US Patent 8443549 Sliding door with large opening

A door assembly includes a track, a track header, a fixed door panel, at least two sliding door panels, a pivot mechanism, and a lock arrangement. The sliding door panels are slidably movable on the track between (1) a closed position wherein the sliding door panels are extended across the track, and (2) an open position wherein the sliding door panels are constructed and arranged to be in a compact, overlapping relationship with each other and the fixed door panel. The pivot mechanism is constructed and arranged to enable pivotal movement of the track with fixed door panel and the two sliding door panels mounted thereon about a pivot axis from a normal configuration to a breakaway configuration. The lock arrangement is constructed and arranged to releasably lock the track with respect to the track header to prevent pivotal movement of the track away from the normal configuration.