Continuous flow metering apparatus
US4517302A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 15, 1982 |
| Grant date | May 14, 1985 |
| Priority date | — |
| Expiry date | Nov 15, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/2575
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Continuous flow metering apparatus and methods using liquid position sensors in conjunction with flow-stopping valves control (meter) fluid, e.g. sample/reagent/air, aspiration into a single conduit, such as in a continuous flow system. Air or other gas separates selected ones of the liquid segments. The volume of the aspirated segment is established by sensing a flow parameter of the segmented stream of a selected one of the sensors. A pulse is generated by the sensors (detectors), for example due to the change of light intensity at a liquidair interface traversing the conduit. The signal pulse from a sensor causes the actuation of a selected one of the valves and stops aspiration (flow) of the liquid by traversing the flow path in the conduit through an air segment. The valve cuts through air only. Therefore, the body of the valve does not contact reagent or sample liquid by this action and the risk of carryover contamination is avoided. With the aspiration cycle completed, the input end of the conduit, e.g. an aspirating probe, can consequently be immersed in different media and the cycle repeated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.