JPS602531B2 - ball joint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ball joint in which a ball portion is held by an elastic bearing.

Examples of conventional ball joints are shown in Figures 1, 2, and 7.
As shown in the figure. The conventional example shown in Fig. 1 is, for example,
As in No. 19363, the spherical seat of the bearing 3 is arranged with a radius R, , R, which is considerably larger than the radius of the spherical part of the ball stud 1.
By combining the two spherical surfaces of the ball stud 1, a space is formed between the ball stud 1 and the ball stud 1.

With this configuration, the wall thickness distribution is difficult to achieve as designed due to shrinkage strain during manufacturing of the bearing 3, and therefore, torque variation is large.

In addition, since the bearing 3 does not have a rotation prevention function, it needs to be slightly press-fitted into the case 5, making it difficult to assemble, and is greatly affected by the accuracy of the inner diameter of the case 5, resulting in variations in starting torque. The disadvantage is that it becomes large.

Furthermore, in another conventional example shown in FIG. 2, for example, as in Utility Model Publication No. 55-3914, the bearing 3 before assembly has the same hemisphere as the hemispherical surface formed with radius R as shown in FIG. The ball stud 1 is fixed by bending and deforming the cylindrical portion of the bearing 3, with one end of the inner diameter of the case 5 having a hemispherical shape.

In this configuration, since the case 5 is partially machined into a hemispherical shape, it is difficult to ensure machining accuracy.

In addition, the starting torque is 100% influenced by the machining accuracy of the hemispherical part of the case 5 and the thickness accuracy of the bearing 3, so it tends to vary. Furthermore, depending on the degree of bending deformation of the bearing 3, the swing angle of the ball stud 1 tends to vary.

The present invention has been made in view of these drawbacks of the conventional examples, and it is an object of the present invention to eliminate the above-mentioned drawbacks.

The characteristics required for a ball joint are: a. There is little variation in starting torque due to manufacturing errors b. C. There is little reduction in starting torque due to long-term use. No relative displacement between the case and the bearing d. For example, joints with various starting torques can be easily manufactured.

The present invention satisfies the above-mentioned required characteristics by having the configuration described below with reference to the accompanying drawings.

Fig. 3 is a sectional view showing the configuration (assembly) of the ball joint of the present invention, Fig. 4 is a sectional view of the case before assembly, Fig. 5 is a sectional view of the bearing with the ball joint inserted, and Fig. 6 is a sectional view showing the configuration (assembly) of the ball joint of the present invention.
The figure is a side view of the ball joint.

In Figure 3, 1 is the ball stud, 5 is the case,
An elastic bearing 3 into which the pole stud 1 is inserted is inserted into a cylindrical part 8 having a flat part 7, and a cap 4 that holds one end of the ball stud 1 is attached to the entrance part of the case 5 (lower part of the figure). Fixed.

A space 9 is partially formed between the spherical portion 11 of the ball stud 1 and the inner circumference of the bearing 3. Further, a force bar attachment member 6 is fixed to one end of the case 5, and the dust cover 2 is attached thereto.
As shown in FIG. 4, the case 5 has a cylindrical portion 8 and a flat portion 7 on its inner surface. The outer diameter and length of the bearing 3 are set as D-△D (Fig. 5) and L+△L (Fig. 5) with respect to the inner diameter D and length L of the case 5 in Fig. 4. Let the inner diameter of the sphere be d+Ad with respect to the outer diameter d of the ball stud 1 (Fig. 6). The ball stud 1 is inserted into the bearing 3 formed as described above, rounded with a cap 4, and fixed by pressing and caulking.

By doing this, the space 9 is formed on the inner surface of the bearing 3, so by applying a lubricant such as grease to the inner surface of the bearing 3, the space 9 can be used as a lubricant pot. An oil-free lubrication structure is achieved.

This is because when compressed between the flat part 7 of the case 5 and the cap 4, the equatorial part 10 (Fig. 5) of the bearing 3 is the thinnest, so this part deforms outward. . Due to the increase in the outer diameter of the bearing 3 at this time,
Since the bearing 3 completely adheres to the inner wall of the case 5, relative displacement between the case 5 and the bearing 3 can be stopped.

Due to the deformation of the bearing 3, the inner sphere has an equatorial portion 10.
Since the support surface 12 is formed with the spherical portion 11 (FIG. 3) of the ball stud 1 which faces the ball stud 1 via the bulge, stable torque can be obtained with little variation in the starting torque due to manufacturing errors.

. Since compressive stress can be applied over the entire area of the bearing 3, by using an elastic material for the bearing 3, a wear compensation function can be obtained by utilizing this elasticity.

Also,. By choosing △L of the total length L + △L of the bearing 3, the ball joint 1 has a separate starting torque.
can be easily obtained, or the above effect can be similarly obtained by changing the depth L of the case 5 for the completed bearing 3. Since the outer diameter of the bearing 3 is smaller than the inner diameter of the case 5, assembly is easy, and since the bearing 3 is compressively deformed over the entire area, the D
, L and the bearing 3 are completely absorbed, and stable torque with little variation can be obtained. Furthermore, the use of an elastic body for the bearing 3 has the effect of damping high frequency vibrations such as steering shimmy.

[Brief explanation of the drawing]

Figures 1 and 2 are sectional views showing examples of slave ball joints, Figure 3 is a sectional view showing the configuration (assembly) of the ball joint of the present invention, and Figure 4 is before assembly of the nurse. Figure 5 is a cross-sectional view of the bearing with the pole joint inserted, Figure 6 is a side view of the ball joint, and Figure 7 is a cross-sectional view of the conventional bearing shown in Figure 2 before assembly. be. DESCRIPTION OF SYMBOLS 1... Ball stud, 2... Dust cover, 3... Bearing, 4... Cap, 5... Case, 6... Cover mounting member, 7... Flat part, 8... ...Cylindrical part, 9...Space part, 10...Equatorial part, 1
1...Ball club, 12...Our support side. Figure 1: Kiyoshi Z Figure: 3: Purple: 4 Figure: Me: 5: Violet: 6: Figure

Claims (1)

[Claims] 1 A case with a cylindrical part inside and a flat part at one end, a cylindrical outer shape with a slightly smaller diameter and slightly larger length than the inner diameter and length of the cylindrical part of the case, and a ball stud to hold it. It consists of a bearing in which a spherical inner cavity with a diameter slightly larger than the diameter of the spherical part and an opening is formed in a part, and a cap member that holds the bearing in the case. By pressing horizontally and holding it inside the case,
A ball joint characterized in that the bearing is deformed so that its outer peripheral surface is attached to the inner surface of the case, and a space is formed in a part between the bearing and the ball of the ball stud.