US 12,308,701 B2
Motor
Naoto Toyomura, Kitasaku-gun (JP); and Takuji Yamada, Kitasaku-gun (JP)
Assigned to MINEBEA MITSUMI Inc., Nagano (JP)
Filed by MINEBEA MITSUMI Inc., Nagano (JP)
Filed on May 5, 2022, as Appl. No. 17/662,096.
Claims priority of application No. 2021-081210 (JP), filed on May 12, 2021.
Prior Publication US 2022/0368178 A1, Nov. 17, 2022
Int. Cl. H02K 1/17 (2006.01); H02K 3/28 (2006.01)
CPC H02K 1/17 (2013.01) [H02K 3/28 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A motor comprising:
a stator including a plurality of magnetic bodies disposed side by side in a circumferential direction and a coil wound around each of the plurality of magnetic bodies and an insulator;
a rotor including a thickness equal to or greater than a thickness of the magnetic body in a rotational axis direction;
a sensor disposed to oppose the rotor in the rotational axis direction;
a substrate opposing the stator in a rotational axis direction, and
a housing including the sensor, wherein
the coil includes a first layer and a second layer stacked on the first layer;
the rotor is disposed inside the stator,
the housing accommodates the rotor and the stator and the substrate,
1≤D/L holds, where L is a thickness of the magnetic body in the rotational axis direction and D is a width of the magnetic body in a radial direction;
the second layer is a layer outermost from the magnetic body in the rotational axis direction and in the circumferential direction;
in the radial direction, a conducting wire of the first layer and a conducting wire of the second layer making up an inner edge of the coil are in contact with each other;
in the radial direction, a conducting wire of the first layer and a conducting wire of the second layer making up an outer edge of the coil are in contact with each other,
the sensor is located at a side of the rotor relative to the substrate in the rotational axis direction, and
the thickness of the magnetic body in the rotational axis direction is greater than a thickness of the coil and the insulator in the rotational axis direction,
wherein a ratio of a length from an inner edge to an outer edge of the second layer with respect to a length from an inner periphery part to an outer periphery part of the substrate in the radial direction is within a range of 50% to 90%.