Patent ID: 6473286
Filing Date: 2002-10-29
Classification: F02D,H01H

Abstract:
A driving apparatus for an electromagnetic device comprising:a switching device provided in series with the electromagnetic device for supplying a conduction current to the electromagnetic device to drive the electromagnetic device when turned on; conduction period setting means for setting a conduction period of the electromagnetic device, the conduction period includes a first conduction period and a second conduction period following the first conduction period; and conduction control means for repeatedly turning on and off the switching device so as to set the conduction current at around a first predetermined current limit value during the first period of the conduction period, for repeatedly turning on and off the switching device so as to set the conduction current at around a second predetermined current limit value smaller than the first predetermined current limit value during the second period of the conduction period following the first period, and for completely turning off the switching device after the conduction period irrespective of the conduction current; wherein an on/off-time of the switching device in the second period is set longer than that in the first period.