Patent ID: 6348746
Filing Date: 2002-02-19
Classification: H02K

Abstract:
A slider unit with a built-in moving-coil linear motor, comprisinga bed supporting thereon a magnet yoke, a table movable through linear motion guide units in a sliding manner with respect to the bed, end plates mounted to lengthwise opposing ends of the bed, each to each end, a pair of field magnets arranged on inwardly confronting surfaces of the magnet yoke in such a manner that poles on the field magnets alternate in polarity along a moving direction of the table and also unlike poles confront each other across an air gap between the field magnets, and a moving-coil assembly mounted to the table and provided with armature coils arranged in the air gap, wherein the moving-coil assembly moves together with the table by virtue of electromagnetic interaction of magnetic flux of the field magnets with current flowing in the armature coils, the magnet yoke is composed of a pair of confronting sections having thereon the field magnets, each to each section, and a connecting section to join the confronting sections to each other at their lengthwise edges extending along the moving direction of the table, and the moving-coil assembly extends into the air gap, with passing through a sidewise opening formed at another edges of the confronting sections extending along the moving direction of the table, and wherein the bed is composed of a bottom and a pair of upright walls rising at sidewise opposing sides of the bottom and extending along the moving direction of the table, and the magnet yoke is arranged such that any one of the confronting sections is mounted on the bottom while another of the confronting sections is spaced apart in substantially parallel with the bottom, with the connecting section extending in perpendicular to opposing surfaces of the confronting sections.