Abstract: A sliding door arrangement which provides lateral support for the free edge or bottom nose corner of a door comprises a retractable member which is raised through an aperture in the floor or doorway threshold to interlockingly engage said edge of the door in the closed position. When the door is opened the engaging member is automatically retracted to lie flush with the floor surface. The member is carried by a rocking lever under the floor which is linked to another counter-balanced lever nearer the door frame which also has a raised protrusion which is abutted by a cam on the door as it reaches the closed position.

Abstract: A plug door for a vehicle, such as a railway carriage, is carried and driven by a swinging lever which has a sliding fulcrum mechanism the effect of which is to flatten the arc through which the door is carried. The edge of the door which trails in an opening movement is guided either by means of a relatively long pivot arm or by a curved or straight track. The alternative guide means give different trajectories to the leading edge of the door, the long pivot arm guide keeps the door closest to the side of the vehicle during opening. A duplicate swinging lever with sliding fulcrum mechanism as a guide for the trailing edge will move the door parallel to the side of the vehicle and the sliding fulcrums will substantially reduce the outward excursion. By mounting the driving swinging lever over-center, i.e. closer to the trailing edge of the door the plug action is provided for so that a closed door may be flush with the vehicle skin.