US 7,363,801 B2
Gas chromatograph sample injector
Hitoshi Tsuchihashi, Osaka (Japan); Akihiro Miki, Kyoto (Japan); Munehiro Katagi, Osaka (Japan); Mayumi Nishikawa, Osaka (Japan); and Kei Zaitsu, Nara (Japan)
Assigned to Shimadzu Corporation, Kyoto (Japan)
Filed on Dec. 20, 2005, as Appl. No. 11/311,263.
Claims priority of application No. 2005-299479 (JP), filed on Oct. 14, 2005.
Prior Publication US 2007/0084302 A1, Apr. 19, 2007
Int. Cl. G01N 30/02 (2006.01)
U.S. Cl. 73—23.41  [422/89] 6 Claims
OG exemplary drawing
 
1. A sample injector for injecting a liquid sample into a sample-vaporizing chamber located at an inlet of a column of a gas chromatograph, which is used to analyze a sample that needs to undergo a derivation process before an analysis, the sample injector comprising:
a) a liquid-holding device having a syringe with a needle attached to its tip and a plunger slidably inserted into the syringe;
b) an actuator for activating the plunger; and
c) a controller for controlling the actuator to push or pull the plunger so that:
a derivation reagent is suctioned into the syringe, whereafter a sample to be analyzed is suctioned so that the sample is held closer to the needle and the derivation reagent farther from the needle;
the needle is inserted into the sample-vaporizing chamber; and
the plunger is pushed into the syringe in a manner so that the sample held in the syringe is first injected into the sample-vaporizing chamber, and then the derivation reagent held in the syringe is injected into the sample-vaporizing chamber when a predetermined period of time has elapsed after the injection of the sample into the sample-vaporizing chamber.