IP Library Granted Patent US 12689262
Granted Patent B2
US 12689262 · App. 18/484,902 · Granted Jul 21, 2026

Coreless motor

Inventor: Manabu Shiraki (Yamato, JP)
Assignee: CORELESS MOTOR CO., LTD.
H02K7/116H02K3/47H02K16/02
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Quick Facts
Patent No.
US 12689262
App. No.
18/484,902
Granted
Jul 21, 2026
Kind
B2
Abstract

A coreless motor includes a shaft that extends in the axial direction at the center of the coreless motor and passes through said coreless motor; a coil is disposed with respect to the shaft, and has an end surface on one side that is supported by a stator and extends in the direction in which the shaft extends; a rotor that is disposed with respect to the fixed shaft and includes a cylindrical inner yoke and an outer yoke positioned so that the coil is sandwiched between the yokes, the yokes being provided with a magnet positioned on the side of the yoke, a magnet circuit being formed between the yokes, and the rotor being supported by the shaft at the radial center; a housing that includes a cylindrical part disposed concentrically with respect to the fixed shaft on the outside of the outer yoke in the radial direction.

Claims (8)

1 . A coreless motor which comprises:

a shaft extending in an axial direction of said motor and being passed through said motor;

a cylindrical coil disposed stationarily and concentrically with respect to said shaft and having an end surface on one side that is supported by a stator and extending in the direction in which said shaft extends;

a rotor disposed concentrically with respect to said shaft and comprising a cylindrical inner yoke and a cylindrical outer yoke positioned so that said cylindrical coil is sandwiched between said cylindrical inner yoke and said cylindrical outer yoke in a radial direction, either said cylindrical inner yoke or said cylindrical outer yoke has a magnet positioned on the side of said cylindrical inner yoke that faces said cylindrical outer yoke or said cylindrical outer yoke that faces said cylindrical inner yoke, a magnet circuit being formed between said cylindrical inner yoke and said cylindrical outer yoke, and said rotor being rotatably supported by said shaft disposed at a radial center;

a cylindrical housing having a cylindrical part located outside said outer yoke in the radial direction and disposed concentrically with respect to said shaft, said cylindrical part can rotate about said shaft; and

a rotational motion transmission mechanism located within said cylindrical housing and mounted within said cylindrical coil in the radial direction of said cylindrical coil and being operated to transmit the rotational motion of said rotor about said shaft to said cylindrical housing thereby transmit the rotational motion of said rotor about said shaft to any external devices outside the coreless motor;

said rotational motion transmission mechanism comprises a gear mechanism that includes a plurality of gear members mounted within said cylindrical coil in the radial direction of said cylindrical coil, the plurality of gear members including a high-speed side sun gear, and the high-speed side sun gear being rotatably supported by said shaft which passes through said high-speed side sun gear;

and said shaft extending in an axial direction of said cylindrical housing and rotatably supporting said cylindrical housing.