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:
Sep. 17, 1991
Filed:
Sep. 11, 1990
George K Parnoff, Walnut Creek, CA (US);
Andros Incorporated, Berkeley, CA (US);
Abstract
This invention is a filter assembly for preparing gases for an exhaust gas analyzer. A single housing includes at least three filter cavities, an inlet passage and two outlet passages. A coarse filter for filtering particlate matter and for condensate condensation is disposed in the first filter cavity. Condensate from the first cavity drains into the second filter cavity which has disposed therein a fine filter for filtering condensate. An outlet passage is connected to the second filter cavity for withdrawal of the condensate. A fine filter for filtering the exhaust gas is disposable in the third filter cavity which is coupled to the first filter cavity. A second outlet passage connects the third filter cavity to a pump for removal of the gas to be analyzed. The present invention thus provides a multiple filter assembly in a single housing with large fine filter area, minimal void volume, minimal interconnections, and convenient access to the individual filters. This achieves precise filtration of gases for analysis, allows low pump flow rates which save costs, lowers system stress, and reduces response time, minimizes leak potential, saves labor and equipment costs, and protects filters and peripheral equipment.