Manufacturing method for coil spring
US8607605B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 11, 2011 |
| Grant date | Dec 17, 2013 |
| Priority date | — |
| Expiry date | Nov 11, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/479
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A spring wire is subjected to a first shot peening process and a second shot peening process. In the first shot peening process, a first shot is projected on the spring wire at a first projectile speed. High kinetic energy of the first shot produces compressive residual stress in a region ranging from the surface of the spring wire to a deep position. In the second spring wire process, a second shot is projected at a second projectile speed lower than the speed of the first shot. The kinetic energy of the second shot is lower than that of the first shot. The low kinetic energy of the second shot increases the compressive residual stress in a region near the surface of the spring wire.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.