Air distribution system for combination freezer-refrigerator

Claim 1

AN AIR DISTRIBUTION SYSTEM FOR A COMBINATION FREEZERREFRIGERATOR UNIT HAVING A REFRIGERATOR SECTION LOCATED BELOW AND SEPARATED BY A PARTITION FROM A FREEZER SECTION TO EACH OF WHICH SECTIONS AIR COOLED TO BELOW FREEZING TEMPERATURE BY A REFRIGERATION SYSTEM IS CIRCULATED BY A FAN LOCATED IN SAID PARTITION, SAID AIR DISTRIBUTION SYSTEM COMPRISING AN INNER DUCT EXTENDING UPWARDLY ALONG THE REAR WALL OF SAID FREEZER SECTION FROM THE DISCHARGE SIDE OF SAID FAN AND TERMINATING IN A DISCHARGE OPENING IN THE TOP REAR WALL OF SAID FREEZER SECTION, AN OUTER DUCT FORMED INTEGRALLY ON THE REAR WALL OF SAID INNER DUCT EXTENDING DOWNWARDLY BETWEEN SAID INNER DUCT AND THE OUTER REAR WALL OF SAID UNIT AND TERMINATING AT A DISCHARGE OPENING NEAR THE TOP REAR WALL OF SAID REFRIGERATOR SECTION, THE UPPER END OF SAID OUTER DUCT COMMUNICATING WITH THE UPPER END OF SAID INNER DUCT THROUGH A PORT OF FIXED IN THE COMMON WALL BETWEEN SAID DUCT TO AND RESTRICTING THE FLOW OF AIR FROM SAID INNER DUCT TO SAID OUTER DUCT, A VARIABLE POSITION DAMPER IN THE LOWER END OF SAID OUTER DUCT CONTROLLING THE FLOW OF AIR FROM SAID OUTER DUCT THROUGH THE DISCHARGE OPENING INTO SAID REFRIGERATOR SECTION, FIRST TEMPERATURE RESPONSIVE MEANS IN SAID REFRIGERATOR SECTION CONTROLLING THE POSITION OF SAID DAMPER, AND SECOND TEMPERATURE RESPONSIVE MEANS FOR SAID FREEZER SECTION CONTROLLING THE OPERATION OF THE REFRIGERATION SYSTEM AND SAID FAN, THE RESTRICTION OF SAID PORT REDUCING THE VOLUME OF AIR ADMITTED TO SAID OUTER DUCT WHEN SAID DAMPER IS IN ITS FULLLY OPEN POSITION TO LESS THAN TWENTY PERCENT OF THE TOTAL VOLUME OF AIR DELIVERED THROUGH SAID INNER DUCT BY SAID FAN.