Patent ID: 7861587

Claim:
A device for measuring the level of a liquid according to the ultrasound-echo principle in a container with an ultrasonic transducer ( 2 ), wherein the ultrasonic transducer ( 2 ) is disposed at a distance from a reflecting surface disposed in the bottom region and is designed for irradiation to the liquid surface and to the lower reflecting surface ( 6 ), wherein a sunken portion ( 21 ) in the bottom is disposed beneath the ultrasonic transducer ( 2 ) for a reference measurement between the transducer ( 2 ) and the bottom of the sunken portion ( 21 ), and the device is designed as a flange ( 20 ) with a sealing ring ( 22 ) for mounting in an opening at the underside of the container; and wherein the sunken portion ( 21 ) is designed channel-like allowing through-flow of the liquid.