Claw shifting element comprising a sliding sleeve for an automatic transmission of a motor vehicle

Patent metadata

Field	Value
Publication number	US-9470274-B2
Application number	US-201414484763-A
Country	US
Kind code	B2
Filing date	Sep 12, 2014
Priority date	Sep 12, 2013
Publication date	Oct 18, 2016
Grant date	Oct 18, 2016

Abstract

A claw shifting element for a motor vehicle transmission includes a sliding sleeve that is axially fixed in its two end positions by frictional locking.

First claim

The invention claimed is:

1. A claw shifting element for a motor vehicle transmission, comprising:
a sliding sleeve that is axially movable between opposite end positions;
the sliding sleeve axially fixable in each of the end positions by frictional locking of the sliding sleeve;
a hydraulically actuated piston engaged with the sliding sleeve to move the sliding sleeve between the opposite end positions; and
a stationary component that engages against the sliding sleeve and provides the friction locking of the sliding sleeve at each of the end positions in an unpressurized state of the piston, wherein an axial force acting upon the sliding sleeve upon actuation of the piston being greater than a static friction force between the sliding sleeve and the stationary component.

2. The claw shifting element as in claim 1 , wherein the stationary component comprises an elastomer component.

3. The claw shifting element as in claim 2 , wherein the elastomer component has a crown-shape.

4. The claw shifting element as in claim 1 , further comprising an actuating fork that engages with fingers in a groove defined in the sliding sleeve, the actuating fork moved by a fork piston that is axially parallel to the sliding sleeve, the fork piston movable between end positions, and further comprising a reset device at each end position of the fork piston that partially resets the fork piston after withdrawal of actuating pressure from the fork piston.

5. The claw shifting element as in claim 4 , wherein the reset devices comprise spring elements or elastomer buffers.

6. The claw shifting element as in claim 5 , wherein the reset devices comprise pressure springs.

7. The claw shifting element as in claim 6 , wherein the pressure springs are preloaded to achieve a defined partial resetting of the fork piston.

8. The claw shifting element as in claim 4 , wherein the reset devices are elastomer buffers, the fork piston further comprising sealing elements that are formed as one piece with the elastomer buffers.

9. A claw shifting element for a motor vehicle transmission, comprising:
a sliding sleeve that is axially movable between opposite end positions;
the sliding sleeve axially fixable in each of the end positions by frictional locking of the sliding sleeve; and
further comprising an actuating piston engaged with the sliding sleeve by way of a projection that engages within a groove in the sliding sleeve such that axial backlash is provided between the projection and the groove, the actuating piston arranged within a housing and being movable between end positions, and further comprising a reset device at each end position of the actuating piston that partially resets the actuating piston after withdrawal of actuating pressure from the actuating piston.

10. The claw shifting element as in claim 9 , wherein the reset devices comprise spring elements or elastomer buffers.

11. The claw shifting element as in claim 9 , wherein the reset devices comprise spring elements at the end positions of the actuating piston that are preloaded to achieve a defined partial resetting of the actuating piston.

12. The claw shifting element as in claim 11 , wherein the spring elements are disk springs or wave springs.

13. The claw shifting element as in claim 9 , wherein the reset devices are elastomer buffers, the actuating piston further comprising sealing elements that are formed as one piece with the elastomer buffers.

14. The claw shifting element as in claim 13 , further comprising a housing in which the sliding sleeve is contained, wherein the actuating piston, the sealing elements, and the elastomer buffers are pre-assembled in a casing, the casing pressed into the housing.

Assignees

• Zahnradfabrik Friedrichshafen

Inventors

• Ziemer Peter
• Brehmer Martin
• Margraf Christoph
• Schneider Benjamin

Classifications

• F16D11/14 Primary

  with clutching members movable only axially (F16D11/02, F16D11/08 take precedence) · CPC title

• F16D25/061

  the clutch having interengaging clutch members · CPC title

• Y10T74/20177

  Particular element [e.g., shift fork, template, etc.] · CPC title

• F16D2011/006

  Locking or detent means, i.e. means to keep the clutch in engaged condition · CPC title