Dual duct fluid supply system

Claim 1

IN A DUAL DUCT SYSTEM FOR SUPPLYING TEMPERATURE CONDITIONED AIR TO VARIOUS AREAS COMPRISING A CENTRAL UNREGULATED SOURCE OF HEATED AIR UNDER PRESSURE; A CENTRAL UNREGULATED SOURCE OF COOLED AIR UNDER PRESSURE; AND A PLURALITY OF INDEPENDENT OUTLET UNITS, ONE FOR EACH OF THE AREAS, EACH UNIT INCLUDING: A CHAMBER FOR MIXING THE HEATED AIR AND THE COOLED AIR, A FIRST CONDUIT CONNECTING THE MIXING CHAMBER WITH THE HEATED AIR SOURCE, AND A SECOND CONDUIT CONNECTING THE MIXING CHAMBER WITH THE COOLED AIR SOURCE; THE IMPROVEMENT WHICH COMPRISES: IN EACH OF THE CONDUITS, AN ADJUSTABLE VALVE OF KNOWN TYPE WHICH, FOR EACH ADJUSTMENT POSITION, WILL PASS FLUID AT A RATE THAT IS CONSTANT OVER A CORRESPONDING RANGE OF DIFFERENTIAL PRESSURES; AN INDEPENDENT THERMOSTATIC CONTROL DEVICE FOR INDICATING THE VOLUMES OF HEATED AND COOLED AIR THAT ARE TO BE SUPPLIED TO THE AREA; AND MOTOR MEANS RESPONSIVE TO THE THERMOSTATIC CONTROL DEVICE FOR ADJUSTING THE VALVES TO POSITIONS WHICH CORRESPOND TO THE INDICATED VOLUMES OF AIR; WHEREBY EACH AREA IS SUPPLIED WITH THE VOLUMES OF HEATED AND COOLED AIR INDICATED BY ITS CONTROL DEVICE.