Nonsymmetrical valve
US5010921A · kind A · utility
32Cited by
5References
4Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 17, 1989 |
| Grant date | Apr 30, 1991 |
| Priority date | — |
| Expiry date | Jul 17, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/86863
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A conventional injection valve, such as used in high performance liquid chromatography apparatus, having six ports and three channels for connecting the ports in two different positions, is modified so that one of the channels is longer than the other two. In this way, when the valve is switched to the load position, one of the ports is always connected to the channel prior to the other port being connected. This improvement in the valve makes the valve more accurate and reduces undesirable mixing of sample and mobile phase in the valve when injecting small quantities of sample.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.