Multi-zone refrigeration system and apparatus

Claim 1

A REFRIGERATION SYSTEM COMPRISING: (A) A COMPRESSOR OPERATIVELY CONNECTED TO A SOURCE OF MOTIVE POWER, (B) A CONDENSER RECEIVING GASEOUS REFRIGERANT FROM THE COMPRESSOR TO CONDENSE THE SAME, (C) A FIRST EVAPORATOR RECEIVING LIQUID REFRIGERANT FROM THE CONDENSER, (D) A SECOND EVAPORATOR RECEIVING LIQUID REFRIGERANT FROM THE CONDENSER AND OPERATING AT A TEMPERATURE SUBSTANTIALLY HIGHER THAN THE OPERATING TEMPERATURE OF THE FIRST EVAPORATOR, (E) EXPANSION MEANS DISPOSED BETWEEN THE CONDENSER AND EACH OF THE EVAPORATORS TO EXPAND THE LIQUID REFRIGERANT SELECTIVELY RESPONSIVE TO THE OPERATING TEMPERATURE OF THE EVAPORATORS, (F) THE COMPRESSOR HAVING A FIRST STAGE AND A SECOND STAGE, (G) THE FIRST STAGE OF THE COMPRESSOR CONNECTED TO DRAW REFRIGERANT FROM THE FIRST EVAPORATOR AND COMPRESS THE SAME, (H) THE SECOND STAGE OF THE COMPRESSOR CONNECTED TO DRAW REFRIGERANT FROM BOTH THE FIRST STAGE AND THE SECOND EVAPORATOR IN A COMBINED FLOW FOR COMPRESSING THE REFRIGERANT PRIOR TO DISCHARGE THREOF INTO THE CONDENSER, (I) A FIRST UNLOADER MEANS OPERATIVELY CONNECTED WITH THE FIRST STAGE OF THE COMPRESSOR, (J) A SECOND UNLOADER MEANS OPERATIVELY CONNECTED WITH THE SECOND STAGE OF THE COMPRESSOR, AND (K) A CONTROL MEANS TO SENSE THE OPERATING TEMPERATURE CONDITIONS OF THE REFRIGERATION SYSTEM AND TO SELECTIVELY OPERATE THE FIRST UNLOADER MEANS AND THE SECOND UNLOADER MEANS TO MAINTAIN THE VOLUMETRIC DISPLACEMENT OF THE COMPRESSOR RESPONSIVE TO THE OPERATING LOAD CONDITIONS.