US 12,142,971 B2
Electric powered work machine
Akihiro Nakamoto, Anjo (JP)
Assigned to MAKITA CORPORATION, Anjo (JP)
Appl. No. 17/624,775
Filed by MAKITA CORPORATION, Anjo (JP)
PCT Filed Jun. 17, 2020, PCT No. PCT/JP2020/023846
§ 371(c)(1), (2) Date Jan. 4, 2022,
PCT Pub. No. WO2021/005990, PCT Pub. Date Jan. 14, 2021.
Claims priority of application No. 2019-129233 (JP), filed on Jul. 11, 2019.
Prior Publication US 2022/0247279 A1, Aug. 4, 2022
Int. Cl. H02K 11/28 (2016.01); B25D 16/00 (2006.01); H02K 7/14 (2006.01)
CPC H02K 11/28 (2016.01) [H02K 7/145 (2013.01); B25D 16/006 (2013.01); B25D 2216/0084 (2013.01); B25D 2250/095 (2013.01); B25D 2250/265 (2013.01); H02K 2211/03 (2013.01)] 11 Claims
OG exemplary drawing
 
1. An electric powered work machine, comprising:
a motor;
a manually-operated switch configured to be turned ON/OFF by a user of the electric powered work machine to drive/stop the motor;
a grip configured to be gripped by a hand of the user;
a current-carrying path to the motor;
a switching circuit including a first semiconductor device, the first semiconductor device being provided on the current-carrying path and configured to control a conducted state of the motor;
a circuit board including the switching circuit and a portion of the current-carrying path;
a metal case fixed to the circuit board; and
a heat radiation sheet abutting on the circuit board and the metal case;
the circuit board including:
a first surface including the switching circuit,
a second surface abutting on the heat radiation sheet,
a board conductive line including a conductive material, and
a circuit arrangement area including the switching circuit and two or more first through holes, the two or more first through holes penetrating from the first surface to the second surface,
the board conductive line including at least the portion of the current-carrying path and electrically connected to the switching circuit,
the board conductive line including:
a first conductive line portion arranged on the first surface,
a second conductive line portion arranged on the second surface, and
two or more third conductive line portions arranged on respective inner surfaces of the first through holes,
the first conductive line portion being electrically connected to the second conductive line portion via the two or more third conductive line portions.