Patent · US Expired

Heater cycling for improved oil return

US6993920B2 · kind B2 · utility

11Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 30, 2004
Grant dateFeb 7, 2006
Priority date
Expiry dateMar 8, 2024

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02A40/963
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

A method comprises the steps of (a) providing a refrigeration unit having a refrigerated or heated space and at least one measured operating parameter, (b) providing heat to the refrigerated space when the at least one measured operating parameter exceeds a first threshold, (c) terminating provision of heat when the at least one measured operating parameter exceeds a second threshold, and repeating steps b–c when the at least one operating parameter falls below the first threshold. In using this method, the unit can be operated continuously, with substantially higher refrigerant mass flow and evaporator pressure then in the prior art. Higher refrigerant mass flow rate and higher evaporator pressure improve oil return to the compressor, thus reducing the like hood of compressor damage due to oil pump out.

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