LIQUID LEVEL MEASURING METHOD BY ULTRASONIC ECHO AND FLOW VELOCITY MEASURING METHOD AND THICKNESS MEASURING METHOD FOR LIQUID LAYER, AND ULTRASONIC TRANSDUCER USED FOR THESE METHODS

摘要

PURPOSE:To measure a liquid level by arranging an ultrasonic transducer on the bottom face of a container of a liquid to be measured, outgoing an ultrasonic wave to the liquid level of the liquid and receiving its echo. CONSTITUTION:As for an ultrasonic transducer 20, an oscillator 22 having a silicon film 23 is attached to a base 26 through a cushion part 24. Therefore, the oscillator 22 is pressed against to the bottom face of the outside of a bottle 10. At the time of measuring the liquid level, an ultrasonic wave is originated to the liquid level 14 of the liquid 12 in the container 10 from the ultrasonic transducer 20. An echo wave 30 reflected by the liquid level 14 is received by the same ultrasonic transducer 20. In this case, by counting the time required extending from the origination to the reception, the liquid level can be measured. The liquid level which is measured can be displayed by an analog or digital indicator.