Method for forming floor tiles

Abstract

 The present invention relates to a new method for forming a series of separate floor tiles (1). The method comprises the following steps:
- pouring concrete (2) to form a concrete layer (3) of a well-defined layer thickness;
- levelling the poured concrete layer (3);
- subjecting the top side of the concrete layer (3) to a first polishing treatment;
- filling a mixture of quartz and cement into a concrete layer (3) and then mixing the infill mixture with the concrete layer (3), thus forming a top layer (4);
- subjecting the formed top layer (4) to a second polishing treatment;
- cutting the concrete layer (3) into separate floor tiles (1) to the desired tile format.

Description

[0001] The present invention relates on the one hand to a method for forming tile elements. On the other hand, the present invention relates to a device for forming separate floor tiles. The present invention relates in particular to a method for forming a series of separate floor tiles.

[0002] At present, many different types of floors are already known, such as for example parquet, floor tiles, carpet, concrete floor, poured floor, etc. Thus, US 5,441,677 and German patent publication DE 199 05 770 describe a method for forming a concrete floor in which expansion joints are provided in the poured concrete which allow the poured concrete floor to harden. However, the present invention does not relate to forming such concrete floors but to a method for forming a series of separate floor tiles which can be used to form a floor covering.

[0003] Floor tiles are a popular form of floor covering. In terms of floor tiles, there are three kinds of tiles, i.e. natural stone tiles, ceramic tiles and cement or concrete tiles. They each have their own character with specific advantages and disadvantages.

[0004] Natural stone tiles have a unique and lively appearance. They are formed from large blocks which are quarried in quarries and subsequently sawn to form plates or tiles.

[0005] Ceramic tiles are relatively thin slices of ceramic material in various forms, dimensions and thicknesses. They are hard, strong, hygienic, easy to clean and are used for covering both floors and walls.

[0006] Ceramic floor tiles are made from a mixture of clay and sand, if desired combined with several different natural substances, each of which may have their own effect. In the process of producing such floor tiles, the mixtures are ground to the required size, dried to a specific degree of moisture, formed into the desired shape and then fired at a temperature of 1000 to 1250 degrees, depending on the desired type of tile. Ceramic floor tiles are formed by drawing or pressing. Pressed tiles are manufactured by moistening a pulverulent mixture and pressing this mixture into a mould under high pressure. Drawn tiles are formed by drawing the clay mixture in paste form through special injection nozzles.

[0007] In contrast to natural stone or ceramic tiles, concrete or cement tiles are mainly suitable for outdoor use. Such tiles are produced by pouring concrete or cement into pre-formed moulds and then allowing these to harden.

[0008] It is an object of the present invention to provide an alternative method for forming a series of separate floor tiles which, inter alia, allows floor tiles to be produced in a simple, uniform and practical manner.

[0009] The object of the invention is achieved by providing a method for forming a series of separate floor tiles comprising the following steps:

• pouring concrete to form a concrete layer of a well-defined layer thickness;
• levelling the poured concrete layer;
• subjecting the top side of the concrete layer to a first polishing treatment;
• filling a mixture of quartz and cement into the concrete layer and then mixing the infill mixture with the concrete layer, thus forming a top layer;
• subjecting the formed top layer to a second polishing treatment;
• cutting the concrete layer into separate floor tiles of the desired tile format.

[0010] Compared to the known methods of producing floor tiles, the above-described method according to the present invention has the advantage that the method can be controlled much more, resulting in end products of a higher quality. Using the method, it is moreover possible to produce perfectly flat floor tiles which can be used to make a floor without scratches and the like. In addition, the method does not depend on weather conditions. Preferably, the resultant separate floor tiles are taken away and stacked.

[0011] The first polishing treatment is carried out using a polishing device provided with solid plates which carry out a rotary movement, while the second polishing treatment is carried out using a polishing device provided with blades (fine blades) which also carry out a rotary movement. The first polishing treatment should be regarded as the rough treatment, while the second polishing treatment should be regarded as the fine treatment.

[0012] According to a preferred method, the formed top layer is subjected to a third polishing treatment, following the second polishing treatment. During the third polishing treatment, the "fine" blades of the polishing device which are used to carry out the polishing treatment are provided with protective elements which prevent them from damaging the top surface of the concrete layer. This third polishing treatment is carried out until the top surface of the concrete layer is smooth and shiny so that this top surface is given a mirror effect.

[0013] In a more preferred method according to the invention, the poured concrete layer is compacted, after levelling, by means of vibrating beams. Compacting of the concrete layer is carried out in order to remove air bubbles from the mixture. For compacting, use is preferably made of special high-frequency vibrating beams.

[0014] In a most preferred method according to the invention, the separate floor tiles are formed on a shuttering table. The shuttering table is in particular provided with a shuttering edge so that the poured concrete layer does not run off the table.

[0015] Preferably, said concrete layer comprises a reinforcement, preferably a reinforcement mesh. This may be provided, for example, by placing a reinforcement mesh on said shuttering table and pouring the concrete onto this reinforcement mesh. The reinforcement produces a stronger floor tile, as a result of which it can be more readily handled without the risk of breaking. In addition, the reinforcement prevents cracks and splits in the floor tile formed.

[0016] According to a particular method according to the present invention, the layer thickness of the concrete layer is between 2 and 12 cm. The layer thickness of the concrete layer is preferably between 2 and 8 cm, more particularly between 2 and 4 cm, and most particularly 3 cm.

[0017] According to a more particular method according to the invention, the surface area of the concrete layer is between 150 and 450 m². The surface area of the concrete layer is preferably between 150 and 350 m² and more particularly between 150 and 300 m².

[0018] With a preferred method according to the present invention, said mixture comprises colour pigments. In this way, it is possible to give the floor tiles a coloured appearance.

[0019] Another subject of the present invention relates to a device for forming a series of separate floor tiles, the device comprising:

• a shuttering table;
• means for supplying poured concrete to the shuttering table so that a concrete layer is formed on the shuttering table;
• cutting device for cutting the formed concrete layer into separate floor tiles;
• removal device for removing the floor tiles.

[0020] In order to treat the formed concrete layer, the abovementioned device may furthermore be provided with means which are suitable for treating, preferably polishing, the concrete layer formed on the shuttering table, such as for example one or more polishing devices.

[0021] The device according to the present invention is in particular suitable for carrying out the above-described method.

[0022] In order to further explain the features of the present invention, and to indicate additional advantages and details, a more detailed description of the method and device according to the invention is now given. It will be clear that nothing in the following description can be interpreted as a limitation of the protection defined in the claims.

[0023] In this description, reference numerals are used to refer to the attached drawings in which:

• Fig. 1 shows a representation of concrete being poured to form a concrete layer and the levelling thereof;
• Fig. 2 shows a representation of the filling in of the concrete layer with, for example, a mixture of quartz and cement;
• Fig. 3 shows a representation of a polishing treatment;
• Fig. 4 shows a representation of the cutting of the concrete layer into the desired tile format resulting in separate floor tiles being formed;
• Fig. 5 shows a representation of the removal of the formed separate floor tiles.

[0024] According to the present invention and, as appears from the attached figures, tile elements (1), preferably floor tiles (1), are formed by subjecting a poured concrete layer (3) having a well-defined layer thickness, to certain machine and manual treatments, as a result of which the appearance of the surface will become very smooth, flat and shiny.

[0025] The chosen layer thickness of the concrete layer (3) determines the thickness of the floor tiles (1). Preferably, the thickness of the concrete layer is between 2 and 12 cm. For standard floor tiles (1), a concrete layer of 2 to 4 cm, preferably 3 cm will be poured. For more specific floor tiles (1), concrete layers having a larger (up to 12 cm) or smaller (1 cm) layer thickness will be poured.

[0026] In order to be able to form a considerable number of floor tiles (1) in a single operation - in which all the steps of the method described are carried out - the choice is made to pour the concrete layer (3) on a surface area of between 150 and 450 m². However, it is evident that surface areas which are greater or smaller than these values are also covered by the scope of protection of the present invention. Preferably, the different floor tiles (1) are formed on a shuttering table (5) which has standard dimensions of 10.5 x 30 m.

[0027] The concrete used has a fixed composition and is produced by mixing water with a binder (such as cement) and granulate (sand and gravel), fillers and, if desired, aggregates (e.g. silicon powder). The recipe which is used for the concrete depends on the desired strength and desired properties which the floor tiles (1) are to have.

[0028] In order to improve or modify the properties of the tile elements (1) to be formed, various additives can be used, such as for example:

• (super) plasticizers which increase the processability of the concrete without the addition of extra water;
• hardening accelerators;
• hardening retarders, as a result of which the concrete mixture can be processed for a relatively long time;
• bubble formers to increase the frost-resistance;
• colour pigments;
• foam formers in order to achieve a lower density and thus an improved insulating value.

[0029] Since concrete is a relatively brittle material and in order to prevent the formed floor tiles (1) from breaking immediately, the poured concrete layer (3) comprises a reinforcement. To this end, and as is illustrated in Fig. 1, the concrete, preferably from a concrete mixer (6), is poured onto the shuttering table (5) which is provided on its outer periphery with (e.g. steel) edge profiles which form the shuttering edge and on which the reinforcement (e.g. a steel mesh) is already provided.

[0030] In order to form even stronger floor tiles (1), steel fibre-reinforced concrete can be used which is made by adding approximately 0.3 to 1 volume percent steel fibres to the concrete mixture. The steel fibres ensure that the concrete can absorb tensile forces and can withstand heavy loads so that the formation of cracks is limited.

[0031] After the concrete layer (3) has been poured, it is levelled. This can be carried out by moving a screed (7) across the concrete layer (3). Such a screed (7) can be arranged so as to be displaceable in a profiled-section rail which extends along the length of the shuttering table (5). When concrete layers of greater thickness are poured, from 6 cm, it may be necessary to subject the concrete layer which has already been spread and levelled to a compacting or vibrating operation. This may be carried out by means of special high-frequency vibrating beams.

[0032] The levelled and, if desired, compacted concrete layer (3) is then left to rest for a while until the poured concrete layer can be walked on, but is still sufficiently mouldable on its top surface (top side), this is also referred to as the semi-plastic phase. During this phase, water may be present on the concrete layer, which water first has to be removed before the next steps can be carried out.

[0033] Due to the abovementioned operations, a cement-rich mass is situated on the upper side of the concrete layer (3) and is subsequently subjected to various treatments in order to give the individual floor tiles (1) their smooth appearance. The upper side of the concrete layer (3), in particular the cement-rich mass, is first subjected several times to a first polishing treatment (rotary movement) (see Fig. 3). Preferably, the upper side of the concrete layer is treated using a polishing device(s) with a solid plate (such a plate has a thickness of approximately 5 mm and a diameter of approximately 90 cm. In the specialist field, this operation is referred to as "power-troweling". As a result of power-troweling, a "squashy mass" is obtained which is evenly spread and on which no water is present anymore.

[0034] As is illustrated in Fig. 2, the next step is then to fill in the concrete layer (3) with a mixture of quartz and cement and then to mix the infill mixture with the concrete layer (3), thus forming a top layer (4). In order to give the finished floor tiles (1) a colour effect, said mixture may furthermore comprise colour pigments.

[0035] Said mixture is dry and is preferably scattered across the concrete layer manually while it is still wet. The mixture is mixed with the concrete layer (3) by "rotating" the polishing device again until the top layer (4) has been mixed with the squashy layer which is present. In this way, a perfect bonding of the infill top layer (4) and the concrete layer (3) is achieved. The "rotation" is preferably carried out using a polishing device with flat plates and is known as "floating", during which the top side of the concrete layer (3) is made flatter and flatter by rotation, and the traces from earlier treatments are gradually erased. This process is repeated until the concrete layer is sufficiently hard and hardly any footprints or significant uneven structures remain visible.

[0036] After floating, a polishing device with fine blades (the fine blades have a thickness of 3 mm and are 15 cm wide and approximately 45 cm long and are attached to the arms of the polishing device by means of a bolt connection) is placed on the concrete layer and the latter is subjected to a second polishing treatment (see Fig. 3). By polishing the concrete layer (3) using fine blades, the pores are sealed as it were and an attractive even surface is obtained. The harder the concrete layer, the sharper the blade opening angle has to be. This method step has to be repeated continually (which may take hours) until the top surface of the concrete layer is completely shiny.

[0037] After fine rotation (second polishing treatment), the concrete layer is subjected to a third polishing treatment in which the fine blades of the polishing device are provided with protective elements, preferably made from plastic, e.g. nylon, in order to prevent damage due to the polishing action of the blades. This step is repeated until a perfect shiny surface is obtained. The object of the third polishing treatment is to perfect the top surface and to significantly reduce the risk of damage by fitting the protective elements. In addition, a more attractive and even colour can be obtained.

[0038] Once the concrete layer (3) has hardened sufficiently - in practice usually the next day - this concrete layer (3) is cut (see Fig. 4) to the desired tile format, for example by means of an automatic computer-controlled concrete saw (8). In practice, the following tile formats will be sawn: 15 x 15 cm, 20 x 20 cm, 25 x 25 cm, 30 x 30 cm, 40 x 40 cm, 50 x 50 cm, 60 x 60 cm, 70 x 70 cm, 80 x 80 cm, 90 x 90 cm, 1 x 1 m, etc. After the concrete layer (3) has been cut up, the separate floor tiles (1) are taken from the shuttering table (5) one by one by means of a removal device (9) and stacked on top of one another, as can be seen in Fig. 5.

[0039] With the device for forming floor tiles (1) according to the present invention, the concrete saw (8) is intended to run in the same rail as the one in which the above-described screed (7) is displaceably arranged. The device for forming floor tiles (1) will essentially comprise the following parts: a shuttering table (5), if desired provided with a shuttering edge, means for supplying poured concrete (2) so that a concrete layer (3) is formed on the shuttering table (5), a screed (7) and a cutting device (8) for cutting up the treated concrete layer (3). The screed and cutting device are displaceably arranged in a profiled-section rail which extends along the length of the shuttering table (5). After it has been poured, the concrete layer (3) is treated by means of polishing devices.

[0040] It is evident that the method described can also be used for forming other covering elements or outside wall cladding elements, such as for example: steps, table tops, kitchen worktops, bricks and the like.

[0041] The covering elements or outside wall cladding elements, in particular the floor tiles (1), formed according to the method of the present invention possess a hardness and durability which equal that of natural tiles. In addition, the formed floor tiles (1) or other covering elements also have the following advantages:

• resistant to wear;
• unique appearance;
• easy to maintain;
• quick installation;
• long lifespan;
• wide range of finishes;
• perfect finish.

Claims

1. Method for forming a series of separate floor tiles (1), characterized in that the method comprises the following steps:

- pouring concrete (2) to form a concrete layer (3) of a well-defined layer thickness;

- levelling the poured concrete layer (3);

- subjecting the top side of the concrete layer (3) to a first polishing treatment;

- filling a mixture of quartz and cement into the concrete layer (3) and then mixing the infill mixture with the concrete layer (3), thus forming a top layer (4);

- subjecting the formed top layer (4) to a second polishing treatment;

- cutting the concrete layer (3) into separate floor tiles (1) of the desired tile format.

2. Method for forming a series of separate floor tiles (1) according to Claim 1, characterized in that, after the concrete layer (3) has been cut up, the resulting separate floor tiles (1) are removed.

3. Method for forming a series of separate floor tiles (1) according to Claim 1 or 2, characterized in that the formed top layer (4) is subjected to a third polishing treatment, following the second polishing treatment.

4. Method for forming a series of separate floor tiles (1) according to one of the preceding claims, characterized in that, after levelling, the poured concrete layer (3) is compacted by means of vibrating beams.

5. Method for forming a series of separate floor tiles (1) according to one of the preceding claims, characterized in that the separate floor tiles (1) are formed on a shuttering table (5).

6. Method for forming a series of separate floor tiles (1) according to one of the preceding claims, characterized in that said concrete layer (3) is provided with a reinforcement.

7. Method for forming a series of separate floor tiles (1) according to one of the preceding claims, characterized in that the layer thickness of the concrete layer (3) is between 2 and 12 cm.

8. Method for forming a series of separate floor tiles (1) according to one of the preceding claims, characterized in that the surface area of the concrete layer (3) is between 150 and 450 m².

9. Method for forming a series of separate floor tiles (1) according to one of the preceding claims, characterized in that said mixture comprises colour pigments.

10. Device for forming a series of separate floor tiles (1), characterized in that the device comprises:

- a shuttering table (5);

- means for supplying poured concrete (2) to the shuttering table so that a concrete layer (3) is formed on the shuttering table (5);

- cutting device (8) for cutting the formed concrete layer (3) into separate floor tiles (1);

- removal device (9) for removing the floor tiles (1).

Drawing