Patent ID: 6260524
Filing Date: 2001-07-17
Classification: F01L,F02D,Y02T

Abstract:
A valve timing control system for an internal combustion engine, comprising:an intake valve and an exhaust valve driven in synchronism with rotation of said internal combustion engine for opening and closing an intake passage and an exhaust passage, respectively, which are communicated to a combustion chamber of said internal combustion engine;operation state detecting means for detecting operation state of said internal combustion engine;desired valve timing arithmetic means for arithmetically determining a desired valve timing for at least one of said intake valve and said exhaust valve in dependence on said engine operation state as detected;a variable valve timing mechanism for changing open/close timing for at least one of said intake valve and said exhaust valve;actual valve timing detecting means for detecting an actual valve timing of at least one of said intake valve and said exhaust valve;actual valve timing control means for generating a control quantity for said variable valve timing mechanism so that a timing deviation of said actual valve timing from said desired valve timing becomes zero;integral control means for arithmetically determining an integral correcting value by integrating said timing deviation for thereby correcting said control quantity;initializing condition detecting means for detecting as an initializing condition an engine operation state in which said integral correcting value is to be initialized; andinitializing means for initializing said integral correcting value to an optimum value conforming with said engine operation state when said initializing condition is detected,wherein said initializing means is so designed as to set an initial value of said integral correcting value to a negative value.