Transfer device for the leading end of a film web or a film matrice from a thermoforming machine to a comminuting mill and method for operating the transfer device

摘要

A motor driven transporting carriage (13) moves along guides (12,14) and has clamps to hold the leading end of the film strip (5) or the grid-like residue (10) of a film strip. A pair of powered transporting rolls (29,30) is positioned close to an inlet into a shredder (3) for film recovery. The carriage (13) may be moved by either: a) a motor (21) mounted on the carriage which drives cogs engaging with racks on the guides (12,14); b) by a fixed motor drive which drives endless chains (25) to which the transporting carriage is connected via a chain (27); c) by a drive mounted on the carriage which drives cogs over which toothed belts or roller chains are guided between the outlet from the thermoforming machine and the inlet to the mill. Drive units may be electrically or pneumatically powered and move synchronously with the conveyer (11) of the thermoforming machine. Transporting rolls (29,30) also move synchronously with the conveyer and form pinch rolls with pins, naps, ribs or a rough surface. The position of one roll (30) can be varied through an angle relative to the other. The horizontal guide rails (14) run into vertical guide rails at the transporting roll end. The initial guide rails (12) can be swiveled as a unit or comprise hinged parts movable relative to each other. A sensor on the carriage records the leading end of the film strip (5) and controls clamp closure. A fixed sensor located in front of the carriage records the presence of the latter and stops its movement before initiating clamp opening. An independent claim is included for a process for operating the film transfer machine in which take-up of the leading end of the film strip or grid-like waste film strip is recorded by a sensor, the thermoforming machine conveyer is stopped, the clamp operated to grip the film and over the remaining part of the travel to the transporting rolls the carriage and conveyer move synchronously.