Technical Field

The present invention relates to a plant for processing ceramic products, natural stones, or the like, comprising at least one head for processing the products, e.g., grinding, polishing, etc.

Background Art

With particular reference to the ceramic industry sector for the processing of surfaces of ceramic products such as tiles or slabs, or natural stones, or the like, it is known to carry out processing operations such as smoothing, lapping or polishing, in order to improve the surface finish.

These processing operations, e.g. smoothing, are generally carried out by means of processing plants that involve the use of specific processing heads that can be operated in rotation around a relevant axis and supporting a plurality of tools suitable for the aforementioned surface processing of ceramic products, natural stones or the like.

In order to operate effectively, the processing heads need removal means for removing the material removed during processing. In many known solutions these tasks are entrusted to a fluid, in almost all cases the fluid is water.

In such cases, the material removed during processing takes the form of sludge. There is then a first drawback related to the need to dispose of the relevant sludge, resulting in bureaucratic burdens and management costs.

Other solutions, on the contrary, use air as a means of powder extraction.

The international application published under the number WO2017168366A1, under the name of the same Applicant, describes a machine that uses air instead of water as a means of tool cooling and also as a means of extracting the powder removed from the manufactured products.

This international application describes a machine provided with a plurality of heads, as well as with first cooling and extraction means arranged around each processing head, with second cooling and extraction means arranged around the perimeter of the processing area of the ceramic manufactured products and third cooling means arranged in the center and/or inside each head.

Even with the use of such cooling and extraction means it is not always possible to prevent the powder produced from accumulating underneath the processing tools, making them ineffective.

This circumstance represents a very detrimental problem for the quality of the processing because the presence of powder on the surface of the manufactured products can cause scratches and irregularities in the finish.

Another drawback is the dispersion of powder and processing debris within the working environment and this can be very dangerous and harmful to the operators’ health.

Description of the Invention

The main aim of the present invention is to improve the state of the art in the field of processing plants for ceramic products or natural stones.

As part of this aim, one object of the present invention is to provide a processing plant, comprising processing heads, that allows the heads to work under optimum conditions, almost completely eliminating the presence of powder.

Another object of the present invention is to provide a processing plant with extraction means that effectively draw powder and processing debris between the tool and the surfaces of the manufactured products.

A further object of the present invention is to confine the processing area so that the powder coming from the surfaces of the ceramic manufactured products or natural stones being worked and from the wear of tools are not dispersed in the surrounding environment.

These and other objects of the present invention are achieved by a processing plant according to claim 1.

Dependent claims refer to preferred and advantageous embodiments of the invention.

Brief Description of the Drawings Further characteristics and advantages of the present invention will be more evident from the detailed description of a non-exclusive embodiment, of a processing plant comprising processing heads according to the present invention, given by way of example but not limited to, in the attached tables of drawings in which:

Figure 1 is a perspective view of a plant for processing ceramic products or natural stones comprising processing heads provided with extractor hoods according to the present invention;

Figure 2 is a perspective view of some processing heads provided with the extractor hoods in Figure 1;

Figure 3 is a perspective view of the outside of the extractor hood of the processing plant referred to in the preceding figures;

Figure 4 is a perspective view of the inside of the extractor hood of the processing plant referred to in the preceding figures;

Figure 5 is a top view of the extractor hood of the processing plant referred to in the preceding figures;

Figure 6 is an enlarged view of a detail of the lateral wall of the extractor hood of the processing plant referred to in the preceding figures; and Figure 7 is an enlarged view of another detail of the extractor hood referred to in the preceding figures.

Fmbodiments of the Invention

With reference to the attached figures, reference numeral 1 globally indicates a plant for processing ceramic products, natural stones, or the like.

The following description will only relate to ceramic products, however, it should be understood that the present invention can also be used for natural stones, or the like.

The plant 1 comprises a supporting frame 2 with which a holding surface 8 is associated on which there are ceramic products 9 provided with an upper surface 11 to be processed.

The holding surface also serves as a means of transport for the forward movement of the aforementioned ceramic products 9, along a direction of forward movement identified with arrow A, e.g. the holding surface may comprise a conveyor belt 8.

The plant 1 comprises at least one processing head 5 and in particular a plurality of processing heads 5, the processing operations performed by the heads 5 can be any type of processing operating on the surface 11 of the products 9 and that generates powder and debris, smoothing being an example of the processing operation.

The heads 5 are arranged in succession to each other along the direction of forward movement A and above the conveyor belt 8.

The heads 5 are operated by motor means 12 and are supported by swinging beams 6 that swing in a transverse direction 7.

Each processing head 5 has an axis 20 that can be considered a geometric axis of the whole head 5. Depending on the type of processing operation, the head 5 can also rotate around the axis 20.

Each processing head 5 is provided with at least one tool 10 at the lower end in contact with the surface 11, and, in some cases, with a plurality of tools 10 for processing the ceramic products 9; the tools 10 define a processing area for the surface 11 of the ceramic products 9.

The processing heads 5 and the relevant tools 10 of the plant 1 are not described in more detail because they are not part of the present invention; as mentioned above, it must be kept in mind that the aforementioned processing heads 5 and the relevant tools 10 can be of any type to carry out a processing operation and to define a processing area on the ceramic products.

According to the present invention, the plant 1 comprises extraction means 30, indicated in Figures 3-4-5, which extract the powder and debris generated by the processing of the products 9.

In turn, the extraction means 30 comprise containment means of the processing heads 5 and of the processing area on the surface 11 of the products 9.

The extraction means 30 are substantially shaped like a hood 3 or a bell comprising, in turn, a lateral wall 31. According to a version of the present invention, each hood 3 is fastened to its respective processing head 5 and lowers and raises with it; when the vertical position of the head 5 is adjusted, the hood 3 moves accordingly, swinging together with the respective head 5. According to another version of the present invention, each hood 3 is independently fastened to the same beam 6 that supports the head 5; during the processing operation each hood 3 swings with the beam 6 itself, it is not subject to the vertical adjustment of the respective head 5 and the adjustment of the vertical position of the hood 3 is made independently of the vertical adjustment of the respective head 5.

As a non-exhaustive example, the lateral wall 31 of each hood 3 may have a thickness varying between three and six millimeters, and is arranged substantially perpendicular to the surface 11 of the underlying ceramic product 9 being processed. According to a version of the present invention, the lateral wall 31 of each hood 3 has a continuous extension without edges: geometrically, each point of the perimeter of the lateral wall 31 has a unique tangent and is without points of singularity.

The lateral wall 31 of each hood 3 has a convex perimeter in the plan view and a substantially circular, or oval, or elliptical, or polygonal shape with rounded edges.

These measures, concerning the lateral surface and the pattern of the perimeter of the lateral wall 31 of the hood 3, are essential to avoid the formation of areas where powder can slow down or accumulate without control and to avoid there may be positions, e.g. edges, where the lateral surface can bend and powder can escape outside the hood 3.

In addition, thanks to these measures, the lateral wall 31 is substantially tensile- stressed, allowing for safe and unhindered powder containment.

The hoods 3 can be made of any material, they can be made e.g. of metal sheet or thermoformed in ABS (acrylonitrile-butadiene- styrene). According to a version of the present invention shown in Figure 5, each hood 3 is in an eccentric position with respect to the axis 20 of each head 5. More specifically, each hood 3 has its own geometric center spaced by a predetermined distance “D” from the center of the respective processing head 5, this center being defined substantially by the axis 20 of the processing head 5. This way, an area 21 with a larger passage section (Figure 5) is created inside the hood 3, due to the greater distance of the lateral wall 31 of the hood 3 from the lateral surface of the processing head 5 and the corresponding tools 10. Therefore powder and debris formed during processing operations, which are substantially carried away by the speed of the airflow due to the movement of the processing head 5, have a slowdown in the larger section area 21. According to one version of the present invention, an extraction manifold 32 is located in the proximity of the area 21 to extract powder and processing debris. The extraction manifold 32 comprises a substantially cylindrical duct, arranged substantially vertically, which allows easily sucking up powder and processing debris that slow down in the larger section area 21. In a version of the present invention, the extraction manifold 32 comprises a substantially cylindrical duct with an inlet port 33; this inlet port 33 may be substantially circular or slotted (not shown).

The inlet port 33 of the manifold 32, inside the hood 3, as can be seen in Figure

4, is made in such a way as to facilitate the inlet of powder; the extraction surface of this port 33 is not facing downwards, but is arranged obliquely forming a certain angle B with the upper horizontal surface of the hood 3.

Clean air, or other gaseous means, is blown axially in the center of the head 5 through one or more substantially cylindrical ducts; the air in contact with the upper surface of the ceramic product 9 takes on a radial direction that follows the centrifugal force generated by the rotary movement of the head 5 and thus passes through the plurality of tools 10, pushing the powder generated by the processing operation towards the walls 31 of the hood 3 that surround the head

5.

The lower and end part of the hood 3, comprises a band 34, or belt, substantially ring-shaped made of a flexible material and resistant to abrasion and wear, for example it might be a polymeric material such as polyurethane or rubber. Figure 6 shows that the edge of the lower part of the band 34 is made with rounded edges and that it is positioned at a certain height “H” from the surface 11 of the ceramic product 9 being processed; the height of the band 34 from the surface of the ceramic product 9 must be the minimum possible in order to reduce losses during extraction and the dispersion of powder and debris in the environment.

It is therefore necessary to optimize the height “H” of the edge of the lower part of the band 34 in order to avoid any contact with the ceramic product 9 being processed and, at the same time, to avoid losses during extraction and dispersion of powder and debris in the environment; as a non-limiting example, the height “H” is comprised between 5 and 15 millimeters.

The band 34, in the same way as a belt, overlaps itself at the junction 35 and is fastened to the upper part 36 of the hood 3 by means of special fastening means 37 of the solvable type. The hood 3, thus obtained, confines the work environment of the processing head 5 by creating a closed compartment, where the clean air blown in and the air contaminated by the processing powder is extracted by the extraction manifold 32, generating a continuous extraction flow of the powder itself.

The plurality of tools 10, in order to be able to process the ceramic products 9 in the best possible way, must be in contact with their surface 11; however, after numerous processing cycles, the tools 10 tend to wear and tear.

For this reason, the head 5 has therefore to lower accordingly to compensate for the wear of the tools 10 so that they can continue to work in contact with the surface 11; for example, the lowering can vary from ten to fifteen millimeters. In a version of the present invention, when the head 5 lowers, the hood 3 that is connected to the head 5 also lowers, the band 34 consequently approaches the surface 11 and eventually can also come into contact with said surface 11 without opening or detaching, maintaining the seal on the external edge of the hood and decreasing the passage on the edge of the hood 3. In another version of the present invention, the ring-shaped band 34 is connected to the upper part 36 of the hood 3 by means of the sliding connection means 40 (Figure 7) that allow the band 34 to move vertically with respect to the upper part 36.

When the head 5 lowers to compensate for tool wear, the upper part 36 of the hood 3, which is connected to the head 5, lowers with it, however, unlike the previous version, the ring-shaped band 34, which can move vertically with respect to the upper part 36, remains at a fixed vertical height with respect to the surface 11 of the product 9 being processed, keeping the small passage on the edge of the hood 3 constant.

In a version of the present invention, the hood 3, with the relevant upper part 36 and the ring-shaped band 34, is fastened to the beam 6 swinging independently of the processing heads 5.

When the head 5 is adjusted to compensate for the wear of the tools 10, e.g. by a lowering movement, the hood 3 and the corresponding band 34 are not affected by the adjustment of the head 5, in this case the adjustment of the band 34 is independent of that of the head 5.

According to a version of the present invention, the hood 3 comprises a door 38 that closes an inspection opening 41 to check the working conditions of the tools 10, the quality of processing operations on the ceramic products 9 and to replace the worn tools 10; after having disassembled the band 34 of the hood 3, the door 38 can be moved vertically by loosening a blocking screw operated by a knob 39 and releasing the inspection opening 41. In another embodiment of the present invention, in order to inspect the head 5, the band 34 is fastened in a sliding manner onto the upper part 36 of the hood 3 by means of sliding connection means (not shown). If necessary, the above mentioned sliding connection means may be the same means 40 that allow the band 34 to move vertically with respect to the upper part 36 during the processing operation and as a result of the wear of the tools 10.

In a further embodiment of the present invention, in order to be able to inspect the head 5, the tools 10 and the ceramic products 9, the hood 3 is fastened to the head 5 by means of the second sliding connection means (not shown). This way, the entire hood 3, including the band 34, can be lifted up so that the head 5, the tools 10 and the ceramic products 9 can be exposed. The presence of the hood 3 with the band 34 adjacent to the ceramic products 9 and completely surrounding the tools 10 during the processing operation, allows the powder in the work environment to be almost completely eliminated.

The effectiveness of the tools 10 is also greatly improved thanks to the very efficient extraction of the powder from the work area. This is due to the special design of the hood which is eccentric and has a larger extraction flow passage section which helps to capture powder particles and also to the inclination of the inlet port 33 of the manifold 32.

The invention thus conceived is susceptible to numerous modifications and variants all falling within the scope of the inventive concept.

In addition, all details can be replaced with other technically equivalent elements. In practice, the materials used, as well as the contingent shapes and sizes, can be any according to the requirements without leaving the scope of protection of the following claims.