| 摘要 |
<p>PURPOSE:To measure a mass flow rate of a fluid linearly, by a method wherein a difference between electric resistors wound round on a conduit is adjusted to be proportional precisely to the mass flow rate of the fluid flowing through the conduit. CONSTITUTION:A differential amplifier 20 outputs a potential difference between a potential at the node of a resistance 1 and a resistance 2 and a potential at the node of two resistors A and B. An output E of the differential amplifier 20 is expressed as E=c[(RA-RB)i/2]=c(DELTARi/2) [(c) is an amplification constant] and is proportional to a difference AR in electric resistance between the two resistors A and B. Thus, the output E of the differential amplifier 20 is proportional to the difference DELTAR, and by adjusting a variable resistance Rk of a proportional multiplication circuit 21, an output E+(kE)<2> of a multiplier 22 can be made proportional to flow rate Q. By adjusting the variable resistance Rk beforehand, therefore, the mass flow rate Q of a fluid F flowing through a conduit T can be measured linearly with excellent precision.</p> |
