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:
May. 07, 2002
Filed:
Nov. 18, 1999
Tatsuro Ochi, Muroran, JP;
Hideo Kanisawa, Muroran, JP;
Kenichiro Naito, Muroran, JP;
Joji Tamura, Muroran, JP;
Masayoshi Saga, Mooka, JP;
Other;
Abstract
Disclosed are a high strength drive shaft and a process for producing the same. The high strength drive shaft comprises as a steel material, by weight, carbon: 0.48 to 0.58%, silicon: 0.01 to 0.15%, manganese: 0.35 to 0.75%, sulfur: 0.005 to 0.15%, molybdenum: 0.1 to 0.35%, boron 0.0005 to 0.005%, aluminum: 0.015 to 0.05%, and titanium: 0.02 to 0.08%, the proportion of the effective case depth of an involute serration in its end of the drive shaft being 0.3 to 0.7 in terms of the ratio of the effective case depth t to the radius r, t/r. The involute serration in its end preferably has a former austenite grain size of not less than 8 in terms of the grain size number specified in JIS (Japanese Industrial Standards). A steel comprising the above constituents and having a hardness of 85 to 95 HRB is machined and form rolled into a shaft, and the shaft is induction hardened and then tempered at 120 to 200° C. to produce the high strength drive shaft.