Patent · US Expired

Multiple stage cascade refrigeration system having temperature responsive flow control and method

US6324856A · kind A · utility

24Cited by
11References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 7, 2000
Grant dateDec 4, 2001
Priority date
Expiry dateJul 7, 2020

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF25B2700/21175
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

A refrigeration system having a flow control mechanism to selectively increase or decrease refrigerant flow in response to system temperature. In the preferred embodiment, a cascade refrigeration system having a high temperature first stage with a compressor, condenser, flow control device and heat exchanger. The low temperature second stage has a compressor, flow control device, evaporator and heat exchanger. The first stage is in a heat exchange relationship with the second stage through the common heat exchanger, which functions as condenser in the second stage. A controller responsive to temperature sensed at the second stage evaporator outlet operates a valve to increase or decrease refrigerant flow in the first stage. Increased refrigerant flow improves refrigeration system response to large heat loads, while maintaining efficient operation under normal conditions.

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