Automatic connection and disconnection of current collectors for trolley

Abstract

Electrically powered trolley vehicles in headings of mines are provided with a current collector pick-up unit having contact-sensing means, current collectors, position sensors and guide wheels. The power supply for the pick-up unit comprises an array of elongated guide rails and at least two conductor bars. The connecting method comprises running the vehicle slowly forwards, by means of its own energy source, in the direction of the elongated conductor bars and vertically raising the pick-up unit by means of an arm mounted on the vehicle so that a contact-sensing frame for sensing contact in a vertical direction is brought into engagement with one or both of the guide rails. During a continued vertical movement, the contact-sensing frame is turned down towards the rest of the pick-up unit and when the contact-sensing frame reaches its lower end limit position, this is indicated by a position sensor. The pick-up unit is then turned in the lateral direction until contact-sensing bars for horizontal sensing are brought into engagement with the nearest guide rail. When the position sensors indicate this, the frame is lowered and the pick-up unit with its current collectors and guide wheels is raised towards the conductor array, whereby the current collectors are brought into contact with the conductor bars and the guide wheels are brought into contact with the guide rails.