Bi-parting shutter system

A bi-parting shutter system comprising two shutters slidably arranged within an enclosure for displacement between a closed position in which the shutters cooperate to cover an opening in the enclosure and an open position in which the shutters are disposed within the enclosure outward of the opening, the two shutters being connected to each other by linkage means whereby movement of a first shutter causes a corresponding displacement of the second shutter;

• characterized in that said shutters are connected in a manner as to preclude movement of a single shutter independently of the other shutter and wherein the corresponding displacement of said second shutter is equal to the movement of said first shutter and in an opposite direction whereby said shutters simultaneously close toward each other and open outwardly away from each other, said linkage means comprising a track, a single flexible endless belt arranged in said track, guide means mounted at each end of said track, said belt being mounted in a closed loop configuration about said guide means and providing two mutually opposed belt runs simultaneously movable in opposed directions, said track being disposed adjacent to said slidably displaceable shutters with said runs extending longitudinally in the direction of movement of said shutters and defining, relative to said shutters, a proximal belt run and a distal belt run, said first shutter being attached to said proximal run of said belt and bracket member attaching said second shutter to said distal run of said belt, said bracket member having a hollow cross section with said proximal run of said belt freely movable therethrough the cross-section of said bracket member being such as to fit closely yet slidably within said track.