| 摘要 |
<p>PURPOSE:To change the lift amount of a valve by switching the position of a cam to a cam projection position and a cam retreat position without increasing the mass of a rotary operating part and complicating the structure of the part. CONSTITUTION:A high speed cam 8 is supported rotatably in one body with a can shaft 5, and movably in its radial direction on the cam shaft 5, and a valve lift amount is changed by moving the high speed cam 8 in its radial direction. A cylindrical surface 11a is provided on the high speed cam 8, and arranged on a circumference concentrically with the rotary axial core of the cam shaft 5 in a condition in which the high speed cam 8 is moved to the projection position in the radial direction. A switch driving mechanism 18 is provided outside the cam shaft 5 independently from the cam shaft 5. The switching driving mechanism 18 is directed in lift direction of a valve in relation to the cylindrical surface 11a, and abuts displaceably to a position opposing to the projection position and the retreat position of the high speed cam 8, and also, at least, being allowed to be maintained at a position opposing to the projection position of the high speed cam 8.</p> |
