Nissan Motor Company Limited

Eri Imai

Masaki Koga

Tsuyoshi Ishikawa

Yoshiyuki Ootake

Tomoya Mori

An engine idle speed control device set a target idle speed NsetN for a non-traveling range is set to a high value to activate the catalytic converter early, after the engine is started. Upon detecting that the automatic transmission has been shifted from a non-traveling range to a traveling range, the target idle speed is lowered to a first traveling idle speed Nset. A feedback gain G used for feedback control of the ignition timing is then set to a larger gain value. The larger gain value is set such that it varies based on the temperature of the automatic transmission fluid or other parameter indicative of the engine friction and/or automatic transmission friction. As a result, the ignition timing is retarded in a precise manner, the engine speed is reduced, and the clutch engagement shock is reduced.

Engine idle speed control device

An engine idle speed control device set a target idle speed NsetN for a non-traveling range is set to a high value to activate the catalytic converter early, after the engine is started. Upon detecting that the automatic transmission has been shifted from a non-traveling range to a traveling range, the target idle speed is lowered to a first traveling idle speed Nsetfor a prescribed period (200 ms). After the prescribed period elapses, the target idle speed is lowered even further to a second traveling target idle speed Nset. When the target idle speed is set to the first traveling target idle speed Nset, the ignition timing retardation amount RET is set in accordance with the actual engine rotational speed Ne in such a fashion that the higher the engine rotational speed Ne is, the more the ignition timing ADV is retarded.

Growing community of inventors

Chigasaki, Japan

Eri Imai