Power operated bi-fold strip curtain door assembly

A strip curtain bi-fold door assembly adapted for use in a door space defined by an overhead track, a floor and a pair of spaced apart uprights, said door assembly comprising:

• at least a pair of laterally positioned inboard and outboard door means having opposed adjacent ends and free ends for closing at least a part of the door space, each said door means including support means for suspending a group of elongated flexible strip curtains in overlapping relation;
• first hinge means for connecting the opposed adjacent ends of said door means;
• second hinge means adapted to connect the free end of the outboard door means to one of the uprights;
• carriage means adapted to guidingly engage the track for travel therealong;
• said carriage means including pivot pin means adapted for suspending the inboard door means adjacent its free end for pivotal movement during travel of said carriage means;
• and
• fluid actuator means adapted to be interconnected between one of said door means and said one upright and effective when actuated to move said door means and their associated group of strip curtains between a folded position adjacent said one upright and an extended side-by-side position across the door space;
• said fluid actuator means being in the form of a piston and cylinder having one end pivotally connected to said one upright and an extensible and retractable piston rod extending from said cylinder other end with the rod pivotally connected to said outboard door means;
• said outboard and inboard door means having terminal interior strip curtains at their opposed adjacent ends, one of said door means having a terminal exterior strip curtain vertical border portion extending laterally a predetermined distance beyond the associated opposed adjacent end of said one door means;
• means reinforcing the upper horizontal edge of said terminal exterior strip curtain such that its border portion is maintained in the plane of an associated group of exterior strip curtains overlapping said interior strip curtains, whereby upon said door means being extended said terminal exterior strip curtain border portion overlapping the next adjacent terminal interior strip curtain of the other door means such that a lap seal is provided at the juncture of said outboard and inboard groups of curtain strips;
• and
• said door means in their folded position having a V-shaped configuration with first interior surface of said door means facing inwardly in opposed relation;
• and second exterior surfaces of said door means facing outwardly;
• the axis of said fluid actuator means disposed substantially normal to said outboard section exterior surface in its folded position, such that during the initial extension of said piston rod, the mechanical advantage of said actuator means in transmitting force from said piston rod to said outboard section is at a maximum.