Intelligent ultrasonic wave liquid leveller with function of speed measurement

To adopt a pair of ultrasonic sensors, the one is fixed on the bottom of a sealed tank outside, which is used to measure a liquid level within tank, and the other is fixed on a side of the tank outside, which is used to measure the transmission speed of ultrasonic wave in liquid of tank . Thus to any liquid and whatever change of temperature, this method can accurately measure the speed of ultrasonic wave in liquid. Using the measured speed of ultrasonic wave, it can accurately measure the level of liquid. Owing to this method can directly measure the speed, the accuracy of measurement is improved. This method can avoid delay of thermistor used for temperature compensation.