| 摘要 |
<p>PURPOSE:To make rapid changeover of the characteristic of a valve system by disengaging a select pin which is advanced/retracted by means of hydraulic pressure applied thereto, from a cam which is displaceably installed, on a cam shaft, in its radial direction, and enabling the feed of oil through a communicating passage to an engaging part. CONSTITUTION:In the cam shaft 1 of a multiple valve type engine, a cam fitting part 6 with a nearly rectangular cross section and a pin installing part 5 are formed in the axial direction on the outside of the cams 2, 2 for low speed formed integratedly with the cam shaft 1, and a cam 3 for high speed is installed inside the annular groove- shaped engaging recess part 12 formed on the cam engaging part 6. And the cam 3 for high speed is so constructed as being pushed upward against a spring 43 by cooperation of hydraulic pressure force exerted on a piston part 35 with engaging force of the select pin 41 in a lock mechanism 40, when pressure of oil introduced from an oil passage 7 to a pressure chamber 21 side is high. On the other hand, an introducing passage 9 for communicating the pressure chamber 20 at the end of the select pin 41 with an oil passage 7, and a position facing to the top end of the select pin 41 of a pin fitting hole 16, are communicated with each other through a communicating passage 13.</p> |
