Method for detecting liquid in gas return line by monitoring gas returning in refueling system during refueling of motor car, involves generating trouble signal when time course of sensor signal is higher than threshold level

摘要

The method involves detecting mass current i.e. mass of gas per time unit, of gas re-conducted with refueling processes by a thermal flow sensor (20) arranged at a gas return line (15). A heating device is arranged on the thermal flow sensor and is thermally contacted to a temperature sensor. A sensor signal is produced and transmitted to the heating device. A time course of the sensor signal is compared with a threshold level. A trouble signal is generated when the time course is higher than the threshold level. The presence of liquid in the return line is confirmed based on the trouble signal. An independent claim is also included for a device for detecting liquid in a gas return line by monitoring of gas returning in a re-fueling system.