| 摘要 |
<p>PURPOSE:To improve the precision and response of an air-flow-rate measuring device by winding a thermoelectric heater wire and a temperature dependent resistance wire around the 1st supporter and a temperature-dependent resistance wire around the 2nd supporter while contact parts are reduced. CONSTITUTION:In a flow-rate measurement tube where gas to be measured flows, two supports each made of an electric insulator are provided, and each support is equipped with support rods; and one support is wound with a thermoelectric heater wire and a temperature-dependent resistance wire, and the other with only a temperature-dependent resistance body whike contact parts are reduced. For example, supports 18 and 19 each having four support rods 182 and 192 are arranged in a measurement tube; the former is wound with a thermoelectric heater wire 12 and a temperature-dependent resistance wire 13, and the latter with a temperature-dependent resistance wire 14 as shown in the figure. Consequently, the thermal loss from a heater to the supports is reduced, and from the current value for heating the heater required to hold constant atemperature difference between the temperature- dependent resistance wires, the quantity of air flow is measured with excellent precision and response.</p> |
