Decoupler clutch engagement surface with selected surface finish

Patent metadata

Field	Value
Publication number	US-10670082-B2
Application number	US-201715617707-A
Country	US
Kind code	B2
Filing date	Jun 8, 2017
Priority date	Aug 19, 2013
Publication date	Jun 2, 2020
Grant date	Jun 2, 2020

Abstract

In an aspect, the invention is directed to a clutched device that includes a clutch input member, a clutch output member, and a wrap spring clutch. The wrap spring clutch is engageable with the clutch input member and the clutch output member and has a radially outer surface and a radially inner surface. One of the radially outer and inner surfaces is engageable with a clutch engagement surface on one of the clutch input member and the clutch output member. The clutch engagement surface has a surface finish that includes peaks and valleys, wherein the peaks engage the wrap spring clutch and each have a selected width.

First claim

The invention claimed is:

1. A clutched device, comprising:
a clutch input member;
a clutch output member;
a wrap spring clutch that is engageable with the clutch input member and the clutch output member and which has a radially outer surface and a radially inner surface, wherein one of the radially outer and inner surfaces is engageable with a clutch engagement surface on one of the clutch input member and the clutch output member; and
a volume of lubricant positioned to lubricate the wrap spring clutch and the clutch engagement surface;
wherein the clutch engagement surface has a surface finish that includes peaks and valleys, wherein the peaks engage the wrap spring clutch and a majority of the peaks have a width between about 20 and about 300 microns.

2. A clutched device as claimed in claim 1 , wherein said majority of peaks have a peak-to-peak a pitch of about 100 to about 400 microns.

3. A clutched device as claimed in claim 2 , wherein said majority of peaks each have a height of about 3 to about 15 microns.

4. A clutched device as claimed in claim 1 , wherein the clutch engagement surface is an inner surface of the clutch input member that engages a radially outer surface of the wrap spring clutch.

5. A clutched device as claimed in claim 1 , wherein the clutch engagement surface is made from a steel that is nitrided.

6. A clutched device as claimed in claim 1 , wherein said majority of peaks: have a peak-to-peak pitch of about 100 to about 400 microns, have a height of about 3 to about 15 microns, and the ratio of the width of each peak to a width of each valley adjacent each peak is between about 0.2:1 and about 3:1.

7. A decoupler, comprising:
a decoupler input member;
a decoupler output member;
a wrap spring clutch and an isolation spring that act in series in a torque path between the decoupler input member and the decoupler output member, wherein the wrap spring clutch has a radially inner surface and a radially outer surface, wherein at least one of the radially inner and outer surfaces engages a clutch engagement surface of the decoupler; and
a volume of lubricant positioned to lubricate the wrap spring clutch and the clutch engagement surface,
wherein the at least one clutch engagement surface has a surface finish that includes peaks and valleys, wherein the peaks engage the wrap spring clutch and a majority of the peaks have a width of between about 20 and about 300 microns.

8. A decoupler as claimed in claim 7 , wherein the clutch engagement surface is on the decoupler input member.

9. A decoupler as claimed in claim 7 , further comprising a sleeve positioned to receive torque from the isolation spring and to transmit torque to the wrap spring clutch and wherein the clutch engagement surface is on the sleeve.

10. A decoupler as claimed in claim 7 , wherein said majority of peaks have a peak-to-peak a pitch of about 100 to about 400 microns.

11. A decoupler as claimed in claim 10 , wherein said majority of peaks each have a height of about 3 to about 15 microns.

12. A decoupler as claimed in claim 7 , wherein said majority of peaks have: a peak-to-peak pitch of about 100 to about 400 microns, a height of about 3 to about 15 microns, and the ratio of the width of each peak to a width of each valley adjacent each peak is between about 0.2:1 and about 3:1.

Assignees

• Litens Automotive Inc

Inventors

• Hurry Evan J

Classifications

• F16D13/74

  Features relating to lubrication · CPC title

• F16H7/18

  Means for guiding or supporting belts, ropes, or chains (construction of pulleys F16H55/36) · CPC title

• F16D13/08

  with a helical band or equivalent member, which may be built up from linked parts, with more than one turn embracing a drum or the like, with or without an additional clutch actuating the end of the band (F16D13/02 takes precedence; {similar slip couplings F16D7/022; similar clutches electromagnetically actuated F16D27/025, F16D27/105} ; similar free-wheel clutches F16D41/20; similar brakes F16D49/02) · CPC title

• F16D13/12 Primary

  with an expansible band or coil co-operating with the inner surface of a drum or the like (F16D13/02 takes precedence; similar brakes F16D51/02) · CPC title

• B60K25/02 Primary

  directly from an engine shaft · CPC title