Sub-kelvin temperature zone refrigeration mechanism

A sub-Kelvin temperature zone refrigeration mechanism, comprising a pulse tube refrigeration unit, first pre-cooling heat exchangers, a throttling refrigeration unit, second pre-cooling heat exchangers, an adsorption refrigeration unit, a third pre-cooling heat exchanger and a dilution refrigeration unit, wherein

• the pulse tube refrigeration unit comprises a pulse tube refrigeration heat exchanger, and the pulse tube refrigeration heat exchanger is connected with the throttling refrigeration unit through the first pre-cooling heat exchangers so as to pre-cool the throttling refrigeration unit;
• the throttling refrigeration unit comprises a throttling refrigeration heat exchanger, and the throttling refrigeration heat exchanger is connected with the adsorption refrigeration unit through the second pre-cooling heat exchangers so as to pre-cool the adsorption refrigeration unit;
• the adsorption refrigeration unit comprises an adsorption refrigeration heat exchanger, and the adsorption refrigeration heat exchanger is connected with the dilution refrigeration unit through the third pre-cooling heat exchanger so as to pre-cool the dilution refrigeration unit;
• and
• the dilution refrigeration unit comprises a dilution refrigeration heat exchanger, and the dilution refrigeration heat exchanger is a refrigeration terminal of the sub-Kelvin temperature zone refrigeration mechanism:
• wherein the throttling refrigeration unit comprises a throttling compressor, a throttling valve and the throttling refrigeration heat exchanger, an output end of the throttling compressor is connected with an input end of the throttling valve, an output end of the throttling valve is connected with an input end of the throttling refrigeration heat exchanger, and an output end of the throttling refrigeration heat exchanger is connected with an input end of the throttling compressor;
• and
• the first pre-cooling heat exchangers are located between the throttling compressor and the throttling valve and configured for cooling gas output by the throttling compressor.