MODULAR POINT DETECTOR FOR RAILROAD TRACK SWITCH

摘要

A modular sensor apparatus (48,52) for detecting the location of a movable track point includes a primary sensor (132) and a secondary sensor (136) disposed on a sensor mount (128) that is movable with respect to a frame (96) that is mounted on a switch machine. The secondary sensor (136) is offset from the primary sensor (132) in order to permit the secondary sensor (136) to detect the need for imminent readjustment of the track point prior to the time at which the track point becomes maladjusted and in need of immediate readjustment. The sensor mount (128) is threadably adjustable with respect to the frame (96), whereby once the primary sensor (132) has detected the position of the movable track point when it is disposed against a fixed stock rail, the sensor mount (128) can be moved a fixed threshold distance by rotating a thumbwheel (160) a fixed number of turns.