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:
Oct. 02, 1990
Filed:
May. 30, 1989
Eiichi Katayama, Osaka, JP;
Kouichi Ueda, Osaka, JP;
Hiroaki Takebayashi, Osaka, JP;
Kazuo Rokkaku, Osaka, JP;
Koyo Seiko Co., Ltd., Osaka, JP;
Showa Tool Co., Ltd., Osaka, JP;
Abstract
A traction drive spindle device includes an input shaft connectable to a drive main shaft for rotation therewith. A hollow holder shaft is connected to an output end of the input shaft in coaxial relation thereto, the hollow holder shaft having a plurality of planetary rollers mounted thereon intermediate opposite ends of the holder shaft. A high-speed spindle is rotatably received in a bore of the hollow holder shaft, the high-speed spindle having an inner end portion which is received in the bore and serves as a sun shaft disposed in rolling contact with the planetary rollers. A housing is mounted on the outer periphery of the holder shaft through a first ball-and-roller bearing so as to be rotatable relative to the holder shaft, the housing having a fixed ring fixed to an inner periphery thereof. The planetary rollers are disposed in rolling contact with the fixed ring. A second ball-and-roller bearing is interposed between the holder shaft and the high-speed spindle. Only the balls and both the balls and the rollers of the second ball-and-roller bearing are made of ceramics.