Cryogenic refrigeration method and device

A cryogenic refrigeration installation comprising:

• an enclosure (2) delimiting a vacuum-sealed volume closed by a cover (3), the enclosure (2) accommodating at least two thermally conductive trays (4, 5, 6, 7) that are distributed along a distribution direction in the enclosure (2) and form thermal stages;
• a system for cooling to a cryogenic temperature, which is configured to cool at least some of the trays (4, 5, 6, 7) and/or support plate(s) (24, 25, 26, 27) mounted on the tray(s), the cooling system being configured to supply a flow of cryogenic fluid which has been expanded and/or stored, wherein at least one of the trays (4, 5, 6, 7) is connected to a heat shield (14, 15, 16, 17) forming a thermal insulation volume;
• and
• a set of support plate(s) (24, 25, 26, 27) that is/are mounted on the trays (4, 5, 6, 7) and form(s) a support for a set of cable(s) (30) and/or samples to be cooled,
• wherein the system for cooling to a cryogenic temperature is configured to cool at least some of the trays (4, 5, 6, 7) and/or support plate(s) (24, 25, 26, 27),
• wherein the system for cooling to a cryogenic temperature comprises a refrigerator (70) comprising a cryogenic cycle fluid and a cooling circuit (20) for putting the cycle fluid in circulation and into a heat-exchange relationship at at least a part of the periphery of at least one support plate (24, 25, 26, 27).

A cryogenic refrigeration installation comprising:

• an enclosure (2) delimiting a vacuum-sealed volume closed by a cover (3), the enclosure (2) accommodating at least two thermally conductive trays (4, 5, 6, 7) that are distributed along a distribution direction in the enclosure (2) and form thermal stages,
• the installation (1) comprising a system for cooling to a cryogenic temperature, which is configured to cool at least some of the trays (4, 5, 6, 7) and/or support plate(s) (24, 25, 26, 27) mounted on the tray(s), the cooling system being configured to supply a flow of cryogenic fluid which has been expanded and/or stored, wherein at least one of the trays (4, 5, 6) is connected to a heat shield (14, 15, 16) forming a thermal insulation volume, the system for cooling to a cryogenic temperature comprising a refrigerator (70) having a refrigeration cycle for a cycle fluid, said refrigerator (70) comprising a cycle circuit (8) containing:
• a cycle fluid comprising helium, the cycle circuit (8) being configured to subject the cycle fluid to a thermodynamic cycle that brings the cycle fluid to a given cold temperature at at least one cold end of the cycle circuit (8), the cycle circuit being further configured to put a flow of cycle fluid at the cold end into a heat-exchange relationship with at least some of the trays (4, 5, 6) and/or plates (24, 25, 26),
• the cycle circuit (8) comprising a compression mechanism (9) configured to compress the cycle fluid,
• at least one cooling member (11, 12, 13, 114) configured to cool the cycle fluid,
• an expansion mechanism (10, 115) configured to expand the cycle fluid and
• at least one reheating member (114, 13, 12, 11) configured to reheat the expanded cycle fluid,
• the cycle circuit (8) further comprising a first vessel (117) configured to store a reserve of liquefied cycle fluid,
• the cycle circuit (8) further comprising, downstream of the heat-exchange relationship with at least some of the trays (4, 5, 6) and/or plates (24, 25, 26), a bypass pipe (18) configured to divert at least a part of the flow of cycle fluid to the first storage vessel (117), the bypass pipe (18) comprising a bypass expansion member (119) configured to expand a flow of cycle gas that is configured to expand the cycle gas before supplying the first storage vessel (117),
• the cycle circuit (8) comprises, upstream of the heat-exchange relationship with at least some of the trays (4, 5, 6) and/or plates (24, 25, 26), a portion in a heat-exchange relationship with the liquefied cycle fluid contained in the first storage vessel (117).