Fixed-type constant velocity universal joint

Patent metadata

Field	Value
Publication number	US-10260569-B2
Application number	US-201414899850-A
Country	US
Kind code	B2
Filing date	May 26, 2014
Priority date	Jun 26, 2013
Publication date	Apr 16, 2019
Grant date	Apr 16, 2019

Abstract

A fixed type constant velocity universal joint of a track groove crossing type has track grooves of an inner joint member formed so as to be mirror-image symmetrical with the paired track grooves of an outer joint member with respect to a joint center plane at an operating angle of 0°. The track grooves of both the joint members each have a length corresponding to a maximum operating angle required for a rear-wheel drive shaft. Further, each axial clearance between the inner joint member and the cage is set larger than an axial clearance formed by a ball track clearance between each of balls and each track groove.

First claim

The invention claimed is:

1. A fixed type constant velocity universal joint, comprising:
an outer joint member having a spherical inner peripheral surface in which a plurality of track grooves are formed so as to extend in an axial direction of the outer joint member;
an inner joint member having a spherical outer peripheral surface in which a plurality of track grooves are formed so as to be paired with the plurality of track grooves of the outer joint member;
balls for transmitting torque,
the balls being interposed between the plurality of track grooves of the outer joint member and the plurality of track grooves of the inner joint member, which are paired with each other; and

a cage having:
a spherical outer peripheral surface fitted to the spherical inner peripheral surface of the outer joint member; and
a spherical inner peripheral surface fitted to the spherical outer peripheral surface of the inner joint member,

wherein the plurality of track grooves of the outer joint member are each formed into an arc shape having a curvature center that is prevented from being offset in the axial direction with respect to a joint center, the plurality of track grooves of the outer joint member being inclined in a peripheral direction of the outer joint member with respect to a joint axial line and adjacent pairs of the plurality of track grooves of the outer joint member in the peripheral direction having inclination directions opposite to each other,
wherein the plurality of track grooves of the inner joint member are formed so as to be mirror-image symmetrical with the plurality of paired track grooves of the outer joint member with respect to a joint center plane at an operating angle of 0°,
wherein the plurality of track grooves of the outer joint member and the plurality of track grooves of the inner joint member each have a length corresponding to a maximum operating angle of 30°, and
wherein to allow absorption of axial vibration inputted to the fixed type constant velocity universal joint:
the outer joint member and the inner joint member allow relative displacement therebetween in the axial direction;
an axial clearance ΔSia 1 is formed between the inner joint member and the cage to axially separate the inner joint member and the cage from each other on an opening side of the outer joint member under a non-load state, and an axial clearance ΔSia 2 is formed between the inner joint member and the cage to axially separate the inner joint member and the cage from each other on an interior side of the outer joint member under the non-load state; and
each of the axial clearances ΔSia 1 and ΔSia 2 is larger than a sum of an axial clearance ΔTao, which is formed by a ball track clearance between one of the balls and an associated one of the track grooves of the outer joint member under the non-load state, and an axial clearance ΔTai, which is formed by a ball track clearance between one of the balls and an associated one of the track grooves of the inner joint member under the non-load state.

2. The fixed type constant velocity universal joint according to claim 1 , wherein the curvature center of each of the plurality of track grooves of the outer joint member and a curvature center of each of the plurality of track grooves of the inner joint member are arranged on the joint axial line.

3. The fixed type constant velocity universal joint according to claim 1 , wherein the curvature center of each of the plurality of track grooves of the outer joint member and a curvature center of each of the plurality of track grooves of the inner joint member are arranged at positions offset in a radial direction of each of the outer joint member and the inner joint member with respect to the joint axial line.

4. The fixed type constant velocity universal joint according to claim 1 , wherein a number of the balls is set to six, eight, ten, or twelve.

5. A fixed type constant velocity universal joint, comprising:
an outer joint member having a spherical inner peripheral surface in which a plurality of track grooves are formed so as to extend in an axial direction of the outer joint member;
an inner joint member having a spherical outer peripheral surface in which a plurality of track grooves are formed so as to be paired with the plurality of track grooves of the outer joint member;
balls for transmitting torque,
the balls being interposed between the plurality of track grooves of the outer joint member and the plurality of track grooves of the inner joint member, which are paired with each other; and

a cage having:
a spherical outer peripheral surface fitted to the spherical inner peripheral surface of the outer joint member; and
a spherical inner peripheral surface fitted to the spherical outer peripheral surface of the inner joint member,

wherein the plurality of track grooves of the outer joint member are each formed into an arc shape having a curvature center that is prevented from being offset in the axial direction with respect to a joint center, the plurality of track grooves of the outer joint member being inclined in a peripheral direction of the outer joint member with respect to a joint axial line and adjacent pairs of the plurality of track grooves of the outer joint member in the peripheral direction having inclination directions opposite to each other,
wherein the plurality of track grooves of the inner joint member are formed so as to be mirror-image symmetrical with the plurality of paired track grooves of the outer joint member with respect to a joint center plane at an operating angle of 0°,
wherein the plurality of track grooves of the outer joint member and the plurality of track grooves of the inner joint member each have a length corresponding to a maximum operating angle of 20°, and
wherein to allow absorption of axial vibration inputted to the fixed type constant velocity universal joint:
the outer joint member and the inner joint member allow relative displacement therebetween in the axial direction;
an axial clearance ΔSia 1 is formed between the inner joint member and the cage to axially separate the inner joint member and the cage from each other on an opening side of the outer joint member under a non-load state, and an axial clearance ΔSia 2 is formed between the inner joint member and the cage to axially separate the inner joint member and the cage from each other on an interior side of the outer joint member under the non-load state; and
each of the axial clearances ΔSia 1 and ΔSia 2 is larger than a sum of an axial clearance ΔTao, which is formed by a ball track clearance between one of the balls and an associated one of the track grooves of the outer joint member under the non-load state, and an axial clearance ΔTai, which is formed by a ball track clearance between one of the balls and an associated one of the track grooves of the inner joint member under the non-load state.

6. The fixed type constant velocity universal joint according to claim 5 , wherein the curvature center of each of the plurality of track grooves of the outer joint member and a curvature center of each of the plurality of track grooves of the inner joint member are arranged on the joint axial line.

7. The fixed type constant velocity universal joint according to claim 5 , wherein the curvature center of each of the plurality of track grooves of the outer joint member and a curvature center of each of the plurality of track grooves of the inner joint member are arranged at positions offset in a radial direction of each of the outer joint member and the inner joint member with respect to the joint axial line.

8. The fixed type constant velocity universal joint according to claim 5 , wherein a number of the balls is set to six, eight,

Assignees

• Hirukawa Hiroyasu
• Fujio Teruaki
• Ntn Toyo Bearing Co Ltd

Inventors

• Hirukawa Hiroyasu
• Fujio Teruaki

Classifications

• F16D3/2245 Primary

  where the groove centres are offset from the joint centre · CPC title

• F16D2003/22309

  Details of grooves · CPC title

• F16D2003/22303

  Details of ball cages · CPC title

• F16D3/223 Primary

  the rolling members being guided in grooves in both coupling parts · CPC title

• F16D3/224

  the groove centre-lines in each coupling part lying on a sphere · CPC title