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:
Nov. 18, 2003
Filed:
Jun. 19, 2001
David George Farmer, Plymouth, MI (US);
Gopichandra Surnilla, West Bloomfield, MI (US);
Ford Global Technologies, LLC, Dearborn, MI (US);
Abstract
A vehicle exhaust treatment system includes an emission control device featuring at least one upstream NO -storing “brick,” and a downstream NO -storing “brick” that is substantially smaller in nominal capacity than the upstream brick. An oxygen sensor positioned between the upstream and downstream bricks generates an output signal representing the concentration of oxygen in the device. A controller selects a rich operating condition to purge the device of stored NO , and deselects the rich, NO -purging engine operating condition in response to the sensor output signal, preferably after an additional time delay calculated to provide sufficient excess hydrocarbons to release substantially all stored NO from the downstream brick.