FLOW MEASUREMENT DEVICE

摘要

A flow meter device of a fluid includes a time difference measuring means (13) which measures time for a received wave to reach a zero cross point after the received wave exceeds a reference voltage, after transmission of a signal, and a reference voltage setting means (14) which changes the reference voltage from a minimum value to a maximum value, recognizes peak voltages of waves of the received wave based on a plurality of inflection points at which a time difference measured by the time difference measuring means (13) when the reference voltage is changed from the minimum voltage to the maximum voltage, is significantly changed, and automatically sets the reference voltage to a point between peak voltages of particular two waves based on a ratio between the peak voltages, and the reference voltage is changed from a voltage which is close to the peak voltages of the two waves and the peak voltages are newly recognized, when the reference voltage is newly set.