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. 31, 2005
Filed:
Dec. 09, 2002
Akira Tsubouchi, Maebahshi, JP;
Kiyoshi Okubo, Maebahshi, JP;
Yasushi Watanabe, Maebahshi, JP;
NSK Ltd., Tokyo, JP;
Abstract
A hollow rack shaft is manufactured through a first step, a second step and a third step. At the first step, the plate-like workpiece of substantial rectangular shape is press-formed into a gutter-like shape. At the second step, a row of rack teeth is press-formed by a preliminary forming step and a main forming step on the flat bottom portion of the workpiece formed in the first step. The die set used at the second step is provided with a recess for releasing surplus workpiece material within the die clearance at a stroke end of the pressworking and each die set is divided into a plurality of segments at the recess. At the third step, each of a pair of legs of the workpiece is bent in a semi-circular shape so as to be butted to each other.