IE20010590A1

IE20010590A1 - Method and apparatus for producing flat ceramic articles with full-thickness decorations

Info

Publication number: IE20010590A1
Application number: IE20010590A
Authority: IE
Inventors: Stefano Caroni
Original assignee: Kestro Internat Limlited
Priority date: 2001-06-26
Filing date: 2001-06-26
Publication date: 2002-12-30
Also published as: EP1270160A1; MXPA02006354A; CN1393325A; BR0202396A

Abstract

A method for manufacturing flat ceramic articles with full-thickness decorations, characterized in that it comprises the steps of taking, according to a predefined sequence, calibrated doses of material in powdery/atomized form from storage means, introducing to a predefined sequence, the calibrated doses into at least one means for forming that articles by compaction which is provided with one or more vertical flat receptacles, removing the articles formed by compaction and sending them to pressing for permanent stabilization. <Figure 3>

Description

The present invention relates to a method and an apparatus for producing flat ceramic articles with full-thickness decorations.

The ceramics industry is constantly seeking articles which are capable of attracting market attention while containing production costs, yet have highvalue organoleptic features.

The manufacture of articles made of porcelain stoneware is part of this context; this material is easily industrially workable for providing shapes and decorations which are highly appreciated and is also highly resistant to the attack of external atmospheric and other agents.

As part of such search, attempts are being made to reproduce, using this material, also components which visually have the characteristics of natural stone, such as marble and others; accordingly, ^research is concentrating its efforts in this direction.

In the reproduction of natural materials, one of the main characteristics to be reproduced is constituted by the veins of the materials, which also penetrate with continuity the innermost regions.

Moreover, such veins have absolutely random arrangements, although they are substantially continuous in their extension, and achieving these characteristics in industrially manufactured articles is the result which, as mentioned, ceramics research is seeking.

Besides the above mentioned characteristics, the articles must also be able to have a rough appearance, as if they had been obtained manually by skilled stonecutters by using such natural materials.

In summary, the more articles manufactured with industrial cycles organoleptically resemble handicraft ones, the more they increase in value and are sought after.

In order to achieve these results, some manufacturing processes have been devised by means of which, however, it is possible..fo...manufacture articles which imitate with greater perfection the external features of natural materials but unmistakably reveal their industrial manufacture internally, i.e. just below the exposed surface.

These articles are manufactured, for example, by using preformed pads, usually made of high-strength plastics, which form a negative impression of the appearance of the several natural stones and are inserted in the molds of the presses, transferring their negative impression as a positive shape onto the material loaded inside the dies of the molds; this method also allows to vary the thickness of the several fillers, optionally providing a bed of lowvalue material designed to become the laying face of the articles on which one or more successive loading operations deposit one or more layers of materials designed to constitute the visible faces of the articles and onto which the pads activated during the pressing cycle descend.

However, the resemblance with articles obtained directly from natural materials is still very approximate, especially as regards, as mentioned, the internal portion of the article.

The aim of the present invention is to provide a method and an apparatus for manufacturing flat ceramic articles with full-thickness decorations which allows to manufacture ceramic articles having all the characteristics of those obtained directly from natural materials.

Within this aim, an object of the present invention is to provide a method and .an apparatus for manufacturing flat ceramic articles, with full-thickness decorations which allow to obtain, with industrial methods, flat ceramic articles of any plan size and thickness.

This aim and this and other objects which will become better apparent hereinafter, are achieved by the present method for manufacturing flat ceramic articles with full-thickness decorations, characterized in that it comprises the steps of: taking, according to a predefined sequence, calibrated doses of material in powdery/atomized form from storage means, introducing, according to a predefined sequence, said calibrated doses into ίΐ $ at least one means for forming the articles by compaction which is provided with one or more vertical flat receptacles, removing the articles formed by compaction and sending them to pressing for permanent stabilization.

Advantageously, the apparatus for manufacturing flat ceramic articles with full-thickness decorations is characterized in that it comprises a storage system for the accumulation and calibrated distribution of powdery/atomized materials which can be connected to at least one modular unit for forming the articles by compaction which is provided with one or more vertical flat receptacles and can be connected downstream to a means for conveying the formed articles towards at least one presser means for permanent stabilization of said articles formed by compaction.

Further characteristics and advantages of the present invention will become better apparent from the detailed description of a preferred but not exclusive embodiment of a method and an apparatus for manufacturing flat ceramic articles with full-thickness decorations, illustrated only by way of non-limitative example in the accompanying drawings, wherein: Figure 1 is a schematic general view of an apparatus for manufacturing flat ceramic articles with full-thickness decorations according to the invention; Figure 2 is a schematic general view of the apparatus of Figure 1, to which a station for cutting the formed articles has been added; Figure 3 is an enlarged-scale detail,yiew of a modular unit for forming the articles by compaction which is part of the invention.

With reference to the figures, the reference numeral 1 generally designates an apparatus by means of which it is possible to produce flat ceramic articles M which have full-thickness decorations.

The apparatus 1 comprises a storage system 2 for the accumulation and calibrated distribution of materials in powdery or atomized form, which in its practical embodiment can be connected to a battery of modular units 3 which are arranged in parallel and are adapted to form the articles M by Ρ ίζ compaction; each one of the modular units 3 has at least one vertical flat receptacle 4.

Each unit 3 can further be connected downstream to a means 5 for conveying the formed articles towards a presser means 6 for the final stabilization of the articles M formed by compaction.

Each modular unit 3 for forming the articles M by compaction comprises a box-like frame 7 having, in the preferred embodiment shown in Figure 3, in an upward region and in a downward region, two pairs of openings, respectively an opening 8 for loading the materials and an opening 9 for unloading the formed articles.

Two vertical pads 10 and two respective vertical contrast pads 11 are mounted inside each frame 7 so that they can slide horizontally; the vertical flat receptacles 4 are formed between said pads and contrast pads and the internal walls of the box-like frame 7.

In particular, the loading opening 8 and the unloading opening 9 lie on mutually staggered vertical planes but are arranged symmetrically with respect to an imaginary central vertical plane whose outline is designated by P.

In detail, the vertical planes of arrangement of the openings 9 for unloading the formed articles substantially coincide with the vertical planes of arrangement of the inlet fronts of each conveyance means 5.

Each pad 10 can move, by way of respective actuators 12 and so as to be guided inside the box-like frame 7 e.g. by means of pairs of rods 7a, both with respect to the respective contrast pad 11 for forming the articles by compaction and synchronously therewith in order to move between a first position for alignment between the receptacle 4 and the vertical plane of arrangement of a loading opening 8 and a second position for the alignment of the receptacle 4 with the plane of arrangement of the opening 9 for unloading the formed articles, and vice versa.

Each loading opening 8 forms upstream a small hopper 13 for collecting η κ η 8 the material fed by the accumulation storage system 2.

As mentioned, each box-like frame 7 accommodates two pairs of pads 10, 110 and contrast pads 11, 111 and their actuation is alternated, while the movements between the above two positions are synchronous and opposite one another; in this manner, each pair is served by its own loading opening 8 and its own unloading opening 9.

Moreover, the receptacles 4,104 of the pairs of pads 10,110 and contrast pads 11, 111 can be alternately and simultaneously positioned, with alternating cycles, so as to be aligned with the respective loading opening 8 of one pair and unloading opening 9 of the other pair, and vice versa.

The accumulation and distribution storage system 2 comprises modular silos 14 for containing powdery or atomized materials being strictly monochrome; the outlets 15 lead onto a means 16 for conveying and routing calibrated doses of said monochrome materials taken from the silos 14 and deposited first in a mixing unit 116 and then from there into containers 17 of materials which are mixed in a plurality of colors.

The means 5 for conveying the articles M comprises pairs of ramps of first conveyors 18 with facing active portions 19, between which an opening 20 is provided which forms a substantially constant clearance being in any case smaller than the thickness of the formed articles M; the articles M are contained and conveyed between the active portions 19, and the first conveyors 18 have inlet fronts 18a- substantially vertically aligned with the respective unloading openings 9, while the outlet fronts 21 can be arranged so as to face, substantially without discontinuities, the contiguous inlet fronts 22 of second conveyors 23 for connection to the presser means 6.

Since in the preferred embodiment of the invention the conveyance means 5 are vertical and the second connection conveyors 23 are horizontal, between the outlet fronts 21 and the inlet fronts 22 there are provided interposed portions 24 of pairs of facing connecting conveyors 25 which can be overturned on vertical planes and along horizontal axes from a position η ii which is aligned coaxially to the pairs of first conveyors 18 and a position which is aligned coaxially to second conveyors 23 and vice versa.

If required by the type of articles M, at least one station 26 for decorating the exposed faces of the formed articles M can be interposed in the apparatus 1 between said conveyance means 5 and the presser means 6.

Moreover, ahead of the presser means 6, a station 27 for cutting the formed articles M into portions having predefined planar dimensions, can be arranged.

The method for manufacturing flat ceramic articles with full-thickness decorations and the operation of the corresponding apparatus are as follows: materials in the powdery or atomized state, having basic organoleptic characteristics such as a single color, are accumulated in the silos 14.

According to an electronic management program which automatically controls the apparatus 1, predefined doses of such materials are taken from the silos 14 and are unloaded through the outlets 15 onto the conveyor 16, from which they reach the containers 17 after passing through the mixing unit 116, in which they are introduced in predefined percentages so as to constitute multicolored mixtures.

From the containers, such mixtures pass into the batteries of modular units 3 for forming the articles M.

In the preferred embodiment, the two pairs of pads 10, 110 and contrast .pads. 11, ,111, between which the vertical receptacles. 4, 104 for actual forming of the articles M by compaction are formed, are active in each one of the modular units 3.

During the loading of materials, the first pair formed by a pad 10 and a contrast pad 11 is arranged inside the box-like frame 7 so that its receptacle 4 is vertically aligned with the loading opening 8, which is advantageously provided with a collection hopper 13.

At the same time, the second pair formed by the pad 110 and the contrast pad 111, which can move rigidly with the preceding one on the rods 7a, is ft c 9 0 h ΐ Ή arranged so as to vertically align its receptacle 104 above the unloading port 9.

Substantially, when the operating cycle is in the steady state, this positioning allows to load one receptacle, e.g. the receptacle 4, of the pair constituted by the pad 10 and the contrast pad 11 through its opening 8 being aligned therewith, and simultaneously to expel an article M which is formed by the other pair constituted by the pad 110 and the contrast pad 111 through its unloading opening 9.

During the loading of the receptacle 4 (or 104), the powdery or atomized materials are unloaded into it according to a predefined layering and therefore with different colorings which, upon compaction, become the veins that decorate the articles M fully across their thickness.

When the receptacle 4 (or 104) is fully loaded with material, the actuator 12 actuates the corresponding pad 10 (or 110) in order to compact it against the contrast pad 11 (or 111) and thus form an article M; the compaction force is understood to be sufficient to maintain the cohesion of the compacted material in the form of a flat article M.

Simultaneously, the actuator 112 actuates the opening of the pad 110 (or 10) with respect to the contrast pad 111 (or 11), releasing the formed article M, which is unloaded towards the underlying conveyance means 5.

In detail, the unloaded article M is clamped between the underlying active portions 19 of the firstconveyors 18 and is made.lo descend, until it reaches the corresponding portion 24.

Such portion rotates and moves from a position which is aligned with the active portions 19 and is vertical to a position which is co-planar with respect to the second conveyor 23, onto which the article M is transferred and sent towards the presser means 6 for permanent stabilization of its structure.

During transfer towards the presser means 6, if required by production, the article M can be decorated by passing it through a corresponding decoration station 26 advantageously arranged along the extension of the conveyor 23.

Alternately, each formed article M can be subjected to one or more decorative applications on the exposed face, which are performed directly inside the receptacles 4 or 104; such receptacles can in fact be additionally loaded with material after a slight and calibrated reopening of the pads 10, 110 without however expelling the article M already formed inside them, i.e. so as to produce between the exposed face of the article and the pads 10, 110 (or also the contrast pads 11, 111) a vertical laminar gap to be filled with a second charge (or more than one charge) to be compacted with a second action (or, correspondingly, even more than one action in the case of more than two charges). The second charge, by means of a new compaction, becomes the exposed decorative surface of the article M before the article is expelled through the openings 9.

Moreover, again according to production requirements, the formed articles M can also be divided into portions by providing, along said conveyor 23, a cutting station 27 optionally upstream of the decoration station 26, if provided.

Likewise, inside the presser means 6, the opposite operation can be performed, i.e. arranging mutually side by side, in the conventional receptacle thereof, a plurality of formed articles M and packing them monolithically, by pressing, into a single multiple article M, - In practice it has been observed that the described invention achieves the intended aim and objects.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims.

All the details may further be replaced with other technically equivalent ones.

In practice, the materials used, as well as the shapes and the dimensions, may be any according to requirements without thereby abandoning the scope of the protection of the appended claims.

Claims

1. A method for manufacturing flat ceramic articles with full-thickness decorations, characterized in that it comprises the steps of taking, according to a predefined sequence, calibrated doses of material in powdery/atomized form from storage means, introducing, according to a predefined sequence, said calibrated doses into at least one means for forming the articles by compaction which is provided with one or more vertical flat receptacles, removing the articles formed by compaction and sending them to pressing for permanent stabilization.

2. The method according to claim 1, characterized in that a step for decorating the exposed surfaces of the formed articles is provided ahead of said pressing for permanent stabilization.

3. The method according to claim 1, characterized in that between the removal of the articles formed by compaction and the pressing for final stabilization, during the step for sending the formed articles towards said pressing, the formed articles are divided into dimensionally predefined portions.

4. The method according to claim 1, characterized in that between the removal of the articles formed by compaction and the pressing for final stabilization, during the step for sending the articles towards said pressing, a plurality of formed articles are packed into single multiple articles which can be stabilized monolithically and permanently with said subsequent pressing.

5. The method according to claim 1, characterized in that the introduction in a predefined sequence of said calibrated doses into said article forming means and said compaction for forming the articles can both be repeated for each formed article.

6. An apparatus for manufacturing flat ceramic articles with fullthickness decorations, characterized in that it comprises a storage system for the accumulation and calibrated distribution of powdery/atomized materials, which can be connected to at least one modular unit for forming the articles by compaction which is provided with one or more vertical flat receptacles and can be connected downstream to means for conveying the formed articles towards at least one presser means for permanent stabilization of said articles formed by compaction.

7. The apparatus according to claim 6, characterized in that said modular unit for forming the articles by compaction comprises a box-like frame being provided, in an upward region and in a downward region, with openings respectively for loading powdery/atomized materials and for unloading the formed articles, a vertical pad and a vertical contrast pad being mounted inside said frame so that they can slide horizontally, said one or more vertical flat receptacles being formed between said pads and the internal walls of said box-like frame.

8. The apparatus according to claim 7, characterized in that said loading and unloading openings are arranged on mutually staggered vertical planes.

9. The apparatus according to claims 7 and 8, characterized in that the vertical plane of arrangement of said opening for the unloading of the formed articles substantially coincides with the vertical plane of arrangement of the inlet front of said conveyance means.

10. The apparatus according to claim 7, characterized in that said pad and contrast pad can move by way of respective actuators which are guided inside, .said, box-like frame with respect lo each other in order to form the articles by compaction and synchronously between a first position for the alignment of said one or more receptacles with the vertical plane of arrangement of said loading opening and a second position for aligning said one or more receptacles with the plane of arrangement of said opening for unloading the formed articles and vice versa.

11. The apparatus according to claims 7, 8 and 10, characterized in that said loading opening forms upstream a small hopper for collecting the material fed by said accumulation storage system.

12. The apparatus according to claims 7 to 11, characterized in that said pad and contrast pad are at least two pairs, are accommodated in each boxlike frame and are actuated alternately with synchronous and opposite movements, each pair being served by its own loading opening and unloading opening which are arranged symmetrically in said box-like frame with respect to a central vertical plane.

13. The apparatus according to claim 12, characterized in that the receptacles of said pairs of pads and contrast pads can be arranged alternately and simultaneously, with alternated cycles, so that they are aligned with the respective loading opening of one pair and unloading opening of the other pair and vice versa.

14. The apparatus according to claim 6, characterized in that said accumulation and distribution storage system comprises modular silos for containing powdery/atomized monochrome materials with outlets which lead onto a means for the conveyance and routing of calibrated doses of said monochrome powdery/atomized materials into containers for powdery/atomized materials mixed in a plurality of colors.

15. The apparatus according to claims 6 to 10, characterized in that said article conveyance means comprises pairs of ramps of first conveyors with facing active portions, between which there is provided an opening which has a substantially constant clearance being smaller than the thickness of the formed articles, for containing and conveying, said articles, their inlet, fronts being aligned vertically with the respective unloading openings of said boxlike frame, their outlet fronts being arrangeable so as to face, substantially without discontinuities, the contiguous inlet fronts of second conveyors for connection to said stabilization presser means.

16. The apparatus according to claim 15, characterized in that portions of pairs of facing connection conveyors are interposed between the outlet fronts of said pairs of first conveyors and the inlet fronts of said second conveyors and can be turned over on vertical planes and along horizontal axes from a position which is aligned coaxially with said pairs of first conveyors to a position which is aligned coaxially with second conveyors and vice versa.

17. The apparatus according to claims 6, 15 and 16, characterized in that 5 said pairs of first facing conveyors are arranged vertically below said boxlike containment frame, in alignment with said formed article unloading openings.

18. The apparatus according to claim 6, characterized in that at least one station for decorating the exposed faces of the formed articles is interposed io between said conveyance means and said presser means.

19. The apparatus according to claim 6, characterized in that a station for cutting the formed articles into portions having predefined planar dimensions is arranged ahead of said presser means.