Patent ID: 7284424

Claim:
A thermal air flow rate measuring apparatus comprising at least one heating resistor disposed in a gas fluid; temperature detecting resistors each formed at an upstream part and a downstream part of said heating resistor in a direction of said fluid; means for outputting at least two signals relating to a flow rate of said fluid from said heating resistor and from said temperature detecting resistors; means for quantizing said output values; means for operating said at least two quantized signals using at least two parameters; and a means for synthesizing operated signals and outputting the synthesized result, wherein said two signals relating to said flow rate are signals relating to a heat generating value of said heating resistor and to a temperature difference between said temperature detecting resistors formed at the upstream part and the downstream part and wherein a plurality of said quantized signals is adjusted by a plurality of parameters expressed by a function of at least a first order equation, and said adjusted signals are individually multiplied as output.