Spline slip constant velocity joint

Patent metadata

Field	Value
Publication number	US-11242896-B2
Application number	US-201816201629-A
Country	US
Kind code	B2
Filing date	Nov 27, 2018
Priority date	Jul 19, 2017
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

A constant velocity ball joint uses a star shaped sleeve with a splined connection to its shaft. The sleeve is longitudinally retained on its shaft using a retaining ring in an outwardly facing groove of the shaft. The star shaped sleeve has a 30° assembly assist chamfer angle on one side, as well as a 45° transition chamfer angle and a 65° ramp chamfer angle facing the opposite direction. These angles control the diameter of the retaining ring as it is compressed inward into the groove during assembly and disassembly. The star shaped sleeve can be used in a dynamic length CV joint, with the splines of a configuration that allows longitudinal sliding of the sleeve on the shaft, so the shell of the dynamic length CV joint still can be of the spherical race type.

First claim

The invention claimed is:

1. A constant velocity joint comprising:
a shaft having an outwardly facing groove on a distal end of the shaft;
a star shaped sleeve having a splined connection around the shaft for transmission of torque between the shaft and the sleeve, the sleeve having a periphery providing a plurality of inner races, the splined connection allowing the star shaped sleeve to slide axially on the shaft at a location proximal to the groove while transmitting torque;
a shell with a star shaped recess providing a corresponding plurality of outer races;
a plurality of balls riding between the inner races and the outer races for transmission of torque between the sleeve and the shell during angular articulation of the shaft relative to the shell; and
a retaining ring positionable within the groove for use in securing the sleeve to the shaft while permitting the sleeve to slide axially on the shaft;

wherein the sleeve comprises an assembly chamfer surface which can bias the retaining ring inward into the groove during assembly of the sleeve onto the shaft, and a disassembly chamfer surface having a different profile than the assembly chamfer surface and which can bias the retaining ring inward into the groove during disassembly of the sleeve off of the shaft, with neither the assembly chamfer surface nor the disassembly chamfer surface contacting the retaining ring during working of the constant velocity joint.

2. The constant velocity joint of claim 1 , wherein the disassembly chamfer surface comprises:
a transition chamfer surface angled at a transition chamfer angle relative to a longitudinal direction that the sleeve slides onto and off of the shaft during assembly and disassembly; and
a ramp chamfer surface angled at a ramp chamfer angle relative to the longitudinal direction that the sleeve slides onto and off of the shaft during assembly and disassembly, wherein the ramp chamfer angle is greater than the transition chamfer angle.

3. The constant velocity joint of claim 2 , wherein the assembly chamfer surface is angled at an assembly assist chamfer angle relative to a longitudinal direction that the sleeve slides onto and off of the shaft during assembly and disassembly, wherein the transition chamfer angle is greater than the assembly assist chamfer angle.

4. The constant velocity joint of claim 3 , wherein the ramp chamfer angle is greater than 45°.

5. The constant velocity joint of claim 4 , wherein the assembly assist chamfer angle is less than 45°.

6. The constant velocity joint of claim 5 , wherein the ramp chamfer angle is 65°, wherein the transition chamfer angle is 45°, and wherein the assembly assist chamfer angle is 30°.

7. The constant velocity joint of claim 3 , wherein the assembly chamfer surface, the transition chamfer surface and the ramp chamfer surface are all conical.

8. The constant velocity joint of claim 2 , wherein the sleeve further comprises a slide surface between the transition chamfer surface and the ramp chamfer surface.

9. The constant velocity joint of claim 8 , wherein the slide surface has an inner diameter which is less than a free state outer diameter of the retaining ring.

10. The constant velocity joint of claim 1 , wherein both the inner races and the outer races define a spherical profile about a pivot center of the joint.

11. The constant velocity joint of claim 1 , further comprising a ball cage between the sleeve and the shell, the ball cage holding the balls within the space between the inner and outer races.

12. The constant velocity joint of claim 1 , wherein the retaining ring has a free state outer diameter which is greater than an outer diameter of the groove, and wherein the retaining ring has a free state inner diameter which is less than an outer diameter of the groove and greater than an inner diameter of the groove, with the retaining ring being in its free state during working of the constant velocity joint.

13. The constant velocity joint of claim 12 , wherein the retaining ring is formed of wire having a circular cross-section, with a diameter of the wire being smaller than a width of the groove, wherein the disassembly chamfer surface comprises:
a transition chamfer surface angled at a transition chamfer angle relative to a longitudinal direction that the sleeve slides onto and off of the shaft during assembly and disassembly, the transition chamfer surface being at a radius from an axis of the shaft such that during disassembly the transition chamfer surface centers the retaining ring relative to the shaft.

14. The constant velocity joint of claim 1 , wherein the splined connection has wide angle contact faces, with angles between adjacent contact faces which transmit torque in a forward direction and contact faces which transmit torque in a reverse direction being in the range of 60° to 135°.

15. The constant velocity joint of claim 14 , wherein the wide angle contact faces are separated by inner faces which do not transmit torque and by outer faces which do not transmit torque.

16. A method of disassembly of a constant velocity joint comprising:
longitudinally advancing a star shaped sleeve toward the end of a shaft, the star shaped sleeve having a splined connection around the shaft for transmission of torque between the shaft and the sleeve, the sleeve having a periphery providing a plurality of inner races, the sleeve being within a shell with a star shaped recess providing a corresponding plurality of outer races, with a plurality of balls riding between the inner races and the outer races for transmission of torque between the sleeve and the shell during angular articulation of the shaft relative to the shell, the shaft having an outwardly facing groove, with a retaining ring within the groove, such that the longitudinal advancement causes a transition chamfer surface of the sleeve to contact and center the retaining ring relative to the groove and the shaft, the transition chamfer surface having a transition chamfer angle relative to the direction of longitudinal advancement;
further advancing the sleeve toward the end of the shaft, until the retaining ring contacts a ramp chamfer surface of the sleeve, the ramp chamfer surface being angled at a ramp chamfer angle relative to the direction of longitudinal advancement, wherein the ramp chamfer angle is greater than the transition chamfer angle; and
further advancing the sleeve toward the end of the shaft such that the ramp chamfer surface biases and compresses the retaining ring inwardly into the groove.

17. The method of claim 16 , wherein, when the ramp chamfer surface biases and compresses the retaining ring inwardly into the groove, the retaining ring has a circumferential gap which is smaller than a free state circumferential gap of the retaining ring.

Assignees

• Zhejiang Cfmoto Power Co Ltd

Inventors

• Cheng Fuying
• Kuang Zhenxiang
• Li Jiajun

Classifications

• F16D3/224 Primary

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

• F16D3/227

  the joints being telescopic · CPC title

• F16D2003/22313

  Details of the inner part of the core or means for attachment of the core on the shaft · CPC title

• F16D2001/103

  the torque is transmitted via splined connections · CPC title

• F16D3/223 Primary

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