Electromechanical variable valve actuator with a spring controller

Abstract

Actuators, and corresponding methods and systems for controlling such actuators, provide independent lift and timing control with minimum energy consumption. In an exemplary embodiment, an electromechanical actuator comprises a housing, first and second electromagnets rigidly disposed in the housing and separated from each other by an armature chamber, an armature disposed in the armature chamber and movable between the first and second electromagnets, an armature rod rigidly connected with the armature and operably connected with a load, at least one first actuation spring biasing the armature in a first direction, at least one second actuation spring biasing the armature in a second direction, and one fluid-operated spring controller capable of controlling the position of the first-direction end of the at least one second actuation spring. The spring controller allows the actuation springs at their least compressed state and the engine valve closed when engine power is off. The spring controller may also be adjusted, with a low or moderate control fluid pressure, to allow the engine valve to operate with a partial lift.

Dependencies are inferred from the claim text.