Alan L French

US Patent:

6598461, Jul 29, 2003

Filed:

Oct 29, 2001

Appl. No.:

10/000245

Inventors:

Trenton M. Hering - Corvallis OR
Alan L. French - McMinnville OR
Calvin B. Lofton - Lebanon OR

Assignee:

Hewlett-Packard Development Company, L.P. - Houston TX

International Classification:

G01N 100

US Classification:

73 2341, 73 2342, 73 6155, 7386312, 347 19

Abstract:

An inlet system is used in conjunction with a standard gas chromatograph/mass spectrometer to facilitate the analysis of volatile components of substances fired from inkjet pens. The system allows for the investigation of changes in the ink resulting from resistor firing. In addition, the system can be used as a diagnostic tool to detect failures in individual firing chamber. After a block is cooled with liquid nitrogen, an analyte sample of ink is deposited on a stage in a chamber in the block and the chamber is then sealed. The stage is then heated vaporizing a portion of the analyte sample. A transfer gas passes over the stage and mixes with vaporized analyte. The mixture then enters a gas chromatography mass spectrometer which determines the analyte samples components and relative amounts thereof.