DESCRIPTION

The present invention relates to the field of surface processing of plate-shaped elements. In particular, the present invention relates to an innovative equipment for surface processing plate-shaped elements. In detail, the present invention relates to an equipment for surface processing plate-shaped elements, especially for sanding plate-shaped elements like tiles, plates or the like.

PRIOR ART

Equipment are known and widely used for the "industrial" sanding of tiles made of different materials, such as ceramic, marble, cement or the like, as well as of plates made of stone, metal or other material, wherein "industrial sanding" means, in the present invention, the sanding performed to uniform the tiles surface quality at the end of the production cycle and therefore before laying.

The solutions that are more performing and more commonly used provide for the use of a plurality of sanding modules arranged in succession above a conveyor belt that supports the tiles or plates and moves them along a given direction. Each module comprises a head rotating around a rotation axis that is substantially vertical (perpendicular with respect, to the surface of the tiles or plates to be sanded that are arranged on the conveyor belt in substantially horizontal position) ; the rotating head is equipped with a plurality of fickerts or fickert heads, and the rotation of the head results in a sanding action exerted on the tile or plates by the abrasive surface of each fickert head, wherein each fickert head, during the rotation of the head, is made pivot as a pendulum around a pivot axis perpendicular to the rotation axis of the head. Each module and/or rotating head can be translated both vertically (perpendicularly to the tiles) , in order to adjust the pressure exerted by the ficJcert heads on the plates, and transversally with respect to the conveyor belt, the transverse movement of the module or head being called "traverse".

The fickert heads of the various rotating heads arranged in succession along the conveyor belt are characterized by abrasive surfaces of different abrasive degree; in detail the abrasive degree is greater for the first heads acting on the tiles and decreases more and more for the following heads, up to the last heads.

The equipment of this type are provided with a hydraulic system for cooling the abrasives and keeping the conveyor belt clean during the work. Moreover, the vertical movement of the rotating heads is provided by means of pneumatic cylinders .

The prior art equipment described above, even if appreciable from many viewpoints, have however some drawbacks and/or disadvantages.

A first disadvantage is the length of the traditional sanding lines, that are too long to achieve speeds allowing a satisfactory industrial productivity.

A further disadvantage is that a significant amount of water is required during machining in order to lubricate and cool the tools, equal to approximately 80/100 1/min. for each fickert head, which is very expensive. Moreover, the use of water requires significant investments for water purification systems that shall manage flow, deposit and separation of sludge.

It should be also rioted that the tools have an average life of two hours and it is necessary to stop the whole line to replace a single head. Moreover, the traverse width and speed shall be adjusted according to the width of the plates, and this processing requirement results in higher costs for producing the machine for larger formats as well as in mechanical limits that can be difficult to deal with.

Moreover, the whole process is based on the operative force of the fickert heads, that are very heavy {more than approximately 80 kg each) and numerous, and cause therefore a significant power consumption and a significant wear of the mechanical components thereof.

Lastly, in order to manage so complex and long equipment and lines, a high number of operators is required, as well as a high number of tools; not only the number of tools varies based on the quality of the single operator's work, but the use of a high number of tools result in a large amount of production waste when using these prior art equipment .

DESCRIPTION OF THE PRESENT INVENTION

An object of the present invention is to provide an equipment allowing to overcome or at least minimize the problems of the prior art equipment described above.

In particular, an object of the invention is to provide an equipment allowing the natural cooling of the abrasive, thus making the water lubrication unnecessary, with significant savings as regards both the necessary systems and the power consumption.

A further object of the invention is to ensure the processing of all the surfaces of all the predefined formats of tiles; in this way, there is no more need for the traverse bridge and you have no longer all the prior art inconveniences due machine stops, abrasive replacement and format change.

The equipment according to the invention also allows to limit the overall bulk, that is preferably equal to the half of the usual bulk of a prior art equipment, ensures production continuity also during abrasive replacement, and ensures the abrasive tools a life 4-times greater than that of the traditional tools.

A further object of the invention is to provide an equipment offering maximum guarantees as regards safety, in particular during maintenance operations, and/or the possibility of replacing the tools when the equipment is still working, with significant savings in terms of time and costs .

Moreover, the equipment according to the invention has limited weight (with respect to the weight of the prior art equipment) and can be therefore easily installed anywhere in a plant, without the need for brick works and the like.

In view of the drawbacks of the prior art devices described above, and of the objects of the invention listed above, the present invention therefore provides for an equipment for the surface sanding of plate-shaped elements, in particular of tiles, said equipment comprising support and feeding means for supporting said plate-shaped elements and feeding them along a given feed direction, so that, during the movement along said given direction, the surface of each plate-shaped element to be sanded can be visible and accessed, the equipment including a sanding module provided with sanding means that define a sanding abrasive surface and with moving means that move said abrasive surface into contact with the visible surface of the plate- shaped elements in succession during the forward movement thereof; the sanding means comprise a closed belt that defines the sanding abrasive surface and is suitable to be driven into rotation by means of the moving means. According to an embodiment, the closed belt extends along a direction other than the feed direction of the plate- shaped elements.

According to an embodiment, the closed belt can be oriented, with respect to the feed direction of the plate- shaped elements, at will between two end positions where it extends along two different directions, respectively a transverse direction and an oblique direction with respect to the feed direction of the plate-shaped elements.

According to an embodiment, the closed belt extends between two opposite pulleys, whose rotation axes are parallel to each other and orientable with respect to the feed direction of the plate-shaped elements.

According to an embodiment, a first pulley of the two pulleys is driven into rotation by means of the moving means, while the second pulley of the two pulleys is driven into rotation by means of the closed belt.

According to an embodiments, the moving means comprise a power source and transmission means interposed between the power source and the first pulley.

According to an embodiment, the transmission means comprise a third pulley rigidly fixed to the first pulley through a drive shaft and a drive belt interposed between the power source and the third pulley.

According to an embodiment, adjusting means are provided for regulating the tension of the closed belt.

According to an embodiment, the adjusting means are so shaped as to allow the regulation of the centre-to-centre distance between the first pulley and the second pulley. According to an embodiment, adjusting means are also provided for regulating the contact pressure of the sanding abrasive surface against the visible and accessible surface of the plate-shaped elements. According to an embodiment, said adjusting means comprise at least one pressing element suitable to exert an adjustable pressure against the inner surface of the closed belt opposite to the sanding abrasive surface.

According to an embodiment, the equipment comprises a plurality of modules arranged in succession along the feed direction of the plate-shaped elements.

Any further embodiments of the equipment according to the invention are defined in the claims.

BRIE1T DESCRIPTION OF DRAWINGS

The invention will be better explained in the following description of the embodiments illustrated in the drawing. However, it should be specified that the present invention is not limited to the embodiments described below and illustrated in the drawing; contrariwise, all variants and modifications of the embodiments described and illustrated in this document that are clearly apparent to those skilled in the art fall within the scope of the invention.

Moreover, as the invention can be advantageously applied in particular to the sanding of tiles, in the description below reference will be made to the possible applications and the use methods for sanding tiles, being however understood that the possible advantageous applications of the invention are not limited to the field of tiles, but comprise the surface processing of any plate-shaped element..

In the drawing:

Fig. 1 is a plan view from the top of an equipment according to an embodiment of the invention;

Fig. 2 is a plan view from the top of a sanding module of an equipment according to an embodiment of the invention from a point of view opposite to that of Fig. 1;

Fig. 3 is a schematic side view of a sanding module of an equipment according to an embodiment of the invention; Fig. 4 is a schematic side view of a sanding module of an equipment according to an embodiment of the invention; Fig. 5 is a perspective view of a detail of Fig. 3, in enlarged scale and with some parts removed for the sake of clarity.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

In Fig. 1, the reference numbers 100 and 200 respectively indicate a conveyor belt and a sanding module of an equipment 300 according to a first embodiment of the invention.

Through the conveyor belt 100, known and therefore not described in detail for the sake of conciseness, plate- shaped bodies 101, like tiles or the like, are supported and moved, in particular moved forwards at a predefined speed that can be adjusted according to the needs and/or circumstances, in particular according to the desired sanding degree, along a feed direction D indicated by the arrow in Fig. 1, wherein the bodies 101, during their forward movement along the direction D, are arranged on the conveyor belt 100 so that the surface to be processed (to be treated, in particular to be sanded) can be visible and accessed.

Along the conveyor belt 100, in particular above it, a sanding module 200 is arranged, suitable to sand the visible surface of each plate-shaped body 101 according to the methods explained in more detail below. It should be specified that the sanding module 200 comprises a rotating sanding belt 201, extending along a direction X transversal and oblique with respect to the feed direction D of the bodies 101; the belt 201 has externally a sanding abrasive surface 214', that will be better described below, and it is therefore clearly apparent that each body 101 moving forward in the indicated direction through the conveyor belt 100 has a visible surface 1010 facing the belt 201, so that each surface 1010 is touched by the abrasive surface 214' of the rotating belt 201, wherein, according to the invention, also the rotation speed of the belt 201 can be adjusted according to the needs and/or circumstances. With particular reference to Fig. 3, the belt 201 has a substantially horizontal operative branch 2010 arranged at the bottom between the pulleys 204 and 205, and a substantially horizontal idle branch 2011 facing at the top the branch 2010.

Moreover, the module 200 can be oriented with respect to the conveyor belt 100, in particular so as to allow the orientation of the sanding belt 201 between two end portions where the belt extends (according to the plan view from the top of Fig. 1) along the transverse and oblique direction X (Fig. 1} and respectively along a direction substantially perpendicular to the feed direction of the bodies 101.

The length of the belt 201, in particular the extension thereof in the plane (see the description below) , is greater than the width of the conveyor belt 100, thus allowing the surface processing (sanding) of plate-shaped elements 101 of any length and whose width is substantially equal to, or slightly greater than, the width of the conveyor belt 100.

Here below, with reference to Figs. 2 to 4, further characteristics and/or features of the equipment 300 according to the invention will be described and explained, in particular characteristics and features of the sanding module 200, wherein in Figs. 2 to 4, components and/or features of the sanding module 200 already described with reference to other figures are identified by the same reference numbers, and wherein, in Figs. 2 to 4,, the conveyor belt .100 is not shown for the sake of clarity. Fig. 3 shows a side view of the module 200 from a point of view arranged upstream of the module 200 with respect to the feed direction of the bodies 101 (at the top with reference to Fig. 1); Fig. 4 shows a side view of the module 200 from a point of view arranged downstream of the module 200 with respect to the feed direction of the bodies 101 (at the bottom with reference to Fig. 1} .

As shown in the figures, the module 200 comprises a support main frame 210 and support means 211, through which the frame 210 (and therefore the whole module 200) may be positioned (in particular hung) above the conveyor belt 100. A first rotation axle 208 and a second rotation axle or shaft 209 extend through the frame 210, means for facilitating the rotation of the axles 208 and 209 (such as bearings or the like, not shown in the figures) being interposed, if necessary, between each axle 208 and 209 and the respective housing seat provided in the frame 210. A pulley 204 and a pulley 205 are respectively engaged on the end portions of the axles 208 and 209 projecting from the frame 210 on a first side of the frame 210 (at the top with reference to Fig. 2) . The belt 201 (Fig. 3) extends between the pulleys 204 and 205 so as to form a closed belt, in particular so as to define two flat, parallel and opposite portions, joined by means of two curved portions respectively engaging the two pulleys 204 and 205. In particular, the belt 201 comprises a flexible main portion (layer) 213, on which a plurality of fickert heads 214 are applied, defining an annular sanding abrasive surface 214' .

As mentioned above, the module 200 is arranged on the conveyor belt 100 so that the visible surface 1010 of the bodies 101 is touched by the substantially linear portion of the belt 201 adjacent to the conveyor belt 100 and therefore by the abrasive heads 214 carried by the same belt 20.1. Each abrasive test 214 is applied to the belt 201 through the interposition of a base 2140 carrying abrasive bodies 2142. Each base 2140 is made of a material that is elastically deformable under pressure, in order to allow the respective abrasive bodies 2142 to move transversally to the direction X and to the direction D in order to optimize the interaction with the plate-shaped bodies 101 moving forwards.

A third pulley 206 is engaged on the end portion of the axle 209 projecting from the frame 210 on the second side of the frame 210 {opposite to the first side and therefore at the bottom with reference to Fig. 2) ; the module 200 also comprises a power source 202, for example, although without limitation, an electric motor, with a rotation shaft on which a pinion 207 is engaged, arranged, with respect to the main frame 210, on the same side as the third pulley 206. A drive belt 203 extends between the pulley 206 and the pinion 207, and it is therefore clearly apparent that the starting of the motor 202 (for example supplying electricity, in the case of an electric motor) results in the rotation of the pinion 207, and therefore in the rotation of the third pulley 206 through the drive belt 203, as well as in the rotation of the pulley 205 (as the pulleys 206 and 205 are engaged on opposite ends of the same axle or shaft 209) , and in the rotation of the belt 201 and of the pulley 204, drawn by the belt 201. It should be specified that the module 200 also comprises adjusting members 212 interposed between the axles 208 and 209, these adjusting members 2.12 being especially suitable to regulate the center-to-center distance of the axles 208 and 209, and therefore the tension of the belt 201. In the specific case illustrated in Fig. 4, the adjusting members 212 are suitable to regulate the position of the axle 208; the adjusting members are known in se and therefore they will not described in greater detail below for the sake of conciseness, wherein equivalent adjusting means {not shown) can be also provided in the present invention in order to regulate the tension of the drive belt 203.

Fig. 3 shows an appreciable (optional) feature of the sanding module according to the present invention. In particular, in Fig. 3, between the pulleys 204 and 205 and in the inner space defined by the belt 201 between the branches 2010 and 2012, the frame 210 carries a bracket 211 and this bracket carries, in turn, an adjusting unit 215 suitable to regulate precisely the contact pressure of the branch 2010 of the belt 201 on the bodies 101 that are supported and moved by the conveyor belt 100. The adjusting unit 215 comprises a plurality of pressing elements 216 arranged in succession between the pulleys 204 and 205 along a predefined portion of the linear segment of the belt 201 and carried movable transversally to the direction X and to the branches 2010 and 2012 of the belt 201. In particular, each pressing element 216 is substantially parallelepiped-shaped ana the bracket 211 carries a guiding member for guiding the rectilinear movement, of each pressing member 216, the guiding member being constituted by a rod 2.111 engaging the corresponding pressing element 216 transversally. For the sake of practicality, in Fig. 5 only one rod 2111 has been shown, in correspondence of a first actuator 217 arranged at the side of the pulley 205. Moreover, the bracket 211 carries a linear actuator 217 for each pressing element 216, wherein the stem 2170 of each actuator 217 is parallel to the respective rod 2111. Moreover, with reference to Fig. 5 again, each pressing element 216 carries, at the bottom, a roller 2160 that is oriented transversally to the direction X and is provided with a plurality of round nips 2162 arranged longitudinally stepped. With reference to Fig. 5 again, the belt 201 has an inner face 2014 provided with a plurality of reliefs 2015, configured to engage the nips 2162 in a conjugated manner in order to define a guiding device 2016 for guiding the branch 2010 of the belt 201. It is easily understood that the pressure exerted, in use, by the pressing elements 216 on the belt 201, and therefore the pressure the abrasive surface 214' /the belt 201 exerts on the bodies 101, depends on the pressure exchanged between the reliefs 20.15 and the nips 2162, and therefore on the pressure exerted by the actuators 217 on the pressing elements 216.

In particular, although without limiting the scope of the invention, in case the actuators 217 are of the pneumatic type, a compressor 2172 can be provided (shown only in Figs. 2 and 4 for the sake of drawing economy), that can be powered through the same power source 202 and is configured to actuate each actuator 217 singularly. The module 200 also comprises a control, device 2174 {Fig. 2) carried by the frame 210 and connected to the compressor 2172 to control the actuators 217 singularly. In view of the above description it is clearly apparent that, in use, the pressure exerted by each actuator 217 can be adjusted individually, increasing or decreasing, in real time, the pressure distribution on the plate-shaped bodies 101 moving along the drawing direction of the belt 201, associating sensors 102 with the conveyor belt 100, the sensors being electronically coupled to the control device 2174 (the electronic connection between the mentioned components is not shown for the sake of drawing economy) , wherein the sensors 102 are able, in use, to detect in real time the point-to-point surface conformation of the bodies 101 fed to the module 200 through the conveyor belt 100.

As it is clearly apparent and proved from the description above of the embodiments shown in the figures, the present invention allows to achieve the above mentioned objects and purposes. In particular, the equipment according to the invention has reduced bulk, in particular the sanding module is actually compact and not bulky, allows to avoid the use of cooling water (as the belt is cooled in a natural way) and therefore the need for disposal and/or purification systems, avoids the need for traverse (wherein the belt extends along at least the whole length of the conveyor belt), thus allowing to limit the production costs; moreover, the sanding module is suitable to be installed on existing conveyor belts without significant modifications thereof, allows a significant reduction of power: consumption and the mechanical components thereof have limited wear.

Lastly, the equipment management is simple, and requires a reduced number of operators; the same applies to maintenance, both ordinary and extraordinary, allowing at the same time a significant reduction in process waste.

It should be specified that the description above and the attached figures relate only to an embodiment of the invention; it should be however specified that the description above does not limit the possible embodiments of the invention falling within the scope thereof.

For example, as mentioned, both the feeding speed of the bodies 101 and the speed of the belt 201 can be adjusted at will. Moreover, as regards the methods of use of the equipment, the stop of the conveyor belt 100 can be provided when the body 101 to be sanded is arranged in correspondence of the module 200.

It should be also specified that the sanding module 200, together with the sensors 102, can be used in a sanding line to adjust the regulation thereof, for example by detecting defects of the plate-shaped bodies 101 fed along the direction D for post-processing activities, useful to asses the actual surface finishing of the plate-shaped bodies 101, as well as to give the plate-shaped bodies 101 surfaces 1010 that comply with the project specifications. Moreover, according to the present invention, more modules 200 can be provided in succession along the conveyor belt 100, the number thereof can vary according to the needs and/or circumstances, and they can be directed differently with respect to the feed direction of the plate-shaped bodies 101.

The scope of the present invention is defined by the appended claims.