Ignition timing control apparatus for internal combustion engine

Abstract

An ignition timing control apparatus for an internal combustion engine is provided which is capable of preventing the generation of knocking immediately after an intake air control valve is driven to operate. An intake air control valve (23) is provided in an intake passage (5) of an engine (1). A swirl control element (10) controls the opening and closing of the intake air control valve in accordance with operating conditions of the engine thereby to adjust a magnitude of an intake air swirl. An ignition timing calculating element (10) determines ignition timing of the engine through interpolation using ignition timing map data corresponding to the number of revolutions per unit time of the engine and an engine load. A map data setting element (10) switches and sets the ignition timing map data in accordance with opening and closing of the intake air control valve (23). An ignition timing retarding element (10) corrects the ignition timing by a prescribed retarded angle amount over a first predetermined period after a switching of the ignition timing map data.

Dependencies are inferred from the claim text.