Patent ID: 8947103
Filing Date: 2015-02-03
Classification: H03K

Abstract:
1. An inductive proximity switch for detecting a presence of an object in a monitored area, the inductive proximity switch comprising: a coil; a pulse source configured to supply said coil with transmitting current pulses at a period larger than a duration of said transmitting current pulses; and a processing circuit configured to generate an output signal based on received voltages varying in dependence on a change of position of the object, said received voltages being induced in said coil after a duration of a transmitting current pulse by the decaying current which previously flows in the object due to the voltage induced therein by said coil, wherein said received voltages induced in said coil are temporarily shifted from said transmitting current pulses; a suppression circuit configured to fully suppress a signal duration lower than a predetermined perturbation time in said output signal such that a minimum time interval between two variations of said output signal does not go below said perturbation time; said processing circuit being configured to generate an intermediate signal from said voltages induced in said coil, said intermediate signal comprising two signal states, and to feed said intermediate signal to said suppression circuit to generate said output signal; and said suppression circuit comprising at least one delay circuit for delaying the output signal by a duration of said perturbation time for each of said signal states with respect to said intermediate signal.