| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain an output signal having a frequency dependent on a fluid medium by compensating in a voltage frequency conversion circuit a measured signal in which frequency is a measure of the fluid medium. SOLUTION: If a measured voltage UM is generated in a temperature difference bridge circuit DT and supplied to the voltage frequency conversion circuit UFW, a high temperature balance regulating part HTA takes out a balance regulating voltage UA through a potentiometer P2 and superimposes it on the measured voltage UM through a resistor R13 and supplies it for an operational amplifier OP4. The operational amplifier OP4 is connected to a heat regulating circuit HK and a comparator KP1 and the voltage frequency converter UFW1 is compensated by resistors R17, R18 connected to between an output side A of the circuit and the comparator KP1. A voltage UFA (whose frequency FA is dependent on a flow rate) is generated at the output side A. The operational amplifier OP4 is connected as an integrator and constitutes an oscillation system together with the comparator KP1.</p> |
