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 4:
4. The refrigerator of claim 1 wherein said regenerator has three layers of differing materials for providing an optimum refrigerating capacity within a temperature range of between 35 to 80 K, said layers including: a first layer on the warm side of the regenerator that includes a 200 mesh copper-bronze material extending along about 40% of the regenerators total length; a second layer adjacent said first layer that includes a 120 mesh copper-bronze material extending along about 40% of the regenerators total length, and a third layer adjacent said second layer that includes 80 to 200 mesh copper-bronze material that extends along about 20% of the regenerators total length.