| 摘要 |
PURPOSE:To change the opening amount of the valve by changing the pivot point of rocker arm by providing a rack in the base end of the rocker arm which pushes the valve at its other end to open it, and by moving a pivot gear, which is meshed with the rack, in proportion to the engine speed. CONSTITUTION:As a solenoid valve 15 remains closed in a low engine speed range via an engine speed sensor 16, a hydraulic plunger 9 does not protrude, and a pivot gear 5 stays in a retracted position by a spring 8. That is, the pivot gear 5 moves the pivot point of the rocker arm 3 away from a cam 18, as it is meshed with the rack formed on the underside of the base end of the rocker arm 3. Therefore, as the camshaft 17 rotates, the rocker arm 3 rocks in a smaller stroke to cause an intake or exhaust valve 4 to open by a small amount. On the other hand, in a higher speed range, the solenoid valve 15 is opened, and the pivot gear 5 is moved forward by the hydraulic plunger 9. As a result, the pivot point of the rocker arm 3 moves closer to the cam 18, and the opening amount of the valve 1 becomes larger. |
