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:
Apr. 10, 2018
Filed:
Jan. 15, 2015
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Tomihiko Fukuyasu, Tokyo, JP;
Nobutaka Tanimoto, Fostoria, OH (US);
Junichi Okubo, Amagasaki, JP;
Kunihiro Yoshida, Nishinomiya, JP;
NIPPON STEEL & SUMITOMO METAL CORPORATION, Tokyo, JP;
Abstract
A method of manufacturing a die forged crankshaft to be mounted in a two or more cylinder reciprocating apparatus includes: an upsetting step that includes upsetting a billet having a constant cross-sectional area along an entire length thereof to form a blank having an enlarged cross-sectional area at a region between a portion to be formed into a leading crank arm of the crankshaft and a portion to be formed into a trailing crank arm thereof; a die forging step that includes die forging the blank formed in the upsetting step to form a forged blank having a shape of the crankshaft with a flash; and a trimming step that includes trimming the flash from the forged blank formed in the die forging step. This makes it possible to improve the material utilization and to use a billet having a cross-sectional size as small as possible.