Coupling pin anti-rotation for a switchable roller finger follower

Patent metadata

Field	Value
Publication number	US-9903233-B2
Application number	US-201615215647-A
Country	US
Kind code	B2
Filing date	Jul 21, 2016
Priority date	Jul 21, 2016
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

A coupling pin anti-rotation arrangement is provided for a switchable roller finger follower within a valve train of an internal combustion engine capable of switching between at least two valve lift modes. The switchable roller finger follower includes an inner lever, an outer lever, a coupling pin, and an anti-rotation clip. The coupling pin, located on one of the inner or outer levers, has a first locking surface, and a first, and preferably, second coupling pin-side anti-rotation flat. The coupling pin moves longitudinally within a coupling pin bore to a first, locked position and a second, unlocked position. The anti-rotation clip has a first and, preferably, second clip-side finger to slidably guide the first and second coupling pin-side anti-rotation flats to ensure alignment of the first locking surface with a second locking surface, located on the other of the inner lever or the outer lever, during all modes of operation.

First claim

What is claimed is:

1. A switchable roller finger follower comprising:
an inner lever having first and second ends;
an outer lever having:
two outer arms that extend along longitudinal sides of the inner lever; and,
a third end mounted for pivoting movement at the first end of the inner lever by a pivot axle;

a coupling pin arranged to move longitudinally within a coupling pin bore located on one of the inner lever or the outer lever on an end opposite from the pivot axle, the coupling pin having:
a coupling projection with a first locking surface; and,
a first coupling pin-side anti-rotation flat; and,

an anti-rotation clip arranged on a same one of the inner lever or the outer lever as the coupling pin bore, the anti-rotation clip having a first clip-side finger at a locking end; and,
the coupling pin is moveable from a first, locked position with the first locking surface engaged with a second locking surface located on the other of the inner lever or the outer lever, to a second, unlocked position where the first locking surface is not engaged with the second locking surface, and the first coupling pin-side anti-rotation flat is slidably guided by the first clip-side finger.

2. The switchable roller finger follower of claim 1 , wherein the first coupling pin-side anti-rotation flat is guided by a guide surface of the first clip-side finger.

3. The switchable roller finger follower of claim 1 , further comprising a second clip-side finger on the anti-rotation clip and a second coupling pin-side anti-rotation flat on the coupling pin, the second coupling-pin side anti-rotation flat being slidably guided by the second clip-side finger as the coupling pin moves between the first and second positions.

4. The switchable roller finger follower of claim 3 , wherein the first and second clip-side fingers are configured with guide surfaces that face one another and guide oppositely located first and second coupling pin-side anti-rotation flats.

5. The switchable roller finger follower of claim 1 , wherein the first and second locking surfaces have a space defined therebetween that ranges from 0.001 to 0.300 mm.

6. The switchable roller finger follower of claim 1 , wherein the first clip-side finger is engaged with a locking end of a coupling pin bore housing.

7. The switchable roller finger follower of claim 1 , wherein the anti-rotation clip has at least one attachment hook at an end opposite the first clip-side finger.

8. The switchable roller finger follower of claim 7 , wherein the at least one attachment hook is engaged with an end of a coupling pin bore housing opposite a locking end.

9. The switchable roller finger follower of claim 8 , wherein the anti-rotation clip is elastically deflectable for engagement with the coupling pin bore housing.

10. The switchable roller finger follower of claim 1 , wherein the first and second locking surfaces are formed as flats.

11. The switchable roller finger follower of claim 1 , wherein the first coupling pin-side anti-rotation flat is slidably guided by the first clip-side finger in the first, locked and the second, unlocked positions.

12. The switchable roller finger follower of claim 1 , wherein the first clip-side finger remains in constant contact with the first coupling pin-side anti-rotation flat.

13. The switchable roller finger follower of claim 1 , wherein the first, locked position defines a first valve lift mode and the second, unlocked position defines a second valve lift mode.

14. The switchable roller finger follower of claim 13 , wherein the first valve lift mode is a full valve lift mode and the second valve lift mode is a no valve lift mode.

15. The switchable roller finger follower of claim 14 , wherein the second locking surface is located on the inner lever and the coupling pin bore and anti-rotation clip are located on the outer lever.

16. The switchable roller finger follower of claim 13 , wherein the first valve lift mode is a high valve lift mode and the second valve lift mode is a low valve lift mode.

17. The switchable roller finger follower of claim 16 , wherein the second locking surface is located on the outer lever and the coupling pin bore and anti-rotation clip are located on the inner lever.

18. The switchable roller finger follower of claim 1 , further comprising a valve interface configured on the third end and a pivot interface configured on a fourth end of the outer lever.

19. The switchable roller finger follower of claim 1 , further comprising a spring in contact with the coupling pin, the spring having a first compressed length in the first locked position and a second compressed length in the second unlocked position, wherein the first compressed length is greater than the second compressed length.

20. The switchable roller finger follower of claim 1 , further comprising at least one lost motion spring arranged between the inner lever and the outer lever.

Assignees

• Schaeffler Technologies Ag

Inventors

• Ahmed Faheem
• Foster Colin

Classifications

• F01L1/185

  Overhead end-pivot rocking arms · CPC title

• F01L2301/00

  Using particular materials · CPC title

• F01L13/0005 Primary

  Deactivating valves · CPC title

• F01L1/08

  Shape of cams · CPC title

• F01L2001/467

  Lost motion springs · CPC title