Patent ID: 8169111

Claim:
A brushless motor comprising: a stator comprising an insulator; a rotor rotatably disposed in an inner circumferential portion of the stator; and a resolver configured to detect a rotational position of the rotor with respect to the stator, wherein the resolver comprises: a resolver stator disposed at a fixed circumferential position with respect to the stator, and a resolver rotor disposed at a fixed circumferential position with respect to the rotor, wherein the resolver stator comprises a first engagement portion comprising a plurality of concave engagement portions disposed at equal distances from a center of the resolver stator, wherein the stator comprises a second engagement portion comprising a plurality of projection engagement portions disposed on the insulator at equal distances from a center of the insulator, wherein the plurality of projection engagement portions are fitted into the plurality of concave engagement portions, wherein a rotor magnet is positioned and fixed in a circumferential direction via a magnet holder at a position facing the stator in an outer circumference of a rotating shaft, and wherein the resolver rotor is positioned and fixed in a circumferential direction with respect to the rotor via the magnet holder.