The chiller adopts multi-environmental environmental protection refrigerant with independent intellectual property rights. The cold box adopts the unique secondary foaming technology to achieve good insulation effect. The refrigeration system uses conventional air-conditioning compressors, and other components are easily available. Compared with traditional Sterling and GM machines, the chiller does not require regular maintenance, high reliability, and long service life. The liquefier has a one-button power-on function, and automatically enters the liquefaction mode after a key is turned on.