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:
Aug. 16, 2011
Filed:
Jan. 13, 2005
Applicant:
Ralph C. Longsworth, Allentown, PA (US);
Inventor:
Ralph C. Longsworth, Allentown, PA (US);
Assignees:
Sumitomo Heavy Industries, Ltd., Tokyo, JP;
SHI-APD Cryogenics, Inc., Allentown, PA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F25B 9/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
The problems of reducing the torque required to turn the valve, eliminating wear dust, and extending the life of the valves in Gifford McMahon (G-M) type multi-port pulse tube refrigerators are solved by using a rotary spool valve having radial clearance to control flow to and from the regenerator, and using face seal ports on the end of the spool to control flow to and from the pulse tubes.