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:
Jul. 16, 2019
Filed:
Jul. 09, 2015
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Kenji Tamura, Takatsuki, JP;
Junichi Okubo, Amagasaki, JP;
Koichiro Ishihara, Kyoto, JP;
Ken Yoshino, Guangdong, CN;
Kunihiro Yabuno, Matsubara, JP;
Hiroyuki Kurokawa, Nishinomiya, JP;
Tomohisa Yamashita, Suita, JP;
Sho Takamoto, Osaka, JP;
NIPPON STEEL & SUMITOMO METAL CORPORATION, Tokyo, JP;
Abstract
A method for producing a forged crankshaft includes: a preforming step of forming a preformed blank with no flash, the preformed blank including a shape of the crankshaft, wherein the crank arm have excess projecting portions at an outer peripheries of side portions of the crank arm near the crank pin; a die forging step of forming a forged blank with flash by pressing the preformed blank with a pair of first dies; and a trimming step of removing the flash from the forged blank. In the die forging step, while a second die is abutted against a journal-side surface of the crank arm and holds the surface, the excess projecting portions of the crank arm are deformed by the first dies so as to increase the side portions of the crank arm in thickness.