Patent ID: 8847447

Claim:
A motor assembly comprising: an output shaft which is supported by a case to be rotatable around a rotation-axis; a rotor which is integrally coupled with the output shaft; a stator which is fixed to the case; a resolver which detects a rotation angle of the rotor, wherein the resolver includes: an output-side rotation member that has an annular shape and is integrally coupled with the output shaft; a resolver rotor that is coupled with the output-side rotation member and is disposed coaxially with the rotation-axis, wherein a fitting hole is formed in the resolver rotor and is disposed coaxially with the rotation-axis; and a resolver stator that is fixed to the case coaxially with the rotation-axis to detect an angle between the resolver rotor and the resolver stator; a protruding portion that protrudes from an end face of the output-side rotation member, wherein the protruding portion is fitted into the fitting hole; a protrusion which is provided at the resolver rotor to protrude from the fitting hole inward in a radial direction; a groove which is provided concavely at the protruding portion to receive the protrusion inserted in a rotation-axis direction; and a restriction portion which restricts relative rotation between the resolver rotor and the output-side rotation member, wherein the restriction portion is formed at a position of end face of the output-side rotation member, which is closer to the rotation-axis than the protrusion, by swaging so that gaps between the protrusion and the groove are filled.