Patent Document ID: 20010006062
Application ID: 09735929
Patent Flag: 0

Claim One:
1. An air-fuel ratio controller for an internal-combustion engine, comprising: an air-fuel ratio detector provided in an exhaust system of the engine for detecting an air-fuel ratio of exhaust gas; means for calculating an A/F ratio feedback coefficient by proportional term control and integration term control; a timer for setting length of time for the integration term to be carried out in accordance with an operating state of the engine; means for calculating said integration term on the basis of time set by said timer; and means for setting the proportional term for shifting the A/F ratio feedback coefficient; a deviation detector for detecting a deviation between a first A/F ratio feedback coefficient before the integration term is carried out and a second A/F ratio feedback coefficient after the integration term is carried out and the coefficient is shifted by the proportional term set by said means for setting the proportional term; and means for correcting, based on the deviation, the length of time for the integration term to be carried out.