| 摘要 |
PURPOSE:To obtain an easy-to-fit detector without lowering its performance by uniting a current velocity detecting element and a fluid temperature measuring element by a member which cuts off heat conduction. CONSTITUTION:The current velocity detecting element 1 and fluid temperature measuring element 2 are surrounded with an alumina package 6 and a cap 7 which have good heat conductivity, both elements 1 and 2 are joined by a porous member 30 whose heat conductivity is <=0.1W/m. deg.C, and air 8 is charged in the elements 1 and 2 to make the element 2 hard to get affected by the heat of the element 1. The heat conduction distance may be increased for heat radiation by using a coiled element wire instead of the member 309. The voltage VBE9 of the transistor TR 9 of the element 2 and a voltage V2 obtained by adding the voltage drop across a resistance R2 to the voltage VBE4 of the TR 4 of the element 1 are inputted to an operation amplifier 11 and inputted to a heating TR 3 to adds rising temperature based upon the value of the resistance R2 to the fluid temperature; and the element 1 is made to generate heat higher than the fluid temperature, so that the value of heat absorbed from the element 1 which has a constant relation with the current velocity is detected by the TR 3.
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