FR3132508A1 - PRESSING PAD FOR GLUING OR SMOOTHING DEVICES - Google Patents

Abstract

The present invention relates to a pressing pad of the type intended to apply a product in sheet form (1) to a support (3), comprising an outer wall (18) and an inner wall (20) between which is arranged a deformable and elastic assembly, characterized in that: 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 abstract: Fig.6

Description

PRESSURE PAD FOR GLUING OR SMOOTHING DEVICES

The present invention relates to a pressure pad of the type intended to carry out the gluing or smoothing of a sheet product such as a label on an article such as in particular a bottle, a vial etc. It also relates to a method of manufacturing 'such a pressure pad.

We know 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 desired precise position and without air bubbles forming.

Such an operation, particularly when the receiving supports are made of bottles, which implies a curved receiving surface and which is not absolutely regular, requires the use of flexible gluing or smoothing foams. sufficient so that they can absorb the surface irregularities of the bottle and yet be sufficiently rigid to ensure effective application.

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

In order to overcome such a disadvantage, we are forced to carry out cleaning often and periodically, which most of the time proves particularly difficult, so much so that we are generally forced to replace them.

In order to avoid this drawback, it has also been proposed to coat the contact surfaces of the foams with liquid silicone so as to close the pores. However, such a technique turns out to be expensive since it must be carried out by hand and this without necessarily making cleaning the foams much easier.

It has also been proposed to affix to the surface of the gluing and smoothing foams an adhesive film of polytetrafluoroethylene (also known under the brand "Teflon") which also makes it possible to improve the homogeneity of the layer in contact with the bottles.

Gluing foams also have the disadvantage of wearing out quickly, requiring frequent replacement.

It has also been observed 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 them.

Finally, since the foams have a mainly isotropic texture, we cannot ensure that the foam has a given elasticity in its area of application of the label and a different elasticity in the area where it is held on its support.

The present invention aims, in order to avoid the aforementioned drawbacks, to propose a pressing pad intended to replace systems using gluing or smoothing foams which is easily cleanable, easy to manufacture, almost indestructible and which can be can adjust the elasticity in its application area and in its holding area.

The subject of the present invention is thus a pressing pad of the type intended to apply a sheet product on a support, comprising an external wall intended for the application of said sheet product on the support and an internal wall intended for maintaining it, between which a deformable and elastic assembly is arranged, characterized in that:

• the external wall, the internal wall and the deformable assembly form a single part,
• 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.

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

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.

Furthermore, at least one inter-wall space may include partitions with a rectilinear cross section, and/or partitions with a C- shaped cross section and/or partitions with an S -shaped cross section.

In embodiments of the invention, the outer wall and the inner wall may be in the shape of concentric arcs of a circle. In addition, the external wall, the internal wall and at least one intermediate wall may be in the shape of a circle.

The pressure pad may include 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.

Finally, the pressure pad may be made of a material suitable for use in 3D printing as a manufacturing material.

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

We will describe below, by way of non-limiting example, embodiments of the present invention, with reference to the appended drawing in which:

is a schematic view of a gluing device according to the prior state of the technique which uses a pressing pad according to the invention to apply a glued label to a bottle,

is a top view of a pressure pad according to the prior state of the art,

is a top view of a first example of a pressure pad according to the invention in which the partitions are substantially perpendicular to the external wall and the internal wall,

is a top view of a second example of a pressure pad according to the invention in which the partitions are C-shaped,

is a top view of a third example of a pressure pad according to the invention in which the partitions are S-shaped,

is a top view of a fourth example of a pressure pad according to the invention comprising several stages of partitions,

is a schematic view of a smoothing device according to the prior state of the technique which uses a pressing pad according to the invention to apply a self-adhesive label to a bottle,

is a top view of a pressing pad according to the invention of circular shape usable in a device such as that described with reference to the previous figure,

is a schematic view of another smoothing device according to the prior state of the technique which uses a pressing pad according to the invention to apply a self-adhesive label to a bottle,

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,

We represented on the a device according to the prior state of the technique which is intended to carry out the sticking of labels 1 on bottles 3.

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 for their part are stacked and are driven one by one by a coating roller 7 which coats them with glue and transfers them against the bottle 3 which we wish to fill facing the gluing assembly 8.

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

In the prior state of the technique and as previously specified, such a pressure pad 9', as shown in the , consists of a receiving plate 12 on which is fixed an elastic foam 14 which is itself covered with a film of liquid silicone. The function of this silicone film is to block 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 gluing roller 7.

According to the prior state of the art, when the pressing 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 close the pores of the foam and on the other hand to be extremely smooth, a quality necessary to avoid the formation of air bubbles during smoothing.

We represented on the an example of a pressure pad 9 according to the invention.

This has the same external geometry as the pressure pads of the prior state of the art, which allows the user to replace them on the gluing assemblies without being forced to make modifications to the latter.

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

In the present mode of implementation, the pressing pad 9 which generally has the 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 together 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 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.

We know that a first condition for good operation 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 match the surface irregularities of the wall. external of the bottle 3 on which it presses the label 1 to stick.

We also know that a second condition for good operation is that the deformation of this external wall 18 takes place regularly during its relative displacement movement relative to the bottle 3. To fulfill this second condition the invention gives the Those skilled in the art have the possibility of controlling the rigidity of this external wall 18 by producing a sufficient number of partitions 22 to avoid such excessive deformation.

We understand, however, that by producing the number of partitions 22 necessary to achieve the second condition, the skilled person thus increases the stiffness of the external wall 18 and that, therefore, the pressure pad 9 risks no longer filling 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.

The present invention is particularly interesting in that it allows those 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 adjusting other parameters and firstly on the thickness e of the partitions.

The present invention offers those skilled in the art another parameter enabling them to reduce the flexibility of the external wall 18 in a controlled manner, namely the shape of the partitions 22.

Indeed, as shown on the , these partitions 22 can have a curved shape, in particular C -shaped, the concavities of the latter can be symmetrical with respect to the axis of symmetry yy' of the pressing pad.

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

According to the invention, the partitions can be produced by forming them on several “floors” and in particular on three floors as shown in the . We will call stages 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.

We understand 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.

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

The tiered distribution of this method of implementation makes it possible to give the base of the pressing pad greater flexibility, in order to allow it better positioning in relation to the bottle, while giving its external wall greater rigidity as required. to the effective application of the label on the wall of the bottle.

This difference in rigidity is obtained by varying the shape and number of partitions per floor. So in the example illustrated on the where we wish to have a greater rigidity of the external wall 18 than that of the base of the pressure pad, more C partitions 22 are produced on the external stage X than on the intermediate stage Y and the stage internal Z.

We could also use partitions of different shapes on some of the floors depending on the specific rigidity that we wish to give to these different floors.

We could also, depending on the requirements imposed by certain specific implementations, ensure that the external stage X is more flexible than the intermediate stage Y and the internal stage Z.

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

We represented on the such a smoothing device in which the labels 1 used are held on a support strip 26 which is wound on a distributor roller 28 and which moves to wind on a receiving roller 30 following a path which brings each label 1 into contact with bottle 3 to cover.

The bottles 3 for their part are moved in the direction of the arrow F so that they each in turn face two drive rollers 32 rotating in opposite directions and which are applied to them by pressure means 33 so as to cause this bottle 3 to rotate.

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 comes during the rotation of this apply it against this bottle.

We represented on the such a two-stage type pressure pad, namely an external stage and internal.

In this example of implementation of the invention, C- shaped partitions 22 have been used, the number of which is greater in the external stage X than in the internal stage Z so that the rigidity of the stage external is greater than that of the internal stage.

We could of course, while remaining within the field of the present invention and depending on specific applications, proceed inversely and create pressure pads in which the external stage would be of lower rigidity than that of the internal stage.

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

It will be noted that certain smoothing devices according to the prior state of the technique are of the type shown on the .

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

The bottles for their part are moved in the direction of arrow F so that they are each in turn between the pressing pad 9 and a treadmill 35 driven in rotation by two rotating drums 37. The treadmill 35 prints a rotational movement to the bottle and applies it against the pressure pad 9 with the interposition of the label 1.

In this mode of implementation 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 curvature in its middle and its internal wall 20 is substantially parallel to it.

Furthermore it is of the three-stage type, the external stage X being narrower than the intermediate stage Y and the internal stage Z , the partitions 22 of the external stage floors. In addition, the external floor X has more partitions 22 than the other two floors. We understand under these conditions that the external stage X will be of greater rigidity than the other two stages.

The present invention is particularly interesting in that on the one hand it allows the manufacture of the pressure pad in a particularly easy manner in 3D printing, the surface quality of its external wall making it possible to do without the silicone film (pressure pad). gluing) than that of Teflon (smoothing pad) and on the other hand, to the extent that it allows those skilled in the art to produce pressing pads whose stiffness they perfectly control, the latter is able, in depending on specific needs, to assign a different and controlled stiffness to the different zones X, Y, Z.

Claims (11)

Press pad of the type intended to apply a sheet product (1) to a support (3), comprising an external wall (18) intended for the application of said sheet product on the support and an internal wall (20) intended for its support between which is arranged a deformable and elastic assembly, characterized in that:

• the external wall (18), the internal wall (20) and the deformable assembly (22, 24) form a single part,
• the deformable assembly (22, 24) comprises 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).

Press pad according to claim 1 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 an intermediate wall (24) being substantially parallel. Pressing pad according to one of claims 1 or 2 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. - Press pad according to one of claims 2 or 3 characterized in that at least one inter-wall space (X, Y, Z) comprises partitions (22) of rectilinear cross section. Press pad according to one of claims 2 or 3 characterized in that at least one inter-wall space (X, Y, Z) comprises partitions (22) with a C -shaped cross section. - Press pad according to one of claims 2 or 3 characterized in that at least one inter-wall space (X, Y, Z) comprises partitions (22) with a cross section in the shape of an S. - Press pad according to any one of the preceding claims characterized in that the external wall (18) and the internal wall (20) are in the shape of concentric arcs of a circle. Press pad according to one of claims 2 to 7 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. - Press pad according to one of claims 2 to 8 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 l spacing of two adjacent partitions belonging to the internal inter-wall space (Z). - Press 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 type printing. - Method for manufacturing a pressure pad according to any one of the preceding claims, characterized in that said pressure pad is formed by 3D type printing.