GARAGE DOOR MOVEMENT APPARATUS

摘要

A garage door movement apparatus comprising a garage door vertically movable in tracks to open and close a garage door opening. A jack shaft may be mounted horizontally above the door opening and support a sprocket disposed thereon. A chain may be connected to the door near a bottom thereof and engaged with the sprocket. A spring may be disposed about the jack shaft to provide rotation forces to act against the weight of the door. A track for carrying the garage door is mounted near the garage door opening and has at least a vertical section. In order to convey downward forces on the door from the sprocket, the chain between the sprocket and the door bottom may include a substantially vertical section of a chain guide, which is disposed beneath the sprocket in a direction substantially parallel with the door track.