| 摘要 |
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 to achieve a high compression ratio to expel a bubble, and automatically apportioning an optimal amount of piston travel necessary to keep gases compressed into the solution and maintain steady flow. |
