The electromechanical actuator comprises a yoke, two permanent magnets, two
coils and a mover. The yoke and the mover are made of iron. Eddy currents in
the magnets and in the laminated yoke and mover are neglected. The permanent
magnets constitute a magnetic lock that keeps the mover either in the upper or
lower position tending to diminish the residual airgap. The mover is moved down
or up by applying a voltage pulse to one of the coils. The commutation is
facilitated by two springs.