| 摘要 |
PURPOSE:To simplify a device and to reduce its size by performing on-off control over a control valve with the output signal of a sensor used for measurement, and only arranging one sensor at both ends of the piston prover and performing the measurement and control over the valve. CONSTITUTION:Single sensors 5 and 5' which detect detected plates 4a and 4a' on driven levers 4 and 4' which slide in contact with a piston 3 are provided to sensor fitting pipes 1 and 1' fixed at both ends of a cylinder 2. Then when a switch SW is turned on, control valves 10 and 11 are opened and the fluid from the measurement part 8 of a flow meter to be inspected flows in the cylinder 2 to move the piston 3 to right. The sensor 5 detects the detected plate 4a to take a measurement. Further, the sensor 5' detects the detected plate 4a' to stop the counter of a display part 6 and also closes the valves 10 and 11 to stop the piston 3 near the left dead point of the cylinder 2. When the switch SW is turned on for calibration, the control valves 10 and 11 are changed over and opened to form the flow passage extending from the right end of the cylinder 2 to the left end, thus calibrating the flow rate. |
