GAS CHROMATOGRAPH AND STRUCTURE FOR SUPPLY FLOW PASSAGE OF CARRIER GAS FOR CHROMATOGRAPH

摘要

PROBLEM TO BE SOLVED: To obtain a gas chromatograph which does not require a rubber and a block which fix a resistance tube by forming a constricted part in a part of a flow passage inside a flow passage assembly so as to be used as a resistance part in the flow passage and providing a pressure measuring means on the upstream side from it. ;SOLUTION: A space formed by a cutout which is formed on a metal plate 22 in a sheetlike flow passage assembly 20 and by corresponding places of metal plates 21, 23 is used as a flow passage 5. A constricted part is formed in a part of the flow passage so as to be used as a resistance part 24. A carrier gas from a supply cylinder 10 reaches a valve 8 via an entrance 4 and the flow passage 5. In a state that the carrier gas flows in the flow passage 5, a pressure according to a flow rate is generated by the resistance part 24 in a pressure sensor 7. A control part 9 adjusts the opening of the valve 8 so that the detection pressure of the pressure sensor 7 becomes a pressure corresponding to a desired flow rate according to the relationship between a pressure stored in an inside memory and the flow rate. As a result, a sample which is introduced by a sample introduction part 15 is carried to an analytical column 16 and a detector 17 together with the carrier gas whose flow rate is controlled, and it is separated and detected. Consequently, a rubber and a block which fix the resistance tube 24 are not required.;COPYRIGHT: (C)1999,JPO