Patent ID: 6305336
Filing Date: 2001-10-23
Classification: F01L

Abstract:
An electromagnetic device for driving an engine valve in an internal combustion engine,the valve comprising a stem defining along its longitudinal dimension a movement axis and having at one end thereof a valve portion that engages a valve seat for closing and opening an exhaust passage, comprising:an armature mechanically coupled to the valve stem;an electromagnetic driving mechanism comprises first and second electromagnets, disposed on opposite sides of the armature and being separately operable to magnetically engage the armature;a follower member, having first and second follower surfaces that are opposite to each other disposed along the movement axis and being coupled with the valve stem and the armature;first and second cams having gradually varied profiles and being pivoted for contacting, respectively, the first and second follower surfaces;first and second springs operative to urge the first and second cams toward the first and second follower surfaces, respectively; anda controller operative to selectively energize the electromagnets in accordance with an engine condition for controlling a movement of the armature.