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:
May. 06, 1997
Filed:
Dec. 29, 1995
David R Sheridan, Menlo Park, CA (US);
Glenn C Morrison, Berkeley, CA (US);
Gas Research Institute, Chicago, IL (US);
Abstract
A gas sampling system and method that utilizes a double aspirator design to precisely control the flow rate of a gas sample past a sensor (44, 46, or 48). The double aspirator design includes a primary aspirator (24) to draw a gas sample from the exhaust stack (14) at a first flow rate and a secondary aspirator (26) to draw a portion of the gas sample from the primary aspirator at a second flow rate past the sensors. In addition, a first pressure sensor (74) and second pressure sensor (76) are provided in order to monitor changes in the pressure differential across the sensor so that corresponding changes in the second flow rate can be accounted for by the control unit (18) when processing the measurement data from the sensor.