EP0468842A1 - Method for cutting and dispensing multi-width printed webs and positioning device to carry out this method - Google Patents

Abstract

In the extension of a feed table (5) is provided a positioning table (1) which is itself equipped with endless belts (19), each carrying a catching gripper (20), for drawing an initial web coming from the feed table onto itself, devices for locating and positioning the web being provided at least at the entrance and exit of the positioning table. The invention is used for the production of wide-width printed webs. <IMAGE>

Description

The invention which lies in the technical field of cutting and gluing of strips to produce printed wide webs, relates more precisely to the cutting and distribution process and the positioning device for the implementation of the process.

It is known that the bands printed, for example transfer papers on which patterns or drawings appear, are used to print very wide bands.

The printing machines used up to now allow the printing of strips of paper generally up to two meters in width, which appears sufficient. However, it has become obvious that it is not possible with such tapes to produce larger tapes without building printing machines for this purpose for strips of four to five meters in width, which is difficult to envisage. from an economic point of view. We then know the solution which consists in using the strips of conventional size and assembling and gluing them to form a wide strip suitable for printing a larger surface. For this purpose, an initial strip carrying designs or patterns is brought side by side with another strip or with an assembly of these strips already adjusted, which is again adjusted using a marking of the relative positions of said strips. , so that the designs and patterns coincide perfectly and so that the strips can then be glued after adjustment.

A machine is known for implementing such a method comprising an inlet conveyor means bringing an initial strip perpendicular to outlet conveyor means conveying the strip which is formed using sections of the initial strip , the conveyor means being arranged to position each section using the locating means relative to the end of the belt on the conveyor.

The marking means in question consist of a plurality of marking impressions of rectangular shape arranged on the unprinted edges of the strip. The wide web is obtained from strip sections which are successively held in place by positioning clips. Numerous photoelectric sensors corresponding to the location prints control motors which move the positioning clamps so that each section is perfectly adjusted with respect to the previous one. All this leads to a relatively complex machine, the development and adjustment of which prove to be very delicate. In addition, the need to mark the marking prints on the side of the strips complicates its manufacture. Finally, it has been found that with such a machine, the strip section is not perfectly supported over its entire surface by the mobile support which moves it and can take in air at the expense of its good positioning.

These drawbacks have led the Applicant to imagine and develop a particular system which very significantly improves the previously known machine, in that it clearly simplifies the operation of locking and positioning the strip sections, and in that it eliminates the creation of any particular impression of location on the printed tape.

The invention guarantees the production of a perfect fitting of the design and perfect continuity in industrial production, regardless of the number of glued joints. The unwinding and winding of the bands is controlled by precise numbers and constants contained in the drawing, and the bands do not interfere with each other.

A first object of the present invention therefore relates to a process for the production of a continuously printed design with a width greater than the initial width, by successively cutting and assembling sections of initial strip whose length corresponds to the width of the wide strip. , method according to which the cutting is ensured, the successive assembly of the strip sections by the lateral edges of the length of the initial strips, and the winding of the new strip assembled using these individual sections, under the control and the control of a plurality of sensors which detect the geometry of the design of the initial strip and / or of corresponding marks. The strip is cut longitudinally before assembly to remove an unprinted selvedge and this cut is made in connection with the design.

According to another main characteristic of the invention, the unwinding of the initial strip is controlled by a servo-control and by counting of passages of reference marks under a sensor and the speed of the servo-control is slowed down after detection of the passage of the 'penultimate mark forming a mark so as to stop the latter mark exactly at the predetermined location.

Advantageously, the end of the initial strip is gripped by hooking means which have, with respect to the servo speed, a slight advance so that the strip is pulled with a slight tension.

According to another particular characteristic of the invention, the winding of the wide web is controlled by signals emitted by the sensors which detect the geometry of the design of the initial web and / or of corresponding marks.

Another main object of the invention consists in a device for positioning, cutting and distributing initial strips, with a view to the formation of wide strips according to which a positioning device which is itself equipped is provided in the extension of a feeding table means for pulling an initial strip coming from the feed table and immobilizing it, and according to which devices for locating and positioning the strip are provided at least at the entrance and at the exit of the positioning device.

According to a particular embodiment of the invention, the means for pulling an initial strip coming from the feed table consist of endless belts forming part of the positioning device and each equipped with a hooking clamp, the opening is ensured by a corresponding jack, said jacks being mounted at the apex of each belt, on a movable spacer extending transversely above a positioning table, as well as on a fixed transverse beam.

Advantageously, the endless belts move in longitudinal notches of the positioning table, by being flush with the level of said table or by disappearing below against in the notches.

According to a preferred embodiment, the attachment clip consists of a base fixed to the endless belt and a central rocker articulated on said base, which ends in a pinch plate maintained in abutment on the belt by a spring.

According to another particular characteristic of the invention, the devices for locating the strip consist of a first photoelectric cell disposed at the outlet of the feed table and of a second photoelectric cell located at the level of the displaceable spacer, the second cell activating the first cell when the strip comes close to the spacer, and putting the unwinder of the feed table at idle.

• Figure 1 une vue schématique en perspective d'une table de positionnement, de découpe et de distribution de bandes imprimées.
• Figures 2 et 3 des vues en plan et en coupe d'une pièce d'accrochage.
• Figures 4 et 5 des vues schématiques en élévation d'une pince d'accrochage en position ouverte et en position fermée.
• Figure 6 une vue schématique simplifiée en plan de l'ensemble de la machine.
• Figures 7 et 8, respectivement des vues schématiques simplifiées en élévation de côté et en bout de ladite machine.

Other particular characteristics and advantages of the invention will appear on reading the following description of an embodiment taken by way of nonlimiting example, and in which reference is made to the appended drawings which represent:

• Figure 1 a schematic perspective view of a table for positioning, cutting and distributing printed webs.
• Figures 2 and 3 are plan and sectional views of a fastening piece.
• Figures 4 and 5 schematic elevation views of a fastening clamp in the open position and in the closed position.
• Figure 6 a simplified schematic plan view of the entire machine.
• Figures 7 and 8, respectively simplified schematic views in side elevation and end of said machine.

The positioning and cutting table shown in perspective in Figure 1, in plan in Figure 6 and in section in Figure 7, is designated as a whole by the reference 1. It comes as an extension of a tape unwinder 2 printed from a feed roller 3. The original tape is pulled by drive rollers 34 (Figure 7). The speed of the drive rollers 34 is controlled by photosensors. The position of a compensating cylinder 32 controls the unwinding of the printed web of the roll 3. The unwinding device also contains a means of lateral control of the web illustrated by the arrow 33 (FIG. 6) which allows the printed web to be conducted in exact and constant relationship (i.e. without lateral offset on table 1).

The printed web moves flat on a feed table 5 located at the same level as the positioning table 1.

A series of applicator rollers 6 mounted on the same transverse cross member 7 hold the strip applied against the table. At the border between the feed table and the positioning table deploys a tube 8 carrying a movable knife 4 capable of cutting a strip immobilized on the positioning table. In this zone at the outlet of the table there is also a photoelectric cell 9. The positioning table 1 extends over a length greater than the maximum desired width of wide web. The table is lined longitudinally with beams forming edges 10 serving to support a movable spacer 11 which extends transversely like a bridge above the table. The distance of the spacer from the feed table corresponds to the width of the desired wide width.

The position of the spacer is therefore adjusted accordingly. The latter carries a photoelectric cell 12, oriented downwards, to detect the presence of a sheet. Finally, a fixed transverse beam 31 is located just at the entrance to the table 1, at a level slightly higher than its plane between the two banks 10. One of the longitudinal banks 10 is disposed slightly above the plane of the positioning table 1 , to allow the lateral release of a wide web towards an exit reel 16. Plumb with the edge 10 the table is provided with a lateral longitudinal groove 13 surmounted by a horizontal gluing bar 14 extending over the entire length of the table, which bar being capable of being applied to the table under the action of jacks 15. At the entrance to the positioning table 1, above the groove 13 is fixed a distributor of glue 17. The fixed positioning table 1 is provided in addition to a plurality of longitudinal indentations 18, occupied by endless belts 19 which have the possibility of being flush with the level of the table, but also of being erased below in the indentations.

Whatever its position, at the table or obliterated in the notch, each belt 19 has the possibility of moving longitudinally, in one direction or the other, under the action of mechanisms not shown. The belts have the function of pulling a strip from the feed table 5 to place it on the positioning table 1. For this purpose each belt 19 is equipped with a hooking clip designated as a whole by the reference 20. A clamp shown in more detail in FIGS. 2 and 3 consists of a base 21 fixed laterally to the belt by a set of screw-nut 22 and a central rocker 23 articulated on the base 21 by a horizontal shaft 24 One end of the rocker ends in a pinch plate 25, the opposite end being in the form of a cam 26. The rocker is returned by a spring 27 in the position shown for which the plate 25 is strongly supported on the belt 19 and for which the cam 26 is obviously in the high position. The zone 30 located between the pivot shaft 24 of the clamp 20 and the cam 26 therefore in the central zone of the rocker is advantageously profiled to receive the end of a rod 28 of a jack 29 mounted vertically vertically of each belt 19. We see in Figure 4 a clamp 20 in the closed position that is to say with its plate 25 resting on the belt 19 and in Figure 5 the same clamp in the open position due to the action of the rod 28 of the jack 29 on the zone 30 of the rocker 23.

The jacks 29 are therefore arranged vertically above each belt, on the one hand on the displaceable spacer 11 and on the other hand on the transverse beam 31. The space of the table 1 between the spacer and the beam corresponds to the dimension of the wide width strip sought.

The belts 19 move there so that each clamp 20 can travel only the distance separating the spacer from the beam according to an operating process which will be described below.

Before the assembly / gluing process, the printed strip must be cut on an edge at a fixed distance from the drawing so that the unprinted selvedge is eliminated, so that this edge can be glued without interrupting the drawing (in connection) . During this procedure, care must be taken to ensure that appropriate means, for example by monitoring and controlling the exact position of marker marks with photocells, ensure the conditions mentioned. This section of the selvedge can also be integrated by a person skilled in the art into the assembly device.

An initial printed strip coming from the unwinder 2 is brought to the feed table 5 at the edge of the positioning table 1, passing under the transverse cross member 7 which holds it thanks to the applicator rollers 6. The unwinding of the initial strip coming from the feed table 5 undergoes a lateral movement controlled by a photoelectric cell 39. The end of the initial strip comes to rest under the beam 31 after being engaged under the plate 25 of each of the clamps 20 carried by said beam. Then the jacks 29 are released and the strip is kept attached to the belt 19 by the clamps.

The belts then move in the direction of the spacer 11 and attract the previously immobilized strip on the positioning table.

During this movement, the dispenser 17 continuously deposited a strip of glue on the edge of the strip.

The web control regulates the speed of the web according to a predetermined program. The photocell 9 counts the number of connections using the unrolled reference marks.

After counting the passage of the penultimate marker mark, the servo speed is continuously reduced, so that the last marker mark is exactly at the place predetermined by the photocell 12 or 9 which defines the final position of the sheet after counting and slowing down. At the start and during the unwinding of the strip, the clamps 20 grip the strip at the level of the cutting device 8.

The advancement of the clamps 20 is controlled in relation to the control of the strip so that the clamps 20 have a slight advance towards the end of the strip and in this way hold it in slight tension.

The clamps 20 hold the strip with the possibility of sliding so that the slaving of the strip controls the final position of the strip and not the progress of the clamps. This unwinding arrangement guarantees, in conjunction with the means mentioned below, that the tape runs smoothly.

As soon as the strip detected by photocel-Iule 9 or 12 has reached the final position, the device 6 or 34 or both hold the sheet to be cut by the device 4 and 8. It is then in the correct position to be glued. The device 38 is lowered and then the pressure device 14 is actuated for the chosen period of time and is then lifted because the jacks 29 of the spacer have come into action to open the corresponding clamps. At this moment begins the winding of the wide strip over the pulling cylinder, while the belts 19 are erased in the corresponding notches 18.

During the lateral release phase of the wide web, the belts 19 return to their initial position to bring the clamps back to the level of the beam 31. Since this movement takes place while the belts are removed in the notches 18, the clamps do not can hang the tape. As soon as the belts are therefore immobilized in good place, the jacks 29 of the beam 31 come into action to open the clamps 20 then close them again to clamp a new strip and the cycle resumes.

It will be noted that the wide web therefore emerges laterally and is wound on the outlet winder 16.

So that the winding occurs regularly and without wrinkles over the entire width (up to 5 m), this new wide strip is pulled over a cylinder 35. Pressers 36 are supported by equal forces (for example by pneumatic cylinders) on the cylinder 35 and thus ensure the regular advancement of the entire strip as shown in FIG. 8.

Carrier cylinders 37 of the outlet winder also have a slight circumferential speed advance towards that of the cylinder 35 and thus ensure the regular winding of the strip. As the width of the original strip (for example in paper) can vary and with this the printed design (for example under the influence of humidity), the means described ensure that the assembly takes place correctly by observing the winding condition controlled by a constant contained in the drawing.

So that the wide strip already wound does not stick or brake (the result will be a cross position of the sheet on the table) prematurely with the strip which is in progress, the primer is raised over the entire width of 1 - 2 cm by means of a table 38. This table 38 descends shortly before the lowering of the pressure device 14.

After this step, the work cycle can start again. Practical experience has shown that maintaining these principles ensures that the inevitable geometric variations of the printed design do not accumulate during production (assembly) and thus lead to an imprecise fitting (or a gradual shift of the design) but on the contrary, as the process is controlled by the drawing itself, the perfect connection is ensured even during large production films.

Claims (20)

1. Process for the production of a continuously printed design with a width greater than the initial width, by successively cutting and assembling sections of initial strip whose length corresponds to the width of the wide width strip, characterized in that it consists of ensuring the cutting, the successive assembly of the strip sections by the lateral edges of the length of the initial strips, and the winding of the new strip assembled using these individual sections, under the command and control of a plurality of sensors which detect the geometry of the design of the initial strip and / or corresponding marks 2. Method according to Claim 1 characterized in that the strip is cut longitudinally before assembly to remove an unprinted selvedge and in that this cut is made in connection with the drawing. 3. Method according to claim 1 characterized in that the unwinding of the initial strip is controlled by a servo and by counting the passage of reference marks under a sensor and by the fact that the speed of the servo is slowed down after the detection of the passage from the penultimate mark forming a mark, so as to stop the latter mark exactly at the predetermined location. 4. Method according to claims 1 and 3 characterized in that the end of the initial strip is gripped by hooking means which have, relative to the servo speed, a slight advance so that the strip is pulled with a slight tension. 5. Method according to claim 4, characterized in that the hooking means hold the end of the strip with a sliding to prevent tearing of the strip. 6. Method according to claim 1, characterized in that the winding of the wide web obtained after gluing the width sections is controlled by a cylinder and pressers pressed with equal force against said cylinder. 7. Method according to claims 1 and 6, characterized in that the winding of the wide web is controlled by signals emitted by the sensors which detect the geometry of the design of the initial web and / or of corresponding marks. 8. Device for positioning, cutting and distributing initial strips, with a view to forming wide strips, for placing implementing the method according to claims 1 to 7 characterized in that in the extension of a feed table 5 is provided a fixed positioning table 1, which is itself equipped with means (19, 20, 29) for pull an initial strip from the feed table and immobilize it on itself, and in that devices (9 or 12) for locating and positioning the strip are provided at least at the entrance and at the exit from the positioning table. 9. Positioning device according to claim 1, characterized in that the unwinding of the initial strip coming from the feed table 5 undergoes a lateral movement controlled by a photoelectric cell 39 which positions the original strip. 10. Positioning device according to claim 8, characterized in that the means for pulling an initial strip coming from the feed table 5 consist of endless belts 19 forming part of the positioning table 1 and each equipped with a attachment clip 20, the opening of which is ensured by a corresponding jack 29, said jacks being mounted directly above each belt, on a displaceable spacer 11 extending transversely above the positioning table, as well as on a fixed transverse beam 31. 11. Positioning device according to claim 10, characterized in that the endless belts 19 move in longitudinal notches 18 of the positioning table 1 by being flush with the level of said table or by disappearing below against in the notches . 12. Positioning device according to claims 8 and 10, characterized in that the gripping clamp 20 consists of a base 21 fixed to the endless belt 19 and a central rocker 23 articulated on said base, which ends with a pinch plate 25 held in abutment on the belt by a spring 27. 13. Positioning device according to claims 10 and 12, characterized in that the rod 28 of a jack 29 is applied to the central zone 30 of the rocker 23 of the attachment clip 20. 14. Positioning device according to claims 8 and 10 characterized in that the device for advancing the printed web is controlled by a first photoelectric cell 9 disposed at the output of the feed table 5 and a second photoelectric cell 12 located at level of the movable spacer 11. 15. Positioning device according to claims 8 and 14 characterized in that the first cell 9 activates the second cell 12 when the strip arrives near the spacer 11, and puts the unwinder 2 of the feed table 5 at idle . 16. Positioning device according to claims 8 and 14 characterized in that the first cell 9, after counting the marks, slows down the unwinder and detects the final position of the mark. 17. Positioning device according to claim 8, characterized in that one has plumb with a bank 10 of the positioning table 1 of a horizontal gluing bar 14 capable of being applied to the table under actuating cylinders 15. 18. Positioning device according to claim 8, characterized in that the winding of the new wide web is ensured by a cylinder 35 associated with pressers 36 pressed with equal force by jacks on said cylinder, a carrier cylinder disposed laterally at the table collecting the rolled up tape. 19. A positioning device according to claims 8 and 18, characterized in that a vertically movable table 38 is arranged along the positioning table to raise the free part of the wide web. 20. A positioning device according to claims 8 and 18 characterized in that the carrying cylinders 37 of the output winder have a slight advance in circumferential speed towards that of the cylinder 35 to ensure the regular winding of the strip.

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