US 12,274,201 B2
String trimmer
Hugh A. Dales, Germantown, WI (US); and Mitchell E. Carpenter, Milwaukee, WI (US)
Assigned to Milwaukee Electric Tool Corporation, Brookfield, WI (US)
Filed by MILWAUKEE ELECTRIC TOOL CORPORATION, Brookfield, WI (US)
Filed on Jun. 18, 2021, as Appl. No. 17/351,588.
Claims priority of provisional application 63/041,625, filed on Jun. 19, 2020.
Prior Publication US 2021/0392812 A1, Dec. 23, 2021
Int. Cl. A01D 34/58 (2006.01); A01D 34/00 (2006.01); A01D 34/416 (2006.01); A01D 34/90 (2006.01); H02K 9/06 (2006.01); H02K 11/21 (2016.01); H02K 11/33 (2016.01)
CPC A01D 34/58 (2013.01) [A01D 34/006 (2013.01); A01D 34/416 (2013.01); A01D 34/90 (2013.01); H02K 9/06 (2013.01); H02K 11/21 (2016.01); H02K 11/33 (2016.01); H02K 2203/03 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A string trimmer comprising:
a handle unit including a handle unit housing that defines a grip portion and a battery receptacle;
a head unit including a head unit housing, an electric motor, and a rotatable trimmer head;
a shaft assembly coupling the handle unit to the head unit; and
a circuit board assembly supported within the head unit housing, the circuit board assembly including a heat sink and a circuit board that comprises a controller configured to control the electric motor,
wherein the electric motor includes a rotor assembly and a stator assembly surrounding the rotor assembly,
wherein the circuit board comprises a first circuit board located between the stator assembly and the heat sink, and
wherein the circuit board assembly further includes a second circuit board located between the first circuit board and the stator assembly.