Valve stepping drive apparatus

Abstract

A valve stepping drive apparatus opens the suction/exhaust valve of an engine by an electromagnetic force generated by an electromagnet. A freely reciprocatable movable permanent magnet having at least a pair of magnetic poles arrayed in the direction of reciprocation is connected to the suction/exhaust valve, and fixed magnetic poles opposing the magnetic poles of the movable permanent magnet are provided and similarly arrayed in the direction of reciprocation. The suction/exhaust valve is driven, to open and close the same, by electromagnetic attractive and repulsive forces acting between the magnetic poles of the movable permanent magnet and the fixed magnetic poles. The actual operating state of the suction/exhaust valve is sensed, and when the operating state differs from a control command, the suction/exhaust valve is forcibly closed and self-diagnosis is performed.

Dependencies are inferred from the claim text.