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:
Mar. 31, 1992
Filed:
Sep. 05, 1989
Applicant:
Inventors:
Tadanori Tanaka, Yachiyo, JP;
Masao Nakamura, Shisui, JP;
Toshifumi Yamada, Shisui, JP;
Katuhyosi Takase, Tokyo, JP;
Kazuhiro Muramatsu, Kamagaya, JP;
Tosikazu Ebata, Funabashi, JP;
Assignee:
Horikiri Spring Mfg., Co., Ltd., Yachiyu, JP;
Primary Examiner:
Int. Cl.
CPC ...
C21D / ;
U.S. Cl.
CPC ...
148 124 ; 148 / ; 148908 ;
Abstract
A method of preparing a leaf spring having a heating step in which a raw material of a leaf spring is heated to austenite range temperature, a rolling step in which the above heated material is formed to a desirable shape, a working step in which the above rolling material is cut to a fixed length to form a chip hole, a bolt hole or the like, and a cooling step in which a camber is given to the above working material to cool to hardening in his state. Other five modified methods are also described.