SLITTING AND REWINDING MACHINE

Abstract: A cutting-rewinding machine (16) consists of a plurality of reels (1), placed on spokes (2) with motor (3), which rotate in logic sequence each time a coil (9) of cut strips (4′) is formed on one of them. In contact with the reel (1), on which the coil (9) is form­ ing, a peripheral winding roller (8) is present, to which are coupled the accompanying rollers (13) and (14) which wind the tails of the strips (4′) and make then adhere to the multiple coil (9) just formed and the heads of the fol­ lowing strips (4′) to the reel (1′) on which the new coil must be wound, the moment a blade (15) cuts the same strips. In addition, the machine is equipped with a group of spread­ ing rollers, coupled either to said peripheral winding rol­ ler (8) or to the reel (1′) while waiting to receive the winding of new coil (9), while a previous coil (9) is be­ ing wound.

Description: The invention relates to a slitting and rewinding machine, for the manufacture of paper tapes and the like. The machine, is particularly suited to be inserted in a continuous processing train. Present slitting and rewinding machines, used for the preparation of tapes of paper, plastics material or other material, commonly are equipped with multi-blade cutting rollers under which sheet material from a load coil located upstream, passes downstream of the cutting rollers, and is wound, in the form of strips, into finished coils. In these machines, the finished coils of material are removed when the outside diameter of the finished coil reaches a maximum permitted diameter as related to the width of the coiled strip. Each time a finished coil of cut strip material reaches that maximum diameter, it is necessary to stop the machines, sever the strips, secure the trailing cut ends to their associated finished coils, discharge the finished coils, load a new core for the next coils and connect the leading ends of the strips to the newly loaded core. Even if the sheet material to be cut can be supplied continuously the machines must be kept idle for fairly long periods of time. Another condition detectable in the present plants is that, trademarks, signs, decorations, addresses, information drawings or other printed indicia are present on the cut strips. This printing operation is at present carried out preceding or following the cutting of the sheet material. This requires further steps unwinding and rewinding of the sheet material or cut strip, with consequent losses in time in the loading, discharge and connection of the ends of the strips of the sheet material to another core. A machine for the continuous winding of a foil web on a core tube is known by DE-A-3033765. The foil web winding machine discloses by this reference a multi-spindle head rotated between a winding station and a removal station. The winding station has a web winding device and a independently operated cross-cutter between which the web is tensioned via a pivoted deflection roller. The cross-cutter is moved in a straight path when a fully wound reel is positioned at the removal station and an empty reel is positioned at the winding station. The machine disclosed by DE-A-3033765 is not suitable for using in winding foil strips which easily break when submitted to tension. The present invention provides a slitting and rewinding machine for the continuous production of coils of strip material from a continuous sheet of material, which does not present the above-reported drawbacks. The slitting and rewinding machine of the present invention comprises: a rotatable axle provided with motor means for indexing said axle; spokes extending radially of said axle at positions spaced axially of said axle and for the support of cores; and a sub-assembly comprising tensioning rollers, multi-bladed cutting roller, a motorized feed roller for continuously feeding of the cut strips of the sheet material to cores to form coils, and cutting unit comprising a blade moved towards and away from the cut strips; and adhesive application unit; wherein said sub-assembly is moved in a direction to bring the driven feed roller into a continuous frictional driving engagement with the selected core or coil in winding. Particular embodiments of the slitting and rewinding machine of the present invention are set out in dependent claims 2 to 5. The advantages obtained by the slitting and rewinding machine of the present invention are: the cutting of the ends of the slit strips and the replacement of the finished coils by an empty core proceeds automatically without having to stop the machine; the finished coils can be discharged from the machine while the machine is in full production and without any loss of time; the slitting and rewinding machine can be inserted into a production line which includes a complete printing step which precedes the steps of slitting the sheet material into strips and rewinding into coils. The advantages of this invention are that ,the replacement of finished coils wound from the cut strips, the securement of the ends of the finished wound coils, the securement of the ends of the strips to be wound, the cutting of the ends of the strips and the insertion of replacement cores, all take place quickly and automatically with notable gains in productivity. Another advantage consists in the fact that the sequential coupling of the unwinder, the slitter and the rewinder makes it possible to further reduce production time, in this manner increasing productivity while providing products of excellent quality. The invention is now described with reference to the accompanying drawings, in which: fig. 1 shows in detail the basic operating diagram of the slitting and rewinding machine, figs. 2 to 6 show in sequence the steps of winding a finished coil; displacement of the wound coil, alignment of a replacement core; cutting of the strips; and securement of the cut ends of the strips; fig. 7 shows a diagramatic side view of the slitting and rewinding machine when coupled to a printing machine and an unwinder, and figs. 8 and 11 show an alternative embodiment of the machine. As shown in fig. 1, a replacement core (1) is supported at its end by a spoke (2) carried by a motorized axle (3), which is mounted for rotation in fixed bearings and which is indexed through determined angles of rotation by a conventional indexing motor M. The continuous sheet of sheet material is guided and maintained taut by rollers (5) and (6), and passes under a multi-bladed cutting roller (7), of known type, which cuts sheet material into strips (4'). The strips (4') then pass around a motorized roller (8), and are wound onto a core (1) into a plurality of coils (9) arranged axially of the core (1). The coil in formation (9) is therefore formed by a plurality of parallel strips or tapes wound on a single core. For clarity of description, the coil (9) is now referred to as a multiple coil (9). As shown in Figures 2 and 3, When the multiple coil (9) has reached its required diameter, the motorized axle (3) is indexed through a determined angle by the indexing motor M, thus moving the multiple coil (9) arcuately counterclockwise and out of alignment with the the motorized feed roller (8). At the same time, rollers (10) approach the motorized roller (8) and transfer a suitable adhesive from a tray (11) and spread it on the strips (4') entrained around the motorized feed roller (8). A sub-assembly comprises of the guide rollers (5-6), the motorized feed roller (8), the cutting roller (7), the adhesive transfer rollers (10), and a cutting unit (13,14,15), described later, is mounted for movement towards and away from a core (1) presented thereto, and is biassed towards the motorized axle (3) by any conventional biassing means. The sub-assembly is shown in Figure 2 in a retracted position relative to the motorized axle (3), which has been caused by the progressively increasing radius of the coil (9). An shown in Figure 4, the entire sub assembly then moves under the influence of the biassing means towards a replacement core (1'), which has at that time moved into alignment with the motorized feed roller (8), until such time that the feed roller (8) comes into contact with the core (1'). On this contact, the adhesively coated tapes or strips (4') are compressed between the feed roller (8) and the core (1'), and become adherent to that core (1') which then commences to rotate by the friction drive from the motorized feed roller (8). Referring now to Fig. 5, the cutting change, unit (13,14,15) then approaches the strips (4') to bring a roller (13) into contact with the formed multiple coil (9) and another roller (14) into contact with the replacement core (1') as shown in Figure 5; the cutting change unit being supported and moved by any convenient know means. At this point, (fig. 6), the blade (15) cuts all of the strips (4'), while the roller (13) moves into contact with the multiple coil (9), to adhere the cut ends of strips to that multiple coil (9). At the same time the roller (14) moves into contact with the core (1') to adhere the other ends of the strips (4') to that core (1'). When the operation is complete, the adhesive application unit (10) - (11) and the cutting change unit (13,14,15) return to their initial positions and the slitting and winding steps resumes at normal speed. According to a second embodiment shown in Figures 8 to 11, the adhesive application unit (10) and (11) can be placed in alignment with core (1') at a position in advance of the motorized feed roller (8) and that core (1') is employed to transfer adhesive to the strips (4'). During the winding step of the coil (9), the replacement core (1') is in contact with roller (10) and it is coated by the adhesive. When the coil (9) has reached its required diameter, the motorized axle (3) again is indexed, moving the finished coil (9) by one angular position of the motorized axle (3). The sub-assembly (5-15) moves towards the motorized axle (3) to bring the motorized feed roller (8) into engagement with the adhesively coated replacement core (1'), and the tapes or strips (4') into contact with core (1') coated with adhesive. The cutting change unit (15), (13), (14) approaches the strips (4') to bring the roller (13) into contact with the coil (9) and the roller (14) into contact with the new replacement core. At this point, the blade (15) cuts all of the strips (4'), while the roller (13) slides in contact with the formed coil (9), to adhere the cut ends of the strips to that coil; while the roller (14) adheres the other ends of the strips (4') to the core (1'). During these steps, another core (1) is aligned to the glue transfer rollers (10) and is covered with a layer of adhesive. All the above operations are automatically controlled in sequence by a microprocessor, which also controls mechanisms which lock the new cores ready for winding, and releases those of the finished multiple coils (9). This provides a fully automatic, robotized system. By use of the invention, it is therefore possible to continuously carry out the removal operations of the finished multiple coils (9) and the installation of new cores to be wound, thus eliminating time during which the machine is inoperative. Obviously, if sheet material already coated with a layer of self-adhesive material are to be cut and wound, the devices (10,11) for applying the adhesive can be eliminated. With reference to figure 7, the cutting-rewinding machine (16) is incorporated into a continuous processing train including a printing station (17) supplied by an unwinding unit (18). The unwinding unit (18) includes at least two continuous coils (19). The coils (19) are so positioned that, when one is unwinding, the other can be prepared for unwinding, and viceversa. In the unwinding sequence, the end of a coil on completion of unwinding is locked by a piston (28) and rethreaded by means of a through-blade through a slit (29), after which the end of the following coil is also locked by a piston (30) and rethreaded with the same blade, in the same way as the end of the previous coil. The sides of the top and tail of the two coils are thus flanked and rethreaded in the same way, making their union, by means of adhesive tape, easy and rapid. In particular, to make connection of the coils safer and more effective, the sides are rethreaded in an oblique line; in this way, the sides are more extended and need a larger quantity of adhesive tape or similar. Although each remains in its own supporting seat, the continuous strips (4) are thus unwound and sent by the coils (19), following a route of guide rollers (20), tension rollers (21) and pressure rollers (22), to the printing station (17). In said station, the continuous strips (4) are made pass between the press-roller (23) and printing roller (24), then conveyed along a drying route (25), supported by guide rollers (26). Subsequently, by means of a plurality of conveyor rollers (27), the continuous strips (4) are sent to the slitting and rewinding machine (16) according to the present invention and are subjected to slitting and rewinding operations to provide multiple coils (9), as described in detail above. The continuous processing train, comprising an unwinding unit (18), a printing station (17) and a slitting and rewinding machine (16) permits the production of printed strips or tapes in decidedly shorter times than possible with the present techniques.

Claims: A slitting and rewinding machine for the continuous production of coils of strip material from a continuous sheet of material (4), said machine comprising: a rotatable axle (3) provided with motor means (M) for indexing said axle; spokes (2) extending radially of said axle (3) at positions spaced axially of said axle and for the support of cores (1); and a sub-assembly comprising tensioning rollers (5, 6), multi-bladed cutting roller (7), a motorized feed roller (8) for continuously feeding of the cut strips (4') of the sheet material (4) to cores (1) to form coils (9), and a cutting unit comprising a blade moved towards and away from the cut strips (4'); and an adhesive application unit (10,11); wherein said sub-assembly is moved in a direction to bring the driven feed roller (8) into a continuous frictional driving engagement with the selected core (1) or coil (9) in winding. The slitting and rewinding machine according to claim 1, characterized in that the cutting unit is positioned between the core (1) and the feed roller (8) and it comprises a first roller (13) and a second roller (14) moved in directions to bring into contact respectively with the formed coil (9) and the replacement core (1"). The slitting and rewinding machine according to claim 1 or 2, characterized in that the adhesive application unit (10, 11) is a part of the sub-assembly and is moved towards and away from the cut strips (4'). The slitting and rewinding machine according to anyone of the preceding claims wherein the adhesive application unit (10, 11) is in alignment with the feed roller (8). The slitting and rewinding machine according to anyone of the preceding claims from 1 to 3, characterized in that it the adhesive application unit (10, 11) is arranged in alignment with the replacement core (1').

Inventors: NEGRUSSI, LUIGI
Applicants: FIN STELLA S.R.L.
Application year: 1988
Main classification: B65H19
IPC codes: B65H19