| 摘要 |
PURPOSE:To enable detection of the level and quantity of liquid by changing the inside diameter of a flow pipe, by causing thereby the change in pressure in the pipe and by generating a sound from an air flow caused by the differnce in pressure. CONSTITUTION:The pessure in a small pipe part 2 lowers when fluid 1 passes affluently through a pipe having a changed inside diameter. When an air path 3 is provided to communicate with the outside air 5 at this part, the outside air 5 enters therethrough, whereby a sound is generated by a sound source 4 fitted to the intermediate part of the path. When liquid is supplied from a pipe having an outlet 6 with larger diameter than that of the small pipe part 2, the sound is not generated until the level of the liquid reaches the outlet 6. And when the outlet 6 is placed in a state that the flow is affluent by the further rise of the level, the pressure in the small pipe part 2 falls and thereby the sound is generated. Moreover, by increasing or decreasing gradually the diameter of the pipe between the small pipe part 2 and the outlet 6 through the intermediary of a large pipe part 10' and the second small pipe part 2', the inside of the pipe is made affluent with flow in a short section, whereby the flow is changed smoothly. By this constitution, the level of the liquid is detected simply and the turbulence at a part having difference diameter is prevented. |
