The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 07, 1998
Filed:
Oct. 08, 1996
Robert E Uber, Allison Park, PA (US);
Viktor Kouznetsov, Mars, PA (US);
Alexander Tarassov, Mars, PA (US);
Byron L Carnahan, Pittsburgh, PA (US);
Charles W Pipich, Monroeville, PA (US);
Mine Safety Appliances Company, Pittsburgh, PA (US);
Abstract
Generally, the present invention provides a recirculating filtration system for use with a transportable ion mobility spectrometer in gas chromatography applications. The transportable recirculating filtration system comprises a pump and a set of filters and flow sensors connected to an ion mobility spectrometry sensor having a gas chromatograph column at its inlet. The IMS sensor's outlet flow is cleaned by the filters and recirculated by the pump back into the IMS sensor as the carrier fluid stream flow. A portion of the IMS sensor's outlet flow equal to the amount of flow introduced into the sensor as the sample is exhausted from the filtration system to maintain a constant total flow volume through the system as the sample is being analyzed. Preferably, the multicapillary column is sealed to a heated transfer line leading to the sample stream inlet of the IMS sensor. The transfer line is preferably maintained at a temperature 10.degree. C.-40.degree. C. above that of the multicapillary column in order to ensure that analyte species will not adsorb on the walls of the transfer line instead of entering the sample stream inlet of the IMS sensor. The transfer line can be optionally configured with a flow smoothing insert to produce a laminar flow profile throughout the volume between the transfer line outlet end and the IMS sensor housing upon exit of the carrier flow stream from the flow smoothing insert.