Method for producing a pneumatic vehicle tyre, and pneumatic vehicle tyre

Abstract

A method for producing a pneumatic vehicle tyre (1) having a belt assembly (3), which has multiple reinforcing element plies (4, 5) and at least one electrically conductive ply (6), comprising at least the steps of: b) building up the belt assembly (3) on the carcass (2) provided, by at least the following two steps: b1) applying the reinforcing elements plies (4, 5) of the belt assembly, wherein the reinforcing element plies take up together, in their axial extent, an axial region (9) delimited by two axial bounds (8), b2) applying at least one electrically conductive filament (10, 10', 10'') at least to a radially outermost, already built-up component of the tyre to be created, for the purpose of building up the electrically conductive ply (6, 6'), wherein the radially outermost, already built-up component is the carcass (2) or one reinforcing element ply (4, 5) of the reinforcing element plies of the belt assembly (3) and wherein the at least one electrically conductive filament (10, 10', 10'') is arranged in such a way that, over the circumferential extent of the belt assembly (3), it crosses repeatedly in each case over at least one of the axial bounds (8). The invention also relates to a corresponding pneumatic vehicle tyre.

Description

[0001] Description

[0002] Method for producing a pneumatic vehicle tire and pneumatic vehicle tire

[0003] The invention relates to a method for producing a pneumatic vehicle tire comprising a carcass, in particular a radial carcass, and a belt assembly, wherein the belt assembly has a plurality of reinforcement layers and at least one electrically conductive layer. The invention also relates to a pneumatic vehicle tire comprising a carcass, a belt assembly resting radially on the outside of the carcass, and a tread, wherein the belt assembly has a plurality of reinforcement layers and at least one electrically conductive layer contacting the reinforcement layers, and wherein the reinforcement layers together occupy an axial region delimited by two axial boundaries in their axial extension.

[0004] It is known that it is advantageous to use tire components with rubber compounds with low hysteresis to reduce the rolling resistance of tires. Measures used in this regard include, in particular, the use of low-activity fillers, the use of a small amount of active filler, or the use of silicon dioxide (silica) instead of carbon black. Each of these measures results in an increase in the electrical resistance of the rubber compound or the component containing the compound. However, these tire components designed for low rolling resistance have such high electrical resistance that they are no longer sufficiently electrically conductive. Thus, the tire no longer has sufficient electrical conductivity, which is necessary for dissipating electrical charges resulting from the electrostatic charge of the vehicle.

[0005] To resolve the conflicting objectives between rolling resistance and electrical conductivity, various efforts are being made to ensure an electrically conductive path despite the increased use of rolling resistance-optimized rubber compounds. For example, DE10 2010 037 004 A1 discloses a pneumatic vehicle tire in which a component, which is a precursor, is spirally wrapped in an electrically conductive thread or is enclosed at the edges and then placed on the building drum. However, such an additional process step in the production of precursors is complex.

[0006] The development is moving towards optimising the rolling resistance of internal components of the pneumatic vehicle tyre, such as the reinforcement layers of the belt package, in particular the belt bandage.

[0007] A pneumatic vehicle tire, particularly of a radial design, generally comprises an air-impermeable inner layer, a particularly radial carcass containing reinforcements that extends from the crown region of the tire across the sidewalls to the bead area and is usually anchored there by wrapping tensile bead cores, a profiled tread located radially on the outside, and a belt assembly arranged radially between the tread and the carcass. The radial carcass comprises reinforcements that run largely radially in the bead area, particularly at an angle of 0° to 8°, preferably 0° to 5°, to the radial direction.

[0008] The belt package comprises a belt, which is covered radially on the outside with the belt bandage. The belt can comprise two or more reinforcement layers intersecting at an angle, which are pre-produced as a layer and applied to the tire to be formed.

[0009] The belt bandage can have one or more, preferably one, reinforcement layers, covers at least the belt edges and contains textile reinforcements running parallel and substantially in the circumferential direction, in particular at an angle of 0° to 8°, preferably of 0° to 5°, to the circumferential direction, which are embedded in a rubber mixture.

[0010] If a semi-finished product for the tire's reinforcement layers, in particular the band or strip, is provided with an electrically conductive thread on its surface during its production, it can happen during the cooling process as well as during the various winding or spooling processes that the electrically conductive thread is detached, damaged or severed, whereby the electrical conductivity of the tire cannot be reliably guaranteed.

[0011] A tire can be considered sufficiently electrically conductive if its leakage resistance is at most 1 x 10 A 8 ohms. The electrical leakage resistance of a pneumatic vehicle tire can be measured according to ISO 16392:2017.

[0012] The objective is to develop a method for producing a pneumatic vehicle tire that, while improving processability, enables sufficient electrical conductivity of the tire, particularly in the belt assembly area. At the same time, the belt assembly should be designed with low rolling resistance.

[0013] The task also includes a pneumatic vehicle tire that has sufficient electrical conductivity in the area of ​​the belt package and whose belt package can be designed with low rolling resistance.

[0014] With regard to the method, the object is achieved in that the method comprises at least the following steps: a) providing the carcass on a building drum, b) building the belt package on the provided carcass by at least the following two steps: b1) applying the reinforcement layers of the belt package, wherein the reinforcement layers together occupy an axial area delimited by two axial boundaries in their axial extent, b2) applying at least one electrically conductive thread at least to a radially outermost already built-up component of the tire to be created for building the electrically conductive layer, wherein the radially outermost already built-up component is the carcass or a reinforcement layer of the reinforcement layers of the belt package and wherein the at least one electrically conductive thread is arranged in such a way,that it repeatedly crosses at least one of the axial boundaries over the circumference of the belt package, c) applying a tread radially outside the belt package, d) finishing the tire with further means.,

[0015] The process allows the individual reinforcement layers of the belt package to be prefabricated as semi-finished products without additional or modified process steps and then applied to the tire. Each reinforcement layer comprises reinforcements arranged largely parallel to one another, which are embedded in elastomeric material. The tire manufacturing process includes the additional step b2), in which the electrically conductive thread is applied to the radially outermost, already assembled component of the tire to be created.

[0016] Depending on whether the radially outermost already constructed component is the carcass or the radially outermost reinforcement layer of the belt package or a radially inner reinforcement layer of the belt package, step b2) takes place before step b1) or after step b1) or between the application of two reinforcement layers during step b1).

[0017] The electrically conductive thread is applied only at the building drum, so that the upstream processes, especially the production of semi-finished products, can remain unchanged. Damage to the electrically conductive thread before the tire is built is also avoided. The electrically conductive layer can be formed by at least one electrically conductive thread.

[0018] According to the invention, the electrically conductive thread is applied in such a way that it comes into contact with the radially outermost already assembled component on a radially outer surface. Furthermore, the electrically conductive thread is arranged in such a way that it repeatedly crosses at least one of the axial boundaries over the circumference of the belt package. The electrically conductive thread thus projects beyond the axial region and thus beyond the axial extent of the reinforcement layers of the belt package and there contacts, i.e. axially outside the axial region, at least one further component of the tire, preferably the carcass and / or a sidewall of the tire. By simply adjusting the axial extent of the thread, the overlap with the at least one further component can be adjusted and thus the electrically conductive contact can be controlled.

[0019] The electrically conductive thread forms an electrically conductive connection from the axial region of the belt package to the axial region outside this region. The electrical conductivity of the tire in the region of the belt package can be ensured, while the reinforcement layers of the belt package, in particular the rubber compound of reinforcement layers of the belt package arranged radially within the electrically conductive layer, can be improved with regard to other properties. In particular, the rubber compound of one or more reinforcement layers of the belt package can be designed to have low rolling resistance, in particular to be insufficiently electrically conductive.

[0020] The repeated crossing of the electrically conductive thread over the circumference enables the electrical conductivity of the tire to be more independent of the position of the tire and of interruptions in the electrically conductive thread.

[0021] The electrically conductive layer can be formed by the at least one electrically conductive thread applied in step b2). Thus, an electrically conductive layer is provided that enables sufficient electrical conductivity of the tire without additionally increasing the tire's radial expansion.

[0022] A method for producing a vehicle tire is provided which, with improved processability, enables sufficient electrical conductivity of the tire, particularly in the area of ​​the belt assembly. At the same time, the belt assembly can be designed with low rolling resistance. The method according to the invention is explained in more detail below using advantageous embodiments of the invention, but is not limited to these.

[0023] An advantageous embodiment is provided in step b2) by arranging the electrically conductive thread such that it repeatedly crosses both axial boundaries of the axial region over the circumference of the belt package. This enables the dissipation of electrical charges on both axial sides of the axial region. This improves the dissipation of electrical charges and improves the reliability of the electrically conductive path.

[0024] A further advantageous embodiment is provided in that, in step b2), the electrically conductive thread is arranged on both sides of the axial boundary, axially spaced from the respective axial boundary, having turning regions. Preferably, the electrically conductive thread is arranged in an oscillating manner, particularly preferably in a wave-like, loop-like, or zigzag-like oscillating manner. This allows the electrically conductive thread to be applied particularly easily such that it crosses at least one of the axial boundaries multiple times over the circumference of the belt package.

[0025] The turning areas can have a bend or a kink. They can be arranged in an oscillating manner, preferably in a wave-like, loop-like, or zigzag-like oscillating pattern. Applying the thread is particularly easy if the thread is arranged in a wave-like oscillating pattern.

[0026] A further advantageous embodiment is provided in that in step b2) two or more electrically conductive threads are applied at least to the same radially outermost, already constructed component of the tire to be created to construct the electrically conductive layer, wherein a first thread of the electrically conductive threads is arranged such that it repeatedly crosses at least one of the axial boundaries over the circumference of the belt package and a second thread of the electrically conductive threads is arranged such that it repeatedly crosses at least the other axial boundary over the circumference of the belt package, preferably that at least two of the electrically conductive threads are arranged repeatedly crossing one another over the circumference of the tire.

[0027] By placing two or more electrically conductive threads in the same electrically conductive layer, the electrically conductive contact area and thus the conductivity are improved. The electrically conductive threads can also be arranged so that they repeatedly cross both axial boundaries.

[0028] Preferably, the threads are arranged so that they repeatedly cross each other around the circumference of the tire. At the intersections, the threads make electrically conductive contact. This makes the electrically conductive path even more robust against local interruptions. The intersections can be arranged inside or outside the axial region.

[0029] In an oscillating arrangement with turning points on both sides of the respective axial boundary, the threads can be arranged out of phase with each other and cross each other repeatedly.

[0030] The two or more electrically conductive threads of the same electrically conductive layer may be a single continuous thread arranged over more than one revolution of the tire. However, they may also be two or more separate threads.

[0031] A further advantageous embodiment is provided in that the electrically conductive thread is wound or spooled in step b2). This enables a particularly simple and reliable manufacturing process on a construction drum.

[0032] A further advantageous embodiment is provided in that in step b2) the radially outermost already constructed component of the tire to be created is a radially outermost reinforcement layer of the belt package or a radially inner reinforcement layer of the belt package or the carcass, preferably the radially outermost reinforcement layer of the belt package, of the tire to be created.

[0033] An advantageous embodiment is provided in that, in step b2), the radially outermost, already assembled component of the tire to be created is a radially outermost reinforcement layer of the belt package. This is generally a belt bandage layer whose preferably textile reinforcements are arranged at an angle of 0° to 5° to the circumferential direction.

[0034] The electrically conductive layer is thus the radially outermost layer of the belt package. This allows the rubber compound of at least the radially outermost reinforcement layer, in particular the belt bandage, to be designed to have particularly low rolling resistance while simultaneously ensuring sufficient electrical conductivity from the radially inner side of the tread to other components located axially outside the axial region, such as the sidewall and / or carcass.

[0035] An advantageous embodiment is provided in that, in step b2), the radially outermost, already constructed component of the tire to be created is a radially inner reinforcement layer of the belt package. This can be a reinforcement layer of the belt. The electrically conductive layer is arranged at least partially radially between two radially adjacent reinforcement layers of the belt package. An electrically conductive layer arranged in this way can also conduct electrical charge from within the belt package to axially outside the belt package and thus positively influence the electrical conductivity of the pneumatic vehicle tire.

[0036] An advantageous embodiment is provided in that, in step b2), the radially outermost, already constructed component of the tire to be created is the carcass. The electrically conductive layer is thus arranged at least partially radially between the reinforcement layers of the belt package and the carcass. Such an electrically conductive layer can also positively influence the electrical conductivity of the pneumatic vehicle tire.

[0037] A further advantageous embodiment is provided in that step b2) is carried out twice or at least three times, wherein the individual passes of step b2) differ from one another in the respective radially outermost already constructed component to which the electrically conductive thread is applied.

[0038] The belt assembly thus comprises two or at least three electrically conductive layers, each of which is at least partially separated from the other in the radial direction by at least one reinforcement layer. This further improves the conductivity of the belt assembly.

[0039] Preferably, the two or at least three electrically conductive layers overlap axially outside the axial region. Particularly preferably, the electrically conductive threads of the various electrically conductive layers cross axially outside the axial region and contact each other in an electrically conductive manner, thus further improving the reliability of the electrical conductivity.

[0040] It is preferred if step b2) is carried out once after the complete execution of step b1), whereby in this run the radially outermost already assembled component is the radially outermost strength member layer of the belt package.

[0041] The pneumatic vehicle tire produced by the method according to the invention can be for a passenger car, a van, a light truck, a two-wheeler, or a commercial vehicle. It is preferably a radial tire.

[0042] An advantageous embodiment is provided in that, in step b2), in addition to the at least one electrically conductive thread, an electrically conductive connecting thread is arranged such that it is largely oriented in the circumferential direction U and repeatedly crosses at least one of the electrically conductive threads over the circumference of the tire and is preferably arranged entirely axially between the two axial boundaries. The electrically conductive connecting thread can be designed like an electrically conductive thread in terms of its electrical conductivity, construction, fineness, and / or material composition. The electrically conductive threads and the connecting thread of a tire can be designed identically. However, they can also differ from one another.

[0043] At the intersections, the threads form electrically conductive contact. This makes the electrically conductive path even more robust against local interruptions. The largely circumferential orientation of the electrically conductive thread and the repeated intersections enable the most efficient distribution and dissipation of the tire's electrical charge, even if at least one electrically conductive thread is interrupted.

[0044] With regard to the pneumatic vehicle tire, the object is achieved in that the electrically conductive layer has at least one electrically conductive thread, wherein the at least one electrically conductive thread is arranged such that it repeatedly crosses at least one of the axial boundaries over the circumference of the belt package.

[0045] The electrically conductive thread is arranged such that it projects beyond the axial extent of the reinforcement layers of the belt package and contacts a component of the tire arranged axially outside the axial region, preferably the carcass. It thus forms an electrically conductive connection from the axial region of the belt package to axially outside this region. The electrical conductivity of the tire in the region of the belt package can be ensured, while the reinforcement layers of the belt package, in particular the rubber compound of reinforcement layers of the belt package arranged radially inside the electrically conductive layer, can be improved with regard to other properties. In particular, the rubber compound of one or more reinforcement layers of the belt package can be designed to have low rolling resistance, in particular to be insufficiently electrically conductive.

[0046] The repeated crossing of the electrically conductive thread over the circumference enables the electrical conductivity of the tire to be more independent of the position of the tire and of interruptions in the electrically conductive thread.

[0047] The electrically conductive layer can be formed by the at least one electrically conductive thread. This provides an electrically conductive layer that enables sufficient electrical conductivity of the tire without additionally increasing the tire's radial expansion.

[0048] A pneumatic vehicle tire is provided which has sufficient electrical conductivity in the area of ​​the belt package which can be designed with low rolling resistance.

[0049] If the electrically conductive thread rests on the tire bandage, it is arranged radially between the tire bandage and a tread. The electrically conductive path can be provided from an electrically conductive component of the tread, such as a carbon center beam, via the electrically conductive thread to a component arranged axially outside the axial region, such as the sidewall or carcass.

[0050] In the following, the pneumatic vehicle tire according to the invention is explained in more detail using advantageous embodiments according to the invention, without, however, being limited to these.

[0051] An advantageous embodiment is provided by arranging the electrically conductive thread such that it repeatedly crosses both axial boundaries around the circumference of the belt package. This enables the dissipation of electrical charges on both axial sides of the axial region. This improves the dissipation of electrical charges and improves the reliability of the electrically conductive path.

[0052] A further advantageous embodiment is provided in that the electrically conductive thread is arranged on both sides of the axial boundary at an axial distance from the respective axial boundary, having turning regions, preferably that the electrically conductive thread is arranged in an oscillating manner, particularly preferably that the thread is arranged in a wave-like, loop-like or zigzag-like oscillating manner.

[0053] This creates a particularly simple arrangement in which the electrically conductive thread crosses at least one of the axial boundaries multiple times over the circumference of the belt package. The turning areas can have a bend or a kink. They can be arranged in an oscillating manner, preferably in a wave-like, loop-like, or zigzag-like oscillating manner.

[0054] Particularly preferably, the thread is arranged in a wave-like, oscillating manner.

[0055] A further advantageous embodiment is provided in that the electrically conductive layer has two or more electrically conductive threads, wherein a first thread of the electrically conductive threads is arranged such that it repeatedly crosses at least one of the axial boundaries over the circumference of the belt package and a second thread of the electrically conductive threads is arranged such that it repeatedly crosses at least the other axial boundary over the circumference of the belt package, preferably that at least two of the electrically conductive threads are arranged repeatedly crossing one another over the circumference of the tire.

[0056] Two or more threads improve the electrically conductive contact area and thus the conductivity. The electrically conductive threads can also be arranged so that they repeatedly cross both axial boundaries. Preferably, the threads are arranged so that they repeatedly cross each other. At the intersections, the threads make electrically conductive contact. This makes the electrically conductive path even more robust against local interruptions. The intersections can be arranged inside or outside the axial region.

[0057] In an oscillating arrangement with turning points on both sides of the respective axial boundary, the threads can be arranged out of phase with each other and cross each other repeatedly.

[0058] The two or more electrically conductive threads of the same electrically conductive layer may be a single continuous thread arranged over more than one revolution of the tire. However, they may also be two or more separate threads.

[0059] A further advantageous embodiment is provided in that an electrically conductive layer of the at least one electrically conductive layer is arranged from the radial outside on the radially outermost reinforcement layer of the belt package and / or in that an electrically conductive layer of the at least one electrically conductive layer is arranged between two reinforcement layers of the belt package and / or in that an electrically conductive layer of the at least one electrically conductive layer is arranged between the radially innermost reinforcement layer of the belt package and the carcass.

[0060] The belt package can thus have exactly one electrically conductive layer, which is arranged from the radial outside on the radially outermost reinforcement layer of the belt package or layer between two reinforcement layers of the belt package or between the radially innermost reinforcement layer of the belt package and the carcass. The electrically conductive layer is preferably arranged from the radial outside on the radially outermost reinforcement layer, which is generally a belt bandage layer. However, the belt package can also have two or at least three electrically conductive layers. Preferably, at least one of the electrically conductive layers is arranged from the radial outside on the radially outermost reinforcement layer, which is generally a belt bandage layer.

[0061] The belt assembly thus comprises two or at least three electrically conductive layers, each of which is radially separated by at least one reinforcement layer. This further improves the conductivity of the belt assembly.

[0062] Preferably, the two or at least three electrically conductive layers overlap axially outside the axial region in the radial direction. Particularly preferably, the electrically conductive threads of the various electrically conductive layers cross axially outside the axial region and contact each other in an electrically conductive manner, thus further improving the reliability of the electrical conductivity.

[0063] An advantageous embodiment is provided in that the electrically conductive layer comprises an electrically conductive connecting thread, which is arranged such that it is largely aligned in the circumferential direction U and repeatedly crosses at least one of the electrically conductive threads over the circumference of the tire and is preferably arranged entirely axially between the two axial boundaries. The electrically conductive connecting thread can be varied in its electrical conductivity, construction, fineness and / or

[0064] The material composition can be designed like an electrically conductive thread. The electrically conductive threads and the connecting thread of a tire can be identical. But they can also be different.

[0065] At the intersections, the threads form electrically conductive contact. This makes the electrically conductive path even more robust against local interruptions. The largely circumferential orientation of the electrically conductive thread and the repeated intersections enable the most efficient distribution and dissipation of the tire's electrical charge, even if at least one electrically conductive thread is interrupted.

[0066] The pneumatic vehicle tire according to the invention can be produced by the method according to the invention.

[0067] The pneumatic vehicle tire can be for a passenger car, a van, a light truck, a two-wheeler, a commercial vehicle, an industrial tire, or an agricultural tire. It is preferably a radial tire.

[0068] In the following, advantageous embodiments of the method according to the invention and of the pneumatic vehicle tire according to the invention are explained in more detail, without, however, being limited to these.

[0069] An advantageous embodiment is provided in that the electrically conductive thread has an electrical resistance of maximum 6.5 x 10 A 6 ohms per 30 cm. The electrical resistance of the electrically conductive thread can be measured at a temperature of 22°C + / - 1°C and a humidity of 55% + / - 5%. With such an electrically conductive thread, sufficient conductivity of the belt package can be achieved.

[0070] A further advantageous embodiment is provided in that the electrically conductive thread is a textile thread, preferably comprising filaments made of PES or PA, particularly preferably comprising filaments made of PET or PA 6.6, and in that the textile thread is formed with an electrically conductive adhesive impregnation.

[0071] Such a textile reinforcement with an electrically conductive adhesive impregnation is ideally suited as an electrically conductive thread. The adhesive impregnation ensures a simple and permanent bond between the thread and the surrounding rubber compound. The electrically conductive adhesive impregnation enables the cost- and process-efficient use of a textile thread that can itself exhibit comparatively low electrical conductivity.

[0072] To ensure sufficient electrical conductivity of the electrically conductive adhesive impregnation of the textile thread, it may contain a sufficient amount of carbon black. The electrically conductive adhesive impregnation may, for example, contain at least 20%, preferably at least 25%, and particularly preferably at least 30% carbon black as a solution fraction.

[0073] The properties of the textile thread can be optimized by the choice of the textile material and the construction.

[0074] The textile thread comprises or is formed from a polymer. The textile thread can comprise or be formed from polyamide (PA), preferably PA 6.6 or PA 6 or PA 4.6. The textile thread can comprise or be formed from polyester, preferably polyethylene terephthalate (PET).

[0075] The at least one polymer, preferably PA and / or PES, especially PA 6.6 and / or PA 4.6 and / or PET, of the textile thread can be wholly or partially a recycled polymer to improve sustainability. In the context of the present invention, the term "recycled polymer" refers to a polymer obtained by at least one recycling process. The recycling process can be any recycling process known to those skilled in the art, such as, in particular, chemical and / or mechanical recycling. However, the polymer of the textile thread can also be wholly or partially a non-recycled (original) polymer.

[0076] The at least one polymer, preferably PA and / or PES, in particular PA 6.6 and / or PA 4.6 and / or PET, of the textile thread can be wholly or partially a bio-based polymer to improve sustainability. The term “bio-based polymer” in the context of the present invention means a polymer which is composed entirely or at least partially of monomers obtained from biomass. As is known to those skilled in the art, the proportion of bio-based materials, i.e. the proportion of renewable raw materials in the polymer, can be determined according to ASTM D 6866 (C-14 method). However, the polymer can also be designed as a non-bio-based polymer, i.e., within the context of the invention, none of the starting monomers were obtained directly from biomass. It can be a conventional, in particular petroleum-based, polymer.

[0077] The textile thread can be made of exactly one textile material. However, the textile thread can also be a hybrid textile thread comprising different textile materials. The textile thread can be formed from a textile multifilament yarn. However, the textile reinforcement can also be formed from several textile multifilament yarns twisted together at the ends. The textile thread can also be formed from a monofilament or from at least two monofilaments twisted together.

[0078] A further advantageous embodiment is provided by the textile thread having a fineness of 50 dtex to 500 dtex, preferably 75 dtex to 450 dtex, particularly preferably 100 dtex to 400 dtex. Such a low fineness enables the electrically conductive thread to be sufficiently robust against damage. At the same time, the influence of the comparatively thin electrically conductive thread on the mechanical properties of the tire is minimal.

[0079] A further advantageous embodiment is provided in that the electrically conductive thread comprises one or more electrically conductive metallic filaments. The electrical conductivity of the electrically conductive thread comprising one or more electrically conductive metallic filaments can then be primarily determined by the electrically conductive metallic filaments. The electrically conductive thread comprising one or more electrically conductive metallic filaments can be formed from the one or more electrically conductive metallic filaments.

[0080] The electrically conductive thread comprising one or more electrically conductive metallic filaments can, however, also comprise at least one filament, in particular a multifilament yarn, made of a textile material, preferably of PES or PA, particularly preferably of PET, PA 6.6 or PA 4.6.

[0081] A further advantageous embodiment is provided by the electrically conductive thread comprising carbon fibers. Carbon fibers exhibit advantageously high electrical conductivity and advantageously high strength. The electrical conductivity of the electrically conductive thread can then be primarily determined by the electrically conductive carbon fibers. A complex additional electrically conductive adhesive impregnation of the electrically conductive thread to ensure sufficient electrical conductivity can be avoided. The electrically conductive thread can be designed without adhesive impregnation. At the same time, carbon fibers exhibit excellent strength properties, which prevents damage and possibly tearing of the electrically conductive thread during the winding process on the construction machine, and the associated interruption of the electrically conductive path. Compared to textile materials such as PET or PA 6, this is advantageous.6 Carbon fibers also have the advantage of lower moisture absorption, which reduces air pockets caused by the evaporation of moisture.

[0082] Preferably, the electrically conductive thread comprising carbon fibers is formed entirely from carbon fibers. The electrically conductive thread exhibits the advantageous electrical conductivity and strength provided by the carbon fibers to a particularly high degree. However, the electrically conductive thread comprising carbon fibers can also comprise at least one filament, in particular a multifilament yarn, made of a textile material, preferably PES or PA, particularly preferably PET, PA 6.6, or PA 4.6. In such a hybrid thread, advantageous properties of the different materials and / or the thread construction are combined.

[0083] An advantageous embodiment of the electrically conductive thread comprising carbon fibers is provided by the electrically conductive thread having a fineness of 100 dtex to 800 dtex, preferably 200 dtex to 700 dtex, particularly preferably 300 dtex to 700 dtex. Such a low fineness enables the electrically conductive thread to be sufficiently robust and resistant to damage. At the same time, the influence of the comparatively thin electrically conductive thread on the mechanical properties of the tire is minimal.

[0084] The invention encompasses all advantageous embodiments, which are reflected, among other things, in the patent claims. In particular, the invention also encompasses embodiments resulting from the combination of different features with varying degrees of preference, so that a combination of a first feature designated as "preferred" with another feature designated, for example, as "particularly preferred" is also encompassed by the invention.

[0085] Further features, advantages and details of the invention will now be explained in more detail with reference to the schematic drawings which illustrate exemplary embodiments.

[0086] Fig. 1 to 3 cross-sections of the tire to be built at different stages of the process;

[0087] Figs. 4 to 6 each show a plan view of the tire to be built after step b2); Fig. 7 shows a pneumatic vehicle tire according to the invention. Figures 1 to 3 show cross sections of the tire to be built at various stages of the method for producing a pneumatic vehicle tire 1 comprising a carcass 2 and a belt assembly 3, wherein the belt assembly 3 has a plurality of reinforcement layers 4, 5 and at least one electrically conductive layer 6.

[0088] In Figure 1, steps a) and b1) have already been carried out. According to step a), a carcass 2 was provided on a building drum 7. According to step b1), the reinforcement layers 4, 5 of the belt package 3 still to be completed were applied to the provided carcass 2. The reinforcement layers 4, 5 together occupy an axial region 9 delimited by two axial boundaries 8 in their axial extent. By way of example, the belt package 3 still to be completed with the electrically conductive layer (see Fig. 2) has two reinforcement layers 4 which cross at an angle and are covered by a radially outermost reinforcement layer 5, which here is a belt bandage layer covering at least the edges of the angular layers 4.

[0089] Figure 2 shows the assembly process after step b2), in which, to complete the belt assembly 3, an electrically conductive thread 10 has been applied to at least one radially outermost, already assembled component of the tire to be created, here the belt bandage layer 5, to construct the electrically conductive layer 6. The electrically conductive thread 10 was arranged such that it repeatedly crosses at least one of the axial boundaries 8, here, for example, both axial boundaries 8, over the circumference of the belt assembly. The electrically conductive thread 10 can have been wound or spooled in step b2).

[0090] In Figure 3, a tread 11 has already been applied radially outside the belt assembly 3 according to step c). The tread 11 has a carbon center beam 12, which represents an electrically conductive connection from a tread of the tire to the electrically conductive layer 6. Furthermore, sidewalls 13 have already been applied in Figure 3. Completion of the tire with further means includes, for example, the application of additional components such as the sidewall 13 (already completed in Figure 3) and the shaping vulcanization.

[0091] The electrically conductive layer 6 contacts other components axially outside the axial region 9, such as the carcass 2 and the sidewall 13. An electrically conductive connection from the electrically conductive layer 6 into a bead region can be established.

[0092] The components shown in Figures 1 to 7 can be designed as follows: The electrically conductive thread 10, 10', 10" and the electrically conductive connecting thread 101 each have an electrical resistance of maximum 6.5 x 10 A6 ohms / 30 cm. The electrical resistance can be measured at a temperature of 22°C + / - 1°C and an air humidity of 55% + / - 5%. The thread 10, 10', 10", 101 can each be a textile thread, preferably comprising filaments of PES or PA, particularly preferably comprising filaments of PET or PA 6.6, which is formed with an electrically conductive adhesive impregnation. The textile thread 10, 10', 10", 101 can have a fineness of 50 dtex to 500 dtex, preferably from 75 dtex to 450 dtex, particularly preferably from 100 dtex to 400 dtex. The thread 10, 10', 10", 101 may comprise or be formed from one or more electrically conductive metallic filaments. The electrically conductive thread 10, 10', 10" may comprise carbon fibers. The electrically conductive thread may be formed entirely or partially from carbon fibers.The electrically conductive thread comprising carbon fibers can have a fineness of 100 dtex to 800 dtex, preferably 200 dtex to 700 dtex, particularly preferably 300 dtex to 700 dtex. It can be formed without an adhesive impregnation.

[0093] All electrically conductive threads 10, 10', 10" as well as the electrically conductive connecting thread 101 of a tire can be of the same design.

[0094] The pneumatic vehicle tire 1 can be for a passenger car, a van, a light truck, a two-wheeler, a commercial vehicle, an industrial vehicle, or an agricultural vehicle. It is preferably a radial tire.

[0095] Figures 4, 5, and 6 each show different variants of the electrically conductive layer 6. In each case, a top view of the already assembled tire components after step b2) is shown. The electrically conductive thread 10, 10' was arranged in step b2) such that it has turning regions 14 on both sides of the respective axial boundary 8, axially spaced from the respective axial boundary 8. In Figures 4, 5, and 6, the thread 10, 10' is arranged in a wave-like oscillating manner. Alternatively, a loop-shaped or zigzag-shaped oscillating arrangement is also possible. At intersections 15 between electrically conductive threads 10, 10' and connecting threads 101, these make electrically conductive contact with one another.

[0096] Figure 4 shows a plan view of the already assembled tire components after step b2), wherein, by way of example, the radially outermost already assembled component of the tire to be created is the radially outermost reinforcement layer 5 of the tire (shown hatched), in particular a belt bandage layer. This can be the structure shown in Figure 2. The electrically conductive thread 10 was arranged such that it repeatedly crosses both axial boundaries 8 of the axial region 9 over the circumference of the belt package.In step b2), an electrically conductive connecting thread 101 was additionally arranged such that it is largely aligned in the circumferential direction U, in particular at an angle of 0° to 8°, preferably from 0° to a maximum of 5° to the circumferential direction U, and repeatedly crosses the electrically conductive thread 10 over the circumference of the tire at intersections 15 in an electrically conductive manner and is arranged entirely axially between the two axial boundaries 8.

[0097] Figure 5 shows a plan view of the already constructed tire components according to an alternative embodiment of step b2). In step b2), two or more electrically conductive threads 10, 10' were applied at least to the radially outermost already constructed component of the tire to be created, here, for example, a radially inner reinforcement layer 4 (shown hatched) of the belt assembly 3 to be created, to construct the one electrically conductive layer 6. A first thread 10 of the electrically conductive threads was arranged such that it repeatedly crosses at least one of the axial boundaries 8 over the circumference of the belt assembly 3, and a second thread 10' of the electrically conductive threads was arranged such that it repeatedly crosses at least the other axial boundary 8 over the circumference of the belt assembly. The electrically conductive layer 6 constructed in this way is thus formed from the two electrically conductive threads 10, 10'.The two electrically conductive threads 10, 10' are arranged to repeatedly cross each other and make electrically conductive contact at the intersections 15. In the illustrated embodiment, the threads 10, 10' each cross exactly one of the axial boundaries 8. In the illustrated case, step b2) is performed between the application of two reinforcement layers of the belt package during step b1).

[0098] Figure 6 shows a further embodiment of the method. It shows a plan view of the already assembled tire components when step b2) has been carried out twice, wherein the individual runs of step b2) differ from one another in the respective radially outermost already assembled component to which the electrically conductive thread 10, 10" is applied. In the first run of step b2), a radially inner reinforcement layer 4 (shown with broken hatching) of the belt package 3 was the radially outermost already assembled component to which the electrically conductive thread 10 was applied. Thereafter, according to step b1), at least one remaining reinforcement layer 5 (shown with hatching) of the belt package was applied.Subsequently, in the second pass of step b2), another electrically conductive thread 10" of the electrically conductive threads was applied, wherein the radially outermost already constructed component was the radially outermost reinforcement layer 5 of the belt package to be created. The electrically conductive threads 10, 10" were arranged such that they repeatedly cross both axial boundaries 8 of the axial region 9 over the circumference of the belt package. The belt package thus has two electrically conductive layers 6, 6' which overlap axially outside the axial region 9. The electrically conductive thread 10 of the electrically conductive layer 6 and the electrically conductive thread 10" of the electrically conductive layer 6' are in electrically conductive contact axially outside the axial region 9. The electrically conductive thread 10 of the electrically conductive layer 6 is arranged radially between the reinforcement layers 4 and 5, at least in sections.

[0099] Figure 7 shows a schematic cross-section of a pneumatic vehicle tire 1 according to the invention. The pneumatic vehicle tire 1 has an air-impermeable inner layer (not shown), a carcass 2 containing, in particular, radial reinforcements, which extends from the crown region of the tire over the sidewalls into the bead regions and is anchored there mostly by wrapping tensile bead cores, a profiled tread 11 located radially outwardly and a belt package 3 arranged radially between the tread 11 and the carcass 2 and resting on the carcass. The radial carcass has reinforcements which, in the bead region, run largely in the radial direction, in particular at an angle of 0° to 8°, preferably of 0° to 5°, to the radial direction.

[0100] The belt package 3 comprises a belt with a plurality of reinforcement layers 4, arranged in particular at an angle of at least 15° to the circumferential direction, a radially outermost reinforcement layer 5, designed in particular as a belt bandage layer, and, in the illustrated embodiment, at least one electrically conductive layer 6 contacting the radially outermost reinforcement layer 5 from the radial outside. The reinforcement layers 4, 5 together occupy, in their axial extent, an axial region 9 delimited by two axial boundaries 8. The electrically conductive layer 6 is formed from at least one electrically conductive thread 10. This is arranged such that it repeatedly crosses at least one of the axial boundaries 8 over the circumference of the belt package 3. The tread 11 has, by way of example, a carbon center beam 12, which represents an electrically conductive connection from a tread of the tire to the electrically conductive layer 6.The pneumatic vehicle tire 1 can have an electrically conductive layer 6 as illustrated in Figures 4 or 5. The pneumatic vehicle tire 1 can also have two electrically conductive layers 6, 6' (not shown), which are designed, for example, as shown in Figure 6. The pneumatic vehicle tire 1 can be manufactured by the method according to the invention illustrated in Figures 1 to 3 and 4, 5 and / or 6.

[0101] List of reference symbols

[0102] (part of the description)

[0103] 1 pneumatic vehicle tire

[0104] 2 carcass

[0105] 3 belt pack

[0106] 4 radial inner strength member layer of the belt package

[0107] 5 radially outermost reinforcement layer of the belt package

[0108] 6.6' electrically conductive layer

[0109] 7 construction drum

[0110] 8 axial limit

[0111] 9 axial area

[0112] 10, 10', 10" electrically conductive thread

[0113] 11 treads

[0114] 12 Carbon Center Beam

[0115] 13 Side wall

[0116] 14 Turning area

[0117] 15 Intersection

[0118] 101 Connecting thread aR axial direction rR radial direction

Claims

Patent claims 1. A method for producing a pneumatic vehicle tire (1) comprising a carcass (2) and a belt assembly (3), wherein the belt assembly (3) has a plurality of reinforcement layers (4, 5) and at least one electrically conductive layer (6), the method comprising at least the following steps: a) providing the carcass (2) on a building drum (7), b) building the belt assembly (3) on the provided carcass (2) by at least the following two steps: b1) applying the reinforcement layers (4, 5) of the belt assembly, wherein the reinforcement layers together occupy an axial region (9) delimited by two axial boundaries (8) in their axial extent, b2) applying at least one electrically conductive thread (10, 10', 10") at least to a radially outermost, already constructed component of the tire to be created for building the electrically conductive layer (6, 6'),wherein the radially outermost already constructed component is the carcass (2) or a reinforcement layer (4, 5) of the reinforcement layers of the belt package (3), and wherein the at least one electrically conductive thread (10, 10', 10") is arranged such that it repeatedly crosses at least one of the axial boundaries (8) over the circumference of the belt package (3), c) applying a tread (11) radially outside the belt package (3), d) finishing the tire (1) with further means.

2. Method according to claim 1, characterized in that in step b2) the electrically conductive thread (10, 10', 10") is arranged such that it repeatedly crosses both axial boundaries (8) of the axial region (9) over the circumference of the belt package (3).

3. Method according to at least one of the preceding claims, characterized in that in step b2) the electrically conductive thread (10, 10', 10") on both sides of the axial boundary (8) turning areas (14) is arranged, preferably that the electrically conductive thread is arranged in an oscillating manner, particularly preferably that the thread is arranged in a wave-like, loop-like or zigzag-like oscillating manner.

4. Method according to at least one of the preceding claims, characterized in that in step b2) two or more electrically conductive threads (10, 10') are applied at least to the radially outermost already constructed component of the tire to be created for constructing the electrically conductive layer (6), wherein a first thread (10) of the electrically conductive threads is arranged such that it repeatedly crosses at least one of the axial boundaries (8) over the circumference of the belt package (3) and a second thread (10') of the electrically conductive threads is arranged such that it repeatedly crosses at least the other axial boundary (8) over the circumference of the belt package, preferably that at least two of the electrically conductive threads are arranged repeatedly crossing one another over the circumference of the tire.

5. Method according to at least one of the preceding claims, characterized in that in step b2) the radially outermost already constructed component of the tire to be created is a radially outermost reinforcement layer (5) of the belt package (3) or a radially inner reinforcement layer (4) of the belt package (3) or the carcass (2), preferably the radially outermost reinforcement layer of the belt package, of the tire to be created.

6. Method according to at least one of the preceding claims, characterized in that step b2) is carried out twice or at least three times, wherein the individual passes of step b2) are in the respective radially outermost already constructed component to which the respective electrically conductive thread (10, 10”) is applied, differ from each other.

7. Method according to at least one of the preceding claims, characterized in that in step b2), in addition to the at least one electrically conductive thread (10, 10', 10"), an electrically conductive connecting thread (101) is arranged such that it is largely aligned in the circumferential direction U and repeatedly crosses at least one of the electrically conductive threads (10, 10', 10") over the circumference of the tire and is preferably arranged entirely axially between the two axial boundaries (8).

8. A pneumatic vehicle tire (1) comprising a carcass (2), a belt package (3) resting radially from the outside on the carcass, and a tread (11), wherein the belt package (3) has a plurality of reinforcement layers (4, 5) and at least one electrically conductive layer (6, 6') contacting at least one of the reinforcement layers (4, 5), and wherein the reinforcement layers (4, 5) together occupy, in their axial extent, an axial region (9) delimited by two axial boundaries (8), characterized in that the electrically conductive layer (6, 6') has at least one electrically conductive thread (10, 10', 10"), wherein the at least one electrically conductive thread (10, 10', 10") is arranged such that it repeatedly crosses at least one of the axial boundaries (8) over the circumference of the belt package (3).

9. Pneumatic vehicle tire (1) according to the preceding claim, characterized in that the electrically conductive thread (10, 10', 10") is arranged such that it repeatedly crosses both axial boundaries (8) over the circumference of the belt package (3).

10. Pneumatic vehicle tire (1) according to one of claims 8 to 9, characterized in that the electrically conductive thread (10, 10', 10") is arranged on both sides of the axial boundary (8) axially spaced from the respective axial boundary (8) having turning regions (14), preferably that the electrically conductive thread (10, 10', 10") is arranged in an oscillating manner, particularly preferably that the thread is arranged in a wave-like, loop-like or zigzag-like oscillating manner.

11. Pneumatic vehicle tire (1) according to one of claims 8 to 10, characterized in that the electrically conductive layer (6) has two or more electrically conductive threads (10, 10'), wherein a first thread (10) of the electrically conductive threads is arranged such that it repeatedly crosses at least one of the axial boundaries (8) over the circumference of the belt package and a second thread (10') of the electrically conductive threads is arranged such that it repeatedly crosses at least the other axial boundary (8) over the circumference of the belt package, preferably that at least two of the electrically conductive threads (10, 10') are arranged repeatedly crossing one another over the circumference of the tire.

12. Pneumatic vehicle tire (1) according to one of claims 8 to 11, characterized in that an electrically conductive layer (6, 6') of the at least one electrically conductive layer is arranged from the radial outside on the radially outermost reinforcement layer (5) of the belt package (3) and / or that an electrically conductive layer (6) of the at least one electrically conductive layer is arranged between two reinforcement layers (4, 5) of the belt package and / or that an electrically conductive layer of the at least one electrically conductive layer is arranged between the radially innermost reinforcement layer (4) of the belt package and the carcass (2).

13. Pneumatic vehicle tire according to at least one of claims 8 to 12, characterized in that the electrically conductive layer (6) has an electrically conductive connecting thread (101) which is arranged such that it is largely aligned in the circumferential direction U and repeatedly crosses at least one of the electrically conductive threads (10, 10', 10") over the circumference of the tire and is preferably arranged entirely axially between the two axial boundaries (8).

14. Method according to at least one of claims 1 to 7 and / or pneumatic vehicle tire according to at least one of claims 8 to 13, characterized in that the electrically conductive thread (10, 10', 10") has an electrical resistance of at most 6.5 x 10 A 6 Ohm / 30 cm.

15. Method according to at least one of claims 1 to 7 and 14 and / or pneumatic vehicle tire according to at least one of claims 8 to 14, characterized in that the electrically conductive thread (10, 10', 10") is a textile thread, preferably comprising filaments of a polyester (PES) or of a polyamide (PA), particularly preferably comprising filaments of polyethylene terephthalate (PET) or PA 6.6, and in that the textile thread is formed with an electrically conductive adhesive impregnation.

16. Method according to at least one of claims 1 to 7 and 14 and 15 and / or pneumatic vehicle tire according to at least one of claims 8 to 15, characterized in that the textile thread (10, 10', 10") has a fineness of 50 dtex to 500 dtex, preferably from 75 dtex to 450 dtex, particularly preferably from 100 dtex to 400 dtex.

17. Method according to at least one of claims 1 to 7 and 14 to 16 and / or pneumatic vehicle tire according to at least one of claims 8 to 16, characterized in that the electrically conductive thread (10, 10', 10") has one or more electrically conductive metallic filaments.

18. Method according to at least one of claims 1 to 7 and 14 and / or pneumatic vehicle tire according to at least one of claims 8 to 14, characterized in that the electrically conductive thread (10, 10', 10") comprises carbon fibers or is formed therefrom and in particular has a Fineness of 100 dtex to 800 dtex, preferably from 200 dtex to 700 dtex, particularly preferably from 300 dtex to 700 dtex.

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