摘要 |
<p>A sickle drive has a sway bar that is coupled with the sickle to reciprocate the latter during oscillation of the sway bar. The latter is operably coupled with a crank drive through a special linkage employing a pair of oppositely extending, short pitman links that compensate for one another adjacent opposite ends of the sickle stroke to vary the velocity of the sickle substantially sinusoidally. The oppositely directed inertia forces of the sickle adjacent opposite ends of its stroke, made equal by the special linkage, are balanced out by a pair of superimposed, oppositely rotating weights driven in timed relationship to reciprocation of the sickle, thereby presenting a substantially vibration-free drive.</p> |