WO2025141367A1 - Process and apparatus for applying functional inserts to tyres for vehicle wheels - Google Patents

Abstract

A functional insert (7) is applied to a tyre (2) such to fix an attachment surface (7a) of the insert by an attachment interface (G) interposed between the functional insert (7) and the tyre (2). The application provides for preforming the functional insert (7) in order to confer to the attachment surface (7a) a shaping that is substantially convex with the central zone (A) axially projecting with respect to the peripheral zone (B) along the central geometric axis (K). The central zone (A) is pressed against the radially inner surface (6) of the tyre (2), maintaining the peripheral zone (B) of the functional insert (7) spaced from the radially inner surface (6) by a retention action exerted along the peripheral zone (B). Subsequently, the peripheral zone (B) is pressed against the radially inner surface (6).

Description

"PROCESS AND APPARATUS FOR APPLYING FUNCTIONAL INSERTS TO TYRES FOR VEHICLE WHEELS"

The present invention relates to a process for applying functional inserts to tyres for vehicle wheels. The invention further relates to an apparatus for applying functional inserts to tyres for vehicle wheels.

A tyre for vehicle wheels typically has a substantially toroidal structure concentric with respect to a central rotation axis of the tyre itself during operation, and has a substantially concave inner surface, delimiting an inner cavity which, in operating conditions, is internally closed by a mounting rim. On the outer surface of the tyre, a tread band may be identified, integrated into a crown portion, and a pair of sidewalls which extend radially from respective axially opposite edges of the tread band towards respective beads adapted to engage with the mounting rim.

On some types of tyres it is known to incorporate functional inserts, typically applied against the inner surface after vulcanisation, for example to reduce noise, to monitor in real time the operating conditions of the tyre and track the temporal evolution of parameters representative of such operation.

In particular, functional inserts are known which are sensing devices fixed to the inner surface of a tyre to detect one or more physical quantities related to the operation of the tyre, such as temperature, internal pressure, acceleration of the inner surface, deformation of the inner surface, and more.

US 2023/0286235 Al describes an apparatus and process for applying a functional insert consisting of an elastomeric housing intended to accommodate an electronic sensor within a tyre. The elastomeric housing has a base wall having an attachment surface intended to mate with the inner surface of the tyre. A retaining wall projects from the base wall on the side opposite the attachment surface, to define a recess for the electronic sensor, in a central zone of the base wall itself.

For application purposes, a grip member carried by a robot picks up the functional insert to subject it to the distribution of an adhesive on the attachment surface and then apply it against the inner surface of the tyre. The grip member has an external pusher carrying at one end a grip chamber shaped according to the shape of the containment wall. A suction system flows into the grip chamber for retaining the functional insert at the containment wall. An inner pusher housed in the outer pusher is movable coaxially through the grip chamber, to act against the base wall of the functional insert, in an inner central zone with respect to the containment wall. The action of the inner pusher deforms the base wall in the central zone, causing it to project axially with respect to a peripheral zone thereof. With the movement of the grip member by the robot, the base wall comes into contact with its central zone against the radially inner surface of the tyre, shaping the base wall according to the curvature of the same radially inner surface. A subsequent sliding of the outer pusher with respect to the inner pusher causes the pressing of the circumferentially outer portion of the base wall against the radially inner surface of the tyre, while the robot commands an angular rotation of the entire grip member and of the functional insert, to uniformly distribute the glue in the attachment interface between the functional insert itself and the tyre.

The Applicant noted that the use of known devices such as the one described for example in US 2023/0286235 Al requires a certain structural consistency of the base wall of the functional insert, so that the latter does not undergo uncontrolled deformations during the fixing step.

However, in certain circumstances, for example in the processing of tyres intended for very high-performance motor vehicles or for sports competitions, it may be necessary to use functional inserts in which the base wall has a large surface area and/or a very limited thickness. The Applicant in fact deems it desirable to increase the surface extension of the attachment interface between the functional insert and the tyre, to improve the fixing resistance. At the same time, the Applicant deems it desirable to reduce the mass of the functional inserts and their parts as much as possible, since the inertia and consequent forces generated in the attachment interface between the functional insert and the tyre depend on the amount of such mass, due to the significant accelerations imposed during the rotation of the tyre at high speed.

However, reducing the thickness and/or increasing the surface area tends to reduce the structural consistency of the base wall, and consequently the possibility of exercising adequate control over the uniformity of adhesion against the inner surface of the tyre, a control that is of considerable importance when using specific adhesives, such as the PSA (Pressure Sensitive Adhesive) type, which do not allow for movement and/or repositioning of the functional insert during fixing, and for the effectiveness of which it is particularly important to avoid, among other things, accidental inclusions of air between the adhesion surface and the inner surface of the tyre.

The Applicant perceived that by controlling the entire geometry of the functional insert by shaping a part thereof, the above drawbacks are avoided since the uniformity of adhesion is effectively controlled.

More specifically, the Applicant found that it is possible to facilitate better control of the shape assumed by the functional insert itself during the fixing process by retaining the functional insert in proximity to the periphery of its base portion. This increases the quality and reliability of the coupling obtained between the functional insert and the tyre.

According to a first aspect, the invention relates to a process for applying functional inserts to tyres for vehicle wheels.

Preferably, provision is made for arranging a moulded and vulcanised tyre being processed having a radially inner surface. Preferably, provision is made for arranging a functional insert comprising a base portion having an attachment surface and an exposed surface directed opposite the attachment surface, and a containment portion projecting from the exposed surface concentric with a central geometric axis crossing through the attachment surface and the exposed surface.

Preferably, the base portion has a central zone crossed by said central geometric axis and a peripheral zone circumscribing the containment portion.

Preferably, provision is made for applying the functional insert to the tyre such to fix the attachment surface to said radially inner surface by an attachment interface interposed between the functional insert and the tyre.

Preferably, applying the functional insert to the tyre comprises preforming the functional insert in order to confer to the attachment surface a shaping that is substantially convex with the central zone axially projecting with respect to the peripheral zone along the central geometric axis.

Preferably, applying the functional insert to the tyre comprises pressing the central zone against the radially inner surface of the tyre, maintaining the peripheral zone of the functional insert spaced from the radially inner surface by a retention action exerted along the peripheral zone.

Preferably, provision is then made to interrupt the retention action in order to release the peripheral zone.

In a further aspect, the invention relates to an apparatus for applying functional inserts to tyres for vehicle wheels.

A transfer unit carrying a grip member is preferably provided. Preferably, the grip member comprises a pusher.

Preferably, the grip member comprises a thrust collar coaxially circumscribing the pusher.

Preferably, the grip member comprises a preforming actuator operating between the thrust collar and the pusher, in order to axially move the pusher with respect to the thrust collar along a thrust direction.

Preferably, the grip member has a grip surface having a central recess and a peripheral crown circumscribing the central recess and substantially normal with respect to the thrust direction.

Preferably, said peripheral crown has retention members distributed around the central recess.

Preferably, the retention members are selectively activatable in cooperation with the preforming actuator.

Preferably, the retention members are selectively activatable to retain a functional insert at a peripheral zone thereof, while the pusher is moved along the thrust direction to preform the functional insert.

Preferably, the functional insert is preformed according to a substantially convex shape.

Preferably, the functional insert is preformed with a central zone projecting axially with respect to the peripheral zone along a central geometric axis thereof.

The Applicant believes that the retaining action exerted along the peripheral zone facilitates the handling and correct application of functional inserts having a base portion of high surface extension and reduced structural consistency, irrespective of its geometric conformation. The application is also facilitated, but not only, when PSA or other types of attachment interfaces are used, that do not allow or make problematic repositioning and/or the presence of sliding between the functional insert and the inner surface of the tyre during the application.

In at least one convenient embodiment, the invention further comprises one or more of the following preferential features. Preferably, the interruption of the retention action is performed before an application of the peripheral zone against the inner surface of the tyre.

Preferably, the interruption of the retention action is achieved in the absence of contact between the peripheral portion and the inner surface of the tyre.

Preferably, preforming the functional insert comprises elastically deforming the functional insert.

Preferably, preforming the functional insert comprises elastically deforming the peripheral zone.

Preferably, the peripheral zone approaches the radially inner surface following the interruption of the retention action.

Preferably, preforming the functional insert comprises an axial displacement of the central zone with respect to the peripheral zone.

Preferably, the action of retaining the peripheral zone during the axial movement of the central zone is further provided.

Preferably, preforming the functional insert comprises an axial displacement of the containment portion relative to the peripheral zone.

Preferably, the action of retaining the peripheral zone during the axial movement of the containment portion is also provided.

Preferably, the retention action is achieved by a suction action exerted at the exposed surface.

Preferably, the retention action is achieved by means of a suction action exerted on the peripheral zone in a radially outer position with respect to the containment portion.

Preferably, the preforming action confers, to the attachment surface of the functional insert, a curvature greater than a curvature detectable on the radially inner surface of the tyre in an application zone of the functional insert.

Preferably, the preforming action is performed before the functional insert comes into contact with the radially inner surface of the tyre.

Preferably, the preforming action is actuated by exerting, on the central zone, a preforming thrust not smaller than a pressing thrust exerted for pressing of the same central zone against the radially inner surface of the tyre.

Preferably, the preforming action is actuated by means of a preforming actuator configured for exerting, on the central zone, a preforming thrust not smaller than a pressing thrust exerted for pressing of the same central zone against the radially inner surface of the tyre.

Preferably, the pressing thrust is comprised between 85% and 95% of the preforming thrust.

Preferably, the pressing of the central zone occurs with a pressing thrust no greater than the thrust action exerted for pressing the peripheral zone.

Preferably, the pressing force exerted during pressing of the central zone is between 85% and 95% of the pressing force exerted for pressing of the peripheral zone.

Preferably, applying the functional insert to the tyre comprises providing a grip member configured for retaining said functional insert.

Preferably, applying the functional insert to the tyre comprises arranging on a transfer unit a contrast member and at least one thrust actuator operating between said grip member and contrast member.

Preferably, applying the functional insert to the tyre comprises pushing said grip member and contrast member towards each other by said thrust actuator, in order to press the functional insert and said radially inner surface of the tyre against each other with mutually equal and opposite forces.

Preferably, said mutually equal and opposite forces balance out each other substantially without transmitting any stress to the transfer unit.

Preferably, during the action of pushing, the grip member and the contrast member are thrust towards each other by a single thrust actuator operating therebetween.

Preferably, provision is also made for the action of picking up the functional insert from a loading station by the grip member, and transferring it to a tyre being processed in an application station, before applying the functional insert to the tyre.

Preferably, the attachment interface is arranged on the attachment surface prior to retaining the functional insert by the grip member.

Preferably, the attachment interface is arranged on the attachment surface before removing the functional insert from the loading station.

Preferably, before reaching the application station, the functional insert picked up from the loading station is subjected to an application and/or activation of the attachment interface on the attachment surface thereof.

Preferably, before reaching the application station, the functional insert picked up from the loading station is subjected to an activation of an attachment interface on an attachment surface thereof.

Preferably, the action of angularly orienting the grip member around an angular orientation axis is also provided.

Preferably, the grip member is angularly rotated around the angular orientation axis, between an application condition in which a grip surface of the grip member faces in frontal alignment with respect to the contrast member, and a grip condition in which the grip surface faces away from the contrast member.

Preferably, the grip member in the loading station is oriented in the grip condition, to pick up the functional insert from the loading station.

Preferably, in the application station, the grip member is oriented in the application condition, in order to apply the functional insert against the radially inner surface of the tyre being processed.

Preferably, the grip member is oriented in the grip condition during a transfer toward the loading station.

Preferably, the grip member is oriented in the application condition during a transfer toward the application station.

Preferably, provision is also made to position the contrast member against the outer surface of the tyre before pressing the central zone against the radially inner surface of the tyre. Preferably, positioning the contrast member comprises translating the contrast member from a rest position towards a work position, and blocking the contrast member against the outer surface of the tyre.

Preferably, the blocking of the contrast member is driven in response to a detection of a thrust force on the contrast member itself.

Preferably, said thrust force has a value not exceeding 100 N. Preferably, the action of rotatably orienting the grip member in the grip condition, around a rotational orientation axis thereof that is normal and concentric with respect to the grip surface, is also provided.

Preferably, the following action is also provided: detecting an orientation of the functional insert; actuating said action of rotatably orienting the grip member based on the detected orientation of the functional insert.

Preferably, the orientation of the functional insert is detected around a central geometric axis thereof.

Preferably, the action of rotatably orienting the grip member around the rotational orientation axis is performed before picking up the functional insert.

Preferably, during the action of rotatably orienting the grip member around said rotational orientation axis, the contrast member rotates integral with the grip member.

Preferably, the action of rotatably orienting the grip member is performed by a rotary actuator carried by a terminal section of the transfer unit.

Preferably, said retention members comprise one or more suction openings distributed around the central recess and pneumatically activatable.

Preferably, the retention members are radially spaced from the central recess.

Preferably, the peripheral crown is configured for acting against said peripheral zone of a base portion of said functional insert. Preferably, the central recess is arranged to accommodate a containment portion projecting from a base portion of the functional insert.

Preferably, the suction openings are oriented along axes parallel to the thrust direction.

Preferably, the preforming actuator comprises a plunger movable along the thrust direction in a pressurisation chamber that is integral with respect to the thrust collar, in order to move the pusher with respect to the thrust collar, between an active position and a waiting position.

Preferably, in the active position, an active end of the pusher axially projects with respect to the grip surface, at the central recess.

Preferably, in the waiting position, an active end of the pusher is placed flush with the grip surface.

Preferably, in the waiting position one active end of the pusher is retracted into the thrust collar.

Preferably, said transfer unit carries a handling device comprising said grip member.

Preferably, the handling device comprises a support bracket engaged with the transfer unit and carrying the grip member.

Preferably, the handling device comprises at least one thrust actuator operating between the support bracket and the grip member.

Preferably, the thrust actuator operates on the thrust collar.

Preferably, the preforming actuator is configured for exerting a preforming thrust not smaller than a pressing thrust exerted by the thrust actuator.

Alternatively, the preforming actuator is configured for exerting a preforming thrust not greater than a pressing thrust exerted by the thrust actuator.

Preferably, a pressing thrust exerted by the thrust actuator is comprised between 85% and 95% of a preforming thrust exerted by the preforming actuator.

Alternatively, a preforming thrust exerted by the preforming actuator is between 85% and 95% of a pressing thrust exerted by the thrust actuator. Preferably, the handling device further comprises a contrast member carried by the support bracket.

Preferably, said thrust actuator is configured for pushing said grip member and contrast member towards each other, with mutually equal and opposite forces.

Preferably, the thrust actuator has a proximal end portion constrained to the support bracket, and a distal end portion carrying the grip member.

Preferably, the thrust actuator comprises a first fluid-dynamic cylinder and a second fluid-dynamic cylinder.

Preferably, the first fluid-dynamic cylinder and the second fluiddynamic cylinder are operatively connected in series with each other.

Preferably, the first fluid-dynamic cylinder has a fixed part carrying the proximal end portion and a movable part connected to a fixed part of the second fluid-dynamic cylinder, a movable part of which carries the distal end portion.

Preferably, the support bracket has a substantially U-shaped shape.

Preferably, the support bracket has a first arm carrying the grip member and a second arm carrying the contrast member, mutually interconnected by a connection arm perpendicular with respect thereto.

Preferably, the first and second arms extend substantially in a vertical direction downwards from the horizontally arranged connection arm.

Preferably, the proximal end portion of the thrust actuator is constrained to the first arm of the support bracket.

Preferably, at least one of said grip member and contrast member is slidably engaged with respect to the support bracket.

Preferably, at least one of said grip member and contrast member is slidably engaged with the support bracket along a direction parallel to the connection arm.

Preferably, the second arm of the support bracket is slidably engaged along the connection arm.

Preferably, a positioning actuator operates between the support bracket and the contrast member in order to move the latter between a rest position in which it is moved away from the grip member and a work position in which it is approached with respect to the grip member.

Preferably, the positioning actuator operates between the connection arm and the second arm.

Preferably, a block brake is also provided, operating on a movable part of the positioning actuator and selectively activatable in order to block the contrast member with respect to the support bracket.

Preferably, the block brake is activatable upon command of a tactile sensor associated with the contrast member, in response to a thrust force detected on the contrast member itself.

Preferably, the tactile sensor comprises a load cell or microswitch operating on the second arm.

Preferably, said thrust force has a value not exceeding 100 N. Preferably, the transfer unit comprises a robotic arm.

Preferably, the transfer unit is configured for alternatively translating the handling device between a loading station carrying a plurality of functional inserts and an application station carrying tyre being processed. Preferably, a treatment station is provided, operationally interposed between the loading station and the application station.

Preferably, the treatment station is configured for applying or activating an attachment interface on the application surface of a functional insert carried by the grip member.

Preferably, the grip member is angularly orientable with respect to the support bracket about an angular orientation axis.

Preferably, the grip member is angularly orientable between an application condition in which a grip surface of the grip member faces in frontal alignment with respect to the contrast member, and a grip condition in which the grip surface faces away from the contrast member.

Preferably, in the application condition, said grip surface and the contrast member are aligned along a horizontal direction.

Preferably, in the grip condition, the grip surface faces downwards.

Preferably, the proximal end portion of the thrust actuator is attached to a rotatable block engaged through the first arm of the support bracket.

Preferably, an orientation actuator is also provided, operating between the support bracket and the rotatable block in order to rotate the grip member together with the thrust actuator, between the application condition and the grip condition.

Preferably, the transfer unit carries the handling device by means of a terminal section rotatable around a rotational orientation axis.

Preferably, the rotational orientation axis is concentric with the grip surface when the grip member is in said grip condition.

Further features and advantages will become more apparent from the detailed description of preferred but non-exclusive embodiments of a process and related apparatus for applying functional inserts to tyres for vehicle wheels according to the present invention. Such description is given hereinafter with reference to the accompanying drawings, provided only for illustrative and, therefore, non-limiting purposes, in which:

Figure 1 shows a schematic plan view of a portion of a production line integrating an apparatus according to the invention;

Figure 2 shows a front and partial section view of a handling device of the subject apparatus, during the removal of a functional insert in a loading station;

Figure 3 shows the handling device of Figure 2, moved away from the loading station and with its own grip member seen from the front in an application condition; Figure 4 shows the handling device partially inserted into a tyre being processed, arranged in an application station;

Figure 5 shows the handling device of Figure 4 with a contrast member positioned against the tread of the tyre being processed;

Figure 6 schematically shows the handling device during the execution of a pressing thrust for the purpose of applying the functional insert against an inner surface of the tyre being processed;

Figure 7 shows on an enlarged scale and in greater detail a part of the handling device during the approach of a grip member to a radially inner surface of the tyre being processed;

Figure 8 shows the detail of Figure 7 during the pressing of a central area of the functional insert against the radially inner surface of the tyre being processed;

Figure 9 shows the detail of Figures 7 and 8 during the release of a peripheral zone of the functional insert towards the radially inner surface of the tyre being processed;

Figure 9a shows the detail of Figures 7 and 8 according to a possible embodiment, during the pressing of the peripheral zone of the functional insert against the radially inner surface of the tyre being processed;

Figure 10 shows a radial half-section of a tyre provided with a functional insert applied against a radially inner surface thereof;

Figure 11 shows a side view of a functional insert applicable according to the present invention.

With reference to the above figures, reference numeral 1 indicates as a whole an apparatus for applying functional inserts to tyres for vehicle wheels, according to the present invention.

Figures 4 to 6 and 10 schematically illustrate a tyre 2 for vehicle wheels which may be obtained using the subject process and apparatus. Along radially inner edges of the tyre 2, two beads 3 may be identified, through which the tyre 2 itself is usually engaged with a respective mounting rim (not shown).

Two sidewalls 4 each extend radially away from one of the beads 3, each joining a corresponding axially outer edge of a tread band 5 arranged in a radially outer position with respect to a central rotation axis X of the tyre 2. Contact between the road surface and the tyre 2 occurs at the tread band 5 during use. Overall, the tyre 2 has a substantially concave shape, defining an inner cavity delimited between a radially inner surface 6 of the tyre 2 and the aforementioned mounting rim. The tyre 2 may also comprise additional elements depending on the intended use. In this specific case, at least one functional insert 7 is provided, for example comprising a sensor 8 incorporated in an elastomeric housing 9 fixed against the radially inner surface 6 of the tyre 2 (Figures 10 and 11). In the illustrated example, the functional insert 7 is fixed in an axially centred position with respect to an axial centreline plane of the tyre 2, equidistant from the axially opposite edges of the tread band 5.

As better visible in Figure 11, the elastomeric housing 9 of the functional insert 7 comprises a base portion 9a having an attachment surface 7a and an exposed surface 7b, facing respectively opposite sides. From the exposed surface 7b of the base portion 9a, a containment portion 9b projects, concentric to a central geometric axis K which passes orthogonally through the attachment surface 7a. The containment portion 9b houses the sensor 8. In the base portion 9a there are a central zone A crossed by the central geometric axis K and a peripheral zone B circumscribing the containment portion 9b. More specifically, the peripheral zone B extends radially away from the containment portion 9b, starting from an outer perimeter edge of the latter.

Preferably, the functional insert 7 is fixed with the attachment surface 7a thereof against the radially inner surface 6 of the tyre 2, so that the exposed surface 7b faces a central rotation axis X of the tyre 2.

The apparatus 1 operates along a treatment line 10, only partially illustrated as it is not very relevant for the purposes of the invention, operationally arranged downstream of a vulcanisation station where the previously built tyres 2 are subjected to a moulding and vulcanisation treatment which stabilises the geometric structure thereof and the functional interaction of the various components.

The moulded and vulcanised tyres 2 moved along the treatment line 10 individually reach an application station 11 where each of them is subjected to the application of at least one functional insert 7. Preferably, the tyres 2 which travel along the treatment line 10 and/or reach the application station 11 are each oriented with their own central rotation axis X vertically arranged, with one of the sides 4 against one or more supports 12 defining a horizontal support plane P.

A positioning and centring device, not illustrated as it may be made in any convenient manner, may be provided at the application station 11 for placing the tyre 2 being processed according to a predetermined positioning, for example centred with respect to a fixed reference.

In a loading station 13 arranged in proximity to the application station 11, a plurality of functional inserts 7 may be arranged, positioned for example in one or more trays 14 used for their storage and transport.

Between the loading station 13 and the application station 11, a handling assembly 15 is arranged which, at each work cycle, is adapted to pick up at least one of the functional inserts 7 from the loading station 13, to transfer it to the tyre 2 being processed, arranged in the application station 11.

In a preferred embodiment, the handling assembly 15 comprises a transfer unit 16 carrying a handling device 17. In the illustrated example, the transfer unit 16 is made in the form of a robotic arm, preferably of the six-axis rotational movement type. In other embodiments, the transfer unit 16 may have a different number of movement axes, of the rotational and/or linear type.

Preferably, the handling device 17 is fixed to a terminal section 18 of the transfer unit 16, incorporating a rotary actuator 19 which allows the entire handling device 17 to be rotated about a rotational orientation axis Y.

The handling device 17 comprises a grip member 20 and a contrast member 21 carried by a support bracket 22, which in turn is engaged with the terminal section 18 of the transfer unit 16. The support bracket 22 may conveniently have a substantially inverted U or bridge shape, with a first arm 23 carrying the grip member 20 and a second arm 24 carrying the contrast member 21, arranged parallel to each other and interconnected by a connection arm 25 perpendicular with respect to them. In operating condition, the first arm 23 and the second arm 24 extend substantially in a vertical direction downwards from the horizontally arranged connection arm 25. As better illustrated in Figures 7 to 9, the grip member 20 may be made in the form of a shaped block, having a grip surface 20a having a shape consistent with the shape of the functional insert 7. More specifically, the grip surface 20a has a peripheral crown 26 carried by a thrust collar 50, circumscribing a central recess 27 arranged in proximity to an active end of a pusher 51. The pusher 51 is coaxially circumscribed by the thrust collar 50 and axially slidable with respect to the latter, along a longitudinal axis thereof defining a thrust direction S substantially normal with respect to the peripheral crown 26. The peripheral crown 26 is configured for coupling in abutment relation and act against the exposed surface 7b of the functional insert 7, at the peripheral zone B of the base portion 9a. The central recess 27 is configured for accommodating the containment portion 9b of the functional insert.

Between the thrust collar 50 and the pusher 51 operates a preforming actuator 52, configured for axially moving the pusher 51 along the thrust direction S. The preforming actuator 52 may for example comprise a piston 53 axially connected to the pusher 51 and movable along the thrust direction S in a pressurisation chamber 54 integral with the thrust collar 50. The introduction of a working fluid into the pressurisation chamber 54, respectively from one side or the other of the piston 53, causes the movement of the pusher 51 with respect to the thrust collar 50, between an active position and a waiting position. In the active position, the active end of the pusher 51 projects axially by a predetermined extent with respect to the grip surface 20a, at the central recess 27. In the waiting position, the active end of the pusher 51 may be positioned flush with the grip surface 20a, or retracted within the thrust collar 50.

As better visible in Figure 3 and in Figures 7 to 9, the grip surface 20a has retention members, preferably made in the form of one or more suction openings 28 distributed on the peripheral crown 26, around the central recess 27. The suction openings 28, preferably oriented along axes parallel to the thrust direction S, may be activated pneumatically through a suction circuit (not illustrated) flowing into a suction chamber 55 provided in the thrust collar 50, to retain the functional insert 7 against the grip surface 20a, at the peripheral zone B. In a possible embodiment variant not illustrated, the suction openings 28 may be replaced or assisted by hook elements or other mechanical members.

The grip member 20 is connected to the support bracket 22 by means of a thrust actuator 29 having a proximal end portion 29a constrained to the first arm 23, and a distal end portion 29b carrying the grip member 20 (Figure 6). As better visible in Figure 2, the thrust actuator 29 preferably comprises a first fluid-dynamic cylinder 30 and a second fluid-dynamic cylinder 31. The first fluid-dynamic cylinder 30 has a fixed part 30a carrying the proximal end portion 29a, and a movable part 30b connected to a fixed part 31a of the second fluid-dynamic cylinder 31, a movable part 31b of which carries the distal end portion 29b connected to the grip member 20. In other words, the first fluid-dynamic cylinder 30 and the second fluid-dynamic cylinder 31 are operationally connected in series with each other and may be activated in mutual cooperation between a retracted condition and an extended condition to move the grip member 20 along the thrust direction parallel to the connection arm 25. This construction configuration allows the thrust actuator 29 to have a long working stroke between the retracted condition and the extended condition, with a convenient containment of the overall longitudinal dimensions in the retracted condition. It is therefore possible to have a thrust actuator 29 that is sufficiently compact to also access the inside of tyres 2 having a reduced fit in the absence of mechanical interference, and with a sufficiently long operating stroke to allow the grip member 20 to reach the radially inner surface 6 of the tyre 2 even when the sidewalls 4 have a significant radial dimension.

It is conveniently provided that the thrust actuator 29 is rotatably engaged with respect to the support bracket 22, so that the grip member 20 is angularly orientable around an angular orientation axis Z, perpendicular to the direction of movement between the retracted condition and the extended condition. More in particular, the proximal end portion 29a of the thrust actuator 29 is attached to a rotatable block engaged through the first arm of the support bracket. An orientation actuator 33 operates between the support bracket 22 and the rotatable block 32 to rotate the grip member 20 together with the thrust actuator 29, between an application condition (Figures 4-6) in which the grip surface 20a faces in frontal alignment with respect to the contrast member 21, in a direction parallel to the connection arm 25 and preferably horizontal, and a grip condition (Figure 2) in which the grip surface 20a faces away from the contrast member 21, preferably downwards in a vertical direction and/or perpendicular to the connection arm 25.

Preferably, in the grip condition the rotational orientation axis Y of the entire handling device 17 is normal and concentric with respect to the grip surface 20a. At least one of said grip member 20 and contrast member 21 is slidably engaged with respect to the support bracket 22 along a direction parallel to the connection arm 25. For example, it may be provided for this purpose that the second arm 24 carrying the contrast member 21 is slidably engaged along the connection arm 25. A positioning actuator 34 operates between the connection arm 25 and the second arm 24, to translate the contrast member 21 between a rest position and a working position, in which it is moved away from and brought closer to the first arm 23, respectively. More specifically, the positioning actuator 34 operates between the connection arm 25 and the second arm 24. A blocking brake 35 operating on a movable part of the positioning actuator 34 is selectively activatable in order to block the contrast member 21 with respect to the support bracket 22. The activation of the blocking brake 35 may be carried out upon command of a tactile sensor 36 associated with the contrast member 21, for example in the form of a load cell or microswitch operating on the second arm 24, when a thrust force preferably not exceeding 100 N is detected on the contrast member 21 itself. It is therefore possible to facilitate the correct positioning of the contrast member 21 against the tread band 5 or another portion of the outer surface of the tyre 2, regardless of its diameter dimensions, to the advantage of operational flexibility, without transmitting significant stresses to said tyre 2.

The operating cycle envisaged for the application of a functional insert 7 according to the present invention provides that the handling device 17, once a previous operating cycle has been completed in the vicinity of the application station 11, is moved towards the loading station 13 upon command of the transfer unit 16.

In conjunction with the transfer to the application station 11, the orientation actuator 33 may be activated so that the grip member 20 is oriented from the application condition to the grip condition. As shown in Figure 2, with controlled movements on the various movement axes of the transfer unit

16, the grip member 20 that reaches the loading station 13 is positioned with its grip surface 20a facing downwards and in a centred position with respect to one of the functional inserts 7 to be applied to the next tyre 2 being processed, which has been prepared in the meantime in the application station 11.

By means of the transfer unit 16, optionally supported by an actuation of the thrust actuator 29, the grip member 20 is lowered vertically towards the functional insert 7, until its grip surface 20a is brought against the exposed surface 7b of the functional insert 7.

The suction action produced through the suction openings 28 causes the functional insert 7 to be retained against the grip surface 20a. In this approach and grip step, the preforming actuator 52 preferably keeps the pusher 51 in the waiting position, so that the engagement of the functional insert 7 by the grip member 20 may be performed without inducing substantial deformations to the functional insert itself.

The functional insert 7 may then be picked up and removed from the loading station 13 together with the handling device

17, to be transferred to the application station 11 by the action of the transfer unit 16.

It may be provided that, for example with the aid of a computerised artificial vision system 37 mounted on the transfer unit 16 or operating in the loading station 13 (Figure 1), the functional insert 7 to be applied is scanned to detect an orientation thereof, for example around the central geometric axis K thereof. Based on the data acquired through this detection operation, the rotary actuator 19 of the transfer unit 16 may command a rotation of the handling device 17, and therefore of the grip member 20 together with the contrast member 21 around the rotational orientation axis Y, before the engagement of the functional insert 7 by the grip member 20. This operation allows for the more precise positioning of functional inserts 7 containing particular sensors or other devices which, for correct functional interaction with the tyre 2, require a pre-established orientation with respect to, for example, a rolling direction of the tyre itself during use. The concentric positioning between the rotational orientation axis Y of the handling device 17 and the grip surface 20a allows the rotary actuator 19 of the transfer unit 16 to be used to orient the functional insert 7 around its central geometric axis K, without having to activate other movement axes of the transfer unit itself to keep the grip surface 20a centred with respect to the functional insert 7, to the advantage of simplifying programming and manoeuvring.

It may be provided that, before reaching the application station 11, the handling device 17 passes through a treatment station 38, where the application or activation of an attachment interface G on the attachment surface 7a of the functional insert 7 retained by the grip member 20 is performed. In a possible embodiment, the attachment interface G, for example of the PSA type, may already be present on the attachment surface 7a of the functional insert 7 provided in the loading station 13. In this case, the treatment station 38 may be configured for performing an attachment interface G activation treatment, which may for example comprise the removal of a protective film and/or the application of certain chemical reagents.

During the transfer to the application station 11, a new actuation of the orientation actuator 33 causes the grip member 20 to rotate around the angular orientation axis Z, causing it to assume the application condition upon reaching the application station 11.

At the application station 11, the handling device 17 is brought close to the tyre 2 being processed along a direction parallel to the central rotation axis X, until the grip member 20 carrying the functional insert 7 is inserted in a position axially interposed between the beads 3 of the tyre 2, as exemplified in Figure 4. At the same time, the contrast member 21, located in its rest position at the end of the connection arm 25, is positioned radially externally to the tread band 5 of the tyre 2. An activation of the positioning actuator 34 causes the contrast member 21 to move from the rest position towards the working position, until it meets the tread band 5 of the tyre 2, as shown in Figure 5. The tactile sensor 36 detects the contact of the contrast member 21 against the tread band 5 and controls the operation of the blocking brake 35, with consequent locking of the contrast member 21 in the working position against the tread band 5.

As shown in Figure 6, upon action of the thrust actuator 29, the functional insert 7, engaged by the grip member 20, is brought against the inner surface of the tyre 2 preferably in conjunction with or immediately after the positioning of the contrast member 21 in the working position.

As illustrated in Figure 7, before the functional insert 7 comes into contact with the radially inner surface of the tyre 2, an activation of the preforming actuator 52 causes the pusher 51 to move towards the active position. The action of the active end of the pusher 51 on the containment portion 9b of the functional insert 7 causes an axial displacement of the central zone A with respect to the peripheral zone B. In the meantime, the peripheral zone B remains subjected to the retaining action maintained on it through the suction openings 28.

As shown in Figures 7 and 8, due to the preforming effect, the functional insert 7 held by the grip member 20 is elastically deformed, so that the contact surface 7a takes on a substantially convex shape with the central zone A projecting axially with respect to the peripheral zone B along the central geometric axis K, in the direction of the tyre 2 being processed. More specifically, the contact surface 7a preferably assumes a greater curvature, i.e. it has a smaller radius of curvature, than that detectable on the radially inner surface 6 of the tyre 2, at least in the application zone of the functional insert 7. The convex shape assumed by the contact surface 7a may have a curvilinear cross-section profile or a substantially broken line, possibly with rounded corners. In the latter case, the curvature of the attachment surface 7a will be identifiable along an ideal arc tangent to the perimeter edges of the same and to the corners and/or relative connection zones identifiable along the broken line profile.

As illustrated in Figure 8, an initial contact between the functional insert 7 and the inner surface 6 of the tyre 2 therefore occurs at the central zone A of the functional insert 7, while the peripheral zone B remains spaced from the radially inner surface 6 due to the retaining action exerted on it. This circumstance favours the precision of positioning of the functional insert 7 with respect to the radially inner surface 6 of the tyre 2, and a correct expulsion of the air present, in proximity to the central zone A, between the same radially inner surface 6 and the attachment surface 7a and/or the attachment interface G arranged on it. When the functional insert 7 reaches the tyre 2, the action of the thrust actuator 29 causes the central zone A to be pressed against the radially inner surface of the tyre itself (Figure 8). Preferably, the preforming actuator 52 exerts a preforming thrust of an amount no less than, i.e. equal to or greater than, a pressing thrust exerted by the thrust actuator 29. In a preferred embodiment, the pressing thrust exerted by the thrust actuator 29 during pressing of the central zone A may be between 85% and 95% of the preforming thrust exerted by the preforming actuator 52 on the pusher 51. Within this range, the action of the thrust actuator 29 may be sufficient to produce, thanks to the mass inertia of the grip member 20 and the other elements integral with it, an initial impact useful for improving the adhesion of the central zone A against the radially inner surface 6, without pressing the peripheral zone B.

After the thrust actuator 29 has reached the extended condition, the pressing of the central zone A against the radially inner wall 6 occurs according to a force corresponding to the pressing thrust exerted by the thrust actuator 29 on the thrust collar 50, while the action of the preforming actuator 52 keeps the pusher 51 in the extracted position, counteracting its retreat towards the waiting position. Once the central zone A has reached the radially inner surface 6, the suction action through the suction openings 28 may be interrupted, thus releasing the peripheral zone B which may elastically return to its original shape, approaching the radially inner surface 6 until it eventually rests against it. More specifically, it is preferable that the peripheral zone B reaches the proximity of the radially inner surface 6 until it touches it without exerting substantial pressure. The final application of the peripheral zone B against the radially inner surface 6 may be entrusted to a subsequent pressing operation, carried out for example in the application station 11 or another work station, in order to perform an accurate control of the expulsion of the air present between the attachment interface G and the radially inner surface 6.

In a possible embodiment illustrated in Figure 9a, the preforming thrust applied by the preforming actuator 52 is no greater, i.e. equal to or less than, that exerted by the thrust actuator 29.

The pressing of the central zone A therefore occurs according to a force corresponding to the preforming thrust exerted by the preforming actuator 52, while the action of the thrust actuator 29 on the thrust collar 50 causes a progressive retraction of the pusher 51 towards the waiting position with respect to the thrust collar 50 itself. The thrust collar 50 continues to advance along the thrust direction S, progressively bringing the peripheral zone B of the base portion 9a closer to the tyre 2. When, as illustrated in Figure 9a, the peripheral zone B comes into contact with the tyre 6, the thrust collar 50 causes it to press against the radially inner surface itself, with a force corresponding to the action exerted by the thrust actuator 29, and the suction action through the suction openings 28 may therefore be interrupted.

In a preferred embodiment, the preforming thrust exerted by the preforming actuator 52 during the pressing of the central zone A may be between 85% and 95% of the pressing thrust exerted by the thrust actuator 29 for the pressing of the peripheral zone B.

Preferably, the thrust transmitted to the tyre 2 during pressing is counteracted by the counteracting member 21, locked with respect to the connecting arm 25. The action of the single thrust actuator 29 is conveniently expressed through the support bracket 22, between the grip member 20 and the contrast member 21 which are simultaneously pushed towards each other with mutually equal and opposite forces. The thrust exerted by the grip member 20 and the reaction force generated by the contrast member 21 balance each other out through the support bracket 22 without affecting the transfer unit 16 and without causing movements or deformations to/in the tyre 2. In other words, the functional insert 7 and the radially inner surface 6 of the tyre 2 are pressed against each other with mutually equal and opposite forces, which balance each other out without thereby transmitting significant forces to the transfer unit 16. It is therefore possible to exert high forces, even greater than 1000 N, to promote optimal and reliable adhesion of the functional insert 7 on the radially inner surface 6 of the tyre 2, without risking overstressing the parts that make up the transfer unit 16 and/or damaging/moving the tyre 2. Therefore, transfer units 16 may also be used in the form of a robotic arm, having dimensions, weight, costs and maintenance requirements lower than those that would be required to perform the application with high thrust forces using different devices.

Claims

1. Process for applying functional inserts to tyres for vehicle wheels, comprising: arranging a moulded and vulcanised tyre (2) being processed, having a radially inner surface (6); arranging a functional insert (7) comprising a base portion (9a) having an attachment surface (7a) and an exposed surface (7b) directed opposite the attachment surface (7a), and a containment portion (9b) projecting from the exposed surface (7b) concentric with a central geometric axis (K) crossing through the attachment surface (7a) and the exposed surface (7b), wherein the base portion (9a) has a central zone (A) crossed by said central geometric axis (K) and a peripheral zone (B) circumscribing the containment portion (9b); applying the functional insert (7) to the tyre (2) such to fix the attachment surface (7a) to said radially inner surface (6) by an attachment interface (G) interposed between the functional insert (7) and the tyre (2), wherein applying the functional insert (7) to the tyre (2) comprises: preforming the functional insert (7) in order to confer to the attachment surface (7a) a shaping that is substantially convex with the central zone (A) axially projecting with respect to the peripheral zone (B) along the central geometric axis (K), pressing the central zone (A) against the radially inner surface (6) of the tyre (2), maintaining the peripheral zone (B) of the functional insert (7) spaced from the radially inner surface (6) by a retention action exerted along the peripheral zone (B); subsequently, interrupting the retention action in order to release the peripheral zone (B).

2. Process according to claim 1, wherein preforming the functional insert (7) comprises elastically deforming the functional insert (7).

3. Process according to claim 1 or 2, wherein preforming the functional insert (7) comprises an axial movement of the central zone (A) with respect to the peripheral zone (B).

4. Process according to claim 3, also comprising the action of retaining the peripheral zone (B) during the axial movement of the central zone (A).

5. Process according to one or more of the preceding claims, wherein the retention action is actuated by a suction action exerted at the exposed surface (7b).

6. Process according to one or more of the preceding claims, wherein the preforming action confers, to the attachment surface (7a) of the functional insert (7), a curvature greater than a curvature detectable on the radially inner surface (6) of the tyre (2) in an application zone of the functional insert (7).

7. Process according to one or more of the preceding claims, wherein the preforming action is actuated before the functional insert (7) comes into contact with the radially inner surface (6) of the tyre (2).

8. Process according to one or more of the preceding claims, wherein the preforming action is actuated by exerting, on the central zone (A), a preforming thrust not smaller than a pressing thrust exerted for pressing of the same central zone (A) against the radially inner surface (6) of the tyre (2).

9. Process according to claim 8, wherein the pressing thrust is comprised between 85% and 95% of the preforming thrust.

10. Process according to one or more of the preceding claims, wherein said functional insert (7) is one from among: arranging a grip member (20) configured for retaining said functional insert (7); arranging, on a transfer unit (16), a contrast member (21) and at least one thrust actuator (29) operating between said grip member (20) and contrast member (21); pushing said grip member (20) and contrast member (21) towards each other by said thrust actuator (29), in order to press the functional insert (7) and said radially inner surface (6) of the tyre (2) against each other with mutually equal and opposite forces.

11. Apparatus for applying functional inserts a tyres for vehicle wheels, comprising: a transfer unit (16) carrying a grip member (20); wherein the grip member (20) comprises: a pusher (51); a thrust collar (50) coaxially circumscribing the pusher (51); a preforming actuator (52) operating between the thrust collar (50) and the pusher (51), in order to axially move the pusher (51) with respect to the thrust collar (50) along a thrust direction (S), wherein the grip member (20) has a grip surface (20a) having a central recess (27) and a peripheral crown (26) circumscribing the central recess (27) and substantially normal with respect to the thrust direction (S), wherein said peripheral crown (26) has retention members distributed around the central recess (27), selectively activatable in cooperation with the preforming actuator (52) in order to retain a functional insert (7) at a peripheral zone (B) thereof while the pusher (51) is moved along the thrust direction (S) in order to preform the functional insert (7) according to a substantially convex shaping, with a central zone (A) thereof projecting axially with respect to the peripheral zone (B) along a central geometric axis (K) thereof.

12. Apparatus according to claim 11, wherein said retention members comprise one or more suction openings (28) distributed around the central recess (27) and pneumatically activatable.

13. Apparatus according to claim 11 or 12, wherein the peripheral crown (26) is configured for acting against said peripheral zone (B) of a base portion (9a) of said functional insert (7).

14. Apparatus according to one or more claims from 11 to

13, wherein the central recess (27) is arranged for receiving a containment portion (9b) projecting from a base portion (9a) of the functional insert (7).

15. Apparatus according to one or more claims from 12 to

14, wherein the suction openings (28) are oriented according to axes parallel to the thrust direction (S).

16. Apparatus according to one or more claims from 11 to

15, wherein the preforming actuator (52) comprises a plunger (53) movable along the thrust direction (S) in a pressurisation chamber (54) that is integral with respect to the thrust collar (50), in order to move the pusher (51) with respect to the thrust collar (50), between an active position and a waiting position.

17. Apparatus according to claim 16, wherein in the active position, an active end of the pusher (51) axially projects with respect to the grip surface (20a), at the central recess (27).

18. Apparatus according to claim 16 or 17, wherein in the waiting position, an active end of the pusher (51) is placed flush with the grip surface (20a).

19. Apparatus according to one or more claims from 16 to

18, wherein in the waiting position, an active end of the pusher (51) is retracted within the thrust collar (50).

20. Apparatus according to one or more claims from 11 to

19, wherein said transfer unit (16) carries a handling device (17) comprising: said grip member (20); a support bracket (22) engaged with the transfer unit (16) and carrying the grip member (20); at least one thrust actuator (29) operating between the support bracket (22) and the grip member (20).

21. Apparatus according to claim 20, wherein the thrust actuator (29) operates on the thrust collar (50).

22. Apparatus according to claim 20 or 21, wherein the preforming actuator (52) is configured for exerting a preforming thrust not smaller than a pressing thrust exerted by the thrust actuator (29).

23. Apparatus according to one or more claims from 20 to

22, wherein a pressing thrust exerted by the thrust actuator (29) is comprised between 85% and 95% of a preforming thrust exerted by the preforming actuator (52).

24. Apparatus according to one or more claims from 20 to

23, wherein the handling device (17) also comprises a contrast member (21) carried by the support bracket (22).

25. Apparatus according to claim 24, wherein said thrust actuator (29) is configured for pushing said grip member (20) and contrast member (21) towards each other, with mutually equal and opposite forces.