Laboratory freezer appliance
US5142872A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 8, 1991 |
| Grant date | Sep 1, 1992 |
| Priority date | — |
| Expiry date | Jul 8, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25D2400/10
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A laboratory freezer appliance providing a usable storage space on the order of 5 to 20 cubic feet capable of storage temperatures of -160.degree. C. and lower including an insulated freezer chamber, heat transfer tubes in proximity to the freezer chamber carrying liquid argon at ultra-low temperatures which absorbs heat from the freezer chamber thereby vaporizing the argon in the heat transfer tubes; a closed cycle, hermetically-sealed free piston Stirling cycle heat pump providing a cold end above a vertical displacer driven by a linearly reciprocating piston at a delta T to the freezer chamber of about -13.degree. C.; a condensing chamber surrounding the cold end of the heat pump for condensing argon vapor to the argon liquid; and a distributor for distributing liquid argon from the condensing chamber to the heat transfer tubes and returning argon vapor to the condensing chamber, all without mechanical pumping of the argon, in a continuous, closed cycle refrigeration system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.