Tire having an improved tire abrasion profile

Abstract

The present invention relates to a pneumatic tire having a carcass layer, a belt layer and a tread rubber, wherein: the belt layer has a circumferential reinforcement layer which is embedded between two other belt plies, is formed by steel cords and has a belt angle within a range of ± 5°; in the region of its edges, the circumferential reinforcement layer has a number of ends of the belt cords forming the circumferential reinforcement layer, which number is at least 30% greater than the number of ends of the belt cords forming the circumferential reinforcement layer in the central region of the circumferential reinforcement layer at the tire equator. The present invention also relates to methods for producing belt packages having circumferential reinforcement layers designed in this way, to methods for producing corresponding pneumatic tires, and to the use of circumferential reinforcement layers designed in this way for optimizing the tire contact surface and / or the tire abrasion profile.

Description

[0001] 202405654

[0002] 1

[0003] Description

[0004] Tires with improved tire wear pattern

[0005] Description of the invention

[0006] The present invention relates to a pneumatic tire comprising a carcass layer and a belt layer, the latter having a circumferential reinforcement layer formed between other belt layers by steel cords, with a belt angle within a range of ± 5°, wherein the circumferential reinforcement layer has, in the region of its edges, a number of ends of the belt cords constituting the circumferential reinforcement layer that is at least 30% greater than the number of ends of the belt cords constituting the circumferential reinforcement layer in the central region of the circumferential reinforcement layer at the tire equator. The present invention further relates to methods for manufacturing belt packages with circumferential reinforcement layers of this type, methods for manufacturing corresponding pneumatic tires, and the use of circumferential reinforcement layers of this type for optimizing the tire contact patch and / or the tire wear profile.

[0007] State of the art

[0008] In tire design, a key objective is to create a tire with a uniform contact patch when mounted on the rim. This prevents areas of the tire from experiencing excessive wear. Completely eliminating wear is generally neither possible nor desirable, as this would necessitate excessive tire stiffness, negatively impacting traction. Therefore, the pneumatic tire design must ensure that, when inflated and rotating, it maintains the flattest possible contact patch with the ground. Furthermore, the design should compensate for tensile forces resulting from a non-circular tire cross-section as much as possible.

[0009] 2. These differences must be balanced. Since the wear problem increases with increasing load on the tire, and tires for high loads are generally designed to be wider than those for lower loads, such a balance is particularly important for truck and bus tires.

[0010] A tire construction with a belt ply in which the cords are arranged at an angle of 0° to ± 5° with respect to the tire equator (which here denotes the line of intersection of a plane perpendicular to the tire axis through the center of the tire tread), and in which this belt ply is arranged between two cross belts, is described in EP 2 191 983 B1. This tire construction is intended to produce a tire with improved durability, while also reducing uneven wear across the tire tread.

[0011] DE 2909086 A1 describes tires for motor vehicles with a carcass layer and a belt layer formed from two cross belts and an additional outer belt layer, which are made of cords with an increased elongation at break in the range of 4 to 8%, and wherein the cords are arranged at an angle of 0° with respect to the longitudinal direction of the tire. In the area of ​​the edges of the belt layer with the cords oriented at an angle of 0°, either the density of the cords is increased or, with the same cord density, the thickness of the cords is increased. In this way, a tire with a small number of belt layers is intended to provide good driving stability and high resistance to tensile and compressive stresses within the tire.

[0012] DE 102012 214 866 A1 describes a pneumatic tire with a carcass and belt layer comprising multiple belt layers and a layer arranged thereon, formed from band-shaped elements. Each band-shaped element is formed from multiple steel cord threads arranged at equal intervals and embedded in a rubber matrix. According to DE 102012 214 866 A1, gaps are provided between the band-shaped elements in the center of the tire.

[0013] 3 while in the area of ​​the tire edge the band-shaped elements are arranged either precisely fitted to each other or diagonally overlapping, so that there are more steel cord threads in this area than in the area of ​​the tire equator.

[0014] EP 2657047 B1 and DE 69106926 T2 describe pneumatic tires in which a layer of strips containing several parallel cords is applied to the belt plies. In the central region of the tire, the strips are arranged in a single layer with spacing between them, while in the edge region, the strips are arranged in two layers, overlapping in a Z-shape. This results in greater reinforcement of the tire in the edge region than in the center. In the tires described in EP 2657047 B1 and DE 69106926 T2, the layer formed by the strips extends beyond the underlying belt plies.

[0015] DE102015204701 A1 describes a tire construction comparable to EP 2657047 B1, wherein, in the area of ​​the edge of the layer formed by the strips, a structure is formed with a lower strip, a Z-shaped strip partially arranged above it, and an upper strip placed over the lower part of the Z-shaped strip (structure in the form shown). Such a construction is proposed to improve driving characteristics.

[0016] Regarding the aforementioned problem of improving tire durability through more uniform wear behavior, further improvements are needed. The present invention addresses this need.

[0017] Description of the invention

[0018] In the investigations underlying this invention, it was found that a more uniform contact surface of a pneumatic tire in the driving state can be achieved by including a circumferential reinforcement layer formed from steel cords between other belt layers in the belt layer, which provides a belt angle within a range of ± 5° with respect to 202405654

[0019] 4. The circumferential reinforcement layer has a number of ends of the belt cords constituting the circumferential reinforcement layer in the region of its edges that is significantly greater than the number of ends of the belt cords constituting the circumferential reinforcement layer in the central region of the circumferential reinforcement layer at the tire equator. Compared to a circumferential reinforcement layer formed from uniformly reinforced steel cords, such a configuration of the circumferential reinforcement layer ensures a significantly more uniform free longitudinal rolling force, resulting in more uniform contact forces of the tire on the road surface and, consequently, more uniform wear behavior during tire use.

[0020] According to a first aspect, the present invention therefore relates to a pneumatic tire with a carcass layer, a belt layer arranged on the outside of the carcass layer, and a tread rubber arranged on the outside in the tire radial layer of the belt layer, wherein the belt layer has a circumferential reinforcement layer embedded between other belt layers, the belt angle having a belt angle within a range of ± 5° with respect to the tire circumferential direction, and wherein the circumferential reinforcement layer is formed by steel cords, and wherein the circumferential reinforcement layer has a number of ends of the belt cords constituting the circumferential reinforcement layer in the region of their edges that is at least 30% greater than the number of ends of the belt cords constituting the circumferential reinforcement layer in the central region of the circumferential reinforcement layer at the tire equator.Due to the higher number of ends, there are consequently more steel cords in this area (so that the "steel cord density" is 30% or more higher here than in the middle area of ​​the circumferential reinforcement layer), which reinforce the pneumatic tire in this area.

[0021] In the context of the invention described herein, the term "circumferential reinforcement layer" preferably refers to a layer with substantially uniform thickness, i.e., the layer exhibits deviations across its entire width. 202405654

[0022] 5. The thickness in dtex of the steel cords forming the layer and / or the cross-sectional area of ​​the steel cords varies by a maximum of ± 20%. The layer is generally formed by the cords themselves and rubber material arranged between and around these cords. This also includes embodiments in which very few cords are present in the central region of the circumferential reinforcement layer, as well as the limiting case where no steel cords are present in the central region of the circumferential reinforcement layer. In this case, the thickness of the circumferential reinforcement layer and its uniformity are determined solely by the thickness of the steel cords in the edge regions of the circumferential reinforcement layer.

[0023] A layer that does not meet the characteristic of "essentially uniform thickness of the circumferential reinforcement layer" is, on the other hand, a layer formed from steel cords of different thicknesses in the edge and center areas, and a layer in which steel cords are arranged in more than one plane in one part of the layer and in only one plane in another part. All steel cords associated with the circumferential reinforcement layer have a belt angle within a range of ± 5° with respect to the tire's circumferential direction.

[0024] The term "belt cords" refers to the cords assigned to the respective belt, while "steel cords" indicates the material from which the cords are made. When belt cords of the circumferential reinforcement layer are mentioned above or below, these are steel cords, so the terms are used synonymously when referring to the circumferential reinforcement layer.

[0025] For the number of ends in the edge region of the circumferential reinforcement layer and in its central region, it is advantageous to set a larger difference, i.e., if the number of ends of the belt cords constituting the circumferential reinforcement layer in the region of its edges is more than 30% greater than the number of ends of the belt cords constituting the circumferential reinforcement layer in the central region of the circumferential reinforcement layer, for example by 202405654

[0026] 6. at least 50% larger. A further preferred difference is at least 100% larger, in particular at least 150% larger, and even more preferably at least 200% larger. An upper limit cannot be specified here because, in the limiting case, the circumferential reinforcement layer in the central region cannot contain any belt cords. However, if the circumferential reinforcement layer in the central region does have belt cords, then the number of ends of the belt cords constituting the circumferential reinforcement layer in the region of their edges is preferably no more than 800% larger, and more preferably no more than 600% larger, than the number of ends of the belt cords constituting the circumferential reinforcement layer in the central region of the circumferential reinforcement layer.As previously mentioned, the circumferential reinforcement layer has a substantially uniform thickness, with the individual steel cords of this layer having a thickness in dtex and / or a cross-sectional area that deviates by no more than ± 20% from the thickness of all other steel cords in the circumferential reinforcement layer. The advantage of such a configuration is that the circumferential reinforcement layer can be formed from a single cord material, thus minimizing manufacturing costs.

[0027] The steel cords forming the circumferential reinforcement layer preferably have an elongation at break of less than 4.5%, and more preferably less than 4%. It is particularly preferred that the elongation at break be at least 1%, and especially at least 2%. In one embodiment, the elongation at break is between 2% and 3%. In another embodiment, the elongation at break is more than 3% and less than 4.5%. Here, elongation at break refers to the property of the cords as contained in the tire, and as it can be determined, for example, by extracting the cords from the tire and subsequently measuring them. According to the invention, the elongation at break is to be determined by measurement in accordance with ASTM D 4975.

[0028] Another property relevant to the steel cords of the belt cords from which the circumferential reinforcement layer is configured is elongation. This should be 202405654

[0029] 7. According to the invention, the thickness of the belt cords, which make up the circumferential reinforcement layer, is preferably not less than 1.0% and not more than 2.5% when the belt cords from which the circumferential reinforcement layer is configured are subjected to a tensile load of 150 N to 500 N. Such steel cords exhibit a good elongation rate when a light load is applied, compared to ordinary steel wire, so that they are resistant to the loads applied to the circumferential reinforcement layer during the time from manufacture to use of the tire. In this way, damage to the circumferential reinforcement layer can be suppressed for a long service life.

[0030] In a preferred embodiment, the circumferential reinforcement layer, defined from the tire equator to the tire shoulder, has two regions with a uniform number of ends of the belt cords constituting the circumferential reinforcement layer across each region. That is, in both edge regions of the circumferential reinforcement layer, the number of ends of the belt cords constituting the circumferential reinforcement layer is the same, while in the central region, as described above, the number of ends of the belt cords constituting the circumferential reinforcement layer is lower than in the edge region. In another embodiment, the edge regions differ with respect to the number of ends of the belt cords constituting the circumferential reinforcement layer, with the number of ends in the central region being at least 30% lower than the number of ends in the edge region, which has the lower number of ends.

[0031] In the central region of the circumferential reinforcement layer, the steel cords are therefore arranged with a greater spacing between them. The specification "greater spacing" also includes the case where no steel cords are present in the central region of the circumferential reinforcement layer. Such an embodiment is particularly preferred in the context of the invention described here because it allows for a high degree of uniformity of the tire's contact patch with a substrate. 202405654

[0032] 8

[0033] Regarding the specification "defined from the tire equator to the tire shoulder", the "central area" in the aforementioned context refers only to the part of the central area of ​​the circumferential reinforcement layer that is located on one side of the tire equator (the entire central area of ​​the circumferential reinforcement layer therefore results from the central area parts on one and the other side of the tire equator).

[0034] In this case, the respective "areas" are determined by the constant distance between the ends of the tire cords across the area, i.e., the "area" ends where the distance between the ends of the tire cords changes abruptly (i.e., to a value that differs by at least 20%).

[0035] In another embodiment, the circumferential reinforcement layer, defined from the tire equator to the tire shoulder, has three regions, each with a uniform number of ends of the belt cords constituting the circumferential reinforcement layer across its respective region. It is preferred that regions located at the edge of the circumferential reinforcement layer have the highest number of ends of the belt cords constituting the circumferential reinforcement layer, and that the region adjacent to the tire equator (= central region) has the lowest number of ends of the belt cords constituting the circumferential reinforcement layer. Furthermore, it is preferred that the region between the edge and central regions has a number of ends of the belt cords constituting the circumferential reinforcement layer that is approximately half (i.e.,40 to 60%) of the sum of the number of ends of the belt cords constituting the edge and middle area of ​​the circumferential reinforcement layer.

[0036] In a further embodiment, the central region differs from the edge region in that the steel cords are arranged with equal spacing in the edge region, and the central region begins where the number of ends of the belt cords constituting the circumferential reinforcement layer decreases compared to the number at the edges. This decrease can occur continuously towards the tire's equator, i.e., at the transition from the edge.

[0037] 9. Towards the center area, there is a smaller number of steel cord ends, which decreases further and further towards the tire equator.

[0038] According to the invention, the width of the edge areas is preferably 15 to 40% and particularly 20 to 35% of the total width of the circumferential reinforcement layer. With respect to the total tire width, a ratio of the width of the edge areas of the circumferential reinforcement layer of preferably 8 to 25% and more preferably 10 to 20% can be specified.

[0039] For the pneumatic tires according to the invention, it is cumulatively or alternatively advantageous if the circumferential reinforcement layer in the area of ​​the edge has a number of the ends of the belt cords constituting the circumferential reinforcement layer that are uniform over a distance of 20 to 50 mm and preferably 30 to 50 mm.

[0040] Regarding the actual number of steel cord ends comprising the circumferential reinforcement layer in the edge region, the pneumatic tires according to the present invention are not subject to any relevant limitations, except that when using conventional steel cords, a maximum number of ends is determined by the thickness of the cords. For example, when using standard steel cords to produce the circumferential reinforcement layer, only a maximum number of ends of approximately 64 per 100 mm can be achieved, with the cords in this case being arranged in contact with each other.

[0041] Preferably, the circumferential reinforcement layer has a number of ends of the belt cords constituting the circumferential reinforcement layer of 34 to 60 ends / 100 mm in the area of ​​the edge, more preferably 38 to 55 ends / 100 mm and even more preferably 40 to 52 ends / 100 mm.

[0042] The number of ends of the steel cords that the circumferential reinforcement layer has in the central area is also not subject to any relevant restrictions, with the maximum number of ends here also being limited by the maximum possible 202405654

[0043] 10

[0044] The number of ends in the edge region of the circumferential reinforcement layer and the difference by which the number of ends in the central region should be less than in the edge region are limited. A suitable number of ends of the belt cords constituting the circumferential reinforcement layer in the central region can be specified as 0 to 28 ends / 100 mm, preferably 5 to 25 ends / 100 mm, and more preferably 5 to 16 ends / 100 mm. In a particular embodiment, the number of ends in the central region is "0" ends / 100 mm, i.e., that there are no ends in the central region. In another particular embodiment, the number of ends in the central region is 0 to 16 ends / 100 mm.

[0045] In a further preferred embodiment of the pneumatic tire according to the invention, the circumferential reinforcement layer has a further region between the central region adjacent to the tire equator and the edge region in which the number of ends of the belt cords constituting the circumferential reinforcement layer differs by at least 20% from the number of ends in the region of the edge and at the tire equator. For this region, it is preferred if the number of ends of the belt cords constituting the circumferential reinforcement layer in this region is between 10 and 25 ends / 100 mm and more preferably between 13 and 20 ends / 100 mm. Alternatively or additionally, it is preferred if the further region has a width in the range of 10 to 25% and preferably 15 to 25% cm of the width of the circumferential reinforcement layer.The specified width in this case refers to the width of the edge area; with widths of the given order of magnitude, an advantageous reinforcement and balance of the tire contact profile can be achieved.

[0046] For the pneumatic tires specified according to the invention, it can further be considered preferred that the width of the circumferential reinforcement layer is less than the width of at least two further belt layers present in the belt layer, wherein the two belt layers preferably extend further in both lateral directions relative to the tire equator than the circumferential reinforcement layer. In other words, in this 202405654

[0047] 11

[0048] In this embodiment, the additional belt layers extend further towards the tire shoulder than the circumferential reinforcement layer.

[0049] In a further preferred embodiment of the pneumatic tires according to the invention, these tires have a pair of cross-belts, the belt angles of which, as an absolute value, are not less than 10° and not more than 45° with respect to the tire's circumferential direction, and which have belt angles with opposite signs. The designation "cross-belt" therefore arises from the fact that the individual belt cords of the upper and lower "cross-belts" intersect when viewed from above, due to the opposite signs of the belt angles. For a pneumatic tire equipped with such a pair of cross-belts, it is preferred that the circumferential reinforcement layer is arranged between the first and second cross-belts.

[0050] For the cross-belt layers, it is further preferred that they have a width greater than the width of the circumferential reinforcement layer. For example, the width of the circumferential reinforcement layer can be approximately 70 to 95% of the width of the two cross-belts, or, if the cross-belts have different widths, the width of the narrower cross-belt. A range of 75 to 90% is particularly preferred.

[0051] Another belt layer that may be included in the pneumatic tire according to the invention is a belt layer that has a large belt angle relative to the other belt layers contained in the pneumatic tire (i.e., a belt angle that is greater than the belt angles of the other belt layers contained in the pneumatic tire). Preferably, this belt layer has a belt angle of not less than 45° and not more than 70°. Furthermore, it is preferred for such a belt layer to be laminated on the outside in the tire radial direction of the carcass layer (i.e., this belt layer forms the first belt layer following the carcass layer). The circumferential reinforcement layer is then applied either directly or with one or more intermediate belt layers over this belt layer. 202405654

[0052] 12

[0053] The pneumatic tires according to the invention preferably have an aspect ratio (= ratio of tire height to tire width in %) of 80% or less, whereby in certain cases an aspect ratio of 70% or less may be specified as preferred, an aspect ratio of 60% or less as further preferred and an aspect ratio of 55% or less as even more preferred.

[0054] In a further preferred embodiment, the edge region of the circumferential reinforcement layer extends over the main circumferential grooves of the tire that are furthest from the tire equator (here referred to as the respective main circumferential groove in both lateral directions from the tire equator), i.e., the circumferential reinforcement layer extends beyond these main circumferential grooves toward the tire shoulder. In this case, it is preferred that the point at which the edge region of the circumferential reinforcement layer terminates is spaced at least 2 mm, preferably at least 3 mm, and further preferably about 4 to 8 mm from the edge of the main circumferential grooves when the distance is determined on the tread surface of the tire.

[0055] In a further aspect, the present invention relates to a method for manufacturing a belt pack with several belt layers, one layer of which consists of rubber-coated steel cords. In a first step, the steel cords are coated with rubber, and in a second step, they are wound onto a lower belt layer at an angle of ± 5° with respect to the tire's circumferential direction to form a belt layer. For this purpose, the steel cords are applied to a lower belt layer using a spooling head, the spooling head being operated at different feed rates for the steel cord. This results in steel cords being applied to the belt layer with a smaller distance between two steel cords in the outer regions than in the central region of the belt layer. The resulting combination of belt layers is then combined with at least one further belt layer to form a belt pack. 202405654

[0056] 13

[0057] In a further aspect, the present invention enters into a method for manufacturing a pneumatic tire comprising providing a carcass package, applying a belt package comprising a belt layer manufactured according to the method described above, and a tread layer, wherein the carcass package is provided as the bottom layer, the belt package is applied to this layer, and the tread is applied thereto, and wherein in a final step the pneumatic tire is formed in a mold by vulcanizing the composite of carcass package, belt package and tread layer.

[0058] In a further aspect, the present invention involves the use of a circumferential reinforcement layer with a non-uniform spacing of the ends of the belt cords constituting the circumferential reinforcement layer in a pneumatic tire for optimizing the tire contact area and / or the tire wear profile, wherein the circumferential reinforcement layer has a belt angle within a range of ± 5° with respect to the tire circumferential direction, and wherein the number of ends of the steel cords forming the circumferential reinforcement layer is greater in the edge region (preferably by at least 30% greater) than in the central region of this layer.

[0059] In yet another aspect, the present invention relates to a vehicle, and in particular a truck or bus, which is equipped with at least one pneumatic tire as described above.

[0060] With regard to the foregoing disclosure, it should be noted that embodiments described as preferred or advantageous with respect to one aspect are likewise considered preferred or advantageous with respect to other aspects, provided that no obvious contradictions arise from the combination of features. Likewise, even if not explicitly stated for reasons of brevity, all combinations of embodiments of the aspects are considered combinable and, in their combination, encompassed and described by the disclosure, unless otherwise specified in 202405654.

[0061] 14 explicitly states that combinability is not given, or this is evident from the context.

[0062] Figure 1 shows a schematic cross-section of a pneumatic tire with a circumferential reinforcement layer arranged between two cross-belts, divided into five segments: two A segments, two B segments, and one central C segment. The circumferential reinforcement layer has a high EPDM in the A segments, a medium EPDM in the B segments, and a low EPDM in the C segment.

[0063] Figures 2A to 2D show tire cross-sections according to the prior art and different embodiments of the invention. Figure 2A shows the structure of a conventional circumferential reinforcement layer with a consistently high cord density. Figures 2B to 2D, on the other hand, show pneumatic tires according to the invention with circumferential reinforcement layers according to the concept of the invention described herein (B to D). The figures each depict the area of ​​the circumferential reinforcement layer up to the tire center, with sections A, B, and C. In Figure 2A, the cords in areas A, B, and C are arranged with the same epdm; in Figure 2B, the cords in areas B and C have an epdm of 0; in Figure 2C, the cords in area C have an epdm of 0 and in area B an epdm that is smaller than the epdm in area A; and in Figure 2D, epdm (A) > epdm (B) > epdm (C).

[0064] Figures 3A to 3D show the structure of the circumferential reinforcement layers in isolation and magnification, with Figure 3A again showing a circumferential reinforcement layer according to the prior art. The layer shown in Figure 2B has an edge region with a steel cord density of 39 epdm and a central region without steel cords. The layer shown in Figure 2C has an edge region with a steel cord density of 39 epdm, an adjacent region with a steel cord density of 15 epdm, and a central region without steel cords. The layer shown in Figure 2D corresponds to the layer shown in Figure 2C, with the exception that steel cords with a density of 9 epdm are provided in the central region. 202405654

[0065] 15

[0066] The present invention and the effects achieved therein are illustrated in more detail below by means of some exemplary embodiments, which, however, are not to be considered in any way as limiting the scope of protection of the application.

[0067] Examples

[0068] Various tire constructions with dimensions 315 / 70 R225 with a carcass layer, a belt layer arranged above it with a high belt angle (50°), a pair of cross belts (angle 18° or -18°), a circumferential reinforcement layer arranged between the cross belts and a tread rubber applied over the cross belts were simulated using software developed for this purpose.The circumferential reinforcement layer in the tires was specified in such a way that a conventional circumferential reinforcement layer with equal spacing of the steel cords over the entire width (40 EPDM = "Ends per Decimeter" corresponds to ends / 100 mm, reference), an edge area with a conventional steel cord density of 39 EPDM over a width of 43 mm and a "middle area" without steel cords (Variant 1), an edge area with a conventional steel cord density of 40 EPDM over a width of 43 mm and connected to this an area with a steel cord density of 15 EPDM over a width of 39 mm and a "middle area" without steel cords (Variant 2) and a structure as in Variant 2, in which steel cords with a density of 9 EPDM were included in the middle area (= Variant 3) was specified.The simulated tires had 5 main circumferential grooves and the steel cord plies had a width of 290 mm (high belt angle belt ply), 310 mm (first cross belt), 242 mm (circumferential reinforcement layer, reference) and 298 mm (second cross belt).

[0069] For these tires, the free longitudinal rolling forces in the region of ribs 1 to 6 (determined by 5 main circumferential grooves) of the tires were simulated at a load of 7.4 t and a pressure of 10 bar. The results of the simulations are shown in Fig. 4 and the following Table 1: 202405654

[0070] 16

[0071] Table 1:

Claims

202405654 17 Patent claims 1. Pneumatic tire comprising a carcass layer, a belt layer arranged on the outside of the carcass layer, and a tread rubber arranged on the outside in the radial layer of the belt layer, wherein the belt layer has a circumferential reinforcement layer embedded between other belt layers, having a belt angle within a range of ± 5° with respect to the tire's circumferential direction, and wherein the circumferential reinforcement layer is formed by steel cords, characterized in that the circumferential reinforcement layer has a number of ends of the belt cords constituting the circumferential reinforcement layer in the region of their edges that is at least 30% greater than the number of ends of the belt cords constituting the circumferential reinforcement layer in the central region of the circumferential reinforcement layer at the tire equator.

2. Pneumatic tire according to claim 1, wherein the number of ends of the belt cords constituting the circumferential reinforcement layer in the region of their edges is greater by at least 100%, in particular by at least 150% and more preferably by at least 200% than the number of ends of the belt cords constituting the circumferential reinforcement layer in the central region of the circumferential reinforcement layer.

3. Pneumatic tire according to claim 1 or 2, wherein the steel cords forming the circumferential reinforcement layer have a diameter that differs by no more than ± 10% from the diameter of all other steel cords in the circumferential reinforcement layer.

4. Pneumatic tire according to any one of claims 1 to 3, wherein the steel cords forming the circumferential reinforcement layer have an elongation at break of less than 4.5%, preferably less than 4.0%, and more preferably in the range of 2 to 3%. 202405654 18 5. Pneumatic tire according to at least one of the preceding claims, wherein the circumferential reinforcement layer, defined from the tire equator to the tire shoulder, has two areas with a uniform number of ends of the belt cords constituting the circumferential reinforcement layer over the respective area.

6. Pneumatic tire according to at least one of claims 1 to 4, wherein the circumferential reinforcement layer, defined from the tire equator to the tire shoulder, has three areas with a uniform number of ends of the belt cords constituting the circumferential reinforcement layer over the respective area.

7. Pneumatic tire according to at least one of the preceding claims, wherein the circumferential reinforcement layer in the area of ​​the edge has a number of the ends of the belt cords constituting the circumferential reinforcement layer which are uniform over a distance of 2 to 5 cm and preferably 3 to 5 cm.

8. Pneumatic tire according to at least one of the preceding claims, wherein the circumferential reinforcement layer in the area of ​​the edge has a number of ends of the belt cords constituting the circumferential reinforcement layer of 34 to 60 ends / 100 mm and preferably 38 to 50 ends / 100 mm.

9. Pneumatic tire according to at least one of the preceding claims, wherein the circumferential reinforcement layer at the tire equator in the region of the center has a number of ends of the belt cords constituting the circumferential reinforcement layer of 0 to 28 ends / 100 mm, preferably 5 to 25 ends / 100 mm, and more preferably 5 to 16 ends / 100 mm.

10. Pneumatic tire according to at least one of the preceding claims, wherein the circumferential reinforcement layer between the tire equator and the edge region has a further region in which the number of 202405654 19 The number of ends of the belt cords constituting the circumferential reinforcement layer differs by at least 20% from the number of ends in the area of ​​the edge and at the tire equator, wherein preferably the number of ends of the belt cords constituting the circumferential reinforcement layer in this area is 10 to 25 ends / 100 mm and more preferably 13 to 20 ends / 100 mm and / or wherein the further area has a width in the range of 10 to 25% and preferably 15 to 25% cm of the width of the circumferential reinforcement layer.

11. Pneumatic tire according to at least one of the preceding claims, wherein the pneumatic tire has a pair of cross belts having a belt angle, as an absolute value, of not less than 10° and not more than 45° with respect to the tire circumferential direction with opposite signs, wherein preferably the circumferential reinforcement layer is arranged in the tire radial direction between the first and second cross belts.

12. Pneumatic tire according to at least one of the preceding claims, wherein the pneumatic tire further comprises a belt with a belt angle, as an absolute value, of not less than 45° and not more than 70°, which is preferably laminated on the outside in the tire radial direction of the carcass layer.

13. Pneumatic tire according to at least one of the preceding claims, having an aspect ratio of 80% or less, preferably 70% or less and more preferably 60% or less.

14. Pneumatic tire according to at least one of the preceding claims, wherein the pneumatic tire has at least two further belt layers in addition to the circumferential reinforcement layer and the width of the circumferential reinforcement layer is less than the width of at least two belt layers of the further belt layers, wherein preferably the two belt layers extend further in both lateral directions relative to the tire equator than the circumferential reinforcement layer. 202405654 20 15. Pneumatic tire according to at least one of the preceding claims, wherein the edge region of the circumferential reinforcement layer extends over the main circumferential grooves of the tire which are furthest from the tire equator, wherein preferably the point at which the edge region ends is spaced not less than 2 mm, preferably not less than 3 mm from the edge of the main circumferential groove, when the distance is determined on the tread surface of the tire.

16. Method for manufacturing a belt package with multiple belt layers, one of which is a belt layer consisting of steel cords embedded in a rubber layer, wherein the steel cords are coated with rubber in a first step and are wound onto a lower belt layer at an angle of ± 5° with respect to the tire's circumferential direction in a second step to form a belt layer, wherein the steel cords are applied to the lower belt layer by means of a spooling head, the spooling head being operated with a different feed rate for the steel cord such that in outer areas of the belt layer, steel cords with a smaller distance between two steel cords are applied to the belt layer than in the area located in the middle of the belt layer, and wherein the combination of belt layers thus generated is combined with at least one further belt layer to form a belt package.

17. A method for manufacturing a pneumatic tire comprising providing a carcass package, applying a belt package comprising a belt layer manufactured according to the method of claim 16, and a tread layer, wherein the carcass package is provided as the bottom layer, the belt package is applied to this layer, and the tread is applied thereto, and wherein in a final step the pneumatic tire is formed in a mold by vulcanizing the composite of carcass package, belt package and tread layer. 202405654 21 18. Use of a circumferential reinforcement layer with a non-uniform spacing of the ends of the belt cords constituting the circumferential reinforcement layer in a pneumatic tire to optimize the tire contact patch and / or the tire abrasion profile, wherein the circumferential reinforcement layer has a belt angle within a range of ± 5° with respect to the tire circumferential direction, and wherein the number of ends of the steel cords forming the circumferential reinforcement layer is greater in the edge region, preferably by at least 30% greater, than in the central region of this layer.

19. Vehicle, in particular in the form of a truck or bus, equipped with at least one pneumatic tire according to any one of claims 1 to 14.

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