Bi-fold door with self-contained motor

Claim 1

A CANOPY-TYPE CLOSURE STRUCTURE FOR AN OPENING IN AN UPRIGHT WALL, COMPRISING: AN UPPER PANEL AND PIVOT MEANS SUPPORTING SAID UPPER PANEL AT POINTS SPACED FROM THE UPPER AND LOWER EDGES THEREOF FOR PIVOTAL MOVEMENT ABOUT A PIVOT AXIS SUBSTANTIALLY PARALLEL WITH SAID EDGES; A LOWER PANEL AND MEANS HINGEDLY CONNECTING THE UPPER EDGE THEREOF TO THE LOWER EDGE OF SAID UPPER PANEL; A PAIR OF SUBSTANTIALLY PARALLEL AND UPRIGHT GUIDE MEMBERS MOUNTED ON THE WALL ADJACENT RESPECTIVE SIDES OF SAID OPENING, SAID GUIDE MEMBERS HAVING UPPER AND LOWER PORTIONS DISPOSED AT SLIGHT ANGLES TO EACH OTHER, AND SAID GUIDE MEMBERS EXTENDING FROM NEAR THE LOWER END OF SAID OPENING TO POINTS ADJACENT SAID PIVOT AXIS; GUIDE MEANS MOUNTED ON SAID LOWER PANEL BETWEEN THE UPPER AND LOWER EDGES THEREOF AND ENGAGED WITH SAID GUIDE MEMBERS FOR GUIDING SAID LOWER PANEL AS IT IS MOVED VERTICALLY ALONG THE SAID GUIDE MEMBERS; A SHAFT ROTATABLY MOUNTED ON SAID UPPER PANEL NEAR THE UPPER EDGE THEREOF AND ABOVE SAID PIVOT AXIS; AN ELONGATED FLEXIBLE ELEMENT EXTENDING AND CONNECTED BETWEEN SAID SHAFT AND THE LOWER PORTION OF SAID LOWER PANEL; AN ELECTRIC MOTOR MOUNTED ON SAID UPPER PANEL ABOVE SAID PIVOT AXIS; MEANS DRIVINGLY CONNECTING SAID MOTOR TO SAID SHAFT, SO THAT OPERATION OF SAID MOTOR EFFECTS A ROTATION OF SAID SHAFT AND A WINDING OR UNWINDING OF SAID ELEMENT WITH RESPECT TO SAID SHAFT, WHEREBY A RAISING OR LOWERING OF SAID PANELS IS EFFECTED; AND THE LOCATION OF SAID SHAFT AND MOTOR BEING SUCH THAT THEIR WEIGHT TENDS, WHEN SAID UPPER PANEL IS MOVED AROUND SAID PIVOT AXIS, TO COUNTERBALANCE THE WEIGHT OF THE LOWER PANEL AS IT IS MOVED VERTICALLY.