PNEUMATIC VEHICLE TIRES

Description

[0001] The invention relates to a vehicle pneumatic tire with a directional tread having two shoulder-side profile ribs, two middle profile ribs, and a central profile rib, wherein the profile ribs are separated by two shoulder-side circumferential grooves and two middle circumferential grooves, wherein the shoulder-side profile ribs and the middle profile ribs are divided into profile blocks by transverse grooves extending in a V-shape across the tread width and parallel to each other within the profile ribs, which open into the shoulder-side circumferential grooves, and wherein the shoulder-side circumferential grooves have groove sections that, in a top view, extend inclined to the circumferential direction, each separating a profile block of the middle profile ribs from a profile block of the shoulder-side profile ribs, with an incoming end and a trailing end that first enters the ground when the tire rolls during forward travel, wherein the transverse grooves,which run in the central profile ribs, end at an axially determined distance in front of the respective central circumferential groove, wherein the groove sections of the shoulder-side circumferential grooves, viewed from above, are inclined to the circumferential direction such that the incoming ends of the groove sections are closer to the tire equatorial plane than the outgoing ends of the groove sections.

[0002] Such a vehicle pneumatic tire is known, for example, from EP 3 702 176 A1. The tire has a tread with five profile ribs separated by circumferential grooves, the shoulder-side circumferential grooves having groove sections running at an angle of 5° to 15° to the circumferential direction. The shoulder-side profile ribs and the central profile ribs are divided into profile blocks by transverse grooves extending in a V-shape across the tread width in plan view and merging into the shoulder-side circumferential grooves. The transverse grooves running in the central profile ribs terminate at an axially determined distance in front of the respective central circumferential groove. The central profile ribs therefore each have a band-shaped rib section on the inside of the tread and a rib section on the outside of the tread, which is divided into the profile blocks by the transverse grooves.The vehicle's pneumatic tire should exhibit good wet performance and a good response to steering forces.

[0003] From DE 10 2012 104 719 A1, a pneumatic tire with a directional tread pattern and five profile ribs is known, wherein the shoulder-side profile ribs and the middle profile ribs are divided into profile blocks by transverse grooves extending in a V-shape across the width of the tread when viewed from above. The circumferential grooves on the shoulders have groove sections inclined to the circumferential direction when viewed from above. In the profile blocks of the middle profile ribs, a transverse groove is formed, extending from the adjacent shoulder-side profile rib and ending in a snare-like groove within the respective profile block. The tire is intended to exhibit good wet and snow braking performance.

[0004] US Patent 2010 / 116392 A1 discloses a pneumatic tire with a tread featuring five profile ribs separated by circumferential grooves. The shoulder ribs have tread blocks, and the central rib is band-shaped. Each of the central ribs has a narrow circumferential groove and alternating transverse grooves running through the central rib and between the adjacent shoulder circumferential groove and the narrow circumferential groove. This tread pattern results in each central rib having longer, circumferentially oriented tread blocks located on the inner side of the tread and two shorter, circumferentially oriented tread blocks located on the outer side of the tread, each associated with a longer, circumferentially oriented tread block. The tire is designed to offer good performance in icy and wet conditions.

[0005] From DE 10 2010 006 051 A1, another pneumatic tire is known with a tread featuring five profile ribs separated by circumferential grooves. The central profile ribs have alternating transverse grooves running circumferentially, ending in a sac-like groove. The central profile rib is laterally provided with circumferentially elongated projections, each with a surface that slopes radially inwards towards the outer edge of the tread. The tire is designed to offer good performance in both snow and dry conditions.

[0006] Furthermore, JP 2015 171 872 A discloses a pneumatic tire for vehicles with a tread featuring five profile ribs, wherein the central profile ribs have lateral grooves that terminate in a sack-like manner and have an L-shape when viewed from above. The pneumatic tire is said to exhibit good wet performance and good responsiveness to steering forces.

[0007] A vehicle tire, which is a winter tire with spikes in the tread, is known, for example, from DE 10 2015 221 118 A1. The tire has a tread with a central profile rib, two intermediate profile ribs, and two shoulder-side profile ribs. The central profile rib is traversed by transverse grooves that run parallel to each other when viewed from above. The transverse grooves formed in the shoulder-side and intermediate profile ribs are arc-shaped when viewed from above. The shoulder-side circumferential grooves have groove sections that are inclined in the circumferential direction when viewed from above, and simultaneously inclined in the opposite direction to the transverse grooves with respect to the circumferential direction. These groove sections separate a profile block of the respective intermediate profile rib from a profile block of the adjacent shoulder-side profile rib.Spikes are anchored in the profile blocks of the middle profile ribs and the profile blocks of the shoulder-side profile ribs, which are surrounded by depressions formed in the profile blocks that act as ice reservoirs.

[0008] The type of pneumatic tires mentioned above are primarily used as winter tires. The V-shaped lateral grooves running across the width of the tread enable, on the one hand, high water displacement towards the tread shoulder (good wet performance) and, on the other hand, a certain amount of snow accumulation when driving on snow. This snow-on-snow friction effect provides advantages in terms of snow performance. Since winter tires are also frequently used on dry roads, their dry performance is not to be overlooked.

[0009] The invention is based on the objective of improving the dry, wet and snow performance of a vehicle pneumatic tire of the type mentioned above as equally as possible.

[0010] The problem set out in the invention is solved by the fact that the transverse grooves have a width of 3.5 mm to 6.5 mm, wherein connecting grooves run between the inner ends of the transverse grooves, which run in the middle profile ribs, and the middle circumferential grooves, which are narrower and shallower than the transverse grooves running in the middle profile ribs.

[0011] The inclined groove sections of the shoulder-side circumferential grooves, in combination with the lateral grooves, ensure effective drainage of the tread pattern when driving on wet roads, particularly improved water displacement from the contact patch, and thus enhanced wet performance. The central tread ribs are stiffened by the "bag-shaped" lateral grooves that terminate before the respective central circumferential groove, thereby improving power transmission from the tire to the road surface and thus improving dry performance. Additionally, snow accumulates well in the bag-shaped lateral grooves when driving on snow-covered roads and is effectively compacted, thereby increasing the effect of snow-on-snow friction and thus achieving advantages in terms of snow performance.

[0012] The connecting grooves "decouple" the profile blocks of the central profile ribs from each other to a certain degree, which contributes to the occurrence of a uniform wear pattern of the tread and thus to maintaining good dry performance.

[0013] According to a preferred embodiment, the distance at which the transverse grooves running in the central profile ribs terminate in front of the respective central circumferential groove is 3.0 mm to 15.0 mm, in particular 5.0 mm to 10.0 mm. This design of the sack-shaped transverse grooves is particularly advantageous with regard to dry performance.

[0014] Furthermore, it is advantageous if the groove sections of the shoulder-side circumferential grooves, viewed from above, run at an angle of 2° to 7° to the circumferential direction, particularly at a maximum of 5°. Such inclined groove sections promote water drainage towards the lateral edges of the soil contact area, while simultaneously maintaining a high water drainage capacity in the circumferential direction within the shoulder-side circumferential grooves. This further improves wet-weather performance.

[0015] Another preferred embodiment is characterized in that the connecting grooves have a depth of 2.0 mm to 5.0 mm and a width of 1.5 mm to 3.5 mm. The preferred, correspondingly shallow design of the connecting grooves promotes snow accumulation in the transverse grooves when driving on snow.

[0016] Preferably, the connecting grooves, viewed from above, run in the axial direction or at an angle of up to 5° to it.

[0017] According to a further preferred embodiment, the central profile rib is traversed by transverse grooves running parallel to each other in plan view. Each of these grooves is composed of two V-shaped groove sections running at an angle of at most 12° to each other and to the axial direction. The inclination of the groove sections with respect to the axial direction is the same as the inclination of the transverse grooves running in the nearest central profile rib. The transverse grooves in the central profile rib have a width of preferably 1.8 mm to 3.5 mm and a maximum depth of preferably 70% to 100%, particularly 100%, of the profile depth. The selected V-shape of the transverse grooves contributes to the drainage of the central profile rib and therefore to the improvement of wet performance. If the transverse grooves are designed according to the preferred depth and width, the central profile rib exhibits a stiffness that is advantageously high for dry performance.

[0018] According to a further preferred embodiment of the invention, the central profile rib, the middle profile ribs, and the shoulder-side profile ribs each have a maximum width determined axially at the tread periphery, wherein the maximum width of the middle profile ribs is greater than the maximum width of the central profile rib, and wherein the maximum width of the shoulder-side profile rib is determined within the ground contact area and is greater than the maximum width of the middle profile ribs. The lateral stiffness of the profile ribs thus increases from profile rib to profile rib towards the tread shoulder. This is particularly advantageous for dry performance when cornering.

[0019] In this context, it is advantageous if the maximum width of the central profile rib is 13.5% to 14.7% of the axially determined width of the ground contact area of ​​the tread.

[0020] Furthermore, in this context it is advantageous if the maximum width of the central profile ribs is 15.8% to 17.3% of the axially determined width of the ground contact area of ​​the tread, and preferably 108% to 123%, in particular 110% to 120%, of the width of the central profile rib.

[0021] Furthermore, in this context it is advantageous if the maximum width of the shoulder-side profile ribs is 19.0% to 21.0% of the axially determined width of the ground contact area of ​​the tread and preferably 117% to 127% of the width of the middle profile ribs.

[0022] According to a further preferred embodiment, the profile blocks belonging to the central profile ribs and the shoulder-side profile ribs are each traversed by a number of incisions running parallel to the transverse grooves in plan view, with a width of 0.4 mm to 1.0 mm and a maximum depth of 75% to 100% of the profile depth. Due to their parallel orientation to the transverse grooves, the incisions—compared, for example, to incisions running at an angle to the transverse grooves in plan view—have a length that facilitates good opening of the incisions, so that the incisions collect more snow when driving on snow and thus contribute to a further improvement in snow performance.

[0023] Another preferred embodiment is characterized in that the profile blocks belonging to the middle profile ribs and the shoulder-side profile ribs are each provided with a number of microgrooves, which run at an angle of up to 10° in plan view to the circumferential direction, and in particular run perpendicular to the transverse grooves, with a width and depth of 0.3 mm to 0.6 mm.

[0024] Another preferred embodiment is characterized in that the central profile rib is provided with a number of microgrooves extending circumferentially in plan view, each with a width and depth of 0.3 mm to 0.6 mm.

[0025] These micro-grooves help to improve the grip characteristics of new or lightly worn tires.

[0026] Other preferred designs relate to the orientation of the transverse grooves, with these designs primarily contributing to an improvement in wet performance.

[0027] The transverse grooves, which divide the central profile ribs into profile blocks, run, viewed from above, preferably at an angle of 30° to 45° to the axial direction.

[0028] The transverse grooves, which divide the shoulder-side profile ribs into profile blocks, run, viewed from above, preferably at an angle of 0° to 25° to the axial direction, in particular from 5° to 20°.

[0029] Further features, advantages and details of the invention will now be explained with reference to the single figure, Fig. 1 , which schematically shows a top view of a circumferential section of a tread of a vehicle pneumatic tire with an embodiment of the invention, is described in more detail.

[0030] Vehicle pneumatic tires designed according to the invention are tires for motor vehicles, in particular for multi-track motor vehicles, and preferably radial tires for passenger cars, vans or light trucks, wherein the tires are intended for use under winter driving conditions.

[0031] Fig. 1 Figure 1 shows a top view of a circumferential section of a tread of a vehicle tire. The tire equatorial plane is indicated by a dashed line AA, and the lateral edges of the tread's contact patch are indicated by dashed lines l. The contact patch corresponds to the statically determined footprint according to ETRTO standards (load at 70% of the maximum load capacity at an internal pressure of 85% according to the ETRTO standard) and has a width B in the axial direction.

[0032] The tread is noise-optimized in a particularly known manner using a pitch length variation method and features a directional tread pattern, wherein the tire is to be mounted on the vehicle such that it exhibits the rolling direction indicated by the arrow R when driving forward. Furthermore, the tread has a central profile rib 1, two adjacent central profile ribs 2, and two shoulder-side profile ribs 3, and in the illustrated embodiment is symmetrical with respect to the tire equatorial plane (line AA).

[0033] The central profile ribs 2 are each separated from the central profile rib 1 by a central circumferential groove 4, which, for example, appears straight in plan view, and from the adjacent shoulder-side profile rib 3 by a shoulder-side circumferential groove 5, which, in plan view, appears sawtooth-shaped. The circumferential grooves 4, 5 are designed to the respective intended tread depth, which for the preferred tire type is typically 6.5 mm to 10.0 mm, and have a width b UR of 6.0 mm to 13.0 mm, determined perpendicular to their direction of extension.

[0034] The central profile rib 1 has a maximum width b 1 of 13.5% to 14.7% of the width B of the ground contact area at the periphery of the tread in the axial direction, which is constant in the illustrated embodiment. It is provided around its circumference with a plurality of incision-like transverse grooves 6 that run parallel to each other in plan view and open into the central circumferential grooves 4. These transverse grooves run axially in plan view with respect to a line connecting the ends of the transverse grooves, have a width of 1.8 mm to 3.5 mm perpendicular to their extent, and a maximum depth of 70% to 100%, preferably 100%, of the profile depth in the radial direction.In the illustrated embodiment, the transverse grooves 6, viewed from above, consist of two shallow V-shaped groove sections 6a, each extending straight and at an angle α of at most 12° to the axial direction. The ends of these sections, located at the tire's equatorial plane (line AA), are the first to engage the ground when the tire rolls forward (arrow R). Furthermore, the central profile rib 1 is traversed by narrower incisions 7, which run parallel to the transverse grooves 6 in a top view. In the areas between the incisions 7, and in the areas between the edge incisions 7 and the transverse grooves 6, two circumferentially extending micro-grooves 12 are formed – one micro-groove 12 on each side of the tire's equatorial plane – which preferably open into a incision 7 or into a transverse groove 6.

[0035] Each central profile rib 2 is provided with central transverse grooves 8 running parallel to each other in plan view, and each shoulder-side profile rib 3 is provided with shoulder-side transverse grooves 9 running parallel to each other in plan view, wherein the transverse grooves 8, 9 extend in a V-shape across the tread width and therefore continue at least substantially in each half of the tread, and wherein the central transverse grooves 8 enter the substrate first with their ends on the inside of the tread. The transverse grooves 8, 9 each have a maximum radial depth of 70% to 100% of the profile depth and, at the tread periphery, a width bQR of 3.5 mm to 6.5 mm, determined perpendicular to their groove centerline mQR, which follows the groove path in plan view.

[0036] Each central profile rib 2 has a maximum width b 2 of 15.8% to 17.3% of the width B of the ground contact area at the tread periphery in the axial direction, wherein the maximum width b 2 is preferably 108% to 123%, in particular 110% to 120%, of the maximum width b 1 of the central profile rib 1.The transverse grooves 8 open into the shoulder-side circumferential grooves 5, terminate within the central profile rib 2 at a distance a 1 of 3.0 mm to 15.0 mm, in particular 5.0 mm to 10.0 mm, determined at the tread periphery and in the axial direction, in front of the respective central circumferential groove 4, run in a slightly arcuate shape in plan view and - with respect to the groove centerlines m QR - at an angle β of 30° to 45° to the axial direction, the angle β decreasing continuously by in particular up to 5° over the extension of the transverse grooves 8 towards the tread shoulder, and divide the central profile rib 2 in plan view into essentially parallelogram-shaped central profile blocks 2a.Between the inner end of each transverse groove 8 and the nearest central circumferential groove 4, a short connecting groove 15 extends axially in plan view. This groove is narrower and shallower than the transverse groove 8 and has a width of preferably 1.5 mm to 3.5 mm and a radial depth of preferably 2.0 mm to 5.0 mm. The central profile blocks 2a are each provided with a number of incisions 10, which, in plan view, run parallel to the groove centerlines m QR of the central transverse grooves 8, have an axially extending edge section 10a that opens into the corresponding central circumferential groove 4, and traverse the central profile blocks 2a.In the areas between the incisions 10 and in the areas between the edge incisions 10 and the transverse grooves 6, at least two microgrooves 13 are formed in top view to the circumferential direction at an angle of in particular up to 10°, which preferably open into a incision 10 or into a transverse groove 8.

[0037] Each shoulder-side profile rib 3 has a maximum width b 3 of 19.0% to 21.0% of the width B of the ground contact area in the axial direction at the tread periphery, determined within the ground contact area, wherein the maximum width b 3 is preferably 117% to 127% of the maximum width b 2 of the middle profile rib 2. The shoulder-side transverse grooves 9 merge into the shoulder-side circumferential grooves 5, extend beyond the respective lateral edge of the ground contact surface (line l) and, in plan view, are slightly curved and – with respect to the groove centerlines m QR – to the axial direction at an angle γ of 0° to 25°, in particular of 5° to 20°, whereby the angle γ within the ground contact surface decreases continuously by, in particular, up to 15° over the extension of the transverse grooves 9 towards the tread shoulder and divide the shoulder-side profile block rows 3 into shoulder-side profile blocks 3a.The shoulder-side profile blocks 3a are each provided with a number of incisions 11 which, in plan view, extend parallel to the groove centerlines m QR of the transverse grooves 9 and traverse the profile blocks 3a at least within the ground contact area. In the areas between the incisions 11 and in the areas between the edge-side incisions 11 and the shoulder-side transverse grooves 9, in particular four micro-grooves 14 are formed within the ground contact area, extending in plan view to the circumferential direction at an angle of up to 10°, in the exemplary embodiment perpendicular to the groove centerlines m QR of the shoulder-side transverse grooves 9, which preferably open into a incision 11 or into a transverse groove 9.

[0038] The maximum widths b1, b2 of the profile ribs 1, 2 mentioned above were determined at the periphery of the tread between the points of the respective profile ribs 1, 2 that are furthest apart in the axial direction. The maximum width b3 of the shoulder-side profile ribs 3 mentioned above was determined between the respective lateral edge of the ground contact area (line l) and the point of profile rib 3 furthest from this edge in the axial direction at the periphery of the tread. The correspondingly varying angles β and γ of the transverse grooves 8, 9 mentioned above were each determined relative to a tangent applied locally to the centerline m QR. All incisions 7 (central profile rib 1), 10 (middle profile blocks 2a), 11 (shoulder-side profile blocks 3a) have a width of 0.4 mm to 1.0 mm, in particular of a maximum of 0.8 mm, and in the radial direction a maximum depth of 75% to 100%, in particular of 80% to 95%, of the profile depth.All microgrooves 12 (central profile rib 1), 13 (middle profile blocks 2a), 14 (shoulder-side profile blocks 3a) have a width and depth of 0.3 mm to 0.6 mm, wherein the width is preferably 0.4 mm and the depth is preferably 0.5 mm.

[0039] Due to the V-shaped orientation of the transverse grooves 8, 9, each shoulder-side circumferential groove 5 has a plurality of groove sections 5a, each separating a shoulder-side profile block 3a from the adjacent central profile block 2a and therefore extending to the transverse grooves 8, 9. Viewed from above, the groove sections 5a run straight and at an angle δ of 2° to 7°, and in particular at most 5°, to the circumferential direction, with all groove sections 5a of a shoulder-side circumferential groove 5 running parallel to each other in plan view. Each groove section 5a has an incoming end 5a' and a trailing end 5a'' that first enters the surface when the tire rolls forward, and is inclined relative to the circumferential direction such that the incoming end 5a' is closer to the tire's equatorial plane (line AA) than the trailing end 5a''.The width b UR of the shoulder-side circumferential grooves 5 and the angle δ of the groove sections 5a are preferably matched such that the shoulder-side circumferential grooves 5 have no or a reduced "lookthrough", i.e., that, viewed in the axially oriented cross-section, no or a reduced view through the shoulder-side circumferential grooves 5 is possible.

[0040] The invention is not limited to the described embodiment. In particular, the maximum widths b1, b2, b3 of the tread ribs 1, 2, 3 may differ from the dimensions mentioned. Furthermore, the incisions 7, 10, 11 and the microgrooves 12, 13, 14 are optional. Additionally, the transverse grooves 6 in the central tread rib 1 may be of a conventional design, and the transverse grooves 8, 9 in the tread ribs 2, 3 may also be straight in plan view. The central tread rib 2 and the shoulder-side tread rib 3, located in one half of the tread, may have circumferentially offset tread blocks 2a, 3a and transverse grooves 8, 9 relative to the central tread rib 2 and the shoulder-side tread rib 3, located in the other half of the tread, so that the tread is not symmetrical with respect to the tire equatorial plane (line AA). Reference number list

[0041] 1 Central profile rib 2 Middle profile rib 2a Middle profile block 3 Shoulder-side profile rib 3a Shoulder-side profile block 4 Middle circumferential groove 5 Shoulder-side circumferential groove 5a Groove section 5a Leading end 5a Trailing end 6 Cut-like transverse groove 6a Groove section 7 Cut 8 Middle transverse groove 9 Shoulder-side transverse groove 10 Cut 10a Cut section 11 Cut 12, 13, 14 Microgroove 15 Connecting groove a 1 Distance A-A Line (tire equatorial plane) B Width b 1 , b 2 , b 3 Maximum width b QR , b UR Width 1 Line (lateral edge of the ground contact area) m QR Groove center line RP Arrow (direction of rolling) α, β, γ, δ Angle

Claims

1. Pneumatic vehicle tyre with a directional tread strip with two shoulder-side profile ribs (3), two middle profile ribs (2) and one central profile rib (1), the profile ribs (1, 2, 3) being separated by two shoulder-side circumferential grooves (5) and two middle circumferential grooves (4), the shoulder-side profile ribs (3) and the middle profile ribs (2) being divided into profile blocks (2a, 3a) by way of transverse grooves (8, 9) which run in a V-shaped manner in plan view across the width of the tread strip, run parallel to one another within the profile ribs (2, 3) and open into the shoulder-side circumferential grooves (5), and the shoulder-side circumferential grooves (5) having groove sections (5a) which run inclined to the circumferential direction in plan view, each separate a profile block (2a) of the middle profile ribs (2) from a profile block (3a) of the shoulder-side profile ribs (3), and have a leading end (5a'), encountering the underlying surface first when the tyre rolls during forward travel, and a trailing end (5a"), the transverse grooves (8) which run in the middle profile ribs (2) ending in front of the respective middle circumferential groove (4) at a spacing (a1) determined in the axial direction, the groove sections (5a) of the shoulder-side circumferential grooves (5), seen in plan view, being inclined to the circumferential direction in such a way that the leading ends (5a') of the groove sections (5a) are closer to the tyre equatorial plane (line A-A) in comparison with the trailing ends (5a") of the groove sections (5a), characterized in that the transverse grooves (8, 9) have a width (bqR) of 3.5 mm to 6.5 mm, connecting grooves (15) running between the ends on the inside of the tread strip of the transverse grooves (8) which run in the middle profile ribs (2) and the middle circumferential grooves (4), which connecting grooves are of narrower and shallower design than the transverse grooves (8) running in the middle profile ribs (2).

2. Pneumatic vehicle tyre according to Claim 1, characterized in that the spacing (a1) at which the transverse grooves (8) running in the middle profile ribs (2) end in front of the respective middle circumferential groove (4) is from 3.0 mm to 15.0 mm, in particular 5.0 mm to 10.0 mm.

3. Pneumatic vehicle tyre according to Claim 1 or 2, characterized in that the groove sections (5a) of the shoulder-side circumferential grooves (5), in plan view, run at an angle (δ) of 2° to 7°, in particular of at most 5°, with respect to the circumferential direction.

4. Pneumatic vehicle tyre according to one of Claims 1 to 3, characterized in that the connecting grooves (15) have a depth of 2.0 mm to 5.0 mm and a width of 1.5 mm to 3.5 mm.

5. Pneumatic vehicle tyre according to one of Claims 1 to 4, characterized in that the connecting grooves (15), in plan view, run in the axial direction or at an angle of up to 5° with respect thereto.

6. Pneumatic vehicle tyre according to one of Claims 1 to 5, characterized in that the central profile rib (1) is traversed by transverse grooves (6) which run parallel to one another in plan view and which each consist of two groove sections (6a) which run toward one another in a V-shaped manner and at an angle (α) of at most 12° with respect to the axial direction, the inclination of the groove sections (6a) with respect to the axial direction being in the same direction as the inclination of the transverse grooves (8) running in the respective middle profile rib (2) that is nearest, and the transverse grooves (6) in the central profile rib (1) having a width of preferably 1.8 mm to 3.5 mm and a maximum depth of preferably 70% to 100%, in particular 100%, of the profile depth.

7. Pneumatic vehicle tyre according to one of Claims 1 to 6, characterized in that the central profile rib (1), the middle profile ribs (2) and the shoulder-side profile ribs (3) each have a maximum width (b1, b2, b3) which is determined in the axial direction on the tread strip periphery, the maximum width (b2) of the middle profile ribs (2) being greater than the maximum width (b1) of the central profile rib (1), and the maximum width (b3) of the shoulder-side profile rib (3) being determined within the ground contact area and being greater than the maximum width (b2) of the middle profile ribs (2).

8. Pneumatic vehicle tyre according to Claim 7, characterized in that the maximum width (b1) of the central profile rib (1) is 13.5% to 14.7% of the width (B), determined in the axial direction, of the ground contact area of the tread strip (1).

9. Pneumatic vehicle tyre according to Claim 7 or 8, characterized in that the maximum width (b2) of the middle profile ribs (2) is 15.8% to 17.3% of the width (B), determined in the axial direction, of the ground contact area of the tread strip, and preferably 108% to 123%, in particular 110% to 120%, of the width (b1) of the central profile rib (1).

10. Pneumatic vehicle tyre according to one of Claims 7 to 9, characterized in that the maximum width (b3) of the shoulder-side profile ribs (2) is 19.0% to 21.0% of the width (B), determined in the axial direction, of the ground contact area of the tread strip, and preferably 117% to 127% of the width (b2) of the middle profile ribs (2).

11. Pneumatic vehicle tyre according to one of Claims 1 to 10, characterized in that the profile blocks (2a, 3a) belonging to the middle profile ribs (2) and to the shoulder-side profile ribs (3) are in each case traversed by a number of sipes (10, 11) running parallel to the transverse grooves (8, 9) in plan view with a width of 0.4 mm to 1.0 mm and a maximum depth of 75% to 100% of the profile depth.

12. Pneumatic vehicle tyre according to one of Claims 1 to 11, characterized in that the profile blocks (2a, 3a) belonging to the middle profile ribs (2) and to the shoulder-side profile ribs (3) are in each case provided with a number of microgrooves (13, 14) running, in plan view, at angle of up to 10° with respect to the circumferential direction, in particular perpendicular to the transverse grooves (8, 9), with a width and a depth of 0.3 mm to 0.6 mm in each case.

13. Pneumatic vehicle tyre according to one of Claims 1 to 12, characterized in that the central profile rib (1) is provided with a number of microgrooves (12) running in the circumferential direction in plan view and having a width and a depth of 0.3 mm to 0.6 mm each.

14. Pneumatic vehicle tyre according to one of Claims 1 to 13, characterized in that the transverse grooves (8) which divide the middle profile ribs (2) into profile blocks (2a), viewed in plan view, run at an angle (β) of 30° to 45° with respect to the axial direction.

15. Pneumatic vehicle tyre according to one of Claims 1 to 14, characterized in that the transverse grooves (9) which divide the shoulder-side profile ribs (3) into profile blocks (3a), viewed in plan view, run at an angle (γ) of 0° to 25°, in particular of 5° to 20° with respect to the axial direction.