| abstract |
The present invention relates to a pulse tube refrigerator used in a non-vacuum atmosphere such as a helium atmosphere, and reliably reduces heat loss due to convection of the atmosphere gas even when operated in a non-vacuum atmosphere. Is an issue. A pulse tube refrigerator used in a helium atmosphere, a first-stage regenerator 7, a second-stage regenerator 26, a first-stage pulse tube 10, a second-stage pulse tube 40A, Other than the stage corresponding position, the first stage cooling stage 30 and the second stage cooling stage 25 have a stage corresponding position corresponding to the first stage cooling stage 30 in the middle of the second stage pulse tube 40A. The heat exchange part 45 which improved the heat exchange efficiency compared with the site | part is provided. [Selection] Figure 1 |