Linear drive for IC engine valve for vehicle includes two drive modules producing variable strength magnetic field for bi-directional valve displacement

摘要

The linear drive (110) comprises a fixed part (115) defining a passage for a mobile part (116). The mobile part has a permanent magnet, the magnetic axis of which is perpendicular to the axis of displacement (A). The fixed part (115) co-operates with at least two drive modules (120,130) which create a magnetic field of variable intensity in a direction perpendicular to the axis of displacement in a part of the passage defined by the fixed part. The fixed part (115) defines at least one passage in which the mobile part (116) is guided to slide between an extreme high position and an extreme low position. The mobile part is thus under the effect of magnetic attraction or repulsion forces arising from the interaction of the permanent magnetic field and the fields created by the drive modules (120,130), the direction and strength of the force being controlled by the magnetic fields created by the drive modules.