Coupling pin anti-rotation for a switchable roller finger follower

Patent metadata

Field	Value
Publication number	US-9920659-B2
Application number	US-201615146943-A
Country	US
Kind code	B2
Filing date	May 5, 2016
Priority date	May 5, 2016
Publication date	Mar 20, 2018
Grant date	Mar 20, 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. The coupling pin, located on one of the levers, has a first locking surface, and includes at least one coupling pin-side anti-rotation flat; the other lever, with a second locking surface, is configured with at least one lever-side anti-rotation flat. The at least one lever-side anti-rotation flat slidably guides the at least one coupling pin-side anti-rotation flat such that the first locking surface is aligned with the second locking surface throughout longitudinal displacement of the coupling pin within a coupling pin bore. The coupling pin anti-rotation arrangement is adaptable to various switchable roller finger follower designs that incorporate different valve lift strategies and lever configurations.

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,
at least one coupling pin-side anti-rotation flat; 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 at least one coupling pin-side anti-rotation flat is slidably guided by an at least one lever-side anti-rotation flat, located on the other of the inner lever or the outer lever.

2. The switchable roller finger follower of claim 1 , wherein the at least one lever-side anti-rotation flat includes first and second lever-side anti-rotation flats and the at least one coupling pin-side anti-rotation flat includes first and second coupling pin-side anti-rotation flats.

3. The switchable roller finger follower of claim 1 , wherein the at least one lever-side anti-rotation flat and the at least one coupling pin-side anti-rotation flat have a space defined therebetween that ranges from 0.010 to 0.500 mm.

4. The switchable roller finger follower of claim 1 , wherein the first and second locking surfaces have a space defined therebetween that ranges from 0.010 to 0.300 mm.

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

6. The switchable roller finger follower of claim 1 , wherein the at least one lever-side anti-rotation flat is generally L-shaped.

7. The switchable roller finger follower of claim 1 , wherein the at least one coupling pin-side anti-rotation flat is slidably guided by the at least one lever-side anti-rotation flat in the coupling pin direction while in the first locked position, and the at least one coupling pin-side anti-rotation flat is slidably guided by the at least one lever-side anti-rotation flat in the lost motion direction while in the second, unlocked position.

8. The switchable roller finger follower of claim 1 , wherein the at least one lever-side anti-rotation flat remains in constant contact with the at least one coupling pin-side anti-rotation flat.

9. 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.

10. The switchable roller finger follower of claim 9 , wherein the first valve lift mode is a full valve lift mode and the second valve lift mode is a no valve lift mode.

11. The switchable roller finger follower of claim 10 , wherein the second locking surface and the at least one lever-side anti-rotation flat are located on the inner lever and the coupling pin bore is located on the outer lever.

12. The switchable roller finger follower of claim 1 , further comprising a cam roller follower arranged on the inner lever.

13. 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.

14. The switchable roller finger follower of claim 9 , wherein the first valve lift mode is a high valve lift mode and the second valve lift mode is a low valve lift mode.

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

16. The switchable roller finger follower of claim 1 , further comprising a resilient element in contact with the coupling pin, the resilient element 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.

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

Assignees

• Schaeffler Technologies Ag

Inventors

• Ahmed Faheem
• Foster Colin

Classifications

• F01L13/0036

  the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction · CPC title

• F01L1/185

  Overhead end-pivot rocking arms · CPC title

• F16H53/06 Primary

  Cam-followers (F16H53/08 takes precedence) · CPC title

• F01L2001/186

  Split rocking arms, e.g. rocker arms having two articulated parts and means for varying the relative position of these parts or for selectively connecting the parts to move in unison · CPC title

• F01L13/0005

  Deactivating valves · CPC title