Patent ID: 7770558
Filing Date: 2010-08-10
Classification: F02D,Y02T

Abstract:
1. An intake air control system for an internal combustion engine comprising at least one intake valve and a valve operating characteristic varying mechanism which continuously varies a lift amount of said at least one intake valve, said intake air control system comprising: idling condition determining means for determining an idling condition of said engine; target intake air flow rate calculating means for calculating a target intake air flow rate of said engine; lift amount command value calculating means for calculating a command value of the lift amount of said at least one intake valve according to a target engine rotational speed set in the idling condition of said engine and the target intake air flow rate when said engine is determined to be in the idling condition; lift amount control means for controlling said valve operating characteristic varying mechanism according to the calculated lift amount command value; and external load detecting means for detecting an application and a removal of an external load on said engine, wherein said lift amount command value calculating means increases or decreases the lift amount command value with a limited rate of change in the lift amount command value when the application or the removal of the external load is detected.