Method of purging trapped gas from a system fluid contained in an actuation valve
US7169616B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 2003 |
| Grant date | Jan 30, 2007 |
| Priority date | — |
| Expiry date | Aug 18, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/2575
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for delivering repetitive, precision, low volume liquid dispensing from a dispensing orifice of a non-contact liquid dispensing apparatus. An elongated communication passageway of the dispensing apparatus is defined by interior walls having one end in fluid communication with a system fluid reservoir and an opposite end terminating at the dispensing orifice. A system fluid is placed in the communication passageway extending substantially continuously from the system fluid reservoir to the dispensing orifice. A relatively small volume of gaseous fluid is aspirated through the dispensing orifice, and into the communication passageway in a manner such that the gaseous fluid extends substantially continuously across the transverse cross-sectional dimension of the communication passageway. Subsequently, a dispensing liquid is aspirated through the dispensing orifice and into the communication passageway in a manner such that the relatively small volume of aspirated gaseous fluid forms a minute, unitary air gap fully enclosed between the interior walls of the communication passageway and a liquid interface between the system fluid and the dispensing liquid contain…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.