Patent ID: 8493065
Filing Date: 2013-07-23
Classification: G01N

Abstract:
1. A method for detecting electrically conductive particles in a liquid flowing in a pipe segment with a velocity (v), comprising exposing the liquid to a plurality of periodic alternating electromagnetic fields with a transmitter coil arrangement in order to induce a plurality of eddy currents in the particles; detecting a periodic electrical signal according to the plurality of eddy currents with a receiver coil arrangement, such that the periodic electrical signal has a carrier oscillation where at least one of an amplitude and a phase is modulated by the particles when the particles travel into an effective width of the receiver coil arrangement; digitizing the receiver coil signal with an A/D converter stage; producing a useful signal from the digitized receiver coil signal with a signal processing unit; evaluating the useful signal with an evaluation unit in order to detect a passage of electrically conductive particles in the pipe segment; when through monitoring a curve shape of the digitized received coil signal overdriving of the A/D converter stage by the receiver coil signal is ascertained by the signal processing unit and a part of the receiver coil signal is being truncated by the A/D converter stage reconstructing the received coil signal with a mathematical approximation in the digitized receiver coil signal.