|
(11) | EP 1 447 190 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||||||
| (54) | Method for making tiles |
| (57) A method for transferring granular material (3, 16, 17, 18), comprises preparing
on a surface (1) layer means (3) of said granular material (3, 16, 17, 18) arranged
for constituting at least a main part of the thickness (S) of a tile (4), compacting
said layer means (3) on said surface (1), transferring said layer means (3) by vacuum
means (8), said preparing comprising preparing layer means (3) with dimensions exceeding
the perimeter of said tile (4); an apparatus for transferring granular material (3,
16, 17, 18), comprises distributing means suitable for preparing on a surface (1)
layer means (3) of said granular material (3, 16, 17, 18) arranged for constituting
at least a main part (S) of a tile (4), compacting means (5, 6, 10, 23) suitable for
compacting said layer means (3) on said surface (1), transferring means (7, 8, 9,
10, 11) suitable for transferring said layer means (3) by vacuum means (8), said distributing
means being suitable for preparing in said surface (1) said layer means (3) having
dimensions exceeding the perimeter of said tile (4). |
[0001] The invention concerns a method for preparing and transferring granular material, in particular for feeding pressing moulds in the process for producing ceramic tiles.
[0002] A known method for feeding a cavity of a mould, described for example in US 4306595 and in EP 0860256, provides for:
- preparing a layer of granular material on a belt;
- taking such layer up by means of a drawer that is open underneath and whose bottom part is constituted by a permeable separator trough which a vacuum acts so as to support such layer raised;
- translating the drawer, and the relative contents, over the cavity of the mould and transferring the layer into the cavity by eliminating the vacuum.
[0003] This method has the advantage that different layers can be put one on another into the mould, in subsequent phases, without discomposing the arrangement of the layers. Nevertheless, this method has never been used in the ceramic industry for the fact that the raising of the layer by means of the vacuum is always incomplete and precarious. This causes remarkable and uncontrollable loading differences and unacceptable results, and also, in the case in which many layers are provided, such layers have to be loaded in subsequent phases with consequent considerable slowdown in production.
[0004] In a version of EP 0860256, on the layer's preparation surface, cavities are provided into each one of which is formed a decorated tile that has to be transferred, rigidly with the mould, by means of the vacuum device. This version, let to glimpse the possibility to transfer with a unique operation a coherent stratification constituted by a plurality of layers (decorated tile), but has many difficulties in carrying out.
[0005] The above said version entails, first of all, a considerable mechanical complication in constructing and in functioning due to the cavities.
[0006] Such version has, furthermore, many operating difficulties in loading the cavities and pressing the powders, also because it is necessary a perfect collimation and synchronization between the cavities and the loading and the pressing means.
[0007] In addition, such version does not enable a controlled insertion of the powder inside the cavities, most of all near the edges, for the fact that the powders have to necessarily fall on the bottom of the cavity and cannot be accompanied without discomposing.
[0008] The version does not enable to use continuous compacting means, such for example rolling cylinders or belts.
[0009] In addition, during the change, the substitution of heavy parts of the machine and the supply of remarkable manual interventions is requested.
[0011] EP 0997248 solves the problems said above, providing to feed the mould with all the layers in a single stroke, and providing to position a low permeability layer in the lower open part of the drawer, so as to make the raise and the transfer of the layers complete and very stable. This low permeability layer can be formed by a decal, by plastic material film, a layer of finer powder, by a pre-compacted layer, etc.
[0012] EP 0997248 offers many advantages also in relation to the others known mould-feeding methods, particularly for speed, constructional easiness, loading uniformity and checkability, for the possibility to arrange any kind of décor also very definite, etc., nevertheless EP 0997248 has in some cases functional limits that are hereinafter analyzed.
[0013] The glazed stoneware as imitation of natural stones, having veins going through all the thickness of the tile, can be pressed into two different manners.
[0014] In a first case, is provided that the visible side of the tile faces upward and, because in this case it is necessary a surface leveling of the layer by scratching, the aesthetic surface appearance is somewhat altered. To make the original aesthetic appearance visible, is thus necessary to remove a little surface layer, this is made in the smoothing phase.
[0015] This is an important limit because all the material produced has to be smoothed after firing, because the un-smoothed material is aesthetically very different and in any case uncouplable with the smoothed product; the problem is absolutely insuperable in the case in which the visible side is not flat but provided with reliefs.
[0016] Some artifice to overcome this inconvenience provide to pre-smooth all the green product before firing, or to remove by blowing and aspirating means the thin surface layer that has been altered by scratching, this in a phase occurring after mould-loading and before pressing. These are, in any case, expensive processes that are not devoid of inconveniences, such, for example, remarkable prolongations of the production cycle.
[0017] Really to overcome these inconveniences, in a second case is provided to operate with the visible side of the tile facing downwards, so that the leveling scratching does not alter the visible portion of the tile.
[0018] Nevertheless, if the feeding method provided in EP 0997248, is used, this second case has the same problems, because in the visible side of the tile (that faces downwards) a low permeability layer has to be provided (thinner powder o compacted layer) that is independent in relation with the remaining part and that thus determines in the thickness an interruption of the continuity of the aesthetical aspect.
[0019] As provided in EP 0997248, this inconvenience can be overcome by using a low permeability layer formed by a thin disposable film, this implies, in any case, a complication and an additional cost.
[0020] EP 0997248 provides to apply decorative layers on a base layer formed by loose granular material, and therefore can happen that these decorative layers do not remain perfectly stable or well defined really for the incoherence and roughness of the base layer. Furthermore the machines that can be used for applying decorations can not express their best for the presence of a base incoherent layer, not perfectly smooth and subjected to move if subjected to even stresses of limited entity.
[0021] An object of the invention is to improve the system for feeding the cavities of the pressing mould.
[0022] Another object of the present invention is to enable to feed the mould supporting and transferring the powders by vacuum, without necessary having an interruption in the lower stratifications and without disposable materials have to be used.
[0023] A further object, always in the field of feeding a mould supporting and transferring the powders by vacuum, is to enable a better application of surface decorative layers and an optimal use of decorator means.
[0024] A still further object is to improve the quality and the rapidity in transferring the powder material, especially in feeding a pressing mould.
[0025] A still further object is to simplify the machine construction, its functioning, and the format's change operations, in the feeding of a pressing mould with pre-compacted powders supported and transferred by vacuum.
[0026] A still further object is to better highlight the aesthetic surface effect of the pressed tile, without loosing productivity.
[0027] In a first aspect of the present invention, is provided a method for transferring granular material, comprising preparing on a surface layer means of said granular material arranged for forming at least a predominant part in the thickness of a tile, compacting said layer means on said surface, transferring said layer means by vacuum means, said preparing comprises preparing said stratification with exceeding dimensions in relation with the perimeter of said tile.
[0028] In a version, the method further comprises selecting a portion of said layer means substantially corresponding to the surface of said tile.
[0029] In a second aspect of the present invention is provided an apparatus for transferring granular material, comprising distributing means suitable for preparing layer means of said granular material on a surface arranged for forming at least a predominant part of the thickness of a tile, compacting means suitable for compacting said layer means on said surface, transferring means suitable for transferring said layer means by vacuum means, said distributing means being suitable for preparing on said surface said layer means with exceeding dimensions in relation with the perimeter of said tile.
[0030] In a version of the apparatus, are further provided selecting means suitable for selecting a portion of said layer means substantially corresponding to the surface of said tile.
[0031] In a third aspect of the invention, is provided a method for feeding with granular material a pressing mould for pressing tiles, said method comprising preparing layer means of said granular material on a surface, removing a surface layer of said layer means and transferring said layer means to said pressing mould.
[0032] In a fourth aspect of the invention, is provided an apparatus for feeding with granular material a pressing mould for pressing tiles, comprising distributing means suitable for preparing on a surface layer means of said granular material, removing means suitable for removing a surface layer of said layer means and transferring means for transferring said layer means to said pressing mould.
[0033] The invention will be better understood with the aid of the accompanying drawings that show some exemplifying and not limitative versions thereof, in which:
Figure 1 is a schematic side view of the apparatus according to the invention;
Figure 2 is a view like that one of Figure 1, in a different operating phase;
Figures 3, 4 and 5 are section enlarged view of the detail in the box A of Figure 2, showing different kinds of tiles that can be obtained at the end of the pressing phase;
Figures 6 and 7 are view like those of Figure 1 of a different version of the apparatus according to the invention, into two different operating phases.
[0034] The apparatus comprises a belt 1 permeable, wound on moving rollers 2, in the upstream part thereof, not shown, distributing means are provided for distributing granular material that are suitable for forming a stratification 3 arranged for constituting all the thickness S (or in any case a relevant part of the thickness S) of a tile 4.
[0035] As granular material has to be understood a loose material formed by granules that can be atomized or not, and that can have any dimension and shape, powder, chips, granules in different colors, having a surface or complete coloration etc., in any combination end not only for ceramic use.
[0036] The apparatus comprises a compacting station 5, in which compacting means acts on said stratification 3 so as to significantly reduce its initial thickness S1 to a value S2. The compacting means comprises a body 6 having an active surface, which is flat and is provided with a joined peripheral bevel 6a, slightly wider in relation to the surface of the tile 4, the body 6 acts in direction F during a stop phase of the indexing with a step P, of the belt 1. Any other compacting method can be used, for example a continuous type method using rollers, belts, swinging body with convergent active surface etc.
[0037] The value of the compacting pressure is advantageously limited, depending on the kind of granular material, in an order of magnitude comprised between about 0,5 and 5 bar, this implying to reduce the thickness from S1 to S2, with a value of the ratio S2/S1 comprised between about 0,75 and 0,9. Such compacting, with a so reduced entity is particularly easy to be obtained, because it does not require expensive machines to be used, and does not necessary implies containing means to be used for laterally containing the granular material 3.
[0038] In a following station T is carried out the removal of that compacted stratification by means of a depressor device 7 provided with a movable drawer 8, that is open underneath laterally delimited by a frame 9 that protrudes downward and that is suitable for penetrating into the stratification 3.
[0039] The bottom of this movable drawer 8 is formed by a permeable separator 10 communicating with a chamber 11 into which is activated vacuum during the raising and transferring towards the mould 12 phases, this vacuum being then deactivated for obtaining the gravity transferring into the cavity of the mould 12. This vacuum can be advantageously limited to a value of about 500-2000 Pa (50-200 mm water column) so ad to easily support a thickness S2 of about 15-20 mm of pre-compacted granular material 3.
[0040] The mould 12 is formed by a lateral matrix 13 and by half-moulds 14 movable that can translatory move in the vertical direction W; any other kind of mould can be in any case used.
[0041] The limited entity compacting - that has been previously described - enables an easy penetration of the frame 9 into the stratification and at the same time enables the complete and firm removal of the stratification 3 into the movable drawer 8. Owing to compacting said before it is furthermore possible to easy empty the movable drawer 8 simply due to the gravity force.
[0042] Unlike what has been described in EP 0997248, in which the supporting of the powder is obtained by the action of the atmospheric pressure acting on the lowest impermeable layer, in this case the vacuum acts more on the upper part of the stratification 3, whilst the lower parts of this stratification 3 remain grounded most of all for the effect of the little coherence between the granules induced by compacting.
[0043] It has to be highlighted that even said coherence is obtained by exerting a low entity pressure, the stability of the stratification 3 into the drawer 8 is very effective, also in presence of high accelerations because the different granules cannot move one in relation to another, and this enables high operating velocity of the apparatus.
[0044] Said coherence, obtained by exerting a low entity pressure, enables furthermore an easy recycling of the scraps 15 of granular material because said scraps becomes by a very low solicitation to the loose condition, therefore these scraps 15 can be directly recycled in the same plant. The scraps 15 can, for example be distributed in a thin uniform layer 16 over the stratification 13 already compacted, or can be distributed even more upstream at any level of the not yet compacted stratification 3.
[0045] The compacting can be carried out only on the parts of the stratification 3 arranged to be transferred, but the compacting can also be extended to all the stratification, thus enabling continuous compacting means to be used, because, moreover the scraps 15, even if compacted, are easily recyclable.
[0046] The compacting can be obtained by directly acting with the porous separator 10 that has been appropriately dimensioned and loaded, in this case the frame 9 have to project in respect to the porous separator 10 (if it is anchored in a relatively fixed manner to the porous separator 10) for an extension nearly corresponding to the thickness S2 that the stratification 3 will assume at the and of the compacting process.
[0047] Also in the other cases the frame 9 have to project in respect to the porous separator 10 for the same extension, plus an entity corresponding to the thickness of the further layers arranged after compacting.
[0048] The frame 9 can moreover be axially movable, in the operating phase, so as to take in relation with the plane of the porous separator 10 any suitable projection level.
[0049] In this case, can be selected before compacting phase the portion of the stratification 3 corresponding to the area of the tile 4: i.e. at first the frame 9 can be lowered towards the surface 1, so selecting and isolating a portion of stratification 3 substantially corresponding to the peripheral dimension of the tile 4, after will be lowered the porous separator 10 so as to compact, and by means of application of vacuum through the porous separator 10, the same compacting means 7, 9, 10 will execute the transferring towards the pressing station.
[0050] In a different version of the invention, shown in the Figures 6 and 7, the compacting means 5 is formed by a device provided with frame 22, substantially like that before described, whose pressing surface is formed by a surface 23 not necessary porous, and whose function is to select, compact and to leave on the surface 1 the compacted portion 24 of stratification 3 substantially corresponding to the peripheral dimension of the tile 4.
[0051] Such pressing device is described, for example in EP 0793565. The transferring towards the pressing station 12 of the compacted portion of stratification 3 is later on carried out by vacuum means 7. Therefore, as in the previous case, happens that the portion of stratification 3 corresponding to the area of the tile 4 is selected before the compacting phase.
[0052] A functional or decorative stratification 17 can be arranged, in station D arranged between the stations 5 and T, on the already compacted layer 3. This case could be useful, for example, for obtaining a double-face product, as shown in Figure 4, provided with a part 3 with prevailing thickness having uniform characteristics or in any case decorator elements 18 extending without interruption from one of the face 19 towards a zone 20 close to the other face 21. The other face 21 is instead formed by decorator materials 17 arranged in a relatively thinner stratification.
[0053] This procedure is not necessary limited to a double-face product, but it can be used also for obtaining having as visible side only the upper face 21 as shown in Figure 5. This would be useful in the case in which arranging the decorative layer 17 is easier or, in any case, more functional is effected on an already pre-compacted base, for example in order to obtain clearer decorations, or to use different applying techniques, even contact techniques, that otherwise be used or could be used with less efficiency.
[0054] The preparation surface can also be of type different from the belt 1, for example it could be formed by a sequence of permeable trays provided with chassis or not (walls for laterally containing the powders) integrated or movable, that are moved along a path like a loop with different stations for the various operations like distributing the powders, decorating, compacting, removing by vacuum, etc.
[0055] The belt 1 can be completely free as shown into the drawings, or it can be provided with frames (walls for laterally containing the powders).
[0056] Such chassis can be integrated to the same belt 1 and be advantageously flexible and woundable with the belt.
[0057] Such chassis can be simply leaned on the upper branch of the belt 1, so as to be removed after emptying and be arranged again on the upper branch of the belt 1 kin the initial tract.
[0058] Also such chassis leaned on the belt 1 and/or on the trays, could be transferred, in the transferring phase of the stratification 3 towards the mould 12, over the cavity of the mould 12 together with the vacuum device 7, to which the frames will be temporarily anchored, in this case the frame 9 of the vacuum device 7 can be omitted. Practically the chassis will become from time to time the frame 9 of the vacuum device 7.
[0059] Using systems provided with chassis for laterally containing the powders can make mechanically more complicated the plant, most of all in the case in which the plant is intended for producing different formats of tiles 4; this can nevertheless avoid the formation of the scraps 15 of powders and make subsequently un-necessary the plant for recovering such scraps.
[0060] As it has been already said, the surface 1 can be indexed or it can be continuously moved, also in the drawing phase, because the drawer 8 during the drawing phase can be advantageously synchronously follow the motion of the surface 1.
[0061] The invention can be applied not only in the fabrication of decorated tiles in the pressing phase, but also in the fabrication of non-decorated tiles or in the fabrication of tiles that are decorated in a subsequent glazing. This can result advantageous in order to speed up the mould's loading, to obtain a high loading uniformity, to reduce wears of the mould due to friction with a traditional grid-trolley etc.
[0062] Compacting the surface 1, if necessary, can also be of widely greater entity in respect to that indicated, for example it could also reach values greater that 200 bar. In this case, the stratification 3 can be transferred to the mould 12 by a vacuum means 7 without the frame 9, as shown in the Figures 6 and 7, because said stratification is per se sufficiently coherent; the stratification 3 to be transferred has a measure corresponding to the dimension of the tile 4 to be obtained, or it can have also a wider extension so as to be, for example, cut to length in the initial pressing phase of the mould 12 according to known methods as described for example in IT 01287505.
[0063] Therefore, in this last case, happens that the phase of selecting a portion of the stratification corresponding to the area of the tile 4 is subsequent to the phase of transferring towards the pressing station, because the selecting means (12, 13, 14) arranged downstream the transferring means (7, 8, 9, 10, 11).
[0064] When the compacting of the stratification 3 has sufficient high entity, as before described, and on the stratification 3 have not been distributed further incoherent layers 16, 17, the vacuum device 7 can also be constituted by elements cooperating only with one or more portions of the surface of said compacted stratification 3, i.e. the porous separator 10 could be substituted by a plurality of suckers distributed in a plane.
[0065] As highlighted in the Figure 1 and 2, the stratification 3, before the compacting phase is subjected to a removing operation for removing a thin surface layer S3 by aspirator means 25. This operation is useful for better highlighting the surface aspect of the stratification, because such aspect can have been altered by the friction against leveling means 26.
[0066] Such removing, according to the different case, can affect a thickness S3 higher or thinner, comprised for example between 0,2 and 4 mm.
[0067] Such removing can affect a surface layer having a substantial uniform thickness S3 and extending at least as the portion of the stratification 3 arranged to be transferred to the mould 12.
[0068] It is important that this removed thickness S3 is as uniform as possible so as to support constant the thickness S1 and not to causes differences in loading the mould 12.
[0069] This surface removing can be executed also with other means, for example, with the aid of a light blowing, as provided in WO 02/09917, or by a vacuum acting through permeable screen means, as provided in EP 0927687. The surface drawing so highlighted, will not be subjected to substantial alterations in the following phases, and will appear almost unchanged on the surface of the pressed tile 4.
[0070] According to the present invention, this surface removing of the stratification 3, that occurs in a station R arranged upstream the pressing station 12, it is not limited to the example shown in the Figures 1 and 2, but can be applied in all the systems that provides to transfer a stratification from a preparation surface 1 to a pressing mould 12, without discomposing said stratification 3.
[0071] This surface removing is not limited to the presence of the compacting on the preparing surface 1. So, for example, this surface removing of the stratification 3 can be used in a transferring system with a vacuum cavity open underneath that advantageously cooperates with a low permeability base layer, as provided in EP 0997248.
[0072] It has to be highlighted that this process is extremely advantageous in relation to what is provided in WO 02/09917, in which, because this operation is carried out into the mould in a phase subsequent to loading, a remarkable extension of the production cycle occurs.
[0073] In the process according to the present invention, this does not implies any slowdown of the production cycle.
[0074] It has to be highlighted that compacting, in agreement with one of the objects of the invention, enables to accelerate the production cycle, even for the fact that the transferring can be executed with high accelerations, and also for the fact that in the subsequent pressing less de-aerating time is requested.
[0075] It has to be specified that the compacted stratification 3, arranged for constituting the main part of the thickness S of the tile 4, can constitute a percentage of the thickness S comprised between 50% and 100%, advantageously between 80% and 100%.
1. Method for transferring granular material (3, 16, 17, 18), comprising preparing on
a surface (1) layer means (3) of said granular material (3, 16, 17, 18) arranged for
constituting at least a main part of the thickness (S) of a tile (4), compacting said
layer means (3) on said surface (1), transferring said layer means (3) by vacuum means
(8), said preparing comprising preparing said layer means (3) with the sizes exceeding
the perimeter of said tile (4).
2. Method according to claim 1, wherein said preparing comprise remove a surface layer
(S3) of said layer means (3).
3. Method for feeding with granular material (3, 16, 17, 18) a pressing mould (12) of
tiles (4), comprising preparing on a surface (1) layer means (3, 16, 17, 18) of said
granular material (3, 16, 17, 18), removing a surface layer (S3) of said layer means
(3, 16, 17, 18) and transferring said layer means (3, 16, 17, 18) to said pressing
mould (12).
4. Method according to claim 3, and further comprising compacting said layer means (3)
on said surface (1).
5. Method according to claim 3, or 4, wherein said transferring comprises transferring
said layer means (3) by vacuum means (8).
6. Method according to any one of claims 3 to 5, wherein said preparing comprises preparing
said layer means (3) having dimensions exceeding the perimeter of said tile (4).
7. Method according to any one of the preceding claims, and further comprising selecting
a portion of said layer means (3) substantially corresponding to the area of said
tile (4).
8. Method according to claim 7 as appended to claim !, or 2, or 4, or to claim 5, or
6 as appended to claim 4, wherein said selecting occurs after said compacting and
before said transferring.
9. Method according to claim 1, or 2, or 4, or according to any one of claims 5 to 8
as appended to claim 4, wherein said compacting comprises compacting with means (6)
that not necessary interrupt the continuity of said layer means (3).
10. Method according to claim 1, or 2, or according to claim 5 as appended to claim 4,
or according to any one of claims 6 to 9 as appended to claims 4 and 5, wherein said
compacting comprises acting with a surface (10) of said vacuum means (8).
11. Method according to claim 1, or 2, or claim 4, or according to any one of claims 5
to 10 as appended to claim 4, wherein said compacting comprises subjecting said layer
means (3) to a pressure comprised between 0,5 and 5 bar.
12. Method according to claim 1, or 2, or claim 4, or according to any one of claims 5
to 11 as appended to claim 4, wherein said compacting causes a reduction of the thickness
of said layer means (3) from a value (S1) to a further value (S2), the ratio between
said value and said further value (S2/S1) being comprised between 0,75 and 0,9.
13. Method according to any one of the preceding claims, wherein said transferring comprises
supporting said layer means (3) with a vacuum comprised between 500 and 2000 Pa.
14. Method according to claim 1, or 2, or 5, or according to any one of claims 6 to 13
as appended to claim 5, wherein, being said surface (1) movable, said transferring
comprises moving said vacuum means (8), at least in a phase, with direction and velocity
concordant with the direction and the velocity (P) of said surface (1).
15. Method according to any one of the preceding claims, wherein said preparing comprises
depositing a thickness of said layer means (3) constituting at least the 50% of the
thickness of said tile (4).
16. Method according to any one of the preceding claims, wherein said preparing comprises
depositing a thickness of said layer means (3) constituting at least the 80% of the
thickness of said tile (4).
17. Method according to any one of claims 2 to 6, or according to any one of claims 7
to 16 as appended to any one of claims 2 to 6, wherein said removing comprises removing
a surface layer (S3) having an extension substantially at least corresponding to the
extension of a tile (4).
18. Apparatus for transferring granular material (3, 16, 17, 18), comprising distributing
means suitable for preparing on a surface (1) layer means (3) of said granular material
(3, 16, 17, 18) arranged for constituting at least a main part (S) of a tile (4),
compacting means (5, 6, 10, 23) suitable for compacting said layer means (3) on said
surface (1), transferring means (7, 8, 9, 10, 11) suitable for transferring said layer
means (3) by vacuum means (8), said distributing means being suitable for preparing
on said surface (1) said layer means (3) having a size exceeding the perimeter of
said tile (4).
19. Apparatus according the claim 18, and further comprising removing means (R, 25) suitable
for removing a surface layer (S3) of said layer means (3, 16, 17, 18).
20. Apparatus for feeding with granular material (3, 16, 17, 18), a pressing mould (12)
of tiles (4), comprising distributing means (26) suitable for preparing on a surface
(1) layer means (3, 16, 17, 18) of said granular material (3, 16, 17, 18), removing
means (R, 25) suitable for removing a surface layer (S3) of said layer means (3, 16,
17, 18), and transferring means (7, 8, 9, 10, 11) for transferring said layer means
(3, 16, 17, 18) towards said pressing mould (12).
21. Apparatus according to claim 20, and further comprising compacting means (5, 6, 10,
23) suitable for compacting said layer means (3) on said surface (1).
22. Apparatus according to claim 20, or 21, wherein said transferring (7, 8, 9, 10, 11)
comprises vacuum means (8).
23. Apparatus according to any one of claims 20 to 22, wherein said distributing means
are suitable for preparing on said surface (1) said layer means (3) with dimensions
exceeding the perimeter of said tile (4).
24. Apparatus according to any one of claims 18 to 23, and further comprising selecting
means (9, 12, 13, 14, 22) suitable for selecting a portion of said layer means (3)
substantially corresponding to the area of said tile (4).
25. Apparatus according to claim 24 as appended to claim 18, or 19, or 21, or to claim
22, or 23, as appended to claim 21, wherein said selecting means (9) are arranged
downstream of said compacting means (5, 6) and upstream of said transferring means
(7, 8, 9, 10, 11).
26. Apparatus according to claim 18, or 19, or 21, or according to any one of claims 22
to 25 as appended to claim 21, wherein said compacting means (5, 6) does not necessary
interrupt the continuity of said layer means (3)
27. Apparatus according to claim 18, or 19, or 22 as appended to claim 21, or according
to any one of claims 23 to 26 as appended to claims 21 and 22, wherein said compacting
means (5, 6, 10, 23) comprises a surface (10) of said vacuum means (8).
28. Apparatus according to claim 18, or 19, or 21, or according to any one of claims 22
to 27 as appended to claim 21, wherein said compacting means (5, 6, 10, 23) exerts
a pressure comprised between 0,5 and 5 bar.
29. Apparatus according to claim 18, or 19, or 22, or according to any one of claims 23
to 28 as appended to claim 23, wherein said vacuum means (8) creates a pressure comprised
between 500 and 2000 Pa.
30. Apparatus according to claim 18, or 19, or 22, or according to any one of claims 23
to 29 as appended to claim 22, wherein, being said surface (1) movable, said vacuum
means (8) can be operated, at least in a portion, concordantly with the motion of
said surface (1).
31. Apparatus according to any one of claims 19 to 23, or according to any one of claims
24 to 30 as appended to any one of claims 19 to 23, wherein said removing means are
conformed so as to remove a surface layer (S3) having an extension substantially at
least corresponding to the extension of a tile (4).