Patent ID: 8546987
Filing Date: 2013-10-01
Classification: H02K,Y10T

Abstract:
1. A brushless direct current motor for use in a HVAC system, comprising: a stator comprising a stator core, field windings wound on the stator core, a bushing, and a bushing holder for holding the bushing; and a rotor rotatably mounted to the stator, the rotor comprising a shaft rotatably supported by the bushing and adapted to connect with a valve adjuster of the HVAC system, and at least one permanent magnet fixed with respect to the shaft; wherein the bushing is a monolithic construction having two journal portions and one middle portion, the two journal portions being integrally formed at respective axial ends of the middle portion and supporting the shaft; the middle portion having an inner diameter larger than an outer diameter of the shaft at portions corresponding to the middle portion, so as to form a gap between the middle portion and the shaft; and wherein the journal portions are respectively located at two axial ends of the bushing, the outer diameter of each of the journal portions is smaller than the outer diameter of the middle portion, and a gap is formed between the bushing holder and each journal portion.