DEVICE FOR PNEUMATIC METERING OF SAMPLES FOR VAPOR-PHASE GAS-CHROMATOGRAPHIC ANALYSIS Russian patent published in 1995 - IPC

FIELD: analysis of materials. SUBSTANCE: device has three-cell metering cock 1 coupled to chromatographic column 2, metering space 3, needle 4 of sample-taking unit, line 5 to supply gas medium and head (or blow-through)line 6. Needle of sample-taking unit moves by means of pneumatic gear 11 between extreme positions of its end in atmosphere and vapor space of vessel 12. Head line 6 has three-way cock coupled to source 7 of gas head through valve 8 and discharge pneumatic resistance 9. Feeding and discharge of gas are conducted in line without resistance, equilibrium in vessel is established when needle is taken out of it which increases authenticity of measurements and enables design of gas circuit to be simplified. Independent movement of needle allows reverse blow-through to be conducted into vessel first which eliminates harmful effluent. EFFECT: enhanced authenticity of measurements, simplified design of gas circuit. 3 dwg