VARIABLE VALVE SYSTEM FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To realize more accurate valve characteristic control by reducing a moving amount detection error of a cam shaft caused by a difference of thermal expansion coefficients. SOLUTION: This variable valve system comprises a cam shaft 22 having three-dimensional cams 25 supported rotatably and slidably in an axial direction relating to a cylinder head 6 to continuously change a cam profile along the axial direction, hydraulic actuator 30 moving the cam shaft 22 in its axial line direction, and a cam shaft moving amount detection part 50 having a cam shaft position sensor 51 provided in the cylinder head 6 and a detected part 52 provided in the cam shaft 22 to detect a moving amount in the axial line direction of the cam shaft 22. Here, the cam shaft moving amount detection part 50 is provided in the vicinity of a cam shaft reference position (position regulating movement in an axial direction of the cam shaft 22) P0.