BRUSHLESS DC MOTORS WITH REMOTE HALL SENSING AND METHODS OF MAKING THE SAME

摘要

A brushless DC motor apparatus includes a housing and a stator assembly coupled to the housing. The apparatus further includes a magnetic rotor assembly configured to rotate within the housing in response to electric currents through windings of the stator assembly. The apparatus further includes position sensors which are configured to provide position signals identifying angular position of the magnetic rotor assembly relative to the stator assembly. Each position sensor includes (i) a Hall-effect sensor disposed distally from the windings, and (ii) magnetic circuit members having first end portions adjacent the windings and proximate rotor magnets and second end portions adjacent the Hall-effect sensor. Use of such magnetic circuit members enables the Hall-effect sensors to reside a greater distance from the windings vis-à-vis conventional brushless DC motors which position sensors adjacent to stator coils within motor casings.