| 摘要 |
The actuator, hydraulic or pneumatic, comprises a body composed of concentric tubes 10, 12 which are spaced to define a passage 38 through which fluid is fed from a valve block at one end of the actuator to the end of the actuator remote from the valve block to obviate the need for external piping. The piston rod 16 of the actuator also comprises a tube and receives a position-sensing transducer 20, 24, e.g. having a potentiometer, which is exposed by fluid in one chamber defined by the piston 18 and the body. <IMAGE> |
