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:
Nov. 21, 1978
Filed:
Aug. 24, 1976
Joseph Bytniewski, Grenoble, FR;
Patrice Chovet, Bernin, FR;
Jean-Pierre Gabillard, Sassenage, FR;
Roger Prost, Saint Egreve, FR;
Abstract
A miniature open circuit refrigerator of the Joule-Thompson type, functions as a demand cryostat by virtue of a pressure-operated refrigerant supply control. The refrigerant fluid under high pressure is introduced at a first relatively rapid flow rate into the cryostat through a calibrated opening that is fully open during the initial or start-up period of the device, for rapid cool down. This calibrated opening is thereafter at least partially closed by a valve which is urged open by a spring and which is urged closed, against the action of the spring, by a bellows containing a gas at high pressure and which is exposed on its outer side to at least a portion of the pressure of the refrigerant fluid. Upon the fall in pressure of the stored refrigerant fluid, toward the end of the start-up, the bellows expands so as at least partially to close the valve, thereby to decrease the flow of refrigerant during the final portion of the cool-down period and during the steady state or on-stream operation of the device. The invention is particularly applicable for the rapid cool down of infrared detection probes.