Device for producing cold at low temperatures and cold-gas refrigerator particularly suitable for use in such a device

Claim 1

AN APPARATUS FOR PRODUCING COLD AT LOW TEMPERATURES COMPRISING AT LEAST ONE COLD-GAS REFRIGERATOR HAVING AT LEAST ONE SPACE OF VARIABLE VOLUME AND LOWER MEAN TEMPERATURE, A SEPARATE SPACE OF VARIABLE VOLUME AND HIGHER MEAN TEMPERATURE THAN SAID ONE SPACE AND COMMUNICATING WITH THE LATTER, SAID COMMUNICATING MEANS INCLUDING AT LEAST ONE REGENERATOR THEREIN, A WORKING MEDIUM ADAPTED TO FLOW THROUGH SAID REGENERATOR AND SAID SPACES, AN OUTLET DUCT CONNECTED TO THE SPACE HAVING THE LOWER MEAN TEMPERATURE FOR CONDUCTING PART OF SAID WORKING MEDIUM OUT OF SAID SPACE, SAID OUTLET DUCT HAVING A MEMBER WHICH CONDUCTS SOME OF SAID WORKING MEDIUM OUT OF SAID WORKING SPACE WHEN THE PRESSURE THEREIN EXCEEDS THE MINIMUM PRESSURE, A HEAT EXCHANGER CONNECTED TO SAID OUTLET DUCT, A FURTHER DUCT HAVING AN EXPANSION DEVICE THEREIN CONNECTED TO SAID HEAT EXCHANGER, A STORAGE RECEPTACLE HAVING SAID EXPANSION DEVICE THEREIN, SAID WORKING MEDIUM FORMING AN EXPANDED MEDIUM IN SAID EXPANSION DEVICE, SAID EXPANDED MEDIUM AFTER EXPANSION SUPPLYING COLD, AND A RETURN DUCT FOR SAID EXPANDED MEDIUM CONNECTED TO SAID STORAGE RECEPTACLE AND WHICH COMMUNICATES THROUGH SAID HEAT EXCHANGER WITH SAID SPACE OF LOWER MEAN TEMPERATURE AND INCLUDES A MEMBER WHICH PERMITS SAID EXPANDED MEDIUM TO ENTER SAID SPACE OF LOWER MEAN TEMPERATURE AT A PREVAILING PRESSURE BETWEEN THE MINIMUM PRESSURE AND THE PRESSURE AT SAID OUTLET DUCT, SAID EXPANDED MEDIUM IN SAID HEAT EXCHANGER BEING IN THERMAL CONTACT WITH THE COUNTER CURRENT WORKING MEDIUM.

Claim 2

AN APPARATUS FOR PRODUCING COLD AT LOW TEMPERATURES COMPRISING AT LEAST ONE COLD-GAS REFRIGERATOR HAVING AT LEAST ONE SPACE OF VARIABLE VOLUME AND LOWER MEAN TEMPERATURE, A SEPARATE SPACE OF VARIABLE VOLUME AND HIGHER MEAN TEMPERATURE THAN SAID ONE SPACE AND COMMUNICATING WITH THE LATTER, SAID COMMUNICATING MEANS INCLUDING AT LEAST ONE REGENERATOR THEREIN, A WORKING MEDIUM ADAPTED TO FLOW THROUGH SAID REGENERATOR AND SAID SPACES, AN OUTLET DUCT CONNECTED TO THE SPACE HAVING THE LOWER MEAN TEMPERATURE FOR CONDUCTING PART OF SAID WORKING MEDIUM OUT OF SAID SPACE, SAID OUTLET DUCT HAVING A MEMBER WHICH CONDUCTS SOME OF SAID WORKING MEDIUM OUT OF SAID WORKING SPACE WHEN THE PRESSURE THEREIN EXCEEDS THE MINIMUM PRESSURE, A HEAT EXCHANGER CONNECTED TO SAID OUTLET DUCT, A FURTHER DUCT HAVING AN EXPANSION DEVICE THEREIN CONNECTED TO SAID HEAT EXCHANGER, A STORAGE RECEPTACLE HAVING SAID EXPANSION DEVICE THEREIN, SAID WORKING MEDIUM FORMING AN EXPANDED MEDIUM IN SAID EXPANSION DEVICE, SAID EXPANDED MEDIUM AFTER EXPANSION SUPPLYING COLD, AND A RETURN DUCT FOR SAID EXPANDED MEDIUM CONNECTED TO SAID STORAGE RECEPTACLE AND WHICH COMMUNICATES THROUGH SAID HEAT EXCHANGER WITH SAID SPACE OF LOWER MEAN TEMPERATURE AND INCLUDES A MEMBER WHICH PERMITS SAID EXPANDED MEDIUM TO ENTER SAID SPACE OF LOWER MEAN TEMPERATURE AT A PREVAILING PRESSURE BETWEEN THE MINIMUM PRESSURE AND THE PRESSURE AT SAID OUTLET DUCT, SAID EXPANDED MEDIUM IN SAID HEAT EXCHANGER BEING IN THERMAL CONTACT WITH THE COUNTER CURRENT WORKING MEDIUM.