A Liquid Helium Recondensation Cryogenic Refrigeration System with Mechanical Vibration Isolation

Abstract

The invention belongs to the technical field of cryogenic refrigeration equipment, in particular to a liquid helium recondensation cryogenic refrigeration system isolated by mechanical vibration. The system of the invention includes a closed-cycle refrigerator system, a liquid helium recondensation refrigeration vibration isolation system and a temperature feedback control system. The invention adopts a closed-cycle refrigerator system to achieve a low temperature as low as 4.2 K under the condition of almost no consumption of helium and liquid helium. The invention generates and maintains liquid helium through the liquid helium recondensation refrigeration vibration isolation system, which not only effectively isolates the low-frequency vibration generated during the operation of the closed-cycle refrigerator, but also solves the problem of large temperature fluctuations in the traditional closed-cycle refrigerator. Through the temperature feedback control system, the present invention can not only control the liquid level height of the liquid helium generated by re-condensation, but also realize temperature-variable regulation. The invention is suitable for the ultra-high vacuum environment which needs to be baked at high temperature.

Description

technical field [0001] The invention belongs to the technical field of low-temperature refrigeration equipment, and in particular relates to a mechanical vibration-isolated liquid helium recondensation low-temperature refrigeration system. Background technique [0002] Low temperature environment refers to the environment below -180°C (93.15 K), which has important applications in the fields of physics, chemistry, materials, biology, national defense, and information. With the development of science and technology, cutting-edge and precise scientific research and technical applications not only require an environment close to extremely low temperature (4.2 K), but also require a low-vibration and ultra-high vacuum environment. At present, most cryogenic refrigeration equipment that meet the above indicators need to consume scarce and expensive liquid helium, and the operating cost is relatively high. In order to get rid of the extreme dependence of cryogenic refrigeration e...

AI Technical Summary

Problems solved by technology

However, the working principle of the closed-cycle refrigerator leads to periodic changes in the cooling power, and the refrigeration vibration isolation technology through the heat exchange of helium still has limitations such as low cooling power and large temperature fluctuations on the vibration isolation interface.

For these reasons, the refrigeration efficiency and temperature stability of cryogenic refrigeration systems without liquid helium consumption are still lower than those of cryogenic refrigeration systems that consume liquid helium.

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