Patent ID: 7042321

Claim:
An electromagnetic actuator comprising: an actuator member connected to an armature which is movable under drive from a drive member comprising at least one coil for generating magnetic flux in a core having a face facing a face of the armature, at least one of the facing faces including at least one set-back portion, wherein the armature and the core are arranged, in a first zone of the armature and of the core including the set-back portion, to define a first magnetic path which is interrupted by an air gap that is not less than the setback of the set-back portion when the armature bears against the core, and in a second zone of the armature and of the core excluding the set-back portion, to define a second magnetic path which is interrupted solely by a residual air gap when the armature bears against the core, and wherein the total area of the set-back portion is no greater than an area that would bring the magnetic flux to saturation in the second zone of the armature.