The multi-stage low temperature cooling system which possesses the 2nd step of the same axis

摘要

Multi-stage low temperature cooling system 100 includes the pulse tube expander 130 of the 2nd step of the same axis where pulse tube 132 has been located inside regenerator 131 of the 2nd step. With 1 execution forms, as for the internal wall of the regenerator functioning it does as an external wall of the pulse tube. With another execution form, the annular gap exists with the external walls of the internal wall and the pulse tube of the regenerator. The gap it is low like pressure environment of the space, low can be maintained to the pressure which gets near to the vacuum environment and the fluid by arranging the gap which is communicated around the low temperature cooling system. 2nd possesses the pulse tube inside the annular regenerator and is unified structure of the step offers some latent advantages of being superior than the former multi-stage low temperature cooling system. Selective figure Figure 1