Patent ID: 11920576
Assignee: SUMITOMO HEAVY INDUSTRIES, LTD.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 10:
11. A method of monitoring a cryopump including
a first-stage cryopanel having an inner surface of the first-stage cryopanel disposed so as to surround an accommodation space for a condensed layer of gas, a second-stage cryopanel disposed so as to be surrounded by the inner surface of the first-stage cryopanel together with the accommodation space, and a cryocooler including a first cooling stage thermally coupled to the first-stage cryopanel and a second cooling stage thermally coupled to
the second-stage cryopanel,
the method comprising:
cooling the first-stage cryopanel to a temperature higher than a condensation temperature of the gas and cooling the second-stage cryopanel to a temperature equal to or lower than the condensation temperature of the gas;
depositing the condensed layer of the gas that enters the accommodation space from outside the cryopump through a cryopump intake port on the second-stage cryopanel; and
monitoring an amount of condensed gas in the accommodation space based on a change in the first-stage heat load incident on the inner surface of the first-stage cryopanel from outside the cryopump through the cryopump intake port,
wherein the cooling comprises controlling an operating parameter of the cryocooler to cool the first-stage cryopanel to a first-stage target temperature, and
wherein the monitoring comprises acquiring the operating parameter of the cryocooler and determining whether or not the amount of condensed gas exceeds a reference value by comparing the operating parameter of the cryocooler with a threshold value.