Roller pin for cam actuated roller assembly

Patent metadata

Field	Value
Publication number	US-9546724-B2
Application number	US-201414153106-A
Country	US
Kind code	B2
Filing date	Jan 13, 2014
Priority date	Jan 13, 2014
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

The present disclosure provides a roller pin for a fuel pump. The roller pin includes a cylindrical body made of a first material extending between a first end and a second end. The roller pin includes an intermediate portion disposed between the first end and the second end of the cylindrical body. The intermediate portion is formed by depositing a second material on the cylindrical body. The roller pin further includes a longitudinal groove extending along the intermediate portion.

First claim

What is claimed is:

1. A roller pin for a fuel pump comprising:
a cylindrical body made of a first material extending between a first end and a second end, the first end and the second end having an outside diameter equal to a first diameter;
an intermediate portion disposed between the first end and the second end of the cylindrical body, the intermediate portion including a second material disposed continuously about a surface of the cylindrical body positioned from the first end to the second end, the intermediate portion having an outside diameter equal to the first diameter; and
a longitudinal groove extending along the intermediate portion;
wherein the first material has a greater strength characteristic than the second material and wherein the second material has a lower coefficient of friction than the first material.

2. The roller pin of claim 1 , wherein the longitudinal groove comprises a concave cavity having a first opening and a second opening.

3. The roller pin of claim 2 further comprising a first fluid passage and a second fluid passage at the first end and the second end of the cylindrical body, respectively.

4. The roller pin of claim 3 , wherein the first opening is fluidly connected to the first fluid passage via a third fluid passage.

5. The roller pin of claim 3 , wherein the second opening is fluidly connected to the second fluid passage via a fourth fluid passage.

6. The roller pin of claim 1 , wherein the first material is carburized heat-resistant steel.

7. The roller pin of claim 1 , wherein the second material is silica bronze.

8. A fuel pump comprising at least one cam actuated roller assembly, the cam actuated roller assembly comprising:
a cam follower defining a cavity;
a cam roller accommodated in the cavity, the cam roller defining a bore; and
a roller pin received in the bore and extending into the cavity, the roller pin rotatably supporting the cam roller, the roller pin comprising:
a cylindrical body made of a first material extending between a first end and a second end, the first end and the second end having an outside diameter equal to a first diameter;

an intermediate portion disposed between the first end and the second end of the cylindrical body, the intermediate portion including a second material disposed continuously about a surface of the cylindrical body positioned from the first end to the second end, the intermediate portion having an outside diameter equal to the first diameter; and
a longitudinal groove extending along the intermediate portion;
wherein the first material has a greater strength characteristic than the second material and wherein the second material has a lower coefficient of friction than the first material.

9. The fuel pump of claim 8 , wherein the longitudinal groove comprises a concave cavity having a first opening and a second opening.

10. The fuel pump of claim 9 , wherein the roller pin further comprising a first fluid passage and a second fluid passage at the first end and the second end respectively.

11. The fuel pump of claim 10 , wherein the first opening is fluidly connected to the first fluid passage via a third fluid passage.

12. The fuel pump of claim 10 , wherein the second opening is fluidly connected to the second fluid passage via a fourth fluid passage.

13. The fuel pump of claim 8 , wherein the first material is carburized heat-resistant steel.

14. The fuel pump of claim 8 , wherein the second material is silica bronze.

15. A method of manufacturing a roller pin for a fuel pump comprising:
removing a first material from an outer surface of a cylindrical body to define an annular undercut portion between a first end and a second end of the cylindrical body, the first end and the second end having an outside diameter equal to a first diameter;
depositing a layer of a second material continuously over the undercut portion by thermo-metal spraying to form an intermediate portion positioned from the first end to the second end, the intermediate portion having an outside diameter equal to the first diameter;
removing a portion of the layer of the second material from the intermediate portion to define a longitudinal groove; and
providing a concave cavity within the longitudinal groove;
wherein the first material has a greater strength characteristic than the second material and wherein the second material has a lower coefficient of friction than the first material.

16. The method of claim 15 further comprising providing a first opening and a second opening in the concave cavity.

17. The method of claim 15 further comprising providing a first fluid passage and a second fluid passage at the first end and the second end respectively.

18. The method of claim 17 further comprising fluidly connecting the first opening to the first fluid passage via a third fluid passage.

19. The method of claim 15 further comprising fluidly connecting the second opening to the second fluid passage via a fourth fluid passage.

20. The method of claim 15 wherein depositing a layer of a second material comprises applying a layer of silica bronze material over the undercut portion.

Assignees

• Caterpillar Inc

Inventors

• Unes John W
• Mack David C
• Hill Adam C

Classifications

• Y10T29/49293

  Camshaft making · CPC title

• F02M59/102 Primary

  Mechanical drive, e.g. tappets or cams (F02M45/063 takes precedence) · CPC title

• F16H53/06 Primary

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

• F02M63/0001

  Fuel-injection apparatus with specially arranged lubricating system, e.g. by fuel oil (lubrication of engines F01M) · CPC title

• F16H57/043

  within rotary parts, e.g. axial channels or radial openings in shafts · CPC title