Motor-driven tool
AssigneeHitachi Koki Co., Ltd.
InventorsKatsuhiro Oomori, Chikai Yoshimizu, Masanori Watanabe, Shinki Ohtsu, Takuma Saito, Toshiyuki Nemoto
Life of this patent
Estimating the term…
Abstract
In a motor-driven tool, a carbon brush part 8 is arranged between a suction port 6 and a commutator 11 of the motor and includes a cylindrical side wall 8a. The cylindrical side wall 8a located on an outer periphery of the commutator 11 is provided with a tapered portion 8b which grows wider toward the commutator 11 and grows narrower toward a coil end 10 of the armature. Between the carbon brush part 8 and the coil end 10, there is provided a heat radiating plate 4 made of metal and adapted to be engaged with the carbon brush part 8.
Claims16
A motor-driven tool comprising:
- a motor including an armature and a stator;
- a cooling fan provided on a rotary shaft of said motor;
- a carbon brush part adapted to be cooled by said cooling fan;
- and
- a housing for containing said carbon brush part and said motor, said housing being provided with a suction port arid a discharge port;
- wherein said carbon brush part includes a cylindrical side wall between said suction port and a commutator of said motor, said cylindrical side wall located close to an outer periphery of said commutator being provided with a tapered portion which extends along a majority of the inner face of said cylindrical side wall and which grows wider toward said commutator and grows narrower toward a coil end of said armature, and wherein a heat radiating plate made of metal engages said carbon brush part and is provided between said carbon brush part and said coil end.
A motor-driven tool comprising:
- a motor including an armature and a stator;
- a fan provided on a shaft of said motor;
- a housing containing said motor, wherein said housing comprises a suction port and a discharge port;
- and
- a carbon brush block contained by said housing and comprising a cylindrical side wall between said suction port and a commutator of said motor, wherein a majority of an inner face of said cylindrical side wall tapers from a wide end toward said commutator and to a narrow end toward a coil end of said armature.
A motor-driven tool comprising:
- a motor including an armature and a stator;
- a fan provided on a shaft of said motor;
- a housing containing said motor, wherein said housing comprises a suction port and a discharge port;
- a carbon brush block contained in said housing;
- and
- a metal heat radiating plate engaging said carbon brush part and having a shape that follows a contour of a coil end of said armature.
Dependencies are inferred from the claim text.