Patent ID: 6034856
Filing Date: 2000-03-07
Classification: F01L

Abstract:
A method of recognizing the contact of an armature against a pole face in an electromagnetic actuator for activating a setting member, with the actuator having at least one electromagnet, which is supplied with a clocked current by a control device, and whose armature is in operational connection with the setting member and can be brought out of a first set position, counter to the force of a restoring spring, and brought into contact with the pole face of the electromagnet and held when the electromagnet is supplied with current, said method comprising detecting the controlled (clocked) current course for the holding phase during the time provided for armature contact; converting the detected current into a current-proportional voltage; differentiating the converted current-proportional voltage; and detecting the differentiated converted voltage as a recognition signal, both for the normal condition of ""armature in contact"" and the fault condition of ""armature not in contact.