Method and apparatus for sample injection in liquid chromatography

Patent metadata

Field	Value
Publication number	US-9618128-B2
Application number	US-201414529947-A
Country	US
Kind code	B2
Filing date	Oct 31, 2014
Priority date	Jan 31, 2005
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

The present invention provides a method and apparatus for substantially eliminating destructive transients of pressure or flow rate which can degrade the efficiency and useful lifetime of chromatography columns. The present invention enables a substantially constant flow of mobile phase liquid to be maintained through the chromatography system by eliminating the flow blockage interval associated with the actuation of sample injection valves. The present invention further provides a method to reduce the pressure and flow rate transients associated with pressurization of the sample loop contents when the sample loop is introduced to chromatography system delivery pressure.

First claim

What is claimed is:

1. A rotary shear-seal injection valve comprising:
a stator having a plurality of stator ports, at least one of said stator ports being in fluid communication with a pump; and
a rotor rotatably abutting said stator, said rotor having a plurality of channels fluidly connecting at least two of the stator ports, the plurality of channels and plurality of stator ports being configured to maintain a first flow path from the pump to a column during a valve transition from a load state to an inject state while establishing a second flow path through the valve between a syringe port and a sample needle port.

2. The rotary shear-seal injection valve of claim 1 further comprising:
a first stator channel for fluidly connecting the pump to the column.

3. The rotary shear-seal injection valve of claim 2 further comprising:
a syringe port channel having a sufficient length to ensure the fluid flow in the sample loop is discharged towards a syringe during valve reversion.

4. The rotary shear-seal injection valve of claim 3 wherein,
at least a second one of said stator ports is in fluid communication with the pump such that, during valve transition from the load state to the inject state, the second stator port becomes fluidly connected to an upstream side of a sample loop and the pump concurrently pressurizes the sample loop and the first flow path.

5. The rotary shear-seal injection valve of claim 2 , wherein:
at least a second one of said stator ports is in fluid communication with the pump such that, during valve transition from the load state to the inject state, the second stator port becomes fluidly connected to an upstream side of a sample loop and the pump concurrently pressurizes the sample loop and the first flow path.

6. The rotary shear-seal injection valve of claim 1 further comprising:
a stator channel extension for fluidly connecting the pump to a sample loop.

7. The rotary shear-seal injection valve of claim 6 further comprising:
a syringe port channel having a sufficient length to ensure the fluid flow in the sample loop is discharged towards a syringe during upon valve reversion.

8. The rotary shear-seal injection valve of claim 7 wherein,
at least a second one of said stator ports is in fluid communication with the pump such that, during valve transition from the load state to the inject state, the second stator port becomes fluidly connected to an upstream side of the sample loop and the pump concurrently pressurizes the sample loop and the first flow path.

9. The rotary shear-seal injection valve of claim 6 wherein,
at least a second one of said stator ports is in fluid communication with the pump such that, during valve transition from the load state to the inject state, the second stator port becomes fluidly connected to an upstream side of the sample loop and the pump concurrently pressurizes the sample loop and the first flow path.

10. The rotary shear-seal injection valve of claim 1 further comprising:
a channel having a length sufficient to ensure the fluid flow in a sample loop is discharged towards a syringe during valve reversion.

11. The rotary shear-seal injection valve of claim 10 wherein,
at least a second one of said stator ports is in fluid communication with the pump such that, during valve transition from the load state to the inject state, the second stator port becomes fluidly connected to an upstream side of the sample loop and the pump concurrently pressurizes the sample loop and the first flow path.

12. The rotary shear-seal injection valve of claim 1 further comprising:
a syringe port channel having a sufficient length to ensure the fluid flow in a sample loop is discharged towards a syringe during valve reversion.

13. The rotary shear-seal injection valve of claim 12 wherein,
at least a second one of said stator ports is in fluid communication with the pump such that, during valve transition from the load state to the inject state, the second stator port becomes fluidly connected to an upstream side of the sample loop and the pump concurrently pressurizes the sample loop and the first flow path.

14. The rotary shear-seal injection valve of claim 1 , wherein:
at least a second one of said stator ports is in fluid communication with the pump such that, during the valve transition from the load state to the inject state, the second stator port becomes fluidly connected to an upstream side of a sample loop and the pump concurrently pressurizes the sample loop and the first flow path.

Assignees

• Waters Technologies Corp

Inventors

• Dourdeville Theodore A
• Keene Russell L
• Ciolkosz Theodore D
• Usowicz James E

Classifications

• F16K11/0853 Primary

  having all the connecting conduits situated in a single plane perpendicular to the axis of the plug · CPC title

• G01N30/20 Primary

  using a sampling valve · CPC title

• G01N2030/202

  rotary valves · CPC title

• G01N2030/201

  multiport valves, i.e. having more than two ports · CPC title

• G01N2030/207

  with metering cavity, e.g. sample loop · CPC title