Patent · US Expired

Liquid chromatography controller

US4618935A · kind A · utility

3Cited by
9References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 6, 1984
Grant dateOct 21, 1986
Priority date
Expiry dateJan 6, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N30/34
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A new and improved controller for creating a linear gradient dual solvent flow pattern in a dual pump liquid chromatography system wherein one pump pumps one solvent and the other pump pumps the second solvent, the controller comprising a clock for producing a timing signal; digiswitches for providing first and second digital signals representative of initial and final values for one of two solvents; a difference circuit for producing a third digital signal representative of the difference between the initial and final values; a digiswitch for providing a fourth digital signal representative of the time duration of the linear gradient; a binary divider for regulating the timing signal to produce a signal proportional to the fourth digital signal; a binary rate multiplier for proportioning the regulated timing signal to the third digital signal; circuitry for producing a fifth digital signal from the proportional regulated timing signal, whereby the fifth digital signal represents the dividend of the third digital signal divided by the fourth digital signal; and circuitry for inputting signals to each of the pumps to set the flow rates thereof, said circuitry being regulated by said…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.