted into the joint socket via the same cylindrical high elasticity member. Claim 1 of utility model registration characterized by press-fitting
Joint as described in section.