Built-in vacuum cleaning system

Claim 1

A SELF-CONTAINED UNITARY NONPORTABLE SUCTION CLEANING SYSTEM FOR USE IN CLEANING SURFACES WITHIN BUILDINGS AND PROVIDED WITH MEANS FIXEDLY ANCHORING THE SAME IMMOVABLY TOT HE BUILDING, SAID SYSTEM INCLUDING AN ARRANGEMENT OF INSTALLED DUCTS IN COMMUNICATION WITH ONE ANOTHER AND HAVING A PLURALITY OF NORMALLY CLOSED INLETS ADAPTED TO BE SELECTIVELY COUPLED TO A FLEXIBLE HOSE HAVING A SUCTION NOZZLE AT ITS INLET END, A UNITARY MAIN CASING HAVING A NORMALLY CLOSED BUT DETACHABLE COVER, INLET CONNECTION MEANS HAVING ONE END OPENING INTO SAID DUCTS AND ITS OTHER END OPENING INTO SAID CASING THROUGH SAID DETACHABLE COVER, A FILTER BAG SUPPORTED WITHIN SAID CASING AND REMOVABLE FOR EMPTYING WHEN SAID COVER IS DETACHED, A PAIR OF EXPOSED STRUCTURALLY-INDEPENDENT TUBULAR BRACKETS, MEANS RIGIDLY SECURING SAID BRACKETS ON THE EXTERIOR WALL OF SAID MAIN CASING IN SPACED-APART RELATION, ONE OF SAID BRACKETS BEING IN COMMUNICATION WITH THE INTERIOR OF SAID MAIN CASING ON THE OPPOSITE SIDE OF SAID FILTER BAG FROM SAID INLET CONNECTION MEANS, A SEPARATE MULTIPLE STAGE MOTOR FAN SUCTION UNIT MOUNTED ON EACH OF SAID BRACKETS, MEANS CONNECTING SAID TUBULAR BRACKETS AND SAID SUCTION UNITS IN SERIES WITH ONE ANOTHER, SAID INLET CONNECTION BEING MOUNTED ON SAID COVER AND OPENING THERETHROUGH TO THE INTERIOR OF SAID CASING, SAID INLET CONNECTION INCLUDING A SHORT LENGTH OF FLEXIBLE HOSE HAVING ONE END ATTACHED TO SAID COVER AND THE OTHER END CONNECTED TO SAID DUCT SYSTEM, AND AT LEAST ONE OF SAID SUCTION FAN UNITS HAVING FINAL FILTER MEANS MOUNTED IN AND READILY DETACHABLE THROUGH AN OPENING IN THE WALL OF ONE OF SAID TUBULAR BRACKETS, AND SAID FINAL FILTER MEANS BEING SUPPORTED ACROSS THE INLET OPENING OF SAID ONE TUBULAR BRACKET AND EFFECTIVE TO COLLECT FOREIGN MATTER CARRIED IN THE SUCTION AIR STREAM ENTERING SAID ONE SUCTION FAN UNIT.