Fill-level measuring device

Abstract

The present invention relates to a fill-level measuring device for measuring the fill level of a filling material in a tank (1) capacitively and / or according to the propagation time principle, comprising a coaxial measuring probe, the inner conductor (3) of which is galvanically isolated from the shield conductor (5) of said coaxial measuring probe and the shield conductor (5) of which is electrically at a reference potential, having a fastening device (7) electrically at a reference potential for fastening the measuring device to a tank opening (11) equipped with a counterpart (9) that corresponds to the fastening device (7), an annular disk (13) that is made of an electrically conducting material and that is clamped between the fastening device (7) and the counterpart (9) during measuring operation, an inner conductor (3) that is completely surrounded by an insulating layer (15); and that is fed through the annular disk (13) into the tank (1) during measuring operation, an insulating body (17) that is connected to the insulating layer (15), coaxially surrounds the inner conductor (3), and comprises an annular disk-shaped section (19) that is clamped between the fastening device (7) and the annular disk (13), a shield conductor (5) that coaxially surrounds the inner conductor (3) and is connected to the annular disk (13) mechanically and in an electrically conducting manner, and at least one electrical contact element (23), which is fixed on a spring element (25) in the annular disk (13) outside an area of the annular disk covered by the insulating body (17) and by which the shield conductor (5) is connected to the fastening device (7) through the contact element (23) and the annular disk (13) in an electrically conducting manner.

Description

technical field [0001] The invention relates to a filling level measuring device for measuring the filling level of a filling material in a container, the filling level measuring device having a fully insulated measuring probe inserted into the container. Background technique [0002] Fill level measuring devices of this type are used in a wide range of industrial measuring technology for the level measurement of filling materials in containers. [0003] Two different measuring principles are known which make it possible to measure the filling material in the fill level by means of a measuring probe inserted into the container. [0004] The first measurement principle is based on time-of-flight measurement. In this case, the fill level measuring device generates an electromagnetic signal which is emitted into the container along a measuring probe which is used as a waveguide in this case. A part of these electromagnetic signals is reflected at the filling material surface ...

AI Technical Summary

Problems solved by technology

If this is not given, there is an impedance jump in the region where the electromagnetic signal is coupled into the coaxial probe, which results in a strong input reflection of the electromagnetic signal in this region

This unwanted input reflection results in a significant increase in lost power

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