BR112013026085A2 - tire production process and installation - Google Patents

Abstract

PROCESS AND INSTALLATION FOR TIRE PRODUCTION. During tire construction, a crown structure (7) is constructed by the actions of: forming at least one belt layer (8a, 8b) on an auxiliary drum (22) to manufacture a belt structure (8) at least partially; turning axially opposed side flaps (10) of said at least one belt layer (8a, 8b) formed on the auxiliary drum (22); transferring the belt structure (8) from the auxiliary drum (22) to at least one service drum (31); forming a tread (9) by wrapping at least one continuous elongated element of elastomeric material in coils arranged mutually adjacent around the belt structure (8) carried by the service drum (31).

Description

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“PROCESS AND INSTALLATION FOR TIRE PRODUCTION” The present invention relates to a process and an installation to build tires for vehicle wheels.

More specifically, the invention is particularly concerned with the manufacture of ultra-high performance tires, above all for sports race cars.

A tire for vehicle wheels generally comprises a carcass structure including at least one carcass tarpaulin with end flaps respectively opposed in engagement with respective annular anchoring structures, integrated in the regions normally identified with the name "bands", defining the edges radially internal circumferential.

Associated with the carcass structure is a crown structure.

For the purposes of the present specification and the following claims, "crown structure" of a tire means at least one belt or breaker structure with one or more layers of belt placed in radially overlapping relation to each other and with the canvas carcass, with textile or metallic reinforcement cords in a crossed orientation and / or substantially parallel to the direction of the circumferential extension of the tire.

More preferably, the crown structure comprises a belt structure with at least one belt layer and a tread made of elastomeric material applied in a radially external position on the belt structure.

Furthermore, the respective sides of elastomeric material are applied in an axially external position on the lateral surfaces of the carcass structure, each one extending from one of the lateral edges of the tread until close to the respective annular anchoring structure in the beads.

In “tubeless” type tires, an airtight coating layer usually referred to as “inner lining cloth” covers the inner surfaces of the tire.

DE 19532352 reveals a belt structure in which each

2/30 layer of the strap is pre-folded into a desired shape and is applied to the carcass in the already folded state.

The belt bending is achieved in the strip material in a flat shape.

WO 2009-081220, by the same Applicant, provides a construction installation comprising a carcass structure construction line and a crown structure construction line.

The crown structure construction line comprises a first construction drum on which an annular assembly comprising a first belt layer and a second radially external belt layer for the first belt layer is constructed.

The crown structure construction line further comprises an auxiliary drum on which the portions of the opposite end of the first belt layer are turned upwards so as to obtain at least a partial overlap of the end portions of the first belt layer in said at least a second layer of brace.

It is thought that it is particularly suitable to return the ends of the belt layers for performance purposes.

In fact, the return of the axially opposite flaps of a belt layer over the belt layers radially external to them gives the tire more reactivity and quicker response to the tire during the curve-making step.

Referring particularly to ultra-high performance tires, above all if intended for race cars that impose difficult handling conditions, it is thought that it is appropriate to manufacture the layer or layers of belt starting from articles manufactured in the form of a strip with textile-type reinforcement cords, whose axially opposite side edges are looped to cover at least partially the outermost belt layer.

Also, it was noticed that, in the manufacture of some models of

3/30 tire, it is preferable that the axially opposite flaps of one or more of the radially innermost belt layers are looped in the outermost radial layer or belt layers, in order to prevent the free ends of the reinforcement cords from interfering mechanically in the carcass structure, thereby causing cracks that would tend to propagate and damage the tire structure.

It has been found the possibility to manufacture the belt structure by means of a process in which an annular assembly comprising a first radially internal belt layer and at least one radially external belt layer is formed in a first drum.

Axially opposite end portions of the first belt layer would then be looped over said at least a second belt layer, so as to cause at least partially overlapping of the end portions of the first belt layer on said at least one belt layer radially external.

Furthermore, it is believed that in the manufacture of tires for racing and / or ultra-high performance sports tires, the manufacture of the tread by spiral is particularly advantageous, that is, by rolling a continuous elongated element of raw elastomeric material so as to form turns respectively arranged adjacent to each other around the belt structure until defining the tread consisting of one or more layers of thickness and profile in the desired cross section.

Also, it was noticed that the turn performed in the fabrication of the belt and spiral structure performed in the formation of the tread typically requires excessively long manufacturing times; these times, added together, reduce productivity.

Furthermore, the use of relatively complicated and large equipment is necessary for these operations, whose equipment can hardly be integrated into the same

4/30 production unit.

In this context, the applicant felt the need to reconcile the requirement to carry out particular operations in such a way that the repeated turning and spiraling required in the manufacture of the crown structure with the purpose of achieving excellent quality standards and maximum reproducibility of results in the product final, with the requirement of obtaining high exploitation of the equipment and efficient limitation of processing downtime, in order to benefit from production efficiency.

It was realized that, if provision is made for the simultaneous execution of different process actions during the manufacture of the crown structures intended for the respective tires in production, it is possible to optimize the time required for the execution of each of the said process actions, in harmony with the time required to build the carcass structure and coupling it to the crown structure itself.

Therefore, it was observed that, providing in the construction area of the crown structure, operations back to one or more of the belt layers and spiral operations to the tread during which said belt layers are transferred to a service drum where the construction of said tread continues, the processing of different crown structures seems to be divided, to benefit from the qualitative resources of the final product, without impairing productivity.

In more detail according to a first aspect, the invention relates to a process for producing tires, comprising: - building a carcass structure; - build a crown structure; - couple the crown structure with the carcass structure; wherein the construction of the crown structure comprises:

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- forming at least one belt layer on an auxiliary drum to manufacture at least partially a belt structure; - turning the side flaps axially opposed to said at least one belt structure on the auxiliary drum; 5 - transfer the belt structure of the auxiliary drum to at least one service drum; - forming a tread by wrapping at least one continuous elongated element of elastomeric material, by forming turns arranged axially side by side around the belt structure carried by the service drum.

Thus, it is thought that it is possible to reconcile the requirement to carry out the particular operations required in the manufacture of the crown structure in order to achieve excellent qualitative standards and maximum reproducibility of results in the final product, with the requirement to obtain high exploitation of the equipment and reduction efficient downtime during processing to benefit from production efficiency.

In particular, performing back operations on at least one of the belt layers and spiraling operations to obtain the tread allows for excellent qualitative features in the final product, particularly appreciated in tires for ultra-high performance sports racing in tire, without compromising productivity.

In a second aspect, the invention relates to a tire production facility, comprising: - a construction line for carcass structures; - a construction line for crown structures; - an assembly site in which each crown structure is coupled with one of the carcass structures; wherein said construction line for crown structures

6/30 comprises: - at least one auxiliary drum; - at least one service drum; - a device for forming a belt structure on said auxiliary drum 5, said devices comprising elements for forming at least one belt layer and elements for returning axially opposite side flaps of said at least one belt layer on the auxiliary drum; transfer devices for transferring a belt structure at least partially formed in the auxiliary drum to said at least one service drum; - device for forming a tread by wrapping at least one continuous elongated element of elastomeric material, through the formation of turns arranged in mutual side-by-side around the belt structure carried by the service drum.

The present invention, according to at least one of the aspects presented, can have one or more of the preferred features described below.

The action of forming, in said auxiliary drum, the belt structure of at least one first tire that is being processed can be at least carried out simultaneously with the action of forming the tread of at least one second tire that is being processed, at least one service drum is not said.

The action of coupling the crown structure to the carcass structure is preferably carried out at the same operating rate followed by the actions of forming the tread and forming the belt structure.

For the purposes of this specification, it is understood that the term "operating fee" indicating the inverse of the time between the start of a processing operation at a given location, the location of

7/30 assembly, for example, or another job site, and the start of a new processing operation aimed at building an immediately following tire, at the same job site.

For example, if the said time is 60 s, the operating rate will be 1/60 Hz. 5 The construction of the crown structures belonging to the respective tires being processed can be carried out simultaneously on the respective service drums.

Thus, it is possible to further reduce the cycle time, for example, by performing the targeted spiral to complete the belt structure and / or obtain the tread, thereby further increasing the flexibility of process operation.

In particular, it is possible to increase the precision in the realization of the spiral, limiting the linear deposition speed of the continuous elongated element, for example, in order to guarantee more geometric precision in the deposition and eliminating the risk of inclusion of air bubbles between the formed turns. with the continuous elongated element, without compromising productivity.

The action of forming the tread of the first tire being processed and the action of forming the tread of the second tire being processed are at least partially performed simultaneously with the fabrication of the belt structure of an additional tire that is being processed. being processed.

A new belt structure will already be available to manufacture the tread, as soon as processing for tread fabrication on the previous tire has been completed.

During formation of the tread, said at least one service drum is preferably driven in rotation and moved by at least one robotic arm in front of a dispensing element that supplies said continuous elongated element of elastomeric material.

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The movement of the service drum by a robotic arm, preferably of the anthropomorphic type, simplifies the spiraling operation.

The positioning and support action of said at least one service drum can also be performed by at least one robotized arm 5 during the action of transferring the belt structure from the auxiliary drum to said at least one service drum.

The high operational flexibility typical of the robotic arm, preferably anthropomorphic, reduces operational restrictions in the positioning of different workplaces.

In fact, the transfer of the service drum for interaction with other workplaces, before and / or after the completion of the spiral, can be achieved quickly and with high flexibility of geometric positioning.

Furthermore, the same robotic arm used to support the service drum during spiraling operations can be advantageously employed for transfer operations.

Preferably, the action of forming said at least one belt layer comprises: - circumferentially wrapping at least one article made in the form of a strip of elastomeric material including textile cords, around the auxiliary drum; - join the opposite ends of the manufactured article together in the form of a strip.

The use of a manufactured or semi-finished article like this guarantees ideal structural homogeneity of the belt layers, which is particularly appreciated in tires designed to provide very high performances in sports competitions.

The construction of the crown structure may additionally comprise the action of circumferentially rolling up a pair of

9/30 tape-like reinforcement, each being radially superimposed on an end edge of one of the side flaps with turns of said at least one layer of strap.

The looped end edges are thus conveniently protected, unwanted contact with other parts of the tire during use being avoided.

The construction of the crown structure may additionally comprise the action of circumferentially winding at least one reinforcement element of elastomeric material longitudinally incorporating at least one continuous cord in the form of turns arranged in axial side-to-side around said at least one layer of strap.

Thus, an additional belt layer is formed, which is usually referred to as a “zero degree layer” in accordance with the orientation of the reinforcement cords relative to a circumferential direction, which is used to maintain a desired cross-sectional profile of the tire, even under the effect of high centrifugal forces triggered during use.

The winding of said reinforcement element can be carried out in the belt structure transferred to the service drum.

It is thus possible to balance the working time for operations carried out on the auxiliary drum and the service drum, respectively.

Furthermore, the formation of the zero degree layer on the service drum allows the belt structure to be modeled, if necessary according to a curvilinear cross sectional profile using a service drum with an external surface with a convex profile.

Preferably, the action of transferring the belt structure from the auxiliary drum to said at least one service drum comprises the actions of:

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- removing the belt structure from the auxiliary drum by a first transfer element; - engage the belt structure on the service drum by the first transfer element. 5 The removal of the belt structure from the auxiliary drum comprises the actions of: - axially inserting the auxiliary drum that carries the belt structure in the first transfer element; - engage the belt structure with the first transfer element; - contract the auxiliary drum radially to disengage it from the belt structure; - transfer the auxiliary drum in an axial direction relative to the first transfer element to remove the auxiliary drum from the belt structure.

Preferably, the action of engaging the belt structure in the service drum comprises: - inserting the service drum axially in the first transfer element that carries the belt structure; - radially expand the service drum in order to engage it with the belt structure.

This way it is possible to balance the working time for the operations carried out on the auxiliary drum and the service drum, respectively.

In addition, the formation of the zero degree layer on the service drum allows the belt structure to be modeled, if necessary according to a curvilinear cross-sectional profile using a service drum with an external convex profile surface.

Preferably, the action of transferring the belt structure from the

Auxiliary drum for said at least one service drum comprises the actions of: - removing the belt structure of the auxiliary drum by a first transfer element; 5 - engage the belt structure on the service drum by the first transfer element.

The removal of the belt structure from the auxiliary drum comprises the actions of: - axially inserting the auxiliary drum that carries the belt structure in the first transfer element; - engage the belt structure with the first transfer element; - transfer the auxiliary drum in an axial direction relative to the first transfer element to remove the auxiliary drum from the belt structure.

Preferably, the action of engaging the belt structure in the service drum comprises: - inserting the service drum axially in the first transfer element that carries the belt structure; - radially expand the service drum in order to engage it with the strap structure; - disengage the first transfer element from the belt structure; - axially transfer the service drum that carries the belt structure to remove the service drum that carries the belt structure from the first transfer element.

Preferably, the first transfer element maintains a stationary position during the transfer of the belt structure.

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The first transfer element can therefore have a very simple structure, the axial movements being completely carried out by the auxiliary drum and the service drum.

In this regard, it is possible to use the axial mobility already required by the service drum for the formation of the tread, and the auxiliary drum for its movement between different workplaces provided for manufacturing the belt structure.

The coupling of the crown structure to the carcass structure preferably comprises the action of transferring the crown structure from the service drum to a primary drum which carries the carcass structure.

Preferably, the action of transferring the crown structure from the service drum to the primary drum comprises the actions of: - removing the crown structure from the service drum by a second transfer element; - engage the crown structures on the primary drum using the second transfer element.

The action of positioning and supporting the service drum by a robotic arm can also be performed during the action of transferring the crown structure from the service drum to the primary drum.

The same robotic arm, preferably anthropomorphic, used to support the service drum during spiraling operations can be advantageously used for the transfer operations from the crown structure to the second transfer element.

The action of removing the crown structure from the service drum preferably comprises: - axially inserting the service drum carrying the crown structure in the second transfer element;

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- engaging the crown structure with the second transfer element; - contract the service drum radially in order to disengage it from the crown structure. 5 If the axial movements are based on the service drum, it is possible to simplify the structure and operating volume of the second transfer element.

In this regard, the axial mobility already required from the service drum to distribute the continuous elongated element during formation of the tread can be used.

Preferably, the belt structure forming device, and the tread forming devices, operate simultaneously with each other, in the belt structure and the tread, respectively, of the respective tires being processed.

Belt structure forming devices and tread forming devices can operate simultaneously with the manufacture of at least one carcass structure in the carcass structure construction line.

Preferably, the crown structure construction line comprises: - a first working area in which said at least one auxiliary drum is operatively arranged; - a second work area in which said at least one service drum is operationally arranged; and - a first transfer location in which said transfer devices operate.

The banding devices may comprise elements for forming a first portion of the tread and elements

14/30 to form a second portion of the tread which operate simultaneously with said belt forming devices.

The use of at least one robotic arm is preferably provided to rotate it and move said at least one service drum in front of at least one dispensing element of said at least one continuous elongated element of elastomeric material.

Additionally, or alternatively, at least one robotic arm can be provided to support the service drum during actuation of the transfer devices.

The elements for forming at least one belt layer preferably comprise a feeding unit for supplying at least one article manufactured in the form of a strip of elastomeric material comprising textile cords in a first workplace designed to wrap said at least one article manufactured around the auxiliary drum.

The belt forming devices may additionally comprise a feeding unit for supplying a pair of ribbon-like reinforcement inserts at a second workplace designed to wrap said ribbon-like reinforcement inserts around said at least one belt layer.

The belt forming devices preferably comprise a carriage that carries the auxiliary and movable drum to selectively position said auxiliary drum in front of at least one of the first work site and the second work site.

Preferably, the means of transport is movable in parallel to a geometric axis of rotation of the auxiliary drum.

The elements for reversing the axially opposite side flaps of said at least one layer of strap are preferably at least

15/30 partially integrated in said auxiliary drum.

The construction line of the crown structure can additionally comprise winding devices for circumferentially winding at least one reinforcement element of elastomeric material in turns 5 axially side by side around said at least one strap layer, the reinforcement element of which incorporates longitudinally at least one continuous cordon.

The winding devices operate on the belt structure carried by the service drum at a third job site.

More particularly, said at least one service drum can be braked with at least a third and a fourth workplace.

In a possible embodiment, provision is made for at least one of the first service drum and a second service drum to operate simultaneously in each of said third and fourth workplaces.

The service drum may have an external surface modeled in a curved cross sectional profile.

Preferably, the transfer devices comprise a first transfer element to be positioned alternately around the auxiliary drum and around the service drum.

The first transfer element preferably comprises radially movable elements to selectively engage and release the belt structure.

The auxiliary drum is preferably movable along its geometric axis of rotation to be coaxially engaged with the first transfer element.

The auxiliary drum can be radially contractile to disengage the belt structure engaged by the first transfer element.

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The service drum can be movable along its geometric axis of rotation to be coaxially engaged with the first transfer element.

The service drum can be radially expandable to engage the belt structure carried by the first transfer element.

The first transfer member is preferably attached substantially to said crown structure construction line.

The construction line of the carcass structure can comprise a primary drum with axially movable halves next to each other to determine the radial expansion of the carcass structure.

Preferably, provision is made for a second transfer location including at least a second transfer element which can alternatively be positioned around the service drum and around a primary drum operating on the construction line of the carcass structure.

The service drum is preferably movable along its axis of rotation to be coaxially engaged with the second transfer element.

The second transfer element is preferably movable along a geometric axis of rotation of the primary drum to position the crown structure coaxially around the primary drum.

The service drum can be radially contractile to disengage the crown structure in engagement with the second transfer member.

Preferably, the robotic arm is an anthropomorphic robotic arm.

Additional features and benefits will become more apparent from

17/30 of the detailed description of a preferred, but not exclusive, embodiment of a process and an installation for constructing tires according to the present invention.

This description will be presented below with reference to the 5 attached drawings, given as a non-limiting example, in which: Figure 1 shows diagrammatically a top view of an installation for building tires carried out according to a preferred example of the present invention; Figure 2 shows diagrammatically a top view of an installation for constructing a tire carried out according to a possible preferred variant of the present invention; Figure 3 shows a cross section of a tire obtainable according to the present invention.

With reference to the aforementioned figures, an installation to build tire for vehicle wheels designed to carry out a process according to the present invention has been identified in general as the reference number 1. Installation 1 is designed to construct tire 2 (figure 3) essentially comprising a carcass structure 2a with at least one or several carcass linings 3. For the sake of simplification, reference will be made hereinafter by way of example only to the presence of only one carcass tarpaulin 3, it being understood that, if necessary, two or more carcass linings will be provided, depending on requirements.

A layer of air-tight elastomeric material or the so-called “inner lining” 4 can be applied internally to the carcass canvas 3. Two annular anchoring structures 5, each including a so-called bead core 5a carrying an elastomeric load 5b in radially external position, are in engagement with the

18/30 respective end flaps 3a of the carcass tarpaulin 3. The annular anchoring structures 5 are integrated in the vicinity of regions normally identified with the name of “beads” 6, where the engagement between the tire 2 and a respective rim usually occurs 5 assembly.

A crown structure 7 is applied circumferentially around the carcass structure 3. The crown structure 7 comprises a belt structure 8 with one or more layers of belt 8a, 8b and, preferably, a tread 9 circumferentially overlapping the structure of band 8. More particularly, in the example shown, provision is made for a first radially inner band layer 8a, and at least a second radially outer band layer 8b.

At least one belt layer, in the example shown the first belt layer 8a, will have axially opposite side flaps 10 facing in a radially outer position in the second radially outermost belt layer 8b.

In the absence of the radially outer belt layer or layers 8b, the side flaps 10 of the first belt layer 8a can be turned in the first belt layer position.

The belt structure 8 can additionally comprise a pair of ribbon-like reinforcement inserts 8c, each radially overlapping an end edge 10a of one of the looped side flaps10. In addition, at least one so-called zero grade 11 layer can be radially superimposed on the strap layers 8a, 8b and possible tape-like reinforcement inserts 8c to give the strap structure 8 a predetermined strength for circumferential and radial extensibility.

Two sides 12, each extending from the corresponding bead 6 to a corresponding side edge of the tread

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9, are applied in laterally opposite positions on the carcass canvas 3. Figure 1 preferably comprises a carcass structure construction line 13, where carcass structures 2a of the tires being processed are formed. 5 The crown structures 7 are built on a crown structure construction line, identified as a whole by 14 in figure 1. In an assembly location 15, the coupling of each frame structure 2a with a respective crown structure 7 is performed.

More particularly, in the example shown, the assembly site 15 is operationally integrated into the construction line of the frame structure 13. According to an embodiment shown in figures 1 and 2, the construction line of the frame structure 13 comprises at least one primary drum 17, on which the carcass structure 2a of tire 2 is constructed.

The primary drum 17 can be operationally supported by a mandrel 18 or another device that allows it, if necessary, to be rotated and / or moved properly between one or more work units 19 during application of the components of the frame structure 2a .

More specifically, the primary drum 17 is adapted to first receive the inner liner 4, if any; and subsequently the carcass tarpaulin 3, so as to form a cylindrical jacket on the axially opposite side flaps 3a from which the annular anchoring structures 5 will subsequently be assembled.

Then, the side flaps 3a of the carcass tarpaulin 3 around the annular anchoring structures 5 can be carried out.

The application of at least a portion of the sides 12 to the primary drum 17 can also be provided, as well as the application of at least one abrasion resistance element, depending on the construction process.

In the form of manufacture described above, primary drum 17 is

20/30 of the type adapted to carry out the construction of the tire 2 following the so-called “single-stage process”, in which the coupling between the crown structure 7 and the frame structure 2a does not require transfer of the frame structure 2a from said primary drum 17 in which it was constructed for another drum 5, since the primary drum halves 17 which are axially movable towards each other are provided to determine radial expansion of the housing structure 2a, to couple the latter with the housing structure crown 7. In a preferred embodiment the primary drum 17 can be a second stage drum or a so-called “modeling drum” in which a carcass structure 2a built somewhere else, for example, although not necessarily on said line of the carcass structure, is initially engaged, while subsequently a corresponding belt structure 7 is brought to an external position radially to said end of the drum and due centralized body structure already present 2a.

This type of primary drum 17 is also provided with halves that are movable axially towards each other to determine the radial expansion of the frame structure 2a to couple it with the crown structure 7. In both cases described, said location of assembly 15 is therefore coincident with the location of the primary drum 17. In the construction line of the crown structure 14, at least a first working area 20 and at least a second working area 21 can preferably be identified.

In the first working area 20, belt structure forming devices 26 operate to construct a belt structure 8 or at least a first part thereof, on at least one auxiliary drum 22. The auxiliary drum 22 can be rotationally supported by a means of transport 23 which is mobile preferably in parallel with a

21/30 geometric axis of rotation X of the auxiliary drum; to selectively position it in front of at least a first workplace 24 and a second workplace 25 spaced from each other.

The devices for forming the belt structure 26 5 preferably comprise elements designed to form at least a first layer of belt 8a, by means of a first feeding unit 27, for example, operating in the first working place 24 to dispense at least one first article manufactured in the form of a strip of elastomeric material including textile cords arranged parallel adjacent to each other and oriented according to a predetermined angle, preferably included between about 30 ° and about 60 °, in relation to the longitudinal extent of the article itself.

The first manufactured article dispensed by the first feed unit 27 is applied around the auxiliary drum 22, activated in rotation so as to form the first layer of belt 8a wound in a complete loop around the auxiliary drum 22 itself. At the end of the winding , the first manufactured article is cut transversely in the vicinity of the auxiliary drum 22 and the ends of the first belt layer 8a thus formed are mutually joined end to end.

A second feed unit 28 can also be provided for dispensing a second article manufactured in the form of a strip of elastomeric material preferably with a width less than or equal to that of the first article manufactured.

The second manufactured article may comprise textile or metallic cords arranged parallel adjacent to each other and oriented according to a predetermined angle, preferably included between about 30 o and about 60 o in relation to the longitudinal extent of the manufactured article, and with relative cross orientation to the cords of the first article manufactured.

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The second manufactured article is preferably applied around the first belt layer 8a in the same manner as said first belt layer, so as to form the second belt layer 8b wound in a complete loop around the auxiliary drum 22. At the end of the winding, the second manufactured article is cut transversely in the vicinity of the auxiliary drum 22, and the ends of the second belt layer 8b thus formed are mutually joined end to end.

The second feed unit 28 can be operationally installed at exactly the first job site 24 that carries the first feed unit 27, or at a separate job site.

In the aforementioned case, the intervention of the second feed unit 28 will take place after the actuation of the means of transport 23, to remove the auxiliary drum 22 from the first work site and take it to the place that carries the second feed unit 28. When the deposition of the belt layers 8a, 8b has been completed, the axially opposite side flaps 10 of said at least one first belt layer 8a, preferably projecting axially beyond the respective end edges of the second belt layer 8b, are with turns in such a way that they are radially overlapped externally to the second layer of strap itself.

This operation can be carried out by suitable turn elements not described or shown in detail, since they are obtainable in a manner known to you, with the help, for example, of inflatable and / or properly deformable bags by means of the command of thrust elements mechanically partially or completely integrated in the auxiliary drum 22 itself. The lap operation can be performed after moving the means of transport 23 to position the auxiliary drum 22 in a turn location 29 laterally spaced from the first work location

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24 in which the return of the first strap layer 8a and / or the second strap layer 8b occurs, in order to avoid mechanical interference between the elements intended to form the strap layer or layers 8a, 8b and the aforementioned back elements. 5 In the first working area 20, a third feed unit 30 can also be operationally arranged to supply the pair of ribbon-like reinforcement inserts 8c, each made in the form of a strip of elastomeric material with axial size preferably less than half the axial size of the strap layers 8a, 8b when the loop has been completed.

Each ribbon-like reinforcement insert 8c preferably incorporates textile cords, nylon cords, for example, extending longitudinally.

The third feed unit 30 preferably operates at said second workplace 25 designed to wrap ribbon-like reinforcement inserts 8c around the previously formed belt layer or layers 8a, 8b.

The second work site is reached by the auxiliary drum 22 after movement of the means of transport 23, after the return step.

The ribbon-like reinforcement inserts 8c can be distributed simultaneously close to the side flaps with turns 10 of the layer or belt layers 8a, 8b, while the auxiliary drum 22 is being driven in rotation to determine the winding of said inserts in a complete rotation.

At the end of the winding, each of the ribbon-like reinforcement inserts 8c is transverse cut in the vicinity of the auxiliary drum 22 and joined end to end at respective ends.

When the process in the first working area 20 has been completed, construction of the crown structure 7 continues in the second working area 21, interlocked with at least one service drum 31, preferably connected to a robotic arm 32, preferably of the anthropomorphic type .

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For this purpose, the auxiliary drum 22 is preferably driven, by the axial displacement of the means of transport 23, for example, to a first transfer place 33 operationally disposed between the first working area 20 and the second working area 21. In the first 5 transfer location 33, device 34 operate to transfer the belt structure 8 from the auxiliary drum 22 to the service drum 31. In a preferred embodiment, these transfer devices 34 comprise at least one first transfer element 34a which can be alternately positioned around the auxiliary drum 22 and the service drum 31. Preferably, the first transfer element 34a is substantially fixed to said crown structure construction line 14 and is adapted to be alternately engaged by the auxiliary drum 22 and the service drum service 31. The auxiliary drum 22 is in fact movable along its geometric axis of rotation X by means of the transport means rte 23, to be coaxially inserted into the first transfer element 34a.

When the auxiliary drum 22 is coaxially inserted, preferably in an axially centralized position, in the first transfer element 34a, radially mobile elements (not shown) operationally associated with said drum and made in the form of circumferentially consecutive circular sectors, for example, perform engaging the belt structure 8 or its first part formed in the auxiliary drum 22. The auxiliary drum 22, consisting of radially contractile sectors (not shown) is radially contracted in order to disengage the belt structure 8. By a backward movement of the means of transport 23, the

25/30 auxiliary drum 22 is axially translated in relation to the first transfer element 34a and consequently removed from the belt structure 8 which is retained by the first transfer element 34a by means of the radially movable elements in a radially contracted position. 5 The service drum 31 in turn is adapted to be moved along its axis of rotation X1 by means of the robot arm 32, to be coaxially inserted into the first transfer element 34a which carries the belt structure 8. The drum service 31 comprising radially mobile sectors (not shown), for example, can be radially expanded to engage the belt structure 8. After expansion of the service drum 31, the radially mobile elements of the first transfer element 34a are radially separate from the belt structure 8 that will remain in engagement with the service drum 31. If necessary, the service drum 31, at least in radially expanded condition, can show an outer surface with a curvilinear cross sectional profile, in order to impose a desired conformation on the belt structure 8 engaged by the service drum

31. By means of the robotic arm 32, the service drum 31 is then moved axially to be removed from the first transfer element 34a together with the belt structure 8. The robotic arm 32, of the type with six or more axes of movement, by For example, it is able to support, rotate and conveniently move the service drum 31 in the second working area 21 to create the tread 9 and, if necessary, at least a second part of the belt structure 8.

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This second part of the belt structure 8 can, for example, comprise the aforementioned zero degree layer 11 which, as an indication only, extends at least 80% of the axial extension of the belt layer or layers 8a, 8b.

Grade 11 zero layer is applicable additionally 5 or alternatively to ribbon-like reinforcement inserts 8c in the first work area 20, by means of winding devices 35 operating in a third work place 36, preferably installed in the second work area 21. The grade 11 zero layer is obtained by circumferentially wrapping at least one reinforcement element of elastomeric material longitudinally incorporating one or more continuous strands in the form of turns arranged in tiled relationship around the layer or layers of strap 8a, 8b.

The reinforcement element can be supplied by the winding devices 35 in the service drum 31, while it is being operated in rotation and conveniently moved by the robot arm 32 in front of the winding devices 35. When the formation of the grade 11 zero layer, if there is, has been completed, the robotic arm 32 places the service drum 31 close to at least a fourth workplace 37, in which tread forming devices 38 operate, which, for example, comprise at least one extruder or another element suitable for carrying out controlled supply of a continuous elongated element of elastomeric material.

The auxiliary drum 22 is driven in rotation and suitably moved by the robotic arm 32 in order to determine the deposition of the continuous elongated element in mutually adjacent turns around the belt structure 8 carried by the service drum 31, until the formation of the tread 9 with the desired conformation and thickness have been completed.

27/30

In case of need, as shown by way of example in figure 2, the tread forming devices 38 may comprise two or more extruders 38a, 38b or different dispensing elements, possibly arranged in respectively 5 different workplaces, of in order to form at least a first and a second portion of the tread 9, respectively, and / or other tire components, using different compositional materials.

The use of at least a first service drum 31a and a second service drum 31b, similar or different from each other, can also be provided, each locked with a respective robotic arm, preferably anthropomorphic, 32a, 32b, to perform construction simultaneous use of crown structures 7 belonging to different tires in the second working area.

More particularly, the formation of the first tread portion 9 on the first service drum 31a and the second tread portion 9 on the second service drum 31b can be carried out simultaneously.

Additionally, or alternatively, the tread formation 9 of a first and a second tire being processed can be carried out simultaneously, on the first service drum 31a and the second service drum 31b, respectively.

In addition, or alternatively, as shown by way of example in figure 2, the formation of the tread 9 on the first service drum 31a and the second part of the belt structure 8, that is, the grade 11 zero layer, on the second drum service 31b can be performed simultaneously.

When the manufacturing of the tread 9 has been completed, the respective service drum 31, 31a, 31b can be placed

28/30 in engagement with a second transfer location 16, with the help of the robot arm 32. The second transfer location 16 preferably comprises at least one second transfer element 39 which can be alternately positioned around the transfer drum. service 31 and around said primary drum 17, operating on the construction line of the frame structure 13. More particularly, the service drum 31 carrying the crown structure 7 is adapted to be moved along its geometric axis of rotation X1, by command of the robotic arm 31, to be coaxially mounted on the second transfer element 39. The second transfer element 39, for example, comprises radially mobile elements (not shown) which are adapted to be radially contracted in order to engage the crown structure 7 carried by the service drum 31 in order to remove it from there.

After contraction of the radially movable elements of the second transfer element 39, radial contraction of the service drum 31 is determined.

The service drum 31 consequently disengages the crown structure 8 which remains in engagement with the second transfer element 39. At this point, the service drum 31 can be axially removed from the second transfer element 39, by means of the action of the robotic arm 32 and / or after radial movement of the second transfer element itself.

In fact, the second transfer element 39 is preferably movable along a geometric axis of rotation X2 of the primary drum 17, as shown in figures 1 and 2, in order to position the crown structure 7 coaxially around the primary drum 17 After mutual approach of the primary drum halves 17,

29/30 the coupling of the crown structure 7 with the housing structure 2a is determined. After the radially movable elements integrated in the second transfer element 39 are separated, said transfer element 5 can be axially disengaged from the crown structure 7 which will remain in engagement with the housing structure 2a in the primary drum

17. After possible additional processing operations have been carried out with the purpose of improving the adhesion of the anchor structure 7 to the carcass structure 2a, and / or application of the sides 12 on the laterally opposite surfaces of the tire being processed, for example , the built tire 2 can be removed from the primary drum 17 to be subjected to a final vulcanization process and / or other processing operations provided in the production cycle. The aforementioned configuration of the installation is such that the simultaneous construction of several tires 2 is possible with maximum flexibility. More specifically, the provision of the first and second working areas 20, 21 in the construction line of the crown structure 14 allows the simultaneous construction of several structures of anchor 7 to be carried out. In fact, the belt structure forming devices 26 and the tread forming devices 38 are adapted to operate simultaneously with each other, so that the formation of the belt structure 8 of at least one first tire in the first working area 20 is at least partially performed simultaneously with the formation of the tread 9 of at least one second tire on the respective service drum 31, in the second working area 21. If two or more extruders 38a, 38 are provided, as shown in figure 2, or other distinct elements to form

30/30 respectively at least a first and second portion of the tread 9, the formation of the tread 9 of the first tire being processed and the formation of the tread 9 of the second tire being processed will be at least partially carried out 5 simultaneously with the fabrication of the belt structure 8 of an additional tire being processed in the first working area 20. Preferably, simultaneously with the processing operation on the construction line of the structure 14, at least one carcass structure 2a is built on the construction line of the housing structure 13. Preferably, the housing structure 2a which is about to be manufactured is intended for coupling with the crown structure 7, or one of the crown structures 7 being processed in the second working area 21. The devices for coupling the crown structure 7 with the frame structure 2a, as well as construction line of the frame structure 13 with As a whole, they preferably operate at the same operating rate as the tread forming devices 9 in the second working area 21 and the belt structure forming devices 26 in the first working area 20, so that each tire being can be immediately transferred to the next job site, avoiding tire storage being processed along the facility's construction lines.

Claims (25)

1. Tire production process, characterized by the fact that it comprises: - building a carcass structure (2a); 5 - build a crown structure (7); - couple the crown structure (7) with the carcass structure (2a); wherein the construction of the carcass structure (7) comprises: - forming at least one belt layer (8a, 8b) on an auxiliary drum (22) to manufacture at least partially a belt structure (8); - turning the axially opposite side flaps (10) of said at least one belt structure (8a, 8b) on the auxiliary drum (22); - transferring the belt structure (8) from the auxiliary drum (22) to at least one service drum (31); - forming a tread (9) by wrapping at least one continuous elongated element of elastomeric material, by forming turns arranged axially side by side around the belt structure (8) carried by the service drum (31). 2. Process according to claim 1, characterized in that the action of forming, in said auxiliary drum (22), the belt structure (8) of at least one first tire being processed is carried out at least partially simultaneously with the action of forming the tread (9) of at least one second tire being processed, in said at least one service drum (31). Process according to any one of claims 1 to 2, characterized by the fact that the action of coupling the crown structure (7) with the carcass structure (2a) is performed following the same operational rate followed by the actions the tread (9) and to form the belt structure (8). Process according to any one of claims 1 to 3, characterized by the fact that in the respective service drums the construction of the crown structures (7) belonging to the respective tires being processed is carried out simultaneously. Process according to any one of claims 1 to 4, characterized by the fact that the action of forming the tread (9) of the first tire being processed and the action of forming the tread (9) of the second tire being processed are carried out at least partially simultaneously with the fabrication of the belt structure (8) of an additional tire being processed. Process according to any one of claims 1 to 5, characterized in that it additionally comprises the action of positioning and supporting said at least one service drum (31) by means of at least one robotic arm (32) during the action of transferring the belt structure (8) from the auxiliary drum (22) to said at least one service drum (31). Process according to any one of claims 1 to 6, characterized in that the construction of the crown structure (7) additionally comprises the action of circumferentially rolling up a pair of ribbon-like reinforcement inserts (8c), each of them being radially superimposed on an end edge (10a) of one of the side flaps with turns (10) of said at least one layer of strap (8a, 8b). Process according to any one of claims 1 to 7, characterized in that the construction of the crown structure (7) additionally comprises the action of circumferentially rolling at least one reinforcement element of elastomeric material longitudinally incorporating at least one cord continuous in the form of turns arranged in axial side-to-side relationship with said at least one belt layer (8a, 8b), in which the winding of said reinforcement element can be carried out in the belt structure (8) transferred to the service drum (31). Process according to any one of claims 1 to 8, characterized in that the transfer of the belt structure (8) from the auxiliary drum (22) to said at least one service drum (31) comprises the actions of : - removing the belt structure (8) from the auxiliary drum (22) by a first transfer element (34a); - engaging the belt structure (8) on the service drum (31) by the first transfer element (34a). Process according to claim 9, characterized in that the first transfer element (34a) maintains a stationary position during the transfer of the belt structure (8). Process according to any one of claims 1 to 10, characterized in that the coupling of the crown structure (7) with the carcass structure (2a) comprises the action of transferring the crown structure (7) from the drum service (31) for a primary drum (17) that carries the carcass structure (2a), where the transfer of the crown structure (7) from the service drum (31) to the primary drum (17) comprises the actions to: - remove the crown structure (7) from the service drum (31) by a second transfer element (39); - engage the crown structure (7) on the primary drum (17) by the second transfer element (39). 12. Tire production facility, characterized by the fact that it comprises: - a construction line for carcass structures (13); - a construction line for the crown structure (14); - an assembly location (15) in which each crown structure 5 (7) is coupled with one of the frame structures (2a); wherein said construction line for crown structures (14) comprises: - at least one auxiliary drum (22); - at least one service drum (31); - devices for forming a belt structure (8) on said auxiliary drum (22), said devices comprising elements for forming at least one belt layer (8a, 8b) and elements for returning axially opposite side flaps (10) from said at least one belt layer (8a, 8b) on said auxiliary drum; - transfer devices (34) for transferring a belt structure (8) at least partially formed in the auxiliary drum (22) to said at least one service drum (31); - devices for forming a tread (9) by wrapping at least one continuous elongated element of elastomeric material, by forming turns arranged in mutual side-by-side around the belt structure (8) carried by the service drum (31) . Installation according to claim 12, characterized in that the belt structure forming devices (26) and the tread forming devices (38) operate simultaneously with each other, in the belt structure ( 8) and the tread (9), respectively, of the respective tires being processed. 14. Installation according to any of the claims 12 and 13, characterized by the fact that the belt structure forming devices (26) and the tread forming devices (38) operate simultaneously with the manufacture of at least one carcass structure (2a) in the line. construction of carcass structure (13). Installation according to any one of claims 12 to 14, characterized in that said crown structure construction line (14) comprises: - a first working area (20) in which said at least one auxiliary drum (22) is operationally arranged; - a second working area (22) in which said at least one service drum (31) is operationally arranged; and - a first transfer location (33) in which said transfer devices (34) operate. 16. Installation according to any one of claims 12 to 15, characterized in that said elements for forming at least one layer of belt (8a, 8b) comprise a feeding unit (27) to supply at least one article manufactured in the form of a strip of elastomeric material comprising textile cords in a first working place (24), designed to wrap said at least one article manufactured around the auxiliary drum (22). Installation according to any one of claims 12 to 16, characterized in that said devices for forming a belt structure (8) additionally comprise a feeding unit (30) to supply a pair of reinforcement inserts (8c ) tape-like in a second working place (25) designed to wrap said tape-like reinforcement inserts (8c) around said at least one strap layer (8a, 8b). 18. Installation according to any of the claims 12 to 17, characterized by the fact that said devices for forming a belt structure (8) comprise a means of transport (23) that transports the auxiliary drum (22) and movable to selectively position said auxiliary drum (22) in the front of at least one of the first workplace (24) and 5 of the second workplace (25). Installation according to any one of claims 12 to 18, characterized in that said elements for turning the axially opposite side flaps (10) of said at least one strap layer (8a, 8b) are preferably at least partially integrated in said auxiliary drum (22). Installation according to any one of claims 12 to 19, characterized in that said crown structure construction line (14) additionally comprises winding devices (35) for circumferentially winding at least one material reinforcing element elastomeric in turns arranged axially side by side around said at least one layer of strap (8a, 8b), whose reinforcement element longitudinally incorporates at least one continuous cord, in which said winding devices (35) operate in the structure of belt (8) carried by the service drum (31) at a third workplace (36). 21. Installation according to any one of claims 12 to 20, characterized in that said at least one service drum (31) is locked with at least a third and four workplaces (37). 22. Installation according to claim 21, characterized in that it comprises at least a first service drum (31a) and a second service drum (31b) operating simultaneously in one of said third and fourth workplaces (37) . Installation according to any one of claims 12 to 22, characterized in that the transfer devices (34) comprise a first transfer element (34a) to be alternately positioned around the auxiliary drum (22) and around 5 service drum (31). 24. Installation according to claim 23, characterized in that the first transfer element (34a) is substantially fixed in said crown structure construction line (14). Installation according to any one of claims 12 to 24, characterized in that it comprises a second transfer location (16) including at least one second transfer element (39) which can be alternately positioned around the service drum (31) and around a primary drum (17) operating on the carcass structure construction line (13).