| 摘要 |
Thermal flow sensor (1) for determining the flow rate of a medium (2), having: a substrate (3); a first and second temperature sensor (4a, 4b) which are arranged on the substrate (3), wherein the first and second temperature sensors (4a, 4b) are in the form of heatable temperature sensors (5a, 5b) or in the form of a first non-heatable temperature sensor (6a, 6b) which has an associated first heating element (7a), and in the form of a second non-heatable temperature sensor (6b) which has an associated second heating element (7b); a feed unit (8) which supplies a first heating power, which is predetermined during a comparison operation, to the first heatable temperature sensor (5a) or to the first heating element (7a) by means of a first signal (9a), and supplies a second heating power, which is predetermined during the comparison operation, to the second heatable temperature sensor (5b) or to the second heating element (7b) by means of a second signal (9b); an evaluation unit (10) which determines a temperature difference (ΔT) between the first temperature sensor (4a) and the second temperature sensor (4b) during a measurement operation in order to determine the flow rate of the medium (2), and determines a measurement value, which represents the flow rate of the medium (2), on the basis of the temperature difference (ΔT). |
