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:
Mar. 17, 1992
Filed:
Oct. 05, 1990
Yasushi Ishikawa, Sagamihara, JP;
Mikio Yamanaka, Sagamihara, JP;
Yutaka Sadano, Sagamihara, JP;
Shingo Tanioka, Tokai, JP;
Tetsuro Inomata, Tokai, JP;
Toshikazu Nakagawa, Tokai, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
A method of diametrically contracting a cylindrical body, includes the steps of grasping the cylindrical body with a plurality of elongated grasping members, preparing a cylindrical drawing die having an opening at one end and a tapered inside peripheral surface, drawing the grasping members together with the cylindrical body into the drawing die, through the opening, and applying a compression force to the cylindrical body through the grasping members due to the passage along through the tapered inside peripheral surface, to thereby cause the cylindrical body to be diametrically contracted. During the drawing process, since the cylindrical body does not come into direct contact with the drawing die, neither scratches nor baking cracks are produced on the outside surface of the cylindrical body.