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:
Nov. 25, 1997
Filed:
Mar. 18, 1996
Yasuyuki Fujiwara, Nishikamo-gun, JP;
Izuru Yamamoto, Toyota, JP;
Masazumi Onishi, Toyota, JP;
Toshiaki Tanaka, Nagoya, JP;
Yoshinari Tsuchiya, Kasugai, JP;
Atsushi Danno, Nagoya, JP;
Toyota Jidosha Kabushiki Kaisha, Aichi-ken, JP;
Abstract
A method for producing cast iron gears includes the steps of heating a blank composed of cast iron and having a teeth forming part to such a temperature that at least the teeth forming part is at least austenitized, and hot rolling the teeth forming part of the blank by pressing projecting teeth of a rolling machine against the teeth forming part which is in a hot state and within an austenitized range, while cooling the blank, thereby generating a teeth part in the teeth forming part of the blank. Hot rolling with a low plastic deformation resistance prevents lowering of strength due to the exposure of graphite particles of cast iron and occurrence of quenching cracks and rolling cracks, and improves gear accuracy.