Patent ID: 6633478
Filing Date: 2003-10-14
Classification: H01H

Abstract:
In an electromagnetic device with a coil in which the electromagnetic device is actuated with an actuating current and held in an operative condition by a holding current with the holding current being significantly lower in magnitude than the actuating current, a control circuit comprising:a first transistor disposable in one of an off state and an on state, said first transistor communicating with said coil; a second transistor disposable in one of an off state and an on state, said second transistor communicating with said coil, wherein during a powered mode, the first transistor is disposed in the on state and the second transistor is disposed in the off state, and, during a shorted mode, the first transistor is disposed in the off state and the second transistor is disposed in the on state; a power source selectively communicating with the coil, wherein, during a first time interval, said power source communicates with said coil in the powered mode and, during a second time interval, said power source is disconnected from said coil in the shorted mode so that current is recirculated by said second transistor; and a switching actuator communicating with said first and second transistors, said switching actuator operating cooperatively with the first and second transistors to transition the holding current from a first magnitude to a second magnitude while maintaining the electromagnetic device in the operative condition.