Three-way valve and system therefor

Claim 1

A REFRIGERATION SYSTEM COMPRISING A COMPRESSOR HAVING A HIGH PRESSURE DISCHARGE LINE AND A SUCTION LINE, A CONDENSER, A RECEIVER, AND A PLURALITY OF PARALLEL CONNECTED CIRCUITS CONNECTED IN SERIES BETWEEN THE COMPRESSOR DISCHARGE AND SUCTION LINES, EACH OF SAID PARALLEL CONNECTED CIRCUIT INCLUDING AN EVAPORATOR DEVICE AND A SEPARATE CONTROL VALVE FOR SELECTIVELY REFRIGERATING OR DEFROSTING SAID EVAPORATOR, EACH OF SAID CONTROL VALVES HAVING A CONNECTION TO THE COMPRESSOR DISCHARGE LINE, A CONNECTION TO THE COMPRESSOR SUCTION LINE AND A CONNECTION TO THE ASSOCIATED EVAPORATOR, AND PERATOR MEANS FOR EACH OF SAID CONTROL VALVES FOR SELECTIVELY COMMUNICATING THE EVAPORATOR TO THE COMPRESSOR SUCTION LINE TO PRODUCE FLOW THERETHROUGH IN ONE DIRECTION FOR REFRIGERATION AND TO THE COMPRESSOR DISCHARGE LINE TO PRODUCE FLOW THERETHRTOUGH IN THE OPPOSITE DIRECTION FOR DEFROSTING, EACH OF SAID CONTROL VALVES INCLUDES A THREE-WAY VALVE HAVING A FIRST CHAMBER PORTION THEREIN CONNECTED TO THE COMPRESSOR DISCHARGE LINE, A SECOND CHAMBER PORTION THEREIN CONNECTED TO THE COMPRESSOR SUCTION LINE, AND A THIRD CHAMBER PORTION CONNECTED TO THE EVAPORATOR, SAID OPERATOR MEANS INCLUDING A VALVE MEMBER MOVABLE IN SAID CHAMBER PORTIONS FOR SELECTIVELY COMMUNICATING SAID THIRD CHAMBER PORTION WITH SAID FIRST AND SECOND CHAMBER PORTIONS.