Patent ID: 8671698

Claim:
A portable cryogen liquefaction plant system comprising: a dewar comprising a vacuum chamber, a storage portion within the vacuum chamber for containing cryogen, and a neck portion; a cryocooler cold head comprising a hot end and a cold end, the cold end of the cold head received by the neck portion of the cryostat having a first stage cooling station, a first stage pulse tube, a first stage regenerator, a second stage cooling station, a second stage pulse tube, a second stage regenerator, and a condenser thermally coupled to the second cooling station; and a pre-cooling heat exchanger mounted upon and thermally coupled to the second stage pulse tube, the heat exchanger comprising a plurality of fins; radiation baffles mounted to the cold head within the neck portion of the dewar below the condenser, such that when the cryocooler is turned off, the radiation baffles reduce heat radiation losses to the cryogen in the storage portion of the dewar; a compressor coupled to the cryocooler cold head, for providing compressed gas to power the cold head; and a gas inlet line providing cryogen to a top of the neck of the dewar; cryogen from the gas inlet line flowing over the cold head of the cryocooler and being pre-cooled without being confined to a pathway of tubing, the pre-cooling fins on the second stage pulse tube cooling the cryogen by natural convection.