The present invention is provided with a mechanism for controlling the opening and closing of a door comprising a speed reduction means for reducing a rotational speed. A high speed shaft is connected to the speed reduction means and is connectable to a means for rotating the input shaft, and a low speed output shaft is connected to the speed reduction means. A governor is mounted on the input shaft for limiting the rotational speed thereof, to also regulate the rotational speed of the output shaft. A brake is provided for preventing rotation of the output shaft, and a self-closing mechanism is operatively connected to the door. The self-closing mechanism is adapted for storing energy when the door is opened to an open position, and a connecting means operatively connects the output shaft to the self-closing mechanism. A releasing means is provided for releasing the brake to permit rotation of the output shaft under the urging of the self-closing mechanism whereby the self-closing mechanism releases the energy stored therein so as to close the door to a closed position when the brake is released by the releasing means.