Patent Document ID: 6065295
Application ID: 09077345

Base Claim:
1. A cryogenic refrigerator for producing temperatures within a given low temperature range, said refrigerator including a single-stage cold head and a regenerator operatively connected to said cold head, said regenerator having at least two layers of different materials through which a working fluid is circulated, said materials being selected so that the cold head has an optimum refrigerating capacity between 15K and 80K, wherein said regenerator contains a first layer of bronze mesh material on the warm side of the regenerator and a second layer of lead material on the cold side of the regenerator.

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Claim 2:
2. The refrigerator of claim 1 wherein said regenerator has three layers of differing materials that include a first layer of bronze mesh located on the warm side of the regenerator extending along about two to three sevenths of the regenerators total length, a second layer adjacent the first layer of bronze mesh having a mesh size that is smaller than that of said first layer extending along about two to three sevenths of the regenerators total length and a third layer of lead spheres or sintered lead material extending along about one to two sevenths of the regenerators total length.