Cryogenic refrigeration method and device

A cryogenic refrigeration device comprising a first refrigerator with a refrigeration cycle for a cycle fluid and at least one cold source, the first refrigerator comprising, in series in a cycle circuit and connected by a set of pipes and a set of valves:

• a compression mechanism for the cycle fluid,
• a first cooling portion for the cycle fluid,
• a first expansion mechanism for the cycle fluid,
• a heating portion for the cycle fluid,
• a first refrigeration portion configured to allow the cooling of a first user, and comprising a first heat exchange system configured to make the cycle fluid exchange heat with the cold source,
• a second heat exchange system configured to make the cycle fluid exchange heat with the cold source,
• a refrigeration assembly configured to make the first user exchange heat with the cycle fluid,
• wherein the set of pipes and the set of valves being configured to switch the device between:
• a first operating configuration, in which at least some of the cycle fluid is directed to the first heat exchange system, then from the first heat exchange system to the refrigeration assembly, and then away from the first refrigeration portion to the cycle circuit;
• a second operating configuration, in which at least some of the cycle fluid is directed to the first heat exchange system, then from the first heat exchange system to the refrigeration assembly, then from the refrigeration assembly to the second heat exchange system, and then from the second heat exchange system to the refrigeration assembly.