ES2565196T3 - Printing machine for tiles and similar - Google Patents

Abstract

Tile printing machine and the like comprising a support structure (6) for a plurality of printing modules (7) comprising respective heads provided with nozzles (8) for expelling a printing fluid and means (9) for displacement of the tiles to be printed according to a direction (A) arranged under said printing modules (7), characterized in that each of said printing modules (7) is slidably associated with said support structure (6) according to a direction of sliding determined by means of guide means (13) of telescopic type comprising a stationary part (14), integrally associated with said support structure (6), and a mobile part (15), associated with said printing module (7) , in order to be able to be moved to a position outside the space occupied by said means (9) of displacement.

Description

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DESCRIPTION

Printing machine for tiles and similar Technical field of the invention

The present invention relates to a tile printing machine and the like.

State of the art

In the field of ceramic tile production and the like, inkjet printing machines are used that allow surface decorations to be obtained with high quality and repeatability.

Typically, these machines comprise one or more printing modules, for example, one for each color of the decoration, each of which is provided with a color bar which in turn contains one or more digital heads that have a large number of nozzles that eject small drops of ink that are deposited on the surface of the tile.

The objects to be printed or decorated, for example, ceramic tiles or the like, are transported on a belt or other similar means of transport through a region located below the printing modules, so that they pass next to the nozzles of the heads for a time necessary to allow the ink drops to deposit on the surfaces to be decorated.

In the known devices the printing modules are fixed close to each other to a support structure arranged on said transport means.

Because the printing modules need periodic maintenance, sufficient space is provided between the adjacent modules to allow for proper operations.

Obviously, the forecast of these spaces negatively affects the longitudinal space occupied by the

printing machine

In addition, printing machines of known type are not very versatile in terms of the exchange capacity of the printing modules, for example, when it is necessary to modify the succession of the colors deposited in each tile.

In this regard, it should be noted that the repositioning of each color bar inside the machine is not only very frequent, but also strategic to carry out a decoration, and the decoration can be carried out by addition or exclusion.

It should be taken into account that it is not possible to simply change the ink supply to a specific color bar, as cleaning problems would occur; In some cases, problems related to deposition incompatibilities due to the use of inks with different characteristics may occur.

Obviously, the repositioning of a color also requires the repositioning of the entire printing module.

Object of the invention

The technical objective of the present invention is to improve the state of the art.

Within this technical objective, an objective of the present invention is to develop a printing machine for tiles and the like capable of overcoming the aforementioned drawbacks related to the accessibility of the printing modules and their exchange capacity in a solution that involves a minimum occupied longitudinal space.

These objectives are achieved by the tile printing machine and the like according to claim 1 attached.

According to one aspect of the present invention, the machine comprises a support structure for a plurality of printing modules comprising respective heads provided with nozzles for expelling a printing fluid in the tiles, each printing module being slidably associated with the support structure according to a particular sliding direction that can be substantially perpendicular with respect to the direction of travel or which can also be different, for example, oblique with respect to the direction of travel.

In this way, the printing modules are easily accessible, being located in a position outside the space occupied by the displacement means for carrying out maintenance operations.

According to another aspect of the present invention, each printing module is associated with a respective slide carriage with respect to the support structure and houses a respective ink supply system. Said system

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Supply can be selectively connected, by quick connections, to some ink cans or other fluid cans housed in the base of the machine to change as desired the succession of colors deposited on each tile during printing.

Other advantageous features are described in the dependent claims.

Brief description of the drawings

The features of the invention will be more understandable by each person skilled in the art from the following description and from the accompanying drawings, incorporated by way of non-limiting example, and in which:

Figure 1 is a front view of the machine according to the invention;

Figure 2 is an isometric view of the machine;

Figure 3 is another isometric view of the machine from a different perspective;

Figure 4 is a schematic representation of the ink supply system of the color bar of each printing module of the machine;

Figure 5 is a rear detail view of the machine;

Figure 6 is a detail of Figure 5.

Embodiments of the Invention

Referring to the attached figure 1, the reference number 1 generally indicates a tile printing machine and the like according to the present invention.

The machine is suitable for depositing inks, enamels and other printing fluids in tiles and the like.

Therefore, from now on, the word ink will have a more general meaning, that is, each printing fluid suitable for deposition in tiles or other similar objects.

Machine 1 comprises, in a manner known per se, a frame, generally indicated as 2.

More specifically, the frame 2 comprises a base 3 with legs 4, for example, of adjustable type.

The frame 2 further comprises a box element 5 of the drawer type, arranged in the base 3, which can be used to store, for example, various containers or cans for printing fluids, spare parts for the machine, various equipment or the like, so known per se.

The machine 1 comprises a support structure 6 for a plurality of printing modules 7 housing one or more colored bars 7a, in turn provided with heads with nozzles 8 for expelling a printing fluid to be deposited in the tiles, not showing the latter in the drawings.

It is specified that the expression printing module 7 means a device designed for digital printing, normally designed to manage a single color at a time, comprising the following elements:

at least one bar 7a of digital color composed of one or more digital printheads provided with a plurality of ejection nozzles 8;

an electronic local drive unit to activate the color ejection process of the printheads;

a local fluid system comprising a double reservoir with a recirculation system; a local wiring to power the drive devices locally.

The support structure 6 of the printing modules 7 is integral with the frame 2 of the machine 1, especially in its front part.

The machine also comprises means for moving the tiles to be printed along an A direction, generally indicated as 9.

The displacement means 9 are arranged directly below the printing modules 7, as shown in Figures 1-3, so that the tiles moving in the displacement means are located at a predetermined distance from the nozzles 8 to achieve an optimal printing process.

According to one aspect of the present invention, each printing module 7 is slidably associated with the support structure 6 according to a certain sliding direction.

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For example, said direction of sliding can be substantially perpendicular with respect to the direction of travel A, with the technical advantages that will be more evident below.

Alternatively, said direction of sliding may also be different, for example, oblique with respect to direction A of travel.

It is specified that each head that makes up each color bar 7a of each printing module 7 of the machine 1 is of a type known per se in the technical field of the invention, and is suitable for expelling a controlled amount per small unit of time. drops of ink or other drops of printing fluid equivalent to deposit on the surface of the object to be printed.

Each head will not be described in more detail, since it is not an object of the present invention.

The means 9 for moving the tiles comprise a frame constituted, for example, by lateral elements 10 fixed to the central part of the frame 2 of the machine 1.

Specifically, the displacement means 9 of the tiles are of the belt type and comprise, in a known manner, drive means which can consist, for example, of a gear motor unit.

To said drive means are associated a drive roller 11 and a free roller 12, the latter being rotatably supported by the side elements 10.

A tape, not shown in the figures, wraps the rollers 11, 12, and the tiles are arranged in said tape, aligned one after the other.

The support structure 6 of the printing modules 7 is substantially in the form of a support integrated in the movement means 9.

The support structure 9 can accommodate, for example, a printing module 7 for each color used in Printing.

The printing modules 7 are juxtaposed to minimize the space between them.

In practical use, the printing modules 7 are separated by a small distance, in other words, they are separated sufficiently to allow relative displacement without friction.

According to one aspect of the present invention, each printing module 7 is associated with the support structure 6

through guide means 13.

In more detail, the guide means 13 are of the telescopic type and comprise a stationary part 14 integrally associated with the support structure 6 and a mobile part 15 associated with the printing module 7.

Each printing module 7 is substantially box-shaped and is open at the bottom to allow the nozzles 8 to expel the printing fluid.

In the embodiment shown, the stationary and movable parts 14, 15 of the guide means 13 are arranged at the bottom of each printing module 7, as specifically shown in Figure 2.

In this respect, in other embodiments not shown, the guide means 13 may be arranged on the upper wall of each printing module 7 or elsewhere according to the specific application needs.

The side walls of each printing module 7 comprise openings, preferably through openings, to allow access to each component, for example, to perform maintenance or other operations.

Specifically, for the purpose of performing maintenance operations on the selected print module 7, or possibly other machine components, the operator should only move the selected Print module 7 with respect to the support structure 6 along of the sliding direction.

In this way, the selected printing module 7 is located in a position outside the space occupied by the displacement means 9 and, therefore, is accessible frontally and laterally.

In this way, it is possible to change a color bar 7a or a single damaged head, or it is possible to carry out various maintenance or change operations, since the printing module 7 is fully accessible from all directions.

In addition, the printing module 7 and the respective color bar 7a are located completely outside the machine's operating area after its displacement: in this way, it is possible to carry out all maintenance operations without stopping the machine or the flow of tiles that pass through the machine.

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According to another aspect of the present invention, as mentioned above, each printing module 7 houses an ink supply system or other printing fluid respective to the respective color bar 7a, generally indicating as 16.

Specifically, the ink supply system 16 installed in each printing module 7 is suitable for generating a constant ink flow through the respective color bar 7a and, therefore, through the heads, so that the ink itself can be filtered continuously to retain sediments, dirt, air bubbles or any other element that can damage the color bar 7a and the heads possibly contained therein.

Said ink supply system 16 is shown schematically in Figure 4.

In more detail, the ink supply system 16 comprises a first accumulation tank 17 and a second accumulation tank 18 connected by a supply line 19 along which the color bar 7a is inserted and, therefore, Therefore, the respective printheads.

In addition, a return line 20 is arranged from the second tank 18 to the first tank 17, a recirculation pump 21 being installed along it.

The first tank 17 is open to the atmosphere through a respective evacuation opening 22, while the second tank 18 is associated with pressure control means 23 which are suitable for maintaining a pressure value inside the second tank 18 which is lower than atmospheric pressure.

The ink supply system 16 is described in more detail in European patent EP 2093065 B1, of the same applicant, which is incorporated herein by reference.

Along the supply line 19 and the return line 20, respective filters 24, 25 are disposed that remove possible foreign elements from the ink, such as sediments, air bubbles, etc.

The first reservoir 17 comprises an inlet conduit 26 through which the ink contained in a canister, not shown, is supplied into said first reservoir 17.

The canister, which contains ink or other printing fluid, can be housed, for example, inside the box element 5 arranged in the frame 2 of the machine 1.

The pressure control means 23 comprise, for example, a Venturi tube that is connected to the second reservoir 18 through a suction conduit 27 that is connected to the narrow section of the Venturi tube 23. The Venturi tube 23 is traversed by a continuous air flow to obtain a pressure drop in said narrow section and, therefore, to depressurize the second reservoir 18.

The machine 1 according to the invention comprises a circuit 28 of compressed air which, among other functions, generates the continuous air flow through the Venturi tube 23.

The part of the circuit 28 especially suitable for generating said continuous air flow is schematically shown in Figure 5, which is a rear view of the machine 1.

In more detail, circuit 28 comprises a central plate 29 that supports various components in association with means 30 for adjusting their vertical position.

Said adjustment means 30 may comprise, for example, a gear motor unit 31 associated with a spindle 32, a nut 33 connected to said spindle 32 being arranged on the central plate 29.

Alternatively, it is possible to arrange other equivalent adjustment means 30.

A manifold 34, communicated with the Venturi tube 23, is fixed to the central plate 29.

As mentioned above, the Venturi tube 23 is inserted along a line 35 of traditional compressed air, equipped with a main pump (not shown in the figures) and an emergency pump 36.

Through a first opening 37 arranged in the frame 2 of the machine 1, the suction ducts 27 connected directly to the second tanks 18 are communicated with the manifold 34.

In more detail, for each printing module 7, a collection container 38 is arranged in order to prevent possible liquid ink residues from entering the Compressed air circuit 28.

In fact, suction branches 39 are arranged that make a connection between the collection containers 38 and the manifold 34.

The communication between the various suction branches 39 and the manifold 34 is regulated by the opening and the

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respective electric valve closure 40.

According to another aspect of the present invention, the machine comprises a plurality of quick connections 41 that selectively communicate the first reservoirs 17 of each printing module 7 with the ink cans housed in the box element 5.

Said quick connections 41 allow, for example, to quickly and easily modify the sequence of the colors deposited in the tiles according to the specific production needs.

In detail, the quick connections 41 are mounted on a single support bar 42 fixed to the frame 2 of the machine 1 and they are associated with respective visual indicators 43 which have, for example, a respective serial number corresponding to that of the printing modules 7 to which they are connected.

As shown in Fig. 6, the quick connections 41 communicate the input conduits 26 (communicated with the first reservoirs 17 housed in the printing modules 7) with supply conduits 44 that are directly connected to the respective ink bottles. arranged in the box element 5.

The inlet ducts 26 reach the front part of the machine 1, where the support structure 6 is arranged, through a second opening 45 arranged in the frame 2 of the machine 1.

Also the connection between the inlet ducts 26 and the first reservoirs 17 of the printing modules 7 is carried out by rapid fluid connections.

Finally, it is specified that, as mentioned above, the printing modules 7 comprise respective electrical connection means (for example, cables, connectors and the like) to a machine control unit mounted on the frame 2 of the machine 1, of a type known per se in the field of the invention and which will not be described further, which manages the entire operation of the machine.

The electrical and electronic parts of each Print module 7 are also connected to the power supply of the machine or to the control unit through respective quick connections of known type, for example, terminals.

In the upper part of the frame 2 a control panel 46 for the operation of the machine is also arranged, associated with the control unit and other components or organs of the machine in a manner known per se.

The operation of the machine according to the invention, as well as the technical advantages achieved by the invention, are totally intuitive, as described.

The printing modules 7 eject in a calibrated and managed manner by the control unit respective amounts of ink in the form of small drops on the surfaces of the tiles that pass underneath and transported by the displacement means 9, the ink being constituted, for example, by a suspension of pigments or other similar printing fluid and enamel or the like, or by a vitreous suspension.

If one or more color bars 7a of a printing module 7 or one or more heads of the same bar 7a are not used in a printing operation, the respective ink supply system 16 keeps the ink in circulation by passing it by with respect to the color bar 7a or the head, according to the modality described in the aforementioned patent EP 2093065 B1 of the same applicant.

As mentioned above, maintenance operations on the printing modules 7 or the respective ink supply systems 16 can be carried out extremely easily thanks to the possibility of extracting each printing module 7 out of the occupied space. by means of displacement means 9, as shown in figures 2 and 3, laterally accessing the openings present.

Furthermore, thanks to the presence of the quick connections 41, it is possible to modify the sequence of the colors deposited in the tiles by the printing modules 7 as desired quickly and easily according to the specific production needs.

In other words, to modify the position of each color, that is, to modify the position of each Print module 7, it is possible to manipulate the quick connections 41 quickly and easily on the side of the ink bottles or on the side of the module. 7 Print.

It is also possible to manipulate the fast connections of the electrical or electronic parts.

All these advantages are achieved within a machine that occupies a reduced longitudinal space, that is, the space along the direction A of displacement of the tiles.

During the practical use of the machine according to the invention, the use of a certain color may be necessary for some decorations, and for others its use may not be necessary; therefore, it is especially

Frequently, it is necessary to remove and store some print modules and the respective color bars for short or long periods of time, all of which is especially easy thanks to the characteristics of the present invention.

In addition, if the decoration plant comprises more decoration machines of the same type, it is important to provide for the use of the same color bar alternatively in one machine or in another machine: this advantage is achieved thanks to the possibility of extracting the individual printing modules of the machine according to the invention.

The machine configuration allows a gradual inversion without modifying it in an invasive way: in fact, it is possible to start with a minimal trichotomy configuration (3 color bars) with the possibility, with the passage of time, of adding new bars simply by adding New printing modules.

It is clear that the invention achieves the proposed objectives.

The present invention has been described according to preferred embodiments, although it is possible to conceive equivalent variants without departing from the scope of the following claims.

Claims (11)

5 10 fifteen twenty 25 30 35 40 1. Tile printing machine and the like comprising a support structure (6) for a plurality of printing modules (7) comprising respective heads provided with nozzles (8) for expelling a printing fluid and media (9) from displacement of the tiles to be printed according to a direction (A) arranged under said printing modules (7), characterized in that each of said printing modules (7) is slidably associated with said support structure (6) according to a sliding direction determined by means of guide means (13) of telescopic type comprising a stationary part (14), integrally associated with said support structure (6), and a mobile part (15), associated with said module (7) printing, in order to be able to be moved to a position outside the space occupied by said means (9) of displacement. 2. Machine according to claim 1, wherein said sliding direction of each of said printing modules (7) is substantially perpendicular with respect to said moving direction (A) or oblique with respect thereto. 3. Machine according to one of the preceding claims, wherein said printing module (7) houses an ink supply system (16) or other respective printing fluid to at least one color bar (7a) comprising said heads . Machine according to claim 3, wherein said supply system (16) comprises a first accumulation tank (17) and a second accumulation tank (18) connected by a supply line (19) along the that said at least one colored bar (7a) is introduced, a return line (20) of said second tank (18) being arranged to said first tank (17) along which a pump (21) is installed of recirculation. 5. Machine according to claim 4, wherein along said supply line (19) and said return line (20) respective filters (24, 25) are arranged for ink or other printing fluid. 6. Machine according to claim 4, wherein said second reservoir (18) is associated with pressure control means (23) that are suitable for maintaining a pressure value lower than the atmospheric pressure inside. 7. Machine according to claim 4, wherein said first reservoir (17) comprises an ink inlet duct (26) or other printing fluid communicated with a canister housed in the frame (2) of the machine. Machine according to claim 7, comprising a plurality of quick connections (41) that selectively communicate said first deposits (17) of each printing module (7) with respective cans housed in said frame (2) to change according to it is desired to connect the supplies of the individual printing fluids to the color bars (7a) after their relocation or the incorporation of new color bars (7a). Machine according to claim 8, wherein said quick connections (41), on the side of said boats, are mounted on a single support bar (42) fixed to said frame (2). Machine according to claim 8 or 9, wherein said quick connections (41) are associated with respective visual indicators (43) that have a respective serial number corresponding to that of the Print modules (7) to the They are connected. Machine according to one of the preceding claims, wherein each of said printing modules (7) comprises means of electrical connection of the type of quick connection to a machine control unit mounted on said frame (2) and / or to the power supply of the machine.