Patent · US Expired

Miniature mixed gas refrigeration system

US6151901A · kind A · utility

16Cited by
30References
7Claims
0Family size

Assignees

Inventors

Key dates

Filing dateOct 12, 1995
Grant dateNov 28, 2000
Priority date
Expiry dateOct 12, 2015

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF28F2260/00
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

A miniature mixed gas refrigeration system is disclosed, having a coaxial catheter with an inner high pressure supply lumen and an outer low pressure return lumen. The gas mixture is pressurized by a compressor to a pressure less than 420 psia, for safety reasons. The distal portion of the outer lumen contains a micro-miniature heat exchanger constructed of laminated plates or sheets. The plates or sheets establish high pressure and low pressure passageways, with high surface area, having a tortuous path for the gas flow to maximize heat exchange. The high pressure outlet of the heat exchanger is connected to a Joule-Thomson expansion element where the high pressure gas is expanded isenthalpically to a lower temperature at least as low as 180K. This low temperature gas cools a heat transfer element mounted in the outer wall of the catheter, to cool an external object. Return gas flows back through the heat exchanger to pre-cool the incoming high pressure gas mixture.

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