Parking lock mechanism for a transmission

Patent metadata

Field	Value
Publication number	US-9869389-B2
Application number	US-201414392081-A
Country	US
Kind code	B2
Filing date	Mar 13, 2014
Priority date	Mar 15, 2013
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

A parking lock mechanism having a motor, an actuation shaft, an engagement cam, a release cam, a cam biasing member, a pawl member and a lock gear. The engagement cam has a first side, a second side and a perforation there through. An outer edge of the engagement cam has a contact portion and an engagement portion. The release cam has a first side, a second side and a perforation there through. An outer edge of the release cam has a release member and an engagement portion. The cam biasing member has a first end, a coil portion and a second end. The pawl member has a pivot perforation, an engagement end, a locking protuberance and a sensor protuberance. The pawl member is disposed adjacent the engagement cam and the release cam. The lock gear has a plurality of inner splines and outer teeth.

First claim

What is claimed is:

1. A parking lock mechanism, comprising:
a motor, an actuation shaft, an engagement cam, a release cam, a cam biasing member, a pawl member and a lock gear;
said engagement cam comprises a first side, a second side and a perforation formed there through, an outer edge of said engagement cam comprises a contact portion and an engagement portion, said engagement portion extends radially outward from said engagement cam;
said release cam comprises a first side, a second side and a perforation formed there through, an outer edge of said release cam comprises a release member and an engagement portion, said release member is tapered and extends radially outward from said release cam;
said cam biasing member comprises a first end, a coil portion and a second end;
said release cam engagement portion engages a second end of said cam biasing member;
said pawl member comprises a pivot perforation, an engagement end, a locking protuberance, and sensor protuberance, said pawl member is disposed adjacent said engagement cam and said release cam;
said lock gear comprises a plurality of inner splines and plurality of outer teeth;
wherein said engagement cam and said release cam are independently moveable with respect to one another.

2. A parking lock mechanism according to claim 1 , wherein said first side of said engagement cam is disposed against a step formed of said actuation shaft.

3. A parking lock mechanism according to claim 1 , wherein said second side of said engagement cam is disposed against said release cam.

4. A parking lock mechanism according to claim 1 , wherein said contact portion of said engagement cam has an increasing radius with respect to said perforation.

5. A parking lock mechanism according to claim 4 , wherein an initial radius R 1 of said contact portion of said engagement cam is substantially equal to a radius of a remaining portion of said engagement cam.

6. A parking lock mechanism according to claim 4 , wherein a final radius R 2 of said contact portion is greater than a radius of a remaining portion of said engagement cam.

7. A parking lock mechanism according to claim 1 , wherein said first side of said release cam is disposed adjacent said second side of said engagement cam.

8. A parking lock mechanism according to claim 1 , wherein said second side of said release cam is disposed against said cam biasing member.

9. A parking lock mechanism according to claim 1 , wherein said first end and said second end of said cam biasing member are both bent into a right angle.

10. A parking lock mechanism according to claim 1 , wherein said plurality of outer teeth of said lock gear are arranged in a circular array on an outer edge of said lock gear, said teeth are trapezoidal in shape and each extends radially from a remaining portion of said lock gear, a plurality of locking recesses are defined by the spaces between said teeth.

11. A parking lock mechanism according to claim 1 , wherein said pawl member pivots in a plane substantially parallel to a plane each of said engagement cam and said release cam are able to rotate within.

12. The parking lock mechanism according to claim 1 , wherein said cam biasing member is coaxial with said actuation shaft.

13. The parking lock mechanism according to claim 1 , wherein said engagement cam and said release cam are axially offset from one another on said actuation shaft.

Assignees

• Dana Automotive Systems Group

Inventors

• Rhoades Douglas R
• Wright Robert
• Gries Aaron
• Miller David
• Hahn Adam

Classifications

• F16H63/3433 Primary

  Details of latch mechanisms, e.g. for keeping pawls out of engagement · CPC title

• F16H63/3416 Primary

  Parking lock mechanisms or brakes in the transmission · CPC title

• F16H63/3466

  using electric motors · CPC title

• B60Y2400/414

  Ramp or cam mechanisms · CPC title