Valve timing control device for an internal combustion engine,申请号US19940312586-传众专利搜索

Valve timing control device for an internal combustion engine

申请公布号：US5482012(A)

申请号：US19940312586

申请日期：1994.09.27

申请公布日期：1996.01.09

申请人：

TOYOTA JIDOSHA KABUSHIKI KAISHA

发明人：YOSHIOKA, MAMORU

分类号：F01L13/00;F01L1/344;F02D13/02;F02D41/04;F02D41/06;(IPC1-7):F01L1/34

主分类号：F01L13/00

摘要：A valve timing control device for an internal combustion engine. The device comprises first determination means for determining a first optimal value of the valve overlap period in the current engine operating condition, on the basis of the current engine speed and load, second determination means for determining a second optimal value of the valve overlap period in the current engine operating condition by reducing the first optimal value when the engine has not warmed up, and valve overlap period control means for controlling a valve overlap period using the first optimal value, or such that it varies gradually from the second optimal value to the first optimal value, when the current degree of opening of the throttle valve is larger than a predetermined value, even if the engine has not warmed up. A back-flow of exhaust gas does not occur when the degree of the throttle valve is relatively large so that the valve overlap period at this time is made larger and a higher engine torque can be obtained to increase the trapping efficiency and the scavenging efficiency, even if the engine has not warmed up.