DESCRIPTION

The present invention relates to a device for working objects, in particular, for cutting ceramic objects and their derivatives.

These objects, mainly used in construction, can be made of different materials which are distinguished both for the various physio-chemical characteristics and for the different mechanical properties thereof.

As a first approximation, ceramic materials of porous paste, such as bricks, terracotta and porcelain, and ceramic materials with compact paste, such as stoneware and porcelain can be distinguished.

The latter have a higher resistance than the first, and are thereby more difficult to process. In any case, cutting these materials with devices which provide for the use of specific cutting tools, usually disc-shaped elements, moved by an appropriate motor is well known.

The strong friction generated by the cutting tool against the article leads to an overheating of the tool itself thereby requiring temperature control by means of appropriate cooling systems.

A first type of cooling system, called wet cooling systems, includes the use of a liquid cooling agent, usually water.

The water is sprayed onto the tool and onto the working surface with the dual purpose of cooling the tool and cleaning the same of debris that can become caught in the cutting parts and then dab the tool and decrease the cutting efficiency.

A drawback of the wet cooling system is the production of waste sludge that forms with the combination of the sprayed water and the waste material.

This sludge is waste in all respects and must be disposed of according to the criteria established by current standards, including additional costs to the companies that carry out the above processes.

A second type of cooling system, called dry cooling systems, involves the use of a gaseous cooling agent, usually air. In dry cooling processes, the cooling takes place by means of air blowing directly onto the tool.

This includes the advantage of avoiding the production of waste sludge to be disposed of, directly allowing a partial or total recovery of the waste material.

A drawback of the dry cooling systems is related to the air-cooling capacity.

In the case of the processing of very durable material, such as porcelain stoneware, the tool reaches temperatures so high as to require reductions in the velocity of rotation of the tool, with a consequential increase in processing times and decrease in productivity.

For dry cooling systems, additionally, the need to increase the efficiency of the cleaning of the tool due to the jet of air which is blown onto the tool itself, is well known.

EP0897778A1 demonstrates a solution according to the state of technology.

The main task of the present invention is to provide a device which makes it possible the use of dry cooling systems for high-resistance materials, such as porcelain stoneware, without resorting to decreases in the velocity of rotation of the tools.

Within this aim, a purpose of the present invention is to simplify, with respect to known devices, the cooling and cleaning of the tool.

Another purpose of the present invention is to provide a device which allows the user to save costs, in terms of the management and disposal of waste resulting from the manufacturing process.

Another purpose of the present invention is to provide a device which overcomes the aforementioned drawbacks of the known technique within the framework of a simple, rational solution, simple and effective to use and with contained cost.

The above mentioned purposes are achieved by the present device for the processing of ceramic articles and the like having the characteristics of claim 1.

Other characteristics and advantages of the present invention are more apparent from the description of a preferred, but not exclusive, embodiment of a device for working ceramic objects and the like, illustrated by way of an indicative, but not limitative example in the accompanying drawing table in which figure 1 is a schematic view of the device according to the invention.

With particular reference to this figure, a device for working ceramic objects and the like is globally indicated with 1.

The device 1 is suitable to be installed on machines for cutting ceramic objects, such as, for example, machines to be inserted in production equipment, machines dedicated to the sole function of cutting or machines having multiple functions.

The device 1 is provided with a tool 2 operable in rotation and in particular about a respective axis, according to a predetermined direction 3 for cutting a ceramic manufactured object 4 positioned on a working plane 5.

The tool 2 is of the grinding wheel type, but it is not excluded the use of other cutting tools operable in rotation.

Moreover, solutions which provide a plurality of tools 2 are not excluded, as solutions that foresee the use of a plurality of working planes 5 or a plurality of articles 4 on a single working plane 5 or on multiple working planes 5 are not excluded.

In the embodiment of Figure 1, the direction 3 indicates the rotation, in a clockwise direction, of the tool 2, but it is not excluded the opposite solution, i.e. the solution in which the rotation of the tool 2 is counterclockwise.

According to the invention, the device 1 comprises a cooling element 6 adapted to send compressed air or a cooling fluid at the contact area 7 between the tool 2 and the article 4.

Advantageously, the cooling element 6 is positioned at the contact area 7.

The cooling element 6 is of the nozzle type connected to a compressor and adapted to blow a jet 8a of directable compressed air.

We do not exclude different solutions whereby, for example, the cooling element 6 is a type of pipe connected to the compressor.

Always according to the invention, the device 1 comprises a cleaning element 9 with compressed air or a cleaning fluid separate from the cooling element 6.

In the present embodiment, the cleaning element 9 also has a type of nozzle adapted to blow a jet of directable compressed air 8b.

Advantageously, the cleaning element 9 and the cooling element 6 are operatively connected to the same compressor in order to blow air onto the tool 2 at the same time. We , do not exclude solutions whereby the cleaning element 9 and the cooling element 6 are connected to different compressors, or solutions whereby the same elements are able to blow air jets in an alternating manner.

Conveniently, the cooling element 6 sends or is arranged to send a jet of compressed air 8a in a direction concordant with the direction 3 of rotation of the tool 2, namely the jet 8a of compressed air is sent towards a first portion of the surface of the tool 2 with direction substantially corresponding to the tangential velocity of this first portion or inclined with respect to this velocity for an angle between 0° and 80°, preferably between 20° and 60°. According to the embodiment illustrated in the figures, the cooling element 6 is positioned in an area downstream (with reference to the direction of advancement of the objects to be processed or to the tool with respect to the objects) of the tool, or of the portion of the surface of the same, to be cooled from time to time.

Furthermore, the cooling element 6 is preferably arranged in order to send a jet 8a of air at the cutting or contact area 7 of the tool 2 with the objects, in particular, a part of the tool that, when struck by the jet 8a is in the bottom or lower position. In this regard, the cooling element 6 may comprise a nozzle with the dispensing end facing downward.

In this way it is favoured a cooling action because the jet 8a strikes the tool and continues in the direction of the contact area 7, being able to strike the surface of the tool 2 most affected by overheating.

The cleaning element 9, on the contrary, sends or is arranged to send a jet 8b of compressed air in a direction discordant with the direction 3 of rotation of the tool 2, that is to say that the jet 8b of compressed air is sent in the direction of a second portion of the surface of the tool 2 with direction substantially opposite to the tangential velocity of this second portion or inclined, with respect to this velocity, for an angle between 90° and 180°, preferably between 110° and 160°.

According to the embodiment illustrated in the figures, the cleaning element 9 is positioned in an area upstream (with reference to the direction of advancement of the objects to be processed) of the tool or of the portion of the same from time to time to be cleaned.

Clearly, the terms first and second portions indicate two portions of the perimeter surface of the tool in a respective area at a given instant, but from time to time the part of the tool that is in the area struck by the jet 8a or in the area struck by the jet 8b will vary and each portion of the outer surface of the tool will move during the rotation of the tool itself many times at the area struck by the jet 8a and at the area struck by the jet 8b.

In this way, a cleaning action is favoured because the jet 8b hits the surface of the tool 2 in countercurrent, increasing the capacity of air to remove the powdery particles that adhere to the tool itself during the cutting process.

As illustrated in Figure 1, the cooling element 6 and the cleaning element 9 are placed at different heights with one another with respect to the tool 2.

In particular, the cleaning element 9 is placed in a level higher than the cooling element 6. Additionally, the cooling element 6 and the cleaning element 9 are arranged on opposite sides with respect to the tool 2. More particularly, the cooling element 6 and the cleaning element 9 are positioned one opposite to the other with respect to a plane in which the axis of the rotation of the tool 2 lies and orthogonal to the advancing direction of the working plane 5 or of the tool 2 with respect to the working plane 5.

This positioning allows for the optimization of the cooling and cleaning actions of the device 1, making the process suitable for cutting objects made of high-resistance material such as porcelain stoneware.

In particular, the jet 8a of air from the cooling element 6 includes, in addition to the cooling action, an additional action of cleaning of the tool 2 and the jet 8b of air from the cleaning element 9 includes, in addition to the cleaning action, an additional action of cooling the tool itself.

The positioning of the cooling element 6 and of the cleaning element 9 allows the best exploitation of the combination of the above-mentioned actions.

In particular, the combination of the cooling action and the cleaning action of the jet 8a of the cooling element6 is optimised, as the combination of the cleaning action with the additional cooling action of the jet 8b of the cooling element 9 is optimised.

The operation of the present invention is as follows.

The cooling element 6 sends a jet 8a of compressed air in the direction of the contact area 7 in order to cool the tool 2 precisely where overheating occurs.

The inclination of the jet 8a and its direction concordant with the direction 3 of rotation of the tool 2 allow air sent to contact the surface of the tool 2 at the contact area 7. The action of the jet 8a, in addition, includes a first cleaning of the tool 2 by removing, from the tool 2 itself and from the working surface 5 part of the dust particles resulting from the cutting of the object 4.

The cleaning element 9, instead, sends a jet 8b of compressed air in a direction discordant to the direction 3 of rotation of the tool 2.

In this way, thanks also to the positioning of the cleaning element 9, the air sent strikes the tool surface 2 in countercurrent, after the latter has passed throughout the contact area 7. This arrangement allows both the optimization of the air resistance action on the tool surface 2, arranged to remove the dusts, and the further cooling of the same surface.

In substance, in a device according to the present invention, during the rotation of the tool, the cooling element 6 is arranged to send the jet 8a to cool portions of the surface of the tool 2 while such portions process (cut) an article and they become overheated, while the cleaning element 9 is arranged to clean (cyclically or during the rotation of the tool) portions of the tool surface that have previously, or immediately prior thereto, cut or processed an object and have previously, or immediately prior thereto, been contacted, by the jet 8a sent by the cooling element 6.

In practice, it has been found that the described invention achieves the intended purposes and in particular it is stressed that the devised device also enables the use of dry cooling systems for high-resistance materials, such as porcelain stoneware, without resorting to decreases in the velocity of rotation of the tools.

In fact, the combined use of the cooling and cleaning elements, in addition to their particular positioning with respect to the tool, allows the optimization of the cooling of the tool itself, also allowing the use of a completely dry system even in cutting high-resistance material such as porcelain stoneware.

Consequently, the device saves operating and waste disposal costs, since it does not produce sludge to be disposed of and since the powders resulting from the processing may be partly re-used or disposed of in solid form.

The invented device, moreover, allows simplification, with respect to known devices, the cooling and cleaning of the tool, by using two simple nozzles connected to a compressor.