| 摘要 |
PURPOSE:To correctly open and close a valve and supervise leakage with an acoustic sensor by providing a supervisory device with a densitometer for discriminating water from vapor and opening and closing a valve and supervising leakage on the basis of a decision signal and an acoustic sensor output. CONSTITUTION:An acoustic sensor 2 detects an acoustic signal generated when a fluid passes a valve 1, and an output signal is input to a preliminary processing circuit 4. After processings such as amplifying, removing noise and so on, the signal is input to a signal processing portion 6. A densitometer 3 and the processing device 5 examine whether a fluid flowing through the valve 1 is water or vapor, and an output signal is input to the processing device 5 to be compared with a preset value, thereby deciding whether the fluid is water or vapor. The decision signal is sent with an acoustic signal to the signal processing portion 6. The processing portion 6 is adapted to detect opening and closing of the valve 1 and a leakage condition on the basis of the scale of the acoustic signal and the decision signal indicating the kind of fluid. In this arrangement, even if a fluid is water or vapor, the opening and closing of the valve 1 and leakage condition can be detected with high accuracy. |
