Patent ID: 6230674
Filing Date: 2001-05-15
Classification: F01L,H01F

Abstract:
An electromagnetically driven valve for an internal combustion engine, comprising:an armature coupled to a valve body of an exhaust valve of the engine for reciprocal movement therewith between an open and a closed position;a first elastic member coupled to the armature to bias the armature toward the open position and a second elastic member coupled to the armature to bias the armature toward the closed position, wherein a neutral position of the armature is defined between the open and closed positions at a point where forces applied by the first and second elastic members balance one another; anda first electromagnet adjacent to the open position and a second electromagnet adjacent to the closed position, wherein the first and second electromagnets are positioned so that, when the armature is in the neutral position, the first and second electromagnets are spaced apart from the armature, and wherein the neutral position is closer to the first electromagnet generating an electromagnetic force attracting the armature toward the open position,wherein the second electromagnet generates an electromagnetic force attracting the armature toward the closed position, andwherein an energy stored in the first elastic member when the armature is in the closed position is larger than an energy stored in the second elastic member when the armature is in the open position.