Internal combustion engine lifting valve electromagnetic actuator has pneumatic restoring spring vented to atmosphere in unloaded position, compresses air vol. during armature capture

摘要

The actuator has restoring springs with a progressive characteristic so that the magnetic force of the electromagnetic carrying a current, and hence capturing the armature, is never lower than the force of the restoring spring opposing the attraction. The restoring spring is a pneumatic spring element that is vented to atmosphere in the unloaded position. During the capturing process an air vol., which can be partially displaced via suitable choke bores (4a,4b) from the pneumatic spring element, is at least partly compressed.