JPS648370A - Cryopump - Google Patents

Abstract

PURPOSE:To contrive reduction in time to attain a high vacuum, in a device in which a condensing apparatus being cooled to an extremely low temperature by a refrigerant is housed in a casing which is connected to an apparatus forming a high vacuum chamber, by fitting noncondensable gas absorbing fibrous activated-carbon onto the condensing apparatus. CONSTITUTION:A cryopump 1 comprises a casing 5 connected to a frame body 3 having a chamber 2 to be vacuumized to a high vacuum, a condensing apparatus 7 being cooled to an extremely low temperature by a refrigerant having been cooled by a refrigeration unit 6, and a radiation shield 8 which is arranged between the condensing apparatus 7 and the casing 5 and cut off the radiant heat from the outside. The condensing apparatus 7 is made up of a pipe 9 in which the refrigerant flows, and a cryopanel 10 having been fitted to this pipe 9, and the cryopanel 10 comprises a cylindrical part 11, and a plurality fins 12 fitted radially around the outside thereof. In this case, a cloth woven out of a fibrous activated carbon is adhered to the fins 12 as a adsorbing layer 13, so that the enhancement in the adsorbing velocity can be achieved.