JPS6342182Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a constant velocity universal joint that is applied to automobiles and the like.

Conventionally, as this type of joint, for example, as shown in FIGS. 1 and 2, an outer joint member a and an inner joint member b are used.
A ball cage d holding a plurality of balls c is interposed between the two members and each ball c is engaged in each of the ball grooves e and f in the axial direction of the opposing surfaces of both members a and b. As is known, in this case, the ball cage d has an outer spherical surface and an inner spherical surface that are concentric with each other, and in each spherical surface, the outer joint member a and the inner joint member b that are also concentric with each other are connected to each other. The inner spherical surface and the outer spherical surface are in surface contact with each other, and as a means for imparting uniform velocity to these surfaces, the inner spherical surface and the outer spherical surface are connected to each other on center points A and B that eccentrically center the groove bottom surfaces of each ball groove e and f. In other words, the ball grooves e and f of the outer joint member a are offset from each other. The groove depth becomes gradually shallower toward the root side, and both members a and b
When the bending angle is large, problems arise in terms of torque transmission between the ball e and the ball grooves e and f, as shown in FIG. In this regard, the device described in U.S. Pat. No. 3,879,960 has a ball groove with no undercut made of uniform continuous arcs, which improves torque transmission ability and facilitates cold working. intended.

However, the following problems still remain. That is, when a particularly large operating angle is taken, the ball c rides on the pocket edge of the cage d, resulting in the problem that smooth function cannot be achieved. Moreover, at the same time, there is a problem that the pocket edge of the cage d is damaged. Furthermore, it is difficult to increase the wall thickness of the cage for the same ball diameter, so when a large operating angle is used, the strength of the pocket part of the cage is insufficient.
This causes the inconvenience that cracks are likely to occur at the corners of the pocket.

Due to these defects, the above-mentioned conventional joints have left room for improvement in order to achieve higher operating angles. Based on this knowledge, the object of this invention is to provide a constant velocity universal joint that does not have the above-mentioned disadvantages.

In other words, the purpose of this invention was to provide a sufficient torque transmission capacity even when the joint assumes a large operating angle, and also to eliminate problems such as balls riding on the joint and damage to the cage. The purpose of this invention is to ensure smooth operation of the valve, thereby making it possible to obtain a larger operating angle.

The basic concept of this idea is to create a ball groove with no undercut, which is made up of continuous eccentric arcs, and to increase the thickness of the cage in the radial direction at the open end of the outer joint member. .

Therefore, in the constant velocity universal joint of this invention, a cage holding a plurality of balls is interposed between the inner joint member and the outer joint member, and each ball is placed between the inner joint member and the outer joint member. In a constant velocity universal joint that is engaged with a ball groove extending in an arc shape in the axial direction provided on a surface, the center point of the arc of the ball groove provided in both joint members is parallel to the axis of the joint and in the radial direction. on a line separated from the center surface of the joint by an equal distance in the axial direction, and the eccentric distance is at least equal to the distance from the center surface of the joint to the opening end surface of the outer joint member, and The cage has an inner spherical surface and an outer spherical surface each having a center point that is eccentric to the opposite side by an equal distance in the axial direction within a range smaller than the eccentric distance with respect to the center plane of the joint on the axis of the joint, and The spherical surface and the outer spherical surface are each in spherical contact with the outer spherical surface of the inner joint member and the inner spherical surface of the outer joint member, which are also eccentrically provided.

The embodiments shown in the drawings will be described below.

In FIG. 3, 1 is an outer joint member, 2 is an inner joint member, 3 is a ball, and 4 is a ball cage.

The outer joint member 1 and the inner joint member 2 are provided with ball grooves 5, 6 at circumferentially equally spaced positions, e.g., 6
These ball grooves 5,
6 extends in an arc shape in the axial direction.

That is, the ball groove 5 of the outer joint member 1 forms a series of circular arcs centered on point _O1 , and the ball groove 6 of the inner joint member 2 forms a series of circular arcs centered on point _O2 . .

The center points O ₁ and O ₂ of the arcs of the ball grooves 5 and 6 are as follows:
On a line parallel to the axis of the joint, eccentrically equidistant e ₁ from the center plane of the joint to the opposite side in the axial direction, and the eccentric distance e ₁ is from the center plane of the joint to the end face 1a of the outer joint member 1. It is set equal to the distance l.

The points q ₁ and q ₂ where the straight line connecting the center point P of the ball 3 and O ₁ and O ₂ intersect the axis of the joint are points corresponding to points A and B shown in Fig. 1. In the embodiment of FIG. 3 in which the single width l' of the inner joint member 2 and the width l of the outer joint member 1 are equal, the extension of the straight line connecting the ball center point p and points A and B is , the above-mentioned points O ₁ and O ₂ are located at the points where the end surface 1a of the outer joint member 1 and the end surface 2a of the inner joint member 2 intersect.

Incidentally, when the end of the ball groove 5 of the outer joint member 1 is chamfered as shown by the imaginary line 5a in FIG. 3, the above-mentioned point _O1 can be shifted inward by the amount of the chamfer.

On the other hand, the cage 4 has an inner spherical surface 7 and an outer spherical surface 8 having center points O ₃ and O ₄ eccentrically opposite to each other by an equal distance e ₂ from the center plane of the joint on the axis of the joint. Correspondingly, an outer spherical surface 9 and an inner spherical surface 10 are provided eccentrically on the inner joint member 2 and the outer joint member 1, and these are combined in spherical contact.

The eccentric distance e ₂ between the O ₃ points and O ₄ points above is e ₂ ≒ 1/2 ₁ (= 1/2 2 ), where O is the intersection of the axis of the joint and the center plane of the joint in Fig. ₃ . It is preferable to do so.

With the above configuration, ball 3 is
No matter what bending angle the two members 1 and 2 take, the ball grooves 5 and 6 align them on a plane that bisects the angle formed by the two members, and uniform velocity is maintained.

Even when both members 1 and 2 have a large bending angle as shown in FIG. 4, the depth of the groove on the back side of the ball groove 5 of the outer joint member 1 can be increased, so that sufficient torque transmission capacity can be maintained. can get.

Further, since the ball 3 does not ride on the pocket of the cage 4, the guidance of the ball 3 is stable and smooth operation can be ensured.

As explained above, this invention, in addition to making the ball groove of the eccentric arc into a ball groove with no undercut made of a uniform continuous arc, Since the wall thickness is increased, the wall thickness for cold forging of the ball groove is increased, so while maintaining the advantage of facilitating cold forging of the ball groove, the following effects are also achieved. That is, the depth of the ball groove on the back side of the outer joint member, that is, on the side opposite to the open end, can be made deeper, and sufficient torque transmission ability can be exhibited even for a large operating angle. In addition, the increased radial wall thickness of the cage on the open end side of the outer joint member prevents the ball from riding up on the pocket edge of the cage, even at particularly large operating angles, and ensures stable ball guidance. Smooth operation can be obtained and damage to the pocket edge of the cage can be prevented. In addition, the pushing force acting on the ball due to the wedge angle of the ball groove is generated toward the opening of the outer joint member and is supported by the cage, but the above-mentioned member receives this force. Since the cage is thick, the cage has sufficient strength and can be expected to prevent damage and improve durability. Thus, according to this idea,
Since the problems that can occur in the cage under large operating angles are eliminated, a structure of a constant velocity universal joint that can provide an even larger operating angle than before can be realized.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a conventional constant velocity universal joint, Figure 2
3 is a longitudinal sectional view showing the main parts of the constant velocity universal joint according to the present invention, and FIG. 4 is a longitudinal sectional view showing the constant velocity universal joint in its operating state. 1... Outer joint member, 2... Inner joint member, 3
... Ball, 4 ... Cage, 5, 6 ... Ball groove, 7, 8 ... Inner and outer spherical surfaces of cage, 9, 10 ... Inner and outer spherical surfaces of joint member, O ₁ , O ₂ ... Center of ball groove, O ₃ ,
O ₄ ...Center of the cage's inner and outer spheres.

Claims (1)

[Scope of utility model registration request] A cage holding a plurality of balls is interposed between the inner joint member and the outer joint member, and each ball is provided on opposing surfaces of the inner joint member and the outer joint member and extends in an arc shape in the axial direction. In a constant velocity universal joint that engages with a ball groove, the center point of the arc of the ball groove provided in both joint members is parallel to the axis of the joint and radially separated from the center plane of the joint. the cage is axially eccentric to the opposite side by an equal distance, and the eccentricity distance is at least equal to the distance from the center plane of the joint to the open end surface of the outer joint member, and the cage is axially eccentric to the opposite side by an equal distance; has an inner spherical surface and an outer spherical surface having center points eccentric to opposite sides by an equal distance in the axial direction within a range smaller than the eccentric distance, and the inner spherical surface and the outer spherical surface are provided eccentrically as well. A constant velocity universal joint characterized in that the outer spherical surface of the inner joint member and the inner spherical surface of the outer joint member are in spherical contact with each other.