Patent ID: 7992394

Claim:
A cold trap provided in a pumping path connecting a volume subject to pumping to a vacuum pump, causing a portion of a gas taken in from the volume to the vacuum pump via the pumping path to be frozen on the surface of the cold trap, and capturing the gas accordingly, the cold trap comprising: a cold panel provided in the 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, at the temperature exceeding the non-liquefaction temperature range, a pressure in the pumping path 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, wherein the controller controls the refrigerator so that the pressure in the pumping path does not exceed the pressure at the triple point of the gas frozen on the cold panel, wherein when the pressure in the pumping path exceeds an upper limit pressure, the controller returns the pressure in the pumping path to a pressure equal to or below the upper limit pressure by cooling the cold panel.