Patent ID: 6718939
Filing Date: 2004-04-13
Classification: F02D,Y02T

Abstract:
An engine cylinder induction air quantity measuring apparatus for an engine provided with a valve overlap period during which an intake valve and an exhaust valve both open, the engine cylinder induction air quantity measuring apparatus comprising:an intake air quantity sensing section to sense an intake air quantity of air drawn into an intake system of the engine; an intake manifold inside air quantity calculating section to calculate an intake manifold inside air quantity of air in an intake manifold of the engine, from the intake air quantity by performing a balance calculation to calculate a balance between an intake manifold inflow air quantity of air flowing into the intake manifold, and an intake manifold outflow air quantity of air flowing out of the intake manifold; a cylinder induction air quantity calculating section to calculate a cylinder induction air quantity of air inducted into a cylinder section of the engine in accordance with the intake manifold inside air quantity; an engine stop position determining section to detect an engine stop of the engine, and to determine whether an engine stop position of the engine is within the valve overlap period; and a manifold inside air quantity modifying section to set the intake manifold inside air quantity equal to an overlap stop mode final air quantity and thereby to cause the intake manifold air quantity calculating section to use the overlap stop mode final air quantity as an initial value of the intake manifold inside air quantity in a next start of the engine when the engine stop position is within the valve overlap period.