Patent ID: 8671903
Filing Date: 2014-03-18
Classification: F02N

Abstract:
1. An engine stop and start control system having an automatic stop and start function of automatically stopping an engine when a preset automatic stop condition is met, and of performing cranking by a starter when a preset engine restart condition is met to restart the engine, the engine stop and start control system comprising: an engagement control means that shifts a pinion of the starter to a ring gear coupled to an output shaft of the engine to perform engagement between the pinion and the ring gear during the engine coasting after the automatic stop of the engine; a rotation control means that rotates the pinion using a rotational drive means when the engine restart condition is met; an engagement determining means that determines whether the engagement by the engagement control means is completed or the pinion has been shifted to a contact position of the ring gear so that the pinion is in abutment with the ring gear; and a state determining means that determines, based on a speed of the engine or a parameter associated with the speed of the engine, whether the engagement is completed or the pinion is in abutment with the ring gear during reverse rotation of the output shaft of the engine, wherein: when the engine restart condition is met after the engagement by the engagement control means is started and before it is determined that the engagement by the engagement control means is completed or the pinion is shifted to the contact position of the ring gear so that the pinion is in abutment with the ring gear, the rotation control means disables rotational drive of the pinion by the rotational drive means during a period until it is determined that the engagement by the engagement control means is completed or the pinion is shifted to the contact position of the ring gear so that the pinion is in abutment with the ring gear, the rotation control means determines the period when it is determined that the engagement is completed or the pinion is in abutment with the ring gear during reverse rotation of the output shaft of the engine, and the state determining means determines whether the engagement is completed or the pinion is in abutment with the ring gear during reverse rotation of the output shaft of the engine based on a reduction rate of the speed of the engine.