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. 25, 2000
Filed:
Jun. 25, 1998
Keizo Kobayashi, Anjo, JP;
Kazunori Ishikawa, Anjo, JP;
Kazuhisa Ozaki, Anjo, JP;
Toshihiro Tomino, Anjo, JP;
Mikio Iwase, Anjo, JP;
Hiroshi Kato, Anjo, JP;
Tatsuo Tozuka, Anjo, JP;
Atsushi Tabata, Toyota, JP;
Kagenori Fukumura, Toyota, JP;
Yasuo Hojo, Toyota, JP;
Shoichi Sayo, Toyota, JP;
Hideki Miyata, Toyota, JP;
Aisin AW Co., Ltd., Anjo, JP;
Toyota Jidosha Kabushiki Kaisha, Aichi-ken, JP;
Abstract
A gear having high pitching resistance, sufficient surface hardness, sufficient hardened depth, high abrasion resistance, high breakage resistance, high fatigue resistance, and low gear noises. A material equivalent to JIS-SCM420 is soft nitrided for two hours in a mixture gas containing 45 to 65 volume % of residual NH.sub.3 at a gas temperature of 530 to 565.degree. C., thus producing a compound layer having a hardness equal to or higher than that of the material plus Hv 50 and a thickness of 200 .mu.m or more.