| 摘要 |
PURPOSE:To reduce the amount of liquid helium by forming a liquid helium container into a hollow cylinder, and then making a vacuum container covering it as bucket type. CONSTITUTION:The liquid helium container 2 is formed into the hollow cylinder, and the vacuum container 3 is made as bucket type. Such a cryostat 7 makes it enough that the amount of the liquid helium 7 is small, and accordingly the heat penetration from outside is also small. Besides, since the surface area of the container 3 is small and extends only over the outer periphery of a flange junction, the decrease of vacuum degrees is gentle. Therefore, it is sufficient that the amount of the liquid helium is small, and the heat penetration reduces. As a result, the small amount of liquid helium evaporation is enough. |
