Device for qualifying products containing volatile substances

Device to qualify products containing volatile substances forming together an analyte, comprising a measuring apparatus (2) with a measuring enclosure (21a) and an analysis electronic circuit (21b) to define the characteristics of said analyte, a pumping system (30) to make a vacuum inside said enclosure (21a), a sampling chamber (16) into which said analyte is introduced and a capillary (22) to connect said chamber (16) to said enclosure (21a), said chamber (16) comprising:

• a first inlet (18) to introduce said analyte and fitted with a gastight cap (27;
• 60, 62),
• a second inlet (17) connected to a source of purge gas (11) and fitted with a valve (23), and,
• an outlet (19) allowing the exhaust of the gas contained in said chamber (16) and also fitted with a valve (29),
• the device comprising furthermore a transfer system (35, 32, 63, 64) to introduce the analyte into the sampling chamber, and a command programmer (15) for the analysis circuit (21b), for the transfer system (35, 32, 63, 64) and those valves (23, 29), allowing to achieve sequentially the purge of the chamber, of the capillary and of the enclosure, then the introduction of the analyte into the enclosure, and, finally, its analysis, the device being characterized by the fact that the programmer (15) is set up in such a way that:
• in a first phase (51, 52), the valves of the second inlet (23) and the outlet (29) are open to let the purge gas go through, as long as a significant number of analyte particles previously analyzed may remain in the chamber (16), the enclosure (21a) or the capillary (22),
• in a second phase (53), the inlet valve (23) is closed, preventing the penetration of the purge gas,
• in a third phase (54), the transfer system (35, 32, 63, 64) is activated, to introduce the analyte to measure into the chamber (16),
• in a fourth phase (55), the outlet valve (29) is closed,
• in a fifth phase (56), at least, the analysis apparatus (2) defines the characteristics of the analyte passing from said chamber (16) into the enclosure (21a), and
• in a sixth phase (57), the operation starts again at the first phase, as long as there are still other products to qualify.