DESCRIPTION

Technical Field

The present invention relates to the field of working blocks and slabs of stone materials such as marble, granite and the like; in particular, the object of the invention is a station for applying fluid substances, such as, although without limitation, resins, to slabs of stone material.

State of the Art

As it is well known, the natural stone materials used in the construction field, such as marbles, granites and the like, shall be mostly treated with epoxy resins, that can be single-component resins or two-component resins, so as to improve the chemical and mechanical features thereof or simply the appearance thereof. The resins enter the cracks in the slabs, thus reinforcing the slabs and giving them a homogeneous surface.

Sometimes, reinforcing webs or sheets made of artificial fibers like glass are fixed to the slabs of stone material by means of resins, to improve the mechanical performances thereof.

In general, the resin finishing is performed through process lines that, in addition to the loading and unloading operations, provide for:

· a slab drying cycle in convection ovens at the required temperature

• one or more cycles for applying the epoxy resin, also comprising, if necessary, the application of the reinforcing webs or sheets,

• a catalysis cycle in ovens at the required temperature.

In most the existing lines, the cycle for applying resins, reinforcing webs or sheets is performed manually by the operator.

Sometimes, for applying the resins a 2-axis automatic machine is used that, after having read the slab contour, sprays the resin on the slab surface by means of a pump-nozzle system.

The reinforcing webs or sheets can be also applied automatically to the slab surface, and are then covered with the resin applied manually or through the same 2-axis machine.

However, spraying the resin on the slab causes significant drawbacks from the viewpoint of both the environment and the energy consumption. In fact, even if a protection covering is made around the resin finishing area, the gaseous elements tend to exit this area or they deposit on the machine elements, thus leading, over the time, to hard deposits resulting in malfunctions of the mechanical components or in obstructions of the sucking components, with a consequent detriment of the adjacent work environment.

Moreover, this technology requires the presence of an operator. In fact, after the first resin application it is often necessary to apply the resin again in the point and cracks where it penetrated too much. In fact, in these areas the resin tends to go down with respect to the outer surface, thus making the cracks visible again. The operator shall recognize the area where the resin goes down, and shall apply thereto more resin.

Obviously, the presence of workforce is particularly disadvantageous both for environmental health questions and for the speed and quality of the intervention.

Similar problems occur with stations for applying fluid substances other than reinforcing resins, such as, for example, coloring substances, antioxidants etcetera.

Object and summary of the invention

The invention aims at solving the problems typical of the known machines and processes for applying fluid substances to stone materials.

Within this aim, an important object of the invention is to provide a station for applying fluid substances to stone materials that is suitable to reduce the need for operators when applying these substances, especially when applying reinforcing resins.

A further object of the invention is to provide a station for applying fluid substances to stone materials that allows to increase the work accuracy.

A further object of the invention is to provide a station for applying fluid substances to stone materials that is suitable to speed up the whole process.

A further important object of the invention is to provide a station for applying fluid substances to stone materials that allows to decrease the amount of used resin. A further important object of the invention is to provide a station for applying fluid substances to stone materials that allows to decrease the resin noxious emissions.

A further object of the invention is to provide a station for applying fluid substances to stone materials that is reliable and requires reduced maintenance with respect to the prior art stations.

These and other objects, that will be clearer below, are achieved by means of a station for applying fluid substances to stone materials that comprises a support surface for supporting a slab of stone material and an applicator for applying the fluid substance to the slab; the characteristic of the station is that the applicator comprises a distribution roller suitable to press the slab and to move on it to distribute the fluid substance over it, an automated moving device being also provided for moving the applicator, to allow the automated distribution of the fluid substance.

Adequately, the applicator may comprise a pressing member to press the roller against the slab, and an adjusting device for regulating the pressure of the roller on the slab.

The applicator preferably comprises a support, to which the roller is hinged, in order to allow the rotation thereof, i.e. the sliding thereof, on the slab; the pressing member comprises an actuator suitable to generate a force on the support so as to transmit the force to the roller and to generate a pressure of the roller on the slab; the adjusting device for regulating the pressure of the roller on the slab being suitable to act by regulating the force of the actuator acting on the support.

Preferably, the at least one actuator is a rotation actuator comprising a rotating member defining a power output of the rotation actuator for applying a torque; the rotating member is preferably suitable to rotate coaxially and integrally with the power axis of the rotating actuator.

Practically, the power output of the actuator rotates, differently from a translation actuator having a translating power output.

The support can adequately comprise at least one support body, to which the roller is hinged; the at least one support body is fixed to the rotating member so that, by applying a torque to the rotating member by means of the corresponding actuator, the support body and the roller tend to rotate around the axis of the rotating member, and therefore, with the roller arranged into contact with the slab and the support body arranged inclined, the direction of the torque applied to the member in the direction of movement of the roller towards the slab causes an increase in the pressure of the roller on the slab, while a decrease in the torque in this direction causes a decrease in the pressure of the roller on the slab.

The pressing member preferably comprises two rotation actuators that are arranged opposite to each other and with the axes of the respective rotating members matching the axes of the power output of the actuators, aligned to one another; a support body is integrally fixed to each rotating member, so that the roller is hinged to a pair of support bodies, that can rotate around the coinciding power axes of the rotation actuators.

In other embodiments, the pressing member comprises only one rotation actuator; to the rotating member of the rotation actuator, which defines the power output of the actuator, a shaft is fixed, which is coaxial with the rotation axis of the rotating member, i.e. with the rotation axis of the power output; a support body being provided at at least one end of the shaft, the roller being hinged to the support body; two support bodies, to which the roller is hinged, being preferably provided at opposite ends of the shaft, that are suitable to rotate integrally therewith. According to preferred embodiments, the rotation actuator is of the pneumatic type and comprises an adjusting device for regulating the actuation pressure for the compressed air.

The applicator preferably comprises a measuring device for measuring the torque applied to the shaft.

According to preferred embodiments, the applicator comprises at least one nozzle from which the fluid substance exits for being deposited on the slab, the nozzle being associated with a fluid substance supply system.

In other embodiments, the at least one nozzle from which the fluid substance exits is separated from the applicator.

In further embodiments, the at least one nozzle from which the fluid substance exits is not provided in this station but in an upstream station.

In preferred embodiments, the moving device is numerically controlled.

In preferred embodiments, the moving device provides for at least three degrees of freedom for the applicator, and in particular at least a translation parallel to the slab support surface, at least a rotation around a vertical axis, and at least a rotation around a horizontal axis.

In preferred embodiments, the moving device comprises an anthropomorphic arm, the applicator being arranged at the operative end thereof.

In preferred embodiments, the moving device comprises a carriage which is arranged above the slab support surface and spaced from this surface, from which the applicator hangs.

The anthropomorphic arm preferably hangs from the carriage; the anthropomorphic arm practically has a base fixed to the carriage, and the arm extends from the base downwards. Practically, the carriage and the anthropomorphic arm are arranged at grater height than the slab support surface; in particular, they both are arranged at a greater height than the upper surface of the slab. Therefore, having defined as construction parameter a maximum thickness of the slabs that can be processed in the station, the carriage and the anthropomorphic arm are arranged at a greater height with respect to a distance from the slab support surface equal to the maximum thickness of the slabs.

The applicator preferably has at least six degrees of movement freedom. The station preferably comprises a gantry structure provided with a crossbar arranged above the support surface, on which the carriage is arranged in a slidable way.

In preferred embodiments, the support surface is the bearing part of a conveyor belt.

The carriage can preferably translate in the direction of movement of the conveyor belt.

In other embodiments, the carriage can translate in a direction orthogonal to the direction of movement of the conveyor belt. In other embodiments, the carriage can translate both in the direction of movement of the conveyor belt and in a direction orthogonal to the conveyor belt.

The applying station is preferably a resin finishing station for applying a reinforcing resin to the stone material, and the fluid substances are therefore reinforcing resins.

According to a further aspect, the invention relates to a station for applying fluid substances to stone materials comprising a support surface for a slab of stone material and an applicator for applying the fluid substance to the slab; the characteristic of the station is that the applicator comprises a distribution blade suitable to press the slab and to move on it in order to distribute the fluid substance over the slab, an automated moving device being provided for moving the applicator, to allow the automated distribution of the fluid substance.

"Blade" means a substantially rigid member having an area extending mainly linearly and suitable to go into contact with the slab. The blade is practically a spatula for distributing the fluid substance.

Adequately, the applicator may comprise a pressing member to press the blade against the slab, and an adjusting device for regulating the pressure of the blade on the slab.

The applicator preferably comprises a support to which the blade is fixed, preferably rigidly, so as to move on the slab, touching it; the pressing member comprises an actuator suitable to generate a force on the support so as to transmit the force to the blade and to generate a pressure of the blade on the slab; the adjusting device for regulating the pressure of the blade on the slab is suitable to act by regulating the force of the actuator acting on the support.

Preferably, the at least one actuator is a rotation actuator comprising a rotating member defining a power output of the rotation actuator for applying a torque; the rotating member is preferably suitable to rotate coaxially and integrally with the power axis of the rotating actuator.

Practically, the power output of the actuator rotates, differently from a translation actuator having a translating power output. The support can adequately comprise at least one support body, to which the blade is hinged; the at least one support body is fixed to the rotating member so that, by applying a torque to the rotating member by means of the corresponding actuator, the support body and the blade tend to rotate around the axis of the rotating member, and therefore, with the blade arranged into contact with the slab and the support body arranged inclined, the direction of the torque applied to the member in the direction of movement of the blade towards the slab causes an increase in the pressure of the blade on the slab, while a decrease in the torque in this direction causes a decrease in the pressure of the blade on the slab.

The pressing member preferably comprises two rotation actuators that are arranged opposite to each other and with the axes of the respective rotating members matching the axes of the power output of the actuators, aligned to one another; a support body is integrally fixed to each rotating member, so that the blade is hinged to a pair of support bodies that can rotate around the coinciding power axes of the rotation actuators.

In other embodiments, the pressing member comprises only one rotation actuator; to the actuator's rotating member, defining the power output of the actuator, a shaft is fixed, which is coaxial with the rotation axis of the rotating member, i.e. with the rotation axis of the power output, a support body being provided at at least one end of the shaft, the blade being fixed to the support body; two support bodies, to which the blade is fixed, being preferably provided at opposite ends of the shaft , that are suitable to rotate integrally therewith. In preferred embodiments, the rotation actuator is of the pneumatic type and comprises an adjusting device for regulating the actuation pressure for the compressed air.

The applicator preferably comprises a measuring device for measuring the torque applied to the shaft.

In preferred embodiments, the applicator comprises at least one nozzle from which the fluid substance exits for being deposited on the slab, the nozzle being associated with a fluid substance supply system.

In other embodiments, the at least one nozzle from which the fluid substance exits is separated from the applicator.

In further embodiments, the at least one nozzle from which the fluid substance exits is not provided in this station but in an upstream station.

In preferred embodiments, the moving device is numerically controlled. In preferred embodiments, the moving device provides for at least three degrees of freedom for the applicator, and in particular at least a translation parallel to the slab support surface, at least a rotation around a vertical axis, and at least a rotation around a horizontal axis.

In preferred embodiments, the moving device comprises an anthropomorphic arm, the applicator being arranged at the operative end thereof.

In preferred embodiments, the moving device comprises a carriage which is arranged above the slab support surface and spaced from this surface, from which the applicator hangs.

The anthropomorphic arm preferably hangs from the carriage; the anthropomorphic arm practically has a base fixed to the carriage, and the arm extends from the base downwards. Practically, the carriage and the anthropomorphic arm are arranged at grater height than the slab support surface; in particular, they both are arranged at a greater height than the upper surface of the slab. Therefore, having defined as construction parameter a maximum thickness of the slabs that can be processed in the station, the carriage and the anthropomorphic arm are arranged at a greater height with respect to a distance from the slab support surface equal to the maximum thickness of the slabs.

The applicator preferably has at least six degrees of movement freedom.

The station preferably comprises a gantry structure provided with a crossbar arranged above the support surface, on which the carriage is arranged in a slidable way.

In preferred embodiments, the support surface is the bearing part of a conveyor belt or the like.

The carriage can preferably translate in the direction of movement of the conveyor belt. In other embodiments, the carriage can translate in a direction orthogonal to the direction of movement of the conveyor belt.

In other embodiments, the carriage can translate both in the direction of movement of the conveyor belt and in a direction orthogonal to the conveyor belt.

The applying station is preferably a resin finishing station for applying a reinforcing resin to the stone material, and the fluid substances are therefore reinforcing resins. Brief description of the drawings

Further characteristics and advantages of the present invention will be more apparent from the description of a preferred, although not exclusive, embodiment, illustrated by way of non-limiting example in the attached tables of drawing, wherein:

Fig. 1 is an axonometric view from the top of a resin finishing station for slabs of stone material according to the invention;

Fig. 2 is a front view of the resin finishing station of Fig. 1 ;

Fig. 3 is an enlargement of Fig. 2;

Fig. 4 shows the resin applicator of the resin finishing station of the previous figures, with some parts removed for making the inside thereof visible;

Fig. 5 is a front view of a variant of the resin applicator of Fig. 4, with some parts removed for making the inside thereof visible;

Fig. 6 is an axonometric view of a variant of the station according to the invention illustrated in the previous figures;

Fig. 7 is a front view of a variant of the resin applicator of Fig. 4.

Detailed description of an embodiment of the invention

With reference to the figures, number 10 indicates, as a whole, a station for applying fluid substances to a slab of stone material according to the invention. More in particular, the station is a resin finishing station for slabs of stone material.

The resin finishing station 10 is inserted, for example, within a resin finishing line, not shown in the figures, comprised of various processing stations, such as a loading station, a slab drying station (comprising, for example, one or more drying ovens), a resin finishing station, a resin catalysis station, an optional second resin finishing station with a second catalysis station, and an unloading station. Obviously, other stations can be provided in combination with those listed above.

The resin finishing station 10 may be provided with means for applying a reinforcing web or sheet to the slab, that are not shown in the figures.

The resin finishing station 10 comprises a base 1 1 integrating with a conveyor belt 12, the conveyor belt defining, at the top, a support surface 13 for the slab L of stone material, and a feed direction f from an entrance area 14 to an exit area 15 for interacting with respective processing stations of the resin finishing line.

The resin finishing station 10 also comprises a bearing structure 16, for example a gantry structure, provided with four pillars 17 arranged at the opposite ends, at opposite sides, of the conveyor belt and connected at the top by means of four crossbars 18. Between two crossbars 18, orthogonal to the slab feed direction f, the upper central crossbar 19 of the gantry structure is arranged, parallel to the direction f, preferably in correspondence of the centerline of the support surface 13. The upper central crossbar 19 is arranged spaced above the support surface 13, overlapping, i.e. intersecting, in plan, the area thereof.

A numerically controlled automated moving device 20 is associated with the upper central crossbar 19 for moving a resin applicator 21 on the slab L.

The moving device allows six degrees of freedom for the applicator 21 , as it will be better explained below. The applicator 21 hangs from the upper central crossbar 19 through the moving device 20.

The moving device 20 comprises a carriage 22 arranged slidable on the upper central crossbar 19, according to the direction g, i.e. parallel to the support surface of the slab L and parallel to the slab feed direction f. In other embodiments, the crossbar 19 may be orthogonal to the crossbar of the example above, and the carriage therefore slides orthogonally to the direction f.

On the lower part of the carriage, for example, below the upper central crossbar 19, an anthropomorphic arm 23 is provided, at the operative end 23A of which the resin applicator 21 is provided.

The anthropomorphic arm 23 comprises a base 23B articulated to the carriage 22 according to a vertical axis z. A first intermediate member 23C A is articulated to the base 213B according to a horizontal axis h; to the first intermediate member 23C, a second intermediate member 23D is articulated according to a horizontal axis h'. The operative end 23A is hinged to the second intermediate member according to an axis k orthogonal to h or h'. The applicator 21 is articulated, through a support bracket 24, to the operative end 23A according to an axis orthogonal to the axis k thereof.

The resin applicator 21 has a box-shaped central portion 25, to a part of which the support bracket 24 is fastened and with which, at opposite side with respect to the bracket 24, a resin distribution roller 26 is associated through a support to which it is hinged. In particular, the support of the roller comprises two support bodies 27, to the corresponding first ends of which the roller 26 is hinged, while the second ends thereof are integrally fixed to a shaft 28 passing inside the box-shaped central portion 25.

As it is clearly shown in Fig. 4, the resin applicator 21 also comprises a pressing member allowing to press the roller 26 on the slab L. In particular, the pressing member is embodied by an actuator 29 suitable to generate a force on the support 27-28 so as to transmit this force to the roller 26 and to make the roller press on the slab L.

Adequately, the actuator 29 is a rotation actuator whose power output is defined by a rotating member 29A (rotating coaxially and integrally with the power axis n of the actuator), to which the shaft 28 is fixed (coaxially with the rotation axis n of the rotating member 29A), allowing to generate a torque J on the shaft 28 so that, when the roller 26 contacts the slab L and the support bodies 27 of the roller are arranged inclined (i.e. with the plane where there are the hinge axis m of the roller 26 and the axis n of the shaft 28 that is inclined with respect to the support surface 13), the direction of the torque J applied to the shaft in the direction of moving the roller towards the slab causes an increase in the pressure of the roller on the slab, while a decrease in the torque J in this direction generates a decrease of the pressure of the roller 26 on the slab L.

An adjusting device is provided for regulating the pressure of the roller 26 on the slab L, suitable to act by regulating the force, i.e. the torque, of the actuator 29 acting on the support 27-28, i.e. on the set shaft-support bodies.

The actuator 29 is preferably a known rotation actuator of the pneumatic type and comprises, as well known, an adjusting device for regulating the actuation pressure for the compressed air (not shown in the figures) in the inner chambers of the actuator.

Practically, the roller 26 touches the slab. The rotation actuator 29 has a given pressure value due to the compressed air in the inner chamber thereof, to which corresponds a torsion force, i.e. a torque, at the shaft 28 in the direction of keeping the roller into contact with the slab L. Obviously, the slab transmits a strength preventing the roller from rotating around the axis of the shaft 28. By changing the pressure of the compressed air in the rotation actuator 29, the torque transmitted to the shaft 28 changes, and therefore the pressure of the roller on the slab. By setting a compressed air value in the chambers of the actuator, and keeping it constant during the resin finishing, the pressure of the roller on the slab will be substantially constant.

In Fig. 5 a variant of the resin applicator 21 is shown, and in particular of the roller pressing member. In this variant, two rotation actuators 129 are provided, fastened to the opposite flanks of the box-shaped central portion 25, and with the axes of the respective rotating members 129A matching the axes of the power output of the actuators, aligned together, i.e. they have a common rotation axis n. A support body 27 for the roller 26 is integrally fastened to each rotating member 129A, so that the roller is hinged to a pair of support bodies 27 rotating around a common axis n matching the power axes of the two rotation actuators 129. The operation is similar to that described above with reference to the single actuator with a shaft, to which the two roller support bodies are fixed. In this case, two adjusting devices are provided for regulating the pressure of the roller 26 on the slab L, suitable to act by regulating the force, i.e. the torque, of the actuators 29 on the supports 27. The resin applicator 21 also comprises a nozzle 30 from which the resin exits in order to be deposited on the slab, and which is associated with a resin supply system, not shown, comprising a pump for delivering the resin to the nozzle and one or more tanks for the resin, for example tanks for two components that are mixed before exiting from the nozzle to have a 2- component resin. Other types of resins are obviously possible.

For the sake of clarity of drawing, the compressed air system supplying the actuator, the resin supply system, and the electric system for powering the electric/electronic components of the actuator are not shown, as they are known to those skilled in the art.

Walls and a ceiling (not shown) for insulating the station are provided around the gantry structure.

Fig. 6 shows a variant of the station, indicated with number 100. The station comprises a base 1 1 integrating with a conveyor belt 12, the conveyor belt defining, at the top, a support surface 13 for the slab L of stone material, and a feed direction f from an entrance area to an exit area for interacting with respective processing stations of the resin finishing line.

The resin finishing station 10 also comprises a cantilevered bearing structure 1 16, provided with two pillars 1 17 arranged at the opposite ends of the conveyor belt, on the same side; the two pillars have two portions 1 17A projecting in a cantilevered way transversally to the direction f, above the space occupied by the surface 13, the two portions being connected together by means of an upper crossbar 1 19 that is parallel to the direction f and arranged over the space above the surface 13, preferably in correspondence of the centerline of the support surface 13.

A numerically controlled automated moving device 20 is associated with this upper central crossbar 1 19, substantially equivalent to the central crossbar 19 of the previous example, for moving a resin applicator 21 on the slab L, identical to that described above and therefore not described again.

The resin finishing station disclosed above solves the problems of the prior art stations, and have the advantages explained below.

First of all, using a distribution roller allows to distribute the resin without spraying it, thus reducing the spreading thereof in the environment.

Moreover, using a distribution roller allows to achieve an optimal resin application, avoiding any excess of resin that should be removed as well as an insufficient amount of resin, thus improving the production times and the costs.

The station structure also allows to operate in a particularly limited environment, further limiting the spreading of resin.

Using the station according to the invention allows to optimize the workforce required in the resin finishing line.

According to a further aspect, the invention provides for a variant of the resin applicator 21 that, instead of a roller, is equipped with a distribution blade 126. From a structural viewpoint, the applicator is substantially identical to the applicator of the examples above, with the only difference that, instead of the roller, a blade 126 is provided, that is integrally fixed to the support 27 (and that therefore does not rotate around the axis m, as the roller does), and that can oscillate, i.e. incline only around the axis n of the at least one rotation actuator 29. Therefore, for the description of the applicator equipped with a blade instead of a roller, reference can be made to the description (and the drawing) of the applicator described above, simply considering the blade (or spatula) 126 to be integral with the support 27 and therefore rotating only with respect to the axis of the rotation actuator (for example the blade is integrally fixed to the bar 127H integrally fixed, at the ends, to the support bodies 27).

"Blade" means a substantially rigid member having an area 126A extending mainly linearly and suitable to go into contact with the slab. The blade 126 is practically a spatula, for example made of steel, for instance harmonic steel, for distributing the fluid substance.

It is understood that what is illustrated purely represents possible non- limiting embodiments of the invention, which may vary in forms and arrangements without departing from the scope of the concept on which the invention is based. Any reference numerals in the appended claims are provided for the sole purpose of facilitating the reading thereof in the light of the description above and the accompanying drawings and do not in any way limit the scope of protection.