摘要 |
A pair of jaw components 7a and 7b positioned on both sides of a casing 1 are attached to both the tips of a pair of parallel piston rods 6a and 6b which synchronously extend and contract in opposite directions by an action of an air pressure and the tips of a pair of guide rods 13a and 13b which synchronously extend and contract in opposite directions by a rack-and-pinion mechanism. By forming a magnetic scale 18 on a side face of one of the guide rods, 13b, the guide rod 13a is also used as a part of a dimension measuring mechanism. A sensor unit 20 for reading the magnetic scale 18 is attached to the casing 1. |