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:
Jun. 28, 1983
Filed:
Jul. 31, 1981
James W Butler, Dearborn Heights, MI (US);
Alex D Colvin, Oak Park, MI (US);
Ford Motor Company, Dearborn, MI (US);
Abstract
A method is disclosed for measuring the air to fuel ratio of an air/fuel mixture being supplied to a combustion process. This method has the following steps. An oxygen sensor station is established at which the sensor senses the difference in oxygen partial pressure from a first reference side thereof to a second oxygen measurement side thereof. The oxygen sensor is maintained at a predetermined temperature and at a pressure below atmospheric pressure. The oxygen sensor is calibrated so that the measurement thereby of an EMF between the first reference side thereof and the second oxygen measurement side thereof is indicative of the oxygen partial pressure in a gas stream passing by the oxygen measurement side thereof. A sample gas stream is drawn into the pressure across the second oxygen measurement side of the oxygen sensor. This pressure is one which allows samples to be drawn at a constant flow rate independent of that pressure. A fixed amount of oxygen is added to the sample gas stream. The oxygen in the sample gas stream is reacted with oxidizable species contained in the sample gas stream prior to passing the sample gas stream across the second oxygen measurement side of the oxygen sensor. The pressure of the gas sample is measured. The air to fuel ratio of the air/fuel mixture is determined from the measured EMF of the oxygen sensor, the total pressure of the sample gas stream and the known oxygen addition rate. Suitable oxygen sensors may be formed zirconia or titania.