EP0138160A2 - Plactic foil winder with flying web roll replacement - Google Patents

Abstract

Two pairs of spooling roll bearings are mounted on a rotary disc pair (61), the rotation of which causes in each case one pair, together with a spooling roll (9), to be brought into the winding position. In this position, the web (1) is fed by means of a contact roller (30), which is pivotably mounted below the spooling roll (9), to the spooling roll (9) from the side on which the pivot point (60) of the rotary disc (61) is situated. Mounted on the other side is a cutting device (50a, b) which can be swung in from above, so that the cutting edge (54), at the top between the spooling roll (9) and the contact roller (30), comes into cutting position when a full reel (11) is further rotated into the removal position. <IMAGE>

Description

The invention relates to a reel for plastic film with at least two reel rolls, which are interchangeably mounted on both ends in two turntables at the same distance from their pivot bearings, which are mounted in the side walls of a frame and are connected to separately controllable drives, and in which the turntables are connected to another controllable drive are connected and in which a pressure roller of the length of the reel rollers is mounted parallel to these and in such a way that it can be rotated at both ends so that the film, which over it with a wrap angle of approximately 180 °, respectively the reel roller in the working position or the respective one located thereon Winding is fed, is applied with a predetermined train.

Reels are known in which a roll is created on a reel, while the previously completed roll is removed from the device and replaced by an empty reel. For this purpose, the two reel rollers are rotatably mounted in motorized drives in parallel turntables and, as soon as a winding is completed, the turntable is rotated further by 180 °, so that the empty reel comes into working position and the full reel can be removed. The film is then suddenly cut with a separating knife, and the resulting beginning is placed around the free reel roll.

So that the film is wound tightly, it is constantly fed under tension to the roll via a pressure roll with a 180 ° wrap, and the pressure roll exerts a predetermined pressure on the roll. For this purpose, it is mounted on a controlled slide which is pushed from the side onto the roller in the working position. Such a parallel slide guide and the associated parallel feed drive of the pressure roller is very expensive because it is due to the low thickness of the film of z. B. 20 um and the width of the web of several meters must be very accurate.

It is an object of the invention to disclose a substantial simplification of the storage and the drive of the pressure roller.

The solution to the problem is that the pressure roller is mounted in a swivel arm, which is mounted below the turntables in swivel bearings in the frame, and a deflection cylinder is rotatably mounted between the swivel bearings, around which the incoming film is guided onto the pressure roller.

In the known reels, the coils lie next to one another in the working or changing position, and the filled coil is exchanged in the changing position via the semicircular path below. In contrast, the full bobbin is exchanged on the upper semicircular path, which means that the fulcrum of the turntables can be lower by the distance of the winding axis, since the full winding is not rotated under it. This advantageously results in a reduction in the overall height of the device.

So that the empty bobbin can be exchanged on the lower path, when the reel is fully wound, the pressure roller is pivoted so far away that the empty bobbin runs in the direction of rotation next to the pressure roller when the turntables continue to rotate. During the swiveling movement and the subsequent swiveling back into the working position, which takes place evenly as the full roll continues to rotate, the length of the free, not yet wound film web remains practically unchanged at constant winding speed and constant film feed, which advantageously results in the formation of firm, wrinkle-free windings, in particular of the crucial starting positions.

To facilitate the bobbin changing process, it is known to pivot an automatically operating cutting device onto the film web after the bobbin exchange so that the new beginning of the film arises between the empty bobbin and the pressure roller during cutting and falls smoothly into it. For this purpose, the knife and other clamping cylinders were swiveled together from below between the full reel and the empty spool and swung over them in order to get into the correct cutting position. The path of the film web was disadvantageously extended, which resulted in distortion of the film or a controlled braking of the full roll during the swiveling in of the cutting device was required. In addition, it was necessary to choose the distance between the full reel and the empty spool and corresponding to the bearings in the turntables so that the cutting device could be pivoted between them, which in turn required a larger overall arrangement and a stronger drive on the turntables. These disadvantages are avoided by a new arrangement of the cutting device, which is inventive in itself and in particular in connection with the lower pivot bearing of the pressure roller and the exchange of the wrap on the upper track, and consists in that the cutting device about a pivot axis which is approximately laterally one full winding is in the working position, is pivotally mounted and is connected to a drive ', which can be pivoted from an approximately vertical rest position from above to the side in the approximately horizontal cutting position. The tensioning cylinder, which is in front of the knife in the direction of film travel, then lies opposite the pressure roller next to the empty spool, and the other tensioning cylinder lies on the film behind the knife with slight pressure. A film web extension advantageously does not occur. The center distance of the coils is reduced and the turntables and the overall device are reduced accordingly.

The slight differences in the free web length that occur when the bobbin is exchanged are advantageously compensated for in that the cutting device and thus the tensioning cylinder is swung into the film web with slight pressure already during the bobbin exchange and gradually moves into the cutting position.

Another advantageous embodiment of the swivel arm of the pressure roller as a two-part arm with counterweight stabilization and sensitive auxiliary drive is described in the description with reference to the figures.

The use of a pressure roller with internal cooling and drive by the cooling water is an advantageous further development of the device, since the cooling of the film immediately before the winding prevents shrinkage in the roll and the turbine-like drive of the roll delivers a uniform pull of the film and none other than the cooling water hoses pivoting, requiring compensation, drive means are required.

An exemplary embodiment is shown in FIGS. 1 to 3, in which all advantageous features are contained. The replacement of individual modules by other known or a displacement of the pivot axes, in particular the cutting device with a corresponding design of the swivel arm, so that the working positions of the components involved in the respective functions are the same to one another is possible without leaving the principle of the inventions.

As far as similar arrangements, e.g. B. with three coils, such a geometry of the arrangement of the modules can not be easily achieved, in which the free film web length hardly changes, so can be created by a suitable choice of the gear of the coil drive compensation in relation to a specific coil diameter by an associated rotation is transferred from the turntable rotation to the spool.

• Fig. 1 shows schematically a cross section through a reel in the position before cutting;
• 2 shows a plan view of the reel of FIG. 1,
• 3 shows a special embodiment of the swivel arm of the pressure roller on a larger scale,
• Fig. 4 shows a transmission for a coil drive schematically.

1 shows a base frame 19 which carries two vertical parallel side cheeks 20 at a distance of several meters, between which the coils 9, 10 for windings 12, 11 of the film 1 and the pressure roller 30, the deflection cylinder 34 and the knife 54 and the clamping cylinder 51, 52 of the cutting device 50 extend parallel to one another.

In the side walls, turntables 61 are symmetrically mounted for the coil exchange in bearings 60 and connected to a controllable synchronous rotary drive. In these turntables 61, the coils 9, 10 are interchangeably supported at a distance A from the bearing 60, so that one full coil 11 can be brought into the change position, removed there and replaced by an empty one, when the other is wound, without interruption the film is fed when the bobbin is replaced.

Furthermore, swivel arms 31, which carry a pressure roller 30 and whose swivel bearings 33 are located below the turntable 61, are supported on the frame 19 or the side cheeks 20 on both sides of the winding. A deflection cylinder 34 lies between the pivot bearings.

The swivel arm 31 is swiveled against the frame 19 via a drive 36 which can be controlled hydraulically. If an empty spool 9 is in the working position, the swivel arm is approximately vertically upward, and the pressure roller 30 lies approximately centrally on the winding from the side from which the spool was swung in. If the winding becomes fuller, the pressure roller 30 swings out to the side and downwards up to the coil size 12 v. The film 1 is fed from below the deflecting cylinder 34 and wraps around the pressure roller by approximately 180 ° and then passes onto the spool with the reverse curvature. This results in a uniform pull in the tangential direction and a pressure at the point of contact, which avoids air pockets.

If the winding 12 v is full, the swivel drive 36 is relieved or vice versa, so that the pressure roller 30 comes into such a laterally lower position 30b that an empty spool 10, which has meanwhile been inserted, turns the right turn of the turntable above the pressure roller 30 on path 71 happens. As soon as this has been done, the swivel arms 31 swivel back again, the pressure roller 30 coming into contact with the empty spool. Overall, the turntables 61 are rotated through 180 °, so that the full bobbin comes into position 11, as shown. The film web is deflected around the empty spool. As soon as the film is cut through the knife 54 above the gap between the spool 9 and the pressure roller 30, the new beginning is wrapped around the spool and the full spool can be exchanged.

Only during the last revolutions the pressure roller is not in contact with the winding; but the film 1 is always under tension, since the free length hardly changes when swiveling the swivel arms 31 and when rotating the turntable 61, since the swivel axis 33 is near the surface line of the full winding 12 v and also by half the rotation of the Turntable 61 of the full reel undergoes an additional rotation about its coil axis when moving from position 12 v to position 11, as will be explained further below. The pressure roller can be carried and guided in a known manner in such a way that there is no lengthening of the film web during turning.

An automatic cutting device is also provided for the automatic bobbin change. This is mounted in pivot bearings 57 on the side cheeks 20 with two pivot arms 50, between which the clamping cylinders 51, 52 and the knife 54 are located. The swivel arms 50 can via a swivel drive 58 from an almost vertical position 50b, in which the Spannzy Linder 51, 52 and the knife outside the path 70 of the full spool 12 v when the turntable 61 is rotated are brought into the horizontal working position 50a, in which the knife 54 is located above the gap between the empty spool 9 and the pressure roller 30 and the tensioning cylinder 52, which lies in front of the knife 54 in the film running direction, lies against the empty spool 9 on the opposite side to the pressure roller and the tensioning cylinder 51, which lies behind the knife 54 in the film running direction, on the film 1 between the full roll 11 and the empty spool 9 rests with slight pressure. The knife 54 is connected to a further swivel arm 53 and, via a knife drive 55, to the swivel arm 50 and is actuated suddenly in a known manner when the film is to be separated. The cutting device is advantageously pivoted in from the point in time at which the outermost surface line of the full roll 12 v has passed the connecting line of the pressure cylinder 52 with the rotary bearing 60 when the turntable 61 rotated on the web 70. The pressure cylinder (s) 51, 52 then hold the film under additional tension as it rotates further. After the cutting process, the cutting device is pivoted back again. To increase the cutting force, a counter holder can be arranged above the pressure roller.

From Fig. 2 further details can be seen in the plan, the position of the cutting device is shown before cutting. The swivel arms and drives are covered by the panels of the side cheeks 20; they are constructed in a manner known to the person skilled in the art.

3 shows an advantageous embodiment of the swivel arm 31 and the mounting of the pressure roller 30 and their pressure means. The swivel arm 31 is via a hydraulic swivel Drive 36 connected to the frame 19 through which the pressure roller 30 is brought approximately into the required position. The pressure roller 30 is supported in the first pair of swivel arms 31 in bearings 32, but balanced by counterweights 39, in a second pair of swivel arms 38.

The position of the two pairs of swivel arms 31, 38 relative to one another is determined by a position detector M and reported to a control device, and the swivel drive 36 is actuated by the control device such that a predetermined relative position of the swivel arms 31, 38 is held in each case. Between the swivel arms 31, 38 there is also a controllable drive 40 which, for. B. is a pneumatic drive, via which a certain pressure force is transmitted to the pressure roller 30 with which the winding is compressed. Only when the pressure roller 30 is swung out to allow a new empty spool to pass through is no pressure exerted on the drive 40.

As a further innovation it is provided to provide the pressure roller 30 with cooling water connections 41 and to equip them in the internal configuration in a known manner with a turbine drive which drives in the film running direction in such a way that the film is continuously wound with a certain, very low tension.

The cooling of the film immediately before winding up has the advantage, among other things, that the film, which has already passed cooling rollers before entering the reel, especially if the films are thicker, has a heated surface due to heat transport from the inside, and this heat is almost completely dissipated during the high looping of approx. 180 °.

In Fig. 4, the drive of one of the coils is shown and shown that an additional rotation can be added to the coil drive by suitable choice of the translation of the toothed belt pulleys from the rotation of the turntable.

The toothed belt pulley 90 is rotated by a drive M1 (not shown) in accordance with the desired spool rotation speed. This rotation is transmitted to the toothed belt pulley 95 and thus to the spool 9 via the toothed belt 91, the synchronously coupled gear pair 92, 93 and the further toothed belt 94. The number of teeth is the same for discs 90 and 95 or 92 and 93, provided no further reduction or reduction is desired. The gear pair 92, 93 is mounted on the axis of rotation of the turntable and the wheel 95 with the coil axis on the turntable 61 itself. When the turntable 61 rotates through the drive D (not shown), the coil maintains its rotational speed through the drive Mfbei, if the number of teeth on all discs is the same.

On the other hand, if the gear pair 92, 93 has a relatively small number of teeth, an additional rotation is accordingly transmitted to the spool or vice versa with a relatively larger number of teeth. For a certain coil diameter, e.g. B. that of the coil 12 v, a complete compensation of the free film web length can thus be achieved if, when the turntable 61 is rotated by 180 °, the coil is additionally rotated by 90 °. This is achieved with a tooth ratio of 2: 1 for the disks 95 to 92.

A corresponding drive mechanism is provided for the second coil.

Claims (7)

1. reel for plastic film (1) with at least two reel rollers (9, 10), which are at both ends in two turntables (61) at the same distance (A) from their rotary bearings (62), which are in the side cheeks (20) of a frame (19) are stored, are interchangeably mounted and are connected to separately controllable drives and in which the turntables (61) are connected to a further controllable drive and in which a pressure roller (30) of the length of the reel rollers (9, 10) parallel to these and is mounted so that it can be rotated at both ends so that the film (1), which is fed via this with a wrap angle of approximately 180 ° to the reel roller (9) in the working position or the respective reel (12) located thereon, with a predetermined train is applied, characterized in that the pressure roller (30) is mounted in a swivel arm (31) which is mounted below the turntables (61) in swivel bearings (33) in the frame (19), and between the swivel bearings (33 ) a deflection cylinder (34) is rotatably mounted, around which the incoming film (1) is guided onto the pressure roller (30). 2. Device according to claim 1, characterized in that the bearing (33) of the swivel arm (31) is in the vicinity of the surface line of a full roll (12 v) in the winding position and the swivel arm (31) in contact with an empty winding approximately stands vertically and when the reel is full to let an empty reel roll (9) run in by a swivel drive (36) which is arranged between the swivel arm (31) and the frame (19), the pressure roller (30) to outside the web (71), which lies on a semicircle running downwards, the empty reel roller (9) is pivoted. 3. Apparatus according to claim 1 or 2, characterized in that the double distance (A) of the bearings of the reel rollers (9, 10) from the bearing (60) of the turntable (61) is slightly larger than the radius of an empty reel roller (9 ), the diameter of the pressure roller (30) and the radius of a full roll (11) are together. 4. Device according to one of the preceding claims, characterized in that laterally above the reel roller (9) in the working position, a cutting device (50, 50a, 50b) on the side cheeks (20) is pivotably arranged, the knife edge (54) of which in the working position (54a ) lies approximately above the gap between the empty reel roller (9) and the pressure roller (30) and, in the swiveled-out position (50b), with all the components (51, 52, 54) extending between the pair of swivel arms (50) from the rotating range (70 ), which the generatrix of the full roll (12 v) passes through when the turntable (61) rotates, is pivotable, and the pivot drive (58) is preferably a pneumatically or hydraulically controlled cylinder which is located between the pivot arms (50) and the side cheeks (20) are arranged. 5. Apparatus according to claim 4, characterized in that between the pair of swivel arms clamping cylinders (51, 52) are rotatably mounted, of which the one which lies in the running direction of the film (1) in front of the knife (54) in the working position (50a) next to the empty reel roller (9) on the opposite side as the pressure roller (30) comes to rest and the other lies on the film web (1) in the running direction behind the knife (54). 6. Device according to one of claims 1 to 3, characterized in that the pressure roller (30) in the swivel arm pair (31) with a further swivel arm pair (38) is mounted in bearings (32) and the weight of the pressure roller (30) with respect to Bearing (32) is balanced by counterweights (39) and the swivel arms (38) by a force transmitter (40), preferably pneumatically controlled pistons, emit a moment against the swivel arms (31) that corresponds to the pressure moment of the swivel roller (30) on the reel (12) corresponds, and the drives (36) of the swivel arms (31) are controlled so that the swivel arms (38) and (31) each have a predetermined position to each other. 7. The device according to claim 1, characterized in that the pressure roller (30) is a coolant, for. B. cooling water, and the coolant preferably drives a turbine drive in the pressure roller (30) so that the film (1) is wound with a predetermined tension on the winding (12).

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