Methods and apparatus for operating a refrigeration system
US5410889A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 14, 1994 |
| Grant date | May 2, 1995 |
| Priority date | — |
| Expiry date | Jan 14, 2014 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25B2400/13
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A refrigeration system of the type having an economizer cycle is provided with a null cycle, in addition to heating and cooling cycles, without shutting a compressor prime mover down, to preserve air flow in a conditioned space. First, second and third controllable valves respectively: (1) select main and auxiliary condensers, (2) open and close a liquid line, and (3) open and close a line which provides a warm liquid to an economizer heat exchanger. The valves are controlled in at least one predetermined open/close pattern during a null cycle, and preferably in a plurality of selectable predetermined open/close patterns, to provide a null cycle at any instant which substantially matches the net heat gain or loss taking place in the conditioned space. Thus, the temperature of the served space will be more apt to remain in a null temperature range close to set point, providing smoother and more accurate control over the temperature of the conditioned space for longer shelf life of perishables stored therein. The system achieves the latter by controlling a bypass value according to the load of the compressor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.