Low noise back pressure regulator for supercritical fluid chromatography
US8419936B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2010 |
| Grant date | Apr 16, 2013 |
| Priority date | — |
| Expiry date | Jun 20, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7904
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A drive mechanism for back pressure regulator used in liquid chromatography, supercritical fluid chromatography, or supercritical fluid extraction allows very fine automated control over a very wide range of pressures by combining a linear actuator compressing a spring, pushing a pin. The nozzle assembly of the regulator comprises a flow through chamber containing a diaphragm and a seat, in which the pin pushes the diaphragm against the seat, together with an upstream pressure sensor and electronic feedback control to the motor of the actuator. The BPR of the embodiments exhibits high pressure stability and extremely low pressure noise, even at moderate to high pressures. The exemplary BPR can be use at either constant pressure or to generate pressure programs where the pressure is varied versus time. Further, the nozzle assembly has a field-replaceable head, requiring no mechanical adjustment on replacement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.