IT202000014677A1 - METHOD FOR PACKAGING TIRE BELTS FOR VEHICLE WHEELS - Google Patents

Description

Method of making vehicle wheel tire belt packs

DESCRIPTION

The present invention relates to a method for making belt packs for vehicle wheel tyres.

A tire for vehicle wheels generally comprises a carcass structure, a crown structure arranged radially external to the carcass structure and a pair of sidewalls representing the axially outer surfaces of the tire with respect to a center plane perpendicular to the axis of rotation of the same tyre.

The carcass structure comprises at least one carcass ply formed by reinforcing cords incorporated in a matrix of elastomeric material. Does the carcass ply have opposing end flaps? respectively engaged to annular anchoring structures. The latter are located in the areas of the tire usually identified with the name of ?beads? and are normally formed each by an annular insert, or ?circle?, substantially circumferential on which ? applied, in a radially external position, at least one filler insert tapering radially away from the axis of rotation.

Specific reinforcing inserts can be provided at the beads, having the function of improving the transmission of torque to the tyre.

In the case of ?tubeless? tires, i.e. without an inner tube, a layer of elastomeric material, generally known as a ?liner?, can also be provided in a radially internal position with respect to the carcass structure to provide the necessary impermeability? to the tire inflation air. Generally, the liner extends from one heel to the other.

The crown structure comprises a belt structure and, in a radially external position to the belt structure, a tread band made of elastomeric material.

The belt structure comprises a belt layer, or more? belt layers placed in radial overlap with respect to each other, having/the reinforcing cords orientated substantially parallel to the circumferential development direction of the tire (belt layer at zero degrees) or, in the case of multiple? belt layers, cross-oriented. In the latter case, in a radially external position to the cross-oriented belt layers it can? said belt layer at zero degrees be provided.

Longitudinal and transversal grooves are typically shaped on the tread band, arranged to define a desired tread pattern. Between the tread band and the belt structure can? a so-called ?substrate of the tread band? in proprietary elastomeric material? suitable for obtaining a stable union of the belt structure with the tread band itself.

The sidewalls are made of elastomeric material and define the axially outer surfaces of the tyre, i.e. the surfaces arranged in the axially closest position? external to the annular anchoring structures, to the carcass ply/s, to the belt layer/s and possibly to at least a portion of the tread band. For example, the sides each extend from one of the lateral edges of the tread band up to the respective annular structure for anchoring to the heels.

In the continuation of this description and in the claims, any numerical value ? intended preceded by the term ?approximately? to also indicate any numerical value which deviates slightly from that indicated, for example to take into account the dimensional tolerances typical of the reference sector.

With ?elastomeric material? it is intended to indicate a composition comprising at least one elastomeric polymer and at least one reinforcing filler. This composition can also include additives such as, for example, a crosslinking agent and/or a plasticizer. Thanks to the presence of the cross-linking agent, this material can be cross-linked by heating, cos? to form the final product.

With the term ?green tyre? refers to a tire obtained from the packaging process and not yet molded and vulcanised.

With the term ?finished tyre? refers to a tire obtained by subjecting a green tire to a molding and vulcanization process.

With the term ?pneumatic? refers to a finished tire or a green tire.

The terms "axial", "axially", "radial", "radial", ?circumferential? and ?circumferentially? are used in reference to the tire or a forming drum used in the tire manufacturing process.

In particular, the terms "axial" and "axially" mean references/quantities arranged/measured or extending in a direction substantially parallel to the rotation axis of the tire or of the forming drum.

The terms "radial" and "radically" mean references/quantities arranged/measured or extending in a direction substantially perpendicular to the rotation axis of the tire or of the forming drum and lying in a plane including this rotation axis.

With the terms ?circumferential? and ?circumferentially? are references/quantities arranged/measured or extending along a circumference which develops around the rotation axis of the tire or of the forming drum.

With ?structural component? of a tire means any portion of it capable of carrying out its own function or a part thereof. For example, the following components are structural components of the tyre: the carcass structure, the crown structure, or parts of them, such as liner, underliner, anti-abrasive inserts, bead core, filler inserts in the bead area (and therefore the annular anchoring structures defined by circles and respective filler inserts), carcass ply(s), belt layer(s), belt underlayer, tread band underlayer, sidewalls, sidewall inserts, tread band, reinforcing inserts in textile or metallic material, reinforcing inserts in elastomeric material etc., or a part thereof.

With ?cross belt structure? it is intended to indicate a belt structure comprising at least two belt layers placed in radial superposition with respect to each other and each including a plurality of of parallel textile and/or metallic and/or hybrid reinforcing cords, inclined with respect to the circumferential development direction of the tire (and therefore to an axial center plane of the tyre), in which the reinforcing cords of a belt layer are inclined with respect to said axial center plane of the tire of the same angle and on the opposite side to the reinforcing cords of another belt layer.

With ?belt pack? it is intended to indicate an annular assembly comprising a crossed belt structure and a zero degree belt layer arranged in a radially external position with respect to the crossed belt structure.

With ?cylindrical conformation? of a pack of belts is meant to indicate a manufacturing cycle aimed at obtaining a pack of belts with a substantially cylindrical shape.

With ?toroidal conformation? of a pack of belts is intended to indicate a manufacturing cycle aimed at obtaining a pack of belts having a substantially toroidal shape and having a radial sectional profile close to the radial sectional profile of the corresponding finished tyre.

By "substantially toroidal forming drum" we mean a forming drum whose outer surface has a radial section profile such that, whatever semi-finished product is deposited thereon during the manufacturing of a tire being processed, the semi-finished product assumes a conformation close to that which it has in the finished tyre.

With ?tire in progress? it is intended to indicate a tire in any phase of the relative production process which goes from the packaging of at least one structural component to obtaining the finished tyre. For example, a tire being worked on? the one that comes out of the work station dedicated to packing the belt pack to proceed towards the work stations dedicated to placing on the belt pack any underlayer of the tread band, any reinforcing inserts and the tread band itself.

With ?functionally independent? do you mean the capacity? of an organ or device to perform the function prescribed to it autonomously, without cio? interact or cooperate with other bodies or devices intended to perform the same function.

With ?operation at steady state? they mean the normal operating conditions of a tire production plant, thus excluding any transient start-up or shutdown periods of the plant itself, for example, linked to a change of production lot.

With ?cycle time of a packaging device? it is meant to indicate the time which elapses between the exit of a tire being processed from the packaging device and the exit of the following tire being processed from the same packaging device, under steady state operating conditions. The cycle time of a packaging device? therefore given by the sum of the time necessary to load the tire being worked on in the packaging device, of the time necessary to carry out the activity? packing time, and the time required to unload the tire being processed from the packing device.

With ?total cycle time of a packaging plant? it is meant to indicate the time that elapses between the exit of a tire being processed from the packaging plant and the exit of the following tire from the same packaging plant, in full operating conditions.

The expressions ?valley?/?head? and ?mount?/?tail? are used referring to a movement direction. Therefore, assuming for example a movement direction from left to right, a position ?downstream? or ?head? with respect to any reference element it indicates a position to the right of said reference element and a position ?upstream? or ?tail? indicates a position to the left of said reference element.

The production cycles of a tire provide that, after a green tire packaging process in which the various structural components of the tire itself are packaged and assembled, the green tires are transferred to a molding and vulcanization line where a process is implemented of molding and vulcanization able to define the structure of the finished tire according to a desired geometry and tread pattern.

The packaging of the structural components of the tires and their subsequent assembly take place on special forming drums. For example, the carcass structure can? be packed on a first forming drum, known as a first stage drum, and the crown structure can be packaged on a second forming drum, known as an auxiliary or second stage drum. The assembly of the carcass structure to the crown structure can? take place on the first forming drum, in which case the first stage drum is referred to as a unistage drum, or on a different forming drum, known as a shaping drum.

An example of a green tire production plant? described in WO2010/070374. This plant includes:

- at least one line for packaging the carcass structure on a first forming drum, this packaging line comprising a plurality of? of workstations arranged according to a sequential series; And

- at least one packaging line of the crown structure on at least a second forming drum, this packaging line comprising a plurality of? of workstations arranged according to a sequential series; And

- at least one station for shaping and assembling the tire being manufactured suitable for shaping the carcass structure on the first forming drum by assembling it to the crown structure of the tire being manufactured.

Examples of first stage and/or second stage forming drums usable in a tire production process such as the one described in the aforementioned WO2010/070374 are disclosed in WO2008/152453 and US2012/0318460. In both cases, these are radially shrinkable/expandable forming drums having a substantially cylindrical shape.

The forming drums described in the cited documents are widely used in tire production cycles where ? a cylindrical conformation of the belt packs is foreseen.

The Applicant has observed that, for example in the production cycles of racing or high performance tyres, ? necessary to be able to adequately control the deformations to which ? subjected the green tire during the molding and vulcanization process, in order to give the tire the desired reactivity? and driving precision. To be able to do this, ? It is advisable to provide, before carrying out the molding and vulcanization process, a toroidal shape such as to give the belt pack a substantially toroidal shape which is the most? close as possible to that of the finished tyre.

With a view to creating a technologically and operationally flexible production plant, so? to reduce the construction costs of the plant and its devices and apparatuses and the spaces occupied by such devices and apparatuses, the Applicant has deemed it appropriate to identify a suitable solution to implement, through the same belt pack packaging device, both a conformation cylinder of the belt pack and a toroidal conformation of the belt pack, choosing each time which of the two types of conformation to implement according to the type of tire to be produced.

The Applicant has observed that this solution could provide for the packaging of the belt pack on a substantially cylindrical forming drum when it is desired to implement a cylindrical shape of the belt pack, and on a substantially toroidal forming drum when it is desired to implement a toroidal shape of the belt pack .

According to the Applicant for? it would be extremely difficult to be able to join automatically (ie? not manually) the portions of the end? of the belt layers of the crossed belt structure if these belt layers (each of which is defined by a substantially flat strip-shaped blank cut to size) were deposited on a substantially toroidal forming drum.

The Applicant has therefore considered it preferable to identify an alternative solution which provides for the packaging of the crossed belt structure on a substantially cylindrical forming drum not only in the case of a cylindrical shape of the belt packs but also in the case of a toroidal shape of the belt packs, using the same forming drum for the subsequent deposition of the belt layer at zero degrees in the case of a cylindrical conformation of the belt packs and a different forming drum for the subsequent deposition of the belt layer at zero degrees in the case of a toroidal conformation of the belt packs. In fact, this last operation, since it does not require the creation of joints, can be implemented on a forming drum having any shape, even toroidal.

Finally, has the Applicant found that ? It is possible to envisage a belt pack packaging cycle having a first part of the cycle, dedicated to the packaging of the crossed belt structure, in which a substantially cylindrical forming drum is used both when it is desired to implement a cylindrical conformation of the belt packs both when it is desired to implement a toroidal conformation of the belt packs, and a second part of the cycle, dedicated to the deposition of the belt layer at zero degrees, in which when it is desired to implement a cylindrical conformation of the belt packs, one continues to make use of the aforementioned drum substantially cylindrical forming, while when it is desired to implement a toroidal conformation of the belt packs, the crossed belt structure is taken from the substantially cylindrical forming drum and transferred to another forming drum after having been toroidally shaped, to then proceed with the deposition of the zero degree belt layer on the toroidally shaped cross belt structure.

The present invention therefore relates to a method for making a pack of belts for a tire for vehicle wheels.

Preferably, it is envisaged to manufacture a crossed belt structure on a first substantially cylindrical forming drum.

Preferably, depending on the type of tire to be produced, one chooses whether to manufacture a pack of belts having a cylindrical shape or a pack of belts having a toroidal shape.

Preferably, to manufacture a pack of belts of cylindrical shape, the method comprises depositing at least one layer of belt at zero degrees on said first forming drum in a radially external position with respect to said crossed belt structure.

Preferably, in order to manufacture a pack of toroidal-shaped belts, the method comprises taking said crossed belt structure from said first forming drum.

Preferably, in order to manufacture a belt pack of toroidal conformation, the method comprises toroidally shaping said crossed belt structure.

Preferably, in order to manufacture a pack of toroidal-shaped belts, the method comprises transferring said toroidally-shaped crossed belt structure onto a second forming drum.

Preferably, to manufacture a pack of toroidal-shaped belts, the method comprises depositing at least one layer of belt at zero degrees on said second forming drum in a radially external position with respect to said toroidally-shaped crossed belt structure.

The Applicant believes that the method according to the invention allows to carry out both a cylindrical shape of the belt packs and a toroidal shape of the belt packs by means of the same packaging device, thus minimizing the number of devices and equipment used and the spaces occupied by these devices and equipment. There? thanks to the fact that the cross belt structure ? packaged on a substantially cylindrical forming drum, both when it is desired to implement a cylindrical shape of the pack of belts, and when it is desired to implement a toroidal shape of the pack of belts.

Furthermore, thanks to the fact that, when it is desired to implement a toroidal conformation of the belt pack, the zero-degree reinforcing layer is deposited on a crossed belt structure which is? previously been shaped toroidally, ? is it possible to join automatically (ie? not manually) and without difficulty? the portions of extremity? of the belt layers of the cross belt structure.

The present invention can have at least one of the preferred characteristics described below.

Preferably, said cross belt structure ? packaged on said first substantially cylindrical forming drum in a first working area. There? both when a cylindrical conformation of the belt pack is desired and when a toroidal conformation of the belt pack is desired

Once the crossed belt structure has been made on the first forming drum, different expedients are envisaged depending on whether it is desired to implement a cylindrical shape of the belt pack or a toroidal shape of the belt pack.

Preferably, said at least one zero degree belt layer? deposited on said first forming drum (for making a pack of belts of cylindrical shape) or on said second forming drum (for making a pack of belts of toroidal shape) in a second work area.

Preferably, said second work area ? arranged downstream of said first working area with reference to a first movement direction.

Preferably, when is it desired to implement a toroidal conformation of the belt pack called crossed belt structure? toroidally shaped in a first service area.

Preferably, said first service area ? arranged downstream of said second working area with reference to said first movement direction.

Preferably, to manufacture a pack of belts of cylindrical shape, said first forming drum ? moved along said first direction of movement from said first work area to said second work area.

Preferably, to manufacture a pack of belts of cylindrical shape, said first forming drum ? moved along said first direction of movement from said second work area to a second service area.

Preferably, said second service area ? arranged downstream of said first service area with reference to said first movement direction.

Preferably, when a pack of belts of cylindrical shape is made, during movement from said second work area to said second service area, the first forming drum crosses said first service area without stopping there.

Preferably, in order to manufacture a toroidal-shaped belt package, said first forming drum ? moved along said first movement direction from said first work area to said first service area crossing said second work area without stopping there.

Preferably, when a toroidal-shaped belt package is made, said second forming drum ? moved from said first service area to said second work area along a second direction of movement opposite to said first direction of movement. This movement therefore takes place along a path which is partly identical to that of the first forming drum, with consequent optimization of space.

Preferably, after having moved said second forming drum from said first service area to said second working area, said second forming drum ? moved from said second work area along said first direction of movement crossing said first service area without stopping there.

Preferably, before moving said second forming drum from said first service area to said second working area, said second forming drum ? moved from a second service area to said first service area along said second feed direction.

Preferably, said second service area ? arranged downstream of said first service area with reference to said first movement direction.

Preferably, toroidally shaping said crossed belt structure comprises transferring said crossed belt structure from said first forming drum to an annular holding member.

Preferably, said annular holding member ? arranged in said first service area.

Preferably, toroidally shaping said crossed belt structure comprises arranging said second forming drum in a position radially inside said annular retaining member.

Preferably, toroidally shaping said crossed belt structure comprises, after having arranged said second forming drum in a position radially inside said annular retaining member, radially expanding said second forming drum until it is brought into an expanded condition.

Preferably in said expanded condition said second forming drum ? in contact with said crossed belt structure and deforms said crossed belt structure until it assumes a toroidal shape.

Preferably, transferring said cross-belt structure from said first forming drum to said annular retaining member comprises placing said first forming drum in a radially internal position with respect to said annular retaining member.

Preferably, transferring said crossed belt structure from said first forming drum to said annular retaining member comprises radially contracting said annular retaining member until it comes into contact with said crossed belt structure.

Preferably, transferring said crossed belt structure from said first forming drum to said annular retaining member comprises, after radially contracting said annular retaining member, radially contracting said first forming drum leaving said crossed belt structure in load of said member holding ring.

Preferably, said second forming drum ? essentially toroidal.

In preferred embodiments, the first forming drum is radially contractible/expandable.

In the above preferred embodiments or in further preferred embodiments, the second forming drum is radially contractible/expandable.

In the aforementioned preferred embodiments or in further preferred embodiments, the annular holding member is? radially contractible/expandable.

Further characteristics and advantages of the present invention will become clearer from the following detailed description of a preferred embodiment thereof, made with reference to the attached drawings.

In such drawings:

- figure 1 ? a schematic view of a radial half-section of a tire which can be produced by means of a process and plant in which the method of the invention is carried out;

- figure 2 ? a schematic top view of a plant for the production of tires for vehicle wheels in which an embodiment of the method of the invention is carried out;

- figures 3-17 are schematic top views of a belt pack manufacturing line of the plant of figure 2 in its various operating configurations assumed during the actuation of a toroidal shape of the belt pack in accordance with the method of the invention ;

- figure 18 ? a schematic front view of an annular holding member provided in the packaging line of figures 3-17;

- figures 19-20 are schematic perspective views of a manipulator provided in the packaging line of figures 3-17, in two of its different operating configurations:

- figures 21 and 22 are schematic top views of a belt pack packaging line of the plant in figure 2 in its various operating configurations assumed during the implementation of a cylindrical shape of the belt pack in accordance with the method of the invention .

In figure 1, with 2 ? indicated an example of a tire that pu? be produced in a plant for the production of tires for vehicle wheels. This tire can be produced by carrying out the method of the present invention.

The tire 2 has a center line A perpendicular to its rotation axis R (in figure 2 the position of the rotation axis R with respect to the section of the tire 2 is shown in a wholly indicative and schematic way). The centerline plane A divides the tire 2 into a first half? axial 2a and in a second half? axial. For simplicity? of illustration, figure 2 shows only the first half? axial 2a of the tire 2, the other half? being substantially specular (unless the tread pattern which may not be symmetrical with respect to the aforementioned center line A).

The tire 2 essentially comprises a carcass structure 3 having one or two carcass plies 4a, 4b. A layer of waterproof elastomeric material or so-called liner 5 ? applied internally to the carcass ply/s 4a, 4b.

Two annular anchoring structures 6 (of which only that of the axial half 2a is shown in figure 2) are engaged, in axially opposite positions (with respect to the centerline plane A), at respective end edges of the carcass ply(s) 4a, 4b. The two annular anchoring structures 6 each comprise a so-called small ring 6a carrying, in a radially external position, an elastomeric filler 6b. Are the two annular anchoring structures 6 integrated in the vicinity? of areas usually identified with the name of "beads" 7 (of which only that of the axial half 2a is shown in figure 2), in correspondence of which the engagement usually takes place between the tire 2 and a respective mounting rim.

In a radially external position to the frame structure 3 ? arranged a crown structure 9? including a belt pack 8? and a tread band 9 disposed in a radially external position to the pack of belts 8?.

The belt pack 8? comprises a cross-belt structure 8 comprising two radially superimposed belt layers 8a, 8b, and a zero-degree belt layer 8c arranged in a radially external position to the cross-belt structure 8.

The crossed belt structure 8 can be associated with so-called "under-belt inserts" 10 each positioned between the carcass ply(s) 4a, 4b, and one of the axially opposite end edges of the crossed belt structure 8.

Two sidewalls 11, each extending from the corresponding bead 7 to a corresponding lateral edge of the tread band 9, are applied in axially opposite positions (with respect to the centerline plane A) on the carcass ply/s 4a, 4b. The whole of the portion of each sidewall 11 close to the respective lateral edge of the tread band 9 and of each portion of the tread band 9 close to the respective sidewall 11? known as shoulder 12 of tire 2.

Figure 2 shows a plant 1 for the production of tires 2 for vehicle wheels in which an embodiment of the method of the invention is carried out.

Plant 1 comprises a carcass structure manufacturing line 100, a crown structure manufacturing line 200, a shaping and assembly machine 300 for obtaining a green tire 2? and a molding and vulcanization station 400 for obtaining the finished tire 2.

In a steady state operation of the plant 1, the carcass structure packaging line 100 comprises a plurality of of work stations (such as for example the one indicated below with the reference numeral 125) comprising respective packaging devices configured to package a plurality of of carcass structures on respective forming drums 110 taken from a first drum storage area 111.

Similarly, the crown structure packaging line 200 comprises a plurality of of work stations (such as for example the one illustrated in figures 3-17) comprising respective packaging devices configured to package a plurality of of crown structures on respective forming drums 210 taken from a second drum storage area 211.

Preferably, the forming drums 110 are substantially cylindrical.

On the other hand, with regard to the forming drums 210, they are substantially cylindrical in the case in which it is desired to implement a cylindrical shape of the pack of belts or substantially toroidal in case in which it is desired to implement a toroidal shape of the pack of belts.

Will it be done in the following? always referring to forming drums 210 of substantially toroidal shape, unless expressly stated otherwise.

The carcass structure packaging line 100 comprises a first path 120 comprising packaging devices configured to deposit a first part of structural components of the carcass structure on the forming drum 110.

The first path 120 of the carcass structure packaging line 100 comprises, for example:

- a liner application station;

- an underliner application station;

- at least one station for applying a carcass ply; - an optional station for applying metal and/or textile reinforcements;

- an optional station for applying inserts under the belt.

The carcass structure packaging line 100 further comprises a second path 130 comprising packaging devices configured to package a second part of structural components of the carcass structure on the forming drum 110.

The second path 130 of the carcass structure packaging line 100 comprises, for example:

- a station for applying anti-abrasive inserts by spiraling a continuous longiform element around the forming drum 110;

- an optional station for applying at least a portion of sides by spiraling a continuous longiform element around the forming drum 110.

Preferably, the first path 120 of the carcass structure packaging line 100 is essentially straight.

Preferably, the second path 130 of the carcass structure packaging line 100 is substantially rectilinear and orthogonal to the first path 120.

In a corner area between the first path 120 and the second path 130 of the carcass structure packaging line 100 ? arranged a work station 125 configured to form the tire beads.

The carcass structure packaging line 100 further comprises a first transfer device 121 suitable for transferring the forming drum 110 from the first path 120 to the bead forming station 125 and a second transfer device 122 suitable for transferring the forming drum 110 from the bead forming station 125 at the second path 130.

Each of these transfer devices 121, 122, can include an anthropomorphic robot (for example a robotic arm with at least 6 movement axes) or a non-anthropomorphic Cartesian movement device, which allows movement according to three Cartesian axes X, Y, Z and, preferably, rotation around at least one, more preferably to two of said Cartesian axes X and Y. The X and Y axes are indicated in figure 2; the Z axis? perpendicular to the X and Y axes.

Preferably, each forming drum 110 can be moved between the various workstations of the carcass structure packaging line 100 in a sequence equal to or different from the spatial sequence of these workstations.

Preferably, along the first path 120 of the carcass structure building line 100, each forming drum 110 is moved by means of a carriage (not shown). The cart ? preferably capable of moving, controlled by a suitable motor, along suitable guides (preferably rectilinear) in two opposite directions of travel.

Along the first path 120 of the carcass structure packaging line 100, the packaging of the first part of components of the carcass structure is preferably carried out with the forming drum 110 associated with a pair of axially opposite support rings (not shown).

In the bead forming station 125 and along the second path 130 of the carcass structure building line 100, the forming drum 110 is formed. dissociated from the aforementioned pair of support rings.

The crown structure packaging line 200 comprises a first path 220 comprising packaging devices configured to package a first part of structural components of the crown structure on the forming drum 210.

The first path 220 of the crown structure packaging line 200 comprises, for example:

- an optional station for applying inserts under the belt (present unless this station is already included in the first path 120 of the carcass structure packaging line 100);

- at least one belt pack packing station;

- an optional substrate application station.

The crown structure packaging line 200 further comprises a second path 230 including packaging devices configured to package a second part of structural components of the crown structure.

The second path 230 of the crown structure packaging line 200 comprises, for example:

- at least one station for applying the tread band by coiling a continuous longiform element around the forming drum 210;

- an optional station for applying at least a portion of the sides by spiraling a continuous longiform element around the forming drum 210. This last station? at least present either in said second path 130 of the carcass structure packaging line 100 or in said second path 230 of the crown structure packaging line 200.

The crown structure packaging line 200 also comprises a drum transfer device 221 suitable for transferring the forming drum 210 from the first path 220 to the second path 230.

The 221 drum transfer device can include an anthropomorphic robot (for example a robotic arm with at least 6 movement axes) or a non-anthropomorphic Cartesian movement device, which allows movement according to three Cartesian axes X, Y, Z and, preferably, rotation around at least one, more preferably to two of said Cartesian axes X and Y.

Preferably, each forming drum 210 can be moved between the various workstations of the crown structure packaging line 200 in a sequence equal to or different from the spatial sequence of these workstations.

Preferably, the first path 220 of the crown structure packaging line 200 is essentially straight.

Pi? preferably, the first path 220 of the crown structure packaging line 200 is substantially parallel to the first path 120 of the carcass structure packaging line 100.

Preferably, the second path 230 of the crown structure packaging line 200 is substantially straight and orthogonal to the first path 220.

The 300 Conformation and Assembly Machine? adapted to sequentially shape, one at a time, the carcass structures, as they arrive from the carcass structure manufacturing line 100, and assemble them to the respective crown structures, as they arrive from the crown structure manufacturing line 200, as follows: to get respective green tires 2?. In the specific example illustrated here, the conformation and assembly machine 300 is suitable for shaping the carcass structures and assembling them to the respective crown structures on a shaping drum 330. It therefore operates on carcass structures and crown structures that are dissociated from the respective forming drums 110 and 210. These forming drums 110 and 210 are moved to return to the respective storage areas 111 and 211.

The green tires 2? packed, leaving the conformation and assembly machine 300, are transferred to the molding and vulcanization station 400 where a molding and vulcanization process is carried out suitable for defining the structure of the tire according to a desired geometry and tread pattern, thus obtaining the finished 2 tires.

With reference to figures 3-17, the crown structure packaging line 200 comprises a device 201 for packaging the belt package. Preferably, this device 201 ? arranged at the first path 220 of the crown structure packaging line 200.

The device 201 for assembling the belt package comprises a trolley 21 which can be moved on a substantially straight track 21a. Platform 21a ? arranged in such a way as to achieve movement of the carriage 21 along a rectilinear movement direction A, which ? preferably parallel to the first path 220 of the crown structure packaging line 200, and along a movement direction B opposite to the movement direction A.

As described more? forward, during its movement the trolley 21 supports a substantially cylindrical forming drum 25 in order to pack a belt pack or only part of it on it, depending on whether it is desired to implement a cylindrical shape of the belt pack (in which case the carriage 21 always supports only the substantially cylindrical forming drum 25) or a toroidal shape of the belt pack (in which case the carriage 21 supports the substantially cylindrical forming drum 25 for a first part of the belt pack manufacturing process and the substantially toroidal forming 210 for the remaining part of the belt package manufacturing process).

The forming drums 25 and 210 are radially contractable/expandable. Both include a plurality? of radially synchronous angular sectors. The angular sectors of the forming drum 25 are shaped so as to give the forming drum 25 a substantially cylindrical geometry whatever its radial dimension, while the forming drums 210 are shaped so as to give the forming drum 210 a substantially toroidal whatever its radial dimension.

The belt package packaging device 201 comprises a first work area W1 arranged downstream of a starting position P0 of the trolley 21 with reference to the movement direction A and a second work area W2 arranged downstream of the first work area W1 with reference to the movement direction A. The starting position P0 can? also be defined in the first workspace W1.

The first working area W1 comprises a device 22 for making a crossed belt structure. For this purpose, the first work area W1 comprises a first operating station W1a comprising an apparatus 22a for deposition of a first layer of belt having a plurality of? of first inclined reinforcing cords with a first orientation and a second operating station W1b arranged downstream of the first operating station W1a with reference to the direction of movement A and comprising an apparatus 22b for deposition of a second belt layer having a plurality of second inclined reinforcing cords with a cross orientation with respect to that of the aforementioned first cords.

The second working area W2 comprises a device 23 for deposition of a zero degree belt layer.

The belt package packaging device 201 comprises, downstream of the second work area W2 with reference to the movement direction A, a first service area S1.

The first service area S1 comprises an annular holding member 30, illustrated in greater detail in figure 18.

The annular holding member 30 comprises a base 31 and an annular body 32 integrally associated with the base 31.

The annular body 32 comprises a plurality of angular sectors 35 (eight in the specific example illustrated in figure 18) circumferentially adjacent to each other and radially movable in a synchronous manner, preferably following a suitable electric or pneumatic command, between a radially more operating position? external and a non-operative position radially more? internal. As a result of the possibility movement of the angular sectors 35 the annular holding member 30 ? therefore radially contractible/expandable.

In figure 18 the angular sectors 35 are illustrated in their inoperative position. This non-operative position corresponds to the configuration of maximum radial contraction of the annular retention member 30.

With reference to figures 3-17, the device 201 for assembling the belt package also comprises, downstream of the first service area S1 with reference to the movement direction A, a second service area S2.

In the second service area S2 two support members 41 and 45 are provided. The support member 41 is provided. configured to support a first forming drum (e.g., the forming drum 25 illustrated in FIGS. 19 and 20), while the support member 45 is configured to support a first forming drum (e.g., the forming drum 25 illustrated in FIGS. configured to support a second forming drum (e.g., forming drum 210 shown in Figures 19 and 20 ).

In the particular embodiment illustrated in figures 19 and 20, the two support members 41, 45 are part of a single manipulator 40.

The manipulator 40 ? immovably disposed in the second service area S2, i.e. when used it always remains in the same position with respect to the ground.

The manipulator 40 comprises a base frame 40a resting stably on the ground and a movable unit 40b which rotates with respect to the base frame 40a about an axis of rotation R oblique with respect to the ground. In particular, the axis of rotation R ? inclined at an angle equal to 45? compared to the ground.

The mobile group 40b ? associated with a service surface 44 of the base frame 40a. This service area? inclined at an angle equal to 45? compared to the ground.

The two support members 41, 45 are integrally associated with the movable group 40b, so that the rotation of the mobile unit 40b with respect to the base frame 40a around the axis of rotation R involves the rotation of the support members 41, 45 around the axis of rotation R. This rotation can? be controlled by a motor unit not visible in the figures. The angle of rotation can? be set as desired.

Each support member 41, 45 comprises a respective support arm 42, 46, and a respective mounting axis. When the support member 42, 46 supports a respective forming drum, its mounting axis is ? coinciding with the axis of rotation of the respective forming drum.

The two support arms 42, 46 extend in directions substantially perpendicular to each other and are configured to support the forming drums in such a way that the mounting axis of one of the two support members 41, 45, (and therefore the rotation axis of one of the two forming drums) is arranged along a substantially horizontal direction and the assembly axis of the other support member 41, 45 (and therefore the rotation axis of the other forming drum forming) is arranged along a substantially vertical direction.

In the operating configuration shown in figure 19, the support arm 42 supports the substantially cylindrical forming drum 25 in such a way that the support member 41 is in a loading/unloading position and the rotation axis of the forming drum 25 (and therefore the mounting axis of the support member 41) is arranged along a horizontal direction, while the support arm 46 supports the substantially toroidal forming drum 210 in such a way that the support member 45 is located in a standby position and the rotation axis of the forming drum 210 (and therefore the mounting axis of the support member 45) is disposed along a vertical direction.

In the operative configuration illustrated in figure 20, the movable group 40b has rotated by 180? around the axis of rotation R. In this configuration the support members 41, 45 have exchanged positions, so that? the support arm 42 supports the substantially cylindrical forming drum 25 in such a way that the support member 41 is in the aforementioned standby position and the rotation axis of the forming drum 25 is arranged along the aforementioned vertical direction, while the support arm 46 supports the substantially toroidal forming drum 210 in such a way that the support member 45 is in the aforementioned loading/unloading position and the rotation axis of the forming drum 210 is disposed along the aforementioned horizontal direction.

Each forming drum 25, 210, ? supported by the respective support arm 42, 46, by means of a respective compensator device 43, 47, able to compensate for any axial displacements of the forming drum 25, 210.

Preferably, each compensator device 43, 47 comprises a plurality of of pneumatic cylinders, at least some of which are functionally independent from the others cos? to allow for a different degree of compensation depending on whether the forming drum 25, 210, ? arranged with its axis of rotation extended along a horizontal or vertical direction.

How already? said, the device 201 for assembling the belt package allows to carry out both a cylindrical conformation of the belt package and a toroidal conformation of the belt package.

When it is desired to implement a toroidal shape of the belt pack, the device 201 for packaging the belt pack is arranged to assume the operating configuration shown in figure 3, in which the trolley 21 is? in its starting position P0 (or in the first working area W1 if the starting position P0 is defined in the first working area W1) and supports a substantially cylindrical forming drum 25. In this operating configuration, the support arm 42 of the manipulator 40 is oriented so that the support member 41 is arranged in the aforementioned loading/unloading position (and therefore the mounting axis of the support member 41 is oriented along a horizontal direction), while the support arm 46 is oriented. oriented so that the support member 45 is arranged in the aforementioned standby position (and therefore the mounting axis of the support member 45 is oriented along a vertical direction) and supports a substantially toroidal forming drum 210, as illustrated in figure 19.

Subsequently, the carriage 21 with the forming drum 25 is moved along the movement direction A until the forming drum 25 is brought into the first working area W1. Isn't this movement? implemented when the starting position P0 ? defined in the first work area W1.

As illustrated in figure 4, the trolley 21 is stopped when the forming drum 25 is at the first operating station W1a, where a first layer of belt is deposited on the forming drum 25 by means of the deposition apparatus 22a, such as for example the belt layer 8a of the tire 2 of figure 1.

As illustrated in figure 5, the carriage 21 is subsequently moved along the direction of movement A and stopped when the forming drum 25 is at the second operating station W1b, where by means of the deposition apparatus 22b one arranges to deposit on the drum forming ring 25, in a radially external position with respect to the first belt layer, a second belt layer, such as for example the belt layer 8b of the tire 2 of figure 1, thus packaging? on the forming drum 25 a crossed belt structure, such as for example the crossed belt structure 8 of the tire 2 of figure 1.

As illustrated in figure 6, the trolley 21 is subsequently moved along the direction of movement A ? stopped when the forming drum 25, carrying the crossed belt structure, reaches the first service area S1 and is arranged in a radially internal position to the annular retaining member 30.

We proceed with the transfer of the crossed belt structure from the forming drum 25 to the annular retention member 30. This transfer first provides for the radial contraction of the annular retention member 30 through synchronous radial displacement of the angular sectors 35 until the sectors angles 35 come into contact with the crossed belt structure and, subsequently, the radial contraction of the forming drum 25 through synchronous radial displacement of the relative angular sectors.

At this point the crossed belt structure remains integral with the annular retaining member 30 and the carriage 21 is moved along the movement direction A to bring the forming drum 25, without the crossed belt structure, to the second area of service S2, where it is transferred to the first support member 41, as illustrated in figure 7.

Subsequently, as illustrated in figure 8, the trolley 21 is moved along the movement direction B so as to move away from the second service area S2.

As shown in figure 9, at this point provision is made to rotate the movable unit 40b of the manipulator 40 around the axis of rotation R through an angle of 180?. This rotation involves a rotation of the support member 41 around the axis of rotation R until it is brought to the standby position originally occupied by the support member 45 and, simultaneously, a rotation of the support member 45 around the axis of rotation R until it is brought to the loading/unloading position originally occupied by the support member 41. The forming drum 25 is therefore found with its axis of rotation oriented along a vertical direction and the forming drum 210 is found with its axis oriented along a horizontal direction, as illustrated in figure 20.

Subsequently, as illustrated in figure 10, the carriage 21 is moved along the movement direction A so as to pick up the forming drum 210 from the support member 45.

Subsequently, as illustrated in figure 11, the trolley 21 is moved along the movement direction B until the forming drum 210 is placed in the first service area S1, in a radially internal position to the annular retaining member 30.

We proceed with the transfer of the crossed belt structure from the annular retaining member 30 to the forming drum 210. This transfer provides for the radial expansion of the forming drum 210 through synchronous radial displacement of its angular sectors until these angular sectors bear the forming drum 210 in an expanded condition in which the aforesaid angular sectors are in contact with the crossed belt structure supported by the annular retaining member 30. also provide for a radial expansion of the annular retaining member 30 when the forming drum 210 is been brought into the aforementioned expanded condition. The radial expansion of the annular holding member 30 can also be at least partially contemporary with the radial expansion of the forming drum 210.

Preferably, the forming drum 210 remains in the aforementioned expanded condition until the end of the crown structure building cycle.

Once the cross belt structure ? been transferred to the forming drum 210, as shown in figure 12, the carriage 21 is moved along the movement direction B to bring the forming drum 210, with the crossed belt structure, to the second working area W2, where the deposition takes place on the forming drum 210, in a radially external position with respect to the crossed belt structure, of the zero-degree belt layer, such as for example the zero-degree belt layer 8c of the tire 2 of figure 1. This results in the desired toroidal conformation of the belt pack, such as for example the belt pack 8? of tire 2 in figure 1.

Subsequently, as illustrated in figure 13, the trolley 21 is moved along the direction of movement A to carry the forming drum 210, with the pack of belts so? shaped, in correspondence with the second service area S2, where it is transferred to the second support member 45.

The trolley 21 is subsequently moved along the movement direction B so as to move away from the second service area S2, as illustrated in figure 14.

As shown in figure 15, at this point provision is made to rotate the movable unit 40b of the manipulator 40 around the axis of rotation R through an angle of 180?. This rotation involves a rotation of the support member 45 around the axis of rotation R until it is brought to the standby position previously occupied by the support member 41 and, simultaneously, a rotation of the support member 41 around the axis of rotation R until it is brought to the loading/unloading position previously occupied by the support member 45. The forming drum 210 is therefore found with its axis of rotation oriented along a vertical direction and the forming drum 25 is found with its axis oriented along a horizontal direction, as illustrated in figure 19.

Subsequently, as illustrated in figure 16, the carriage 21 is moved along the movement direction A so as to pick up the forming drum 25 from the support member 41.

Subsequently, as illustrated in figure 17, the carriage 21 with the forming drum 25 is moved along the movement direction B until it returns to its starting position P0 (or to the first working area W1 in the event that the starting position P0 is defined in the first work area W1). During this movement, the forming drum 25 moves to a radially internal position with respect to the annular holding member 30 without stopping in the first service area S1, in the second work area W2 and, if the starting position P0 is not defined in the first work area W1, in this first work area W1.

Just before, during or just after the movement of the trolley 21 to bring the forming drum 25 from the second service area S2 to the starting position P0 (or to the first working area W1 in case the starting position P0 is defined in the first work area W1), the drum transfer device 221, illustrated in figure 2, picks up the forming drum 210 from the support member 45 to send it to the path 230 of the crown structure packaging line 200 and onto the support member 45, preferably again via the drum transfer device 221, a new substantially toroidal forming drum 210?, illustrated in figure 17.

The device 201 for packaging the belt package described above can what? proceed with a new cycle of packing the belt pack with a toroidal shape, repeating the actions described above.

From the foregoing, it is evident that in the steady state operation of the plant of figure 2, a plurality of elements enter/exit in succession into/from the device 201 for packaging the belt pack. of substantially toroidal forming drums 210, 210?, while the forming drum 25 always remains inside this packaging device 201.

Preferably, in the plant of figure 2 there are 5 or 6 substantially toroidal forming drums which circulate simultaneously in the crown structure packaging line 200.

These forming drums have diameters, in the contracted configuration, preferably between 500 mm and 900 mm and allow a maximum radial expansion of 300 mm. Consequently, also the annular retaining member 30 must be able to have a similar radial expansion.

When it is desired to implement a cylindrical shape of the pack of belts, the device 201 for assembling the pack of belts is arranged to assume an operating configuration which differs from that illustrated in figure 3 due to the sole fact that the support member 45 also supports a substantially cylindrical forming drum 250, entirely equivalent to the previously described forming drum 25. The 250 forming drum ? shown in figure 21.

Subsequently, the carriage 21 with the forming drum 25 is moved along the movement direction A until the forming drum 25 is brought into the first working area W1.

In a similar way to what is illustrated in figure 4, the carriage 21 is stopped when the forming drum 25 is at the first operating station W1a, where by means of the deposition apparatus 22a the first belt layer.

In a similar way to what is illustrated in figure 5, the carriage 21 is subsequently moved along the movement direction A and stopped when the forming drum 25 is at the second operating station W1b, where, by means of the deposition apparatus 22b, the to deposit the second belt layer on the forming drum 25, in a radially external position with respect to the first layer of belt, thus packaging the? on the forming drum 25 the cross belt structure.

Subsequently, as illustrated in figure 21, the trolley 21 is successively moved along the movement direction A and stopped when the forming drum 25 reaches the second working area W2, where it is deposited on the forming drum 25 by means of the deposition device 23 , in a radially external position with respect to the crossed belt structure, the belt layer is at zero degrees, thus achieving? the desired cylindrical shape of the belt package.

Subsequently, as illustrated in figure 22, the carriage 21 is moved along the movement direction A until the forming drum 25, after having crossed the first service area S1, without stopping there and passing into a radially internal position with respect to the member retaining ring 30, reaches the second service area S2, where it is transferred to the support member 41.

Subsequently, the trolley 21 is moved along the movement direction B so as to move away from the second service area S2, in a similar way to what is illustrated in figure 8 (where however it must be understood that instead of the forming drum 210 there is the forming drum 250).

At this point, the movable group 40b of the manipulator 40 is rotated around the axis of rotation R through an angle of 180?, in a similar way to what is illustrated in figure 9 (always meaning that instead of the forming drum 210 The forming drum 250 is present). This rotation brings the forming drum 25 to the position originally occupied by the forming drum 250 and the latter to the position originally occupied by the forming drum 25. The forming drum 25 is therefore found with its axis of rotation oriented along a vertical direction and the forming drum 250 is located with its axis oriented along a horizontal direction.

Subsequently, the carriage 21 is moved along the movement direction A so as to pick up the forming drum 250 from the support member 45, in a similar way to what is illustrated in figure 10 (always meaning that instead of the forming drum 210 the forming drum 250 is present).

Subsequently, the carriage 21 with the forming drum 250 is moved along the movement direction B until it returns to its starting position P0 (or in the first working area W1 in the event that the starting position P0 is defined in the first area of work W1). During this movement, the forming drum 250 passes in a radially internal position with respect to the annular holding member 30 without stopping in the first service area S1, in the second work area W2 and in the first work area W1.

Just before, during or just after the movement of the trolley 21 to bring the forming drum 250 from the second service area S2 to the starting position P0 (or to the first working area W1 in case the starting position P0 is defined in the first work area W1), the drum transfer device 221, illustrated in figure 2, picks up the forming drum 25 from the support member 41 to send it to the path 230 of the crown structure packaging line 200 and onto the support member 41 is arranged, preferably again via the drum transfer device 221, a further substantially cylindrical forming drum, also entirely equivalent to the previously described forming drum 25, in the case in which it is desired to implement a cylindrical shape of a new pack belts, or a substantially toroidal forming drum, such as for example the forming drum 210, 210?, illustrated in figures 3-17, in case it is desired to implement a toroidal shape of the belt package.

The present invention ? been described with reference to some preferred embodiments. Various modifications can be made to the embodiments described above, remaining in any case within the scope of protection of the invention, defined by the following claims.

Claims (15)

1. Method of making vehicle wheel tire belt packs, including: - making a crossed belt structure (8) on a first substantially cylindrical forming drum (25); - choose, depending on the type of tire (2) to be produced, whether to make a belt pack (8?) of a cylindrical shape or a belt pack (8?) of a toroidal shape; wherein to manufacture a pack of belts (8?) of cylindrical shape said method comprises: - depositing at least one layer of belt at zero degrees (8c) on said first forming drum (25) in a radially external position with respect to said crossed belt structure (8); wherein to manufacture a belt pack (8?) of toroidal shape said method comprises: - withdrawing said crossed belt structure (8) from said first forming drum (25); - shaping said crossed belt structure (8) toroidally; - transferring said toroidally shaped crossed belt structure (8) onto a second forming drum (210); - depositing at least one layer of belt at zero degrees (8c) on said second forming drum (210) in a radially external position with respect to said toroidally shaped crossed belt structure (8). The method according to claim 1, wherein said cross belt structure (8) is packaged on said first substantially cylindrical forming drum (25) in a first working area (W1), said at least one zero degree belt layer (8c) ? deposited on said first forming drum (25) or on said second forming drum (210) in a second work area (W2) arranged downstream of said first work area (W1) with reference to a first movement direction ( A) and said crossed belt structure (8) ? toroidally shaped in a first service area (S1) arranged downstream of said second work area (W2) with reference to said first movement direction (A). 3. Method according to claim 2, wherein to manufacture a pack of belts (8?) of cylindrical shape said first forming drum (25) ? moved along said first movement direction (A) from said first work area (W1) to said second work area (W2) and from said second work area (W2) to a second service area (S2) arranged downstream of said first service area (S1) with reference to said first movement direction (A), wherein during movement from said second work area (W2) to said second service area (S2) the first forming drum ( 25) crosses said first service area (S1) without stopping there. 4. Method according to claim 2, wherein to manufacture a toroidal-shaped belt package (8?) said first forming drum (25)? moved along said first movement direction (A) from said first work area (W1) to said first service area (S1) crossing said second work area (W2) without stopping there. 5. Method according to claim 4, wherein to manufacture a belt package (8?) of toroidal shape said second forming drum (210) ? moved from said first service area (S1) to said second work area (W2) along a second movement direction (B) opposite to said first movement direction (A). 6. Method according to claim 5, wherein for making a belt pack (8?) of toroidal shape, after having moved said second forming drum (210) from said first service area (S1) to said second work area ( W2), said second forming drum (210) ? moved from said second work area (W2) along said first direction of movement (A) crossing said first service area (S1) without stopping there. 7. Method according to claim 5 or 6, wherein to manufacture a belt pack (8?) of toroidal shape, before moving said second forming drum (210) from said first service area (S1) to said second work (W2) said second forming drum (210) ? moved from a second service area (S2) to said first service area (S1) along said second feed direction (B), wherein said second service area (S2) ? arranged downstream of said first service area (S1) with reference to said first movement direction (A). The method according to any one of the preceding claims, wherein toroidally shaping said cross-belt structure (8) comprises: - transferring said crossed belt structure (8) from said first forming drum (25) to an annular retaining member (30). The method according to claim 8 when dependent on any one of claims 2 to 7, wherein said annular retaining member (30) is arranged in said first service area (S1). The method according to claim 9, wherein toroidally conforming said cross belt structure (8) comprises: - arranging said second forming drum (210) in a radially internal position to said annular retaining member (30). 11. Method according to claim 10, wherein toroidally shaping said crossed belt structure (8) comprises, after having arranged said second forming drum (210) in a radially internal position to said annular retaining member (30): - radially expanding said second forming drum (210) until it is in an expanded condition in which it is ? in contact with said crossed belt structure (8) and deforms said crossed belt structure (8) until they assume a toroidal shape. The method according to any one of claims 8 to 11, wherein transferring said cross belt structure (8) from said first forming drum (25) to said annular holding member (30) comprises: - arranging said first forming drum (25) in a radially internal position with respect to said annular retaining member (30). The method according to claim 12, wherein transferring said cross belt structure (8) from said first forming drum (25) to said annular holding member (30) comprises: - radially contracting said annular retaining member (30) until it comes into contact with said crossed belt structure (8). The method according to claim 13, wherein transferring said cross belt structure (8) from said first forming drum (25) to said annular retaining member (30) comprises, after radially contracting said annular retaining member (30 ): - radially contracting said first forming drum (25) leaving said crossed belt structure (8) under the load of said annular retaining member (30). The method according to any one of the preceding claims, wherein said second forming drum (210) is essentially toroidal.