Abstract: A pneumatically movable device with a safety lock means having a movable member, a pneumatic actuator connected to the movable member and adapted to move the movable member and a direction control valve connected to the actuator. A cylinder for locking is connected between one of the ports of the cylinder and the direction control valve. A spring is disposed in the cylinder for locking. Openings provided at a chamber at a side of the spring are connected to the actuator and the directional control valve respectively through a check valve disposed for preventing the air from flowing into the cylinder for locking. Openings provided at a chamber at a side remote from the spring are connected to on one hand to the actuator through a check valve disposed for preventing the air from flowing into the cylinder for locking and on the other hand to the directional valve through the check valve with a restrictor disposed for preventing the air from flowing into the direction control valve.

Abstract: An apparatus connected to an arm in a robot system removes injection molded and die cast products while compensating for the load on the piston rods of the apparatus. A chuck for grasping the products is moved up and down by a pair of pneumatic cylinders on a frame and intermediate frame. The pneumatic cylinders carry the load of the various elements of the apparatus. In order to eliminate variations in the load carried by the cylinders and absorb the shock at the ends of the cylinder strokes, the apparatus includes surge tanks connected to the cylinders. Compressed air is provided through the surge tanks to provide an upward pressure offsetting the load on the cylinders.