| 摘要 |
<p>PURPOSE:To make temperature distribution uniform regardless of the amount of intake air by providing a plurality of bridge circuits, and controlling a flow speed detecting body and an adjusting resistor which is arranged at the neighboring position of the detecting body at specified temperature with the respective circuits. CONSTITUTION:Bridge circuits 10 and 20 are connected in parallel. A Wheatstone bridge is formed of the resistances of adjusting resistors 22 and 23 and a fixed resistance. The circuit 10 also has the same constitution. When an intake air is introduced into an air inlet tube, the quantity of heat in a flow-speed detecting resistor 13 is removed, and the constant temperature difference is kept. Therefore, the further supply of a current is requested. When the temperature of the resistor 13 becomes lower than the constant temperature difference in the circuit 10, the resistance becomes small, and the balanced condition of the bridge collapses. A current is supplied to the resistor 13. At this time, the same operation is performed in the circuit 20. Thus, the temperature of a resistor 12 which is arranged at the neighboring position of the resistor 13 is controlled. In this way, the circuits 10 and 20 keep the temperature difference of the resistors 12 and 13 constant, and the temperature distribution can be made uniform regardless of the amount of the intake air.</p> |
