Intake monitoring for accurate proportioning

Patent metadata

Field	Value
Publication number	US-9459239-B2
Application number	US-201113178814-A
Country	US
Kind code	B2
Filing date	Jul 8, 2011
Priority date	Jul 8, 2011
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

A fluid supply system configured for metering two or more fluids in controlled proportions, including a plurality of solvent supply lines, a pumping unit configured for taking in fluids from selected solvent supply lines and for supplying a pressurized mixture, a proportioning valve configured for modulating solvent composition by sequentially coupling selected ones of the solvent supply lines with the inlet of the pumping unit, a sensor configured for sensing process information in the fluid supply system, an analysis entity configured for analyzing the process information for determining reciprocating element related information at a beginning of fluid intake, and a control unit configured for switching the proportioning valve to sequentially couple selected ones of the solvent supply lines to the inlet of the pumping unit at one or more switching points based on the given metering scheme and based on the reciprocating element related information.

First claim

The invention claimed is:

1. A fluid supply system configured for metering two or more fluids in controlled proportions in accordance with a given metering scheme and for supplying a resultant mixture, the fluid supply system comprising:
a plurality of solvent supply lines, each fluidically connected with a fluid source providing a respective fluid;
a pumping unit comprising an inlet, an outlet, and a reciprocating element configured for intaking fluid supplied at the inlet and for supplying the pressurized fluid at the outlet, wherein the pumping unit is configured for taking in fluids from selected solvent supply lines and for supplying a pressurized mixture of the fluids at the outlet;
a proportioning valve interposed between the solvent supply lines and the inlet, the proportioning valve configured for modulating solvent composition by sequentially coupling selected ones of the solvent supply lines with the inlet;
a sensor configured for sensing process information in the fluid supply system relating to a fluid intake process of the pumping unit;
an analysis entity configured for analyzing the sensed process information and for determining as a result of the analysis, independently of a position of the reciprocating element within the pumping unit, the event of the beginning of a fluid intake process, wherein the analysis entity is further configured for determining reciprocating element related information at the event of the beginning of the fluid intake process; and
a control unit configured for switching the proportioning valve to sequentially couple selected ones of the solvent supply lines to the inlet of the pumping unit at one or more switching points during a duty cycle of the reciprocating element coordinated with the motion of the reciprocating element based on the given metering scheme and based on the reciprocating element related information,
wherein the control unit is configured for coordinating operation of the pumping unit and the proportioning valve for at least partially compensating for a discrepancy between an actual relationship between operation of the pumping unit and the proportioning valve, as indicated by the reciprocating element related information determined by the analysis entity, and a target relationship between operation of the pumping unit and the proportioning valve, as predefined for operating the fluid supply system.

2. The fluid supply system of claim 1 , wherein the analysis entity is configured for analyzing the sensed process information in terms of at least one predefined artifact criterion for determining at least one artifact feature in the sensed process information, and is configured for analyzing a relation between the at least one predefined artifact feature and the determined reciprocating element related information.

3. The fluid supply system of claim 2 , wherein the at least one predefined artifact criterion comprises at least one of the group consisting of an influence of gas bubbles in the fluid, an influence of leakage in the fluid supply system, an influence of compressibility of the fluid, a volume contraction resulting from a mixing of multiple components of the fluid, an influence of a temperature of the fluid, a thermal effect of mixing of different fluids, and an influence of adiabatic expansion of the fluid.

4. A sample separation system for separating components of a sample fluid in a mobile phase, the sample separation system comprising:
a fluid supply system according to claim 1 , the fluid supply system being configured to drive the fluid as the mobile phase through the sample separation system; and
a separation unit configured for separating components of the sample fluid in the mobile phase.

5. The sample separation system of claim 4 , further comprising at least one of:
a sample injector configured to introduce the sample fluid into the mobile phase;
a detector configured to detect separated components of the sample fluid;
a collection unit configured to collect separated components of the sample fluid;
a data processing unit configured to process data received from the sample separation system; and
a degassing apparatus for degassing the mobile phase.

6. The fluid supply system of claim 1 , further comprising at least one of:
during an intake movement of the reciprocating element, when fluid is drawn in via the inlet, or between intervals during which the fluid is drawn in via the inlet, the proportioning valve performs switching between different solvent supply lines;
the proportioning valve comprises a plurality of switching valves, with the switching valves being sequentially actuated during an intake movement of the reciprocating element of the pumping unit;
the proportioning valve comprises at least one multi-port selection valve;
the proportioning valve is configured for selecting a selected one of the solvent supply lines corresponding to a multiplexer scheme; and
predefined portions of an intake movement of the reciprocating element are assigned to different solvents that are drawn into the pumping unit, wherein proportioning is done by metering of one of volumetric packets, time slices, and position of the reciprocating element.

7. The fluid supply system of claim 1 , wherein the sensor is arranged hydraulically at at least one of the following positions:
a position between the proportioning valve and the pumping unit;
a position within the solvent supply lines;
a position within the proportioning valve;
a position upstream of an intake valve arranged directly upstream of the pumping unit; and
a position within an intake valve arranged at a low pressure side of the pumping unit.

8. The fluid supply system of claim 1 , comprising at least one of:
the control unit is configured for coordinating operation of the pumping unit and the proportioning valve for at least partially compensating for a potential discrepancy between an actual fluid motion on the intake side of the pumping unit resulting from a relationship between operation of the pumping unit and the proportioning valve, as indicated by the determined reciprocating element related information, and a target motion of the fluid as desired based on a target relationship between operation of the pumping unit and the proportioning valve, as predefined for operating the fluid supply system;
the control unit is configured for controlling operation of the fluid supply system to at least partially compensate for at least one of a steering inaccuracy, a mechanical inaccuracy, and a non-ideal valve function;
the control unit is configured for controlling operation of the fluid supply system in accordance with at least one of the group consisting of the sensed process information, fluid intake information relating to the event of the beginning of the fluid intake process, and the reciprocating element related information;
the control unit is configured for controlling fluid intake by the pumping unit based on the reciprocating element related information to adjust a size of an initial fluid packet to be taken in during the intake process;
the control unit is configured for controlling fluid intake by the pumping unit based on the reciprocating element related information to adjust a size ratio of the fluid packets to be taken in during the intake process;
the control unit is configured for controlling fluid intake by the pumping unit based on the reciprocating element related information to adjust a ratio of total amounts of each solvent taken in during the intake process;
the control unit is configured for controlling fluid intake by the pumping unit based on the reciprocating element related information to correct a size of fluid packets taken in by the pumping unit;
the control unit is configur

Assignees

• Witt Klaus
• Choikhet Konstantin
• Agilent Technologies Inc

Inventors

• Witt Klaus
• Choikhet Konstantin

Classifications

• G01N30/34 Primary

  of fluid composition, e.g. gradient (G01N30/36 takes precedence) · CPC title

• Y10T137/2499

  Mixture condition maintaining or sensing · CPC title