Gradient system
US4981597A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 1989 |
| Grant date | Jan 1, 1991 |
| Priority date | — |
| Expiry date | May 19, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2030/347
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
To supply a programmed gradient to a high pressure pump for introduction into a column, a mixer, degasser and accumulator communicates with the high pressure pump to supply fluid thereto, having a volume no more than 150 times the chamber volume of the high pressure pump. The mixer, degasser and accumulator includes temperature sensors which sense when the mixer, degasser and accumulator has been emptied to a level where it cannot respond to a demand for fluid from said high pressure pump and provides a signal to a low pressure pump which responds by cycling to again fill the mixer, degasser and accumulator. Upon receiving a demand signal, the low pressure pump fills by drawing fluid from a plurality of fluid sources to compose the gradient being used at that time, with the pump slowing during valve opening and closing so as to avoid cavitation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.