Cold trap and cold trap regeneration method
AssigneeSumitomo Heavy Industries, Ltd.
InventorKen Oikawa
Life of this patent
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Abstract
A cold trap is provided with a cold panel provided in a pumping path such that the panel is exposed, a refrigerator thermally coupled to the cold panel and operative to cool the cold panel; and a controller configured, in a regeneration process for evaporating a gas frozen on the surface of the cold panel and discharging the gas outside using the vacuum pump, to control the refrigerator so as to raise the temperature of the cold panel to a temperature exceeding a non-liquefaction temperature range and to adjust a pressure in the pumping path at the temperature so that the gas frozen on the surface of the cold panel is evaporated without being melted, the non-liquefaction temperature range being a range in which it is guaranteed that a gas frozen on the surface of the cold trap is evaporated without being melted.
Claims17
A cold trap, comprising:
- a cold panel;
- a refrigerator comprising a cooling stage configured to cool the cold panel;
- a temperature sensor configured to measure a temperature of the cold panel;
- and
- a controller configured to control a regeneration process of the cold panel, the regeneration process comprising raising the temperature of the cold panel to a temperature exceeding a non-liquefaction temperature range of a gas frozen on a surface of the cold trap,
- wherein the controller is configured to control the temperature of the cold panel based on measurement of the temperature sensor so that an ambient pressure around the cold panel is maintained in a pressure range in which the gas frozen on the surface is evaporated without being melted,
- wherein the temperature sensor is provided in the cooling stage,
- wherein the cold trap further comprises a pressure sensor configured to measure the ambient pressure around the cold panel,
- wherein the controller is configured to control the refrigerator to temporarily cool the cold panel when a measured ambient pressure exceeds a permitted pressure range.
A cold trap regeneration method, comprising:
- raising a temperature of a cold panel to a temperature exceeding a non-liquefaction temperature range of a gas frozen on a surface of the cold panel;
- and
- discharging the gas frozen on the surface from the cold panel,
- wherein the discharging comprises controlling the temperature of the cold panel based on measurement of a temperature sensor so that the gas frozen on the surface is allowed to sublimate,
- wherein the temperature sensor is configured to measure a temperature of a cooling stage of a refrigerator for cooling the cold panel,
- wherein the discharging comprises temporarily cooling the cold panel when an ambient pressure around the cold panel exceeds a permitted pressure range.
A regeneration controller for a cold trap regeneration process,
- wherein the regeneration process comprises raising a temperature of a cold panel to a temperature exceeding a non-liquefaction temperature range of a gas frozen on a surface of the cold panel, and discharging the gas frozen on the surface from the cold panel,
- wherein the controller is configured to control the temperature of the cold panel based on measurement of a temperature sensor so that an ambient pressure around the cold panel is maintained in a pressure range in which the gas frozen on the surface is evaporated without being melted,
- wherein the temperature sensor is configured to measure a temperature of a cooling stage of a refrigerator for cooling the cold panel,
- wherein the cold panel is temporarily cooled when the ambient pressure around the cold panel exceeds a permitted pressure range.
Dependencies are inferred from the claim text.