Door construction

Claim 1

IN A HOLLOW MEMBER, A FLOOR, VERTICALLY DISPOSED SIDE WALLS AND A TOP, THERE BEING DOORWAY OPENINGS IN SAID SIDE WALLS, VERTICALLY DISPOSED POSTS ON OPPOSITE SIDES OF SAID OPENINGS, HORIZONTALLY DISPOSED CROSSPIECES ABOVE SAID POSTS, FIRST AND SECOND PAIRS OF TRACKS IN SAID HOLLOW MEMBER, EACH OF SAID TRACKS INCLUDING HORIZONTALLY DISPOSED UPPER SECTIONS, INTERMEDIATE ROUNDED SECTIONS AND VERTICALLY DISPOSED LOWER SECTIONS, THE UPPER HORIZONTALLY DISPOSED SECTIONS OF SAID FIRST TRACKS BEING ARRANGED ABOVE THE UPPER SECTIONS OF SAID SECOND TRACKS, ANCHOR MEMBERS AFFIXED TO ONE OF SAID CROSSPIECES, THE UPPER HORIZONTALLY DISPOSED SECTIONS OF SAID FIRST TRACKS BEING SLIDABLY CONNECTED TO SAID ANCHOR MEMBERS, A SUPPORT MEMBER INCLUDING A HORIZONTALLY DISPOSED TOP PORTION, HANGERS CONNECTING THE TOP PORTION OF SAID SUPPORT MEMBER TO THE TOP OF SAID HOLLOW MEMBER, SAID SUPPORT MEMBER FURTHER INCLUDING VERTICALLY DISPOSED DEPENDING END PORTIONS AND HORIZONTALLY DISPOSED BOTTOM PORTIONS, CLIPS DEPENDING FROM THE TOP PORTION OF SAID SUPPORT MEMBER FOR SLIDABLY SUPPORTING THE UPPER SECTIONS OF SAID FIRST TRACKS, BRACKETS ON THE UPPER INNER ENDS OF THE BOTTOM PORTIONS OF SAID SUPPORT MEMBER FOR SLIDABLY SUPPORTING THE UPPER SECTION OF THE SECOND TRACKS, ADJUSTABLE DOORS MOVABLY CONNECTED TO EACH PAIR OF TRACKS, EACH OF SAID DOORS INCLUDING A PLURALITY OF SECTIONS HINGEDLY CONNECTED TOGETHER, ROLLERS CONNECTED TO SAID DOORS AND ENGAGING SAID TRACKS, CABLES AND WINCHES FOR RAISING AND LOWERING THE DOORS ALONG THE TRACKS, U-SHAPED BASE MEMBERS SECURED TO THE LOWER INNER PORTIONS OF SAID POSTS, PINS SUPPORTED BY SAID BASE MEMBERS, AND APERTURED LUGS ON THE LOWER END PORTIONS OF THE TRACKS SLIDABLY ENGAGING SAID PINS.