Patent ID: 7565809

Claim:
A circulation type liquid helium recondensation device with a contaminant-purging function comprising: a pump which pumps helium gas evaporating from a liquid helium storage tank a refiner connected to the liquid helium storage tank through a first passage, which refines the pumped helium gas; a condensing pot connected to the refiner through a second passage, which liquefies the gas; and a third passage though which the liquefied helium is returned to the liquid helium storage tank; and a discharge circuit connected to the first passage between the refiner and the liquid helium storage tank, wherein the pump is connected to the discharge circuit through a normally closed valve, wherein a heater is provided in the refiner, wherein in a contaminant discharge operation, the normally closed valve is opened and contaminants that vaporize by heating the refiner by the heater are pumped by the pump and discharged to the atmosphere via said discharge circuit.