Electromagnetic actuator

Abstract

An electromagnetic actuator includes a magnetic flux conductive material case, an electrical current conductive coil, a magnetic flux conductive material core, and a pair of radially polarized magnetic flux developing elements. The coil is disposed in the case coextensively adjacent to its interior wall. The core is movably received within the chamber with motion of the core occurring between the first end and the second end of the case such that a first region of the core traverses the coil between its first end and its midpoint, and a second region of the core traverses the coil between its second end and its midpoint. A first one of the magnetic elements is carried by the first region and a second one of the magnetic elements is carried by the second region so that magnetic flux across the coil between the first region and the case is in a first direction, and magnetic flux across the coil between the second region and the case is in a second direction. The coil is arranged so that an electrical current in the coil between the first coil and the midpoint flows in an opposite direction with respect to the direction of the current in the coil between the second coil and the midpoint. Therefore, the flux current cross product of the flux in the first direction with the coil current and the flux current cross product of the flux in the second direction with the coil current are additive.