Current Collector

Electric current collectors are used for trolleybuses, trams, electric locomotives or EMUs to lead electrical power from overhead lines or electrical third rails to the electrical equipment of the vehicles.
Typically, they have one or more spring loaded arms that permits the working engagement with the rail or overhead wire and a collector or contact shoe in running engagement with the wire or rail. The collector arms push the contact shoe against the contact wire or rail. As the vehicle moves, the contact shoe slides along the wire or rail to draw the electricity needed to run the vehicles motor.