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. 29, 2001
Filed:
Jun. 29, 1999
Wataru Takahashi, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A positioner includes a conductive rotary table on which a work-piece is placed, a conductive rotary shaft holding the rotary table, a conductive collector ring fixed concentrically with the rotary shaft, and a carbon brush contacting one face of the collector ring. The carbon brush has radial grooves formed on its contact face with the collector ring, and can be split into plural sections. Abrasive powder produced by friction between the brush and collector ring can be discharged through the grooves to outside of the brush, which eliminates sparks between these two elements, of which durability is thus substantially improved. Further, since the carbon brush is split into plural sections, it can be replaced with ease without dismounting the rotary shaft, which reduces maintenance problems.