EP0773900B1 - Separator, in particular for paper or cardboard webs - Google Patents

Description

The present invention relates to a device separator intended to ensure rigorous identification, in the longitudinal direction, bands resulting from the slitting a web in web presses transformation of paper, film, or fabric, into shaping machines especially intended for manufacture of labels.

We know that after the slitting operation intended for create adjoining strips in a sheet of paper there is often necessary to positively position the different bands between separating cheeks provided on a return cylinder. The implementation of such retractors implies that one intervenes on the adjustment of these whenever you want to change either the number or the width tapes. We also know that such an implementation work is limited by the tension of the tablecloth and / or by the length of the input and output strands when one wishes not to damage the support.

We know in particular by GB-A-2,144,106 tape spacers which are made up of a series of small cylindrical rollers which are arranged next to each other on a support which is curved. Such devices have the disadvantage of making a variation in curvature which is applied in successive steps corresponding to the length of each of the rollers. In such devices so there is no gradual variation curvature, so much so artwork can only be used in devices that do not require high precision.

It has also been proposed, in the prior state of the technique, and in particular in an article entitled "Separating slit strip and foil" from a magazine "Engineering March 1973" to realize the spacing of bands by means of spacer cylinders or "cylinders bananas ". These cylinders consist of an axis curved metal, whose curvature is sometimes adjustable in amplitude and orientation, on which are mounted, in free rotation, next to the others, metal rings. Rings are sometimes coated with an elastic elastomer sleeve, which makes it possible in particular to smooth the curvature of the outer surface of these cylinders.

Spacer cylinders of this type have the disadvantage of not forming a regular curve since, by construction, they are made up of a series of adjacent rectilinear elements thus forming a broken line. If the curvature of such cylinders is regular enough to provide lateral separation of the paper strips it does not allow, on the other hand, because of this lack of regularity of their curvature, to provide a location different bands with respect to each other which is perfect in the longitudinal direction. Indeed the width of the strips obtained by the slitting is not, at least most of the time, equal to the width different rectilinear elements, so that a band can come to bear on several elements which destroys its rigorous tracking in the sense longitudinal. However, such machines must ensure perfect alignment in the longitudinal direction for strips of any width without any readjustment mechanical.

It has also been proposed, in patent US-A-4,566,154, and for modes of implementation individuals, to use roller sets spaced from each other, consisting of a first series of curved upstream rollers and a second series of downstream rollers each having their part central a different curvature of the curvatures of their extremities.

Finally, we know from US-A-4,146,947 patent separator rollers consisting of a central axis on which are arranged with multiple adjacent rollers, the assembly being covered with an elastic sleeve deformable, and the central axis can be subjected to torsional stresses.

For the reasons mentioned above, especially due to the fact that these rollers do not do not have a strictly regular curvature, they can only be used in areas where extreme precision is not required.

Relative identification of the bands relative to each other to others in the longitudinal direction is important when you want to cut these strips so that constitute elements of small dimensions, such as for example labels. To ensure such cutting, we know that we have to cut in the direction transverse the previously spaced bands. This cutting is carried out most of the time by a one and the same cross chisel which cuts both the labels of the different bands all over the width of the tablecloth. We understand under these conditions, that the slightest offset in the longitudinal direction of a band relative to each other would have the effect of translate at the cutting level by an error, either more or less than the nominal dimension of each of the cut labels. That is why in the prior art, this cut transverse is usually performed on bands which have not been separated from each other.

The object of the present invention is to provide a separating device making it possible to obtain, after the slitting of a sheet and the spacing of the bands formed, a rigorous longitudinal positioning of these relative to each other, allowing their precise transverse cutting with a transverse scissor unique.

The subject of the present invention is therefore a tape separation device, especially for tape separation of paper or cardboard, obtained after the slitting of a tablecloth, of the type comprising two separating cylinders curves, or "banana cylinders", namely a cylinder upper upstream and a lower downstream cylinder, the water table bearing on the upper part of the cylinder upstream and on the lower part of the downstream cylinder, in which the two separator cylinders upstream and downstream are of the same diameter and their axes longitudinal are contained in parallel planes substantially vertical perpendicular to surfaces respective of the water table at the input and output of the two separator cylinders, the concavity of each of these being oriented upwards, the curvature of each said cylinders being such that any perpendicular lowered from any point on the longitudinal axis of each of the cylinders, on the longitudinal axis of the other cylinder, is of the same length, characterized in that the separating cylinders consist of rectilinear and monoblock elements at the ends of which is applied a bending moment so as to give them a regular curvature.

In one embodiment of the invention, the elements of the input and output tablecloth are in respective support on straight cylinders, respectively arranged upstream and downstream of separating cylinders upstream and downstream, the distances respective of these cylinders straight to said cylinders upstream and downstream separators being important in comparison of the deflection of each separating cylinder.

In another embodiment of the invention, the curvatures of each of the two cylinders upstream and downstream separators are arcs of a circle. These interestingly, arcs of a circle can be perfectly concentric with a fictitious axis located at the intersection of the plane of symmetry of the upstream parts and downstream of the tablecloth that enters and leaves the device, with a plane parallel to these said parts.

We will describe below, by way of example not limiting, an embodiment of this invention, with reference to the attached drawing in which:

Figure 1 is a perspective view of a device according to the present invention.

Figure 2 is a schematic view, in section vertical along the longitudinal plane of symmetry of the sheet, of the device shown in FIG. 1.

Figure 3 is a schematic sectional view along line III-III of Figure 2 of a mode of implementation of the invention, the web not being in square.

Figure 4 is a cross-sectional view to larger scale of an implementation mode of a separator cylinder according to the invention.

Figures 4a and 4b are schematic views of two stages of implementation of the variant shown in Figure 4.

Figure 5 is a schematic cross-sectional view of an embodiment of the variant shown in figure 4.

Figure 6 is a cross-sectional view illustrating a method of manufacturing a cylinder separator used according to the invention.

There is shown in Figures 1 and 2 a sheet in paper 1 which is received on a first right cylinder 3 which ensures its maintenance so that means of cutting 5 can split the sheet 1 in order to make up seven parallel strips of paper and adjacent 7. The strips 7, once cut, are supported on the upper face of a cylinder upstream separator 9. The upstream separator cylinder 9, which is shown in detail in Figure 4, consists of a tubular element which is curved in the shape of an arc of circle of radius r, the concavity of this cylinder being facing upwards and being contained in a plane P vertical, preferably perpendicular to the plane of the tablecloth 1. The passage of parallel and adjacent strips 7 on the banana cylinder 9 ensures, in a setting mode in work, the rotational drive thereof and, in known manner, the separation and spacing of bands 7 so that at the outlet of the separating cylinder upstream 9 the paper strips 7 are no longer parallel but are angularly separated from each other at a given angle as a function of the curvature of the separator cylinder 9. Most of the time separator cylinders will be animated by a movement of rotation under the action of drive means, well that in certain modes of implementation training is achieved by moving the bands themselves. Tapes 7 are then received on the underside of a second separator cylinder downstream 9 'on which they are supported. The cylinder downstream separator 9 'has the same diameter as the cylinder upstream separator 9 and is mechanically arranged from the same way as this one. This cylinder thus has a radius of curvature r ', its concavity being contained in a second plane P 'parallel to the plane P and being also directed upwards. The separator cylinder downstream 9 'is arranged at a level lower than that of upstream separator cylinder 9 and all perpendicular lowered by any point A1, A2, ... An of the axis longitudinal VV 'or WW' of each of the cylinders separators on the longitudinal axis of the other cylinder separator has the same length.

The strips 7 after passing over the downstream cylinder 9 ′ emerge from the latter parallel to one another and spaced from each other by a distance e . At the outlet of the downstream separating cylinder 9 ′, the bands 7 are supported on a second straight cylinder 11 which makes it possible to ensure their tension, and the downstream part 1 ′ of the sheet is parallel to its upstream part 1.

As shown in Figure 3, the cylinders upstream 9 and downstream 9 'separators have arrows respective f and f 'which are a function of the spacing e that we want to give to the bands 7.

According to the invention the length h ₁ , h ₂ , ... h _n of each perpendicular A ₁ B ₁ , A ₂ B ₂ , ... A _n B _n lowered from the longitudinal axis vv 'of the separating cylinder 9 on the longitudinal axis ww 'of the other separating cylinder 9' has a constant value. Preferably, the longitudinal distance a separating the first right cylinder 3, from the upstream separating cylinder 9 and the distance b separating the downstream separating cylinder 9 'from the second right cylinder 11, are large compared to the arrows f and f' of the separating cylinders 9 and 9 '. Of course one could also use cylinders 9 and 9 'whose length of each perpendicular lowered from the longitudinal axis ww' of the downstream separating cylinder 9 'on the longitudinal axis vv' of the upstream separating cylinder would be constant.

Particularly interesting, and like shown in Figure 3, the separator cylinders upstream 9 and downstream 9 'are in the form of arcs of circles of respective radii r and r '. These arcs are perfectly concentric with a fictitious longitudinal axis uu 'located at the intersection of the plane of symmetry Q of upstream 1 and downstream 1 ′ parts of the sheet which enter and coming out of the device, with an R plane perpendicular to the plane Q and parallel to these said parts.

The curvature of the separating cylinders 9, 9 'is obtained by deformation of straight cylinders monoblocks to which one applies, at their ends respective, a moment of bending.

FIG. 4 thus represents a mode of realization in which the curvature of each of the upstream and downstream cylinders is obtained by deformation of a straight cylinder element.

In Figure 4 a separator cylinder 9 is consisting of a metallic tubular element, the wall has a sufficient thickness of the order of 4 at 5 mm, avoiding any ovalization during work under the effect of the stressing forces on the sheet. Each end of the tubular element 9 is embedded in a sleeve 17 which is disposed at inside two bearings 19 themselves recessed in a support element 21. Originally, as shown in Figure 4a, the tubular member 9 is straight, and then apply as shown in schematic figure 4b, a moment of rotation M at each of the support elements 21, so as to give the tubular element 9 the appropriate curvature. The plaintiff has thus established that this mode of implementation work allowed to obtain, for each of the cylinders upstream 9 and downstream 9 'separators a curvature perfectly regular.

It was found that the regularity of this curvature was such that it produced a perfect alignment of the seven paper strips in the direction longitudinal. That is, as shown in the FIG. 1, if one carries out upstream of the upstream cylinder 9, a transverse marking forming on the bands adjacent 7 a series of aligned transverse segments along a straight line LL ', we find, downstream of downstream cylinder 9 ', and after transverse separation of bands 7, transverse segments on each of bands which are also aligned along a line right NN '.

The present invention thus makes it possible to carry out the cutting a set of strips beforehand pre-printed and spread apart with a knife single transverse.

As shown schematically in the figure 5 the bending moment M applied to each of the elements support 21 arranged at the ends of the cylinders separators 9 and 9 'can be obtained by performing on this element supports a chamfered surface 23 which is inclined by the angle α which we wish to rotate the support element 21 relative to the longitudinal axis vv 'of the separating cylinder. 25 tie rods allow to clamp the chamfered surface 23 by compared to a plan 27 provided for this purpose on the machine.

The separating cylinders of the following device the invention may consist of massive elements metallic or not. In particular, the metals known for good resistance to fatigue. We will therefore particularly remember steels able to withstand repetitive stresses such as than chromium or manganese steels. Most of the time, the separator cylinders will advantageously produced in tubular form.

Such separating cylinders can also be made from composite materials, i.e. of materials made of resin reinforced by fibers, especially glass, carbon or "Kevlar".

We illustrated in Figure 6 such a setting mode of the invention. We use a cylindrical mandrel 29 on which one comes to wind fibers consisting in particular of carbon, "Kevlar" or glass. The cohesion between these fibers is provided by a resin, in particular an epoxy resin. We may also use pre-coated fibers of a polymer, which, after passing through a nozzle heating, will regain their adhesive character, adhesive character which will ensure the bonding of the fibers between them. Preferably, the fibers will be wound on the mandrel 29 at an angle  relative to the longitudinal axis vv 'thereof. The inclination  of fibers relative to the axis of the mandrel 29 will allow control the direction of mechanical characteristics preferential of the sleeve thus formed. We will understand that fibers inclined on the axis longitudinal vv 'with a small angle  will give the sleeve preferably axial mechanical strength while fibers inclined at an angle  close to 90 ° will give the sleeve 29 thus formed a radial preferential resistance.

Once the winding is done we will remove the mandrel of the scabbard, this operation possibly being facilitated by the provision thereon of an element anti adhesive.

In order to improve the regularity of the surface external of such sleeves, we will eventually have on their periphery a varnish, and in particular a varnish epoxy, which will subsequently correct the external surface of the mandrel without carrying damage to the mechanical integrity of the fibers.

In the embodiment described above, separator cylinders are used of elements rotatably mounted about their axis longitudinal. In a following mode of implementation the invention it is also possible to use cylinders dividers that are attached at their ends, the moving the cut strips then by friction on the external surface of these. Such mode of implementation of the invention, allows, in some cases to simplify the mechanical constitution of the system used, to the detriment of course wear separator cylinders.

Claims (10)

1. Device for separating strips, particularly strips of paper or of cardboard, obtained after the slitting of a web (1), of the type comprising two curved separator rollers, or "banana rollers" (9, 9'), namely an upper upstream roller (9) and a lower downstream roller (9'), the web (1) abutting on the upper part of the upstream roller (9) and on the lower part of the downstream roller (9'), in which the two upstream (9) and downstream (9') separator rollers present the same diameter and their longitudinal axes (vv', ww') are contained in substantially vertical, parallel planes (P, P') perpendicular to the respective surfaces of the web at the entrance (1) and at the outlet (1') of the two separator rollers, the concavity of each of the latter being oriented upwardly, the curvature of each of said rollers being such that any perpendicular dropped from any point (A1, A2, ...Am) of the longitudinal axis (vv', ww') of each of the rollers, onto the longitudinal axis (ww', w') of the other roller, is of the same length, characterized in that the separator rollers (9, 9') are constituted by rectilinear one-piece elements, at the ends of which is applied a moment of flexion (M) so as to give them a regular curvature (2, 2').
2. Device according to Claim 1, characterized in that the separator rollers (9, 9') are constituted by tubular elements.
3. Device according to one of the preceding Claims, characterized in that the ends of the separator rollers (9, 9') are fitted in roller bearings (17, 19).
4. Device according to Claim 3, characterized in that the roller bearings (17, 19) are connected to rigid blocks (21) comprising a face (23) inclined with respect to the axis (vv', ww') of the separator roller, by an angle (α) by which it is desired to rotate each of the blocks (21) in order to curve the separator roller, and clamping means (25) adapted to apply this inclined surface (23) against a surface (27) of the machine.
5. Device according to one of the preceding Claims, characterized in that the elements of the web at the inlet (1) and at the outlet (1') are in respective abutment on straight rollers (3, 3'), respectively disposed upstream and downstream of the separator rollers (9, 9'), the respective distances from these straight rollers (3, 3') to said upstream (9) and downstream (9') separator rollers being large in comparison to the camber (f, f') of each separator roller (9, 9').
6. Device according to one of the preceding Claims, characterized in that the curvatures of each of the two upstream (9) and downstream (9') separator rollers are constituted by arcs of circle.
7. Device according to Claim 6, characterized in that said arcs of circle are perfectly concentric to an imaginary axis (uu') located at the intersection of the plane of symmetry (Q) of the upstream (1) and downstream (1') parts of the web which enter and leave the device, with a plane (R) parallel to these said parts (1, 1).
8. Device according to one of the preceding Claims, characterized in that the separator rollers (9, 9') are constituted, at least on the periphery, by windings of fibers bound together by means of a hardenable binding agent.
9. Device according to Claim 8, characterized in that the windings are inclined with respect to the longitudinal axis (vv', ww') of the separator rollers.
10. Device according to one of Claims 8 or 9, characterized in that each separator cylinder (9, 9') is coated, on its periphery, with a hardenable resin adapted to undergo a grinding without being detrimental to the mechanical integrity of the windings.

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