Patent ID: 9601953
Date: 2017-03-21
CPC Classifications: H02K

Claim:
1. A rotor of a motor comprising: a ring magnet having an insertion hole passing through a center thereof; a shaft inserted into the insertion hole; a coating material that covers an outer circumferential surface of the ring magnet; and a resin that covers an area between an inner circumferential surface of the insertion hole and the shaft, an upper surface of the ring magnet, and a lower surface of the ring magnet, the ring magnet having at least one first recess provided in the upper surface thereof, wherein the at least one first recess includes a bottom surface connected to the insertion hole and a sidewall that connects the bottom surface of the at least one first recess with the upper surface of the ring magnet, and the at least one first recess widens from the bottom surface towards the upper surface of the ring magnet, wherein a distance that extends radially from an inner surface of the insertion hole to the outer circumferential surface of the ring magnet is greater than a distance that extends radially from an outermost circumferential surface of the shaft to the inner surface of the insertion hole, wherein a distance that extends radially from a center of the shaft to an outermost end of the resin that extends to the upper surface and the lower surface of the ring magnet is greater than a distance that extends radially from the center of the shaft to an outermost end of the at least one first recess, and wherein the coating material includes Teflon and has a thickness of 10 μm to 30 μm.