Method and tire manufacturing station for terminating a continuous strip to form a tire component

Abstract

The invention relates to a method and a tire manufacturing station for terminating a continuous strip to form a tire component, wherein the method comprises the steps of: a) continuously extruding the continuous strip with an extruder, wherein the extruder comprises a die with a die opening for shaping the continuous strip; b) receiving the continuous strip from the extruder onto a supply member; c) moving an end retainer in a shearing direction across said die, wherein the end retainer comprises a cutting surface that cooperates with the die opening to shear cut the continuous strip at the die, thereby forming a trailing end of the tire component; d) pressing the trailing end with the end retainer in a pressing direction onto the supply member; and e) moving the end retainer together with the supply member in a supply direction while retaining the trailing end with the end retainer on the supply member along at least a part of a supply path.

Description

[0001] P143514PC00

[0002] Method and tire manufacturing station for terminating a continuous strip to form a tire component

[0003] BACKGROUND

[0004] The invention relates to a method and a tire manufacturing station for terminating a continuous strip to form a tire component .

[0005] Figures 9 and 10 show a conventional tire manufacturing station during steps of a known method for terminating a continuous strip to form a tire component . As shown in figure 9 , the conventional tire manufacturing station comprises an extruder for continuously extruding the continuous strip and an applicator roll for receiving the continuous strip from the extruder and for supplying the continuous strip further towards a drum. The conventional tire manufacturing station further comprises a pressing finger for retaining the continuous strip in a retaining position on the applicator roll . In particular, the pressing finger is moved towards the applicator roll at a distance from the extruder to deflect and press the length of the continuous strip between the extruder and the applicator roll towards and onto the applicator roll . The pressing finger is configured to subsequently follow the continuous strip in the retaining position on the applicator roll as the applicator roll rotates .

[0006] To terminate the continuous strip, the extruder is temporarily stopped while the applicator roll continues to rotate and while the continuous strip is retained on the applicator roll by the pressing finger . This cools down the continuous strip and creates a tension in the continuous strip as it cools and hardens , downstream of the extruder, until the hardened continuous strip ultimately snaps or breaks in an area between the extruder and the pressing finger .

[0007] SUMMARY OF THE INVENTION

[0008] A disadvantage of the known method is that the continuous strip, when it is being deflected by the pressing finger towards the applicator roll and / or when it snaps or breaks , is subj ected to considerable tension, causing stretched, irregular, inconsistent and / or disformed snapped ends which may lead to quality issues during the subsequent application of the continuous strip on the drum . Moreover, the pressing finger may leave imprints in the continuous strip at the retaining position as a result of the tension being generated in the continuous strip while the continuous strip is being retained by the pressing finger, thereby further reducing the quality of the tire component that is obtained after snapping or breaking off said tire component from the continuous strip . Additionally, temporarily stopping the extruder to allow the continuous strip to cool down and harden adds cycle time to the manufacturing process .

[0009] It is an obj ect of the present invention to provide a method and a tire manufacturing station for terminating a continuous strip to form a tire component, wherein quality issues in the tire component as a result of the termination of the continuous strip can be reduced and / or prevented .

[0010] According to a first aspect , the invention provides a method for terminating a continuous strip to form a tire component, wherein the method comprises the steps of : a) continuously extruding the continuous strip with an extruder, wherein the extruder comprises a die with a die opening for shaping the continuous strip ; b) receiving the continuous strip from the extruder onto a supply member, wherein the supply member is configured for supplying the continuous strip further in a supply direction along a supply path; c) moving an end retainer in a shearing direction across said die, wherein the end retainer comprises a cutting surface that cooperates with the die opening to shear cut the continuous strip at the die, thereby forming a trailing end of the tire component ; d) pressing the trailing end with the end retainer in a pressing direction onto the supply member; and e ) moving the end retainer together with the supply member in the supply direction while retaining the trailing end with the end retainer on the supply member along at least a part of the supply path .

[0011] By shear cutting the continuous strip directly at the die, the tension generated in the continuous strip prior to termination can be reduced signi ficantly, compared to the tension generated in the known method of the prior art . Consequently, a more cleanly cut and / or high quality trailing end and leading end can be formed . Moreover, as the shear cutting is performed by moving the end retainer across the die, the trailing end created by the cutting action of the end retainer can immediately thereafter be deflected towards and be pressed onto the supply member by the same end retainer . At this moment, the trailing end of the tire component is no longer connected to the continuous strip, and therefore the deflection and pressing can occur without introducing any significant further tension in the tire component . An additional advantage is that the end retainer can remain in close proximity to or in direct contact with the trailing end from the moment of cutting up to the pressing of said trailing end onto the support member, thereby allowing for a more controlled and / or accurate trans fer of said trailing end from the extruder to the support member . Moreover, as the continuous strip can be cut immediately without having to wait for the continuous strip to cool down and harden, the overall cycle time of the manufacturing process can be shortened .

[0012] In a preferred embodiment the shearing direction is perpendicular to the supply direction . Hence, the end retaining can be moved in said shearing direction perpendicular to the supply direction, to effectively terminate or cut-of f the continuous strip directly at the die .

[0013] In another preferred embodiment the pressing direction is the shearing direction . Hence, after cutting, the end retainer can continue its movement in the same direction .

[0014] In a further embodiment the end retainer continues to move linearly in the shearing direction after the shear cutting in step c) until the end retainer presses the trailing end onto the supply member in step d) . By moving the end retainer linearly, the end retainer can terminate the continuous strip and press the trailing end of the tire component onto the support member in a single motion .

[0015] In another embodiment the extruder continuously extrudes the continuous strip in step a) in an extrusion direction, wherein the die opening extends in a die plane perpendicular to the extrusion direction, wherein the cutting surface , in step c ) , is positioned to extend in a cutting plane parallel or substantially parallel to the die plane . The cutting surface can thus act as a guillotine kni fe or blade moving across the die opening to shear cut the continuous strip .

[0016] Preferably, the cutting surface still at least partially overlaps with the die opening during the pressing in step d) and prior to step e ) . The cutting surface can therefore also prevent that extrudate spills from the extruder during the actions of step d) and e ) .

[0017] Additionally or alternatively, the cutting plane , in step c) , extends at a die clearance from the die plane of less than three millimeters , preferably less than two millimeters and most preferably less than one millimeter . By minimizing the die clearance , i f possible to a zero die clearance , deformation of the continuous strip between the die and the end retainer as a result of the shear cutting can be reduced .

[0018] In another embodiment the supply member is an applicator roll with a roller body that is rotatable about a roll axis and that defines a retaining surface extending in a circumferential direction about the roll axis , wherein the end retainer is moved together with the supply member in step e ) along a retaining arc about the roll axis as the roller body rotates about said roll axis . Because the end retainer follows the continuous strip on the retaining surface as the roller body rotates , the continuous strip can be retained more securely to the applicator roller for at least a part of the rotation of the roller body . In particular, when initially suction openings in the roller body are not yet connected to a source of partial vacuum, the end retainer may already retain the continuous strip to the retaining surface until the respective suction openings are rotated into a position in which they are connected to a source of partial vacuum. The continuous strip can thus be retained by either the end retainer, the roller body or both, according to a principle of never letting go of said continuous strip .

[0019] Preferably, the retaining arc is at least ten degrees , preferably at least twenty degrees , and most preferably at least thirty degrees . The longer the retaining arc, the longer the continuous strip can be reliably retained to the roller body .

[0020] In another embodiment the method further comprises the step of : f ) separating the trailing end of the tire component from the end retainer after step e ) by retracting the end retainer in a retraction direction away from the supply member . The end retainer can therefore make room for the subsequent interaction between the supply member and a downstream element of the tire manufacturing station, for example a drum.

[0021] Preferably, the separation in step f ) is assisted by providing compressed air between the end retainer and the trailing end as the end retainer is retracted in the retraction direction . The compressed air can prevent that the trialing end of the tire component or the trialing end of the tire component or the leading end of the continuous strip remains stuck to the end retainer when said end retainer is moved away from the supply member at the end of the motion in step e ) .

[0022] In another embodiment the method further comprises the step of : g) returning the end retainer over a return distance in a return direction towards the extruder . After returning the end retainer over the return distance, one or more steps of the method can be repeated for further ends to be retained during subsequent cycles of the method . In particular, the same end retainer can be used for picking-up the leading end of the continuous strip that remained at the extruder after step c) , by performing steps d) and e ) for the leading end instead of the trailing end .

[0023] Preferably, the method further comprises the step of : h) adj usting the return distance prior to or during step g) by moving a stopper relative to the extruder, wherein the end retainer is moved in the return direction until the end retainer contacts the stopper in said return direction . Hence, the return distance can ef fectively be controlled and / or adj usted without modi fying the return mechanism itself . In particular, by adj usting the return distance, the end retainer can either be returned to a trailing end position in which the end retainer can be moved closely in front of the die to enable the shear cutting in step c) , or to a leading end position further downstream in the extrusion direction relative to the trailing end position, in which the end retainer can be press the leading end of the continuous strip, which proj ects from the die after step c) , onto the supply member without cutting of f the continuous strip at the die .

[0024] In another embodiment the extruder is configured for extruding the continuous strip at an extrusion speed and wherein the supply member is configured for supplying the continuous strip in the supply direction at a supply speed, wherein the method, between steps b) and c ) , comprises the step of generating a speed difference between the extrusion speed and the supply speed at which the supply speed is greater than the extrusion speed . As a result of the speed di fference, the continuous strip can be stretched prior to the shear cutting in step c) to reduce the cross-sectional area of the continuous strip at the location where the trailing end of the tire component is formed . Hence, a slightly tapered trailing end can be obtained that can be advantageous to minimize the surplus material when completing a strip-winding process with overlapping windings .

[0025] Preferably, the extrusion speed is decreased, reduced to zero or reversed to a negative value, and / or wherein the supply speed is increased . By decreasing the extrusion speed, a speed dif ference can be generated at which the supply speed is greater than the extrusion speed . By further reducing the extrusion speed to zero, it can be prevented that excessive extrudate escapes from the extruder during the shear cutting in step c ) . By reversing the extrusion speed to a negative value, the extrudate in the extruder can be sucked back slightly to even more reliably prevent that extrudate escapes from the extruder . Additionally or alternatively, the supply speed can be increased to generate a similar or even greater speed di fference .

[0026] According to a second aspect , the invention provides a tire manufacturing station for terminating a continuous strip to form a tire component, wherein the tire manufacturing station comprises an extruder for continuously extruding the continuous strip, wherein the extruder comprises a die with die opening for shaping the continuous strip, wherein the tire manufacturing station further comprises a supply member for receiving the continuous strip from the extruder and for supplying the continuous strip further in a supply direction along a supply path, wherein the tire manufacturing station further comprises an end retainer that is movable relative to the extruder in a shearing direction across the die, an end retainer drive for moving the end retainer and a control unit that is operationally connected to the end retainer drive for controlling movement of the end retainer, wherein the control unit is configured for : moving the end retainer in the shearing direction across the die, wherein the end retainer comprises a cutting surface that cooperates with the die opening to shear cut the continuous strip at the die , thereby forming a trailing end of the tire component ; moving the end retainer in a pressing direction towards the supply member to press the trailing end onto said supply member; and moving the end retainer together with the supply member in the supply direction while retaining the trailing end with the end retainer on the supply member along at least a part of the supply path .

[0027] The tire manufacturing station according to the second aspect of the invention has a control unit that is arranged, programmed and / or configured for performing the steps of the method according to the first aspect of the invention and therefore has the same technical advantages , which will not be repeated hereafter .

[0028] In a preferred embodiment the extruder is configured for continuously extruding the continuous strip in an extrusion direction, wherein the die opening extends in die plane perpendicular to the extrusion direction, wherein the cutting surface , during the shear cutting of the continuous strip, extends in a cutting plane parallel or substantially parallel to the die plane . The cutting surface can thus act as a guillotine knife or blade moving across the die opening to shear cut the continuous strip .

[0029] In a further embodiment the cutting plane , during the shear cutting of the continuous strip, extends at a die clearance from the die plane of less than three millimeters , preferably less than two millimeters and most preferably less than one millimeter . By minimi zing the die clearance , if possible to a zero die clearance , deformation of the continuous strip between the die and the end retainer as a result of the shear cutting can be reduced .

[0030] In another embodiment, the end retainer comprises a pressing surface facing in the pressing direction . Hence, in addition to shear cutting the continuous strip with the cutting surface, the end retainer can simultaneously press the tire component in the pressing direction towards and / or onto the supply member with the pressing surface .

[0031] Preferably, the pressing surface is rounded . Hence, the pressing surface can press the tire component onto the supply member at various angles to said supply member, which can be particularly convenient when the supply member has a round retaining surface, such as the retaining surface of the previously discussed applicator roll .

[0032] Additionally or alternatively, the end retainer comprises a blow-off section at the pressing surface, wherein the blow-of f section is provided with one or more blow-of f openings which are connectable to a source of compressed air . When connected to the source of compressed air, compressed air can be provided between the pressing surface and the tire component to prevent that the trialing end of the tire component or the leading end of the continuous strip remains stuck to the end retainer when said end retainer is moved away from the supply member at the end of the motion in step e ) .

[0033] In another embodiment the blow-off section comprises a porous structure , wherein the one or more blowof f openings are pores of the porous structure . The porous structure can more uniformly distribute the compressed air over the blow-off section compared to a single blow-of f opening or a limited number of relatively large blow-off openings . Moreover, the pores of the porous structure are so small that they are less likely to collect dust or other contaminants . Preferably, the porous structure is 3D printed or obtained through 3D printing . 3D printed porous structures may have shapes that are not possible with other porosity introducing manufacturing techniques , such as sintering . In particular, the 3D printed porous structure may be optimized to leave a minimum imprint on the continuous strip or the tire component during the pressing action of the end retainer . Moreover, by using 3D printing techniques , the porous structure can be integrally formed with the rest of the end retainer .

[0034] In another embodiment the control unit is further configured for returning the end retainer over a return distance in a return direction towards the extruder, wherein the tire manufacturing station comprises a stopper for stopping the end retainer after moving over the return distance in the return direction, wherein the stopper is movable relative to the extruder for adj usting the return distance . Hence, the return distance can effectively be controlled and / or adj usted without modi fying the return mechanism itsel f .

[0035] In another embodiment the supply member is an applicator roll with a roller body that is rotatable about a roll axis and that defines a retaining surface extending in a circumferential direction about the roll axis , wherein the control unit is configured for moving the end retainer together with the supply member along a retaining arc about the roll axis as the roller body rotates about said roll axis . Because the end retainer follows the continuous strip on the retaining surface as the roller body rotates , the continuous strip can be retained more securely to the applicator roller for at least a part of the rotation of the roller body .

[0036] The various aspects and features described and shown in the specification can be applied, individually, wherever possible . These individual aspects , in particular the aspects and features described in the attached dependent claims , can be made subj ect of divisional patent applications . Specifically, the end retainer and its features , such as the blow-of f section, can be applied independently of the tire manufacturing station .

[0037] BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The invention will be elucidated on the basis of an exemplary embodiment shown in the attached schematic drawings , in which : figures 1- 6 show side views of a tire manufacturing station according to the invention during steps of a method for terminating a continuous strip to form a tire component ; figures 7 and 8 show details , in side view and rear view, respectively, of an end retainer of the tire manufacturing station according to figure 5 ; and figure 9 and 10 show side views of a conventional tire manufacturing station according to the prior art .

[0039] DETAILED DESCRIPTION OF THE INVENTION

[0040] Figures 1- 6 show a tire manufacturing station 1 according to the invention . The tire manufacturing station 1 is used for terminating a continuous strip 90 to form a tire component 91 in a method according to the invention .

[0041] The tire component 91 can be used in subsequent manufacturing process to be build or assemble a green or unvulcani zed tire . In this particular example , the tire manufacturing station 1 comprises a drum 11 , in particular a strip-winding drum, for receiving the tire component 91 . The tire component 91 may be wound around the drum 11 over several revolutions to build an aggregate cross section of the green or unvulcani zed tire .

[0042] As shown in figure 1 , the tire manufacturing station 1 comprises an extruder 2 for continuously extruding the continuous strip 90 . The tire manufacturing station 1 comprises a frame or base 10 for holding the extruder 2 in position relative to the drum 11 . The continuous strip 90 is initially extruded in an extrusion direction E . The extruder 2 comprises a die 21 for shaping the continuous strip 90 . The die 21 defines a die opening 22 . In this example, the die opening 22 extends in a die plane Z1 perpendicular to the extrusion direction E . The die opening 22 is defined, bound or delimited by an edge 23 . The extruder 2 is configured for extruding the continuous strip 90 at an extrusion speed VI .

[0043] The tire manufacturing station 1 further comprises a supply member 3 for receiving the continuous strip 90 from the extruder 2 . The supply member 3 is configured for conveying or supplying the continuous strip 90 or the tire component 91 obtained from said continuous strip 90 further along a supply path P with at least a vector component in a supply direction S . The supply member 3 is configured for supplying the continuous strip 90 or the tire component 91 in the supply direction S and / or along the supply path P at a supply speed V2 . The tire manufacturing station 1 comprises a supply member drive 6 that is operationally connected to the supply member 3 for driving the conveyance or the supply in said supply direction S .

[0044] In this example, the supply member 3 is an applicator roll 4 for applying the continuous strip 90 or the tire component 91 obtained from said continuous strip 90 to the drum 11 . The applicator roll 4 comprises a roller body 40 that is rotatable about a roll axis X . The roller body 40 has or defines a retaining surface 41 extending in a circumferential direction C about the roll axis X .

[0045] Furthermore, in this example , the applicator roll 4 is provided with an inner member that is located concentrically within the roller body 40 . The roller body 40 is rotatable in the circumferential direction C about the inner member while the inner member remains stationary . The inner member comprises a first chamber 42 that is connected to a source of partial vacuum and a second chamber 43 that is connectable to a source of compressed air, for providing partial vacuum and compressed air to parts of the roller body 40 in specific circumferential sections about the roller axis

[0046] X .

[0047] For the purpose of the invention, the relevant functionality of the supply member 3 is that it supplies the continuous strip 90 or the tire component 91 further with at least a vector component in the supply direction S . Consequently, the applicator roll 4 may be replaced with another type of supply member, for example a conveyor (not shown) , moving in or parallel to the supply direction S .

[0048] As shown in figure 1 , the tire manufacturing station 1 further comprises a pressing finger, an end handler, an end manipulator or an end retainer 5. In this example, the end retainer 5 is suspended from or mounted to the same frame or base 10 that holds the extruder 2 . The end retainer 5 is used to press , handle, manipulate and / or retain a trailing end TE of the tire component 91 that is created when terminating the continuous strip 90 , as shown in figures 3 , 4 and 5. Additionally, the same end retainer 5 may optionally be used to press , handle, manipulate and / or retain a leading end LE of the continuous strip 90 that remains at the extruder 2 when the continuous strip 90 is terminated, as shown in figure 6. Alternatively, the tire manufacturing station 1 may be provided with a dedicated tool for handling the leading end LE of the continuous strip 90 . The present invention focusses on the handling of the trailing end TE of the tire component 91 .

[0049] The tire manufacturing station 1 further comprises an end retainer drive 7 for moving the end retainer 5 in a shearing direction DI , a pressing direction D2 , the supply direction S and / or a return direction Y . The end retainer drive 7 is configured for moving the end retainer 5 relative to the extruder 2 , the supply member 3 , the drum 11 and / or the base 10 holding one or more of the aforementioned parts of the tire manufacturing station 1 . In this example , the end retainer drive 7 comprises a shearing / pressing actuator 71 and a supply / return actuator 72 . The shearing / pressing actuator 71 controls the position of the end retainer 5 in the shearing direction DI and the pressing direction D2 . The supply / return actuator 72 controls the position of the end retainer 5 in the supply direction S and the return direction Y . In this example, the shearing direction DI and the pressing direction D2 are perpendicular or orthogonal to the supply direction S and the return direction Y . Hence, the shearing pressing actuator 71 and the supply / return actuator 72 may be configured to act as an orthogonal or XY-drive system. More in particular, in this example , the shearing / pressing actuator 71 and the supply / return actuator 72 are linear actuators , in particular pneumatic cylinders , that are configured to act on the end retainer 5 in the respective directions .

[0050] As shown in more detail in figure 7 , the end retainer 5 comprises a retainer body 50 . In this example, the retainer body 50 is made from metal , for example steel or aluminum.

[0051] The end retainer 5 comprises a cutting surface 51 for terminating the continuous strip 90 to form the tire component 91 . In this embodiment, the cutting surface 51 is formed or defined by the retainer body 50 . Alternatively, the cutting surface 51 may be formed by a kni fe-like element or knife attached or mounted to said retainer body 50 . In this example , the cutting surface 51 is planar or substantially planar . The end retainer 5 is positionable relative to the extruder 2 such that the cutting surface 51 extends in a cutting plane Z2 parallel or substantially parallel to the die plane Z l . In particular, in figure 1 , the end retainer 5 is moved into a trailing end position Pl in which the cutting plane Z2 extends at a minimum die clearance of less than one millimeter to the die plane Zl . I f possible , the die clearance is zero , such that the cutting plane Z2 and the die plane Zl are coplanar . Because of the minimal die clearance, the cutting plane Z2 and the die plane Zl are schematically shown in figure 1 as a single plane Z1»Z2 .

[0052] As further shown in figure 7 , the end retainer 5 comprises a pressing surface 52 facing in the pressing direction D2 . In this example, the cutting surface 51 transitions smoothly and / or tangentially into the pressing surface 52 . In this way, the trailing end TE that is formed can be contacted by said pressing surface 52 without any abrupt changes in direction which could leave imprints in the tire component 91 . Alternatively, the end retainer 5 may change direction more abruptly or include a step at the transition from the cutting surface 51 to the pressing surface 52 .

[0053] In this example, the pressing surface 52 is curved or rounded . Hence, the pressing surface 52 defines several normal directions with at least a vector component in the pressing direction D2 .

[0054] As best seen in figure 8 , the end retainer 5 further comprises a blow-off section B . The blow-off section B is located in, at or near the pressing surface 52 . The blow-off section B is provided with one or more blow-off openings which are connectable to a source of compressed air . In particular, in this example, the blow-of f section B comprises a porous structure 53 . The one or more blow-of f openings are voids or pores 54 of the porous structure 53 . The pores 54 are large enough to be accessible or permeable to gases , in particular to compressed air, while being small enough to prevent collection of dust and / or other contaminants , such as rubber particles . In this example , the pores 54 are evenly or uniformly distributed over the blow-of f section B . Preferably, the pores 54 define a relative large void fraction inside the boundaries of the blow-off section B to allow for a relatively large flow rate of compressed air through the blow-of f section B .

[0055] In this example, the porous structure 54 is 3D printed or obtained through 3D printing . In particular, the porous structure 54 is formed integrally with the rest of the end retainer body 50 .

[0056] As shown in figure 6, the tire manufacturing station 1 further comprises a limiter or a stopper 8 for stopping the end retainer 5 after moving over a return distance Gl , G2 in the return direction Y . In this example , the stopper 8 is mounted to the frame or base 10 . The stopper 8 is movable relative to the extruder 2 or the base 10 for adj usting the return distance Gl , G2 . In particular, the stopper 8 has an extendable and retractable stopping surface 80 that can be retracted, as shown in figure 1 , to stop the end retainer 5 in the trailing end position Pl , and extended, as shown in figure 6 , to stop the end retainer 5 in a leading end position P2 , short of said trailing end position Pl . In this example, the stopper 8 is telescopically extendable and retractable . Alternatively, a dif ferent mechanism or linkage may be used to extend and retract the stopping surface 80 .

[0057] The tire manufacturing station 1 further comprises a control unit 12 that is functionally, electronically and / or operationally connected to one or more of the extruder 2 , the supply drive 6 , the end retainer drive 7 , the stopper 8 and / or the drum 11 for controlling the various operations of the tire manufacturing station 1 during the steps of the method detailed below .

[0058] The method for terminating the continuous strip 90 to form the tire component 91 with the use of the aforementioned tire manufacturing station 1 will be elucidated below with reference to figures 1-8 .

[0059] Figure 1 shows the situation in which the control unit 12 has controlled the end retainer drive 7 to return the end retainer 5 to the trailing end position Pl after a previous cycle of the method . The stopper 8 is retracted to allow the end retainer 5 to move into the trailing end position Pl . The end retainer 5 is retracted in the retraction direction R into a position above and / or clear of f the die 21 and the die opening 22 in said die 21 . In other words , the die opening 22 is unobstructed by the end retainer 5.

[0060] Figure 2 shows the situation in which the control unit 12 has controlled the extruder 2 to continuously extrude a length of the continuous strip 90 in the extrusion direction E at the extrusion speed VI . The continuous strip 90 is at least partially received onto the supply member 3 . The supply member 3 is rotated to supply the continuous strip 90 further in the supply direction S along the supply path P at the supply speed V2 as the extruder 2 extrudes an additional length of the continuous strip 90 .

[0061] Figure 3 shows the situation in which the extruder

[0062] 2 has extruded the additional length of the continuous strip 90 . Part of said continuous strip 90 may already be applied and / or wound onto or around the drum 11 . When a sufficient length of the continuous strip 90 has been extruded, the control unit 12 controls the end retainer drive 7 to move the end retainer 5 in the shearing direction DI across the die 21 and / or the die opening 22 . When the end retainer 5 moves across the die 21 , the cutting surface 51 of said end retainer 5 cooperates with the die opening 22 of the die 21 to cutof f or terminate the continuous strip 90 in or between the die plane Z1 and the cutting plane Z2 . The cutting action can best be described a shear-cutting action or a guillotine cutting action . In particular, the cutting surface 51 cooperates with the edge 23 of the die opening 22 to shearcut the continuous strip 90 . The cutting action results in a clear or distinct cut, rather than a tear or break, between the continuous strip 90 and the tire component 91 that is formed by said cutting action .

[0063] Shortly prior to the cutting action, the extrusion speed VI is decreased, reduced to zero and preferably reversed to a negative value , as shown in figure 3 . In this example , the supply speed V2 is simultaneously increased . Hence , a speed dif ference is generated at which the supply speed V2 is greater than the extrusion speed VI , thereby slightly stretching the continuous strip 90 between the supply member

[0064] 3 and the extruder 2 . Consequently, the cross-sectional area of the continuous strip 90 can be reduced prior to the cutting action, in order to obtain a slightly tapered trailing end TE after the cutting action .

[0065] Note that in figure 3 , the cutting surface 51 still at least partially overlaps with the die opening 22 during the pressing of the trailing end TE onto the supply member 3 .

[0066] The termination of the continuous strip 90 forms a trailing end TE at the tire component 91 that is formed . As shown in figure 5 , a new length of the continuous strip 90 may be extruded, having a leading end LE .

[0067] As further shown in figure 3 , simultaneously with or shortly after terminating the continuous strip 90 , the end retainer 5 presses the trailing end TE in the pressing direction D2 onto the supply member 3 . In this example , the pressing direction D2 and the shearing direction DI are the same . Consequently, the end retainer 5 can be move linearly and / or in a single linear motion in the shearing direction DI to both cut-of f and press the trailing end TE onto the supply member 3 .

[0068] Figures 4 and 5 show the steps of moving the end retainer 5 together with the supply member 3 in the supply direction S while retaining the trailing end TE with the end retainer 5 on the supply member 3 along at least a part of the supply path P . In particular, in this example, the end retainer 5 is moved together with the supply member 3 along a retaining arc A about the roll axis X as the roller body 40 rotates about said roll axis X . In other words , the end retainer 5 follows the trailing end TE of the tire component 91 on the retaining surface 41 of the roller body 40 as it rotates . The end retainer 5 can closely follow the trailing TE as it is continuously pressed, with a constant pressing force, onto the retaining surface 41 by the shearing / pressing actuator 71 while simultaneously being moved in the supply direction S by the supply / return actuator 72 . During at least a part of the movement of the trailing end TE along the retaining arc A, the first chamber 42 of the supply member 3 may be connected to a source of partial vacuum to retain the trailing end TE to the retaining surface 41 with suction . Hence, the trailing end TE can be simultaneously pressed by the end retainer 5 and retained through suction by the supply member 3 .

[0069] Figure 5 further shows the situation in which the trailing end TE of the tire component 91 is separated from the end retainer 5 by retracting the end retainer 5 in a retraction direction R away from the supply member 3 . In this example , the retraction direction R is opposite to the pressing direction D2 . However, alternatively, the retraction direction R may be in line with the supply direction S to move the end retainer 5 out of reach of the supply member 3 in said supply direction S .

[0070] In this example , the separation is assisted by generating a flow, a j et or a puf f of compressed air J between the end retainer 5 and the trailing end TE as the end retainer 5 is retracted in the retraction direction R . In figures 5, 7 and 8 , several localized puffs of compressed air J are schematically shown . It will however be understood that , in case of the porous structure 53 , a far greater number of relatively small j ets of compressed air J will flow out of the porous structure 53 in a much more evenly or uni formly distributed .

[0071] Optionally, the second chamber 43 of the supply member 3 may be connected to a source of compressed air to further assist the separation of the trailing end TE from the supply member 3 at the transfer of the tire component 91 from the supply member 3 to the drum 11 .

[0072] Figure 6 shows the situation in which the control unit 12 has controlled the stopper 8 to extend its stopping surface 80 . The control unit 12 has further controlled the end retainer drive 7 to return the end retainer 5 in the return direction Y towards the extruder 2 . However, because of the extended stopper 8 , the return movement of the end retainer 5 is stopped in the leading end position P2 , short of the trailing end position Pl . In this position, the end retainer 5 can be moved in the pressing direction D2 towards the supply member 3 to press the leading end LE of the continuous strip 90 onto said supply member 3 , without terminating or shear-cutting the continuous strip 90 at the die 21 . In particular, the end retainer 5 , when moving in the pressing direction D2 in said leading end position P2 remains well clear of and / or spaced apart from the die 21 in the extrusion direction E . Hence, the continuous strip 90 is only deflected towards the supply member 3 by the end retainer, rather than cut-of f .

[0073] From the situation as shown in figure 6, the end retainer 5 may be controlled to move in a similar following motion to the motion as shown in figures 4 and 5, while retaining the leading end LE to the supply member 3 . After said following motion, the end retainer 5 may be separated from the leading end LE in a similar manner to figure 5 , and returned towards the extruder 2 in a similar manner to figure 6. In such a scenario, the stopper 8 may be retracted again to allow the end retainer 5 to return to the trailing end position Pl , after which the previously described method may be repeated for another cycle .

[0074] It is to be understood that the above description is included to illustrate the operation of the preferred embodiments and is not meant to limit the scope of the invention . From the above discussion, many variations will be apparent to one skilled in the art that would yet be encompassed by the scope of the present invention .

[0075] LIST OF REFERENCE NUMERALS

[0076] 1 tire manufacturing station

[0077] 10 base

[0078] 11 drum

[0079] 12 control unit

[0080] 2 extruder

[0081] 20 extruder head

[0082] 21 extruder die

[0083] 22 extruder opening

[0084] 23 edge

[0085] 3 supply member

[0086] 4 applicator roll

[0087] 40 roller body

[0088] 41 retaining surface 42 vacuum chamber 43 compressed-air chamber 5 end retainer

[0089] 50 retainer body 51 cutting surface 52 pressing surface 53 porous structure 54 pores 6 supply member drive 7 end retainer drive

[0090] 71 shearing / pressing actuator 72 supply / return actuator 8 stopper

[0091] 90 continuous strip 91 tire component A retaining arc B blow-of f section C circumferential direction DI shearing direction D2 pressing direction E extrusion direction G1 first return distance G2 second return distance J puff of compressed air LE leading end P supply path Pl trailing end position P2 leading end position R retraction direction S supply direction TE trailing end VI extrusion speed V2 supply speed X roll axis Y return direction

[0092] Z1 die plane Z2 cutting plane

Claims

22C L A I M S1 . Method for terminating a continuous strip to form a tire component, wherein the method comprises the steps of : a) continuously extruding the continuous strip with an extruder, wherein the extruder comprises a die with a die opening for shaping the continuous strip ; b) receiving the continuous strip from the extruder onto a supply member, wherein the supply member is configured for supplying the continuous strip further in a supply direction along a supply path; c) moving an end retainer in a shearing direction across said die, wherein the end retainer comprises a cutting surface that cooperates with the die opening to shear cut the continuous strip at the die, thereby forming a trailing end of the tire component ; d) pressing the trailing end with the end retainer in a pressing direction onto the supply member ; and e ) moving the end retainer together with the supply member in the supply direction while retaining the trailing end with the end retainer on the supply member along at least a part of the supply path .2 . Method according to claim 1 , wherein the shearing direction is perpendicular to the supply direction .3 . Method according to claim 1 or 2 , wherein the pressing direction is the shearing direction .4 . Method according to any one of the preceding claims , wherein the end retainer continues to move linearly in the shearing direction after the shear cutting in step c ) until the end retainer presses the trailing end onto the supply member in step d) .

5. Method according to any one of the preceding claims , wherein the extruder continuously extrudes the continuous strip in step a) in an extrusion direction, wherein the die opening extends in a die plane perpendicular to theextrusion direction, wherein the cutting surface, in step c) , is positioned to extend in a cutting plane parallel or substantially parallel to the die plane .

6. Method according to claim 5 , wherein the cutting surface still at least partially overlaps with the die opening during the pressing in step d) and prior to step e ) .7 . Method according to claim 5 or 6, wherein the cutting plane , in step c) , extends at a die clearance from the die plane of less than three millimeters , preferably less than two millimeters and most preferably less than one millimeter .8 . Method according to any one of the preceding claims , wherein the supply member is an applicator roll with a roller body that is rotatable about a roll axis and that defines a retaining surface extending in a circumferential direction about the roll axis , wherein the end retainer is moved together with the supply member in step e ) along a retaining arc about the roll axis as the roller body rotates about said roll axis .

9. Method according to claim 8 , wherein the retaining arc is at least ten degrees , preferably at least twenty degrees , and most preferably at least thirty degrees .10 . Method according to any one of the preceding claims , wherein the method further comprises the step of : f ) separating the trailing end of the tire component from the end retainer after step e ) by retracting the end retainer in a retraction direction away from the supply member .11 . Method according to claim 10 , wherein the separation in step f ) is assisted by providing compressed air between the end retainer and the trailing end as the end retainer is retracted in the retraction direction .12 . Method according to any one of the preceding claims , wherein the method further comprises the step of : g) returning the end retainer over a return distance in a return direction towards the extruder .13 . Method according to claim 12 , wherein the method further comprises the step of : h) adj usting the return distance prior to or during step g) by moving a stopper relative to the extruder, wherein the end retainer is moved in the return direction until the end retainer contacts the stopper in said return direction .14 . Method according to any one of the preceding claims , wherein the extruder is configured for extruding the continuous strip at an extrusion speed and wherein the supply member is configured for supplying the continuous strip in the supply direction at a supply speed, wherein the method, between steps b) and c) , comprises the step of generating a speed difference between the extrusion speed and the supply speed at which the supply speed is greater than the extrusion speed .15 . Method according to claim 14 , wherein the extrusion speed is decreased, reduced to zero or reversed to a negative value, and / or wherein the supply speed is increased .16 . Tire manufacturing station for terminating a continuous strip to form a tire component , wherein the tire manufacturing station comprises an extruder for continuously extruding the continuous strip, wherein the extruder comprises a die with a die opening for shaping the continuous strip, wherein the tire manufacturing station further comprises a supply member for receiving the continuous strip from the extruder and for supplying the continuous strip further in a supply direction along a supply path, wherein the tire manufacturing station further comprises an end retainer that is movable relative to the extruder in a shearing direction across the die, an end retainer drive for moving the end retainer and a control unit that is operationally connected to the end retainer drive for controlling movement of the end retainer, wherein the control unit is configured for : moving the end retainer in the shearing25 direction across the die, wherein the end retainer comprises a cutting surface that cooperates with the die opening to shear cut the continuous strip at the die , thereby forming a trailing end of the tire component ; moving the end retainer in a pressing direction towards the supply member to press the trailing end onto said supply member; and moving the end retainer together with the supply member in the supply direction while retaining the trailing end with the end retainer on the supply member along at least a part of the supply path .17 . Tire manufacturing station according to claim16 , wherein the extruder is configured for continuously extruding the continuous strip in an extrusion direction, wherein the die opening extends in a die plane perpendicular to the extrusion direction, wherein the cutting surface, during the shear cutting of the continuous strip, extends in a cutting plane parallel or substantially parallel to the die plane .18 . Tire manufacturing station according to claim17 , wherein the cutting plane, during the shear cutting of the continuous strip, extends at a die clearance from the die plane of less than three millimeters , preferably less than two millimeters and most preferably less than one millimeter .19 . Tire manufacturing station according to any one of claims 16-18 , wherein the end retainer comprises a pressing surface facing in the pressing direction .20 . Tire manufacturing station according to claim 19 , wherein the pressing surface is rounded .21 . Tire manufacturing station according to claim 19 or 20 , wherein the end retainer comprises a blow-off section at the pressing surface, wherein the blow-of f section is provided with one or more blow-off openings which are connectable to a source of compressed air .22 . Tire manufacturing station according to claim 21 , wherein the blow-off section comprises a porous structure , wherein the one or more blow-of f openings are pores26 of the porous structure .23 . Tire manufacturing station according to claim 22 , wherein the porous structure is 3D printed or obtained through 3D printing .24 . Tire manufacturing station according to any one of claims 16-23 , wherein the control unit is further configured for returning the end retainer over a return distance in a return direction towards the extruder, wherein the tire manufacturing station comprises a stopper for stopping the end retainer after moving over the return distance in the return direction, wherein the stopper is movable relative to the extruder for adj usting the return distance .25 . Tire manufacturing station according to any one of claims 16-24 , wherein the supply member is an applicator roll with a roller body that is rotatable about a roll axis and that defines a retaining surface extending in a circumferential direction about the roll axis , wherein the control unit is configured for moving the end retainer together with the supply member along a retaining arc about the roll axis as the roller body rotates about said roll axis .— o— o— o— o— o— o— o— o—RM / HZ

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