Method of measuring a valve play of an engine-cylinder valve operated by an electromagnetic actuator

A method of measuring a valve play in a reciprocating valve having open and closed positions and being operated by an electromagnetic actuator including an opening electromagnet, a closing electromagnet, an armature movable between pole faces by electromagnetic forces against a spring force of return spring means for moving said valve into an open position;

• said valve play being defined by a clearance between said armature and said valve when said armature is in contact with the pole face of said closing magnet and said valve is in said closed position;
• the method comprising the following steps:
• (a) detecting a motion of the armature within said clearance as a function of at least one of a course of voltage and a course of current in said closing electromagnet;
• and
• (b) deriving the size of said valve play from an irregularity in at least one of said course of voltage and said course of current;
• said irregularity being caused by an impacting of said armature on at least one of said valve and said pole face of said closing electromagnet.