Patent · US Expired

Food freezer

US5042262A · kind A · utility

43Cited by
4References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 8, 1990
Grant dateAug 27, 1991
Priority date
Expiry dateMay 8, 2010

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF25B2309/06
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

A food freezer having a mechanical refrigeration system comprising first and second closed-loop fluid circuits, wherein the first fluid circuit employs carbon dioxide as its refrigerant and transfers heat to the second fluid circuit, which in turn transfers heat to the environment or to another fluid circuit. In the first fluid circuit evaporator, carbon dioxide is maintained at pressures between 60.4 psig and 120 psig. In a preferred embodiment of the invention, the freezer employs at least two separate blowers or fans for circulation of air or other gas in the freezer enclosure. One blower/fan operates continuously to maintain circulation of cold air or gas in the freezer. The other blower/fan operates intermittently or at variable speeds to vary air flow across the evaporator, and thereby increase or decrease heat transfer from the freezer interior to the first fluid circuit evaporator to maintain the freezer interior at a desired temperature or within a desired temperature range.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.