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:
Mar. 03, 2009
Filed:
Nov. 15, 2005
Mingyao Xu, Emmaus, PA (US);
Ralph Longsworth, Allentown, PA (US);
Mingyao Xu, Emmaus, PA (US);
Ralph Longsworth, Allentown, PA (US);
Sumitomo Heavy Industries, Ltd., Tokyo, JP;
SHI-APD Cryogenics, Inc., Allentown, PA (US);
Abstract
A two-stage pulse tube refrigerator having a compact design, low vibration and low heat loss is provided where at least the 2stage is co-axial but preferably, both stages are co-axial with the second stage pulse tube being central and the first stage pulse tube occupying the annular space between the second stage pulse tube and the first stage regenerator. Convection losses associated with different temperature profiles in the pulse tubes and regenerators are minimized by shifting the thermal patterns in the pulse tubes relative to the regenerators by one or more of spacers in the regenerators, physical differences in length with gas channel connections, adjustment of dc flow, and thermal bridges.