| 摘要 |
<p>PURPOSE:To accurately measure the flow rate of a carrying fluid by compensating the electromotive force of a sensor produced by the pressure variation of the fluid. CONSTITUTION:Pressure variation produced by a change in the flowing direction of a jet stream from a jet nozzle 3 is detected with a sensor 14. Inside the sensor 14, a pressure chamber is divided into a central chamber 16a and 1st and 2nd end-section chambers 16b and 16c by means of 1st and 2nd piezoelectric films 15a and 15b and a feedback flow passage 7a is connected with the central chamber 16a and the 1st end-section chamber 16b by a conduit passage 13a. Another feedback flow passage 7b is connected with the 2nd end-section chamber 16c by another conduit passage 13b. A flow rate detecting section 18 detects the flow rate of the jet stream from the nozzle 3 in accordance with the difference between the signals from the 1st and 2nd piezoelectric films 15a and 15b and an abnormality detecting section 19 detects an abnormal state, such as occurrence of an earthquake, etc., in accordance with the signals from the 1st piezoelectric film 15a.</p> |
