Hot gas defrost refrigerating system and valve means therefor

Claim 1

A VALVE FOR MODIFYING THE FLOW OF REFRIGERANT IN A REFRIGERATING SYSTEM INCLUDING A COMPRESSOR, A CONDENSER, A RESTRICTOR, AN EVAPORATOR AND A SUCTION LINE NORMALLY CONNECTED IN CLOSED, SERIES FLOW RELATIONSHIP IN ORDER TO INTRODUCE COMPRESSED REFRIGERANT FROM THE COMPRESSOR DIRECTLY INTO THE EVAPORATOR AND AUTOMATICALLY RESTRICT THE FLOW OF REFRIGERANT THROUGH THE SUCTION LINE, SAID VALVE COMPRISING: (A) A CYLINDRICAL VALVE BODY, SAID BODY INCLUDING, (B) AN INLET CHAMBER HAVING AN INLET FOR CONNECTION TO THE COMPRESSOR DISCHARGE, (C) AN OUTLET CHAMBER HAVING AN OUTLET FOR CONNECTION TO THE INLET END OF THE EVAPORATOR, (D) A FIRST SUCTION LINE CONNECTION TO SAID EVAPORATOR AND A SECOND SUCTION LINE CONNECTION TO SAID COMPRESSOR INTAKE, SAID SUCTION LINE CONNECTIONS BEING SPACED FROM SAID OUTLET, (E) NORMALLY CLOSED VALVE MEANS BETWEEN SAID INLET AND OUTLET CHAMBERS AND MEANS FOR OPENING SAID VALVE MEANS, AND (F) A PISTON IN SAID VALVE BODY FORMING ONE WALL OF SAID OUTLET CHAMBER AND NORMALLY POSITIONED WITHIN SAID VALVE BODY BETWEEN SAID OUTLET AND SAID SUCTION LINE CONNECTIONS AND MOVABLE TO A SECOND POSITION BETWEEN SAID SUCTION LINE CONNECTIONS BY AN INCREASE IN PRESSURE IN SAID OUTLET CHAMBER WHEN SAID VALVE MEANS IS OPEN, SAID PISTON INCLUDING MEANS DEFINING A RESTRICTED COMMUNICATION BETWEEN SAID SUCTION LINE CONNECTIONS WHEN SAID PISTON IS IN SAID SECOND POSITION.