Self-decompression valve mechanism and low temperature refrigerator adopting self-decompression valve mechanism

Abstract

The invention discloses a self-decompression valve mechanism and a corresponding low temperature refrigerator. The self-decompression valve mechanism comprises an air distribution valve (6) and a rotation valve (7); the back surface of the air distribution valve (6) is dividing into a high pressure surface (66) and a low pressure surface (65); the high pressure surface (66) and the low pressure surface (65) are separated through a third sealing ring (b3) which seals the air distribution valve (6) and a cover body (2); a pressure relief vent (61) which axially penetrates through an air distribution surface (64) and the low pressure surface (65) of the air distribution valve (6) is arranged on the air distribution valve (6); and the pressure relief hole (61) is capable of communicating a lowpressure access (22) of the cover body (2) with the back surface of the air distribution valve (6) so as to import low pressure airflow in the cover body (2) to the back surface of the air distribution valve (6). The low temperature refrigerator comprises the self-decompression valve mechanism. Through the setting of the pressure relief hole and the third sealing ring, the compression area is decreased, the positive acting force is reduced and the abrasion is decreased.

Description

technical field [0001] The invention relates to the technical field of low-temperature refrigerators, in particular to a self-decompression gas distribution mechanism which reduces positive pressure and wear by modifying the structure of the gas distribution valve, and a low-temperature refrigeration system using the self-decompression gas distribution mechanism. machine. Background technique [0002] A cryogenic refrigerator typified by a Gifford-McMahon (GM) refrigerator has an expander and a compressor for a working gas (also referred to as refrigerant gas). This type of refrigerator provides high-pressure airflow discharged from the compressor, and enters the push piston that is placed in the cylinder and reciprocates up and down through the gas distribution mechanism, exchanges heat with the cold storage material, and then expands in the expansion chamber, and then passes through the push piston. The piston flows out of the valve train and returns to the low-pressure c...

AI Technical Summary

Problems solved by technology

However, the high-pressure air hole 62 and the air hole 63 of the air distribution valve 6 have certain size and position requirements, so that the outer diameter D1 of the air distribution valve 6 cannot be too small, otherwise the high-pressure air hole 62 and the air hole 63 of the air distribution valve cannot be made.

In this way, the positive pressure of the joint is relatively large, and long-term operation will cause wear on the contact surface of the rotary valve 7 and the gas distribution valve 6, which will affect the performance of the equipment and reduce the reliability of the equipment.

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