摘要 |
<p>The invention relates to a drive mechanism for achieving variable valve timing in an internal combustion engine. A drive crank 69 is coupled to a driven crank 72 by a slotted disc 63 rotatably mounted in a yoke 66 and movable between on-axis and offset positions relative to a common axis of rotation of the two cranks. To control the position of the yoke 66 a force is applied to the yoke to urge the disc away from the on-axis position, the direction of the force being such that the reaction force on the yoke, resulting from the rotation of the slotted disc in an offset position, acts to move the yoke 66 and the disc 63 into the on-axis position as the rotational speed of the disc increases.</p> |