System for handling track suspended objects

Claim 1

A DOOR STRUCTURE FREE OF BOTTOM SUPPORT COMPRISING, IN COMBINATION, A FIRST TRACK EXTENDING ALONG A PATH OVERLYING AN AREA TO BE SPANNED BY THE DOOR STRUCTURE AND HAVING A STRAIGHT SECTION EXTENDING BEYOND SAID AREA, A TRACK CURVE HAVING A FIRST BRANCH TRACK SECTION FORMING PART OF SAID STRAIGHT SECTION AND A SECOND BRANCH TRACK CURVINGLY DIVERGING AWAY FROM SAID STRAIGHT SECTION, A THIRD BRANCH TRACK FORMING A CONTINUATION OF THE FIRST TRACK CURVING CONGRUENTLY WITH AND SPACED FROM SAID SECOND BRANCH TRACK, SAID TRACKS HAVING A TUBULAR CROSS-SECTION AND SLOTTED ALONG THEIR UNDERSIDE WHEREBY THE FIRST AND SECOND BRANCH TRACK SLOTS MERGE INTO THE FIRST TRACK SLOT AT A JUNCTION, AND A COMMON SECTION OF TRACK BETWEEN THE MERGING SLOTS TAPERING TO AN END AT SAID JUNCTION, A PLURALITY OF DOOR SECTIONS EACH HAVING A PAIR OF SPACED DOOR HANGERS SUPPORTING THE DOOR SECTION FROM THE TRACK, EACH HANGER INCLUDING A TWO-DIRECTIONAL TROLLEY WITH A PAIR OF RIGIDLY INTERCONNECTED WHEELS DISPOSED WITHIN THE TRACK AND A STIRRUP EXTENDING THROUGH THE SLOT, SAID WHEELS BEING OF A SIZE TO PASS THE JUNCTION AND ENGAGE THE COMMON TRACK SECTION AND A PART OF THE FIRST BRANCH TRACK SECTION WHILE STILL ENGAGING THE FIRST TRACK TO TRAVEL ALONG SAID STRAIGHT SECTION, AND MEANS ASSOCIATED WITH THE TRAILING HANGER OF EACH DOOR SECTION FOR DIVERTING THE WHEELS OF SAID TRAILING HANGER AT SAID JUNCTION ONTO SAID SECOND BRANCH TRACK, WHEREBY EACH DOOR SECTION MAY BE MOVED FROM THE FIRST TRACK TO SAID SECOND AND THIRD BRANCH TRACKS FOR STACKING SIDE-BY-SIDE BY THE LEADING DOOR HANGER TRAVELING PAST THE JUNCTION ONTO THE THIRD BRANCH TRACK AND THE TRAILING HANGER BEING DIVERTED ONTO THE SECOND BRANCH TRACK, EACH OF SAID HANGERS HAVING A PIVOTAL CONNECTION WITH THE ASSOCIATED DOOR SECTION WHEREBY A TROLLEY IS IN LINE WITH A DOOR WHEN THE DOOR IS IN AREA SPANNING POSITION AND EXTENDS TRANVERSE THERETO WHEN THE DOOR SECTIONS ARE STACKED, THE RADIUS OF CURVATURE OF SAID SECOND BRANCH TRACK SECTION BEING SUFFICIENTLY LARGE TO ACCOMMODATE A TROLLEY WITH TWO SPACED RIGIDLY INTERCONNECTED WHEELS AND BEGINNING AT A DISTANCE FROM THE END OF SAID COMMON SECTION APPROXIMATELY EQUAL TO THE LENGTH OF THE TROLLEY TO GRADUALLY INCREASE THE WIDTH OF THE TRACK AND THE SLOT IN ADVANCE OF SAID END WHEREBY THE STIRRUP AND TRAILING TROLLEY WHEEL DO NOT INTERFERE WITH DIVERTING OF THE TROLLEY.