Description
Class B61L : GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
Subclass 1/12: Devices along the route controlled by interaction with the vehicle or vehicle train (detonators B61L 5/2 ; operation of points or signals by passage of the vehicle B61L 11/00, B61L 13/00 ; operation of gates, or gates and signals, by approaching vehicle B61L 29/18 ) Electric devices associated with overhead trolley wires