JPS6418769A - Track circuit receiver for automatically compensating for received input voltage - Google Patents

Abstract

PURPOSE:To enable a train to be stably detected by obtaining a time change amount of received input voltage of a track circuit to judge the entrance of train when said change amount exceeds a certain amount and automatically adjust the train detecting voltage for compensating for the received voltage when the change amount is less than a certain amount. CONSTITUTION:A track circuit sends a signal from a transmitter 1 through rails to the input of a receiver 2 and detects a train to operate a track relay 3 when the train enters the corresponding division and shortcircuits the rails to lessen the received input. The receiver 2 is provided with an input filter unit 7, wave detector 8, level detecting unit 9 and power amplifying unit 10. Then, the receiver, 2 is further provided with a received input voltage change detecting unit 5 and a train detecting level setting unit 6. Said detecting unit 5 monitors the time change amount of input voltage to judge the entrance of train if the change amount is large, while judging the voltage variation if the change amount is small and sending the detecting level changed smaller by said setting unit 6 to the input of level detecting unit 9.