Joule-Thompson cooling apparatus comprising two counterflow heat exchangers

摘要

The invention relates to a cooling apparatus 10 for cooling a detector 52, said apparatus comprising an inner and an outer counterflow heat exchange, 12 and 14 respectively, for a first and a second gas respectively, located in a heat-insulating housing 16, the inner counterflow heat exchanger being disposed inside a part of the length of the outer counterflow heat exchanger, and the inner counterflow heat exchanger being spatially separated from the outer counterflow heat exchanger by an outer casing 18. The outer casing then has a dividing plate 32 between an expansion nozzle 28 for the first gas, located at the end of the inner counterflow heat exchanger, and the rest of the outer counterflow heat exchanger. The rest of the outer counterflow heat exchanger, which extends beyond the inner counterflow heat exchanger, is disposed inside the outer casing. Downstream of an expansion nozzle 44 for the second gas, located at the end of the outer counterflow heat exchanger, the outer casing is closed by an end plate 46. In addition, in the region in which it is surrounded by the outer counterflow heat exchanger, the outer casing has a number of openings.