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:
Feb. 08, 2000
Filed:
Mar. 11, 1998
Gregory W Swift, Santa Fe, NM (US);
David L Gardner, Los Alamos, NM (US);
The Regents of the University of California, Los Alamos, NM (US);
Abstract
An orifice pulse tube refrigerator (PTR) having a pulse tube and a reservoir with a compliance value C is provided with a variable acoustic impedance connecting the pulse tube and the reservoir. The variable acoustic impedance includes two or more variable impedances, which may be an inertance and valves forming variable resistive members, wherein the resulting acoustic impedance has a phase angle that is variable for improved cooling efficiency. The inertance may also be variable to further provide for varying the phase angle. In another improvement, an acoustic transmission line connects the pulse tube and a driver unit for recovering power from the pulse tube for return to the driver to further increase the PTR operating efficiency.