Sliding contact for electrically actuated rocker arm

Patent metadata

Field	Value
Publication number	US-10731518-B2
Application number	US-201916460886-A
Country	US
Kind code	B2
Filing date	Jul 2, 2019
Priority date	Nov 25, 2015
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

A valvetrain for an internal combustion engine of the type that has a combustion chamber, a moveable valve having a seat formed in the combustion chamber, and a camshaft includes a rocker arm assembly, a pivot providing a fulcrum for a rocker arm of the rocker arm assembly, and a latch assembly. An electrical device mounted to the rocker arm assembly receives power or communicates through a circuit that includes an electrical connection formed by abutment between surfaces of two distinct parts. The rocker arm assembly is operative to move one of the two abutting surfaces relative to the other in response to actuation of the cam follower. Forming an electrical connection through abutting surfaces that are free to undergo relative motion may reduce or eliminate the need to run wires to a mobile portion of the rocker arm assembly.

First claim

The invention claimed is:

1. A valvetrain for an internal combustion engine of a type that has a combustion chamber, a moveable valve having a seat formed in the combustion chamber, and a camshaft, the valvetrain comprising:
a rocker arm assembly comprising a rocker arm and a cam follower configured to engage a cam mounted on the camshaft as the camshaft rotates; and
an electrical circuit comprising an electrical device mounted to the rocker arm;
wherein the electrical circuit includes an electrical connection made by abutment between a first surface belonging to a first part and a second surface belonging to a second part;
the first part projects outwardly from a side of the rocker arm; and
the rocker arm assembly is operative to move the first surface relative to the second surface in response to actuation of the cam follower.

2. The valvetrain of claim 1 , wherein the first surface is a peripheral surface of the first part, the peripheral surface extending along a direction in which the first part projects from the rocker arm.

3. The valvetrain of claim 1 , wherein:
the rocker arm assembly has a pivot axis; and
the electrical connection is made proximate the pivot axis.

4. The valvetrain of claim 1 , wherein:
the rocker arm assembly has a pivot axis; and
the first part is on the pivot axis.

5. The valvetrain of claim 1 , wherein:
the rocker arm assembly has a pivot axis; and
the first surface is substantially parallel to the pivot axis.

6. The valvetrain of claim 1 , wherein:
the rocker arm assembly has a pivot axis; and
either the first surface or the second surface has a radius of curvature;
a center of the radius of curvature substantially corresponds to the pivot axis.

7. The valvetrain of claim 1 , wherein the second part is a ribbon of metal that bends in relation to movement of the rocker arm.

8. The valvetrain of claim 7 , further comprising:
a lash adjuster that provides a fulcrum for the rocker arm assembly;
wherein the second part bends while remaining in contact with the first part as the lash adjuster extends and retracts when adjusting lash.

9. The valvetrain of claim 1 , further comprising:
a pivot axis on which the rocker arm assembly pivots;
a first distance defined between the pivot axis and a point on the rocker arm that is furthest away from the pivot axis; and
a second distance defined between the pivot axis and the first part;
wherein the second distance is less than or equal to 10% of the first distance.

10. The valvetrain of claim 9 , wherein
the second distance is less than or equal to 2% of the first distance.

11. A valvetrain for an internal combustion engine of a type that has a combustion chamber, a moveable valve having a seat formed in the combustion chamber, and a camshaft, the valvetrain comprising:
a rocker arm assembly comprising a rocker arm and a cam follower configured to engage a cam mounted on the camshaft as the camshaft rotates; and
an electrical circuit comprising an electrical device mounted to the rocker arm;
wherein the electrical circuit includes an electrical connection made by abutment between a first surface belonging to a first part and a second surface belonging to a second part;
the second part is a spring that bends in relation to movement of the rocker arm; and
the rocker arm assembly is operative to move the first surface relative to the second surface in response to actuation of the cam follower.

12. The valvetrain of claim 11 , wherein:
the rocker arm assembly has a pivot axis; and
the electrical connection is made proximate the pivot axis.

13. The valvetrain of claim 11 , wherein:
the rocker arm assembly has a pivot axis; and
the first surface is substantially parallel to the pivot axis.

14. The valvetrain of claim 11 , wherein:
the rocker arm assembly has a pivot axis; and
either the first surface or the second surface has a radius of curvature;
a center of the radius of curvature substantially corresponds to the pivot axis.

15. The valvetrain of claim 11 , wherein the spring is a ribbon of metal.

16. The valvetrain of claim 15 , further comprising:
a lash adjuster that provides a fulcrum for the rocker arm assembly;
wherein the second part bends while remaining in contact with the first part as the lash adjuster extends and retracts when adjusting lash.

17. The valvetrain of claim 11 , further comprising:
a pivot axis on which the rocker arm assembly pivots;
a first distance defined between the pivot axis and a point on the rocker arm that is furthest away from the pivot axis; and
a second distance defined between the pivot axis and the first surface;
wherein the second distance is less than or equal to 10% of the first distance.

18. The valvetrain of claim 17 , wherein
the second distance is less than or equal to 2% of the first distance.

Assignees

• Eaton Intelligent Power Ltd

Inventors

• Liskar Petr
• Cecrle Jiri
• Stretch Dale Arden
• Campbell Michael J
• Drabek Tomas
• Mccarthy Jr James Edward
• Zurface Austin Robert
• Benjey Robert Philip
• Yankovic Eric John
• Vandeusen Brian Karl
• Gillette Nicholas Peter
• Stanton Michael James
• Tembreull Thomas Michael
• Spoor Anthony Leon

Classifications

• F01L13/0005 Primary

  Deactivating valves · CPC title

• F01L2001/0535

  Single overhead camshafts [SOHC] · CPC title

• F01L1/2405

  by means of a hydraulic adjusting device located between the cylinder head and rocker arm · CPC title

• F01L2201/00

  Electronic control systems; Apparatus or methods therefor · CPC title

• F01L1/185

  Overhead end-pivot rocking arms · CPC title