摘要 |
<p>This invention relates to an automatic release mechanism for a cultivator which provides good resistance to release of the shank holder and which upon release causes the shank holder to rise to a good height to clear obstacles encountered during operation of the cultivator. The shank holder is mounted so as to pivot about an axis and is retained in the working position by a pair of springs under tension, the forward end of the springs being mounted in front of and beneath the position of the pivot axis of the shank holder, and the moment arm of the springs is such that, as the shank holder pivots, the moment arm decreases resulting in the tangential force applied by the springs to the ground engaging tool about the pivot axis remaining substantially constant during pivoting of the shank holder to clear an obstacle.</p> |