Patent ID: 7969705
Filing Date: 2011-06-28
Classification: H01F

Abstract:
1. A controller for a brake or clutch having a core housing defining a first surface, a coil, and an armature defining a second surface, at least one of the core housing and armature rotatable with respect to the other of the core housing and armature about an axis to transfer torque therebetween in a braking or clutching action, the controller comprising: a processor connected to the coil; the processor causing a magnetization current to be provided to the coil to create a substantially closed magnetic path with flux lines extending between the second surface of the armature and the first surface of the core housing separated by an air gap of 0.005 inches or less in order to create an irreversible residual magnetic force with a residual magnetic air gap energy of at least 6700 (line-amp-turn)/cm