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:
Jan. 02, 2007
Filed:
Nov. 27, 2001
Tadayuki Tsutsui, Matsudo, JP;
Kei Ishii, Higashi Katsushika-gun, JP;
Yoshihiro Tanimura, Chiryu, JP;
Kouji Yamada, Okazaki, JP;
Yuuichi Aoki, Chita-gun, JP;
Tadayuki Tsutsui, Matsudo, JP;
Kei Ishii, Higashi Katsushika-gun, JP;
Yoshihiro Tanimura, Chiryu, JP;
Kouji Yamada, Okazaki, JP;
Yuuichi Aoki, Chita-gun, JP;
Hitachi Powdered Metals Co., Ltd., Matsudo, JP;
Denso Corporation, Kariya, JP;
Abstract
An inexpensive mechanical fuse having a high fatigue limit ratio and high rupture reliability, and superior in forming performance, and a method of manufacturing the same are presented. The mechanical fuse is composed of Fe-based sintered alloy, and comprises an inner rimfixed to one power transmission shaft, an outer rimfixed to the other power transmission shaft, and plural armsfor linking the inner rimand outer rim, which are formed integrally. The armsinclude rupture portionswhich are ruptured when exposed to an overload torque. By treating in steam, an iron oxide phase is formed in the surface layer and pore inner wall. The iron oxide phase is effective to form round pores and lower the notch sensitivity. As a result, the fatigue strength and fatigue limit ratio are enhanced.