a trolley conductor bridging means in an electrically powered trolley vehicle transportation system where said trolleys run by contact with a solid conductor and where said conductors are interrupted to provide a door clearance opening is disclosed wherein said means when closed provides for continuous electrical power and mechanical indistinguishable connection across said interruption and wherein said means is opened and closed automatically by the downward and upward force of the transverse moving door . the downward and upward force of said door is translated to the bridge by a cam follower motion of the door edge with the bridge cams and said door is kept electrically non - conductive by insulation of the bridge cam surfaces .