Ultra-low temperature vacuum measurement calibration device and method based on GM refrigerator cooling

The invention discloses an ultralow-temperature vacuum measurement and calibration device and method based on GM refrigerator cooling, and belongs to the technical field of measurement and calibration. The device is characterized in that the measuring end of a three-way connecting piece is connected with a standard vacuum gauge, the air exhaust end is connected with an air exhaust system, and the air inlet end is connected with an air supply system and connected with the upper portion of a measuring pipe; the lower part of the measuring tube is welded with the upper part of a calibration chamber in the cold shield; the lower part of the cold shield is connected with a primary cold head of the GM refrigerator, the lower part of the calibration chamber is connected with a temperature control block, and the temperature control block is connected with a secondary cold head of the GM refrigerator; a connecting hole is reserved in the middle of the calibration chamber, a through hole is formed in the cold shield, o