| 摘要 |
<p>PURPOSE: To obtain a valve lifting characteristic suitable for an operation condition and prevent occurrence of partial abrasion of engagement groove surfaces with which pins are in contact. CONSTITUTION: A cylindrical cam shaft 22 is arranged on an outer periphery of a driving shaft 21 rotated synchronously to an engine, while a annular disc 29 is arranged between a flange 27 of the cam shaft 22 and a flange 32 of a sleeve 28 connected and fixed to the driving shaft 21. The annular disc 29 is held by means of an oscillatable control ring 35, and a pair of pins 36, 37 engaged with engagement grooves 30, 33 of the flanges 27, 32 are rotatably attached thereto. The annular disc 29 is oscillatingly controlled by means of a driving mechanism according to an engine operation condition. The control range is regulated so as not to cause a concentrical state with the cam shaft 22, so that the pins 36, 37 are always slid.</p> |
