| 摘要 |
<p>PURPOSE:To make easy the starting, by inserting slidably onto a cam shaft a ring piece that is anchored to a rocker arm by the resiliency of a spring so that the rocker arm may be presed by the ring piece when an engine is started thereby opening an exhaust valve a little. CONSTITUTION:The rotation of the cam shaft 2 rotatably mounted on a cylinder head 1 presses the rocker arm 4 down via a cam 3 to open the exhaust valve 5. The ring piece 6 is slidably mounted on the cam shaft 2, and the spring 2 is located between the ring piece 6 and a circlip 7 thereby anchoring the ring piece 6 onto the upper surface of the rocker arm 4. A fixing ring 10 is anchored on the cam shaft 2 by a spring 9 opposite to the ring piece 6, and the cam shaft 2 is provided with an oil hole 11 open to the inside of the ring piece 6. Thus, when the engine is started, the ring piece 6 is pressed resiliently by the spring 8 to open the exhaust valve 5 a little thereby making the starting easy.</p> |
