SOUND-GENERATING METHOD UTILIZING DIFFERENCE IN PRESSURE BETWEEN INSIDE AND OUTSIDE OF FLOW PIPE, INFORMING DEVICE FOR LEVEL AND QUANTITY OF LIQUID AND METHOD FOR MAKING AFFLUENT IN SHORT SECTION FLOW AT OUTLET WHERE SIZE OF PIPE CHANGES FROM SMALL TO LARGE

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.