JPH09291945A - Fixed type constant velocity joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the strength and durability of the cage of a constant velocity joint wherein the center of each of the inner and outer surfaces of the spherical shapes of a track groove and a cage is offset from a joint center. SOLUTION: The center A1 of a curve-form pole groove 3 formed in the spherical inner surface 2 of an external joint member 1 and the center A2 of a curve-form pole groove 13 formed on the spherical outer surface 12 of an internal joint member 11 are laterally offset from a joint center O0 . A torque transmission pole 21 incorporated between the pole groove 3 of the external joint member 1 and the pole groove 13 of the inner joint member 11 is contained in a pocket 35 formed in a cage 31. The centers B1 and B2 of the spherical outer and inner surfaces 33 and 34 of the cage 31 are laterally offset from the joint center O0 . A side positioned facing in the peripheral direction of the cage of a pocket 35 formed in the cage 31 forms a slope inclining with spread in the direction of the outside diameter of a joint. The spherical area on the inside diameter side of a column part formed between the pockets 35 is increased and the strength and durability of the cage 31 are improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixed type constant velocity joint incorporated in an automobile or an industrial machine.

[0002]

2. Description of the Related Art A fixed type constant velocity joint shown in FIG. 5 is conventionally known. This constant velocity joint has a spherical inner surface 41 of the outer joint member 40.
A plurality of curved ball grooves 42 are formed in the inner joint member 4
The spherical outer surface 44 of 3 is provided with the same number of curved ball grooves 45 as the ball grooves 42, and the torque transmitting balls 46 are assembled between the ball grooves 42 of the outer joint member 40 and the ball grooves 45 of the inner joint member 43. There is.

Further, the outer joint member 40 and the inner joint member 4
3, a cage 47 having a spherical outer surface 48 and a spherical inner surface 49, which are guided by the spherical inner surface 41 and the spherical outer surface 44, is formed in the cage 47, and a plurality of pockets 50 for accommodating the torque transmitting balls 46 are formed in the cage 47. Is formed.

Further, the spherical inner surface 41 of the outer joint member 40.
And each center of the spherical outer surface 44 of the inner joint member 43 is located at the joint center O ₀ , and the center A ₁ of the ball groove 42 formed in the outer joint member 40 and the ball provided in the inner joint member 43. The center A _{2 of the} groove 45 is offset to the left and right at the same distance with respect to the joint center O ₀ .

In the above-mentioned constant velocity joint, after the cage 47 and the inner joint member 43 are assembled inside the outer joint member 40, the outer joint member 40 and the inner joint member 43 are relatively inclined. Pocket 50 formed in the cage 47
One of the above is exposed to the outside of the outer joint member 40, and the operation of incorporating the torque transmitting balls 46 into the pockets 50 is alternately repeated to incorporate the torque transmitting balls 46 into all the pockets 50. .

When the torque transmitting ball 46 is assembled as described above, the torque transmitting ball 46 that has been assembled first moves in the pocket 50, and the torque transmitting ball 46 that is assembled first is moved.
6 moves until the final torque transmission ball 46 is assembled, as shown in FIG. Therefore, in the pocket 50 formed in the cage 47, the side surfaces 51 facing each other in the circumferential direction of the cage 47 are parallel surfaces in order to avoid interference with the torque transmission balls 46.

The constant velocity joint normally transmits torque between the outer joint member 40 and the inner joint member 43 via six torque transmitting balls 46. In a constant velocity joint having six balls, the two pockets 5 located at the opposite positions of the six pockets 50 formed in the cage 47.
0 has a long window shape which is long in the cage circumferential direction with respect to the other pockets 50, and the long joint pocket 50 is used to assemble the inner joint member 43 into the cage 47 as shown in FIG. 7. I have to.

By the way, if the inner and outer diameters of the cage 47 are not changed from the current ones and the number of torque transmitting balls 46 is increased to more than 6, the load capacity of the constant velocity joint is improved. Since the space between the pockets 50 formed in the cage is small, it is not possible to form a long window pocket when trying to secure the strength of the pillar of the cage 47. Joint member 4
The assembling method of assembling No. 3 cannot be adopted.

In this case, as shown in FIG.
By providing the inlay 52 having an inner diameter D ₂ smaller than the outer diameter D ₁ of the inner joint member 43, the inner joint member 43 can be accommodated in the cage 47 by utilizing the inlay 52.
However, there is a disadvantage that the inner diameter sphere area (the sphere area of the portion indicated by the dimension L ₁ ) on the spigot 52 side of the cage 47 is reduced.

As shown in FIG. 9, such a disadvantage is caused by the center B ₁ of the spherical outer surface 48 of the cage 47 and the spherical inner surface 4 of the cage 47.
It can be eliminated by offsetting the center B _{2 of} 9 with respect to the pocket center line X left and right.

That is, by offsetting the center B ₂ of the spherical inner surface 49 to the left side in FIG. 9 with respect to the pocket center line X of the cage 47, the inner diameter sphere area on the inlay 52 side (the sphere area of the portion indicated by the dimension L ₂ ) ) Increases.

However, in a constant velocity joint in which the centers of the ball grooves 42, 45 are laterally offset with respect to the joint center, and the spherical outer surface 48 and the spherical inner surface 49 of the cage 47 are also laterally offset with respect to the joint center, Due to the positional relationship of the respective offsets, when the torque transmission ball 46 is assembled, the movement of the torque transmission ball 46 that is first assembled is large on the outer diameter side of the joint and small on the inner diameter side as shown in FIG. Will be drawn.

In such a case, if the side surfaces 51 of the pocket 50 formed in the cage 47, which face each other in the cage circumferential direction, are parallel surfaces, the spherical area on the inner diameter side of the pillar portion 53 formed between the pockets 50 becomes small. However, there arises a problem that the strength and durability of the cage 47 are reduced.

[0014]

DISCLOSURE OF THE INVENTION It is an object of the present invention to reduce the strength and durability of a cage in a fixed type constant velocity joint in which the centers of the spherical outer surface and the spherical inner surface of the cage are offset. A technical challenge is to improve durability.

[0015]

In order to solve the above-mentioned problems, in the present invention, the centers of the spherical outer surface and the spherical inner surface of the cage are offset to the left and right by an equal distance with respect to the joint center, and the outer joint member A fixed type in which the center of the ball groove is offset in the joint center direction with respect to the center of the spherical outer surface, and the center of the ball groove of the inner joint member is offset by an equal distance in the joint center direction with respect to the center of the spherical inner surface. In the constant velocity joint, a pair of side surfaces facing each other in the cage circumferential direction of the pocket formed in the cage is configured as an inclined surface that is widened and inclined toward the outer diameter side of the joint.

Here, the pair of side surfaces of the pocket which is inclined with an expansion in the outer diameter direction of the joint may be a flat surface or a concave curved surface.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, the constant velocity joint has an outer joint member 1, an inner joint member 11 and a torque transmission ball 21 as in the conventional constant velocity joint described in FIG.
And a cage 31.

The outer joint member 1 has a spherical inner surface 2, and the spherical inner surface 2 is provided with more than six curved ball grooves 3.

The inner joint member 11 has a spherical outer surface 12 on which the same number of curved ball grooves 13 as the ball grooves 3 are formed.

The center A ₁ of the ball groove 3 provided in the outer joint member 1 and the ball groove 13 formed in the inner joint member 11
The center A _{2 of the} is offset laterally equidistant from the joint center O ₀ .

The torque transmitting balls 21 are the outer joint members 1
Is assembled between the ball groove 3 and the ball groove 13 of the inner joint member 11 to transmit torque between the two members 1 and 11.

As shown in FIG. 3, the cage 31 has a spigot 3 having an inner diameter substantially equal to the outer diameter of the inner joint member 11.
2 is formed. In addition, the cage 31 is formed with a spherical outer surface 33 that is in contact with the spherical inner surface 2 of the outer joint member 1 and a spherical inner surface 34 that is in contact with the spherical outer surface 12 of the inner joint member 11.

Further, the cage 31 is formed with the same number of pockets 35 as the number of balls for accommodating the torque transmitting balls 21.

[0025] the center B ₁ spherical outer surface 33 formed in the cage 31, the center B ₂ spherical inner surface 34, the ball grooves 3,1
It is located outside the center of 3 and each center B ₁ ,
B ₂ is offset laterally equidistant from the joint center O ₀ .

In the constant velocity joint having the above-mentioned structure, when the joint takes an operating angle and transmits torque between the outer joint member 1 and the inner joint member 11, the torque transmission ball 21 moves to the position shown in FIG. As shown in (I), while moving in the shape of a figure 8, the amount of circumferential movement on the outer diameter side of the joint is larger than the amount of circumferential movement on the inner diameter side.

Even when the torque transmission balls 21 are assembled in the pockets 35 of the cage 31, the torque transmission balls 21 that are initially assembled have the same amount of movement on the outer diameter side as on the inner diameter side. The movement amount is larger than the movement amount of 8 and the movement amount in that case is larger than the movement amount of the torque transmission ball 21 at the time of torque transmission.

In the constant velocity joint as described above, assuming that the side surfaces of the pocket 35 formed in the cage 31 that face each other in the cage circumferential direction are parallel surfaces, the inner diameter side of the pillar portion formed between the pockets is, as described above. The spherical surface area is reduced, and the strength and durability of the cage are reduced.

In order to solve the above problem, as shown in FIG. 2 (I), a pair of side surfaces 36 of the pocket 35, which are opposed to each other in the cage circumferential direction, are formed into inclined surfaces which are widened toward the outer diameter side of the joint. ing.

Here, the side surface 36 may be a flat surface as shown in FIG. 2 (I) or may be a concave curved surface as shown in FIG. 2 (II).

As described above, when the pair of side surfaces 36 are formed into inclined surfaces, the spherical surface area on the inner diameter side of the column portion 37 formed between the pockets 35 is increased, and the strength and durability of the cage 31 are improved. be able to.

FIG. 4 shows each type of constant velocity joint that can employ the cage 31 having the pair of side surfaces 36 as inclined surfaces.

The type A constant velocity joint shown in FIG. 4 (I) has an outer joint member 1 on one side of the joint center O _0.
The center A ₁ of the ball groove 3 and the center B ₂ of the spherical inner surface 34 of the cage 31 are arranged inside thereof, and the joint center O ₀
To the other side, the center A of the ball groove 13 of the inner joint member 11
₂ and the center B ₁ of the spherical outer surface 33 of the cage 31 are arranged inside thereof.

The type B constant velocity joint shown in FIG. 4 (II) has a center B ₂ of the spherical inner surface 34 of the cage 31 on one side of the joint center O ₀ and a ball groove of the outer joint member 1 on the inside thereof. 3 the center a ₁ of place, the other side of the joint center O _0, the center B ₁ spherical outer surface 33 of the cage 31, and a center a ₂ of the ball groove 13 of the inner joint member 11 inside thereof It is arranged.

The type C constant velocity joint shown in FIG. 4 (III) is the constant velocity joint shown in FIG.

In the type D constant velocity joint shown in FIG. 4 (IV), the center B ₂ of the spherical inner surface 34 of the cage 31 is arranged on one side of the joint center O ₀ and the spherical outer surface of the cage 31 is arranged on the other side. The center B ₁ of 33 is arranged, and the center A ₁ of the ball groove 3 of the outer joint member ₁ and the center A ₂ of the ball groove 13 of the inner joint member 11 are provided on the joint center O ₀ .

The constant velocity joint of type E shown in FIG. 4 (V) has the center A ₁ of the ball groove 3 of the outer joint member ₁ and the spherical inner surface 34 of the cage 31 at the same position on one side of the joint center O _0. The center B ₂ of the joint and the center O _{0 of the} joint.
At the same position on the other side, the center A ₂ of the ball groove 13 of the inner joint member 11 and the center B ₁ of the spherical outer surface 33 of the cage 31.
And are arranged.

In any of the above constant velocity joints, when the outer joint member 1 and the inner joint member 11 form an operating angle to transmit torque, the torque transmitting balls move in the circumferential direction on the outer diameter side of the joint. The amount of movement is larger than the amount of movement in the circumferential direction on the inner diameter side, and moves in the shape of a figure 8. Therefore, it is possible to employ a cage 31 having a pair of side surfaces 36 facing each other in the circumferential direction of the pocket 35 as inclined surfaces.

[0039]

As described above, according to the present invention, when torque is transmitted between the outer joint member and the inner joint member at an operating angle, the torque transmitting ball incorporated in the pocket of the cage is connected to the outside of the joint. In a constant velocity joint that draws an 8-shape in which the amount of movement in the radial direction on the radial side is larger than the amount of movement in the circumferential direction on the inner diameter side, a pair of side surfaces of the pocket formed in the cage that face each other in the cage circumferential direction By forming the inclined surface that is widened and inclined in the outer diameter direction, it is possible to increase the spherical surface area of the pillar portion formed between the pockets on the inner diameter side. As a result, a cage having excellent strength and durability can be provided.

[Brief description of drawings]

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

FIG. 2 (I) is a sectional view showing an example of a pocket formed in the same cage, and (II) is a sectional view showing another example of the pocket.

FIG. 3 is a sectional view showing the above cage.

4 (I) to (V) are views showing various constant velocity joints in which the respective centers of the ball groove and the spherical inner and outer surfaces of the cage are offset from the joint center.

FIG. 5 is a sectional view showing a conventional constant velocity joint.

FIG. 6 is a diagram showing a movement of the ball when the constant velocity joint takes an operating angle to transmit torque.

FIG. 7 is a cross-sectional view showing an assembled state of the inner joint member to the cage.

FIG. 8 is a cross-sectional view showing an assembled state of the inner joint member to the cage.

FIG. 9 is a cage cross-sectional view in which each center of the spherical inner and outer surfaces is offset.

FIG. 10 is a diagram showing the movement of the torque transmission ball when an offset type cage in which the centers of the spherical inner and outer surfaces are offset is used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer joint member 2 Spherical inner surface 3 Ball groove 11 Inner joint member 12 Spherical outer surface 13 Ball groove 31 Cage 33 Spherical outer surface 34 Spherical inner surface 35 Pocket 36 Side surface

Claims (3)

[Claims] 1. A plurality of curved ball grooves are formed on a spherical inner surface of an outer joint member and a spherical outer surface of an inner joint member, and torque transmission balls are incorporated in ball grooves opposed to each other in a radial direction of the joint. A cage having a spherical outer surface and a spherical inner surface that are contact-guided to the spherical inner surface of the joint member and the spherical outer surface of the inner joint member is formed with a pocket for accommodating the torque transmission ball, and the center of the spherical outer surface of the cage and the spherical inner surface of the cage are formed. The center is offset to the left and right with respect to the center of the joint, the center of the ball groove of the outer joint member is offset in the joint center direction with respect to the center of the spherical outer surface, and the center of the ball groove of the inner joint member is In a fixed type constant velocity joint that is offset equidistantly in the direction of the joint center with respect to the center of the spherical inner surface, a cage of pockets formed in the cage A fixed type constant velocity joint, characterized in that a pair of side surfaces facing each other in the circumferential direction are inclined surfaces which are inclined with a spread toward the outer diameter side of the joint. 2. The fixed type constant velocity joint according to claim 1, wherein the side surface is a flat surface. 3. The fixed type constant velocity joint according to claim 1, wherein the side surface is a concave curved surface.