Piston pin and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-12241549-B2
Application number	US-202117244646-A
Country	US
Kind code	B2
Filing date	Apr 29, 2021
Priority date	Feb 8, 2021
Publication date	Mar 4, 2025
Grant date	Mar 4, 2025

Abstract

A piston pin includes a pipe-shaped main body made of an iron-based sintered alloy. The piston pin is installed to penetrate an upper end of the connecting rod and the piston and the piston pin has an eccentric mass center in a circumferential direction.

First claim

What is claimed is:

1. A piston pin comprising:
a pipe-shaped main body made of an iron-based sintered alloy,
wherein the piston pin is configured to be installed to penetrate an upper end of a connecting rod and a piston,
wherein a mass center of the piston pin is eccentric in a circumferential direction,
wherein the piston pin includes a first area and a second area divided in the circumstantial direction, and
wherein the first area and the second area have different densities.

2. The piston pin of claim 1 , wherein
the iron-based sintered alloy includes, with respect to an entire weight thereof:
carbon (C) at 0.4 wt % to 0.8 wt %;
chromium (Cr) at 0.2 wt % to 3.5 wt %;
molybdenum (Mo) at 0.1 wt % to 0.3 wt %;
nickel (Ni), manganese (Mn), copper (Cu), or a mixture thereof at 0.2 wt % to 2.0 wt %; and
iron (Fe) as a balance.

3. The piston pin of claim 1 , wherein
a density difference between the first area and the second area is 0.05 g/cm 3 or more.

4. The piston pin of claim 1 , wherein
the first area occupies an area of 30 degrees to 330 degrees in the circumferential direction.

5. The piston pin of claim 1 , wherein
an area dividing line separating the first area from the second area forms an angle of 90 degrees with a tangent of an outer diameter of the pipe-shaped main body or a tangent of an inner diameter of the pipe-shaped main body.

6. The piston pin of claim 1 , wherein
a center of an outer diameter of the pipe-shaped main body and a center of an inner diameter of the pipe-shaped main body are eccentric by 0.1 mm or more.

7. A piston pin comprising:
a pipe-shaped main body made of an iron-based sintered alloy,
wherein the piston pin is configured to be installed to penetrate an upper end of a connecting rod and a piston,
wherein a mass center of the piston pin is eccentric in a circumferential direction,
wherein the piston pin includes a first area and a second area divided in the circumferential direction, and
wherein the first area includes a metal infiltrating material.

8. The piston pin of claim 7 , wherein
the metal infiltrating material contains copper (Cu).

9. The piston pin of claim 7 , wherein
a density difference between the first area and the second area is 0.05 g/cm 3 or more.

10. The piston pin of claim 7 , wherein
the iron-based sintered alloy includes, with respect to an attire weight thereof:
carbon (C) at 0.4 wt % to 0.8 wt %;
chromium (Cr) at 0.2 wt % to 3.5 wt %;
molybdenum (Mo) at 0.1 wt % to 0.3 wt %;
nickel (Ni), manganese (Mn), copper (Cu), or a mixture thereof at 0.2 wt % to 2.0 wt %; and
iron (Fe) as a balance.

11. A piston pin comprising:
a pipe-shaped main body made of an iron-based sintered alloy,
wherein the piston pin is configured to be installed to penetrate an upper end of a connecting rod and a piston,
wherein a mass center of the piston pin is eccentric in a circumferential direction,
wherein the piston pin includes a first area and a second area divided in the circumferential direction, and
wherein a metal paste is applied to an inner diameter surface of the first area.

12. The piston pin of claim 11 , wherein
the metal paste contains copper (Cu).

13. The piston pin of claim 11 , wherein
a density difference between the first area and the second area is 0.05 g/cm 3 or more.

14. The piston pin of claim 11 , wherein
the iron-based sintered alloy includes, with respect to an attire weight thereof:
carbon (C) at 0.4 wt % to 0.8 wt %;
chromium (Cr) at 0.2 wt % to 3.5 wt %;
molybdenum (Mo) at 0.1 wt % to 0.3 wt %;
nickel (Ni), manganese (Mn), copper (Cu), or a mixture thereof at 0.2 wt % to 2.0 wt %; and
iron (Fe) as a balance.

15. A piston pin comprising:
a pipe-shaped main body of an iron-based sintered alloy,
wherein the piston pin is configured to be installed to penetrate an upper end of a connecting rod and a piston,
wherein a mass center of the piston is eccentric in a circumferential direction,
wherein the piston pin includes a first area and a second area divided in the circumferential direction,
wherein the first area and the second area have different densities,
wherein a center of an outer diameter of the pipe-shaped main body and a center of an inner diameter of the pipe-shaped main body are eccentric by 0.1 mm or more, and
wherein the first area includes a metal infiltrating material, or a metal paste applied to an inner diameter surface of the first area.

16. The piston pin of claim 15 , wherein
the iron-based sintered alloy includes, with respect to an attire weight thereof:
carbon (C) at 0.4 wt % to 0.8 wt %;
chromium (Cr) at 0.2 wt % to 3.5 wt %;
molybdenum (Mo) at 0.1 wt % to 0.3 wt %;
nickel (Ni), manganese (Mn), copper (Cu), or a mixture thereof at 0.2 wt % to 2.0 wt %; and
iron (Fe) as a balance.

Assignees

• Hyundai Motor Co Ltd
• Kia Corp
• Sinteron

Inventors

• Kim Haksoo
• Kang Byung Chan
• Park Dong Wook
• Na Myeong Inn

Classifications

• B22F3/16

  in successive or repeated steps · CPC title

• B22F2301/15

  Nickel or cobalt · CPC title

• B22F2301/10

  Copper · CPC title

• B22F2301/35

  Iron · CPC title

• B22F2302/40

  Carbon, graphite · CPC title