Patent ID: 6536273
Filing Date: 2003-03-25
Classification: G01F

Abstract:
A thermal flow-rate sensor, comprising:a flow sensor having a first heating device and a first temperature detector reacting to the temperature of the first heating device, said flow sensor being exposed to a flowing fluid whose flow rate is to be determined, and a thermal-conductivity measuring cell having a measuring-cell casing, a second heating device and a second temperature detector reacting to the temperature of the second heating device, the measuring-cell casing having at least one opening arranged for entry of the fluid into the measuring-cell casing; and a control and evaluation device electrically connected to said thermal-conductivity measuring cell and said flow sensor for generating a first measuring signal, which characterizes a heat dissipation capacity of the fluid by heating power supplied to the second heating device and the temperature of the second temperature detector, and for generating a second measuring signal, which characterizes flow rate of the fluid by heating power supplied to the first heating device, the temperature of the first temperature detector, and the first measuring signal.