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:
Feb. 21, 2012
Filed:
Apr. 23, 2008
Shunsuke Toshioka, Susono, JP;
Tomihisa Oda, Numazu, JP;
Takekazu Itoh, Toyota, JP;
Yutaka Tanai, Susono, JP;
Satoshi Watanabe, Sunto-gun, JP;
Yoshitaka Nakamura, Toyota, JP;
Shunsuke Toshioka, Susono, JP;
Tomihisa Oda, Numazu, JP;
Takekazu Itoh, Toyota, JP;
Yutaka Tanai, Susono, JP;
Satoshi Watanabe, Sunto-gun, JP;
Yoshitaka Nakamura, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
In an internal combustion engine, an NOx selective reduction catalyst is arranged in the engine exhaust passage and a urea aqueous solution stored in a urea aqueous solution tank is fed to the NOx selective reduction catalyst where the NOx is selectively reduced. Opening and closing of the urea aqueous solution refill port of the urea aqueous solution tank are detected and it is judged if the urea aqueous solution is refilled in the urea aqueous solution tank. When it is judged that the NOx purification rate has fallen to an allowable level or less at the time of engine operation right after the urea aqueous solution is refilled in the urea aqueous solution tank, it is judged that the refilled urea aqueous solution is abnormal.