Bubble detection and recovery in a liquid pumping system
USRE37553E1 · kind E1 · reissue
Assignee
Inventors
Key dates
| Filing date | Feb 9, 1999 |
| Grant date | Feb 19, 2002 |
| Priority date | — |
| Expiry date | Feb 9, 2019 |
Classification
- Technology area (CPC —)General
Abstract
A serial, dual piston high pressure fluid pumping system that overcomes the difficulties of gas in the fluid stream without the need for added mechanical valves or fluid paths. A bubble detection and recovery mechanism monitors compression and decompression volumes of the serially configured dual pump head pump, and the overall system delivery pressure. Bubble detection is effected by sensing a ratio of compression to decompression volume and determining if the ratio exceeds an empirical threshold that suggests the ratio of gas-to-liquid content of eluent or fluid in the system is beyond the pump's ability to accurately meter a solvent mixture. The magnitude of the ratio of compression to decompression volume indicates that either the intake stroke has a bubble or that the eluent has a higher-than-normal gas content. Once a bubble has been detected, recovery is effected by forcing the pump into a very high stroke volume with the compression and decompression stroke limits constrained to obtain the largest delivery stroke compression ratio that will expel a bubble or solvent that has detrimental quantities of gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.