Patent 7847539 was granted and assigned to Sick AG on December, 2010 by the United States Patent and Trademark Office.
The invention relates to an inductive proximity sensor with a sensor element which includes a resonant circuit which provides an output signal which depends on the damping by an electrically conductive object. In accordance with the invention, the inductive proximity sensor has a ΣΔ modulator for the evaluation of an output signal of the resonant circuit. The invention furthermore relates to a method for the determination of the presence and/or of the spacing of a metallic object with the help of an inductive proximity sensor.