JPH05231435A - Constant velocity universal joint - Google Patents

Abstract

PURPOSE:To increase an operating angle in a constant velocity universal joint of cross groove type. CONSTITUTION:The guide groove 1a of an outer ring 1 has a form twisted in both peripheral and radial direction. In addition, the groove 1a comprises a guide groove 1a1 having a form twisted in one peripheral direction with an axial line X and twisted in a bore direction at a radial crossing angle of betatoward the right side of the illustration, and another guide groove 1a2 having a form twisted in an opposite peripheral direction and externally twisted at the radial crossing angle '. Also, the guide groove 2a of an inner ring has a form twisted in peripheral and radial directions, similar to the case of the guide groove 1a of the outer ring 1, and comprises a guide groove 2a1 forming a pair with the guide groove 1a1, and a guide groove 2a2 forming a pair with the guide groove 1a2. The guide grooves 2a1 and 2a2 are respectively twisted in peripheral and radial directions opposite to the guide grooves 1a1 and 1a2 forming the pairs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a cross groove type constant velocity universal joint used for propeller shafts and drive shafts of automobiles.

[0002]

2. Description of the Related Art A cross-groove type constant velocity universal joint is a track portion where guide grooves of an inner ring and a guide groove of an outer ring which form a pair are twisted in opposite circumferential directions, and where the guide grooves intersect. It is a type that holds and controls the torque transmission ball with, but because of its structure, rattling between the torque transmission ball and the guide groove can be reduced, so it is especially suitable for propeller shafts and drive shafts of automobiles where rattling is disliked. It is used a lot. Guide grooves twisted in one direction in the circumferential direction and guide grooves twisted in the other direction are alternately formed on the inner peripheral surface of the outer ring, and the outer peripheral surface of the inner ring is opposed to the guide grooves of the paired outer ring. , Guide grooves twisted in opposite directions in the circumferential direction are alternately formed.

[0003]

In the cross groove type constant velocity universal joint, the torque transmission balls are held and controlled because the wedge angles are formed at the intersections of the ball tracks, and the torque transmission balls are held by the wedge angles. This is because it is pushed to the pocket surface of the vessel. As a result, the torque transmitting ball is always held at the intersection of the ball tracks, and is always maintained within the angle bisector of the operating angle even when an angular displacement occurs between the inner and outer wheels. In this way, the cross-groove type constant velocity universal joint has constant velocity,
Moreover, it is an excellent one with less rattling, but it has the disadvantage that the working angle can not be made much larger than the constant velocity universal joint of the type that controls the torque transmission balls by offsetting the guide grooves of the inner and outer rings. is there. This is because if the operating angle is large, the wedge angle is reversed and the balance of the forces acting from the torque transmitting balls to the cage is lost. Therefore, the cage cannot maintain the balance of force and becomes unstable.

On the other hand, as a means for eliminating such inconvenience, it is conceivable to increase the twist angle of the guide grooves of the inner and outer rings to prevent the wedge angle from being reversed. However, since the guide grooves of the inner ring and the outer ring are formed alternately by changing their directions in the circumferential direction, the twist angle cannot be increased so much in consideration of interference with the adjacent guide grooves.

As described above, in the cross-groove type constant velocity universal joint, increasing the working angle is one of the pending issues, and an object of the present invention is to solve this.

[0006]

A constant velocity universal joint of the present invention includes a guide groove twisted in one circumferential direction and one radial direction with respect to an axis and a guide groove twisted in the other circumferential direction and the other radial direction. A ball track is formed by pairing the outer ring with the grooves alternately provided on the inner peripheral surface and each guide groove of the outer ring, and the direction opposite to the guide groove of the paired outer ring in the circumferential direction and the radial direction. An inner ring with twisted guide grooves alternately provided on the outer peripheral surface,
It has a torque transmission ball arranged on each ball track and a retainer for holding the torque transmission ball.

[0007]

The guide grooves of the inner and outer rings have a shape twisted in the circumferential direction and the radial direction, and the guide grooves forming a ball track in pairs twist in opposite directions in the circumferential direction and the radial direction. Therefore, the ball track has a shape intersecting not only in the circumferential direction but also in the radial direction. In this way, the critical operating angle can be increased by imparting the radial crossing angle to the ball track. this is,
For the following reasons. That is, when the contact angle between the torque transmitting ball and the guide groove is α, the radial crossing angle of the ball track centerline with respect to the axis is β, and the circumferential crossing angle is γ, θ of the limit working angle 2θ is expressed by the formula shown in FIG. However, if the value of β = −π / 2 to 0 is substituted in this equation, the absolute value of tan θ becomes larger than the case of β = 0, and the absolute value of θ increases. is there.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the constant velocity universal joint of this embodiment has an outer ring 1 having a guide groove 1a on its inner peripheral surface, an inner ring 2 having a guide groove 2a on its outer peripheral surface, a guide groove 1a and a guide groove 1a. It is composed of a torque transmission ball 3 arranged on a ball track formed between the groove 2a and a cage 4 for holding the torque transmission ball 3.

As shown in FIGS. 2 and 3, the guide groove 1a of the outer ring 1 has a circumferentially and radially twisted shape.
When the guide groove 1a is viewed from the axis line X in FIG. 2, the guide groove 1a1 is twisted counterclockwise with a circumferential crossing angle γ and twisted in the inner diameter direction with a radial crossing angle β toward the back side of the paper. , A guide groove 1a2 having a shape twisted clockwise with a circumferential crossing angle γ and twisted with a radial crossing angle β in the outer diameter direction toward the back side of the drawing. The guide groove 1a1 and the guide groove 1a2 are alternately formed on the inner peripheral surface of the outer ring 1, and the directions of the circumferential crossing angle γ and the radial crossing angle β are opposite to each other. Similarly to the guide groove 1a of the outer ring 1, the guide groove 2a of the inner ring also has a twisted shape in the circumferential direction and the radial direction.
As shown by the chain line, the guide groove 2 which forms a pair with the guide groove 1a1
a1 and a guide groove 2a2 paired with the guide groove 1a2. The guide grooves 2a1 and 2a2 respectively have a circumferential crossing angle γ in opposite directions and a radial crossing angle β in opposite directions with respect to the paired guide grooves 1a1 and 1a2 (both crossing angles correspond to the axis X). It is twisted with the standard.
The guide groove 2a1 and the guide groove 2a2 are alternately formed on the outer peripheral surface of the inner ring 2, and the directions of the circumferential crossing angle γ and the radial crossing angle β are opposite to each other.

The torque transmission ball 3 is provided with guide grooves 1a, 2a.
Located on the crossed track part between the inner and outer wheels 1, 2
Torque transmission between them. Even when the inner and outer wheels 1 and 2 have an operating angle, the torque transmitting balls 3 are always held by the intersecting track portions and are maintained within the angle bisector of the operating angle.

In this constant velocity universal joint, the guide grooves 1a, 2a of the inner and outer races 1, 2 have a twisted shape not only in the circumferential direction but also in the radial direction. Increase compared to the one. For example, the circumferential intersection angle γ
A comparison of constant velocity universal joints with a radial crossing angle of 10 ° is 12.82 ° in the case where the radial crossing angle β is not provided (β = 0). β
With (provided that β = −2 °), the limit operating angle is 2
θ increases to 15.90 °.

The present invention is applicable regardless of whether the contact groove between the inner and outer races and the torque transmitting ball is in the angular contact or the circular contact.
However, in the case of the angular contact, the radial crossing angle of the guide groove needs to be provided in the direction as shown in FIG. In the case of a circular contact, the radial crossing angle of the guide groove may be provided in the direction as shown in FIG. 2 or in the opposite direction. That is, the guide groove 1a1 may be twisted in the outer diameter direction toward the back side of the paper, and the guide groove 1a2 may be twisted in the inner diameter direction. Further, the radial crossing angle may be provided in the same direction (trumpet shape) for all the tracks. This is considered to be because, in the case of a circular contact, the contact angles are reversed between the guide grooves, so that a good balance can be obtained inside.

[0014]

According to the present invention, since the guide grooves for the inner and outer rings are formed to be twisted not only in the circumferential direction but also in the radial direction, the limit working angle of the cross groove type constant velocity universal joint can be reduced from the conventional one. It can be increased compared to the one.

[Brief description of drawings]

FIG. 1 is a sectional view showing a constant velocity universal joint according to an embodiment of the present invention.

FIG. 2 is a view of the outer ring in FIG.

3 is a cross-sectional view of the outer ring in FIG. 2 taken along line 1-1 (FIG. 3A) and FIG.

FIG. 4 is a diagram showing an expression for obtaining a limit operating angle 2θ.

[Explanation of symbols]

 1 Outer ring 1a Guide groove 2 Inner ring 2a Guide groove 3 Torque transmission ball 4 Cage β Circumferential crossing angle γ Radial crossing angle 2θ Limit operating angle

Claims (1)

[Claims] 1. An outer ring in which guide grooves twisted in one circumferential direction and one radial direction with respect to an axis and guide grooves twisted in the other circumferential direction and the other radial direction are alternately provided on an inner circumferential surface. , A ball track is formed in pairs with each guide groove of the outer ring, and guide grooves twisted in opposite circumferential and radial directions are alternately provided on the outer peripheral surface with respect to the guide grooves of the paired outer ring. A constant velocity universal joint characterized by having an inner ring, a torque transmission ball arranged on each ball track, and a cage for holding the torque transmission ball.