Patent ID: 7205533

Claim:
Cooling apparatus ( 10 ) for cooling a detector ( 52 ), the cooling apparatus including an inner and an outer countercurrent heat exchanger ( 12 and 14 , respectively) for a first and a second gas in a thermally insulating housing ( 16 ), the inner countercurrent heat exchanger ( 12 ) being arranged within a sublength of the outer countercurrent heat exchanger ( 14 ), and the inner countercurrent heat exchanger ( 12 ) being spatially separated from the outer countercurrent heat exchanger ( 14 ) by an outer sleeve ( 18 ), wherein a) the outer sleeve ( 18 ) has a partition plate ( 32 ) between an expansion nozzle ( 28 ) for the first gas located at the end of the inner countercurrent heat exchanger ( 12 ) and the remaining part of the outer countercurrent heat exchanger ( 14 ), b) the remaining part of the outer countercurrent heat exchanger ( 14 ), which projects beyond the inner countercurrent heat exchanger ( 12 ), is arranged within the outer sleeve ( 18 ), c) the outer sleeve ( 18 ) is terminated by an end plate ( 46 ) below an expansion nozzle ( 44 ) for the second gas located at the end of the outer countercurrent heat exchanger ( 14 ), d) the outer sleeve ( 18 ) has a number of apertures in the region in which it is surrounded by the outer countercurrent heat exchanger ( 14 ).