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:
Dec. 29, 1987
Filed:
Sep. 25, 1986
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Harmonic Drive Systems Inc., Tokyo, JP;
Abstract
This invention relates to reduction in frictional torque of a harmonic drive type transmission apparatus having a circular spline, a flexspline, and a wave generator. A wave generator bearing of the wave generator has a retainer for holding a number of balls which roll between the inner and outer races to be in contact with an inner race and an outer race and to be separated from each other in the circumferential direction. The ball retainer has a number of radial pockets for storing the balls. Each pocket is formed into a shape forming a narrow (in the circumferential direction) opening portion at the inner race side and a wide (in the circumferential direction) opening portion at the outer race side. The balls are in contact with the opening portion at the inner race side in the pockets at the minor axis positions of a drive cam, and the balls are in contact with substantially the central portion of the pocket inner surface at the major axis positions of the cam.