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. 19, 1986
Filed:
Nov. 18, 1983
Applicant:
Inventors:
F William Pirtle, Stow, MA (US);
Harry G Nicoll, Norwell, MA (US);
Peter K Bertsch, Harvard, MA (US);
Assignee:
Helix Technology Corporation, Waltham, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F25B / ;
U.S. Cl.
CPC ...
62-6 ; 60520 ;
Abstract
A cryocooler 8 is described which has a low magnetic signature in which a ceramic displacer 10 reciprocates within a helium impenetrable cold finger cylinder 12. A cyrogenic refrigerator formed by the displacer and the cold finger cylinder cools a cold space 22 to cryogenic temperature. The cold space 22 is magnetically shielded from a drive motor 18 which both drives the displacer 10 and compressor pistons 14, 15, 16. The motor is magnetically shielded by means of magnetic shields 70, 72, 74, 90, 76, 78, 80, 82.