To prevent an electrical connection failure or a mechanical contact failure between a brush and a commutator from being caused by loosening of fastening of a screw part of a cap for pressing a carbon brush inserted into a brush holder due to vibration, in a power tool using a commutator motor.
In this power tool, a structure in which the carbon brush 53 is inserted into the brush holder 9 and the cap 97 is screwed and fastened to the brush holder 9 via a coil spring 93 is provided, and a cap cover member 23 of a tail cover 2 is pressed on the cap 97 of the brush holder 9. The cap cover member 23 or the cap 97 is provided with a projection machining part 24 in a contacting part with the cap cover member 23 and the cap 97. By the projection machining part 24, constraint force is imparted to prevent loosening of the cap 97 screwed to the brush holder 9 due to vibration generated in a motor mechanism part or a power transmission mechanism part.
TACHIBANA TOSHIHIKO
SATO YUICHI
TERANISHI TAKUYA
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