Sample metering valve for a sample preparation system
US4866996A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1987 |
| Grant date | Sep 19, 1989 |
| Priority date | — |
| Expiry date | Jun 16, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N1/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sample metering valve for both liquid samples and slurry samples with entrained gas bubbles. The sample metering valve for liquids is comprised of a piston with sample chambers formed in the side thereof said piston moving freely into and out of a cylinder having an aperture matching the size of the piston. Sealing is provided by a seal which has no dead volume which cold flows under a spring bias to maintain the seal under various operating conditions. The sample metering valve for slurry samples includes a syringe embodiment having separately moving piston and valve in a cylinder. The syringe valve sucks up sample with a piston, isolates the sample with the valve and compresses the entrained gas bubbles with the piston. Another embodiment uses three, three way valves which are coupled to a pump and a means to compress the sample. The valves are operated to suck a portion of sample up into the tubes connecting the valves, isolate the sample from the sample container, compress the sample using the compressed gas and trap a known volume of the compressed sample in the tube between valves. The trapped sample is then flushed out of the system with diluent to prepare the sample for a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.