PRESSING PAD FOR GLUING OR SMOOTHING DEVICES

Abstract

The present invention relates to a pressure pad of the type intended for applying a sheet product (1) to a support (3), comprising an outer wall (18) and an inner wall (20) between which is arranged a deformable and elastic assembly, wherein: the outer wall (18), the inner wall (20), and the deformable assembly (22, 24) form a single piece; the deformable assembly (22, 24) comprises a series of partitions (22) which connect the outer wall (18) and the inner wall (20) either to each other or to at least one intermediate wall (24). Figure for the abstract: Fig. 6

Description

Title of the invention: PRESSURE PAD FOR GLUING OR SMOOTHING DEVICES

[0001] The present invention relates to a pressure pad of the type intended for gluing or smoothing a sheet product such as a label on an article such as in particular a bottle, a flask, etc. It also relates to a method of manufacturing such a pressure pad.

[0002] It is known that the automated gluing and smoothing of labels on receiving supports, such as bottles in particular, uses foams which are pressed onto the label so as to apply it to the support in the precise position desired and without air bubbles forming.

[0003] Such an operation, in particular when the receiving supports are made up of bottles, which implies a curved receiving surface which is not of absolute regularity, requires the use of sizing or smoothing foams of sufficient flexibility so that they can absorb the surface irregularities of the bottle and nevertheless be sufficiently rigid to ensure effective application.

[0004] The foams used have the disadvantage of having a surface porosity which, during the gluing operation, generates a migration of the glue inside their cells which causes them to lose their elasticity during use and consequently disrupts the gluing process.

[0005] In order to overcome such a disadvantage, it is necessary to carry out cleaning frequently and periodically, which most of the time proves to be particularly difficult, so much so that they are generally forced to be replaced.

[0006] In order to avoid this drawback, it has also been proposed to apply a coating of liquid silicone to the contact surfaces of the foams in order to seal the pores. However, such a technique is expensive since it has to be carried out by hand and this does not make cleaning the foams any easier.

[0007] It has also been proposed to apply a polytetrafluoroethylene adhesive film (also known under the brand name "Teflon") to the surface of the sizing and smoothing foams, which also improves the homogeneity of the layer in contact with the bottles.

[0008] The adhesive foams also have the disadvantage of wearing out quickly, which means they need to be replaced frequently.

[0009] It has also been found that these foams, due to the irregularity of their surface, tend to generate the appearance of bubbles under the labels when they are applied to the latter.

[0010] Finally, since foams have a mainly isotropic texture, it is not possible to ensure that the foam has a given elasticity in its label application zone and a different elasticity in the zone where it is held on its support.

[0011] The aim of the present invention, in order to avoid the aforementioned drawbacks, is to propose a pressure pad intended to replace systems using gluing or smoothing foams which is easy to clean, easy to manufacture, virtually wear-free and whose elasticity can be adjusted in its application zone and in its holding zone.

[0012] The present invention thus relates to a pressure pad of the type intended to apply a sheet product to a support, comprising an external wall intended for the application of said sheet product to the support and an internal wall intended for its maintenance, between which is arranged a deformable and elastic assembly, characterized in that: - the external wall, the internal wall and the deformable assembly form a single piece, - the deformable assembly comprises a series of partitions which connect the external wall (18) and the internal wall either to each other or to at least one intermediate wall.

[0013] According to the invention, the deformable assembly may comprise, between its external wall and its internal wall, at least one intermediate wall, forming at least two inter-wall spaces, namely an external inter-wall space adjacent to the external wall and an internal inter-wall space adjacent to the internal wall, the latter, the external wall and the at least one intermediate wall being substantially parallel.

[0014] In the areas where they are connected to the external wall, the intermediate wall or the internal wall, the partitions may be substantially perpendicular or normal to the latter.

[0015] Furthermore, at least one inter-wall space may comprise partitions with a rectilinear cross section, and / or partitions with a C-shaped cross section and / or partitions with a JL-shaped cross section.

[0016] In embodiments of the invention, the outer wall and the inner wall may be in the form of concentric circular arcs. In addition, the outer wall, the inner wall and the at least one intermediate wall may be in the form of a circle.

[0017] The pressure pad may comprise at least two intermediate walls, the spacing of two adjacent partitions belonging to the external inter-wall space being able to be less than the spacing of two adjacent partitions belonging to the internal inter-wall space.

[0018] Finally, the pressure pad may be made of a material suitable for use in im- 3D type pressure as a manufacturing material.

[0019] The present invention also relates to a method of manufacturing a pressure pad as described above which will be formed by 3D printing.

[0020] Embodiments of the present invention will be described below, by way of non-limiting example, with reference to the appended drawing in which:

[0021] [Fig-1] is a schematic view of a gluing device according to the prior state of the technique which uses a pressure pad according to the invention to apply a glued label to a bottle,

[0022] [Fig.2] is a top view of a pressure pad according to the previous state of the technical,

[0023] [Fig.3] is a top view of a first example of a following pressure pad the invention wherein the partitions are substantially perpendicular to the outer wall and to the inner wall,

[0024] [Fig.4] is a top view of a second example of a following pressure pad the invention in which the partitions are C-shaped,

[0025] [Fig.5] is a top view of a third example of a following pressure pad the invention in which the partitions are S-shaped,

[0026] [Fig.6] is a top view of a fourth example of a following pressure pad the invention comprising several levels of partitions,

[0027] [Fig.7] is a schematic view of a smoothing device according to the prior art which uses a pressure pad according to the invention to apply a self-adhesive label to a bottle,

[0028] [Fig.8] is a top view of a pressure pad according to the invention of shape circular usable in a device such as that described with regard to the previous figure,

[0029] [Fig.9] is a schematic view of another smoothing device according to the state prior art which uses a pressure pad according to the invention to apply a self-adhesive label to a bottle,

[0030] [Fig. 10] is a top view of a pressure pad according to the invention of elongated shape usable in a device such as that described with reference to the preceding figure,

[0031] [Fig.l] shows a device according to the prior art which is intended to carry out the bonding of labels 1 on bottles 3.

[0032] The latter are distributed by a star wheel 5 between the branches 5a of which they are positioned, and which presents them in turn in front of a gluing assembly 8. The labels 1 are stacked and are driven one by one by a coating roller 7 which covers them with glue and transfers them against the bottle 3 which it is desired to garnish facing the gluing assembly 8.

[0033] The latter comprises gluing pressure pads 9 which are mounted on a rotating drum 11 and which, during the rotation of the latter, “unroll” the label 1 and apply it to the bottle 3.

[0034] In the prior art and as previously specified, such a pressure pad 9', as shown in [Fig. 2], consists of a receiving plate 12 on which is fixed an elastic foam 14 which is itself covered with a film of liquid silicone. This silicone film has the function of sealing the pores of the external surface of the foam 14 in order to prevent the absorption of the glue which will be deposited thereon by the glue roller 7.

[0035] According to the prior art, when the pressure pad is used as a smoothing pad, its external surface is coated with a film of "Teflon" 16 (polytetrafluoroethylene) which has the advantage of, on the one hand, closing the pores of the foam and, on the other hand, of being extremely smooth, a quality necessary to avoid the formation of air bubbles during smoothing.

[0036] [Fig. 3] shows an example of a pressure pad 9 according to the invention.

[0037] This has the same external geometry as the pressure pads of the prior art, which allows the user to replace them on the gluing assemblies without having to make modifications to the latter.

[0038] It will first be noted that the pressure pad 9 according to the invention is made in a single piece, namely in a material preferably usable in the field of so-called 3D printing, namely in particular thermoplastic tetrapolyurethane or “TPU” or in any other material usable in the field of 3D printing, insofar as a preferred method of manufacturing the pressure pad according to the invention is 3D printing, as explained later.

[0039] In the present embodiment, the pressure pad 9 which has the overall shape of a portion of a cylinder comprises an external wall 18, and an internal wall 20, which are in the shape of portions of concentric circles, these two walls being connected to each other by partitions 22. It is understood that these partitions 22 give the pressure pad 9 a rigidity which depends on the one hand on the nature of the material used to manufacture it and on the other hand on the thickness e of these partitions, as well as also on their number. The internal wall 20 is fixed, in particular by gluing means or mechanical holding means, on the receiving plate 12 which is integral with the drum 11.

[0040] It is known that a first condition for the proper functioning of the pressure pad 9 according to the invention is that it must be sufficiently flexible and elastic so that its external wall 18 deforms sufficiently so that it can adapt to the irregularities surface of the external wall of the bottle 3 on which it presses the label 1 to be stuck.

[0041] It is also known that a second condition for proper operation is that the deformation of this external wall 18 occurs regularly during its relative displacement movement relative to the bottle 3. To fulfill this second condition, the invention gives those skilled in the art the possibility of controlling the rigidity of this external wall 18 by producing a sufficient number of partitions 22 to avoid such excessive deformation.

[0042] It is understood, however, that by producing the number of partitions 22 necessary to achieve the second condition, the person skilled in the art thus increases the stiffness of the external wall 18 and that, consequently, the pressure pad 9 risks no longer fulfilling the first condition, namely a deformability of said external wall 18 which is sufficient to ensure correct application of the label 1 on the bottle 3 despite the surface irregularities thereof.

[0043] The present invention is particularly interesting in that it allows a person skilled in the art to avoid such a situation by giving him the possibility of controlling the flexibility of the external wall 18 by then playing on other parameters and firstly on the thickness e of the partitions.

[0044] The present invention offers the person skilled in the art another parameter enabling him to reduce in a controlled manner the flexibility of the external wall 18, namely the shape of the partitions 22.

[0045] Indeed, as shown in [Fig.4], these partitions 22 may have a curved shape, in particular in the shape of a Ç, the concavities of the latter being able to be symmetrical with respect to the axis of symmetry yy' of the pressure pad.

[0046] The partitions 22 can also be given an S-shaped profile, as shown in [Fig. 5], experience showing that, for equal partition thickness e, the flexibility conferred on the wall 18 is greater than that of the C-shaped configuration.

[0047] According to the invention, the partitions can be produced by forming them on several “stages” and in particular on three stages as shown in [Fig. 6]. In the present application, the spaces (X, Y, Z) existing between intermediate walls 24 arranged between the external wall 18 and the internal wall 20 of the pressure pad and which are in particular parallel to the latter will be called stages.

[0048] It is understood that such a “tiered” arrangement is particularly interesting in that it makes it possible to control the flexibility at several levels of the pressure pad.

[0049] Indeed, and as explained previously, it must be sufficiently flexible so that its external wall 18 can deform sufficiently so that it can adapt to the surface irregularities of the external wall of the bottle. Furthermore, to the extent that the bottles, due to their method of manufacture, may have differences in important structure, particularly in terms of their dimensions and their curvature, the pressure pad as a whole must be able to deform sufficiently to adapt to these deformations of the bottles.

[0050] The stepped distribution of the present embodiment makes it possible to give the base of the pressure pad greater flexibility, in order to allow it better positioning relative to the bottle, while giving its external wall greater rigidity necessary for the effective application of the label to the wall of the bottle.

[0051] This difference in rigidity is obtained by varying the shape and number of partitions per stage. Thus, in the example illustrated in [Fig.6] where it is desired to have a greater rigidity of the external wall 18 than that of the base of the pressure pad, more C-shaped partitions 22 are produced on the external stage X than on the intermediate stage Y and the internal stage Z.

[0052] It would also be possible to use partitions of different shapes in some of the floors depending on the specific rigidity that one wishes to give to these different floors.

[0053] It would also be possible, depending on the requirements imposed by certain specific designs, to ensure that the external stage X is more flexible than the intermediate stage Y and the internal stage Z.

[0054] The present invention is also applicable to pressure pads which are used in devices using generally different shapes and in particular to devices carrying out smoothing of labels on receiving elements.

[0055] [Fig. 7] shows such a smoothing device in which the labels 1 used are held on a support strip 26 which is wound onto a distributor roller 28 and which moves to be wound onto a receiving roller 30 following a path which brings each label 1 into contact with the bottle 3 to be covered.

[0056] The bottles 3 are moved in the direction of the arrow F so that they each present themselves in turn facing two drive rollers 32 rotating in opposite directions and which are applied to them by pressure means 33 so as to drive this bottle 3 in rotation.

[0057] In this embodiment of the invention, the pressure pad 9 according to the invention is in the form of a cylinder whose walls come into contact with the label 1 engaged on the bottle 3 and which, during the rotation of the latter, applies it against this bottle.

[0058] [Fig. 8] shows such a two-stage type pressure pad, namely an external stage X adjacent to the external wall 18, an internal stage Z adjacent to the internal wall 20 which are separated by an intermediate wall 24 which is arranged at an equal distance from the external and internal walls.

[0059] In this example of implementation of the invention, use has been made of partitions 22 in the shape of a C, the number of which is greater in the external stage X than in the internal stage Z so that the rigidity of the external stage is greater than that of the internal stage.

[0060] It would of course be possible, while remaining within the scope of the present invention and depending on specific applications, to proceed in reverse and create pressure pads in which the external stage would be of lower rigidity than the internal stage.

[0061] According to the invention, it would also be possible to produce pressure pads having any number of stages depending on the specific applications.

[0062] It will be noted that certain smoothing devices according to the prior art are of the type shown in [Fig.9].

[0063] In this smoothing device the labels 1 used are held as previously on a support strip 26 which is wound onto a distributor roller 28 and which moves to be wound onto a receiving roller 30 following a path which brings each label 1 into contact with the bottle 3 to be covered.

[0064] The bottles are moved in the direction of the arrow F so that they are each presented in turn between the pressure pad 9 and a conveyor belt 35 driven in rotation by two rotating drums 37. The conveyor belt 35 imparts a rotational movement to the bottle and applies it against the pressure pad 9 with the interposition of the label 1.

[0065] In this embodiment of the invention, the pressure pad 9 according to the invention is in an elongated form so that when the bottle rolls against it, this movement applies the label against the bottle, which ensures its smoothing. The external wall 18 of the pressure pad 9 has, in this configuration, a straight shape with a slight curve in its middle and its internal wall 20 is substantially parallel to it.

[0066] Furthermore, it is of the three-stage type, the external stage X being less wide than the intermediate stage Y and the internal stage Z, the partitions 22 of the external stage X will be shorter than the partitions allocated to the other stages. In addition, the external stage X has more partitions 22 than the other two stages. It is understood under these conditions that the external stage X will be of greater rigidity than the other two stages.

[0067] The present invention is particularly interesting in that, on the one hand, it allows the pressure pad to be manufactured particularly easily by 3D printing, the surface quality of its external wall making it possible to do without both the silicone film (gluing pad) and the Teflon film (smoothing pad) and, on the other hand, insofar as it allows the person skilled in the art to produce pads pressers whose stiffness he perfectly controls, he is able, depending on specific needs, to assign a different and controlled stiffness to the different X, Y, Z zones.

Claims

Claims

1. Pressure pad of the type intended to be mounted on a rotating drum which, during its rotation, applies a sheet product (1) onto a support (3), this pressure pad comprising an external wall (18) intended for the application of said sheet product onto the support and an internal wall (20) intended for its retention between which is arranged a deformable and elastic assembly, - the external wall (18), the internal wall (20) and the deformable assembly (22, 24) forming a single piece, - the deformable assembly (22, 24) comprising a series of partitions (22) which connect the external wall (18) and the internal wall (20) either to each other or to at least one intermediate wall (24), characterized in that the deformable assembly comprises, between its external wall (18) and its internal wall (20), at least one intermediate wall (24), forming at least two inter-wall spaces,namely an external inter-wall space (X) adjacent to the external wall (18) and an internal inter-wall space (Z) adjacent to the internal wall (20), the latter, the external wall (18) and the at least one intermediate wall (24) being substantially parallel.,

2. Pressure pad according to claim 1 characterized in that the partitions (22), in the zones where they are connected to the external wall (18), to the intermediate wall (24) or to the internal wall (20) are substantially perpendicular to the latter.

3. - Pressure pad according to one of claims 1 or 2 characterized in that at least one inter-wall space (X, Y, Z) comprises partitions (22) with a rectilinear cross section.

4. Pressure pad according to one of claims 1 or 2 characterized in that at least one inter-wall space (X, Y, Z) comprises partitions (22) with a cross section in the shape of a C.

5. - Pressure pad according to one of claims 1 or 2 characterized in that at least one inter-wall space (X, Y, Z) comprises partitions (22) with an S-shaped cross section.

6. - Pressure pad according to any one of the preceding claims, characterized in that the external wall (18) and the internal wall

7.

8.

9. (20) are in the form of concentric circular arcs. Pressure pad according to any one of the preceding claims, characterized in that the external wall (18), the internal wall (20) and the at least one intermediate wall (24) are in the shape of a circle. - Pressure pad according to any one of the preceding claims, characterized in that it comprises at least two intermediate walls (24), the spacing of two adjacent partitions belonging to the inter-wall space (X) being less than the spacing of two adjacent partitions belonging to the internal inter-wall space (Z). - Pressure pad according to any one of the preceding claims, characterized in that it is made of a material suitable for use as a manufacturing material in 3D printing.

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