US 12,456,897 B2
Power tool
Akira Naito, Anjo (JP)
Assigned to MAKITA CORPORATION, Anjo (JP)
Filed by MAKITA CORPORATION, Anjo (JP)
Filed on Sep. 21, 2022, as Appl. No. 17/949,687.
Claims priority of application No. 2021-187288 (JP), filed on Nov. 17, 2021.
Prior Publication US 2023/0150104 A1, May 18, 2023
Int. Cl. H02K 5/14 (2006.01); B25D 17/04 (2006.01); B25D 17/11 (2006.01); H02K 5/20 (2006.01); H02K 9/06 (2006.01); H02K 13/04 (2006.01); H02K 13/06 (2006.01); H02K 13/10 (2006.01)
CPC H02K 5/143 (2013.01) [B25D 17/04 (2013.01); H02K 5/148 (2013.01); H02K 5/207 (2021.01); H02K 9/06 (2013.01); H02K 13/04 (2013.01); H02K 13/06 (2013.01); H02K 13/10 (2013.01); B25D 17/11 (2013.01); B25D 2250/121 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A power tool, comprising:
a housing;
a stator fixed to the housing, the stator including a field coil;
an armature rotatable relative to the stator, the armature including a commutator;
two brushes configured to come in contact with the commutator; and
a brush holder unit holding the two brushes, the brush holder unit including
a stationary housing,
two contact rails held by the stationary housing and electrically connectable to the field coil, each of the contact rails including
a rail portion being arc-shaped, and
a terminal portion intersecting with the rail portion,
a movable housing holding the two brushes and movable relative to the stationary housing,
two first terminals held by the movable housing, each of the two first terminals being configured to come in contact with either of the two contact rails in response to movement of the movable housing,
two second terminals held by the movable housing, each of the two second terminals being electrically connectable to a corresponding brush of the two brushes, and
a choke coil located between at least one of the two first terminals and at least one of the two second terminals,
wherein
each of the two contact rails includes an arch to come in contact with the either of the two first terminals,
the stationary housing includes a rectangular portion, and
the terminal portion includes a distal end received in the rectangular portion.