Abstract: An overhead swinging door is swingably mounted on two side supports slidable in two vertical guides and each connected to a counterweight by a cable re-directed over an upper pulley. On at least one of the door sides, the counterweight is also connected to the respective side support by a chain which forms an endless ring with the cable and is re-directed over a lower wheel driven by a motor and reducing gear unit which is preferably located within the side upright of the door frame.