WO2008149392A1

WO2008149392A1 - Method and unit for applying a flexible adhesive film or label on a product

Info

Publication number: WO2008149392A1
Application number: PCT/IT2007/000399
Authority: WO
Inventors: Gianluca Pizzo; Luciano Morini
Original assignee: Victrix Group S.R.L.
Priority date: 2007-06-06
Filing date: 2007-06-06
Publication date: 2008-12-11

Abstract

An application unit (1) for a protection and support flexible adhesive (3) on a product (5;50;500) sliding on a transport means (7), including: at least one moveable grasping device (23) able to grasp one end of the edge of said label (3); at least one transfer device (21) which serves to move said label (3) from said grasping device (23) onto a visible side of said product (5;50;500); transport means (17; 18) to move said grasping device (23) from the grasping position towards said transfer device (21); at least one guide (24; 24B) to guide and keep said label (3) stretched during the movement of said grasping device (23).

Description

"METHOD AND UNIT FOR APPLYING A FLEXIBLE ADHESIVE FILM OR

LABEL ON A PRODUCT

DESCRIPTION Technical field This invention deals with a machine for applying a protective and supportive flexible adhesive label on a product or handiwork, a relevant method of application of said label and a finished product with improved features and quality.

State of the art From time immemorial mosaic handiworks have been known realized with tesserae or details of even modest size, for example of only a few tens of millimeters on the side, for wall tiles or floor tiles for decorative purposes.

These tesserae have a decorated side, which can be colored, shiny, enameled, and which usually forms an ornamental design visibly applied on the wall or floor.

Patent IT-B-01244110 discloses a method to produce tessera panels for mosaics in which a series of tesserae are laid out with the visible side facing upwards on a level to form a panel: said panel is taken with a sucker and laid on a support in sheet or mesh of paper or other material after having spread the lower face of the panel and/or the upper face of the support with glue; later a flow of hot air from the bottom to the top heats the lower surface of the panel drying the glue.

This method serves to automate the application of a sheet of paper or mesh on the invisible side of the tesserae of a panel for mosaics. Patent EP-B-1179439 discloses a machine for producing tessera panels for mosaics, in which at least one film or support is applied onto a visible side of the tesserae laid inside a frame, which includes devices to feed and devices to apply said support together with the feeding movement of the frame wherein the application devices include cutting equipment for cutting a part of the film and a rotating drum with suction holes on its external surface to hold, at least temporarily, the cut part of the film and release it on the mosaic tesserae of the panel.

A disadvantage of this kind of machine is that it is not possible to accurately control the forward movement of the film, in particular of large size films, so the finished product can present imperfections and irregularities, such as creases or bubbles of film, compromising the adherence of the tesserae to the film itself and the quality of the finished product.

Another disadvantage is that it is not possible to accurately control the laying of the film on the moving tessera panel, so imperfections or irregularities can occur, in particular with particularly small or unstably shaped tesserae.

Furthermore, laying of the film on the moving tessera panel is particularly delicate and difficult as the tesserae can be moved by the drum creating a

"domino effect" or chain effect, creating random irregularities between the joints between tessera and tessera; the finished product therefore is of poor quality and its laying on a wall proves difficult.

To this day, despite technological developments, there is a need to provide simple low cost machines to produce tessera panels for mosaics in an even faster and more economic way realizing a better finished product of high quality.

Objects and summary of the invention

One object of an embodiment of the invention is to provide a machine for applying protection and support labels on a product or handiwork, which is more economic and of simpler construction and that overcomes or alleviates some of the disadvantages outlined above.

A particular object of an embodiment of the invention is to provide an application unit to automatically apply a protection and support flexible adhesive label on a product, particularly on a tessera panel for mosaics but not only, in a way that is more precise and faster and a relevant method of application. Another object is to provide a tessera panel for mosaics with better quality and features.

According to a first aspect, the invention provides a machine or unit for applying adhesive labels on a product movable along a direction of forward movement on a conveyer, which includes in combination: at least one mobile grasping device, to grasp the labels; and at least one transfer device to transfer the labels from the grasping device onto a surface of the product, said grasping device being mobile from a label pick-up position towards a position where the labels are released to said transfer device.

According to a preferred embodiment of the invention, the machine or unit includes at least one guiding device to guide and keep the labels stretched out during the movement of the grasping device.

The grasping device, the guiding device and the transfer device are able to grasp the label when open or flat without ruining or damaging it. In the preferred embodiment of the invention, the grasping device includes one or more pneumatic grasping elements, for example vacuum suckers, to suck air to hold the edge of the label.

The grasping device can include one or more mechanical grasping elements, for example pliers or similar, as an alternative to or in combination with the aforementioned pneumatic grasping elements.

In an advantageous embodiment of the invention, a number of grasping elements are associated on a first supporting element transversal to the direction of movement of the panel, to grasp the edge of the label keeping it stretched and avoiding the formation of creases and irregularities; in this way it is also possible to grasp labels of various shape, that is with edges even largely irregular, as it is sufficient that only some of the grasping elements grasp the edge, see description further down.

The transfer device includes advantageously and preferably at least one tilting and movable transfer level to transfer the open or stretched out label onto the surface of the product; also said transfer level can include at least one pneumatic or mechanical transfer element, for example a pneumatic extraction system or mechanical pliers or the like, as an alternative to one another or in combination with one another, see further down.

In an advantageous embodiment, the transport means include a couple of lateral and opposite transport guides between which the moving grasping device and transfer device are positioned.

The guiding device can be advantageously realized with at least one pneumatic guide, for example a guiding nozzle to blow in air towards one face of the open label to guide it and keep it stretched out during the movement, particularly avoiding the formation of creases and irregularities during the movement from the grasping position towards the transfer device; it should not be excluded that the guiding device can also include at least one mechanical guide like pliers or the like, as an alternative to or in combination with the aforementioned pneumatic guides. The protection and support adhesive flexible label is advantageously and preferably shaped and reproduces the geometric form of the surface onto which it has to be applied; therefore it can present a regular geometric form like for example square or rectangular or any other shape, like a letter of the alphabet or a design with complex edges or other, see description further down.

Advantageously, the flexible label is fed continuously to the application unit, preferably on a continuous film from which the label is stripped by means of a stripping blade.

Furthermore, it can be also envisaged to obtain - for example through die-cutting - a number of shaped flexible labels in succession on a continuous film along the direction of movement of the film; the flexible film can also be advantageously associated in a detachable way to a lower support.

In this last case, the flexible film is preferably fed to the application unit by means of a stripping machine to divide continuously and automatically each label from the film and from the lower support, see further down.

Even though it would be possible to foresee the use of various materials to manufacture the flexible label and relevant continuous film, for example paper or fabric, according to a particularly advantageous embodiment of the invention the label is made of plastic and preferably a transparent, semi transparent or translucent plastic material; the support is also advantageous and preferably in plastic, flexible and transparent or opaque, such as for example of silicon paper or kraft paper; it is not to be excluded that the label, the flexible film and/or any support can be realized with more than one layer each of which can be of different materials to have an overall specific thickness, like for example from a minimum of 1 micrometer to 500 micrometers or preferably from 40 micrometer to 250 micrometers, or even more preferably from 140 micrometer to 250 micrometers.

The plastic material is particularly resistant to traction and therefore makes the removal of the label after laying of the tessera panel simpler. The label has an adhesive on its lower face, which can be acrylic or rubber based or other suitable adhesive and serves to glue said labels to the surface of the product in a detachable manner; when the lower support is envisaged this adhesive also serves to glue the label to said support in a detachable way. It should be noted that though the application unit according to the invention is particularly advantageous when fed with labels made of a continuous film as described above, it is not to be excluded that the labels can be fed to the application unit in a different way, for example without realizing them on the continuous film and/or without including the lower support.

An advantage of one embodiment of the invention is that of automatically applying a shaped support and protection label on a surface of a product more precisely and accurately than the traditional machines.

In particular, with such an application unit it is possible to very accurately control both the forward movement and laying of the label onto the surface of the product, thus increasing considerably the precision of the application.

Therefore, it is possible to apply labels on surfaces of products even with forms or edges of complex geometry, which are difficult to process automatically with machines currently available on the market; furthermore, it is possible to work with glues or materials of different kinds, which may have different dimensions and strengths, without compromising the quality of the finished product, see also description further down.

Another advantage of one embodiment of the machine according to the invention is that it is possible to process large-size shaped labels, for example of several hundreds of millimeters of side, automatically and continuously, achieving a high production rate and high quality of finished product.

Specifically, it is possible to control the formation process of the undulations on the label in an improved manner, critical for this kind of processing, compensating the stress and decreasing the friction, so it is possible to work at much higher speeds avoiding damage or breakage of the material and increasing machine output.

A further advantage of an embodiment is that it is possible to envisage labels with elements in pre-established and set positions on their surface like for example one or more openings or holes of appropriate shape and size or lateral non-adhesive tear strips or with printed matters, as for example a brand or a logo or alphanumeric strings such as bar codes or similar, without running the risk that such print can be unusable because interrupted or shown in an incomplete way on each label.

Summarizing, such an ' application unit permits to automatically apply adhesive labels on particularly delicate and/or fragile products, as for example tessera panels for mosaics, permitting to obtain at the same time a finished product of innovative features and which at the same time have a high level of personalization and quality. According to a different aspect, this invention deals with a method for applying a shaped protection and support label on a surface of a product moveable along a direction of forward movement, characterized by including the following phases: feeding said labels in open or flat configuration along a feeding route with a feeding speed; grasping said labels and transporting them along a first positioning direction; depositing said shaped labels on said product moving them along a second positioning direction. According to an embodiment, the invention foresees a method including the following steps: taking said labels individually by means of a grasping device; transferring said labels by means of said grasping device along a first path towards a transfer device; - engaging said labels by means of said transfer device; transferring said labels through said transfer device to said products.

The invention will be described below with specific reference to the application in the field of the ceramics industry, for application of protection and/or support adhesive labels on the visible sides of mosaic tesserae. Nevertheless, the invention can be used in different fields, where similar problems can occur.

A panel of pre-ordered tesserae for laying mosaics with a protection and support shaped adhesive label also forms part of the invention applied in a detachable way on the visible side of said tesserae, in which said tesserae are small or light or in any case unstable, like for example tesserae which present at least one dimension much larger than the others.

According to a possible embodiment, the label applied to the tessera panel can have a geometric form with dimensions equal to those of said panel or with slightly smaller dimensions, so as not to project from the edges of the panel itself. Furthermore, the label can have a series of openings or aeration holes positioned on some of the joints between adjacent tesserae, or preferably on a number of crossovers of the joints between adjacent tesserae and/or a non-adhesive tear tongue in a pre-established position and/or print in a preset position.

In one embodiment the tessera or tile panel has a number of interlocking projecting parts each formed with a number of said tesserae. The projecting interlocking parts are able to interlock the panel with adjacent panels to create a continuous decorative composition on a wall. The projecting parts can be covered by the label in a way that keeps the tesserae that compose it united. On the part of the label above the projecting parts further elements are envisaged, like for example the aforementioned openings and/or the aforementioned printed matter or other.

In one embodiment the projecting parts have an external rectangular, curved or sinuous or in any case articulated perimeter, realizing appropriately the form of the most external tessera.

In one embodiment the tessera panel includes a main body formed by central tesserae and at least one projecting part formed with a number of intermediate tesserae shaped in a way to form an internal rounded-off or curved corner and a number of external tesserae shaped to realize a rounded-off end with a semicircular segment.

The label can also be applied on the same panel with a small margin of edge of appropriate dimensions to keep the tesserae joined to one another.

Further advantageous features and embodiments of the invention are indicated in the attached dependent claims and will be further described below with reference to some non-limitating examples of embodiment. Brief description of the drawings

The invention can be better understood and its numerous objects and advantages will become clear to those expert in the field with reference to the attached diagrammatic drawings, which show a practical non-limiting example of the invention. In the drawing:

Fig. 1 shows an axonometric view of a machine according to one embodiment of the invention;

Fig. 2 shows an enlarged axonometric view of a detail of Fig. 1 ; Fig. 3 shows a partially enlarged view of a detail of Fig. 1 ;

Fig. 4 shows a section according to line IV-IV in Fig. 1 ;

Figs 5A and 5G show subsequent application steps of a protection and support label on a tessera panel for mosaics according to the invention; Fig. 6 shows a tessera panel according to one embodiment of the invention;

Fig. 7 shows a feature of the tessera panel of Fig. 6; according to a partially modified embodiment. Detailed description of embodiments of the invention In the drawings, in which equal numbers correspond to equal parts in all the different figures, an application unit according to the invention is indicated by 1 and has the purpose of applying a shaped protection and support label 3 on a tessera panel 5 for mosaics which moves on a conveyer belt 7 along a direction of forward movement F1. The application unit 1 includes two lateral support surfaces 1 P fixed to a frame 7T on opposite sides of the conveyer belt 7 by means of a fixing system with slots 15, which serves for a first manual adjustment of unit 1. On each lateral surface 1P a respective lateral transport guide 17 is mounted, on which a first support element 11 slides, said element being formed by an upper support arm transversal to the direction of forward movement F1 of panel 5. A series of grasping elements 23 described in greater detail below are associated to said support element 11.

The lateral transport guides 17 are inclined by about 30 degrees in relation to the direction of forward movement F1. This inclination can be adjusted manually by an operator for adapting to specific processing needs. In one embodiment the lateral transport guides 17 can be parallel to conveyor belt

7.

The support element 11 is moveable on the lateral guides 17 through a sliding or movement system 18 actuated by a motor 31. In the embodiment shown in the drawing, the system 18 includes a transmission belt 18A on each side of the unit, entrained around guide rollers 18B, one of which is motorized by means of a motor 31 , and forming a linear path along each lateral guide 17. A cable-carrying chain 18G serves to guide electric cables and pneumatic pipes for the grasping devices 23 avoiding crushing or interferences. The sliding system 18 is purely shown as an example, since it can be of any other kind suitable for the purpose.

Fig. 2 shows an enlarged axonometric view of the grasping elements 23. In one embodiment, said grasping elements 23 include a series of pneumatic suckers distanced one from the other on the support element 11.

Indicatively, grasping suckers 23 can be twenty on a 400 mm long support element 11. The diameter of the contact surface of suckers 23 with the label can be about 6 mm. It is clear that such data are indicative of one embodiment of the invention and are in no way limitative. Suckers 23 are in fluid connection with a pneumatic system 63 - see again Fig. 2- and can be formed by a plastic deformable cap to tightly grasp a portion of the shaped label 3 without causing damage to the material.

It is not to be excluded that grasping elements of another kind may be envisaged, like for example mechanical pliers, positioned on the support element 11 or laid out in another way, alternatively or better in combination with the aforementioned suckers 23.

The device includes a number of guide elements 24 schematically represented by a series of pneumatic guiding nozzles distanced one from the other on the lower support element 12, transversal to the direction of forward movement F1. This lower element 12, is positioned offset below the upper support element 11. The label 3 is positioned between the suckers 23 and the nozzles 24.

Indicatively, guiding nozzles 24 can be twenty on a 400 mm long lower support element 12. Their diameter can be approximately 1 mm. It is clear that such data are indicative of one embodiment of the invention and are in no way limitative.

Also in this case, it should not be excluded that other kinds of guide elements may be envisaged, such as for example mechanical pliers, positioned on the lower support element 12, or along the lateral guides 18 or again laid out in another way, alternatively or better in combination with guiding nozzles 24.

To connect the ends of the upper element 11 and lower element 12 in a sliding manner, on guides 17 are lateral slides 25 right and respectively left sliding on guides 17, on which further supports or brackets 26 are mounted in a rotating or oscillating manner by means of rotating joints 28. In particular, support levels 26P are envisaged on oscillating brackets 26 to support first actuators 27 mechanically connected to a respective end of the upper element 11 , to move it along a positioning direction F3. The first actuators 27 can be pneumatic pistons, hydraulic jacks, electric motors or other. The rotating joint 28 includes a rotation mechanism with a return spring - not shown in the figure for simplicity - and at the lower end of each guide 17 a mechanical stop 17B is provided, which cooperates with a respective stop 26B of each oscillating bracket 26.

Therefore, oscillating brackets 26 rotate on a transverse axle, i.e. parallel to the axle of element 11 , against the force of the return spring when they reach the lower end of each guide 17, to orient the suckers 23 according to an approaching direction F3, see also Fig. 5C and 5D.

It should not be excluded that such a mechanism of rotation be realized in any other way suitable for the purpose. In this way grasping of shaped label 3 and functioning of said grasping elements 23 are optimized, as it is possible to adjust and register the approaching direction F3 on the basis of the specific needs of each process.

Furthermore, it is also possible to guide and accompany label 3 in a very gradual way during any stripping, without creating variable or discontinuous tension and stress which could damage or tear it.

Fig. 2 also shows, by way of example, a pneumatic circuit 63 including a feed pump 65 in fluid connection with the grasping suckers 23 through a first Venturi tube 67 and a first flexible pipe 7OA. Pump 65 is also in fluid connection with nozzles 24 through a second flexible pipe 7OB. The Venturi tube 67 is fed by the pump 65 with pressurized air, for example at approx. 6 bar, to create a suction to operate the grasping suckers 23. It should be noted that to vary the suction of suckers 23 the Venturi tube can be simply replaced with another suited to providing the desired vacuum, without further work being required on the circuit. The Venturi tube operates in a known manner: a fluid flow, in this case air, passes through a throttle inside said tube and is discharged in the atmosphere producing a suction which sucks the air required to create the vacuum through channel 7OA.

The pneumatic circuit 63 shown in Fig. 2 envisages a control system including a control unit 69 connected to a first and a second valve 71 A and 71 B to control the activation of the grasping suckers 23 and the guiding nozzles 24 respectively through signals from a first sensor S1 and a second sensor S2.

The first sensor S1 can be a knock sensor positioned on the mechanical stop 17B to activate the suckers 23 as soon as they reach this position. In this case the duration of operation of suckers 23 can be set manually by the operator.

In a different embodiment, the first sensor S1 can be a pressure sensor to detect a vacuum value - settable by the operator - to indicate that the suckers 23 have grasped the label; in this case the suckers 23 can be activated at the end of a time interval, which can be manually set by the operator.

The second sensor S2 can be an infra-red, magnetic or similar presence sensor, positioned at a final end of the first positioning direction F3 on transfer device 21 , to detect the suckers 23 and control their deactivation, as described below. In this way it is possible to produce a pneumatic circuit and a relevant control system which are extremely easy to maintain and use, with low cost and at the same time versatile in use. It is clear that the pneumatic circuit and the relevant control system can be designed differently, and therefore they are indicative and non-limitative for this invention. Fig. 3 shows an enlarged section of the transfer device 21 , which includes a tilting mobile level vertically movable along a second positioning direction F5 by means of a second actuator 47 and furthermore hinged around a rotation axle 33, which is transversal with respect to the direction of forward movement F1 of the panel 5 by means of a third actuator 49. The transfer device 21 is positioned between guides 17 and extends along the first positioning direction. The stroke of the suckers 23 is such to exceed (moving along direction F4) the position in which the transfer device 21 is arranged, to allow the suckers 23 to lay the label 3 on the lower surface of the level 21. The actuators 47 and 49 can be pneumatic pistons, hydraulic jacks or electric motors. It is clear, however, that such actuators 47 and 49 can be realized with any other system suited to the purpose, like for example mechanical actuators with belts or chains or with toothed wheels or other.

The transfer device 21 includes an upper closing metal sheet 35 fixed on a container 37 with an internal cavity 37A and a lower surface 37B with a number of holes 41 with a diameter of about 1 mm. A closing gasket 43 is envisaged between the upper closing metal sheet 35 and the container 37 to seal cavity 37A while a contacting gasket 45 in "mousse" rubber or the like, is envisaged on lower surface 37B to facilitate adhesion and subsequent detachment of the label 3.

The contacting gasket 45 is provided with openings 41 B tapered or shaped in correspondence of each hole 41 , to create a vacuum inside said openings 41 B to improve the grasp of label 3 holding it more stably on the gasket 45.

Fig. 3 shows furthermore another branch of the pneumatic circuit 63, which serves to connect the pump 65 (Fig. 2) to the cavity 37A through a second Venturi tube 68 and a flexible pipe 7OC connected to a suction hole 36, to create a vacuum to hold the label 3 against the contacting gasket 45. A valve 71 C upstream of Venturi tube 68 is connected to unit 69 to control the suction of the transfer system 21.

Furthermore, a pressure sensor can be provided - not shown in the figure for simplicity - in cavity 37A to detect a vacuum degree settable by the operator to indicate that the transfer device 21 has grasped the label 3. It is to be noted that the pump 65 could be replaced by a small compressor. In this case a Venturi tube could be provided on pipe 7OB to transform the vacuum into a current of pressurized air for nozzles 24, while the suckers 23 and the cavity 37A can be directly connected to the compressor.

Fig. 4 shows a vertical section of the unit 1 , in which a movement system for the transfer device 21 is shown, including a support 52 with a double T- shaped transversal profile, see also Fig. 1 , at which ends are connected vertical guides 51 sliding within a supporting transverse beam 53 also transversal and fixed to the lateral walls 1 P. The second actuator 47 is mounted on traverse beam 53 and has one mobile end fixed centrally to the support 52 to move it along the second positioning direction F5. The rotation axle 33 of the transfer device 21 is provided on the ends of the support 52 opposite to those where guides 51 are fixed. Furthermore an oblique arm 49A is fixed on said support 52 to support the third actuator 49 in an offset position with respect to axle 33 and permits rotation of the transfer device 21 around said axle 33. It should be noted that it is possible to manually adjust the height of the vertical guides 51 and therefore of the transfer device 21. It is also possible to regulate the inclination of the transfer device 21 depending on the specific construction or process needs (for example depending on the inclination of guides 17).

It is clear that the aforementioned movement system of the transfer device 21 is described indicatively, as it can be of any kind suited to the purpose.

Fig. 4 also shows part of a stripping machine which serves to strip or separate the label 3 from a continuous film 3F on which it is die-cut and from a lower support 3S, if provided, by means of a stripping blade 55.

In particular, in this case, a number of labels 3 are die-cut in succession on the film 3F and each label 3 is separated automatically and gradually from the film 3F (by breaking the die-cutting lines) and from its lower support 3S at the end of the blade 55. In this case blade 55 defines the direction of feeding F2 of label 3.

The height and inclination of the stripping blade 55 can be adjusted with respect to the direction of forward movement F1 of panel 5 to adapt to different processes, in particular to panels of different height. More specifically, the stripping phase shown in the figure envisages that the support 3S folds below the blade 55 to wind around a rewinding roller - not shown in the picture - downstream of the feeding path, while the label 3 continues to move above a support element 57 which serves to keep the edge just stripped of label 3 raised, making the grasping thereof by means of the grasping suckers 23 easier, see also description further below.

In the embodiment shown, the support element 57 is formed by an anti- adherent sheet metal - for example with a pebble surface-connected in an adjustable way by means of a telescopic rod 59 to the stripping blade 55 in a way to allow manual setting of the distance and inclination of the support element 57 with respect to the stripping blade 55 depending on the specific processing.

It should not be excluded to design the support element in another way, like for example with thrust nozzles not shown in the figure for simplicity, to blow air from the bottom to support and push the edge of the label 3 towards the suckers 23, as an alternative to or in cooperation with the aforementioned support element 57.

Figs. 5A to 5G show subsequent processing steps of the application unit 1 described to here. In particular, in said figures, labels 3 are fed to the application unit 1 automatically and continuously through a stripping machine of the kind partly shown in Fig. 4. It is not to be excluded - as mentioned further above - that the unit 1 be associated to any other feeding machine to supply any other kind of labels and/or film continuously and/or automatically. Initially, manual calibration or adjustment of the unit 1 is envisaged to set the grasping position of the suckers 23 above the support element or sheet metal 57, bringing unit 1 close to the stripping machine by acting on slots 15 and/or adjusting the inclination of the guides 17 and/or the position of mechanical stop 17B on respective guide 17. Fig. 5A shows a first step, in which the label 3 (detached from the film 3F and from the lower support 3S) is fed with a feeding speed VA according to the direction of feeding F2 along the path defined by the stripping blade 55, at the end of which the stripping occurs. In this step the suckers 23 are brought close to the point of stripping X, see Figs. 5B to 5D, on lateral guides 17 along a first positioning directionF4. Axle 9A of the grasping suckers 23 is approximately perpendicular to direction of positioning F4.

Fig. 5B shows a subsequent phase to that of Fig. 5A in which stop 26B of the oscillating brackets 26 hits the mechanical stop 17B at the lower end of the guide 17 and grasping suckers 9 rotate according to arrow F6 to position themselves in the approaching direction F3, see Fig. 5C, against the force of the return spring of the joint 28.

The approaching direction of F3 can be adjusted initially so that axle 9A is approximately perpendicular to the feeding path F2 or approximately perpendicular to the support element 57 or in another way to optimize grasping and stripping, if provided.

Fig. 5C shows the subsequent step, in which the grasping suckers 23 move downwards along the approaching direction F3 by means of the first actuator 27 and are activated to suck air to tightly grasp the stripped end of the label 3. It should be noted that said grasping can be realized without suckers 23 pressing on support element 57. The edge of label 3 can be kept lifted by the jet of air of any guide nozzle 24, not shown in Fig. 5A-5G for simplicity.

Both the actuator 27, the suckers 23 and any nozzle 24 can be activated by the unit 69 on command of sensor S1 , i.e. detecting when stop 26B hits stop 17B, or using other systems of activation depending on specific construction needs. In this step the label 3 stops to guarantee a better grasp by suckers 23. It should not be excluded that grasping occurs with label 3 in movement. A presence sensor, like for example an ultrasound sensor or a feeler, not shown in the Figure for simplicity, can be positioned on tilting blade 55 to detect the presence of the edge of the label 3 under suckers 23. Fig. 5D shows a subsequent step, in which the suckers 23 move upwards along the approaching direction F3 with the end of label 3 tightly grasped.

In this case it is noted how in the stripping position X a flexion on label 3 is created which facilitates its gradual detachment from film 3F (breaking any point of die-cutting) and from any lower support 3S. Fig. 5E shows a subsequent phase in which label 3 advances gradually by means of the grasping suckers 23 along the first positioning direction F4 below transfer device 21. In this step the label 3 is already completely stripped, i.e. detached from the film 3F. Guiding nozzles 24 are activated by blowing in air below the lower surface of the label 3 to guide it, support it and keep it stretched along the direction F4. The axle 9A of suckers 23 is approximately perpendicular to guides 17. Furthermore, the tilting level of the transfer device 21 is arranged approximately parallel to the first direction F4, i.e. to guides 17.

It should be noted that during the gradual detachment of the label 3 from the film 3F, the speed V2 with which the grasping suckers 23 move along the first direction F4 can be adjusted such as to coincide with the feeding speed VA of the film 3F or in a way to be slightly higher, to put label 3 in slight traction in relation to the film 3F and facilitate the stripping, depending on the material of label 3 and the type of glue used.: In an alternative embodiment of the invention, where it is not envisaged to realize labels 3 through die-cutting of the film 3F, in this phase a transversally sliding blade to cut film 3F and obtain a single label can be envisaged.

Fig. 5F shows a subsequent step in which suckers 23 have been deactivated and distanced from the edge of the label 3. At the same time the vacuum is generated in the inside of cavity 37A of the tilting level of the transfer device 21 to withhold label 3 on its lower surface 37B which is in fluid connection with cavity 37A through holes 41 , see Fig. 3. Further guiding nozzles 24B are activated to blow in air from below towards the edge of the label 3 just released from the grasping suckers 23 to facilitate suction of said edge by the level 21.

Deactivation of the suckers 23 and activation of the transfer device 21 and further nozzles 24B can be controlled by the unit 69 thanks to the sensor S2 positioned at the end of the first direction F4 on transfer device 21. Said sensor S2 is adjusted during the initial calibration step, so that the label 3 can be applied on panel 5 of the tesserae below with a minimum waste.

Fig. 5G shows a subsequent step to that of Fig. 5F, in which the tilting level of the transfer device 21 is rotated with respect to the axle 33 - see arrow F7 - by means of the actuator 49 to lay out parallel to panel 5. Subsequently it is lowered by means of the actuator 47 along the second positioning direction F5 to position the label 3 on the visible side of the tessera panel 5.

In this step, the tessera panel 5 is stopped below label 3 held by the level of the transfer device 21 thanks to a stop 61 with electric mechanical sensor which detects its presence and stops the motion of conveyor belt 7. The stop 61 can also be adjusted manually to increase the precision of the application. Reference number 62 indicates an actuator, in the example a piston-cylinder actuator, which controls the movement of the stop 61 to move it away from the trajectory of the panels 5, allowing continuation of the movement of each panel beyond the label application unit, after the respective label 3 has been applied to it.

A movement sensor - not shown in the Figure for simplicity - serves to stop the movement of the level of the transfer device 21 along the second direction F5 depending on the height of tessera panel 5, so as not to press it or crush it avoiding to compromise the reciprocal position of the tesserae. Furthermore, it is possible to facilitate the detachment of label 3 from the tilting level of the transfer device 21 and at the same time gluing thereof on the panel 5 by means of a high pressure blow from the said holes 41 , avoiding that the tilting level of the transfer device 21 presses on tessera panel 5.

Fig. 6 shows an embodiment for a tessera panel 50 including a number of tesserae T which have a height H1 greater than base B1 and width L1 , on the visible side on which is applied the adhesive label 3. The label 3 has a series of aeration openings F positioned on some of the joints of tesserae T or preferably on a number of crossovers of said joints and it also has a non-adhesive tear tongue G in a preset position on the edge of panel 50 and a print P in a preset position. Furthermore, the panel 50 has a plurality of interlocking projecting parts Z1, each formed by a plurality of tesserae T, which have the function of interlocking the panel 50 with adjacent panels, such as to achieve a continuous decorative composition on a wall on which said panels have to be applied. Specifically, said projecting parts Z1 have an essentially rectangular external form or perimeter and are covered by the shaped support and protection label 3 to keep the tesserae T which compose it united; other elements can further be envisaged, like for example holes F, on the portion of the label 3 extending above the projecting part Z1. The projecting parts Z1 can have another kind of external perimeter, such as e.g. curved or sinuous, or in any case articulated, realizing appropriately the shape of the most external tesserae.

The shaped label 3 therefore has a size exactly equal to that of tessera panel 50 or, advantageously, a slightly smaller dimension but which allows to keep all tesserae T of panel 50 united, including those of the most external edge.

In this way a tessera panel for mosaics can be realized with a more pleasing appearance and at the same time simpler, more economic and faster in laying on a wall, as label 3 does not have zones or parts projecting beyond the perimeter or projecting from the edge of panel 50, i.e. parts of the label not glued on the tesserae, which should be cut before laying adjacent panels on a wall.

The abovementioned tessera panel 50 can be advantageously and preferably realized automatically with one application unit 1 of the kind described above, it is not in any case excluded that such panel 50 can be realised in another way.

Fig. 1 also shows panel 5 with a circular ring form which envisages tesserae with a width L2 greater than the base B2 and height H2.

Fig.7 shows a detail of a panel 500 including a number of main tessarae T to form a central body, advantageously all of the same shape but not only, and a projecting part Z2 realized with a number of intermediate tesserae T1 and T3 and two external tesserae T2 shaped to form a rounded-off end of the projecting part Z2 with a semicircular segment. Some of the intermediate tesserae - those indicated with T3 in the figure - are also advantageously shaped to form an internal curved or rounded-off corner. A shaped label 3 is applied on the visible side of all these tesserae, T, T1 , T2, and T3 with a small perimeter margin M which keeps them united.

It is understood that what is illustrated are only possible non-limitative embodiments of the invention, which can vary in forms and arrangements without departing from the concept underlying the invention. Any presence of reference numbers in the claims attached have the sole purpose of facilitating their reading in view of the description which precedes and of the drawings attached and does not limit in any way the scope of protection.

Claims

1) A unit to apply adhesive labels onto a product moving along a direction of forward movement on a conveyer, characterized by t including:

- at least one mobile grasping device, to grasp said labels; - at least one transfer device to transfer said labels from the grasping device onto a surface of the product, said grasping device being mobile from a label pick-up position towards a position where the labels are released to said transfer device.

2) The application unit according to claim 1, characterized by including at least one guiding device to guide and keep the labels stretched out during the movement of said grasping device.

3) The application unit according to claim 2, characterized in that at least one guiding device includes at least one pneumatic guide element, to blow in air towards an open face of said labels to guide them and keep them stretched out during the movement of said grasping device.

4) The application unit according to claim 2 or 3, characterized in that said guiding device includes at least one mechanical guide.

5) The application according to one or more of the preceding claims, characterized by including a transport device for moving said grasping device from the taking position towards said transfer device.

6) The application unit according to claim 5, characterized in that said transport device includes a couple of lateral and opposing guides, between which is arranged said at least one mobile grasping device movable along said guides; said transport device including a movement system for moving said at least one grasping device along said guides.

7) The application unit according to one or more of the preceding claims, characterized in that said grasping device includes at least one pneumatic grasping device.

8) The application unit according to claim 7 characterized in that said grasping device includes at least one sucker.

9) The application unit according to one or more of the preceding claims, characterized in that said grasping device includes at least one mechanical grasping device.

10) The application unit according to one or more of the preceding claims, characterized in that said mobile grasping device can assume at least two distinct angular positions around an oscillating axle substantially transversal to the direction of forward movement of the product, to engage the labels and pass the labels to the transfer device. 11) The application unit according to claim 10, characterized in that said oscillating axle is substantially parallel to said conveyor.

12) The application unit according to one or more of the preceding claims, characterized by including an upper support element, transversal to the direction of forward movement of the product, to which is associated said at least one grasping device; said upper support element being mobile towards said transfer device.

13) The application unit according to claims 10 and 12, characterized in that said upper support element is oscillating around said oscillation axle substantially transversal to the direction of the forward movement of the product.

14) The application unit according to claim 13, characterized by including a number of said grasping devices, aligned and distanced one from the other on said upper support element.

15) The application unit according to at least one of the claims 2 to 14, characterized by including a lower support element transversal to the direction of forward movement of said product and to which is associated at least one guide.

16) The application unit according to claim 15, characterized by including a number of said guide elements, aligned and distanced one from the other on said lower support element.

17) The application unit according to claims 12 and 15, or 12 and 16, characterized in that said lower support element is positioned offset below said upper support element and mobile with it.

18) The application unit according to claim 17, characterized in that said lower support element and said upper support element are connected to one another, the upper support element being angularly mobile with respect to the lower support element.

19) The application unit according to claims 6 and 18 characterized by including lateral moving slides on said guides, which rigidly support said lower support element; and wherein on said slides oscillating brackets are supported, which hold said upper support element.

20) The application unit according to claim 19, characterized in that said upper support element is mobile in relation to the oscillating brackets, to approach and distance itself from the labels.

21) The application unit according to claim 19 or 20, characterized in that the oscillation of said brackets is controlled by a fixed stop on a support structure, the oscillation being caused by the approaching movement of the slides carrying the brackets along said guides towards the fixed stop . 22) The application unit according to one or more of the preceding claims, characterized in that said transfer device includes a pneumatic label retention system.

23) The application unit according to one or more of the preceding claims, characterized in that said transfer device includes at least one transfer level mobile from one position of receipt of labels from said grasping device to an application position of said labels to said product, said transfer level being able to engage and transfer said open or stretched out labels onto the surface of said product.

24) The application unit according to claim 23, characterized in that said transfer level is tilting.

25) The application unit according to claim 24, characterized in that said transfer level is tilting around an axle which is essentially horizontal and transversal to the direction of forward movement of the product.

26) The application' unit according to one or more of claims 23 to 25, characterized in that said transfer level includes an internal cavity with a lower suction surface, on which aid labels adhere in flat or stretched out attitude.

27) The application unit according to one or more of claims 23 to 26, characterized in that said transfer level includes a contacting gasket, in rubber or similar, on said lower surface, to facilitate adhesion and subsequent detachment of the labels.

28) The application unit according to claim 27, characterized in that said contacting gasket is apertured with tapered or shaped openings in correspondence of the suction holes to create a depression within said openings to improve the retention of said labels keeping them more stable on said gasket.

29) The application unit according to at least claims 3 and 7, characterized by including a pneumatic circuit with a feed pump which generates a flow of compressed air for said guiding device and which, through a Venturi tube, generates a suction effect in said grasping device.

30) The application unit according to claims 22 and 29, characterized in that said pneumatic circuit includes a further Venturi tube to generate, through said pump, a suction effect in said internal cavity of the transfer level.

31) The application unit according to one or more of the preceding claims, characterized by including at least one support element to support the edge of said labels facilitating their grasp by said at least one grasping device.

32) The application unit according to claim 31 characterized in that said support element includes an anti-adherent sheet-metal.

33) The application unit according to claim 31 or 32, characterized in that said support element includes a pneumatic system to blow pressurized air to support the edge of the label.

34) The application unit according to one or more of the preceding claims, characterized by including a stripping device to automatically detach or strip a series of said labels arranged in succession on a continuous film; grasping of such labels through at least one grasping device occurring during stripping.

35) The application unit according to claim 34, characterized in that said stripping device includes a stripping blade, along an edge on which said continuous film, on which said labels adhere, is guided. 36) A method for applying labels onto a surface of a product mobile along a direction of advance movement, characterized by including the following steps: feeding said labels in an open or flat position along a feeding path with a feeding speed; - grasping said labels and transporting them along a first positioning direction; laying said shaped labels on said product moving them along a second positioning direction. 37) Method according to claim 36, characterized in that said labels are fed sequentially, automatically by means of a continuous film onto which they adhere and are individually detached from said film.

38) Method according to claim 37, characterized by including at least one grasping device which grasps the labels close to the area in which they are detached from the film and transports them along said first direction of forward movement.

39) Method according to claim 38, characterized by gradually advancing said labels by means of the movement of said grasping device along the first positioning directionand transfer the labels below a transfer device, said transfer device engaging said labels to transfer them to said product.

40) Method according to claim 39, characterized by guiding and supporting said labels from the bottom during the movement along said first positioning direction.

41) Method according to claim 40 characterized by supporting said labels by means of a flow of air.

42) Method according to one or more of claims 36 to 41 characterized in that said supply speed of the labels is adjusted to be equal or slightly lower than the speed with which the labels are moved along the first positioning direction. 43) Method according to claim '39, characterized in that said transfer element is activated by generating a vacuum inside one of its cavities to hold said labels on a lower surface in fluid connection with said cavity.

44) Method according to claim 43, characterized by activating a blow of air under pressure to facilitate¹ detachment of the labels from said transfer device and their gluing onto product.

45) A method to apply adhesive labels on a series of products, including the steps of:

> taking said labels individually by means of a grasping device;

> transferring said labels by means of said grasping device along a first path towards a transfer device;

> engaging said labels by means of said transfer device;

> transferring said labels by means of said transfer device to products.