Cam actuated roller assembly and clad roller pin for same

• US 20090038572A1
• Filed: 08/09/2007
• Published: 02/12/2009
• Est. Priority Date: 08/09/2007
• Status: Abandoned Application

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Lindell, Arthur S., Langewisch, Edwin H.
• Application Number:
  US11/891,177
• Publication Number:
  US 20090038572A1
• Time in Patent Office: Days
• US Class Current: 123/90.440
• CPC Class Codes: F01L 1/146 Push-rods
• CPC Class Codes: F01L 1/18 Rocking arms or levers
• CPC Class Codes: F01L 1/181 Centre pivot rocking arms
• CPC Class Codes: F01L 2301/00 Using particular materials
• CPC Class Codes: F01L 2305/00 Valve arrangements comprising rollers
• CPC Class Codes: F01L 2305/02 Mounting of rollers
• CPC Class Codes: Y10T 29/49295 Push rod or rocker arm making
• CPC Class Codes: Y10T 74/2101 Cams

Abstract

Cam actuated systems, such as valve trains for an engine, typically bring cam lobe action to the engine valve via a linkage that includes a cam actuated roller assembly which may be either a rocker or a lifter. These cam actuated rocker assemblies include a housing with a pair of arms with roller support bores there through. A roller support pin is received in the roller support bores, and rotationally supports a roller mounted about the roller pin and between the arms of the housing. The roller pin may include a relatively hard and inexpensive core, such as steel, cladded with a relatively soft more expensive metal, such as bronze.

Claims

1. A cam actuated roller assembly comprising:

a housing defining a shaft bore and including a pair of spaced arms that each define a roller support bore;

a roller pin extending between the arms and received in each of the roller support bores;

a roller mounted for rotation about the roller pin and positioned between the arms; and

the roller pin having a core of a first metallic material surrounded by a cladding of a second metallic material that is different from the first metallic material.

2. The cam actuated roller assembly of claim 1 wherein the core has a conical outer surface received in a conically shaped bore defined by the cladding.

3. The cam actuated roller assembly of claim 2 wherein the first metallic material includes steel;

and

the second metallic material includes bronze.

4. The cam actuated roller assembly of claim 3 wherein the roller pin consists of a steel core with bronze cladding.

5. The cam actuated roller assembly of claim 1 wherein the first metallic material includes steel;

and

the second metallic material includes bronze.

6. The cam actuated roller assembly of claim 5 wherein the roller pin consists of a steel core with bronze cladding.

7. The cam actuated roller assembly of claim 1 wherein the housing is a rocker.

8. The cam actuated roller assembly of claim 1 wherein the housing is a lifter.

9. The cam actuated roller assembly of claim 1 wherein the cladding has a thickness of about two millimeters.

10. The cam actuated roller assembly of claim 5 wherein the roller pin consists of a steel core with bronze cladding.

11. A roller pin comprising:

a core of a first metallic material surrounded by a cladding of a second metallic material that is different from the first metallic material;

the first metallic material includes steel; and

the second metallic material includes bronze.

12. The roller pin of claim 11 consisting of a steel core with bronze cladding.

13. The roller pin of claim 12 wherein the core has a conical shape received in a conically shaped bore of the cladding.

14. The roller pin of claim 11 wherein the core has a conical shape received in a conically shaped bore of the cladding.

15. A method of making a cam actuated roller assembly, comprising the steps of:

forming a roller pin by cladding a relatively hard metallic core with a relatively soft metal;

positioning a roller around the roller pin and between a pair of arms of a housing; and

press fitting the roller pin in a pair of roller support bores through the arms of the housing.

16. The method of claim 15 wherein the forming step includes cladding a steel core with bronze.

17. The method of claim 15 including a step of forming the housing into a rocker.

18. The method of claim 15 including a step of forming the housing as a lifter.

19. The method of claim 15 wherein the forming step includes cladding a relatively large radius steel core with a thin radial layer of bronze.

20. The method of claim 19 including a step of machining surface features on an outer surface of the roller pin after the cladding step.