Image Number 6 for United States Patent #5487580.
A chuck unit for automatically inserting a workpiece in a receiving portion, which comprises a fixed pawl, first and second movable pawls and a pusher. Both major surfaces of the workpiece are chucked by a first vertical surface of the fixed pawl and the first movable pawl, and both side edges of the workpiece are chucked by a second vertical surface of the fixed pawl being perpendicular to the first vertical surface and the second movable pawl. The pusher is vertically movable between the first vertical surface and the first movable pawl for downwardly extruding the workpiece. Since two major surfaces and two side edges of the workpiece are held by the pawls, the attitude and position of the workpiece are corrected therein. Therefore, this chuck unit is suitable for assembling a plurality of workpieces which are arranged in a thickness direction thereof in an aligned manner.