GB1535724A - Apparatus and method for dispensing sheets of wrapping material - Google Patents

Abstract

1535724 Dispensing sheets from continuous roll G E LETT 19 Nov 1975 [20 Nov 1974 25 July 1975] 50397/74 and 31328/75 Heading B8M [Also in Division B4] A web of unperforated plastics material in the form of a roll 8 has its free end passed over a roller 6 having a blade movable relative to the roller to perforate the web and then over a severing means 17 so that on pulling the free end of the web a line of perforations extending across the web is formed at intervals along the length of the web and the web is severed at each line of perforations as the line passes severing means 17 to give a sheet of wrapping material. As disclosed the perforating roller 6 has a longitudinal slot 19a, Fig. 9, in its periphery 19 and a rectangular frame of sides 22a, 22b carrying a row of perforating spikes 24 fixed to one long side of the frame. The cylinder and frame rotate together about fixed shaft 25. Cams 28 fixed to shaft 25 are pressed against the side of the frame carrying perforating spikes 24 by a bowed spring 29 fixed to the opposite side of the frame. The cams cause the row of spikes 24 to emerge from slot 19a once in each revolution of roll 6. There may be more than one slot through which a row of perforating points emerges in each revolution of roll 6. Guide rollers 10, 11 are provided to ensure that the web passes around a substantial part of the circumference of roll 6. Roll 11 rotates about shaft 12 in slots 13 and can be removed to facilitate threading the web around the rollers to produce the path shown in Fig. 4 by swinging back pivoted trunnion 14. Preferably the web roll, of cling film or polythene wound on a cardboard former 9, is rested on roller 6 and a support roller 7 which is braked by tensioner spring 18. The tapered severing means 17 projects away from the perforating apparatus so that the free end of the web may be conveniently grasped. A work-table 16 facilitates wrapping. It may be heated to seal the wrapped package or a hot plate may be provided. Two perforating rolls (6A, 6B, Figs. 12-14, not shown) of different diameter and/or having a different number of perforating means may be mounted on either side of roll 8 so that sheets of different length may be obtained. Longitudinal movement of roll 8 may be prevented by means of two abutment members (60, Figs. 15-16, not shown) each comprising a conical part (61) and a flange part (62) which fits into an end of former 9 so that the conical part touches the respective side wall 2 of the dispenser. Reference has been directed by the Comptroller to Specification 1482193.