PROCESS FOR TARSIA-WORKING OF MARBLE, GRANITE, ETC.

Abstract: The process according to the invention comprises a first step in which the material which is intended to form the support (12) for a tarsia decoration is worked by means of a digitally controlled (DC) milling machine which is programmed in such a way as to obtain, by means of diamond-tools acting on the surface to be decorated, areas which reproduce, by means of grooves (14) and notches, a decoration pattern. A slab (11) constituted by the material forming the decoration is then worked by means of a DC milling machine in order to form on the slab, in relief, a decoration pattern. Said slab (11) is then placed on the material (12) to be decorated, in the grooves of which a suitable bonding agent is previously laid down, in such a way as the reliefs are embedded in said grooves. Then, the upper portion of such a sandwich is removed, normally by means of a longitudinal cut, thereby freeing the decorated material, which is successively smoothed and polished.

Description: PROCESS FOR TARSIA-WORKING OF MARBLE, GRANITE ETC. * * * * * The present invention relates to a process for tarsia-working of materials such as marble, stone or grani te. More particularly, the present invention relates to a process allowing a tarsia decoration of any shape and/or size to be obtained on blocks, panels or slabs made of stone-like material in a quick and economical way, said process being able to be continuously reproduced on industrial scale. Furthermore, the invention relates to a material such as marble, stone or granite provided with a tarsia decoration obtained by means of such process. The invention may be mainly applied in the field of marble, stone, granite and similar materials workin industry. Several methods are known in the art for obtaining tarsia decorations on a surface. According to the traditional method for tarsia- working of stone-like materials, which is known since ancient times, the decoration supporting surface is hand-milled in order to obtain grooves and/or notches suitable for housing the elements forming the decoration, which are individually obtained by manually cutting and milling small material blocks. Each of the elements forming the decoration is then laid down on the supporting surface and glued to the lat ter . Finally, the decorated surface is further treated, by means of polishing, sandblasting operations etc.. This working method involves several disadvantages and drawbacks, since it is extremely dispersive in terms of time and costs which are needed for laying down the 5 decorated surface. According to another method, which is mainly used for obtaining relatively thin tarsia-decorated slabs, the slab to be decorated is firstly worked by means of an automatic machine of a type which is commonly - Q designated as "water-jet machine", which deeply digs the stone-like material by means of a very thin water jet which is mixed with suitable abrasive powders and which is sent at a very high pressure, until an element having a predetermined shape may be detached from the slab. 15 The process is continuously repeated for each slab and decoration element, and finally the elements are laid down on a suitable support and assembled on it like a mosaic by glueing the elements to the support by means of resins or bonding agents. 20 Finally, the decorated slab undergoes suitable treatments, such as smoothing, polishing etc.. This method also involves several drawbacks and disadvantages in terms of time and costs, which are essentially due to the necessity of individually laying 25 down with great accuracy the decorated elements on the supporting base, such as in mosaic-workings. The present invention aims to obviate to the disadvantages and drawbacks which are typical of the background art, and to provide, thus, for a a process 30 for tarsia-working of stone-like materials such as marble, stone, granite and similar materials, said process being reliable and very simple to be carried out, and which allows tarsia-decorated products reproduceable on industrial scale to be obtained, thereby substantially reducing the production times which are necessary by means of the known methods. 5 This is achieved by means of a process having the features disclosed in the main claim. The dependent claims disclose advantageous forms of embodiment of the invention. Furthermore, the invention relates to tarsia- 10 decorated products made of a stone-like material which are obtained by means of such process. The process according to the invention comprises a first step in which the material which is intended to form the support for the tarsia decoration is worked by 15 means of a digitally controlled (DC) milling machine which is programmed in such a way as to obtain, by means of diamond-tools acting on the surface to be decorated, areas which reproduce, by means of grooves and notches, the decoration pattern. 20 A slab constituted by the material forming the decoration is then worked by means of a DC milling machine in order to form on the slab, in relief, the decoration pattern. Said slab is then placed on the material to be 25 decorated, in the grooves of which a suitable bonding agent is previously laid down, in such a way as the reliefs are embedded in said grooves. i Then, the upper portion of such a sandwich is removed, normaly by means of a longitudinal cut, thereby < * 30 freeing the decorated material, which is successively smoothed and polished. It is apparent that the process according to the invention may be carried out for any decorative pattern, in accordance with the program instruction which are input in the DC machine tool. Other features and advantages of the invention will become apparent by reading the following description, of a form of embodiment of the invention, given as a non- limiting example, with the help of the figures illustrated in the attached sheet, in which: - figure 1 shows a plan view of a tarsia-worked tile made of a stone-like material; - figure 1 shows a section along line A-A of fig. 1; - figure 3 shows, in a side section, a step of the working process according to the invention, and - figure 4 shows, in a side section, a following step of the process according to the invention. In the figures, reference sign 10 generally indicates a tarsia worked tile made of a styone-like material, e.g. marble, stone, granite or similar material . Said tile 10 essentially comprises a decoration 11 made of a stone-like material, which is inserted in suitable grooves or notches machined in a slab 12, also made of a stone-like material (see fig. 2). According to the invention, tile 10 is obtained by means of the following process. A first slab 12 is machined by means of a DC milling machine in order to obtaine, by means of diamond tools, a series of notches and/or grooves 14 reproducing the drawing of the decorative pattern. Similarly, a second slab 11 is machined by means of a DC milling machine in order to obtain, in relief, the decrorative pattern 13. Thereafter, a layer of suitable bonding agent or resin is laid down on notches 14, and slab 11 is fittingly placed on slab 12, in such a way that reliefs 13 are accomodated into grooves 14 (figs. 3 and 4); slab 11 undergoes a pressure F acting in the direction of slab 12. Once the boding agent has completed its action, the sandwich formed by slabs 11, 12 is longitudinally cut along line C-C. The resulting product is a tile formed by slab 12 and provided with a tarsia decoration constituted by the material of slab 11 (fig. 2) As it may remarked from the preceding description, the process according to the invention allows large quantities of products made of stone-like material and provided with tarsia decoration to be obtained in a very quick and continuously on industrial scale reproduceable way (thanks to the use of programmable DC machines). The invention has previously been described with reference to a particular form of embodiment, in which the final product is constituted by a flat tile having a supporting base and a monochromatic tarsia decoration. However, the invention is not limited to this form of embodiment, and it provides for several variants which fall within its scope. According to a first variant, the invention may be applied for the tarsia working of stone-like materials having any shape, e.g. blocks, tiles and others. In fact, once the material to be decorated has been provided with the notches for acco odating the decoration, it suffices to place on that material a slab in which the decorative pattern is machined in relief and to longitudinally cut the assembly. According to other forms of embodiment, the invention may easily be carried out in order to obtain multicoloured tarsia-worked products: in fact, the process according to the invention may be repeated on different slabs of various materials, thereby obtaining, for instance, a first supporting slab provided with a series of notches suitable for accomodating the relief patterns carried by a second, a third and a fourth slabs which are superimposed one after the other in order to form a stratified product, the visible surface of which is provided with a multicoloured decorative tarsia pattern. According to further forms of embodiment, which are obtainable by using DC machine tools, the invention is not limited to the production of elements which are tarsia-worked on a single plane: in fact, by using a DC machine having five working axles, any kind of tarsia decoration may be carried out, also on curved surfaces. These and other variants fall within the scopes of the invention, in the range of mechanical equivalences.

Claims: CLAIMS 1. Process for tarsia-working of stone-like materials as marble, stone, granite or the like, in which a first supporting element (12) accomodates on its visible surface at least a second element (11) forming a decorative tarsia pattern, characterised in that said first element is machined by means of a digitally controlled (DC) machine tool in order to form on it a series of grooves and/or notches (14), in that a suitable bonding agent is laid down on said grooves and/or notches, in that said at least a second elemnt is machined by means of a digitally controlled (DC) machine tool in order to form on it, in relief, a decorative pattern or portions of a decorative pattern, in that said at least a second element is embedded in said grooves and/or notches, and in that the supporting material belonging to said at least a second element is removed from the formed block, thereby enabling the sight of the decorative pattern formed on said first element . 2. Process according to claim 1, characterised in that said first element is configurated as a block, or a tile, or other . 3. Process according to anyone of the preceding claims, characterised in that said suitable bonding agent is constituted by a glue or by a resin. 4. Process according to anyone of the preceding claims, characterised in that said DC machine tool is provided with diamond or hard-metal cutters in order to form said notches and/or grooves and said decorative pattern in relief on said first and at least a second element. 5. Process according to anyone of the preceding claims, characterised in that the final product is smoothed and/or polished and/or sandblast. 6. Process according to anyone of the preceding claims, characterised in that a plurality of second elements (11) provided with areas in relief suitable to be accomodated in said grooves and/or notches are superimposed to said first element (12). 7. Process according to anyone of the preceding claims, characterised in that the surface on which the tarsia working is carried out is flat and/or curved. 8. Product constituted by a tarsia-worked stone-like material as marble, stone, granite or the like, in which a first element forming a support is provided with a tarsia decorative pattern constituted by at least a second material, characterised in that said product is obtained by means of a process according to anyone of the preceding claims.

Inventors: PICCOLI EMILIO, PICCOLI, EMILIO
Applicants: ALPIMARMO A PICCOLI DI PICCOLI, ALPIMARMO A. PICCOLI DI PICCOLI NEREO EC. S.N.C.
Application year: 1992
Main classification: B44C3
IPC codes: B28D1, B44B3, B44C1, B44C3, C04B41