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. 13, 1979
Filed:
Dec. 23, 1977
James E Zimmerman, Boulder, CO (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
A simply constructed low input power cyclic cryogenic refrigerator suitable or cooling superconducting quantum interfering devices (SQUID) and similar instruments is provided. A Stirling machine having a multistage displacer and a piston as its only essential moving parts, with helium gas as the working fluid, achieves and maintains a temperature of substantially 8.5.degree. K. The working cylinder and displacer are separated by a tube and are fitted together precisely at steady-state operation rather than at room temperature. The displacer preferably is made of nylon and its cylinder of an epoxy-glass composite to provide the nearly optimum clearance required to maintain the 8.5.degree. K. temperature for continuous periods on the order of several weeks.