Patent ID: 8110950

Claim:
A coreless linear motor comprising: a fixed member functioning as a stator; and a movable member functioning as an armature; the fixed member having a yoke and first and second groups of permanent magnets fixed to the yoke; the movable member having a coil assembly having an inner shape of a rectangle and a reinforcing member, the reinforcing member having an outer shape of a rectangle on which the coil assembly is fittingly mounted, the reinforcing member extending in a longitudinal direction of the linear motor, being not positioned in the magnetic field between the coil assembly and the first and second groups of permanent magnets, being made of a nonmagnetic, electrically and thermally conductive material, conducting the heat generated in the coil assembly to an outside, and being formed without any hollow or cavity for increasing the rigidity of coil assembly; the yoke having first and second facing yoke parts facing each other across a first distance and formed by magnetic material and a connection yoke part connecting first ends of the first and second facing yoke parts to define a space through which the movable member is movable, the first, second and connection yokes being formed by magnetic material; the first and second groups of permanent magnets being arranged so as to face the facing surfaces of the first and second facing yoke parts, each of the first and second groups of permanent magnets having different magnetic poles alternately arranged, along the longitudinal direction of the yoke, and the facing magnetic poles of the permanent magnets along the longitudinal direction of the yoke being the same; the coil assembly having at least three coils, continuously arranged, functioning as three phase coils, and wound in a same direction having a hollow shape and rectangular or square outer shape, the nonmagnetic reinforcing member being fitted into the hollow shape, and arranged movably relative to the first and second groups of permanent magnets along the longitudinal direction of the yoke; each coil being wound in a cylindrical form by a conductive metal wire; the at least three coils being arranged in multiple layers, then fastened by a binder, the end surfaces of adjacent coils connected with each other via an electrical insulation member; the coil assembly and reinforcing member moving in the space between the facing first and second groups of permanent magnets along the longitudinal directions of the yoke.