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:
Dec. 22, 1998
Filed:
Sep. 10, 1996
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
According to the present invention, SO.sub.X in the exhaust gas of an internal combustion engine is absorbed by a sulfate absorbent which absorbs SO.sub.X in the exhaust gas when the temperature is lower than a releasing temperature and releases the absorbed SO.sub.X when the temperature becomes higher than the releasing temperature. When the exhaust gas temperature increases during the operation of the engine and reaches the releasing temperature, the temperature of the exhaust gas flowing into the sulfate absorbent is further raised to a predetermined temperature by supplying fuel to the exhaust gas passage upstream of the sulfate absorbent. The ratio of SO.sub.3 in the SO.sub.X mixture released from the sulfate absorbent changes in accordance with the temperature, and takes the highest value at a certain temperature (i.e., a peak temperature). Therefore, when the exhaust gas temperature is raised above the peak temperature, the ratio of SO.sub.3 in the SO.sub.X mixture released from the sulfate absorbent decreases as the temperature increases. In the present invention, the above-noted predetermined temperature is selected in such a manner that the ratio of SO.sub.3 at this predetermined temperature becomes lower than the ratio of SO.sub.3 at the releasing temperature. Therefore, when SO.sub.X is released from the sulfate absorbent, the amount of SO.sub.3, i.e., the amount of particulate matter released into the atmosphere can be maintained at a low level.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile