BRUSH

摘要

PROBLEM TO BE SOLVED: To obtain a brush which realizes excellent rectifying operation even if the brush is inclined by solving control of voltage drop and reduction of friction force. SOLUTION: This brush is placed in contact with a commutator (4) to feed a motor (2) with power and is accommodated within a brush holder (3). This brush is moreover made of copper particles (11) having the grain size of 5 to 30μm or less by 70 wt.% or more and graphite particles (12) having the grain size of 30μm or less and is shaped to gradually become wider toward both end portions in the rotating direction of the commutator from the center area at the place in contact with the commutator.