Diffusion-type NDIR gas analyzer with improved response time due to convection flow
US6255653A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 24, 2000 |
| Grant date | Jul 3, 2001 |
| Priority date | — |
| Expiry date | Oct 24, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/61
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A diffusion-type NDIR gas analyzer with an improved response time due to convection flow created by a temperature gradient between gas located within a waveguide and gas located within a diffusion pocket of space created between the waveguide and a semi-permeable membrane which surrounds the waveguide. The temperature gradient may be created by a thermally resistive radiation source that is not thermally isolated from the waveguide. The semi-permeable membrane is made of a hydrophobic material and has a thickness sufficient to provide its own structural integrity. The semi-permeable membrane can have a porosity less than approximately 50 microns and be comprised of ultra high molecular weight polyethylene or Teflon.RTM..
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.