Patent ID: 7220090

Claim:
A linear motor actuated machine tool comprising: a bed; a vertically extending column mounted on the bed; upper and lower X-axis guides extending in a horizontal direction and attached to upper and lower portions of a front surface of the column, wherein the front surface of the column extends in a plane parallel to the X-axis and the Y-axis; a saddle mounted on the front surface of the column such that a rear surface of the saddle faces the front surface of the column and so as to be guided by the upper and lower X-axis guides, the saddle having a through space at the center portion thereof; upper and lower X-axis linear motor magnets fixed on the front surface of the column at a respective upper side and lower side of the upper and lower X-axis guides in the direction of the X-axis such that pole surfaces thereof face frontward; upper and lower X-axis linear motor coils respectively fixed to an upper end and a lower end of the rear surface of the saddle so as to oppose the upper and lower X-axis linear motor magnets; right and left vertically extending Y-axis guides attached to a front surface of the saddle at both sides of the through space, wherein the front surface of the saddle extends in a plane parallel to the X-axis and the Y-axis; a slide mounted on the front surface of the saddle such that a rear surface of the slide faces the from surface of the saddle and so as to be guided by the right and left Y-axis guides; right and left Y-axis linear motor magnets fixed on the front surface of the saddle at a respective right side and left side of the right and left Y-axis guides in the direction of the Y-axis such that pole surfaces thereof face frontward, wherein each of the right and left Y-axis linear motor magnets comprise plural magnet pieces; right and left Y-axis linear motor coils respectively fixed to a right end and a left end of the rear surface of the slide so as to oppose the right and left Y-axis linear motor magnets; a spindle being capable of attaching the tool; a spindle head rotatably supporting the spindle and integrally fixed to the slide, and whose back end expands toward the though space; a table mounted on the bed at a location facing the front surface of the saddle to be movable in the direction of the Z-axis which is perpendicular to the X-axis and Y-axis, and on which a workpiece may be mounted, wherein a center of the right and left Y-axis linear motor coils in the direction of the Y-axis is upwardly spaced from a rotating center of the spindle.