Hydromechanical plastic web indexing system for synthetic plastics thermoforming machinery

摘要

An indexing system for synthetic plastics molding machinery, wherein plastic web gripping drive elements are employed to feed a plastic web in planar indexing movements to the molds of the machine, utilizes a conventional pump driven hydraulic motor connected with the web gripping drive elements by drive transmission mechanism incorporating a brake for positively halting the web gripping elements in predetermined position. A stroke measuring control device driven by the drive transmission mechanism in a path of movement corresponding with the indexing moving of the web gripping elements first decelerates the movement of the web gripping elements and then positively halts them in a predetermined position. Alternatively, a photoelectric eye sensitive to the position of the web can stop the web.