Compact and low fuel consumption flame ionization detector with flame tip on diffuser
US5576626A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 17, 1995 |
| Grant date | Nov 19, 1996 |
| Priority date | — |
| Expiry date | Jan 17, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2030/025
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A compact and low fuel consumption flame ionization detector includes a precisely pored metallic disk or a silicon micro-machined diffuser plate through which the sample gas tube extends a minimum distance (less than 2 mm). The oxidant flows into the detector in a direction parallel to a plane of the diffuser plate, passes into a small cavity under the diffuser, and then passes through a large number of very small holes formed in the diffuser plate before encountering the sample gas flow at the end of the gas tube. A narrow diameter collector is closely spaced to the end of the gas tube. The direction of feeding the air and the diffuser plate (which acts as a baffle) provide laminar flow and eliminate the flicker noise which would otherwise occur due to the air flow inlet being located very close to the gas tube end. The FID is vertically compact and operates at a high electric field strength, exceeding 90 V/mm. The FID has a low fuel flow, typically 12-15 ml/min and therefore a low oxidant flow rate, typically 120-150 ml/min, advantageous to the operation of a portable gas chromatograph. The compactness of the FID also requires less electrical power to heat the detector to operati…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.