| 摘要 |
<p>PURPOSE:To simplify maintenance without need for providing any electric contact point on a truck and a machining station to send and receive electric signals by providing a reading means and an air pressure source near a conveying truck. CONSTITUTION:Compressed air which is fed to a compressed air intake 17a through a quick joint 34a flows through a piping 20 from the first port 11a of each limit valve 11 to its second port 11b, and then, flows through pipings 23, (25) into the head-side cylinder chambers of corresponding small cylinders 13b, 13d, causing the piston rods 14b, 14d of the small cylinders 13b, 13b, 13d to be projected. Each projection is read by the corresponding photo-tube type sensors 32b, (32d) respectively. And, when secure operation of the whole clamp unit 8 is ensured, the quick joints 34a, 34b are disconnected from the compressed air intakes 17a, 17b, and a truck 1 is transported to a welding line to machine a workpiece.</p> |
