The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 17, 2013
Filed:
Nov. 11, 2011
Akira Tange, Yokohama, JP;
Hideki Okada, Yokohama, JP;
Motoi Uesugi, Yokohama, JP;
Yosuke Hisano, Yokohama, JP;
Akira Tange, Yokohama, JP;
Hideki Okada, Yokohama, JP;
Motoi Uesugi, Yokohama, JP;
Yosuke Hisano, Yokohama, JP;
NHK Spring Co., Ltd., Tokyo, JP;
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.