JPH09196082A - Universal coupling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a holder, which is arranged between the inner bottom surface of a case and an end surface of a shaft, in the non-contact condition in relation to the case at the time of oscillating a universal coupling so as to prevent the abrasion of the holder. SOLUTION: This universal coupling has a cylindrical case having a bottom, which is fitted in a bearing fitting hole of a yoke, a cross shaft, of which shaft part is fitted in this case, plural needle-shaped rolls arranged between the cylindrical inner peripheral surface of the case and the peripheral surface of the shaft part of the cross shaft, a disc-shaped holder provided between the inner bottom surface of the case and the end surface of the shaft part of the cross shaft freely to be rotated, and plural balls, which are held in plural pockets formed in the holder freely to be rotated and which hold the holder in the non-contact condition in relation to the inner bottom surface of the case and the end surface of the shaft part. An outer peripheral edge 1b of the bottom part of the case 1 is formed into a stepped part 14 close to the end surface 10 side of the shaft part in comparison with a central part 1a of the bottom part, and the plural pockets 12 of the holder 11 are opened at the peripheral edge of the holder so that a part of the ball 13 is always projected from the peripheral edge of the holder, and the holder 11 and the case 1 are maintained in the non-contact condition in the radial direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a universal joint used for a steering shaft of an automobile.

[0002]

2. Description of the Related Art Conventionally, Japanese Patent Laid-Open No. 2-180316 has been known as a universal joint having a structure for reducing swing torque. That is, as shown in FIGS. 3 and 4, this is a bottomed cylindrical case 32 fitted in the bearing fitting hole 29 of the yoke 33, and a cross in which the shaft portion 31 is fitted in the case 32. The shaft 30, the cylindrical inner peripheral surface 38 of the case 32, and the outer peripheral surface 39 of the shaft portion 31 of the cross shaft 30.
A plurality of needle rollers 34 arranged between them, a disc-shaped cage 35 rotatably provided between the inner bottom surface 37 of the case 32 and the end surface 40 of the shaft portion 31 of the cross shaft 30, and A plurality of balls 36 that are rotatably held in a plurality of pockets 41 formed in the cage 35 and that keep the cage 35 in non-contact with the inner bottom surface 37 of the case 32 and the end surface 40 of the shaft portion 31.
And The pocket 41 is used for the retainer 3
5 is formed inward in the radial direction by a certain distance from the outer peripheral edge 42, and the outer peripheral edge 42 is not open. In addition, needle roller 3
4 is arranged such that its end portion is axially outward from the end surface 40 of the shaft portion 31 of the cross shaft 30, and faces the outer peripheral edge 42 of the cage 35.

[0003]

The universal joint shown in FIG. 3 has the outer peripheral edge 42 of the cage 35 and the needle rollers 34.
Since the end portions of the cage are opposed to each other, the cage 35 and the needle rollers 34 may come into contact with each other when the universal joint swings, and the cage 35 may be worn and damaged. Further, since the end portion of the needle roller 34 projects outward in the axial direction from the end surface 40 of the shaft portion 31 of the cross shaft 30, the needle roller 34 may be damaged by edge loading of the shaft portion 31. . Therefore, an object of the present invention is to prevent wear of a cage, and another object is to provide a universal joint in which an edge load does not act on a needle roller.

[0004]

As means for solving the above problems, as a means for solving the above problems, a bottomed cylindrical case fitted in a bearing fitting hole of a yoke and a cross shaft having a shaft portion fitted in the case A plurality of needle rollers arranged between the cylindrical inner peripheral surface of the case and the shaft outer peripheral surface of the cross shaft, and rotatably provided between the inner bottom surface of the case and the shaft end surface of the cross shaft. And a plurality of balls that are rotatably held in a plurality of pockets formed in the cage and that keep the cage in non-contact with the inner bottom surface of the case and the end surface of the shaft portion. In the universal joint, the outer peripheral edge portion of the bottom portion of the case is a stepped portion that is closer to the shaft end face side than the center portion of the bottom portion, and the plurality of pockets of the cage are opened at the outer peripheral edge of the cage so that the ball The part is held in the pocket so that it always protrudes from the outer peripheral edge of the cage. , Characterized in that the retainer and the said casing is kept non-contact in the radial direction by the ball. Further, the inner surface of the stepped portion of the case is characterized in that the needle roller has its end face maintained at substantially the same radial position as the end face of the shaft portion of the cross shaft. Furthermore,
It is characterized in that the plurality of balls are arranged at equal intervals around the circumference of the cage.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a cylindrical shell case having a bottom, which is fitted in a bearing fitting hole 3 of a yoke 2, and a shaft portion 5 of a cross shaft 4 is fitted in the case 1. The cylindrical inner peripheral surface 6 of the case 1 and the cross shaft 4
A plurality of needle rollers 8 are arranged between the outer peripheral surface 7 of the shaft portion 5. Further, the inner bottom surface 9 of the case 1 and the cross shaft 4 are
Between the end surfaces 10 of the shaft portions 5 of the disk holder 5, a disk-shaped cage 11 rotatably provided and a plurality of pockets 12 formed in the cage 11 are rotatably held, and the cage 11 is held. An inner bottom surface 9 of the case 1 and a ball 13 that is kept in non-contact with the end surface 10 of the shaft portion 5 are arranged. Reference numeral 16 is a guide flange for the needle roller 8 formed at the end of the case 1.

The case 1 is formed with a stepped portion 14 whose bottom outer peripheral edge portion 1b is closer to the shaft end face 10 side than the bottom central portion 1a. Further, the plurality of pockets 12 of the retainer 11 can be better understood in FIG.
A part of the ball 13 is opened at the outer peripheral edge 11a of the cage, and a part of the ball 13 is partly opened by the opening portion 15a.
The balls 13 are held in the pockets 12 so as to always protrude in the radial direction from a, and the cage 11 and the case 1 are kept in the radial non-contact by the balls 13.

The retainer 11, the ball 13 and the case 1
With the configuration, when the universal joint swings, the balls 13 come into contact with the side surface 14a of the stepped portion 14 of the case 1,
There is no contact of the cage 11 with the case 1, and there is no wear of the cage 11.

Further, due to the inner bottom surface 14b of the stepped portion 14 of the case 1, the end surface 8a of the needle roller 8 has a cross shaft 4a.
The shaft end face 10 is maintained at the same position in the axial direction. As a result, the needle roller 8 is not subjected to edge loading by the shaft portion 5 of the cross shaft 4, so that the needle roller 8 is not damaged.

Further, as shown in FIG. 2, the balls 13 are arranged on the cage 11 in a circumferentially equidistant manner, for example, in three equidistant manners. As a result, stable rocking torque can be obtained.

[0010]

According to the present invention, when the universal joint swings,
Even if the cage moves, the balls can be prevented from coming into contact with the case, so that the cage is not worn or damaged.

[Brief description of the drawings]

FIG. 1 is a partial vertical sectional view of an embodiment according to the present invention.

FIG. 2A is a plan view of a cage in which the balls in FIG. 1 are retained. 2B is a sectional view taken along line XX of FIG. 2A.

FIG. 3 is a partial vertical sectional view of a conventional universal joint.

FIG. 4 is a perspective view of a retainer holding the balls in FIG.

[Explanation of symbols]

 1 Bottomed Cylindrical Case 1a Bottom Central Part 1b Bottom Outer Perimeter 2 Yoke 3 Bearing Fitting Hole 4 Cross Shaft 5 Shaft 6 Cylindrical Inner Surface 7 Shaft Outer Surface 8 Needle Roller 9 Case Inner Bottom 10 Shaft End face 11 Cage 11a Outer peripheral edge 12 Pocket 13 Ball 14 Stepped portion 15 Opening portion

Front page continued (72) Inventor Junya Watanabe 3-5-8 Minamisenba, Chuo-ku, Osaka City Koyo Seiko Co., Ltd.

Claims (3)

[Claims] 1. A bottomed cylindrical case fitted in a bearing fitting hole of a yoke, a cross shaft having a shaft portion fitted in the case, a cylindrical inner peripheral surface of the case, and the cross shaft. A plurality of needle rollers disposed between the outer peripheral surfaces of the shaft portion, a disc-shaped cage rotatably provided between the inner bottom surface of the case and the shaft end surface of the cross shaft, and the cage. In a universal joint that is rotatably held in a plurality of formed pockets and that has a plurality of balls that keep the cage in contact with the inner bottom surface of the case and the end surface of the shaft portion, the outer peripheral edge portion of the bottom portion of the case is the bottom portion. The stepped portion is closer to the end face side of the shaft portion than the central portion, and the plurality of pockets of the cage are opened at the outer peripheral edge of the retainer so that a part of the balls always protrudes from the outer peripheral edge of the retainer. And the cage and the case are held by the balls in the radial direction. Universal joint characterized by being kept in non-contact with. 2. The inner peripheral surface of the stepped portion of the case maintains the end surface of the needle roller at substantially the same position in the radial direction as the end surface of the shaft portion of the cross shaft. Universal joint. 3. The universal joint according to claim 1, wherein the plurality of balls are arranged at equal intervals in a circumference of the cage.