Patent ID: 6861646

Claim:
A gas sampling system for an ion mobility spectrometer comprising: a first gas pump providing a first gas flow at a partial gas vacuum compared to ambient gas pressure; a second gas pump providing a second gas flow, different from said first gas flow, at a partial gas pressure compared to the ambient gas pressure; a first orifice in communication with the first gas pump to provide the first gas flow toward the first gas pump, wherein the first gas flow is external to said ion mobility spectrometer; tubulation means connecting said first orifice to said ion mobility spectrometer; a second orifice in communication with said second gas pump to provide said second gas flow that rotates about and substantially surrounds said first gas flow to increase vacuum at a sampling location distal from the first orifice; and gas deflection means for inducing a rotational cyclonic motion of said second gas flow from said second orifice, wherein the gas sampling system samples said first gas flow for analysis in the ion mobility spectrometer.