The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 10, 2001
Filed:
Apr. 24, 2000
Jin Lin Gao, Wescosville, PA (US);
IGCAPD Cryogenics, Inc., Allentown, PA (US);
Abstract
A two-stage pulse tube refrigerator comprises a pressure wave generator-compressor, first stage and second stage regenerators, first stage and second stage pulse tubes, heat exchangers and a hybrid phase shift mechanism for the first and second stage pulse tubes. The second stage phase shift mechanism includes double fixed orifices while the first stage shifter is an arrangement including one of a) 4 valves, b) 5 valves c) 2 active buffers or d) 3 active buffers. The double fixed orifice phase shifter is located either at room temperature or is thermally connected with the first stage cold end. Two-stage pulse tube refrigerators with a hybrid phase shifter have increased second stage regenerator performance at lower temperature. Pressure drop through the valves and compressor power consumption are decreased, and losses from phase interaction between each stage are eliminated.