摘要 |
A drive mechanism for advancing workpieces through a plurality of spaced-apart work stations which are arranged so that the distances between certain adjacent work stations are greater than the distances between other adjacent work stations. During an advancing stroke, the drive mechanism moves each workpiece from one work station the entire distance to the next work station so that no workpiece occupies any space between adjacent work stations after the completion of the advancing stroke. The drive mechanism includes a rotary drive crank to which a plurality of drive links are pivotally mounted. Each drive link is connected to a transfer bar which is guidably supported for straight line reciprocal movement to engage and advance the workpieces. A predetermined half-cycle movement of the drive crank imparts contemporaneous movement to the transfer bars which are moved through different distances during the half cycle movement of the drive crank to advance all workpieces to the next work stations. |