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. 04, 1981
Filed:
Feb. 27, 1980
James E Zimmerman, Boulder, CO (US);
Donald B Sullivan, Boulder, CO (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
A single stage, twin piston cryogenic refrigerator for cooling supercondung devices. The refrigerator uses helium as the heat transfer medium and is constructed with two nested, concentric pistons, an inner piston and an outer piston, mounted in a cylinder and driven 90.degree. out of phase by a common crankshaft. The inner piston extends through and below the outer piston and is received in a stationary insert mounted in the cylinder. The outer piston has a first piston face which forms a compression space with the stationary insert while the inner piston has a second piston face which forms an expansion space with the cylinder and the insert. The inner piston is formed with upper and lower piston halves joined by a flexible joint positioned in the compression space. Cylindrical regenerator gaps are present at the interface of the inner piston with the stationary insert and at the interface of the stationary insert with the cylinder.