Cam 1 rotates about fixed axis A. Follower 2 reciprocates in fixed guides B-B and carries rollers 3 and 4. Roller 3 can be adjusted to various positions along follower 2 by screw device a. In the position shown, the follower stroke has i ts maximum value x_max. By changing the position of roller 3, the stroke of the follower can be varied within the limits from x_min to x_max. Working surface b of cam 1 acts alternately on rollers 3 and 4. The rollers are held in contact with the cam by special springs (not shown). Impacts occur when lobe b of the cam comes into contact with the rollers.
$3144$SmC,LL$