Patent ID: 6276316
Filing Date: 2001-08-21
Classification: F01L,F02D,Y02T

Abstract:
An intake-air quantity control apparatus for an internal combustion engine, comprising:an intake-valve actuator that actuates an intake valve; anda control unit configured to be electronically connected to the intake-valve actuator, the control unit comprisinga first section that calculates a target intake air quantity on the basis of an engine operating condition,a second section that calculates both an intake valve closure timing on an intake stroke and an intake valve closure timing on a compression stroke on the basis of the target intake-air quantity,a third section that calculates a crank angle corresponding to a minimum valve operating time period of the actuator from an intake valve open timing to an intake valve closure timing on the basis of an engine speed,a fourth section that compares the crank angle corresponding to the minimum valve operating time period of the actuator with a crank angle corresponding to the target intake air quantity from an intake valve open timing to an intake valve closure timing on the intake stroke,a fifth section that selects the intake valve closure timing on the intake stroke when the crank angle corresponding to the minimum valve operating time period of the actuator is less than the crank angle corresponding to the target intake air quantity, and selects the intake valve closure timing on the compression stroke when the crank angle corresponding to the minimum valve operating time period of the actuator is greater than or equal to the crank angle corresponding to the target intake air quantity, anda sixth section that outputs a control signal representing the intake valve closure timing selected by the fifth section to the actuator.