Coreless motor

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.

1 . A coreless motor which comprises:
 a fixed shaft extending in the axial direction at the center of said coreless motor and being passed through said coreless motor;   a cylindrical coil disposed concentrically with respect to said fixed shaft and having an end surface on one side that is supported by a stator and extending in the direction in which said fixed shaft extends;   a rotor disposed concentrically with respect to said fixed 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 the 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 fixed shaft disposed at radial center;   a cylindrical housing that includes a cylindrical part disposed concentrically with respect to said fixed shaft in the outside of said cylindrical outer yoke in the radial direction, said cylindrical part rotating about said fixed shaft; and   a rotational motion transmission mechanism disposed in the interior of said cylindrical housing and being operated to transmit the rotational motion of said rotor about said fixed shaft to said cylindrical housing.   
     
     
         2 . The coreless motor as defined in  claim 1 , wherein said rotational motion transmission mechanism comprises a gear mechanism that includes a plurality of gear members, said gear members included in said gear mechanism being rotatably supported by said fixed shaft passing through said gear member located on the side of said fixed shaft in the axial direction.