Patent ID: 6995490
Filing Date: 2006-02-07
Classification: H02K

Abstract:
1. A method of controlling speed of a permanent magnet DC motor, the motor including an armature having a lamination core and windings; and a stator structure associated with the armature, the armature being constructed and arranged to rotate with respect to the stator structure, the stator structure including at least two permanent magnets of the same polarity that provide a certain flux; and at least two wound core structures of the same polarity, each wound core structure having a core and a coil wound about the core, the wound core structures defining alternate poles with respect to the permanent magnets, the method including: providing switches operatively associated with the motor and coils, and controlling the switches to so that 1) no current is provided to the coils so that the armature rotates at a certain speed based on the certain flux of the permanent magnets, 2) current is provided to certain of the coils in one direction so that flux increases relative to the certain flux, causing the armature to rotate at a speed less than the certain speed or 3) current is provided to certain of the coils in a direction opposite the one direction so that flux decreases relative to the certain flux, causing the armature to rotate at a speed greater than the certain speed.