JPS6466532A - Wide-range pressure converter - Google Patents

Abstract

PURPOSE:To achieve a pressure measurement in a wide range from a very low to high level, by detecting an attenuation value of an ultrasonic wave when it is transmitted through a liquid to be measured. CONSTITUTION:An ultrasonic wave transmitter 2 for transmission and an ultrasonic wave receiver 3 for reception are arranged in a liquid to be measured facing each other. When a pulse voltage is applied to the device 2 from a pulser circuit 1, an ultrasonic wave transmitted from the device 2 is propagated being attenuated through a fluid and received with the device 3 to be converted into a pulse voltage. A peak value of the voltage is determined with a peak holding circuit 7. Then, as the peak value changes corresponding to a pressure of a fluid to be measured, a difference between the peak value and a pulse voltage outputted from the circuit 7 is determined with a comparator circuit12 and the results are computed with a pressure computing circuit 13 to enable the measuring of a pressure value of the fluid being measured. Thus, the pressure of the fluid can be measured from an attenuation of an ultrasonic wave to to the pressure of the fluid being measured, thereby permitting measurement of a pressure change in a wide range from a very low level such as 0.02kg/cm<2> to a high level such as several 10kgf/cm<2> or more.