EP2868399B1

EP2868399B1 - Process for manufacturing a transfer head for a container labeling machine

Info

Publication number: EP2868399B1
Application number: EP14191374.9A
Authority: EP
Inventors: Franco Cisamolo
Original assignee: CRM Engineering Srl
Current assignee: CRM Engineering Srl
Priority date: 2013-11-05
Filing date: 2014-10-31
Publication date: 2016-06-08
Anticipated expiration: 2034-10-31
Also published as: EP2868399A1; ITPD20130300A1

Description

Field of the art

The present invention refers to a process for manufacturing a transfer head for a container labeling machine.
The present process is inserted in the field of production of machines for bottling plants, or field of production of accessories for such machines.
In particular, the present invention is inserted in the field of labeling machines, which are intended to be employed in order to apply one or more labels on the outer surface of containers such as glass or plastic bottles.

State of the art

For some time, industrial labeling machines have been employed in the bottling field which are adapted to apply labels on liquid containers, such as bottles, in an automated manner.
In particular, labeling machines are known that employ cold adhesives for applying labels of non-winding type to containers; such labels are constituted by sheets of paper or plastic material of size such to only partially wind around the perimeter profile of the containers to which they are applied.
More in detail, the aforesaid labeling machines of known type comprise a rotary turret, which is adapted to receive from a first conveyor belt upstream the containers to which the labels are applied, to convey such containers to a labeling station, at which a label is applied to each container, and then to convey the containers (to which the labels have been applied) to a second conveyor belt adapted to convey the containers to a packaging machine downstream of the bottling line.
In addition, the labeling machines of known type comprise a first rotary carousel, bearing multiple transfer heads peripherally mounted thereon, which along their travel around the axis of the first carousel are adapted to pick up the labels from a storage, applying a layer of adhesive on such labels in order to allow gluing them to the containers.
In addition, the labeling machines of known type comprise a second rotary carousel, which bears multiple grip hooks peripherally mounted thereon, adapted to pick up the labels with the adhesive layer from the transfer heads of the first carousel and to apply such labels to the containers arranged on the rotary turret at the aforesaid labeling station.
More in detail, each transfer head of the aforesaid first carousel comprises a plate-like body with arched form, which is fixed to a vertical support rod, rotatably constrained to the first carousel itself and drivable by cam movement means to rotate around its axis.
In particular, the plate-like body of each transfer head is provided with a pick-up face with arched and convex form, directed towards the exterior of the first carousel, on which the adhesive layer to be applied to the labels is intended to be deposited. In addition, the labeling machine comprises a rotatable roller arranged in proximity of the first carousel, and metering means adapted to deposit, on the outer surface of such roller, the adhesive to be deposited on the pick-up face of the transfer heads of the first carousel.
In operation, the first carousel, driven to rotate around its rotation axis, bears each transfer head to adhere with its pick-up face on the outer surface of the aforesaid rotatable roller, in a manner such to transfer the adhesive layer from the roller to the pick-up face of the head itself.
In particular, when each transfer head is carried to the rotatable roller, the support rod of the transfer head is driven to rotate by the cam movement means of the labeling machine, in a manner such that the entire pick-up face of the transfer head adheres to the outer surface of the rotatable roller. The rotation speeds of the rotary carousels and the rotatable roller of the labeling machine are set in a manner such that the contact time between the pick-up face of each transfer head and the rotatable roller is sufficiently long to allow the adhesive layer to adhere to the pick-up face of the transfer head itself.
Subsequently, the first carousel bears each transfer head, on which the adhesive layer has been deposited, to the storage of the labels, which are packaged next to each other with their rear face directed towards the first carousel. In operation, the first carousel bears the pick-up face of each transfer head to adhere with the rear face of the first label of the packet of the storage, which in this manner is picked up from the storage itself, remaining attached to the adhesive layer deposited on the transfer head.
Subsequently, the first carousel bears the transfer head, which had picked up the label, to the second carousel, which with one of its grip hooks picks up the label from the transfer head, with the adhesive layer that remains attached to the rear face of the label in order to glue the latter to the corresponding container.
Also known in the state of the art are labeling machines in which the transfer heads of the first carousel are provided with a rubber covering fixed on the pick-up face of the plate-like body of the head itself.
The rubber covering exerts on the adhesive of the rotatable roller a greater friction force with respect to that exerted by the pick-up face of the plate-like body made of aluminum, and therefore the rubber covering is capable of picking up from the roller the adhesive layer also with the first carousel and the roller itself that operate at greater rotation speeds, therefore allowing the first carousel to supply a greater number of labels per unit of time and hence allowing the labeling machine to apply the labels to a greater number of containers.
The process of manufacturing transfer heads provided with rubber covering comprises a first molding step for obtaining the aluminum plate-like body by means of a melted aluminum casting in a first mold.
Then, a second molding step is provided for obtaining the rubber covering, by means of arranging a second mold in which the plate-like body is inserted and in which a melted rubber casting is then poured, in a manner such that the latter is deposited on the pick-up face of the plate-like body in order to achieve the rubber covering.
This process for manufacturing the transfer head is particularly costly, since it is necessary to arrange two molds, including the first for obtaining the aluminum plate-like body and the second for obtaining the rubber covering. Such drawback is particularly serious due to the fact that many label formats are diffused on the market, each of which requiring the arrangement of the labeling machine with a corresponding format of the transfer heads. It is therefore necessary to obtain two molds for producing each transfer head format, requiring a consequent high economic investment by the producer of the transfer heads themselves.
Also known is a further process for manufacturing transfer heads for labeling machines, which comprises a first step of obtaining a metal cylinder by means of a shell casting process, and then a step of rubberizing the cylinder in which, on the outer surface thereof, a layer of rubber is deposited.
Subsequently, a step is provided for processing in which the metal cylinder with the rubber layer is cut, by means of for example milling operations, in order to obtain the shape of the plate-like body corresponding to the format of the label to be applied.
Also the latter process has proven in practice to not lack drawbacks.
A first drawback is due to the fact that the metal cylinder obtained via casting has a rough outer surface which must be pre-processed before executing the rubberizing, therefore requiring the execution of further turning operations that involve relatively long production times for the transfer heads.
A further drawback is due to the fact that the production of the metal cylinder via casting is susceptible of leaving air bubbles in the molded cylinder, determining a defect thereof and which requires discarding the entire cylinder.
A further drawback is due to the fact that the plate-like body obtained by processing the metal cylinder cannot be fixed directly to the support rod of the first carousel of the labeling machine, and necessarily requires the manufacturing of a separate support body to be fixed to the plate-like body and provided with a connection in order to mount such support body on the corresponding support rod of the labeling machine, with consequent increase of the production costs.
The patent GB 629,078 describes a process of known type according to the preamble of claim 1 for building telegraph poles, which provides for manufacturing by means of extrusion two metal profiles with semicircular section and subsequently coupling such metal profiles together in a manner such to form an elongated tubular body.

Presentation of the invention

In this situation, the problem underlying the present invention is that of remedying the drawbacks manifested by the art known up to now, by providing a process for manufacturing a transfer head for a container labeling machine which allows producing a transfer head in a simple and inexpensive manner.
Further object of the present invention is to provide a process for manufacturing a transfer head for a container labeling machine which allows producing a mechanically strong transfer head.
Further object of the present invention is to provide a process for manufacturing a transfer head for a container labeling machine which allows producing a transfer head with limited weight.
Further object of the present invention is to provide a process for manufacturing a transfer head for a container labeling machine which allows producing transfer heads with different formats and sizes.

Brief description of the drawings

The technical characteristics of the invention, according to the aforesaid objects, can be clearly seen in the contents of the below-reported claims and the advantages thereof will be more evident in the following detailed description, made with reference to the enclosed drawings which represent a merely exemplifying and nonlimiting embodiment of the invention, in which:

figure 1 shows a schematized plan view of an embodiment of a labeling machine in which the transfer heads are intended to be employed which are obtained by means of the process, subject of the present invention;
figure 2 shows a perspective view of a rotatable carousel of the labeling machine illustrated in figure 1, such carousel bearing multiple aforesaid transfer heads mounted thereon;
figures 3a, 3b and 3c show one of the aforesaid transfer heads respectively in a front perspective view, in a rear perspective view and in a side view;
figures 4a and 4b show a rigid profile for manufacturing a transfer head by means of the process, subject of the present invention, respectively in a perspective view and in a side view;
figure 5 shows a side view of a tubular body obtained by means of a step of coupling the rigid profiles according to the process, subject of the present invention;
figures 6a and 6b respectively show a perspective view and a side view of the tubular body illustrated in figure 5, covered with a layer of polymer material according to a rubberizing step of the process, subject of the present invention.

Detailed description of a preferred embodiment

With reference to the set of drawings, reference number 1 indicates overall an embodiment of a transfer head for a labeling machine obtained by means of the process, subject of the present invention.
The transfer head 1 is intended to be employed in a labeling machine 2, which is conventionally inserted in a bottling plant downstream of a corking machine, for applying one or more labels on the outer surface of containers 3 such as, in particular, bottles. The containers 3 are transferred from one machine to another of the line by transport means, such as conveyor belts, star wheel conveyors, screws, etc.
In particular, the transfer head 1 is intended to be employed in labeling machines adapted to apply to the containers, preferably by means of cold adhesives, labels of non-winding type which are constituted by sheets of paper or plastic material of size such to only partially wind around the perimeter profile of the container to which they are applied.
With reference to the embodiment of figure 1, the labeling machine 2 comprises a first carousel 4, which is rotatably mounted on a support frame (not shown) abutted against the ground, and bears multiple aforesaid transfer heads 1 peripherally mounted thereon.
In operation, such first carousel 4 can be driven to rotate in order to convey each transfer head 1 between a first pick-up station 5, in which the transfer head 1 is adapted to receive a layer of adhesive glue, and a second pick-up station 6, in which the transfer head 1 applies such layer of adhesive glue on the back of a label 7 arranged in a storage 8, simultaneously picking it up from such storage 8, as described more in detail hereinbelow.
In addition, the labeling machine 2 comprises a second carousel 9, which is also rotatably mounted on the support frame of the machine 2 itself, and bears multiple grip hooks 10 peripherally mounted thereon, such hooks of per se known type for the man skilled in the art and adapted to pick up the labels 7 from the transfer heads 1 of the first carousel 4, at a delivery station 11 of the latter, and to apply such labels 7 to the containers 3.
The labeling machine 2 also comprises a third carousel 12, which is rotatably mounted on the support frame of the machine 2 itself, and is adapted to receive, from a first conveyor belt 13 upstream, the containers 3 to which the labels 7 are applied, and to convey such containers 3 around its rotation axis up to a labeling station 14, at which the grip hooks 10 of the second carousel 9 apply the corresponding labels 7 to the containers 3. Then, the third carousel 12 conveys the containers 3, to which the labels 7 have been applied, to a second conveyor belt 15 which conveys such containers 3, for example, to a packaging machine downstream of the bottling line.
With reference to the embodiment illustrated in figure 2, the first carousel 4 of the labeling machine 2 comprises a rotatable base 16 which bears multiple vertical support rods 17 peripherally mounted thereon, each of such rods bearing the corresponding transfer head 1 fixed thereon.
Each support rod 17 is rotatable constrained to the rotatable base 16, for example by means of bearings (not shown), and is drivable to rotate around its axis by movement means (preferably of cam type per se known to the man skilled in the art), in order to rotate the corresponding transfer head 1 at the first and second pick-up station 5 and 6, in order to respectively pick up the adhesive glue and the labels 7.
In particular, the first carousel 4 comprises a central column 18 fixed to the rotatable base 16 and bearing, fixed to its top, an upper disc 19 peripherally provided with multiple pivoting holes, in each of which the upper end of the corresponding support rod 17 is inserted.
In particular, each transfer head 1 is provided with a pick-up face 20, with arched and convex form, on which the adhesive glue layer is intended to be deposited at the first pick-up station 5, and which is subsequently intended to receive the label 7 from the storage 8 at the second pick-up station 6.
In particular, the labeling machine 2 comprises, at the first pick-up station 5, a rotatable roller 21 and metering means 22 (of known type) adapted to deposit, on the outer surface of such rotatable roller 21, the adhesive glue to be deposited on the pick-up face 20 of the transfer heads 1 of the first carousel 4.
In operation, the first carousel 4 bears the pick-up face 20 of each transfer head 1 to tangentially adhere with the outer surface of the aforesaid rotatable roller 21, in a manner such that the latter deposits the layer of adhesive glue on the pick-up face 20 itself.
In particular, when each transfer head 1 is carried to the rotatable roller 21, the support rod 17 of the transfer head 1 is driven to rotate by the movement means, in a manner such that the entire pick-up face 20 of the transfer head 1 adheres to the outer surface of the rotatable roller 21 on which the adhesive glue is deposited. Subsequently, the first carousel 4 bears each transfer head 1, on which the layer of adhesive glue has been deposited, to the storage 8 of the second pick-up station 6; in a per se known manner, such storage 8 comprises two parallel containment walls between which the labels 7 are arranged, packaged next to each other with their rear face directed towards the first carousel 4.
In operation, the first carousel 4 bears the pick-up face 20 of each transfer head 1 to adhere with the rear side of the first label 7 of the pack of labels 7 contained in the storage 8. In this manner, the aforesaid first label 7 is picked up from the storage 8, remaining attached to the layer of adhesive glue deposited on the pick-up face 20 of the transfer head 1.
Subsequently, the first carousel 4 bears the transfer head 1 (which picked up the label 7) to the second carousel 9, which, with one of its grip hooks 10, picks up the label 7 from the transfer head 1, with the layer of adhesive glue that remains attached to the rear side of the label 7 in order to glue the latter to the corresponding container 3 conveyed by the third carousel 12 to the labeling station 14.
With reference to the embodiment illustrated in figures 3a-c, the transfer head 1 comprises a rigid body 23 obtained via extrusion and intended to be fixed to the corresponding support rod 17 of the first carousel 4 of the labeling machine 2. Advantageously, the aforesaid rigid body 23 of the transfer head 1 is made of metal material, preferably aluminum.
In accordance with a different embodiment, the rigid body 32 is made of rigid plastic material, preferably comprising at least one technopolymer, in particular a loaded polymer, for example a carbon fiber loaded polymer, such as PEEK (polyetheretherketone), or a glass fiber loaded polymer.
The rigid body 23 of the transfer head 1 comprises an arched portion 24 provided with a front face 25 with convex form and with a rear face 26 directed in the direction opposite the front face 25, and also comprises a support portion 27 projectingly extended from the rear face 26 of the arched portion 24 and obtained in a single body with the arched portion 24 itself.
The support portion 27 of the rigid body 23 is intended to be fit to the corresponding support rod 17, drivable for rotating the corresponding transfer head 1 around a rotation axis Z, preferably vertical, in order to pick up the adhesive glue and the labels 7 as described above.
In addition, the transfer head 1 comprises a covering of polymer material 28 fixed on the front face 25 and preferably made of elastomeric material such as in particular rubber.
Advantageously, the polymer material 28 covering defines, on its external side, the pick-up face 20 of the corresponding transfer head 1, such pick-up face 20 intended to receive the layer of adhesive glue at the first pick-up station 5 of the first carousel 4 and the labels 7 at the second pick-up station 6 of the first carousel 4 itself.
In accordance with the embodiment illustrated in figures 3a-c, the front face 25 of the arched portion 24 of the rigid body 23 is extended around the rotation axis Z of the corresponding transfer head 1 between two lateral edges 24' of the arched portion 24, preferably with an arc of circumference profile.
Preferably, the support portion 27 of the rigid body 23 of each transfer head 1 comprises a fork-shaped retention clamp 29, and provided with two arms 29' substantially parallel to each other. In particular, such arms 29' are provided with corresponding ends constrained, directed towards the arched portion 24 and joined together by a connection portion 29", and with corresponding opposite free ends separated from each other.
More in detail, advantageously, the retention clamp 29 is provided with a through opening 30 obtained between the two arms 29' at the connection portion 29", aligned with the rotation axis Z of the transfer head 1 and in which the support rod 17 of the first carousel 4 is intended to be inserted. In addition, the retention clamp 29 is provided with a thinned groove 31 obtained between the two arms 29' at their free ends and communicating with the aforesaid through hole 30.
The retention clamp 29 also comprises a bolt 32 placed to connect to the two arms 29' at the thinned groove 31 in order to move the arms 29' themselves close together for the purpose of tightening them around the corresponding support rod 17 of the first carousel 4 of the labeling machine 2.
Advantageously, the arms 29' of the retention clamp 29 are provided at their free ends with enlarged portions 33, adapted to at least partially counter-balance the weight of the arched portion 24 of the rigid body 23 arranged in opposite position with respect to the rotation axis Z.
Advantageously, the rigid body 23 of the transfer head 1 is provided with one or more through holes 34 axially extended parallel to the rotation axis Z and in particular obtained in a through manner between an upper side 35 and a lower side 36 of the rigid body 23 itself.
Described below is a rigid profile 37 for manufacturing a transfer head, in particular of the type described above. Such rigid profile 37 is obtained via extrusion and is employable in the process for manufacturing a transfer head, subject of the present invention, and described in detail hereinbelow.
Advantageously, the aforesaid rigid profile 37 is made of metal material, preferably aluminum.
In accordance with a different embodiment, the rigid profile 37 is made of rigid plastic material, preferably comprising at least one technopolymer, in particular a loaded polymer, for example a carbon fiber loaded polymer, such as PEEK (polyetheretherketone), or a glass fiber loaded polymer.
With reference to the embodiment illustrated in figures 4a and 4b, the rigid profile 37 is extended along a longitudinal extension axis X and comprises an arched wall 38 extended around the longitudinal extension axis X between a first longitudinal coupling edge 39 and a second longitudinal coupling edge 40 countershaped with respect to each other.
Advantageously, the first and the second longitudinal coupling edge 39, 40 of the rigid profile 37 are shaped according to a male-female coupling profile, in a manner such that two or more rigid profiles 37 can be coupled together by means of such coupling edges in order to form a tubular body 46 (depicted in particular in the embodiment of figure 5), as will be described in detail hereinbelow with reference to the operating steps of the process for manufacturing a transfer head, subject of the present invention.
Preferably, the first longitudinal coupling edge 39 of each rigid profile 37 comprises a projecting appendage 39', extended parallel to the longitudinal extension axis X (in particular for the entire longitudinal extension of the rigid profile 37), and advantageously have rounded transverse section with an arc of circumference profile with angle at the center greater than 180°.
Preferably, the second longitudinal coupling edge 40 of each rigid profile 37 comprises two curved appendages 40' together delimiting a seat 40" that is countershaped with respect to the projecting appendage 39' of the first longitudinal coupling edge 39 and adapted to wind around the projecting appendage 39' itself in order to retain the latter within the seat 40".
Advantageously, in accordance with the embodiment illustrated in figures 4a and 4b, the arched wall 38 of the rigid profile 37 is provided with a convex face 41, preferably with arc of circumference profile (susceptible of partially defining an outer surface 47 of the aforesaid tubular body 46 when the rigid profiles 37 are coupled together), and with a concave face 42 directed in the direction opposite the convex face 41.
Each rigid profile 37 also preferably comprises at least one internal portion 43 projectingly extended from the aforesaid concave face 42 and obtained in a single body with the arched wall 38 of the rigid profile 37 itself.
As described in detail hereinbelow with reference to the process of manufacturing of the transfer head 1, the rigid body 23 of the transfer head 1 is obtained from the rigid profile 37, and in particular, the arched portion 24 of the rigid body 23 of the transfer head 1 is obtained from the arched wall 38 of the rigid profile 37, and the support portion 27 of the rigid body 23 of the transfer head 1 is obtained from the internal portion 43 of the rigid profile 37. In particular, the convex face 41 of the arched wall 38 of the rigid profile 37 is intended to define the front face 25 of the rigid body 23 of the transfer head 1.
Advantageously, each rigid profile 37 is provided with one or more longitudinal through holes 44, extended parallel to the longitudinal extension axis X of the rigid profile 37 itself, intended to correspond with the through holes 34 of the rigid body 23 of the transfer head 1 obtained from the rigid profile 37, and made for limiting the weight of the rigid body 23.
In addition, preferably, the rigid profile 37 comprises at least one radial separator 45 placed to separate between two of the aforesaid longitudinal holes 44, in order to ensure a suitable mechanical strength of the rigid body 23 of the transfer head 1 obtained from the rigid profile 37 itself.
Described in detail hereinbelow is an embodiment of the process, subject of the present invention, for manufacturing a transfer head for a labeling machine, in particular of the above-described type; the same references will be employed here for the sake of descriptive simplicity.
The present process comprises a step of manufacturing at least two rigid profiles 37 by means of an extrusion process, in which preferably one material in pasty state is poured into a recipient and then forced via compression to pass through the shaped cavity of a mold (or die) constituting a wall of the recipient itself, in order to obtain an extruded body at the outlet of the matrix. Such extruded body is then cooled in order to bring the material constituting it to the solid state.
Advantageously, in accordance with a particular embodiment, the material employed in the aforesaid extrusion process of the manufacturing step is a metal material and in particular aluminum.
In accordance with a different embodiment, the material employed in the aforesaid extrusion process of the manufacturing step is a plastic material preferably comprising at least one technopolymer, in particular a loaded polymer, for example a carbon fiber loaded polymer, such as PEEK (polyetheretherketone), or a glass fiber loaded polymer.
Preferably, after the cooling of the extruded body, the latter is transversely cut, obtaining the aforesaid rigid profiles 37 with the desired length.
Advantageously, in the aforesaid manufacturing step, the aforesaid longitudinal holes 44 of each rigid profile 37 are obtained, by means of in particular the arranging of a mandrel in the extrusion matrix at the respective longitudinal hole 44 to be obtained in the rigid profile 37 itself.
According to the present invention, the present process also comprises a step of coupling the two rigid profiles 37, in which the first longitudinal coupling edge 39 of each rigid profile 37 is constrained in a shape relationship with the second longitudinal coupling edge 40 of the other rigid profile 37, in a manner such that such rigid profiles 37 coupled together form a tubular body 46 provided with a substantially cylindrical outer surface 47 defined by the arched walls 38 of the rigid profiles 37 themselves.
More in detail, the rigid profiles 37 coupled together are arranged with the concave faces 42 of their arched walls 38 directed towards each other.
In particular, the outer surface 47 of the tubular body 46 is defined by the convex faces 41 of the rigid profiles 37.
Advantageously, in the aforesaid coupling step, the first longitudinal coupling edge 39 of each rigid profile 37 is fixed to the second longitudinal coupling edge 40 of the other rigid profile 37 by means of a male-female mechanical coupling. Advantageously, the step of coupling the rigid profiles 37 is obtained by inserting the projecting appendage 39' of the first longitudinal coupling edge of each rigid profile 37 in the seat 40" of the second longitudinal coupling edge 40 of the other rigid profile 37, by means of a relative sliding of the rigid profiles 37 parallel to the longitudinal extension axis X.
In accordance with the embodiment illustrated in figures 4a, 4b and 5, the tubular body 46 is obtained by means of the mutual coupling of two aforesaid rigid profiles 37, whose arched wall 38 advantageously has substantially semicircular form.
In accordance with a different non-illustrated embodiment, the tubular body is obtained with more than two rigid profiles, e.g. three or four profiles which will be provided with arched walls respectively extended for one third or for one fourth of circumference.
According to the invention, the present process for manufacturing a transfer head comprises a step of rubberizing the tubular body 46, in which at least one layer of polymer material 48 (in particular an elastomeric material, such as preferably rubber) is fixed on the outer surface 47 of the tubular body 46.
From such layer of polymer material 48, the polymer material covering 28 of the transfer head 1 is obtained, as described in detail hereinbelow.
Advantageously, the rubberizing step comprises a stage of fixing the layer of polymer material 48 on the outer surface 47 of the tubular body 46 by means of an adhesive material. In such fixing stage, the layer of polymer material 48, in the form of a flexible sheet, is wound around the outer surface 47 of the tubular body 46 covered with a layer of the aforesaid adhesive material.
Preferably, such fixing stage is obtained by means of a covering apparatus provided with a rotary head driven to bring the tubular body 46 in axial rotation, and with an extruder device which deposits, on the tubular body 46, a hot-extruded sheet of elastomeric material which, following the rotation of the tubular body 46 itself, comes to be wound around the outer surface 47 thereof.
The rubberizing step also comprises a stage of compression of the layer of polymer material 48 against the outer surface 47 of the tubular body 46, preferably by means of a mechanical rolling process, in order to expel the air possibly present between the layer of polymer material 48 and the outer surface 47 itself.
Preferably, such compression stage is obtained by means of a pressure roller of the aforesaid covering apparatus, such roller driven to press against the layer of polymer material 48 deposited on the tubular body 46 which is rotated by the rotary head of the apparatus itself.
Subsequently, the rubberizing step comprises a stage of treatment in a compression chamber of the tubular body 46 with the layer of polymer material 48, in order to eliminate possible residue air bubbles between the layer of polymer material 48 and the outer surface 47 of the tubular body 46.
Preferably, in the latter treatment stage, the tubular body 46 with the layer of polymer material 48 fixed thereon is placed within a compression chamber, in particular of an autoclave, whose internal pressure is brought in a controlled manner to a value of several bar (e.g. between about 5 and 30 bar) in order to further compress the layer of polymer material 48 against the outer surface 47 of the tubular body 46.
Preferably, the rubberizing step provides for a stage of vulcanisation of the layer of polymer material 48 fixed on the tubular body 46, obtained in particular in an autoclave, in order to increase the tensile strength of the polymer material as well as the chemical resistance of the latter to the substances of the adhesive glue intended to be deposited on the layer of polymer material 48 during the operation of the labeling machine 2.
According to the invention, the present process comprises, preferably after the rubberizing step, a processing step, in which at least the arched wall 38 of each rigid profile 37 (which forms the tubular body 46) and the layer of polymer material 48 (fixed on the outer surface 47 of the tubular body 46) are shaped, by means of removal, with a specific form corresponding to the format of the labels 7 to be applied to the containers 3.
In particular, from the processing of the arched wall 38 of the rigid profile 37, the arched portion 24 of the rigid body 23 of the transfer head 1 is obtained, and from the processing of the internal portion 43 of the rigid profile 37, the support portion 27 of the rigid body 23 of the transfer head 1 is obtained. In addition, from the processing of the layer of polymer material 48, the covering of polymer material 28 of the transfer head 1 is obtained.
Advantageously, the step of processing is obtained by means of milling, preferably employing removal tools with rotary movement, per se known to the man skilled in the art and for this reason not described in detail hereinbelow.
Advantageously, the step of processing provides for a first stage, in which the layer of polymer material 48 is cut, preferably by means of dry milling, and a second stage in which the rigid profile 37 is cut, preferably by means of milling with coolant.
In accordance with a different embodiment, the step of processing of the tubular body 46 is obtained, at least in several removal operations, by means of laser cutting.
The invention thus conceived therefore achieves the pre-established objects.
In particular, the process according to the invention, actuated by means of the use of multiple rigid profiles 37 obtained via extrusion and coupled together in order to obtain the tubular body 46, allows manufacturing the transfer heads 1 in a simple and inexpensive manner, in particular using molds for the extrusion with limited size.
In addition, the manufacturing of the rigid profile 37 by means of extrusion allows obtaining limited tolerances of the size of the convex face 41 of the rigid profile 37 (and hence of the outer surface 47 of the tubular body 46), preventing having to execute finishing operations of the outer surface 47 before the rubberizing step.
In addition, the manufacturing of the rigid profile 37 by means of extrusion allows obtaining the rigid body 23 of the transfer head 1 provided with the arched portion 24 and the support portion 27 obtained in a single body, without having to manufacture separate parts of the rigid body 23 that must be assembled together.

Claims

Process for manufacturing a structure, such process comprises the following operating steps:
- a step of manufacturing at least two rigid profiles (37) by means of an extrusion process,
each said rigid profile (37) extended along a longitudinal extension axis (X) and being provided with an arched wall (38) extended around said longitudinal extension axis (X) between a first longitudinal coupling edge (39) and a second longitudinal coupling edge (40) countershaped with respect to each other;

- a step of coupling at least two said rigid profiles (37), wherein the first longitudinal coupling edge (39) of each rigid profile (37) is constrained in a shape relationship with the second longitudinal coupling edge (40) of another said rigid profile (37),
said rigid profiles (37) coupled together forming a tubular body (46) provided with a substantially cylindrical outer surface (47) defined by the arched walls (38) of said rigid profiles (37);
characterized in that the process is used for manufacturing a transfer head for a container labeling machine and in that the process further comprises the following operating steps:
- a step of rubberizing said tubular body (46), wherein at least one layer of polymeric material (48) is fixed on the outer surface (47) of said tubular body (46);

- a step of processing, wherein at least the arched wall (38) of each said rigid profile (37) of said tubular body (46) and said polymeric material layer (48) are shaped, by means of removal, preferably milling or laser cutting, with a specific form corresponding to the format of labels (7) to be applied to containers (3).
Process according to claim number 1, characterized in that in said coupling step, the first longitudinal coupling edge (39) of each said rigid profile (37) is fixed to the second longitudinal coupling edge (40) of another said rigid profile (37) by means of a male-female mechanical coupling.
Process according to claim number 1 or 2, characterized in that said rubberizing step comprises:
- a stage of fixing said polymeric material layer (48) on the outer surface (47) of said tubular body (46) by means of least one adhesive material;

- a stage of compression of said polymeric material layer (48) against the outer surface (47) of said tubular body (46) by means of a mechanical rolling process;

- a stage of treatment in a compression chamber of said tubular body (46) with said polymeric material layer (48) fixed thereon.
Process according to one or more of the preceding claims, characterized in that said processing step comprises at least one milling operation of at least said arched wall (38) of said rigid profile (37) and said polymeric material layer (48).
Process according to one or more of the preceding claims, characterized in that said processing step comprises at least one laser cutting operation.