| 摘要 |
<p>PURPOSE: To obtain a thermal flow rate sensor for detecting the presence of flow stably of any liquid having different temperature by connecting a resistor element tar correcting the temperature rise in series with a resistor element for detecting the water temperature configuring a bridge circuit on the outside of a liquid channel. CONSTITUTION: A bridge circuit measuring the current variation of a resistor element 3 for detecting the flow rate comprises a series circuit of a resistor element 2 (resistance R4) for detecting the water temperature and a resistor element 8 (resistance R5) for correcting the temperature rise, an element 3 (resistance R3), and two fixed resistor elements (resistances R1 and R2) disposed on the outside of a fluid channel. In such bridge circuit, the element 2 has same temperature as a fluid F when the fluid F is stationary and the element 3 is heated. Since the elements 2 and 3 have different temperatures, they exhibit slightly different resistances to cause a micro potential difference between V1 and V2 which is corrected by connecting the elements 8 in series with the element 2.</p> |
