Signalling locomotive location on railway tracks - is performed by detecting magnetic anomalies around passing vehicle

摘要

A signalling system is used for detecting the prescence of locomotives on railway tracks (1) and indicating that presence at a remote control location. The system utilises magnetic anomaly detector (5) spaced along the track which responds to variation in the ambient magnetic flux caused by the presence of the ferromagnetic bulk of the locomotive. The detectors are recessed into the upper surface of the railway sleepers to present a flush surface to the rail bed.