VEHICLE TIRES AND METHOD FOR MANUFACTURING A BELT BANDAGE

Description

[0001] The invention relates to a vehicle tire with a coil bandage, wherein the coil bandage comprises reinforcing elements embedded in a rubber compound, wherein the rubber compound in a first section of the coil bandage is electrically non-conductive.

[0002] It is increasingly common to use low rolling resistance rubber compounds to reduce the rolling resistance of vehicle tires, although these low rolling resistance compounds often have a higher specific electrical resistance than conventional rubber compounds. For example, it is common to use silica instead of carbon black as a filler in a rubber compound, which can achieve a beneficially low rolling resistance, but can result in high electrical resistance between the road surface and the rim.

[0003] The challenge is therefore to create electrical bridges within the vehicle tire that must also overcome, for example, a coiled bandage positioned between the road surface and the rim if the coiled bandage exhibits excessive electrical resistance. EP 3 325 286 B1 provides for this purpose a vehicle tire with a tread, wherein the tread comprises a tread cap with a running surface, a tread base, and at least one electrically conductive conductive strip, the conductive strip extending radially from the tread base to the running surface. The vehicle tire according to EP 3 325 286 B1 further comprises an electrically non-conductive belt bandage with a plurality of gaps arranged beneath the tread base. The tread base consists of an electrically conductive material, and the gaps in the belt bandage are filled with the same electrically conductive material as the tread base.One disadvantage of the described state of the art is that the strength is reduced by the gaps in the belt bandage, which can have a negative impact on the integrity and performance of a vehicle tire, especially at high rolling speeds.

[0004] DE 10 2007 004327 A1 describes a tire with an electrically conductive tread base and an electrically non-conductive tread cap, wherein the cap is produced by coiling a strip of material, wherein electrically conductive material is locally introduced into the tread, which establishes an electrically conductive connection between the outside of the cap and the base, and wherein the electrically conductive material is applied to at least one side of the cap strip during coiling, before the cap strip is applied. JP 2013 193580 A describes a tire with a passage area that penetrates a tread, wherein the passage area comprises a non-conductive cover rubber and conductive cords, one end of the cords being exposed on the tread surface and the other end being exposed on the inner surface of the tread.CN 1 646 334 A describes a tire with a belt reinforcement layer comprising reinforcing cord in the form of a polyethylene 2,6-naphthyl ester fiber line.

[0005] DE 11 2020 005755 T5 describes a tire with a belt cover layer that encloses organic fiber cord threads. JP 2005 041055 A describes a tire with a coiled rubber strip of low conductivity, wherein highly conductive material is discontinuously enclosed at several points so that it comes into contact with the road surface.

[0006] The invention is based on the objective of creating a vehicle tire with a belted casing that contributes to the lowest possible rolling resistance of the vehicle tire, while also maintaining a high level of electrical conductivity and strength. Furthermore, a method for manufacturing a belted casing in such a vehicle tire is to be provided.

[0007] The problem is solved according to the invention by making the rubber compound in a second section of the coil bandage electrically conductive.

[0008] The invention resolves the conflicting objectives of low rolling resistance, sufficient electrical conductivity, and high strength in a surprisingly simple manner. By designing the belt bandage as a coil bandage, sections with different properties, particularly regarding hysteresis and electrical conductivity, can be wound onto it. Because the entire belt bandage contains reinforcing elements and only one rubber compound is used to encase these elements in the different sections, the strength can be maintained at a high and uniform level across the entire circumference and transverse extent of the vehicle tire.

[0009] When the terms axial, radial, and circumferential are used, they refer to the vehicle tire as intended on a vehicle and its rolling motion. In this context, the radial direction refers to a direction perpendicular to and intersecting the vehicle tire's axis of rotation. Radially inward refers to the orientation facing radially toward the axis of rotation. Radially outward refers to the orientation facing radially away from the axis of rotation. The circumferential direction describes the direction of rolling motion around the axis of rotation. When the vehicle is moving forward, a tire positioned at the front circumferentially reaches a minimum distance to the road surface sooner during a 180° rotation than a tire positioned at the rear circumferentially.The axial direction refers to a direction parallel to the axis of rotation. Pointing axially inwards refers to an orientation that is axially aligned with a tire equator plane or tire equator line. The tire equator plane is a plane perpendicular to the vehicle tire's axis of rotation, passing through the center of the tire's axial width, with the tire equator line running within the tire equator plane and on the tire's surface. The transverse direction is defined as a direction consisting of components of the radial and / or axial directions.

[0010] The effects achieved with the features of the main claim are supported and further enhanced by preferred embodiments and configurations.

[0011] A coil bandage is a belt bandage wound from a length of material wound onto a belt. The coil bandage incorporates reinforcing elements, which preferably run along the length of the bandage as continuous cords along its length and can be made of materials such as aramid, nylon, PET, or mixtures of these materials.

[0012] A section of the coil bandage is preferably a continuous, uninterrupted section that preferably extends at least in an axial subsection over the entire circumference and overall over a portion of the axial width of the coil bandage. Alternatively, a section can, in principle, also have gaps and / or comprise several non-contiguous areas of the coil bandage. The invention also includes embodiments in which a section of the coil bandage is arranged in varying axial regions depending on its circumferential position. In the radial direction, the coil bandage can comprise a continuous section and / or two or more radially stacked sections, the radial structure of the coil bandage being able to vary depending on its circumferential position and / or its position in the axial direction.

[0013] A definition of an electrically conductive or non-electrically conductive rubber compound must first be formulated relatively, such that the specific resistance after vulcanization is lower in the electrically conductive rubber compound than in the electrically non-conductive rubber compound. A boundary between electrically conductive and non-conductive rubber compounds can be expressed in absolute terms such that an electrically conductive rubber compound preferably has a specific resistance of <1 × 10⁷ Ω cm to <1 × 10¹² Ω cm, and that an electrically non-conductive rubber compound preferably has a specific resistance of >1 × 10⁷ Ω cm to >1 × 10¹² Ω cm, where the specific resistance of the electrically conductive rubber compound is lower than that of the electrically non-conductive rubber compound.The wide range of specified limit values ​​results, among other things, from the possible variations in the geometries of assemblies that can be used in a vehicle tire: For example, the thicker the coil bandage in the second section, the lower the specific resistance of the conductive rubber compound must be in order not to exceed a given resistance for overcoming the coil bandage; for example, the larger the contact area between the second section of the coil bandage and a carbon center beam extending through the cap and base of a tread, the higher the specific resistance of the conductive rubber compound may be in order to remain below a given resistance on the path between the road surface and the rim. Alternatively or additionally, the specific application of the invention may influence meaningful limit values ​​for defining an electrically conductive or non-conductive rubber compound.For example, the discharge resistance of a tire classified as conductive according to WDK standard 110 / ISO 16392 must not exceed a value of 1 × 10⁶ < Ω; in this case, the electrically conductive rubber compound preferably has a specific resistance of < 1 × 10⁷ < Ω cm. For example, for original equipment on vehicles, such as those on the European market, a limit value for the resistance between the road surface and the rim of 1 × 10⁸ < Ω is common; in this case, the electrically conductive rubber compound preferably has a specific resistance of < 1 × 10¹⁰ < Ω cm. For example, the discharge resistance of a tire classified as "dissipative" according to WDK standard / ISO 16392 must not exceed a value of 1 × 10¹⁰ < Ω. In this case, the electrically conductive rubber compound preferably has a specific resistance of < 1 × 10 12 < Ω cm.

[0014] Preferably, the rubber compound in the first section is characterized by low hysteresis. Preferably, the rubber compound in the first section is better suited to minimizing the rolling resistance of the vehicle tire than the rubber compound in the second section. In this way, the first section can be optimized for good rolling resistance and the second section for electrical conductivity, with consistently high strength in both sections due to the reinforcing elements running through them. A suitable filler for the rubber compound in the first section is silica.

[0015] According to a preferred embodiment, the rubber compound is additionally electrically non-conductive in a third section, wherein the second section is bounded on one axial side by the first and third sections, respectively. The term "bounded on one axial side" in this context means that, at least in a partial region along the circumferential direction, there is a flush abutment and / or partial overlap between at least one winding of the first and third sections on one side and the second section on the other. In particular, the first and third sections can be located in the shoulder regions and the second section in the equatorial region of the vehicle tire, with the equatorial plane preferably intersecting the second section.This can be advantageous, among other reasons, because particularly in the shoulder regions, high speeds can lead to excessive heat generation due to hysteresis effects, which can be mitigated by using rubber compounds optimized for rolling resistance.

[0016] According to a further preferred embodiment, the rubber compound is additionally electrically non-conductive in a fourth section. The fourth section can be arranged at least partially radially below and / or above the second section. The fourth section can be arranged such that gaps remain in the axial and / or circumferential direction next to the portion of the fourth section arranged radially below and / or above the second section. In particular, the fourth section can be arranged such that gaps remain between the fourth section and the first section and / or between the fourth section and the third section and / or within the fourth section in the axial and / or circumferential direction. The gaps can be filled by the second section.In this case, the second section fills the gaps in the sense that the second section can be mechanically contacted radially above and / or radially below through the gaps, i.e., it is not obscured by the fourth section.

[0017] The fourth section can have a global axial width between 1% and 60% of the axial width of the vehicle tire, and preferably between 1% and 30% of the axial width of the vehicle tire. The global axial width of the fourth section can be measured between axial extreme positions, i.e., between two axially farthest possible positions of the fourth section, where the extreme positions may be located at different circumferential positions. The global axial width of the fourth section can be the same as the global axial width of the second section.

[0018] The fourth section can have a local axial width between 1 mm and 60 mm. The local axial width of the fourth section can be measured locally in the circumferential direction. If the fourth section is arranged in varying axial areas depending on its circumferential position, then, in other words, the axial width is not measured between axial extreme positions located at different circumferential positions, but rather for each circumferential position.

[0019] The fourth section can connect the first and third sections. According to a particularly preferred embodiment of the design described here, the first, fourth, and third sections are wound from a continuous length of material to be wound, wherein the fourth section is wound from a portion of the length to be wound that is positioned between those portions of the length to be wound from which the first and third sections are wound. Preferably, the fourth section is wound in a single layer and in a spiral shape, the pitch of the spiral being greater than the width of the length to be wound, so that gaps remain next to or within the fourth section.In this case, the local axial width of the fourth section can essentially correspond to the width of the length to be wound, in particular the width of the length to be wound divided by the cosine of the helix angle of the spiral shape in the fourth section. The second section can be wound radially above and / or below the fourth section and, through the gaps beside or within the fourth section, contribute to an electrically conductive path through the vehicle tire.

[0020] The vehicle tire can comprise an electrically non-conductive tread, wherein an electrically conductive channel extends radially through the tread. An electrically non-conductive tread can comprise at least either a cap or a base, each of which is based on an electrically non-conductive rubber compound. Preferably, both the cap and the base of the tread are optimized for low rolling resistance and, conversely, are both based on electrically non-conductive rubber compounds. The electrically conductive channel can extend from a tread surface on a radial upper surface of the cap, through the cap and the base, to a radial lower surface of the base and can extend over the entire circumference of the vehicle tire. In particular, the electrically conductive channel can be configured as a known carbon center beam.

[0021] The electrically conductive channel can make electrical contact with the second section of the coil bandage, and in particular, make direct mechanical contact with it. Conventional carbon center beams are preferably arranged in the axial vicinity of the tire equator, resulting in a synergistic advantage when the second section of the coil bandage is located in the equatorial region of the vehicle tire, and especially when the tire equator plane intersects the second section. The electrically conductive channel can be in mechanical contact with the second section over the entire circumference of the vehicle tire. Alternatively, the mechanical contact can be interrupted at certain points, for example, by the fourth section of the coil bandage, whereby in particular one or more windings of the fourth section can cross the overlapping area between the electrically conductive channel and the second section.

[0022] The second section can have an axial width between 1% and 60% of the axial width of the vehicle tire, and preferably between 1% and 30% of the axial width of the vehicle tire. This allows for a good compromise between sufficient conductivity and low rolling resistance in the vehicle tire.

[0023] For the coiled bandage, material strips can be used as the lengths to be wound onto the coil, preferably between 5 mm and 50 mm wide. Alternatively or additionally, the coiled bandage can be partially or completely wound from rubberized individual cords.

[0024] The coil bandage can be wound essentially in a single layer and spirally in both the first and second sections. An essentially single-layer coil bandage can also be partially double-layered at the beginning and / or end of a section, for example, as part of a so-called runstop. The second section can be wound with between 0.5 and 20 turns, and preferably with between 1 and 10 turns. Generally, lower turn counts may be necessary and advantageous when using wider coil lengths compared to narrower coil lengths, for example, if a second section of a specific width is desired. Regardless of this, a specific turn count can be selected with regard to the stability of the coil pattern and / or the practical requirements of a manufacturing process.

[0025] Alternatively, the coil bandage can be wound in two or more layers. In this case, the second section should extend continuously over the entire radial depth of the coil bandage. This ensures an electrical bridge that completely penetrates the coil bandage radially. A continuous second section of two or more layers can be achieved by winding the corresponding windings radially in direct contact with each other, creating an electrically conductive path perpendicular to a longitudinal dimension of the wound length and between radially stacked windings. It may be sufficient if the second section extends continuously over the entire radial depth of the coil bandage only in partial regions of its circumferential and / or axial extent.The second section can be bounded or interrupted radially below, above, and / or in the middle by sections with non-conductive rubber compounds, apart from the aforementioned sub-areas. Such a bounding or interrupting section could, in particular, be the fourth section of the coil bandage. Alternatively, incomplete coil patterns can be chosen for the second section, for example, a spiral with a pitch exceeding the width of the length to be coiled, in which case the electrically conductive path would run mainly along the longitudinal extent of the coiled length.

[0026] Vehicle tires designed according to the invention are tires of any design, in particular radial tires, and tires of any type, in particular pneumatic tires for motor vehicles, such as passenger cars, light trucks or commercial vehicles.

[0027] The vehicle tire can include a sidewall, which may be based on an electrically non-conductive rubber compound. The vehicle tire preferably includes a belt assembly over which the coiled bandage is wound. According to one embodiment, the belt assembly may be based on an electrically conductive rubber compound. There may be electrical contact between the radial underside of the second section of the coiled bandage and the radial upper side of the belt assembly. This electrical contact may be accompanied by mechanical contact and may extend over the entire length of the second section of the coiled bandage in the axial and / or circumferential direction.Alternatively, the electrical and / or mechanical contact between the belt bandage and the coil bandage can be interrupted at certain points, for example, by the fourth section of the coil bandage, in particular by a winding of the fourth section that crosses radially below the second section. The vehicle tire can comprise a carcass, which may be based on an electrically conductive rubber compound. Overall, a continuous electrically conductive path can run through the tread, the belt bandage, the belt bandage, and the carcass. In this manner, electrical charge can be transferred and dissipated between a rim, which may be conductively connected to the carcass, and a road surface, which may be in contact with the electrically conductive channel through the tread.The electrically conductive paths between the second section of the coiled bandage and the road surface on one side, and between the second section of the coiled bandage and the rim on the other, can also be implemented using alternative structures. For example, the belt reinforcement and / or the carcass can be based on electrically non-conductive rubber compounds, with electrically conductive paths being created, for example, using electrically conductive yarns.

[0028] Overall, the specific resistances and dimensions of the assemblies defining the electrically conductive path between the road surface and the rim should be dimensioned such that the electrically conductive path has a resistance of less than 1×10 10< Ω, preferably less than 1×10 8< Ω, and more preferably less than 1×10 6< Ω.

[0029] The invention further relates to a method for manufacturing a belt bandage in a vehicle tire, wherein a belt assembly for a vehicle tire and a first and second length to be wound onto a coiled bandage are provided, the lengths to be wound onto the coiled bandage comprising reinforcing elements embedded in rubber compounds. A first section of the coiled bandage is wound onto the belt assembly from the first length to be wound onto the coiled bandage, wherein the rubber compound of the first length to be wound onto the coiled bandage is electrically non-conductive. A second section of the coiled bandage is wound onto the belt assembly from the second length to be wound onto the coiled bandage, wherein the rubber compound of the second length to be wound onto the coiled bandage is electrically conductive.

[0030] By using two coiled lengths, both comprising reinforcement carriers but with different rubber compounds, a surprisingly simple method is created for producing a continuously rigid belt bandage with individually dimensionable sections to optimize rolling resistance or electrical conductivity.

[0031] Preferably, the first length to be wound is wound by a first winding head and the second length by a second winding head. This makes the provision and winding of the lengths particularly easy to handle.

[0032] According to one embodiment, a third section of the coiled bandage can be wound onto the first length to be wound. This allows for particularly efficient use of the tools and materials required for manufacturing the belt bandage. Alternatively or additionally, a fourth section of the coiled bandage can be wound onto the first length to be wound. In this case, the fourth section can be wound onto a portion of the first length that connects the first and third sections.

[0033] According to one embodiment, the method is subdivided into the following steps: i) the first section of the coil bandage is wound up; ii) the first length to be wound up is cut; iii) the first winding head is moved axially to a gap width distance from an axial edge of the first section; iv) starting from the position set in step iii), the third section of the coil bandage is wound up; v) the second section of the coil bandage is wound up between the first and third sections across the gap width.

[0034] According to a particularly simple sub-formation of the embodiment described above, in step i) the first section of the coiled bandage can be wound spirally from a first tire shoulder towards the tire equator, wherein in step iv) the third section of the coiled bandage is wound spirally from the position set in step iii) to a second tire shoulder, and wherein in step v) the second section of the coiled bandage is wound spirally. The described sub-formation is suitable for producing a belt bandage that is essentially single-layered and wound spirally. Alternative winding patterns can also be implemented within the framework of the described embodiment.For example, the first and / or the second length to be wound can be wound with an overlap relative to itself; alternatively or additionally, the second length to be wound can be wound with an overlap to the first and / or the third section. The embodiment can also be modified by integrating one or more further steps into the process in addition to the described steps i) to v) and / or omitting one or more steps from the described steps i) to v). The method according to the invention can also be successfully implemented outside the described embodiment, with entirely different steps.

[0035] According to an alternative embodiment, the method is subdivided into the following steps: a) The first section is wound from a first length to be wound from a first tire shoulder to a first axial position; b) The fourth section is wound from the first length to be wound between the first axial position and a second axial position in such a way that gaps remain uncovered by the fourth section in an area spanned by the axial and circumferential directions between the first and second axial positions; c) The third section is wound from the first length to be wound between the second axial position and a second tire shoulder.

[0036] The first axial position can be located between a tire equator and a first tire shoulder, and / or the second axial position can be located between the tire equator and a second tire shoulder. According to the first variant, the second section of the coil bandage can be wound onto the belt bandage from a second length to be wound onto the belt bandage between the first and second axial positions before the described steps a) to c). According to the second variant, the second section can be wound onto the belt bandage and the fourth section of the coil bandage from the second length to be wound onto the belt bandage after the described steps a) to c) between the first and second axial positions.

[0037] In the described manner, the first length to be wound can advantageously be wound in a continuous winding process from the first tire shoulder to the second tire shoulder without cutting the first length. According to the first described variant for winding the second section, contact can be established through the gaps remaining next to and / or within the fourth section between a conductive channel arranged radially above the wound bandage, in particular a carbon center beam, and the second section. According to the second described variant, contact can be established through the gaps in the fourth section between the belt reinforcement arranged radially below the wound bandage and the second section. In this way, an electrically conductive path through the tire can be ensured.The fourth section can be wound incompletely within the described step b), for example, by keeping the slope of a spiral winding motion greater than the width of the first length to be wound, whereby the first length to be wound can cross the tire equator in the area of ​​the fourth section.

[0038] The method can be further developed with additional features, which are described in connection with the vehicle tire according to the invention. The vehicle tire can be further developed with additional features, which are described in connection with the method according to the invention.

[0039] The invention is described below by way of example with reference to the accompanying drawings and advantageous embodiments. The drawings show: Figure 1schematically a simplified circuit diagram relating to an electrical path through a vehicle tire according to an embodiment of the invention, Figure 2 schematically two views of a coil diagram according to an embodiment of the invention, Figure 3 schematically a view of a coil diagram according to a further embodiment of the invention, Figure 4 schematically a view of a coil diagram according to an alternative embodiment of the invention.

[0040] Figure 1Figure 1 shows a schematic circuit diagram of the electrical path through a vehicle tire, between a road surface 11 and a rim 16 of the vehicle tire. Each of the rectangles represents the electrical resistance of a component within the vehicle tire. A cross next to a rectangle indicates that this component is based on a non-conductive rubber compound, and therefore the component is not a significant part of the electrical path through the vehicle tire. A check mark next to a rectangle indicates that this component is based on an electrically conductive rubber compound, and therefore the component is a significant part of the electrical path through the vehicle tire.

[0041] The vehicle tire comprises a tread strip, which includes a cap 4a and a base 4b, wherein cap 4a and base 4b contain rubber compounds optimized for rolling resistance that are electrically non-conductive. The tread strip 4a, 4b is bridged by an electrically conductive channel 5, wherein, in the illustrated embodiment, the electrically conductive channel is designed as a carbon center beam that electrically bridges both cap 4a and base 4b. According to the invention, the coil bandage 10 is divided into a first and a second section 1, 2, wherein the first section 1 is electrically non-conductive and contains a rubber compound optimized for rolling resistance. The second section 2 contains an electrically conductive rubber compound and establishes an electrical connection between the carbon center beam 5 and a belt assembly 7, wherein, in the illustrated embodiment, the belt assembly 7 is based on an electrically conductive rubber compound.A sidewall 13 is based on an electrically non-conductive rubber compound optimized for rolling resistance, wherein a carcass 12 is based on an electrically conductive rubber compound and creates an electrical bridge between the belt reinforcement 7 and an electrically conductive rim strip 15, which in turn is electrically connected to a rim 16. Due to the embodiment according to the invention with two sections 1, 2, the coil bandage 10 can, on the one hand, contribute to a low rolling resistance of the vehicle tire; on the other hand, for example, according to the one in . Figure 1 The depicted electrical path is specifically designed to implement an electrical bridge in the coil bandage 10.

[0042] Figure 2The upper part of the image shows a coil bandage 10, with the circumference unwound over 360° shown vertically in the image plane and the transverse extent of the coil bandage 10 shown horizontally. The coil bandage 10 is divided into three sections 1, 2, 3, the respective axial extents of which are indicated by arrows and delimited by dashed lines in the figure. The first and third sections 1, 3 axially delimit the second section 2 from two sides. The second section 2 is located in the axial center, in the region of a tire equator, and can be in radial contact with a carbon center beam 5 at the top (see figure). Figure 1 ).

[0043] The coiled tire bandage 10 is wound from material strips 6, the material strip 6 in the first section 1 of the coiled tire bandage 10 originating from a first length 8 to be wound. The first length 8 to be wound, and thus also the coiled tire bandage 10 in the first section 1, comprises reinforcing elements (not shown) running along the length 8 as cords, which are embedded in an electrically non-conductive rubber compound optimized for rolling resistance. The material strip 6 in the third section also originates from the first length 8 to be wound. Accordingly, the first and third sections 1, 3 are electrically non-conductive and do not significantly contribute to an electrical path through the vehicle tire (see the corresponding marking by crosses).

[0044] The material strip 6 in the second section 2 of the coiled bandage 10 originates from a second length 9 to be wound onto the coil. The second length 9 to be wound onto the coil, and thus also the coiled bandage 10 in the second section 2, comprises, like the first length 9 to be wound onto the coil, reinforcing elements formed as cords, which, unlike those in the first length 8 to be wound onto the coil, are embedded in an electrically conductive rubber compound. Accordingly, the second section 2 is electrically conductive and significantly contributes to the electrical path through the vehicle tire (see the marking by the hook).

[0045] Because both lengths to be wound include 8, 9 reinforcing elements, the entire wound bandage 10 is correspondingly stable. The different rubber compounds contribute to both low rolling resistance and an efficient electrical path within a vehicle tire.

[0046] In the lower part of the image Figure 2Figure 10 shows a sectional view of the coil bandage 10 in a plane spanned by the axial and radial directions. Accordingly, the coil bandage is essentially wound in a single layer; only at the axial edges are the material strips 6 of the first length 8 to be wound wound partially double-layered in so-called run stops. The movements of a first and second winding head to be performed during the production of the coil bandage 10 shown are schematically illustrated by the paths designated by reference symbols 17, 18, and 19. Accordingly, the process begins by winding the first length 8 to be wound from the first winding head from the Figure 1Starting from the axial side shown on the left, the first length 8 to be wound onto the tire is wound along path 17 towards the tire's equator. At the boundary between the first section 1 and the second section 2, the first length 8 to be wound is cut, and the first winding head, without unwinding, is moved across the tire's equator to the boundary between the second section 2 and the third section 3. From here, the first length 8 to be wound onto the tire is wound from the first winding head along path 18 towards the axial side shown on the right in the figure. Subsequently, the second length 9 to be wound onto the tire is wound from the second winding head along path 19 to complete the wound bandage 10 with the second section 2.

[0047] Figure 3 shows an alternative embodiment of a coil bandage 10 according to the invention in a similar view to that shown in the lower part of the image. Figure 2. At the bottom, a belt bandage 7 is also shown, over which the coil bandage 10 is wound in two layers from material strips 6. Starting at the boundary between a first section 1 and a second section 2, a first length 8 to be wound is unwound from a first spool head along a path 20. This is done in the direction of a Figure 2On the axial side shown on the left, a first layer of the first section 1 is wound onto the spool; then the orientation is reversed and a second layer is wound onto the spool in the direction of the starting point. Back at the boundary between the first section 1 and the second section 2, the first length 8 to be wound onto the spool is cut, and the first spooling head is moved, without unwinding, across the tire equator to the boundary between the second section 2 and the third section 3. The third section 3 is wound onto the spool along path 21 analogously to the first section 1, also from the first length 8 to be wound onto the spool, and using the first spooling head. The second section 2 is wound onto the spool along path 22 in a double layer from a second length 9 to be wound onto the spool, using a second spooling head.The material strip 6 of the second length 9 to be wound on is based on an electrically conductive rubber compound and is wound radially throughout in the second section 2, so that an electrical bridge is formed between the belt assembly 7 based on an electrically conductive rubber compound and a section 2. Figure 2 The Carbon Center Beam 5, which is not shown and is to be arranged radially above the second section 2, can be realized.

[0048] Figure 4 shows an alternative embodiment of a coil bandage 10 according to the invention in a similar view to that shown in the Figure 2The coil bandage 10 is divided into four sections 1, 2, 3, 23, the arrangement of which is indicated in the figure by arrows and delimited by dashed lines, wherein the first and third sections 1, 3 axially delimit the second section 2 from two sides, and wherein the fourth section 23 runs transversely across the second section 2 between the first and third sections 1, 3. The first section 1 extends between a first tire shoulder and a first axial position 24, wherein the first tire shoulder and the first axial position 24 are arranged relative to a first side of a tire equator. The second section 2 and the fourth section 23 extend between the first axial position 24 and a second axial position 25.The third section 3 extends between the second axial position 25 and a second tire shoulder, wherein the second tire shoulder and the second axial position 25 are arranged to a second side of the tire equator.

[0049] The coiled bandage 10 is wound from material strips 6; the material strip 6 in the second section 2 of the coiled bandage 10 originates from a second length 9 to be wound. The second length 9 to be wound, and thus also the coiled bandage 10 in the second section 2, comprises reinforcing elements formed as cords, which are embedded in an electrically conductive rubber compound. Accordingly, the second section 2 is electrically conductive and contributes significantly to the electrically conductive path through the vehicle tire (see the marking by the hook). In the illustrated embodiment, the second section 2 is located directly radially above a Figure 4wound up on an electrically conductive belt bandage (not shown).

[0050] The material strip 6 in the first section 1 of the coiled bandage 10 originates from a first length 8 to be wound onto the coil. The first length 8 to be wound onto the coil, and thus also the coiled bandage 10 in the first section 1, comprises reinforcing elements (not shown) running along the length 8 as cords, which are embedded in an electrically non-conductive rubber compound optimized for rolling resistance. The material strip 6 in the third section also originates from the first length 8 to be wound onto the coil. Accordingly, the first and third sections 1, 3 are electrically non-conductive and do not significantly contribute to an electrical path through the vehicle tire (see the corresponding marking by crosses).The material strip 6 in the fourth section 23 also originates from the first length 8 to be wound up, with the material strip 6 from the first length 8 being wound up from the first section 1 through the fourth section 23 to the third section without interruption. For better differentiation from the second section 2, the fourth section 23 is shown hatched. The fourth section 23 lies radially above the second section 2, runs obliquely across the second section 2 in the axial and circumferential directions, and crosses the tire equator. If, in the region of the tire equator, a [missing information] is located radially above the winding band 10... Figure 4The carbon center beam 5 (not shown) can be arranged so that it can contact the second section 2 in the area of ​​the gaps remaining next to the fourth section 23. By winding the fourth section 23 together with the first and third sections 1, 3, the embodiment according to Figure 4 They can be manufactured particularly efficiently. Because the fourth section 23 is wound incompletely in the area of ​​the second section, the advantages of the embodiments according to are retained. Figures 2 and 3 insofar as the second section 2 can come into electrical contact with other electrically conductive components of the vehicle tire from the radial bottom and top.

[0051] In the lower part of the image Figure 4A cross-sectional view of the coiled bandage 10 is shown in a plane spanned by the axial and radial directions. Accordingly, the coiled bandage is essentially wound in a single layer in the area of ​​the first and second sections 1, 3; only at the axial edges, in the area of ​​the tire shoulders, are the material strips 6 of the first length 8 to be wound on top of each other in so-called run stops, in some places double-layered sections. The movements of a first and second winding head to be carried out in the production of the coiled bandage 10 shown are schematically illustrated by the paths designated by reference symbols 26, 27, 28. Accordingly, the second length 9 to be wound on is wound spirally and without gaps from the second winding head between the first and second axial positions 24, 25. Subsequently, the first length 8 to be wound on is wound from the first winding head by the Figure 4Starting from the first tire shoulder shown on the left, the material is wound spirally and continuously along path 26 towards the tire equator. At the first axial position 24, the pitch of the spiral winding motion is increased to wind the fourth section 23, still fed from the first length 8 to be wound and from the first winding head, intermittently over the second section 2. At the second axial position 25, the pitch of the winding motion is decreased again to wind the third section 3 along path 27 towards the point shown in the Figure 4The second tire shoulder shown on the right is wound spirally and without gaps. In this way, the first, fourth, and third sections 1, 3, 23 can be wound continuously from a first length 8 in a single winding head without significantly restricting the function of the second section 2 as an electrical bridge through the winding band 10. Reference symbol list

[0052] 1. First section 2. Second section 3. Third section 4a. Tread cap 4b. Tread base 5. Electrically conductive channel / Carbon center beam 6. Material strip 7. Belt assembly 8. First length to be wound 9. Second length to be wound 10. Winding bandage 11. Roadway 12. Carcass 13. Sidewall 15. Rim strip 16. Rim 17. Path of the first winding head for winding the first section 18. Path of the first winding head for winding the third section 19. Path of the second winding head for winding the second section 20. Path of the first winding head for winding the first section 21. Path of the first winding head for winding the third section 22. Path of the second winding head for winding the second section 23. Fourth section 24. First axial position 25. Second axial position 26. Path of the 27 Path of the first winding head for winding the first section 28 Path of the second winding head for winding the second section

Claims

1. Vehicle tyre having a belt bandage in the form of a wound bandage (10), wherein the wound bandage (10) comprises strengthening members embedded into a rubber mixture, wherein the rubber mixture in a first portion (1) of the wound bandage (10) is electrically non-conductive, characterized in that the rubber mixture in a second portion (2) of the wound bandage (10) is electrically conductive.

2. Vehicle tyre according to Claim 1, characterized in that the rubber mixture in the first portion (1) has better suitability for minimization of a rolling resistance of the vehicle tyre than the rubber mixture in the second portion (2).

3. Vehicle tyre according to either of Claims 1 and 2, characterized in that the rubber mixture in a third portion (3) is electrically non-conductive, wherein the second portion (2) is delimited by the first and third portions (1, 3) on respective axial sides.

4. Vehicle tyre according to one of Claims 1 to 3, characterized in that the rubber mixture in a fourth portion (23) is electrically non-conductive, wherein at least a part of the fourth portion (23) is arranged radially below and / or above the second portion (2), wherein the fourth portion (23) runs in such a way that gaps remain in the axial direction and / or in the circumferential direction next to that part of the fourth portion (23) which is arranged radially below and / or above the second portion (2), wherein the gaps are filled by the second portion (2).

5. Vehicle tyre according to one of Claims 1 to 4, characterized in that a tyre equatorial plane intersects the second portion (2).

6. Vehicle tyre according to one of Claims 1 to 5, characterized in that the vehicle tyre comprises a tread (4a, 4b) based on an electrically non-conductive rubber mixture, wherein an electrically conductive channel (5) extends radially through the tread (4a, 4b).

7. Vehicle tyre according to Claim 6, characterized in that the electrically conductive channel (5) electrically conductively contacts the second portion (2) of the wound bandage (10).

8. Vehicle tyre according to one of Claims 1 to 7, characterized in that the second portion (2) has an axial width of between 1% and 60% of an axial width of the vehicle tyre, and preferably of between 1% and 30% of the axial width of the vehicle tyre.

9. Vehicle tyre according to one of Claims 1 to 8, characterized in that material strips (6) used for the wound bandage (10) have a width of between 5 mm and 50 mm, and / or in that the wound bandage (10) comprises single wound-on rubberized cords.

10. Vehicle tyre according to one of Claims 1 to 9, characterized in that, in the first and second portions (1, 2), the wound bandage (10) is respectively wound on substantially as a single ply and in the shape of a spiral, wherein the second portion (2) is wound on with 0.5 to 20, and preferably with 1 to 10, revolutions.

11. Method for producing a belt bandage in a vehicle tyre, wherein a belt assembly (7) and a first and a second length (8, 9) to be wound on to form a wound bandage (10) are provided, wherein the lengths (8, 9) to be wound on comprise strengthening members embedded into rubber mixtures, wherein a first portion (1) of the wound bandage (10) is wound onto the belt assembly (7) from the first length (8) to be wound on, wherein the rubber mixture of the first length (8) to be wound on is electrically non-conductive, characterized in that a second portion (2) of the wound bandage (10) is wound onto the belt assembly (7) from the second length (9) to be wound on, wherein the rubber mixture of the second length (9) to be wound on is electrically conductive.

12. Method according to Claim 11, characterized in that the first length (8) to be wound on is wound on by a first winding head and the second length (9) to be wound on is wound on by a second winding head.

13. Method according to either of Claims 11 and 12, wherein a third portion (3) of the wound bandage (10) and / or a fourth portion (23) of the wound bandage (10) are / is additionally wound on from the first length (8) to be wound on.

14. Method according to Claims 12 and 13, wherein the method is subdivided into the following steps: i) the first portion (1) of the wound bandage (10) is wound on; ii) the first length (8) to be wound on is severed; iii) the first winding head is brought axially to a point at a distance of a gap width from an axial edge of the first portion (1); iv) starting from the position set in step iii), the third portion (3) of the wound bandage (10) is wound on; v) the second portion (2) of the wound bandage (10) is wound on between the first and third portions (1, 3) across the gap width.

15. Method according to Claims 12 and 13, wherein the method is subdivided into the following steps: i) the first portion (1) of the wound bandage (10) is wound on from a first tyre shoulder as far as a first axial position (24); ii) the fourth portion (23) of the wound bandage (10) is wound on from the first length (8) to be wound on between the first axial position (24) and a second axial position (25) in such a way that, in an area spanned by the axial and circumferential directions between the first and second axial positions, gaps not covered by the fourth portion (23) remain; iii) the third portion (3) is wound on from the first length (8) to be wound on between the second axial position (25) and a second tyre shoulder; according to a first alternative, the second portion (2) is wound onto the belt assembly (7) between the first and second axial positions (24, 25) before steps i) to iii); according to a second alternative, the second portion (2) is wound onto the belt assembly (7) and the fourth portion (23) of the wound bandage (10) from the second length (9) to be wound on between the first and second axial positions (24, 25) after steps i) to iii).