Device for determining the filling level of a filling material in a container

#The present invention relates to a device for determining the filling level of a filling material in a container.

#The device has a signal-generating unit, which generates electromagnetic measuring signals, a transceiver unit, which emits the measuring signals via an antenna in the direction of the surface of the filling material and which receives the echo signals reflected at the surface of the filling material, the antenna comprising a waveguide which widens in the direction of emission into a cavity of a defined shape, and an evaluation unit which determines the filling level in the container from the propagation time of the measuring signals.

#Devices of the above-named type preferably operate in the microwave region and are generally known under the name of microwave filling level measuring instruments. However, it is also possible in principle to operate the device according to the present invention with the aid of ultrasonic measuring signals.

#FIG. 1 shows a schematic of a first embodiment of the device according to the invention.

#FIG. 2 shows a schematic of a second embodiment of the device according to the invention,

#FIG. 3 shows a schematic of a third embodiment of the device according to the invention, and

#DESCRIPTION OF THE PREFERRED EMBODIMENTS

#A schematic of a first embodiment of the device according to the invention is shown in FIG. 1. The antenna 1 consists of a waveguide 3, which is adjoined in the direction of emission of the electromagnetic measuring signals by a widened cavity 4. Moreover, in the case illustrated the antenna 1 is a horn antenna with a circular cross section.

#The electromagnetic measuring signals are coupled into the antenna 1 laterally via the transceiver unit 2 or coupled out laterally from the antenna 1. The signal-generating unit and the control/evaluation unit are illustrated as a combined unit 12 in FIGS. 3 and 4.