Abstract: An electromagnetically actuator is disclosed having an electromagnet, a core element, the core element having a normally biased initial spaced apart first position distal from the electromagnet when the electromagnet is off and a second stop position proximal from the electromagnet when the electromagnet is on, a first resilient member adapted to bias said core element in the normally biased first position, and a second resilient member adapted to bias the electromagnet away from the core. The first resilient member is more resilient than the second resilient member. Therefore, the core approaches the electromagnet when the electromagnet is on until the core reaches the fixed stop position, and the electromagnet subsequently approaches the core to the fixed stop position. The actuator may further include an adjustment member that engages the electromagnet so as to control the pressure of the electromagnet against the second resilient member, whereby the axial position of the electromagnet is controlled.

Abstract: A field coil actuator includes a magnetic flux conductive material case, an electrical current conductive field coil and two electrical current conductive moving coils uniquely arranged. The case has a first surface and a continuous channel disposed in said first surface. The channel has a pair of opposing walls. The field coil is disposed within the channel between the walls so that a gap remains between the walls above the field coil and another gap remains between the walls below the field coil. When a current is induced in the field coil, magnetic flux is developed across the gaps. The flux is confined substantially normal to the walls of the channel. The electrical current conductive moving coils are each disposed moveably in one of the gaps such that an electrical current in the coil develops a Lorentz force on each of the coils in a direction substantially normal to the current in the moving coil and the magnetic flux to displace the moving coil in response to the current in the moving coil.

Abstract: An improved electromagnetic actuator includes a first assembly, a second assembly disposed for relative movement with respect to the first assembly and at least a first flexure interconnecting the first assembly and the second assembly. The first assembly includes a core having a first magnetic pole of a first polarity in a second magnetic pole of a second polarity. The second assembly includes an electrical current conductive coil having a first coil portion and a second coil portion. The first magnetic pole is in a facing relationship to the first coil portion and the second magnetic pole is in a facing relationship to the second coil portion. The first coil portion and the second coil portion are arranged so that an electrical current in the coil develops added a flux current cross products at each of the first coil portion and the second coil portion. One of the first assembly and the second assembly includes a magnetic flux return path between the first coil portion and the second coil portion.

Abstract: An electromagnetically actuator is disclosed having an electromagnet, a core element, the core element having a normally biased initial spaced apart first position distal from the electromagnet when the electromagnet is off and a second stop position proximal from the electromagnet when the electromagnet is on, a first resilient member adapted to bias said core element in the normally biased first position, and a second resilient member adapted to bias the electromagnet away from the core. The first resilient member is more resilient than the second resilient member. Therefore, the core approaches the electromagnet when the electromagnet is on until the core reaches the fixed stop position, and the electromagnet subsequently approaches the core to the fixed stop position. The actuator may further include an adjustment member that engages the electromagnet so as to control the pressure of the electromagnet against the second resilient member, whereby the axial position of the electromagnet is controlled.

Abstract: A voice coil actuator includes a magnetic flux conductive material core, a magnet and an electrical current conductive coil. The core has a first surface and a continuous channel disposed in said first surface. The channel has a pair of opposing walls. The magnet is disposed in intimate contact with a first one of said walls and spaced from a second one of said walls so that a gap remains between the magnet and the second one of the walls. The magnet has a first face of a first magnetic polarity facing the first one of the walls and a second face of a second, opposite magnetic polarity facing the gap. The magnet is further spaced from a bottom of the channel so that magnetic flux is substantially normal from the second face across said gap to the second one of the walls.

Abstract: A voice coil actuator includes a magnetic flux conductive material core, a magnet and an electrical current conductive coil. The core has a first surface and a continuous channel disposed in the first surface. The channel has a pair of opposing walls. The magnet is disposed in intimate contact with a first one of the walls and spaced from a second one of the walls so that a gap remains between the magnet and the second one of the walls. The magnet has a first face of a first magnetic polarity facing the first one of the walls and a second face of a second, opposite magnetic polarity facing the gap. The magnet is further spaced from a bottom of the channel so that magnetic flux is substantially normal from the second face across the gap to the second one of the walls.

Abstract: An improved electromagnetic actuator includes a first assembly, a second assembly disposed for relative movement with respect to the first assembly and at least a first flexure interconnecting the first assembly and the second assembly. The first assembly includes a core having a first magnetic pole of a first polarity in a second magnetic pole of a second polarity. The second assembly includes an electrical current conductive coil having a first coil portion and a second coil portion. The first magnetic pole is in a facing relationship to the first coil portion and the second magnetic pole is in a facing relationship to the second coil portion. The first coil portion and the second coil portion are arranged so that an electrical current in the coil develops additive flux current cross products at each of the first coil portion and the second coil portion. One of the first assembly and the second assembly includes a magnetic flux return path between the first coil portion and the second coil portion.

Abstract: An electromagnetic actuator includes a magnetic flux conductive material housing, an electrical current conductive coil, a magnetic flux conductive material stationary core portion, a slideable core portion, and a pair of radially polarized magnetic flux developing elements. The coil is disposed in the housing coextensively adjacent to the housing's interior wall. The core is disposed within the housing and the coil and includes both the magnetic flux conductive stationary core portion and the slideable core portion. The slideable core portion is slideably received on the stationary core portion, and the magnetic flux developing elements are carried on the exterior wall of the slideable core portion in a facing relationship with the coil.

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.

Abstract: An improved electromagnetic actuator of the type comprising (a) a first assembly; (b) a second assembly movable relative to the first assembly along an axis of relative movement in response to a command signal, the second assembly comprising magnetic flux source means for defining radially directed flux both in an inward and outward direction relative to the axis of relative movement; (c) coil assembly means for defining at least two coil segments respectively disposed in the paths of the flux in the inward and outward directions; and (d) means for applying the command signal to the coil segments so that a current flows in one direction around the axis through the inward directed flux, and flows in the opposite direction around the axis through the outward directed flux so that the flux/current force applied between the first and second assemblies is additive. In accordance with one aspect of the invention flat magnets and flux focussing elements are used to provide the radially directed flux.