Patent ID: 7116541
Filing Date: 2006-10-03
Classification: H01F,H01H

Abstract:
1. A method for reducing the switching noise of an electromagnetic switching device including a coil drivable by a supply voltage, and an armature adapted to move moving switching contacts into contact with stationary switching contacts, the method comprising: defining a first minimum value of the supply voltage, sufficient for at least moving the armature with the moving switching contacts; using a drive unit to drive the coil, and hence the armature, with the moving switching contacts by the first minimum value of the supply voltage, at least until contact is made; and increasing, as a function of time, the supply voltage from the first minimum value to a second minimum value, sufficient to move the switching contacts into sufficient mutual contact with the stationary switching contacts with pressure applied; wherein the drive unit includes a switching element for driving a voltage limiter; and wherein the switching element is an optocoupler.