Patent ID: 7168314
Filing Date: 2007-01-30
Classification: G01F

Abstract:
1. Ultrasonic filling level sensor ( 1 ), having an elongated measuring chamber ( 2 ), which is provided with an opening ( 3 ) at each of its two ends and in which a liquid has the same filling level as outside the measuring chamber ( 2 ) and the emitted sound signals of which transceiver are reflected at the surface of the liquid and at a calibrating reflector ( 5 ) and received by the ultrasonic Transceiver ( 6 ), in order to determine the filling level from a relationship between the transit times of the two signals, wherein the cross-section of the measuring chamber ( 2 ) and the nature of a wall of the measuring chamber are made to suit the properties of the liquid in such a way that, a radius of the chamber is commensurate with a curved portion of a meniscue of the liquid to provide for a continuous curvature of meniscus across a diameter of the chamber, so that even in a tilted position of the measuring chamber ( 2 ), a surface of the liquid forms a meniscus ( 14 ) which forms a reflection portion directed toward the ultrasonic transceiver ( 6 ).