Patent ID: 7837027

Claim:
A workpiece conveying apparatus comprising: a conveyer stage having a conveying surface for conveying a workpiece; a conveyer table having a first surface facing the conveying surface of the conveyer stage and a second surface opposite the first surface, the conveyer table including through-holes that pass through the first and second surfaces; first means connected to the conveyer table and/or the conveyer stage for receiving a driving force so as to allow the conveyer table to move in sliding contact with the conveying surface of the conveyer stage with the first surface of the conveyer table facing the conveying surface of the conveyer stage; wherein the workpiece is conveyed by moving the conveyer table relative to the conveying surface with the workpiece disposed in one of the through-holes of the conveyer table, wherein a suction recess portion extending in a conveying direction of the workpiece is formed in the conveying surface of the conveyer stage in order to hold the workpiece disposed in the through-hole by suction, and an exhaust hole for discharging compressed gas when the workpiece to be picked up is conveyed, is formed in the conveying surface of the conveyer stage at a location at which the workpiece is picked up so as to be capable of overlapping with the through-hole in order to pick up the workpiece, and wherein a suction groove extending in a direction crossing the conveying direction of the workpiece is formed in the first surface of the conveyer table so as to communicate with the through-hole, and the conveyer table moves while sliding on the conveying surface of the conveyer stage with the suction groove communicating with the suction recess portion formed in the conveying surface of the conveyer table; second means for connecting a suction unit to the suction recess portion; and third means for connecting a compressed gas supply unit to the exhaust hole; wherein a pressure relief hole is provided in the conveyer table at a location downstream of the through-hole in the conveying direction and at which the pressure relief hole overlaps with the exhaust hole, and the pressure relief hole is open in the first surface of the conveyer table so as to communicate with the atmosphere when the conveyer table is moved.