Sampler incorporating pressure balanced check valve
US4557151A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 7, 1983 |
| Grant date | Dec 10, 1985 |
| Priority date | — |
| Expiry date | Jan 7, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2001/2057
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sampling apparatus having a pressure balanced check valve is set forth in the preferred and illustrated embodiment. The sampling system includes an elongate probe which is driven by a diaphragm motor. The probe extends through a fixed housing and terminates at a sample collection head. The probe is provided with a lengthwise passage in it. Sample is collected from a pumping apparatus comprising a reciprocating anvil and a fixed hammer. These two unyielding members are reciprocated toward one another. They capture, therebetween, a resilient plug having a dished area which collapses on pressure. This forces sample from the dished area. It flows into a passage, into the probe, through a check valve. The check valve is pressure balanced so that the force required to overcome it is not dependent on line pressure, sample collection container back pressure and the like. Dead volume is reduced to an absolute minimum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.