Controlled rate linear motion drive

摘要

This relates to a drive mechanism of the rack and pinion type wherein the length of the rack is less than the required travel and there are plural drive pinions which singly and then sequentially engage the rack. The drive pinions may be driven in any manner, but when a variation in speed is desired in addition to reciprocation, it has been found that a cam type drive will provide the desired mechanical movement. The rack may be beneficially used to effect the controlled movement of a shirred casing strand along a mandrel.