Gas diffuser ion inlet

Patent metadata

Field	Value
Publication number	US-9455131-B2
Application number	US-201214369271-A
Country	US
Kind code	B2
Filing date	Nov 28, 2012
Priority date	Dec 28, 2011
Publication date	Sep 27, 2016
Grant date	Sep 27, 2016

Abstract

In some embodiments, a gas diffuser for use in a mass spectrometer is disclosed that can provide a controlled expansion of an ion-containing gas so as to reduce gas velocity for entry into subsequent stages of the mass spectrometer, e.g., a mass analyzer. In some embodiments, the controlled expansion of the gas is provided by flowing the gas through a channel whose cross-sectional area change, e.g. progressively increases, in the direction of the gas flow so as to provide controlled expansion of the gas.

First claim

The invention claimed is:

1. A gas diffuser for use in a mass spectrometer, comprising: an input aperture for receiving a flow of a gas; and a gas flow conduit extending from said input aperture to an exit aperture, said gas flow conduit comprising a first gas flow channel in fluid communication with a second flow channel exhibiting an increasing cross-sectional area in a direction of said exit aperture so as to cause controlled expansion of the gas flow from said input aperture to said exit aperture, wherein said first and second flow channels are formed by a solid core.

2. The gas diffuser of claim 1 , wherein said first channel is configured to provide a substantially annular flow region.

3. The gas diffuser of claim 1 , wherein said input aperture comprises an annular aperture.

4. The gas diffuser of claim 1 , wherein said gas flow conduit comprises a curved outer wall and a curved inner wall.

5. The gas diffuser of claim 3 , wherein said curved inner wall comprises a surface of a solid core positioned in a cavity provided by said outer wall.

6. The gas diffuser of claim 3 , wherein each of said curved inner and outer walls diverges away from a longitudinal axis of the gas diffuser as each of the walls extends from said input aperture to a respective inflection section.

7. The gas diffuser of claim 1 , wherein each of said inner and outer walls converges toward the longitudinal axis of the gas diffuser as each of the walls extends from a respective inflection section to the exit aperture.

Assignees

• Dh Technologies Dev Pte Ltd

Inventors

• Thomson Bruce

Classifications

• H01J49/24

  Vacuum systems, e.g. maintaining desired pressures · CPC title

• B05B1/005

  Nozzles or other outlets specially adapted for discharging one or more gases · CPC title

• H01J49/26

  Mass spectrometers or separator tubes · CPC title

• H01J49/0422 Primary

  for gaseous samples (interfaces to gas chromatographs G01N30/7206) · CPC title

• H01J49/0404

  Capillaries used for transferring samples or ions (electrospray nozzles H01J49/167) · CPC title