High speed folding door

Abstract

A multi-section folding door includes first and second sets of vertically aligned panels with the panels in each set coupled together in an edge overlapping manner. Each of the panels is suspended from a support bracket attached to the panel's upper edge, with each of the brackets coupled to and suspended from a track by means of a respective trolley. The trolleys permit the first and second sets of panels to be displaced toward or away from each other in closing or opening the folding door relative to an opening in a wall. An endless chain/sprocket arrangement driven by an electric motor allows the multi-panel folding door to be opened and closed very rapidly. A thickened upper edge of each panel is inserted in a lower slot of a respective support bracket along the length thereof to facilitate assembly and installation of the door as well as replacement of a damaged or worn panel. One or more breakaway straps couple adjacent panels in each set of panels to facilitate re-connecting adjacent panels as well as to reduce the possibility of damage to the trolleys and support track upon impact of a moving vehicle with a door panel. Each of the trolleys includes a plurality of rollers engaging the I-beam shaped support track in a self-aligning arrangement which provides continued rolling displacement of the trolleys along the track following vehicular impact with and displacement of its associated suspended panel.