| abstract |
A cooling device ( 7 ) for re-liquefying cryogenic gases, comprising an outer jacket ( 8 ) which delimits a vacuum chamber ( 9 ), and a cryocooler cold head ( 10 ) installed therein, which has at least two cold stages ( 11, 12 ) and is at least partially surrounded by a radiation shield ( 13 ) is characterized in that at least two cold stages ( 11, 12 ) of the cold head ( 10 ) are separately individually connected in a heat-conducting manner to a heat-transferring device ( 14 a, 14 b ) which can be inserted into the neck or suspension tubes ( 3 a, 3 b ) of a cryostat ( 1 ) for keeping at least two different cryogenic liquids ( 18 a, 18 b ). The cooling device can be easily retrofitted into existing cryostat configurations, in particular, those containing superconducting magnets and without (or with minimum) adjustment to permit operation with no or little cryogen loss, even if several cryogens are used. |