Patent ID: 8796891
Filing Date: 2014-08-05
Classification: H02K

Abstract:
1. A brushless DC motor comprising: (a) a housing including: (b) a stator assembly disposed in the housing, comprising: (c) a rotor assembly rotatably disposed in the stator assembly, comprising: (d) a spacer ring disposed in the lower housing of the housing, wherein the spacer ring is engaged with the stator core and disposed between the stator core and the main plate of the lower housing in an axially direction; and (e) a circuit board mounted with an IC component to control a driving current, wherein the circuit board is secured to an outer face of the main plate of the lower housing, and the IC component mounted on the circuit board protrudes into the lower housing through one of the openings formed at the main plate of the lower housing, wherein the sleeve has an annular recess portion in its surface facing the IC component, and a part of the IC component is housed with the annular recess portion, and wherein the stator core has a plurality of axially-extending recesses provided at an outer circumference thereof, and wherein the spacer ring is provided with a plurality of axial-extending protrusions at an upper side and a lower side thereof, the plurality of protrusions provided on the upper side of the spacer ring are engaged with the plurality of recesses of the stator core, and the plurality of protrusions provided on the lower side of the spacer ring are engaged with the circuit board through the other opening formed at the main plate of the lower housing.