Circuit arrangement for generating axle counter pulses for axle counter systems

摘要

In order to generate axle counter pulses for axle counter systems in railway safety technology, a track device is used with AC-fed transmitting circuits and receiving circuits associated therewith. The useful reception voltage present in each receiving circuit and any steep-edged interference signals present are fed to a converter circuit in order to detect the positive summation envelope curve of the useful reception voltage and of all the steep-edged interference signals. The converter circuit consists of a half-wave rectifier circuit with a first diode (D1) and a capacitor (C1) as charging circuit. Connected in parallel with the capacitor (C1) is a discharge circuit which is briefly switched on at regular intervals as a function of the phase position of the useful reception voltage. A further circuit which permits an electrical simulation of the interference signals on the basis of the evaluation of the steep front edges of the interference signals is connected to this converter circuit. The interference signals which can be represented in this way are fed to a differential amplifier (V2) together with the signals of the summation envelope curve. Said amplifier transmits exclusively interference-free useful signals to an evaluation device (AG) for further processing. IMAGE