ES1077474U - MACHINE FOR PRINTING ON TILES AND SIMILAR - Google Patents

Abstract

1. Machine for printing on tiles and the like, comprising a support structure (6) for a plurality of printing modules (7) comprising respective heads provided with ejection nozzles (8) of a printing fluid, and some means of advancement (9) of the tiles to be printed according to a direction (A) located below said printing modules (7), characterized in that each of said printing modules (7) is associated in a sliding manner to said structure of support (6) according to a certain sliding direction, in order to be able to be moved out of the space occupied by said advancement means (9) .2. Machine according to claim 1, characterized in that said sliding direction of each of said printing modules (7) is substantially perpendicular to said advance direction (A), or obliquely with respect to it. 3. Machine according to claim 1 or 2, characterized in that said printing module (7) is associated with said support structure (6) by means of telescopic-type guiding means (13) that comprise a fixed portion (14) integrally associated to said support structure (6), and a mobile portion (15) associated with said printing module (7) .4. Machine according to one of the preceding claims, characterized in that said printing module (7) houses a respective equipment for feeding ink (16), or another printing fluid, in at least one color bar (7a) comprising said heads .5. Machine according to claim 4, characterized in that said feeding equipment (16) comprises a first accumulation tank (17) and a second accumulation tank (18), connected by a discharge line (19), along which at least said color bar (7a) is inserted, a return line (20) being provided from said second tank (18) to said first tank (17) along which a recirculation pump (21 ) .6. Machine according to claim 5, characterized in that along said discharge line (19) and said return line (20) are provided respective filters (24, 25) for the ink or other printing fluid. 7. Machine according to claim 5, characterized in that said second tank (18) is associated with pressure control means (23), capable of maintaining a pressure value lower than atmospheric. 8. Machine according to claim 5, characterized in that said first tank (17) comprises an inlet duct (26) for the ink or other printing fluid that communicates with a tank housed in the frame (2) of the machine. 9. Machine according to claim 8, characterized in that it comprises a plurality of quick connections (41) that selectively put said first tanks (17) of each printing module (7) in communication with respective tanks housed in said frame (2), with the In order to vary at will the connection of the feeds of each printing fluid to the color bars (7a) after their repositioning or the addition of new color bars (7a). Machine according to claim 9, characterized in that said quick connections (41), on the side of said tanks, are mounted on a single support bar (42) fixed to said frame (2) .11. Machine according to claim 9 or 10, characterized in that said quick connections (41) are associated with respective visual indicators (43) that indicate a respective order number corresponding to that of the printing modules (7) to which they are connected. . Machine according to one of the preceding claims, characterized in that each of said printing modules (7) comprises electrical connection means, of the quick connection type to a machine control unit mounted on said frame (2) and / or to the electrical power supply of the machine.

Description

Machine for printing on tiles and similar.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a machine for printing on tiles and the like.

STATE OF THE PREVIOUS TECHNIQUE

In the sector of the production of ceramic tiles and the like, machines are used for printing with inkjet that allow to obtain surface decorations of high quality and repeatability.

These machines typically comprise one or more printing modules, for example one for each color with which the decoration is performed, each provided with a color bar which in turn carries one or more digital heads, heads with a high number of nozzles that emit microdrops of ink that are deposited on the surface of the tile.

Generally, the objects to be printed or decorated, such as ceramic tiles or similar objects, are advanced by a ribbon or equivalent means of movement, in an area below the printing modules, so that they travel near the nozzles of the heads for the time necessary to allow the deposit of the microdrops of ink on the surfaces to be decorated.

In apparatus of known type, the printing modules are fixed side by side on a support structure positioned above said advance means.

Since the printing modules need periodic maintenance, enough space is left between the adjacent modules to allow for proper interventions.

The forecast of said spaces obviously influences negatively the space occupied longitudinally by the printing machine.

On the other hand, printing machines of known type are not very versatile from the point of view of the exchange of printing modules, for example when it is necessary to change the succession of colors deposited in each tile.

In relation to this, it is necessary that the repositioning of each color bar in the field of the machine is not only very frequent, but also strategic in order to make a decoration, where the coloring can be done both by way of addition as subtraction.

On the other hand, it should be borne in mind that it is not possible to simply vary the feed of the ink in a certain color bar, since serious problems of preventive cleaning of the same would arise; In addition, in such cases, problems of regulation incompatibility may also arise due to the use of inks with different characteristics.

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

OBJECTIVE OF THE INVENTION

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

Within the scope of said technical purpose, an objective of the present invention is to set up a machine for printing on tiles and the like capable of avoiding the above-mentioned drawbacks in terms of accessibility to the printing modules and their capacity of exchange, within the context of a solution characterized by minimum longitudinal volumes.

This purpose and this objective are achieved by the machine for printing on tiles and the like according to the attached claim 1.

According to one aspect of the invention, the machine comprises a support structure for a plurality of printing modules provided with the respective heads with ejector nozzles of a printing fluid on the tiles, in which each printing module is associated in displacement to the support structure along a certain direction, which can be substantially perpendicular to the direction of advance of the tiles, or even different, for example oblique with respect to the latter.

In this way, the printing modules are easily accessible, outside the space occupied by the machine, for maintenance operations.

According to another aspect of the present invention, each printing module is associated with a respective sliding carriage with respect to the support structure, which houses a respective ink supply equipment. The ink collection tanks, or other printing fluid, housed in the base of the machine, can be selectively connected to said feeding equipment, to change at a discretion the succession of the colors deposited in each tile during printing.

Other advantageous features are described in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the invention will become more clearly apparent to any person skilled in the art from the following description and the accompanying tables of the drawings, given by way of non-limiting example, in which:

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

Figure 2 is an axonometric view of the machine;

Figure 3 is another axonometric view of the machine, according to a different angle;

Figure 4 is a schematic representation of the ink supply equipment of the color bar of

each printing module of the machine;

Figure 5 is a rear view in detail of the machine;

Figure 6 is a detail of Figure 5.

FORMS OF EMBODIMENT OF THE INVENTION

Referring to the attached figure 1, a machine for printing on tiles and the like according to the present invention is indicated globally with 1.

The machine is suitable for depositing on tiles and similar inks, enamels or other printing fluids.

Therefore, according to the present description, the term ink must be understood in a more general sense, that is to say as any printing fluid suitable for being deposited on tiles or other similar objects.

Machine 1 comprises, in a known manner, a frame, indicated globally with 2.

The frame 2 comprises, in greater detail, a base 3 with legs 4, for example adjustable.

The frame 2 further comprises a sliding box-shaped element 5, which is supported on the base 3, which can be used to house, for example, several containers or tanks for printing fluids, machine spare parts, various tools or others, in a way already known.

The machine 1 comprises a support structure 6 for a plurality of printing modules 7, which house one or more colored bars 7a, in turn provided with heads provided with respective ejector nozzles 8 of a printing fluid to be deposited on the tiles, the latter not being represented in the figures.

It is required that a printing module 7 means a device intended for digital printing, generally intended for managing one color at a time and consisting of the following elements:

at least one digital color bar 7a, in turn composed of one or more digital printheads, in turn provided with a plurality of ejector nozzles 8;

a local electronic control unit, to pilot the color ejection process of the printheads;

a local fluid equipment, comprising a double tank with recirculation system;

a local electrical installation, for the local power supply of the actuators.

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

The machine also includes advance means, indicated globally with 9, of the tiles to be printed according to a direction A.

The advancing means 9 are placed directly below the printing modules 7, as illustrated in Figures 1 to 3, so that the tiles moving on said means are at a predetermined distance from the nozzles 8, for Get an optimal printing process.

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

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

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

It is necessary that each head that makes up each color bar 7a of each printing module 7 of the machine is of the type already known in the sector and is capable of dispensing a controlled amount, in the unit of time, of ink drops or of other equivalent printing fluid, intended to be deposited on the surface of the object to be printed.

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

The advancing means 9 of the tiles comprise a frame formed, for example, by stringers 10 fixed to the central part of the frame 2 of the machine 1.

The advancing means 9 of the tiles are especially of the type of belt and comprise, in a known way, drive means that can be formed, for example, by a geared motor group.

To said drive means are associated a motor roller 11 and a driven roller 12, the latter rotatably supported by the beams 10.

On the rollers 11, 12 a tape is wrapped, not shown in the figures, on which the tiles lie, aligned one behind the other.

The support structure 6 of the printing modules 7 is substantially formed by a console, positioned in a cantilever position on the advancing means 9.

The support structure 6 can accommodate, for example, a printing module 7 for each color used in printing.

The printing modules 7 are arranged side by side, in order to limit the space between them to a minimum.

During use, the printing modules 7 are arranged at a short distance from each other, that is to say the distance necessary to allow reciprocal movement without dragging.

According to one aspect of the present invention, each mobile printing module 7 is associated with the support structure 6 by means of the guiding means 13.

In more detail, the guiding means 13 are of the telescopic type and comprise a fixed portion 14 joined in solidarity with the support structure 6, and a mobile portion 15 associated with the respective mobile printing module

7.

Each mobile printing module 7 has a substantially open-box conformation at the bottom, which allows the flow of printing fluid dispensed through the nozzles 8.

In the embodiment shown, the fixed and mobile portions 14, 15 of the guiding means 13 are provided in correspondence with the bottom wall of each printing module 7, as can be seen in particular in Figure 2.

In other embodiments not shown, however, the guiding means 13 could be provided in correspondence with the upper wall of each printing module 7 or in other parts thereof, in relation to the specific application requirements.

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

In particular, to perform the maintenance of the parts of the selected print module 7, or possibly other machine components, it is sufficient to remove the print module 7 in question from the support structure 6, in the sliding direction. In this way, the selected print module 7 will be outside the space occupied by the advance means 9 and is accessible both frontally and from the sides.

In this way, for example, a colored bar 7a or a single damaged head can be replaced, or several maintenance or replacement operations can be carried out on other components, with maximum accessibility to all parts of the printing module 7.

On the other hand, the printing module 7 and the relative color bar 7a, after translation, are completely outside the machine's operating area: in this way, maintenance operations can be performed without having to stop the machine and the flow of the tiles that cross it.

According to another aspect of the present invention, as indicated above, each printing module 7 houses a respective ink feeding equipment, or other printing fluid, indicated globally with 16, in the respective color bar 7a.

In particular, the ink feeding equipment 16 installed in each printing module 7 is capable of generating a constant flow of ink through the respective color bar 7a and therefore through the heads, so that the same ink can be continuously filtered to retain possible sediments, dirt, air bubbles or any other element that could damage the color bar 7a and the heads.

Said ink feeding equipment 16 is schematically illustrated in Figure 4.

The feeding equipment 16 comprises, in greater detail, a first accumulation tank 17 and a second accumulation tank 18, connected by a discharge line 19, along which the color bar 7a and the relative heads are inserted of impression.

In addition, a return line 20 of the second tank 18 to the first tank 17 is provided, along which a recirculation pump 21 is installed.

The first reservoir 17 is open to the atmosphere by means of a respective purge port 22, while the second reservoir 18 is associated with means for controlling the pressure 23, which are suitable for maintaining a pressure value inside. lower than atmospheric

Ink feed equipment 16 is described in detail in European Patent EP 2 093 065 B1 of the same applicant, incorporated herein by reference.

Along the discharge line 19 and the return line 20, respective filters 24, 25 are provided, which are responsible for cleaning the ink of possible foreign elements, sediments, air bubbles, etc.

The first reservoir 17 comprises an inlet conduit 26 by means of which the ink contained in a tank, not shown, will feed the interior of the same first reservoir 17.

The ink tank, or other printing fluid, can be, for example, placed inside the sliding box-shaped element 5 in the frame 2 of the machine 1.

The pressure control means 23 comprise, for example, a Venturi tube, which is connected to the second reservoir 18 by means of a suction conduit 27 which flows in correspondence with the restricted section of the Venturi tube 23. By the Venturi tube 23 a continuous air flow is passed, in order to obtain a decrease in the pressure in said restricted section and therefore to depress the second reservoir 18.

The machine 1 according to the invention comprises a compressed air circuit 28 which is responsible, among other things, for generating the continuous air flow through the Venturi tube 23.

The portion of the circuit 28 especially intended to generate said continuous flow is schematically represented in Figure 5, which constitutes a rear view of the machine 1.

The circuit 28 comprises, in greater detail, a central plate 29 for supporting the different components, associated with means for regulating 30 of the vertical position.

Said regulating means 30 may comprise, for example, a gearmotor group 31 associated with a screw 32, a nut 33 being provided on the central plate 29 coupled to said screw 32.

Alternatively, regulation means 30 of another equivalent type can be used.

A manifold 34 is attached to the central plate 29 which communicates with the Venturi tube 23. The latter, as already mentioned, is inserted along a traditional compressed air line 35, provided with a main pump - not visible in the figures. -and of an emergency pump 36.

By means of a first opening 37 provided in the frame 2 of the machine 1, the suction ducts 27 connected directly to the second tanks 18 are placed in communication with the collector

3. 4.

In more detail, a respective collection vessel 38 is provided for each printing module 7 whose function is to prevent possible ink liquid residues from accidentally remaining inside the compressed air circuit 28.

For this purpose, suction branches 39 are provided that bring the respective collection vessels 38 into communication with the collector 34.

The communication between the different suction branches 39 and the manifold 34 is regulated from respective opening or closing solenoid valves 40.

According to another aspect of the present invention, the machine comprises a plurality of quick connections 41 that selectively bring the first reservoirs 17 of each printing module 7 into communication with the ink tanks located in the sliding box-shaped element 5.

These quick connections 41 allow, for example, to quickly and easily change the sequence of colors deposited in the tiles, in relation to the specific production requirements.

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

As illustrated in Figure 6, the quick connections 41 communicate the inlet ducts 26, which lead to the first reservoirs 17 located in the printing modules 7, with feed ducts 44 that are directly communicated with the respective tanks of ink provided on the element in the form of a sliding box 5.

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

Even the connection between the inlet ducts 26 and the first reservoirs 17 of the printing modules 7 is made by means of quick 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 the type already known substantially in the sector and which will not be described in detail, which manages the entire operation of the machine.

Even the electrical and electronic parts of each printing module 7 are connected to the machine feeder or to the control unit by means of corresponding quick connections - for example clamps of known type.

In addition to the upper part of the frame 2, a control panel 46 of the operation of the machine 1, associated with said control unit and other components or organs of the machine, is provided in a known manner.

The operation of the machine according to the invention is, based on what has been described, completely intuitive, as well as the technical advantages achieved by the invention.

With the passage of the tiles transported by the advancing means 9, the printing modules 7 dispense, in a calibrated way under the management of the control unit, respective amounts of ink - formed for example by a suspension of pigments - or other printing fluid such as an enamel or the like - formed, for example, by a glassy suspension - in the form of micro-drops that are deposited on the surface of the tiles.

If one or more color bars 7a of a printing module 7, but also one or more heads of the same bar 7a, are not used in the printing operation, the respective feeding equipment 16 is responsible for keeping the ink in circulation skipping the color bar 7a or the head, according to the modes described in said patent EP 2 093 065 B1 of the same applicant.

As already mentioned, maintenance operations on the printing modules 7 or on the respective ink feeding equipment 16 can be carried out extremely easily thanks to the possibility of extracting each mobile module 7 out of the space occupied by the means of advance, as illustrated in figures 2, 3 accessing laterally to the planned openings.

On the other hand, thanks to the presence of the quick connections 41, the succession of the colors deposited on the tiles by the printing modules 7 can be varied at the discretion quickly and simply, in relation to the specific production requirements.

In other words, to change the position of each color, that is to say to change the position of each printing module 7, it is possible to intervene quickly and easily on the quick connections 41, both from the side of the ink tanks and from the print module side 7.

On the other hand, you can quickly intervene in the fast connections of the electrical and electronic parts.

5 All these advantages are achieved within the scope of a machine with limited volumes in the longitudinal direction, that is in the direction of advancement A of the tiles.

Within the scope of the use of the machine according to the invention, the use of a certain color may be necessary for some decorations, for others, on the contrary, its use is not provided; therefore the need to remove and store for more or less prolonged periods is especially frequent

10 certain printing modules together with the color bars, which is especially easy given the characteristics of the invention.

In addition, if more decorating machines of the same type are present in the decoration equipment, it is important to be able to plan the use of the same color bar alternatively on one or another machine: this advantage is obtained thanks to the possibility of removing each module printing machine according to the invention.

15 The configuration of the machine is such that it allows a gradual investment without having to make invasive modifications of it: you can start with a minimum configuration in trichromia -3 color bars-leaving the possibility of adding new bars with only Add new printing modules.

It has thus been seen how the invention achieves the proposed objectives.

The present invention has been described according to preferred embodiments, but equivalent variants can be devised without thereby departing from the scope of protection offered by the following claims.

Claims (12)

1. Machine for printing on tiles and the like, comprising a support structure (6) for a plurality of printing modules (7) comprising respective heads provided with ejector nozzles (8) of a printing fluid, and about feed means (9) of the tiles to be printed according to one direction (A) located below said printing modules (7), characterized in that each of said printing modules (7) is slidably associated with said support structure (6) according to a certain sliding direction, in order to be moved out of the space occupied by said advance means (9).

2.

Machine according to claim 1, characterized in that said sliding direction of each of said printing modules (7) is substantially perpendicular to said advancing direction (A), or oblique with respect thereto.

3.

Machine according to claim 1 or 2, characterized in that said printing module (7) is associated to said support structure (6) by means of guiding means (13) of telescopic type comprising a fixed portion (14) associated in solidarity to said support structure (6), and a movable portion (15) associated with said printing module (7).

Four.

Machine according to one of the preceding claims, characterized in that said printing module (7) houses a respective ink feeding equipment (16), or other printing fluid, in at least one color bar (7a) comprising said heads .

5.

Machine according to claim 4, characterized in that said feeding equipment (16) comprises a first accumulation tank (17) and a second accumulation tank (18), connected by a discharge line (19), along which at least said color bar (7a) is inserted, a return line (20) of said second tank (18) being provided to said first tank (17) along which a recirculation pump (21) is installed ).

6.

Machine according to claim 5, characterized in that along said discharge line (19) and said return line (20) are provided respective filters (24, 25) of the ink or other printing fluid.

7.

Machine according to claim 5, characterized in that said second reservoir (18) is associated with means for controlling the pressure (23), capable of maintaining a lower than atmospheric pressure value inside.

8.

Machine according to claim 5, characterized in that said first reservoir (17) comprises an inlet conduit (26) of the ink or other printing fluid that communicates with a tank housed in the frame

(2) of the machine.

9.

Machine according to claim 8, characterized in that it comprises a plurality of fast connections (41) that selectively communicate said first tanks (17) of each printing module (7) with respective tanks housed in said frame (2), with the in order to vary at discretion the connection of the feeds of each printing fluid to the color bars (7a) after repositioning or the addition of new color bars (7a).

10.

Machine according to claim 9, characterized in that said quick connections (41), on the side of said tanks, are mounted on a single support bar (42) fixed to said frame (2).

eleven.

Machine according to claim 9 or 10, characterized in that said quick connections (41) are associated with respective visual indicators (43) indicating a respective order number corresponding to that of the printing modules (7) to which they are connected.

12.

Machine according to one of the preceding claims, characterized in that each of said printing modules (7) comprises electrical connection means, of the type of quick connection to a machine control unit mounted on said frame (2) and / or to the machine's power supply.