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:
Sep. 01, 1992
Filed:
Mar. 14, 1991
Isao Shibuya, Matsudo, JP;
Mabuchi Motor Co., Ltd., Chiba, JP;
Abstract
A carbon brush for miniature motors comprising a stator using a permanent magnet as the field, and a rotor on which a rotor winding is wound, and having a commutator for feeding current to the rotor winding and brushes, formed by bonding graphite powder, for making sliding contact with the commutator; the brush being a metal-plated graphite brush formed by adding 0.1 wt. % to 12.0 wt. % of a fibrous material of particle sizes less than 40 microns and lengths less than 50 microns to metal-plated graphite powder formed by coating graphite powder with a metallic layer, and pressure-forming and sintering a mixture of the metal-plated graphite powder and the fibrous material; the graphite powder containing less than 0.05 wt. % of ashes, and the method of making the same.