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. 24, 2013
Filed:
Apr. 23, 2010
Koichi Kitaura, Odawara, JP;
Takahiko Fujiwara, Susono, JP;
Yuuji Miyoshi, Susono, JP;
Ryota Onoe, Susono, JP;
Koichi Kitaura, Odawara, JP;
Takahiko Fujiwara, Susono, JP;
Yuuji Miyoshi, Susono, JP;
Ryota Onoe, Susono, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, Aichi-ken, JP;
Abstract
Active air-fuel ratio control is performed to alternately control an air-fuel ratio in an area located upstream of a catalyst between a lean side and a rich side. Switching is carried out between lean control and rich control at the same time when an output from a post-catalyst sensor reaches a threshold. Whether the catalyst is normal or abnormal is determined based on the rate of a change in the output from the post-catalyst sensor between a first point of time when a pre-catalyst air-fuel ratio reaches stoichiometry after the output from the post-catalyst sensor reaches the threshold and a second point of time when the output from the post-catalyst sensor reaches the threshold next time.