Thermal sensor arrangement for continuous liq. flow measurement - determines signal difference between heated thermo-sensor and temp. sensor

摘要

A thermal sensor arrangement for continuous liquid flow measurement or flow mass measurement is esp. useful in the fuel line of an internal combustion engine. The effects on measurement accuracy of flow disturbances near the sensor and of temp. effects are eliminated. An electronic circuit evaluates the difference between the signals from a heated thermal sensor in the flow path measuring its own temp. and a second temp. sensor in the flow path measuring the temp. of the liquid. The temp. sensor (15) is mounted downstream of the thermal sensor (14) in a chamber (12) contg. both sensors. The chamber is enclosed by a tube (18) in which the direction of flow is opposite to that within the chamber. The arrangement does not require moving parts with the associated friction inducing bearings.