Patent · US Expired

Refrigerating unit

US5557944A · kind A · utility

20Cited by
5References
1Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 14, 1994
Grant dateSep 24, 1996
Priority date
Expiry dateFeb 14, 2014

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF25B2500/04
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A lubricant for a refrigerating unit uses a hydrofluorocarbon system refrigerant with a polyol ester system oil as its base oil. The purity of hydrofluorocarbon system refrigerant is set to a level higher than 99.95 wt % and the mixing of chlorine impurity in the system refrigerant is set at a level lower than 80 ppm. The performance and reliability of a refrigerating unit using the hydrofluorocarbon system refrigerant, such as R134a, can be enhanced by making the polyol ester system oil of a chemical compound having particular physical properties, by suppressing the equilibrium water content of refrigeration cycle and by limiting the residual volume.

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