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:
Jul. 17, 2012
Filed:
Dec. 12, 2006
Hiroyuki Hokuto, Numazu, JP;
Hiroyuki Hokuto, Numazu, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, JP;
Abstract
Cylinders of an internal combustion engine are divided into at least two cylinder groups. First air-fuel ratio sensors are disposed in each exhaust branch pipe connected to the cylinder groups, and a second air-fuel ratio sensor is disposed in a common exhaust pipe upstream from the catalyst. When a vapor amount introduced into an intake passage during purge control is determined, the vapor amount is determined during normal operation using output values from the first air-fuel ratio sensors and the vapor amount value learned during normal operation. During rich-lean operation, the vapor amount is determined using the output value from the second air-fuel ratio sensor and the vapor amount value learned during rich-lean operation. Thereby, the vapor amount introduced into the intake passage when a switch is made from normal to rich-lean operation of the internal combustion engine is accurately determined.