PURPOSE:To obtain a differential pressure type flow rate transducer, which can detect a flow rate highly accurately, by transducing differential pressure determined by the flow rate, into an electric signal through electrostatic capacitors, and correcting the signal with temperature pressure. CONSTITUTION:In a differential capacitance sensor 20, electrodes 21 and 22 are provided so as to face each other with respect to a moving electrode 23. The space between the electrodes is filled with sealed liquid 25. Electrostatic capacitances C1 and C2, which are differentially changed with differential pressure that is yielded by the detected flow rates, are formed. A liquid temperature sensor 26 detects the temperature of the sealed liquid 25. A temperature sensor 27 detects the temperature of fluid. An operating part 28 comprising a CPU 38 and the like operates the difference between the sums of the capacitances C1 and C2 and outputs a signal corresponding to said differentials pressure. Then, the product of the sums is operated. A signal corresponding to the dielectric constant of the sealed liquid 25 is outputted. Static pressure, which is applied to the sealed liquid 25, is computed based on the dielectric constant signal and the liquid temperature signal Td. The effects of the differential pressure of said differential pressure signal and the temperature signal Tf are corrected based on the signal corresponding to the static pressure and the signal Td. Then the temperature pressure is corrected with the signal Tf and the static pressure signal and standard temperature and standard static pressure. The result is multiplied by a flow rate coefficient, and a flow rate signal is obtained.
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