VEHICLE AIR TIRES

Description

[0001] The invention relates to a vehicle pneumatic tire with a tread having at least one shoulder-side profile rib bounded by a circumferential groove, the outer surface of which has a rib in the tread periphery, and an inner rib section extending within the ground contact area and an outer rib section extending outside the ground contact area, wherein transverse grooves extending in both the inner and outer rib sections and terminating in front of the circumferential groove with a maximum circumferential width of 3.0 mm to 8.0 mm are formed in the shoulder-side profile rib, wherein each transverse groove has two groove edges located on the outer surface of the rib and is bounded by a groove base and two groove walls extending from each of the groove edges, wherein the groove walls each have a single inclined surface extending from the groove edge in the direction of extension of the transverse groove.

[0002] Such a pneumatic tire is known, for example, from DE 10 2019 206 654 A1. The tire has a tread with transverse grooves with a maximum width of 5.0 mm to 7.0 mm, two groove edges, and two groove walls, each with a chamfer (inclined surface) extending from the corresponding groove edge and forming a triangular chamfer run-off. The triangular chamfer run-off of the first chamfer is bounded by a chamfer edge, and the second chamfer is bounded by a second chamfer edge. The chamfer edge of the second chamfer contacts a support surface extending from the chamfer edge of the first chamfer with an end chamfer edge segment. Due to such "nested" chamfers, the chamfer edges shorten only slowly as the tread wears down, and the chamfers and chamfer edges no longer disappear abruptly, thus maintaining good braking properties on dry roads even with further advanced tread wear.

[0003] From DE 10 2016 219 017 A1, a vehicle pneumatic tire is known with a tread having a shoulder-side profile rib with four rows of transverse grooves, each consisting of successive transverse grooves in the circumferential direction. The transverse grooves belonging to two rows of transverse grooves each run in the inner and outer sections of the rib, end before the circumferential groove that delimits the shoulder-side profile rib, have a maximum width of 2.5 mm to 3.5 mm perpendicular to their groove centerline, and, viewed from above, each consists of an inner tread groove section and an outer tread groove section, the groove sections forming an obtuse angle with respect to the groove centerline.The transverse grooves each have two groove edges, consisting of an edge section located on the inner side of the tread and an edge section located on the outer side. Each groove is bounded by a groove base and two groove walls. Each groove wall has a single inclined surface, with one inclined surface originating from the edge section of one groove edge located on the inner side of the tread and the other inclined surface from the edge section of the other groove edge located on the outer side of the tread. The angled profile of the transverse groove, created by the groove sections, ensures a balanced overall stiffness of the tread rib, resulting in uniform wear and good braking and handling characteristics. The chamfers are beneficial for braking and handling on dry roads.With regard to wet grip, the inclination of the groove sections to the axial direction is of particular importance.

[0004] EP 3 388 256 A1 discloses a vehicle tire with a shoulder-side profile rib and transverse grooves extending in both the inner and outer sections of the rib, terminating before the circumferential groove that delimits the shoulder-side profile rib. Each transverse groove has a main section extending within the inner section of the rib, with at least one groove wall having an inclined surface extending towards the groove edge. In the outer section of the rib, the transverse groove extends as a flat depression with a continuous decrease in depth, the depression being wider than the main section. The inclined surface has a flat end section bounded by an edge section of the groove edge, the edge section having at least one kink that widens the transverse groove, and the flat end section extending along the flat depression.The transverse grooves reduce the risk of aquaplaning when cornering.

[0005] It is common practice to provide shoulder-side tread ribs with transverse grooves to facilitate drainage. Shoulder-side tread ribs with transverse grooves terminating within the rib itself exhibit higher lateral and circumferential stiffness compared to ribs with transverse grooves merging into the adjacent circumferential grooves, particularly in the critical rib section immediately adjacent to the circumferential grooves. This improves force transmission to the road surface, which is beneficial for the tire's dry performance. In the tire known from DE 10 2019 206 654 A1, the rib section adjacent to the circumferential groove is already advantageously designed in this respect due to its interlocking chamfers; however, further improvement in wet performance is desirable.

[0006] The invention is therefore based on the objective of further improving the wet performance of a vehicle pneumatic tire of the type mentioned above while maintaining good dry performance.

[0007] The problem stated in the invention is solved by forming two projections in each transverse groove within the inner section of the rib, each projection being bounded by sections of the groove walls, wherein these sections are each one of the inclined surfaces, each a projection flank and each an end surface, wherein the inclined surface bounds the respective projection in the radial direction and the end surface bounds the respective projection at its end on the outside of the tread, wherein the inclined surfaces terminate at wall sections of the groove walls converging at the end of the transverse groove on the inside of the tread, and wherein a groove narrowing of the transverse groove remains between the projections, extending beyond the projections on the inside of the tread and bounded by the converging wall sections, to which each projection is bounded by the projection flank.

[0008] The protrusions with the inclined surfaces stabilize the transverse groove and thus the profile rib, thereby ensuring the maintenance of dry performance.

[0009] Since the projections and thus the inclined surfaces are located within the inner section of the rib (i.e., within the contact patch), and the groove walls of the transverse grooves each have a single inclined surface (a characteristic of a tire of the type mentioned above), the groove walls in the area of ​​the outer section of the rib are consequently free of inclined surfaces. In the outer section of the rib, sharp groove edges are thus formed on both groove walls of the transverse groove. When driving on wet roads with sufficient amounts of water, these edges come into contact with the road surface and act as "wet grip edges." Compared to the nested chamfers (inclined surfaces) known from DE 10 2019 206 654 A1, the narrowing of the grooves improves the drainage of the tread rib, particularly in the area of ​​the inclined surfaces, and enables more efficient and low-turbulence water displacement beyond the lateral edge of the contact patch.The aforementioned wet grip edges and the narrowing of the grooves thus improve wet performance.

[0010] According to a preferred embodiment, the projecting flanks connect to the inclined surfaces via projecting edges, wherein the groove narrowing, viewed in the circumferentially oriented cross-section, has a width of 30% to 75%, particularly 40% to 70%, of the maximum width of the transverse groove, determined between lines running radially through the projecting edges. Such a wide groove narrowing is advantageous for water drainage over the lateral edge of the ground contact area and therefore for wet-weather performance.

[0011] According to a first variant of the latter preferred design, which is particularly advantageous for wet performance, the width of the groove narrowing is 1.5 mm to 3.5 mm.

[0012] According to a further advantageous embodiment, the projecting flanks, viewed in a top view and oriented circumferentially in cross-section, extend at an angle of 0° to 8°, and in particular 2° to 6°, to the radial direction. Projections with such projecting flanks are advantageous for wet performance because the groove constriction running between them has a large cross-sectional area.

[0013] According to another embodiment, the protruding edge extends at a radial depth that increases continuously towards the inside of the tread, with the depth at the inner end of the protruding edge having a first value of preferably 1.4 mm to 4.0 mm, particularly preferably up to 3.0 mm, and at the outer end of the protruding edge having a second value of preferably 40% to 65%, particularly preferably 50% to 60%, of the first value. The technical effect of this embodiment will be discussed below.

[0014] According to a fourth variant, the inclined surfaces, viewed in the circumferential cross-section in plan view, have a width along the extension of the protruding edge that increases continuously towards the inside of the tread.

[0015] The third and fourth variants are thus characterized by an increasing depth and width of the inclined surface towards the inside of the tread. These variants are advantageous for maintaining good dry performance because, under traction and braking loads, the sections of the inclined surface located further inwards on the tread are subjected to greater stress. The decreasing depth and width towards the outside of the tread somewhat compensates for the decreasing depth of the transverse groove in this direction, which contributes to maintaining good wet performance. The third and fourth variants ensure a particularly favorable compromise between good wet and good dry performance.

[0016] According to another preferred embodiment, the converging wall sections of the groove walls connect to a base section of the groove base, which, viewed in longitudinal section through the transverse groove, terminates at its inner end on the tread side in a radial direction at a depth of 1.0 mm to 3.0 mm. This base section results in a shallow design of the transverse groove at its inner end on the tread side, contributing to high transverse and circumferential stiffness in the profile rib section immediately adjacent to the circumferential groove, thereby improving force transmission to the substrate. This design therefore contributes to maintaining good dry performance.

[0017] An advantageous variant of the latter preferred embodiment consists in the fact that the base section, to which the converging wall sections connect, runs at a constant angle of 50° to 75°, particularly 60° to 70°, to the radial direction when viewed in longitudinal section through the transverse groove. This inclined base section promotes water drainage towards the outer edge of the tread and thus contributes to a further improvement in wet performance.

[0018] According to a further preferred embodiment, the transverse grooves, viewed from above, each consist of a main groove section extending partly in the inner rib section and partly in the outer rib section, and a groove end section formed exclusively in the inner rib section, wherein at least one groove edge is composed of a main edge section extending over the main groove section and an end edge section extending over the groove end section, wherein the edge sections join each other at a bend in the groove edge and form an angle of 150° to 165° with each other, wherein the transverse groove has its maximum width at the bend and from this point the width of the transverse groove decreases continuously towards its ends.wherein the projections and the groove narrowing extend both in the main groove section and in the groove end section, and wherein one of the two converging wall sections, at which one inclined surface terminates, originates from the edge end section, so that the inclined surface has a surface termination adjoining the wall section.

[0019] This special design results in the transverse groove having a groove end section that narrows significantly towards the inside of the tread, which ensures a high stiffness in the profile rib section adjacent to the circumferential groove, advantageous for dry performance.

[0020] The following section discusses preferred variants of the latter preferred design that can be combined with one another.

[0021] A first preferred variant consists of the main groove section having a length, determined within the inner rib section on the outer surface of the rib and projected axially, of 55% to 80% of the length of the transverse groove, also determined within the inner rib section on the outer surface of the rib and projected axially. This is particularly advantageous for wet performance.

[0022] A second preferred variant consists in providing transverse grooves in which the edge end section of one groove edge, viewed in plan view, is composed of a straight, outer edge subsection and an arcuate, inner edge subsection, wherein the inclined surface terminates at a wall section area of ​​the wall section extending from the outer edge subsection and wherein the inner edge subsection has a length, determined on the outer surface of the rib and projected in the axial direction, of preferably 20% to 26% of the length of the groove end section determined on the outer surface of the rib and projected in the axial direction.

[0023] A third preferred variant consists of providing transverse grooves in which the end section of one groove edge, viewed from above, runs straight.

[0024] A fourth preferred variant consists in providing transverse grooves in which the second groove edge is continuously curved, wherein the inclined surface extending from this groove edge, which limits the projection in a radial direction, terminates at a wall section area of ​​the wall section which also limits the projection and extends to the base of the groove, so that the inclined surface has a surface termination adjoining the wall section area.

[0025] A fifth preferred variant provides for transverse grooves in which the second groove edge is composed of a main edge section extending over the main groove section and an end edge section extending over the end groove section, wherein the edge sections enclose an angle of 140° to 150°, with the other of the two converging wall sections, at which the other inclined surface terminates, originating from the end edge section.

[0026] According to a further preferred embodiment, the inclined surfaces on the outer surface of the rib have an axially projected length of 40% to 70%, particularly 45% to 65%, of the axially projected length of the transverse groove. Since the inclined surfaces limit the projections in the radial direction, the length of the inclined surfaces also defines the length of the projections. Inclined surfaces of this length are advantageous for dry performance. At the same time, the projections are limited in length such that the transverse groove has a suitably high water absorption capacity.

[0027] Further features, advantages, and details of the invention will now be described in more detail with reference to the drawing, which schematically shows an embodiment of the invention. The drawing shows... Fig. 1 a simplified top view of a circumferential section of a shoulder-side profile rib of a tread of a vehicle pneumatic tire unfolded into a plane with an embodiment of the invention, Fig. 2 a section along line II-II of the Fig. 1 , Fig. 3 an enlarged top view of detail Z 3 of the Fig. 1 , Fig. 4 a section along line IV-IV of the Fig. 3 , Fig. 5 a cut along line VV of the Fig. 3 , Fig. 6 a section along line VI-VI of the Fig. 3 , Fig. 7 a section along line VII-VII of the Fig. 3 , Fig. 8 a view according to the in Fig. 3 direction of view indicated by arrow S 8, Fig. 9 a view according to the in Fig. 3 direction of view indicated by arrow S 9, Fig. 10 a view according to the in Fig. 3 direction of view indicated by arrow S 10, Fig. 11 a view according to the in Fig. 3 The direction of view indicated by arrow S 11, with the shoulder-side profile rib cut open, Fig. 12 a view according to the in Fig. 3 The direction of view indicated by arrow S 12, with the shoulder-side profile rib cut open, Fig. 13 a view according to the in Fig. 3 direction of view indicated by arrow S 13 and Fig. 14 a section along line XIV-XIV of the Fig. 3 .

[0028] 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 (small transporters with a gross vehicle weight ≤ 3.5 t, light trucks with a gross vehicle weight ≤ 7.5 t).

[0029] Fig. 1 Figure 1 shows a top view of a circumferential section of a shoulder-side profile rib 1 of a vehicle tire tread. The shoulder-side profile rib 1 is bounded on the inside of the tread by a shoulder-side circumferential groove 2, which, in the illustrated embodiment, runs straight in the top view. The lateral edge of the ground-contacting part of the tread is in Fig. 1 characterized by a dashed line L, where the ground-contacting part of the tread corresponds to the statically determined footprint according to ETRTO standards (load at 70% of the maximum bearing capacity at an internal pressure of 85% according to ETRTO standard).

[0030] The shoulder-side circumferential groove 2 is radially aligned to the respective intended profile depth T UR ( Fig. 2 ) carried out, which for the preferred tire type is usually 6.5 mm to 13.0 mm, in particular up to 10.0 mm.

[0031] The shoulder-side profile rib 1 has an outer rib surface 1c located in the periphery of the tread, an inner rib section 1a extending within the ground contact area with a width ba determined in the axial direction at the level of the outer rib surface 1c ( Fig. 3 ) and a rib outer section 1b extending outside the ground contact area and is bounded to the shoulder-side circumferential groove 2 by a rib flank 1d. According to Fig. 2 In the illustrated embodiment, the rib flank 1d has a transition radius 1d', which, viewed in plan view in the axially oriented cross-section (cf. position of line II-II in Fig. 1 ), transitions smoothly into the outer rib surface 1c.

[0032] According to Fig. 1 The shoulder-side profile rib 1 is provided with a plurality of transverse grooves 3, 4 along its circumference, wherein, in the circumferential direction, two transverse grooves 3 alternate with one transverse groove 4. The transverse grooves 3, 4 give the shoulder-side profile rib 1 a block-like structure and, viewed from above and with respect to straight lines L 1 aligned along the greatest groove length, preferably run parallel to each other and to the axial direction at an angle α of 0° to 20°, in particular up to 7°. The angle α of the transverse grooves 3 can deviate from the angle α of the transverse grooves 4 by, in particular, up to 3°, so that, with respect to the lines L 1, the transverse grooves 3 do not run parallel to the transverse grooves 4. Transverse grooves 3, 4, which are immediately successive in the circumferential direction, have distances a 1 of preferably 15.0 mm to 35.0 mm from each other on the outer surface of the rib 1c in the circumferential direction, which are determined to be the smallest possible distances.

[0033] The further design of the transverse grooves 3, 4 is described below using individual transverse grooves 3, 4 as examples.

[0034] According to Fig. 3 The transverse groove 3, 4 ends before the shoulder-side circumferential groove 2, in the exemplary embodiment thus before the radially outer end of the transition rounding 1d' (cf. Fig. 2 ), at an axial distance a 2 (transverse groove 3), a 3 (transverse groove 4) of 4.0 mm and 15.0 mm, respectively, determined on the outer surface 1c of the rib, wherein the distance a 3 is greater than the distance a 2 in the exemplary embodiment. The transverse groove 3, 4 has a length c QR, determined in the inner section 1a of the rib on the outer surface 1c and projected in the axial direction, and a maximum depth t QR (depth at the deepest point) in the radial direction. Fig. 5 and Fig. 7 : Cross groove 3, Fig. 14 : transverse groove 4) from 5.0 mm to 9.0 mm and becomes continuously shallower towards its outer end in a known manner ( Fig. 7 : transverse groove 3).

[0035] The transverse groove 3, 4, viewed from above and in the axial direction, consists of a main groove section 5 extending in the inner rib section 1a and the outer rib section 1b, and a groove end section 6 (transverse groove 3), 7 (transverse groove 4) formed exclusively in the inner rib section 1a. The transverse groove 3, 4 is bounded by a groove base 8, a groove wall 9, and a groove wall 10, wherein the groove wall 9 originates from a groove edge 11 located on the outer rib surface 1c, and the groove wall 10 originates from a groove edge 12 located on the outer rib surface 1c. The orientation of the transverse grooves 3, 4 is such that, in the circumferential direction, a groove edge 11 alternates with a groove edge 12.

[0036] Viewed from above, the groove edge 11 consists of a straight main edge section 11a extending over the main groove section 5 and an end edge section 11b (transverse groove 3) or 11b' (transverse groove 4) extending over the end groove section 6, 7 and has a kink 11k at the mutual connection area of ​​the edge sections 11a, 11b or 11a, 11b', at which the edge sections 11a, 11b or 11a, 11b' enclose an angle β of 150° to 165° measured in plan view over the area of ​​the transverse groove 3, 4. The "division" of the transverse groove 3, 4 into the main groove section 5 and the end groove section 6 or 7 is carried out along a line L 2 running circumferentially through the bend 10k in plan view.Within the ground contact area, the main groove section 5 has a length c1, determined from the outer surface of the rib 1c and projected axially, of 55% to 80% of the length cQR of the associated transverse groove 3, 4. The end groove section 6 or 7 has a length c2, determined from the outer surface of the rib 1c and projected axially, where the length c2 is calculated from the respective length c1 and the distance a2 (transverse groove 3), a3 (transverse groove 4). The length c1 of the main groove section 5 of the transverse groove 3 is preferably 55% to 65% of the length cQR of the transverse groove 3. The length c1 of the main groove section 5 of the transverse groove 4 is preferably 70% to 80% of the length cQR of the transverse groove 4.

[0037] The edge end section 11b (groove edge 11 of the transverse groove 3) is composed, viewed from above, of a straight, outer edge subsection 11b I< on the tread and an at least partially curved, inner edge subsection 11b II< on the tread. The inner edge subsection 11b II< has a length c 3, determined from the outer rib surface 1c and projected axially, of 20% to 26% of the length c 2, wherein the length c 3 is preferably at least 3.0 mm.

[0038] The edge end section 11b' (groove edge 11 of the transverse groove 4) runs straight in top view.

[0039] The groove edge 12 meets the groove edge 11 on the inside of the tread and, viewed from above, consists of a main edge section 12a extending over the main groove section 5 and into the end groove section 6, 7, and an end edge section 12b (transverse groove 3), 12b' (transverse groove 4) extending exclusively within the end groove section 6, 7. The main edge section 12a is slightly curved in plan view such that a straight line L 3 connecting the ends of the main edge section 12a lies within the transverse groove 3, 4.

[0040] In the transverse groove 3, the end edge section 12b runs in an arc-shaped pattern in plan view, its curvature direction coinciding with that of the main edge section 12a, and the end edge section 12b adjoining the main edge section 12a tangentially (without any inflection points). Thus, in the transverse groove 3, the groove edge 12 runs continuously in a curved (arc-shaped) manner without any inflection points.

[0041] In the transverse groove 4, the end edge section 12b' runs straight in plan view and connects to the main edge section 12a via a kink 12k in the groove edge 12. The main edge section 12a forms an angle γ of 140° to 150° with the end edge section 12b', measured in plan view over the area of ​​the transverse groove 4. The angle γ is determined with respect to a tangent (not shown) drawn in plan view to the main edge section 12a and passing through the kink 12k.

[0042] The transverse groove 3, 4 has its maximum circumferential width b QR (width at the widest point) of 3.0 mm to 8.0 mm, specifically 4.0 mm to 7.0 mm, at the bend 11k, 12k between the groove edges 11, 12. Starting from the point with the maximum width b QR, the width of the transverse groove 3, 4 decreases continuously towards its ends.

[0043] How Fig. 3 in combination with Fig. 8 and Fig. 13 As shown, in the area of ​​the inner rib section 1a in the transverse groove 3, 4, there is a top view ( Fig. 3 ) in the extension direction of the transverse groove 3, 4 elongated, flat projection 13, which is also bounded by the groove wall 9, and a top view ( Fig. 3 ) in the extension direction of the transverse groove 3, 4, an elongated, flat projection 14 is formed, which is also bounded by the groove wall 10, wherein the projections 13, 14 rest on the groove base 8. According to Fig. 3 Projections 13 and 14 are located exclusively in the area of ​​the inner rib section 1a, with projections 13 and 14 running partly in the main groove section 5 and partly in the end groove section 6 or 7. How Fig. 8 and Fig. 13 As shown, the transverse groove 3, 4 has a groove narrowing 15 formed by the projections 13, 14, running between them, which according to Fig. 3 extends beyond the ends of the projections 13, 14 on the inside of the tread and over the entire groove end section 6, 7 and up to its end on the inside of the tread.

[0044] According to Fig. 4 The groove walls 9, 10 run in the area outside the projections 13, 14, viewed in plan view in the circumferential direction (cf. position of line IV-IV in Fig. 3 ), to the radial direction at an angle δ of 0° to 8°, in particular of at least 2°.

[0045] According to Fig. 8 and Fig. 13 The projection 13 is bounded by sections of the groove wall 9 and the projection 14 by sections of the groove wall 10. The sections bounding the projections 13, 14 include a chamfer-like inclined surface 9a (projection 13), 10a (projection 14) limiting the projection 13, 14 in the radial direction, a projection flank 9b (projection 13), 10b (projection 14) limiting the projection 13, 14 towards the groove narrowing 15, and an end surface 9c (projection 13), 10c (projection 14) limiting the projection 13, 14 at its end on the outer side of the tread. The groove narrowing 15 is formed by base sections 8a, 8b of the groove base 8, the projecting flanks 9b, 10b and end wall sections 9d, 10d ( Fig. 10 : Wall section 9d of the transverse groove 3) of the groove walls 9, 10 bounded.

[0046] The basic section 8a runs between the projecting flanks 9b, 10b and at depth t QR of the transverse groove 3, 4 (cf. Fig. 7 : transverse groove 3), wherein the basic section 8a according to Fig. 3 at transverse groove 3 it extends into the groove end section 6 and at transverse groove 4 it ends in the main groove section 5. According to Fig. 7 and Fig. 14 The base section 8b connects to the inner end of the base section 8a via an optionally provided transition curve 16 with a radius of up to 1.0 mm, is ramp-shaped and runs, viewed in the longitudinal section running through the transverse groove 3, 4 (cf. position of line VII-VII and XIV-XIV in Fig. 3 ), to the radial direction at a constant angle θ of 50° to 75°, in particular of 60° to 70°, and ends on the inside of the tread at a depth tb of 1.0 mm to 3.0 mm.

[0047] According to Fig. 5 The projecting flanks 9b, 10b, viewed in the circumferential cross-section in plan view, run at an angle η of 0° to 8° to the radial direction, in particular from 2° to 6°.

[0048] According to Fig. 8 and Fig. 13 the end wall section 9d extends from the edge end section 11b ( Fig. 8 , Fig. 10 : transverse groove 3), 11b', ( Fig 13 : transverse groove 4) and the end-side wall section 10d extends from the edge end section 12b ( Fig. 9 : transverse groove 3), 12b' ( Fig. 13 : transverse groove 4).

[0049] According to Fig. 10 The end wall section 9d at the transverse groove 3 is formed from a flat wall section area 9d I< adjoining the outer edge subsection 11b I< and a wall section area 9d II< adjoining the inner edge subsection 11b II<, which in plan view is at least partially arcuate. Fig. 9 The end wall section 10d at the transverse groove 3 is continuously curved in a bow shape in plan view and consists of a wall section area 10d II< adjoining the edge end section 12b and a wall section area 10d I< formed at the projection 14. The wall section areas 9d I< , 9d II< , 10d I< , 10d II< , run, viewed in the circumferentially oriented cross-section, at angles κ of up to 6° to the radial direction ( Fig. 6 : shown for wall section area 9d I< , 10d I< ).

[0050] According to Fig. 13 The end wall sections 9d, 10d at the transverse groove 4 are flat surfaces which meet at an acute angle in plan view (cf. Fig. 3 ).

[0051] How Fig. 8 and Fig. 13 furthermore, the inclined surface 9a extends from a point directly adjacent to the edge end section 11b ( Fig. 8 : transverse groove 3), 11b' ( Fig. 13 : transverse groove 4) subsequent inner section part 11a I< of the main edge section 11a from (cf. Fig. 3 ). The inclined surface 10a extends from a point directly adjacent to the edge end section 12b ( Fig. 8 : transverse groove 3), 12b' ( Fig. 13 : transverse groove 4) adjoining, inner section part 12a I< of the main edge section 12a. (cf. Fig. 3 ). The inner section part 11a I< , 12a I< has a length c 4 projected in the axial direction of 40% to 70%, in particular of 45% to 65%, of the length c QR ( Fig. 3 ) of the transverse groove 3, 4. The length c 4 is therefore the length of the inclined surface 9a, 10a on the outer rib surface 1c.

[0052] The inclined surface 9a, 10a connects to the respective projecting flank 9b, 10b via a straight or slightly curved sharp projecting edge 13a, 14a (cf. Fig. 11, Fig. 12 ) on. According to Fig. 5 The inclined surface 9a, 10a appears when viewed in the circumferentially oriented cross-section (cf. position of line VV in Fig. 3 ), as a straight line which runs at an angle ε of 20° to 55°, in particular 25° to 40°, to the radial direction. The angle ε is preferably constant over the extent of the inclined surface 9a, 10a, so that the inclined surface 9a, 10a is a flat surface or, due to the tire curvature, at least partially slightly curved. Alternatively, the angle ε can vary continuously by up to 2° over the extent of the inclined surface 9a, 10a, so that the inclined surface 9a, 10a is slightly twisted over its extent.

[0053] According to Fig. 11 und Fig. 12 The projecting edge 13a, 14a extends at a depth t VK relative to the level of the outer rib surface 1c in the radial direction, which increases continuously towards the inner side of the tread. The depth t VK has a value t VK,MAX at the inner end of the projecting edge 13a, 14a and a value t VK,MIN at the outer end of the projecting edge 13a, 14a. The value t VK,MAX is 1.4 mm to 4.0 mm, particularly up to 3.0 mm, and the value t VK,MIN is 40% to 65%, particularly 50% to 60%, of the value t VK,MAX.

[0054] The inclined surfaces 9a, 10a, viewed in the circumferential cross-section in plan view, have a width b SF over the extent of the projecting edge 13a, 14a ( Fig. 5 ) which, together with the depth t VK belonging to the projecting edge 13a, 14a, increases continuously towards the inside of the tread. The size of the width b SF results from the design of the depth t VK, i.e. the depth profile of the projecting edge 13a, 14a and the angle ε ( Fig. 5 ) of the inclined surfaces 9a, 10a. How Fig. 8 and Fig. 13 , especially in combination with Fig. 3 , show that the inclined surface 9a runs along the wall section 9d ( Fig. 10 : at the transverse groove 3 on the wall section area 9d I< of the wall section 9d), so that the inclined surface 9a forms a triangular surface outlet 9a I< adjoining the wall section 9d ( Fig. 10 , indicated by a dotted line) the projecting edge 13a on wall section 9d ( Fig. 10 : at the transverse groove 3 on the wall section area 9d I< ) ends. According to Fig. 9 The inclined surface 10a, which co-defines a projection 14 formed in the transverse groove 3, extends to the wall section area 10d I< that also co-defines the projection 14, such that the inclined surface 10a has a surface outlet 10a I< adjoining the wall section area 10d I< and the projection edge 14a ends at the wall section area 10d I< or at the surface outlet 10a I<. According to Fig. 13 The inclined surface 10a, which also borders a projection 14 formed in a transverse groove 4, extends along the wall section 10d.

[0055] According to Fig. 5 The groove narrowing 15, viewed in a top view and oriented circumferentially in cross-section, has a width b RV, which is determined between two lines L 4 running radially through the projecting edges 13a, 14a. The design of the projections 13, 14 is such that the width b RV is 30% to 75%, in particular 40% to 70%, of the maximum width b QR ( Fig. 3 ) of the associated transverse groove 3, 4, wherein the width b RV preferably decreases continuously towards the inside of the tread. The width b RV of the groove narrowing 15 and the maximum width b QR of the transverse groove 3, 4 are preferably matched such that the width b RV is between 1.5 mm and 3.5 mm.

[0056] The invention is not limited to the described embodiment: Both groove edges of the transverse grooves can be free of kinks, so that the transverse grooves do not have groove sections as described in connection with the embodiment. In the other half of the tread, a further shoulder-side profile rib with transverse grooves designed according to the invention can be provided. Bezugszeichenliste

[0057] 1 Shoulder-side profile rib 1a Inner rib section 1b Outer rib section 1c Outer rib surface 1d Rib flank 1d Transition rounding 2 Shoulder-side circumferential groove 3 Transverse groove 4 Transverse groove 5 Main groove section 6 Groove end section 7 Groove end section 8 Groove base 8a Base section 8b Base section 9 Groove wall 9a Slanted surface 9a I< Surface run-out 9b Projection flank 9c End surface 9d Wall section 9d I< Wall section area 9d II< Wall section area 10 Groove wall 10a Slanted surface 10a I< Surface run-out 10b Projection flank 10c End surface 10d Wall section 10d I< Wall section area 10d II< Wall section area 11 Groove edge 11a Main edge section 11a I< Inner section part 11b Edge end section 11b I< Outer edge subsection 11b II< Inner edge subsection 11b' Edge end section 11k Bend 12 Groove edge 12a Main edge section 12a I< Inner section part 12b Edge end section 12b' Edge end section 12k Bend 13 Projection13a Projection edge 14 Projection 14a Projection edge 15 Groove narrowing 16 Transition rounding a1, a2, a3 Spacing ba, b SF, b RV Width b QR Maximum width c1, c2, c3, c4, c QR Length L Line (lateral edge of the ground contact area) L1, L2, L3, L4 Line S8, S9, S10, S11, S12, S13 Arrow (viewing direction) t QR Maximum depth tb, t VK Depth t VK, MIN, t VK, MAX Value T UR Profile depth Z3 Detail α, β, γ, δ, ε, η, θ, κ Angle

Claims

1. Pneumatic vehicle tyre having tread having at least one shoulder-side profile rib (1) which is delimited by a circumferential groove (2) and has a rib outer face (1c) in the tread periphery, and a rib inner portion (1a) extending within the ground contact area and a rib outer portion (1b) extending outside the ground contact area, wherein, in the shoulder-side profile rib (1), transverse grooves (3, 4) extending both in the rib inner portion (1a) and in the rib outer portion (1b) and ending before the circumferential groove (2) are formed with a maximum width (bQR) of 3.0 mm to 8.0 mm determined in the circumferential direction, wherein each transverse groove (3, 4) has two groove edges (11, 12) lying on the rib outer face (1c) and is delimited by a groove base (8) and two groove walls (9, 10) proceeding in each case from one of the groove edges (11, 12), wherein the groove walls (9, 10) have in each case a single oblique face (9a, 10a) which proceeds from the groove edge (11, 12) and is elongate in the direction of extent of the transverse groove (3, 4), characterized in that formed in each transverse groove (3, 4), within the rib inner portion (1a), are two projections (13, 14) which are delimited by portions (9a, 9b, 9c, 10a, 10b, 10c) of the groove walls (9, 10), wherein these portions (9a, 9b, 9c, 10a, 10b, 10c) are in each case one of the oblique faces (9a, 10a), in each case one projection flank (9b, 10b) and in each case one end face (9c, 10c), wherein the oblique face (9a, 10a) delimits the respective projection (13, 14) in the radial direction, and the end face (9c, 10c) delimits the respective projection (13, 14) at its end proximal to the outside of the tread, wherein the oblique faces (9a, 10a) run out at wall portions (9d, 10d) of the groove walls (9, 10) that converge at the end of the transverse groove (3, 4) proximal to the inside of the tread, and wherein a groove constriction (15) of the transverse groove (3, 4), which on the inside proximal to the treads extends beyond the projections (13, 14) and is conjointly delimited by the converging wall portions (9d, 10d) remains between the projections (13, 14), each projection (13, 14) being delimited by the projection flank (9b, 10b) in relation to said groove constriction.

2. Pneumatic vehicle tyre according to Claim 1, characterized in that the projection flanks (9b) adjoin the oblique faces (9a, 10a) by way of projection edges (13a, 14a), wherein the groove constriction (15), when viewed in the cross section aligned in the circumferential direction, has a width (bRV), determined between lines (L4) extending through the projection edges (13a, 14a) in the radial direction, of 30% to 75%, in particular of 40% to 70%, of the maximum width (bQR) of the transverse groove (3, 4).

3. Pneumatic vehicle tyre according to Claim 2, characterized in that the width (bRV) of the groove constriction (15) is 1.5 mm to 3.5 mm.

4. Pneumatic vehicle tyre according to one of Claims 1 to 3, characterized in that the projection flanks (9b, 10b), when viewed in the cross section which in top view is aligned in the circumferential direction, extend in each case at an angle (η) of 0° to 8°, in particular of 2° to 6°, in relation to the radial direction.

5. Pneumatic vehicle tyre according to one of Claims 2 to 4, characterized in that the projection edge (13a, 14a) extends at a depth (tVK) which is determined in the radial direction and increases continuously in the direction of the inside of the tread, wherein the depth (tVK) at the end of the projection edge (13a, 14a) proximal to the inside of the tread has a first value (tVK,MAX) of preferably 1.4 mm to 4.0 mm, particularly preferably of up to 3.0 mm, and at the end of the projection edge (13a, 14a) proximal to the outside of the tread has a second value (tVK,MIN) of preferably 40% to 65%, particularly preferably of 50% to 60%, of the first value (tVK,MAX).

6. Pneumatic vehicle tyre according to one of Claims 2 to 5, characterized in that the oblique faces (9a, 10a), when viewed in the cross section which in top view is aligned in the circumferential direction, have across the extent of the projection edge (13a, 14a) a width (bSF) which increases continuously in the direction of the inside of the tread.

7. Pneumatic vehicle tyre according to one of Claims 1 to 6, characterized in that the converging wall portions (9d, 10d) of the groove walls (9, 10) adjoin a base section (8b) of the groove base (8), which, when viewed in the longitudinal section through the transverse groove (3, 4), at its end proximal to the inside of the tread in the radial direction ends at a depth (tb) of 1.0 mm to 3.0 mm.

8. Pneumatic vehicle tyre according to Claim 7, characterized in that the base section (8b), to which the converging wall portions (9d, 10d) are connected, is viewed in the longitudinal section extending through the transverse groove (3, 4), to the radial direction at a constant angle (θ) of 50° to 75°, in particular of 60° to 70°.

9. Pneumatic vehicle tyre according to one of Claims 1 to 8, characterized in that the transverse grooves (3, 4), when viewed in top view, are each composed of a groove main portion (5) partially extending in the rib inner portion (1a) and partially extending in the rib outer portion (1b) and a groove end portion (6, 7) formed exclusively in the rib inner portion (1a), wherein at least one groove edge (11) is composed of an edge main portion (11a) extending over the groove main portion (5) and an edge end portion (11b, 11b') extending over the groove end portion (6, 7), wherein the edge portions (11a, 11b, 11b') adjoin one another at a kink (11k) of the groove edge (11) and conjointly enclose an angle (β) of 150° to 165°, wherein the transverse groove (3, 4) has its maximum width (bQR) at the kink (11k) and, proceeding from this location, the width of the transverse groove (3, 4) decreases continuously to the end of the latter, wherein the projections (13, 14) and the groove constriction (15) extend both in the groove main portion (5) and in the groove end portion (6, 7), and wherein the one of the two converging wall portions (9d) on which the one oblique face (9a) runs out, proceeds from the edge end portion (11b, 11b') in such a way that the oblique face (9a) has a face run-out (9a) which adjoins the wall portion (9d).

10. Pneumatic vehicle tyre according to Claim 9, characterized in that the groove main portion (5) has a length (c1), determined on the rib outer face (1c) within the rib inner portion (1a) and projected in the axial direction, of 55% to 80% of the length (cQR) of the transverse groove (3, 4), determined on the rib outer face (1c) within the rib inner portion (1a) and projected in the axial direction.

11. Pneumatic vehicle tyre according to Claim 9 or 10, characterized in that provided are transverse grooves (3) in which the edge end portion (11b) of the one groove edge (11), when viewed in top view, consists of a straight edge sub-portion (11bI) which extends proximal to the outside of the tread, and an arcuate edge sub-portion (11bII) which extends proximal to the inside of the tread, wherein the oblique face (9a) ends at a wall portion region (9dI) of the wall portion (9d) that proceeds from the edge sub-portion (11bI) proximal to the outside of the tread, and wherein the edge sub-portion (11bII) proximal to the inside of the tread has a length (c3), determined on the rib outer face (1c) and projected in the axial direction, of preferably 20% to 26% of the length (c2), determined on the rib outer face (1c) and projected in the axial direction, of the groove end portion (6).

12. Pneumatic vehicle tyre according to one of Claims 9 to 11, characterized in that transverse grooves (4) are provided, in which the edge end portion (11b') of the one groove edge (11), viewed in top view, extends in a straight manner.

13. Pneumatic vehicle tyre according to one of Claims 9 to 12, characterized in that transverse grooves (3) are provided, in which the second groove edge (12) is continuously curved, wherein the oblique face (10a), which proceeds from this groove edge (12) and delimits the projection (14) in the radial direction, runs out at a wall portion region (10dI) of the wall portion (10d), which conjointly delimits the projection (14) and extends to the groove base (8), in such a way that the oblique face (10a) has a face run-out (10aI) which adjoins the wall portion region (10dI).

14. Pneumatic vehicle tyre according to one of Claims 9 to 13, characterized in that transverse grooves (4) are provided, in which the second groove edge (12) consists of an edge main portion (12a) extending over the groove main portion (5) and an edge end portion (12b') extending over the groove end portion (7), wherein the edge portions (12a, 12b') enclose an angle (γ) of 140° to 150°, wherein the other of the two converging wall portions (10d), on which the other oblique face (10a) runs out, proceeds from the edge end portion (12b').

15. Pneumatic vehicle tyre according to one of Claims 1 to 14, characterized in that the oblique faces (9a, 10a) have on the rib outer face (1c) a length (c4), projected in the axial direction, of 40% to 70%, in particular of 45% to 65% of the length (cQR), projected in the axial direction, of the transverse groove (3, 4).