TECHNICAL FIELD The present invention relates to an automatic selecting and handling device for assembling mosaic-like objects.

More particularly, the present invention relates to an automatic selecting and handling device for objects substantially consisting of a unit for selecting and repositioning tesserae, a unit for the selective supply of tesserae, and a collection unit comprising a line of trays in which the selected tesserae are positioned.

The new feature proposed by the present invention substantially relates to the possibility of fully automated assembly of both partially and completely different mosaic tesserae, by setting the choice of colours directly on a monitor connected to a processor. The automatic handling device which receives the data from the processor performs repeated repositioning operations to allow the pick up parts to selectively pick up the tesserae and place them in succession in the lower tray.

The present invention is applied in the sector for the production of automated machinery for repositioning objects, hi particular mosaic tesserae or the like.

BACKGROUND ART

It is known that in the construction sector and hi particular in the coverings sector, some types of walls, both interior and exterior, are made by assembling tesserae in mosaics. In many cases, if not most, the tesserae of which the mosaic is composed are selected and combined with one another from a vast range of colour combinations, to achieve shaded, variegated, design results, and even the actual composition of figures. At present, some machines are commercially available which automatically assemble mosaics. Said machines consist of a gantry structure on which a head equipped with an oscillating arm slides, with parts for picking up the tesserae arriving from a hopper vibrator located opposite the arm, to transfer the tesserae onto a collection tray.

However, according to these known solutions, it is not possible to assemble mosaics which are shaded, multicoloured and variegated, nor is it possible to achieve modelled figure effects, forming a mosaic, but only assembly of mosaics with substantially uniform colour or at most with a shaded effect obtained by adjusting only the method for supply of the various tesserae.

The fact remains that all other types of mosaics, that is to say, variegated ones and above all with designs and figures, are still created manually by trained personnel, with all of the practical difficulties and all of the notoriously high costs deriving from the use of skilled labour.

DISCLOSURE OF THE INVENTION

The aim of the present invention is to make available an automatic selecting and handling device for assembling mosaic-like objects which can overcome or at least reduce the above-mentioned disadvantages. Another aim of the present invention is to provide an automatic selecting and handling device for assembling mosaic-like objects with a construction that is simple, yet effective from the point of view of the result achieved relative to the finished product. This is achieved with an automatic selecting and handling device for assembling mosaic-like objects whose characteristics are described in the main claim.

The dependent claims for the solution disclosed describe advantageous embodiments of the invention.

The main advantages of this solution, in addition to those deriving from its simple construction, relate firstly to the fact that such a machine allows the fully automated assembly of both partially and completely differentiated mosaic tesserae by setting all of the parameters and the choice of colours directly on a monitor connected to a processor with suitable software.

The automatic handling device which receives the data from the processor is equipped with an operating head able to perform repeated fully automated repositioning operations, to allow the pick up parts to selectively pick up the tesserae and place them in succession in the lower tray.

One of the main characteristics of this system may be considered the head unit,

mounted on a sliding beam and with a volume created on it for the vacuum shared by a plurality of solenoid valves, so that a vacuum cylinder can be supplied through each of these.

The operating head, sliding on the beam, selectively picks up the tesserae from the multiple-hopper supply unit, to assemble a simple mosaic which may, approximately, be of the size having 144 tesserae with 12x12 rows, with tessellation of from 2 to an infinite number of colours, and with a joint between tesserae measuring approximately 2 mm. When assembling two or more colours, a base colour is required and the remaining colours must be positioned randomly, but without creating so-called "patchy zones". This effect is eliminated with predetermined selection from a table of colours and the respective tones. In the board of 144 positions there will be a preview of the result to be obtained, then during positioning of the colours on the board, dialog with the PLC will allow the handling device to select the tesserae from the system stand by positions.

The equipment consists of eight main units, two of which may vary for customised sizes. The eight units are as follows:

1. Conveyor belt;

2. horizontal axis Y for positioning and pick up; 3. vertical axis Z for suction cups;

4. axis W for suction cup head rotation;

5. suction cup pick up head unit;

6. axis E for conveyor lifting;

7. tesserae recognition and repositioning unit; 8. tray pick up handling device axis X.

The tesserae pick up head unit is the characteristic part of the invention and consists of a plurality of suction cups located on two distributors, typically of the 12+12 way type, which allow the supply of a vacuum to each suction cup line, where each line is controlled by a solenoid valve located on the board of the axis Z. The head is designed to pick up from the special conveyors the tesserae indicated by the program and is built for a size system.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the invention are evident in the description which follows, of a preferred, non-restricting embodiment of the invention, with reference to the accompanying drawings, in which: - Figure 1 is a schematic side view of the machine in accordance with the present invention, wherein a first group of axes is indicated;

- Figure 2 is a schematic front view of the machine, highlighting the axis of movement Y of the head carriage;

Figure 3 is a schematic front view of the operating head and of the respective operating connections;

Figure 4 is a schematic plan view of the operating head slidably mounted on the beam;

- Figures 5 and 6 are schematic side views of the machine in a first and a second step of tesserae pick up from the distribution device and hopper; - Figures 7 and 8 are schematic plan views of the machine during the same operating steps as illustrated in the two previous figures; Figure 9 is a detailed schematic view of the machine operating unit, that is to say, the tilting head located on the supporting and sliding beam;

- Figures 10 and 11 are respectively schematic side and plan views of the tesserae recognition and repositioning device;

Figure 12 is a schematic view of the recognition and repositioning device applied to the machine;

- Figure 13 is a schematic and perspective view of an alternative embodiment of the head; - Figures 14 and 15 are respectively schematic side and perspective views of an alternative embodiment of the feed device and belts;

- Figure 16 is a schematic front view of the machine in which the tray unit has a transversal movement device on the axis "Q";

- Figure 17 is a schematic and perspective view of a device for placing tesserae according to an alternative embodiment with a continuous conveyor belt tray;

- Figures 18 and 19 are schematic views of the machine according to the invention as a whole according to said alternative embodiment with a

continuous conveyor belt tray.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION With reference to the accompanying drawings, the automatic selecting and handling device according to the invention for assembling mosaic-like objects consists of eight main units, two of which may vary for customised sizes.

The eight main units are, therefore, firstly a conveyor belt 10 located at the bottom and bearing a set of trays 11 which are fed forward at regular intervals, a unit with an axis Y comprising a horizontal beam 12 on which a carriage 13 is mounted bearing a head 14 for positioning and picking up tesserae.

The head 14 in turn can move on a vertical axis Z to place the tesserae on the trays and can also move at an angle on axis W to shift from a horizontal tesserae pick up position to a vertical position angled downwards for placing the tesserae picked up on the tray.

The numeral 15 denotes as a whole a unit for supplying tesserae consisting of hoppers which move vertically on the axis E, comprising a tesserae recognition and repositioning unit.

Finally, the axis labelled X is for movement of the tray pick up handling device 16. The gluing units and tray insertion units are not mentioned, since they are added according to the specifications of the production line and are not an integral part of the automatic device.

More precisely, the horizontal beam 12, on which a carriage 13 bearing a head unit

14 for tesserae positioning and pick up is mounted, comprises a linear guide system and ball screw and brushless motor movement parts, which move the carriage 13 board horizontally where the axis unit Z, the axis W and the suction cup pick up head

14 unit is located.

The head unit 14 is mounted on a shaft 14' and consists of two distributors which may be of the 12+12 way type, allowing a vacuum to be supplied to each suction cup line, each line being controlled by a solenoid valve located on the carriage 13 board.

The head 14 is designed to pick up the tesserae indicated by the program from special supply unit 15 conveyors and is built for a size system.

Controlled axis movement allows the positioning in the sequences predetermined by the software of the numbered suction cups opposite the selected colour channel of the conveyor.

The head 14 may perform angular rotations of approximately 90° on the shaft 14' to move from a substantially horizontal position opposite the tesserae arriving from the supply unit 15 to a vertical position pointing downwards to move towards the placing zone on the lower tray 11.

The angular rotations of the head 14 on the axis W are allowed by a cylinder and a connecting rod - crank labelled 17 in Figure 3, allowing the 90° rotation of the suction cup pick up head unit on the shaft 14'.

The innovative feature of the system disclosed may be considered the head unit itself. A volume is created for the vacuum shared by the twenty-four solenoid valves, so that a vacuum cylinder can be supplied through each of these.

Each line is controlled by a pressure regulator and the suction cup unit is supplied by a distributor with independent lines which allow the head to rotate and at the same time supply the vacuum to each suction cup. This distributor is located on the shaft

14' designed to also form the pivot for unit rotation, as is clearly illustrated in Figure

4.

The board supporting the head unit 14 with axis of rotation W moves on axis Z which uses a system of linear guides 18 with pneumatic movement by means of a rotary cylinder. The vertical axis of movement Z allows the head 14 to be positioned, once the twenty-four tesserae have been picked up, above the tray 11 for insertion of the tesserae.

To sum up, the head 14 can perform angular movements of 90° on the axis W, vertical movement on the axis Z and horizontal movements on the axis Y together with the carriage 13 which supports it.

Opposite the pick up unit of which the head 14 is part, there is, as indicated, the supply unit labelled 15 as a whole. The supply unit 15 consists of one or more hoppers 19, each comprising tesserae of different colours. Respective conveyor chutes 20 extend from the hoppers downwards.

Each conveyor with the respective hopper may move vertically on the axis E so as to

position the conveyor for formation of the second row, once the first row, having already been picked up by the head suction cups, is complete. This movement is driven by a fixed-stroke pneumatic cylinder 21.

On the end of each conveyor chute there is a window-like opening 22 facing the head 14, which the tesserae give onto for pick up by the head 14 suction cups.

The tesserae recognition and repositioning unit is located in the supply unit 15 and close to the upper part of the conveyor chute 20. Said unit allows recognition of the painted and unpainted face, then inverts the position.

The tesserae recognition and repositioning unit, designed to present the tesserae with the painted face on the side opposite the suction cup pick up device, uses a rotary template 23, a chute 24 from which the tesserae drop, whilst the conveyor chute 20 has a wheel 25 operating in conjunction with a pneumatic tipper piston 26.

The tesserae recognition and repositioning unit also comprises a luminescence sensor, whilst the pneumatic cylinder 26 is designed to supply every colour to be inserted in the finished product.

Finally, the conveyor belt 10 consists of an aluminium structure with two belts, one in front of the other, driven by a motor. Between the two belts there is a brake/clutch system which makes it possible to keep the outfeed belt moving continuously and when the clutch engages to move the infeed belt for the time needed to position the tray.

This construction method was designed so that the movement speeds of the infeed and outfeed belts must be equal.

The stop 16 is positioned between the conveyor belt and the machine load-bearing structure. It is designed to stop the tray when it reaches the position indicated by a sensor, then to operate with a pick up system and move the tray independently of the belt, so that each head completion cycle corresponds to a predetermined step.

The system consists of a controlled axis and the stop 16 pick up action is performed with a system of pneumatic cylinders 23.

The machine described allows the automatic assembly of a simple mosaic which approximately and generally consists of 144 pieces with 12x12 rows, and with tessellation of from two to an infinite number of colours. The mosaic tesserae may have a joint between them measuring approximately 2 mm.

A composition with two or more colours must have a base colour and the remaining colours must be positioned randomly, but without creating "patchy zones". This effect is eliminated with the predetermined choice from a table of colours and respective tones. In the board of 144 positions there will be a preview of the result to be obtained, then during positioning of the colours on the board, dialog with the PLC will allow the handling device to select the tesserae from the system stand by positions. The colours must be set on the screen, each colour having a corresponding number. They will then be inserted in a graphic cell of 144 positions, also having position numbers.

The following is a brief description of the sequence of machine operating steps:

1. Formation of the first block of 12 suction cups, each suction cup having a vacuum ON/OFF solenoid valve;

2. axis Y is repositioned according to the data entered and until the first row of 12 is completed;

3. the tesserae conveyor is raised to compose the second row of 12 suction cups, the same operation as in points 1 and 2 takes place until the second row is complete;

4. -90° rotation of the axis W;

5. downward movement of the axis Z; 6. all 24 suction cups release their load;

7. movement of the axis Z to 0°;

8. return rotation of the axis W;

9. during the operations in points 4 to 7 the conveyor returns to the lowered position;

10. the operation from points 1 to 8 is repeated 6 times, equal to the complete assembly of a tray;

11. during the tray assembly operation, before the conveyor the tessera direction check is performed, using a SENSIK type reading sensor for colour and luminescence, which sends a signal to a pneumatic cylinder that, when activated, turns the tessera to the correct position. The speed of this system is greater than the operation for assembly of each block of twenty-four tesserae, thus creating a system with build-back in the conveyor chutes;

12. the axis X is managed by a single motor which keeps the tray picked up moving

continuously, during the operation positioning is performed every 27 mm six times, the movement is performed with a controlled axis;

13. on the edge of the belt there is a photocell for the start and end of tray transit, which then indicates the feeding forward of the next tray; 14. the paper gluing unit, if present, is at the end of the conveyor belt.

As can be seen, this machine offers infinite possibilities for the management of tesserae colours, and in theory could be used for assembling mosaics with complex designs and figures.

It is sufficient to compose the figure on the monitor and the system then operates fully automatically to place the selected tesserae on the tray.

In an alternative embodiment of the automatic handling device described and illustrated, the sliding axis X for tray feed may be positioned on the head unit and in this case the trays are not fed forward but the entire head unit moves with the beam

12 on special sliding lanes. Figure 13 illustrates a handling head 27 which can spin around on the supporting blocks 28 and 29. In this case the head has a plurality of independent suction cup lines 30 arranged on the various angular sectors of the head.

Figures 14 and 15 illustrate a tesserae feed device according to an alternative embodiment. In said embodiment the feed unit 31, which the tesserae reach from one or more vibrating hoppers 19, is without conveyor chutes 20.

In this case, the chutes are substituted by continuous loop belt lines 32 arranged parallel with one another and driven by motors 33. The tesserae 34 are fed forward on the belts and picked up by the suction cups on the head 14. Figure 16 illustrates a machine according to the invention equipped with an auxiliary movement device, that is to say, on the transversal axis "Q", which uses a movement device 35 suitable for moving the trays even transversally relative to their forward feed line. This type of movement on the axis "Q" allows the trays to be fed forward and to be moved, so as to achieve substantially circular tray movements.

Figure 17 illustrates a continuous tray device 36. The tray on which the head places the tesserae in this case consists of a belt line shaped with a grid with continuous

forward feed located between two or more rollers 37 and 38. Belt forward feed is driven by a motor-powered drive unit located at one of the two rollers. The machine described may also handle any object whether in the ceramics sector or any other sector, for example the sector for stone materials in general, but also in the pharmaceutical sector and that of distribution of products to be sorted by means of preselection.

The automatic handling device described may also be used for selectively handling objects of various consistencies, whether rigid or soft, and even for handling fabric of various consistencies and any type of material. Finally, the shaft which supports the head can rotate the handling head 14 through a complete round angle of 360°.

Advantageously, in addition to using vacuum cylinders, the tesserae pick up method may use pneumatic cylinders, that is to say, cylinders pressurised rather than containing a vacuum, or electromagnet movement units. The invention is described with reference to a preferred embodiment. However, it shall be understood that there may be many alternative embodiments of the invention, using technical equivalents without thereby departing from the scope of the inventive concept.