摘要 |
<p>A variable reluctance motor (20) having improved means for detecting the relative position of the rotor (34) and stator (32) during rotation of the rotor whereby signals may be employed to commutate the motor, comprising sensed means on the rotor including four sets of elements, each set located within an arcuate length of 90° and each set having two sensed portions with leading edges in the direction of rotation being separated by alternating arcuate lengths of 30° and 60°. Sensing means comprising two sensors arcuately separated by 30° times n wherein n is 1, 2, 4, or 5 are located adjacent the path of rotation of the sensed elements. In a preferred embodiment, the sensed means is a permanent ring magnet (52) having unequal alternating arcuate North and South pole lengths, and the sensing means are two Hall effect sensors (56, 57). Commutation of a three-phase motor having four rotor poles (38) and six stator poles (36) can thus be effected with the use of only two sensors.</p> |