Actuators and apparatus
OwnerKari M Ullakkoinventor
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Abstract
The present invention relates to actuators, linear motors and rotational motors based on magnetic-field-induced strains taking place in the actuator material. These strains are caused by the reorientation of the twin structure of the actuator materials by the applied magnetic field.
Claims82
An apparatus comprising an active element made from a material having variants separated by a twin boundary, the active element having a shape, the material having both an energy needed to reorient the variants and a magnetocrystalline anisotropy energy, the magnetocrystalline anisotropy energy being sufficient with respect to the energy needed to reorient the variants to change the shape of the active element in response to a predetermined vector force of an external magnetic field, wherein the shape of the active element is coupled to the external magnetic field.
An apparatus according to claim 48, wherein the actuating element is an open loop that forms a flux path for the driving magnetic field, and wherein the magnetic field is led to the loop by an external magnetic field whose intensity and direction are suitable to cause a desired shape change of the loop.
Dependencies are inferred from the claim text.