PNEUMATIC VEHICLE TIRES

Description

[0001] The invention relates to a pneumatic vehicle tire with a directional tread having at least one central row of tread blocks bordered on both sides by circumferential grooves, said tread blocks being separated from one another by transverse grooves running parallel to one another in plan view and merging into the circumferential grooves, each having a groove centerline, two groove flanks, and a groove base, wherein the transverse grooves each have a first groove section merging into one of the circumferential grooves and extending at an angle of 5° to 25° to the axial direction and relative to the groove centerline, and a second groove section adjoining said first groove section and inclined in the axial direction in the opposite direction to the first groove section, wherein the groove sections first enter the ground with their mutual connecting areas when the tire rolls during forward travel,wherein in each profile block there is formed an additional groove which, in plan view, extends in extension of the first groove section and is narrower than the latter, extending between the transverse groove and the other of the two circumferential grooves.

[0002] Such a pneumatic vehicle tire is known, for example, from US Pat. No. 5,287,905. According to one embodiment, this pneumatic vehicle tire has a directional tread pattern with two central tread block rows, each bordered on both sides by circumferential grooves, with transverse grooves and tread blocks leading into the circumferential grooves. The transverse grooves are, as viewed in plan view, each composed of a first groove section which runs at an angle of approximately 15° to the axial direction and leads into one circumferential groove, a second groove section which adjoins the first groove section and is inclined in the opposite direction to the axial direction, and a third groove section which is inclined in the same direction as the first groove section and leads into the other circumferential groove. In each tread block, as an extension of the first groove section orA narrow additional groove is formed as an extension of the second groove section. The tire is designed to exhibit low tire-road noise while maintaining good dry performance.

[0003] US 2020 / 0376899 A1 discloses a pneumatic vehicle tire which, with the exception of the directional nature of the tread, corresponds to a pneumatic vehicle tire of the type mentioned above. The tread has four tread ribs, with one of the central tread ribs being significantly wider than the other tread ribs. The wider central tread rib is provided with a groove pattern consisting of intersecting transverse grooves and additional grooves. The pneumatic vehicle tire is intended to exhibit good snow performance and good response to steering forces.

[0004] EP 3 300 926 A1 discloses a pneumatic vehicle tire with a tread having two central rows of tread blocks, each delimited by circumferential grooves and divided into tread blocks by transverse grooves, the transverse grooves widening in a funnel shape towards the shoulder-side circumferential groove. The transverse grooves have two groove sections adjoining one another at an obtuse angle, with a base elevation being formed in the end section of one of the groove sections on the inside of the block. In each of the tread blocks, an additional groove is formed which runs between adjacent transverse grooves and divides the respective tread block into two essentially equal-sized block segments, the additional groove widening in a funnel shape and running at an angle of 5° to 15° to the circumferential direction. According to one embodiment, the tread is directional.This tire is intended to be suitable as an all-season tire and is particularly balanced with regard to its handling characteristics, which are primarily determined by the stiffness of the tread, the water drainage capacity and the snow grip.

[0005] In tires of the type mentioned above, the transverse grooves formed on the tread, which have at least a bend in their course due to their groove sections, are primarily responsible for good snow grip properties, especially when cornering. The groove sections lengthen the drainage path to the circumferential grooves and increase the risk of turbulence in the flowing water, so that the water drainage capacity of the transverse grooves is reduced compared to kink-free transverse grooves. The additional grooves formed in the tread blocks, known from EP 3 300 926 A1, cannot compensate to the desired extent for the reduced water drainage capacity caused by the angled groove sections.

[0006] The invention is therefore based on the object of implementing measures in a pneumatic vehicle tire of the type mentioned at the outset which optimally compensate for the reduced water drainage capacity of the transverse grooves, which is caused by the angled "drainage paths" in aquaplaning situations, while maintaining a profile stiffness required for good handling properties.

[0007] The stated object is achieved according to the invention in that the additional groove is designed to be shallower than the first groove section, wherein the groove base of the transverse groove has a base section extending over the entire second groove section, which projects into the first groove section with an end section and is provided with a local depression reaching as far as the groove flanks, which is formed at least partially in the end section or adjacent to the end section, wherein the transverse groove is designed to be shallowest in the region of the base section outside the local depression.

[0008] The design of the additional grooves is therefore specifically tailored to the directional nature of the tread. Since these additional grooves extend from the first groove section, water absorbed by the additional grooves is diverted with minimal turbulence into the first groove section of the transverse groove and from there into the circumferential groove into which this groove section opens, significantly increasing water drainage capacity.

[0009] Because the additional grooves are narrower and shallower than the first groove section, the rigidity of the tread blocks, which is crucial for good handling characteristics, is maintained. The locally shallower transverse grooves stiffen the row of tread blocks and are thus beneficial for handling characteristics. The local deepening increases the volume of the transverse groove or the transverse groove cross-section in the area where the additional groove joins, i.e., in the critical area for water drainage.

[0010] According to a preferred embodiment, the additional groove, viewed in plan view and relative to its groove centerline, extends at an angle to the axial direction that deviates from the angle at which the first groove section extends to the axial direction by at most 10°, in particular by at most 5°, and particularly preferably by at most 2°. This measure contributes to quickly diverting water absorbed by the additional groove into the first groove section of the transverse groove and is therefore of additional benefit for the water drainage capacity in the region of the transverse groove.

[0011] A further preferred embodiment is characterized in that that each tread block has an incoming block edge and a outgoing block edge on the transverse grooves which first enter the ground when the tire rolls when driving forward, the incoming block edge and the outgoing block edge each having a block edge section in each groove section, the additional groove having a first and a second groove edge, the first groove edge adjoining the block edge section of the outgoing block edge located in the first groove section and the second groove edge adjoining the block edge section of the outgoing block edge located in the second groove section.

[0012] Due to groove edges running in this way, the water flows from the additional groove into the transverse groove with particularly low or largely turbulence-free flow, so that water drainage is further improved.

[0013] In the preferred embodiment mentioned above, it is particularly advantageous for the reasons mentioned if the first groove edge, viewed in plan view, runs in a straight line extension of the block edge section located in the first groove section, to which it adjoins.

[0014] According to a further preferred embodiment, the additional groove has a depth of 1.0 mm to 2.0 mm, in particular 1.3 mm to 1.7 mm, and / or a width of 1.0 mm to 2.0 mm, in particular 1.3 mm to 1.7 mm, in the radial direction. These features are also favorable for good water drainage.

[0015] For water drainage, it is furthermore advantageous if the second groove section forms an angle of 100° to 130°, preferably 110° to 120°, particularly preferably 113° to 117°, with the first groove section, relative to the groove center line.

[0016] In the aforementioned preferred embodiment, it is advantageous if the local depression - in relation to its volume - is formed at least largely in the second groove section.

[0017] Furthermore, in the aforementioned preferred embodiment, it is advantageous if the local depression has a depth of 0.5 mm to 1.5 mm, in particular of 0.8 mm to 1.2 mm, and / or a length of 1.5 mm to 4.0 mm determined along the groove center line.

[0018] Furthermore, in the aforementioned preferred embodiment, it is advantageous if the end section of the base section—relative to the groove centerline m QR—has a length projected in the axial direction of 40% to 60%, in particular of at least 50%, of the length of the first groove section determined in an analogous manner. In the area outside the end section of the base section, a deeper junction area to the circumferential groove remains in the first groove section, whereby the rigidity of the tread block row and the water drainage capacity of the transverse grooves running within it are particularly advantageously balanced.

[0019] Furthermore, in the aforementioned preferred embodiment, it is advantageous if the base section extends outside the local depression at a constant depth of 40% to 60% of the profile depth, determined in the radial direction. This contributes to the balance of the aforementioned properties.

[0020] Furthermore, in the aforementioned preferred embodiment, it is advantageous if the groove base of the transverse groove has a base section that runs exclusively in the first groove section, which is at most 1.0 mm to 2.0 mm from the tread depth level in the radial direction and preferably slopes downwards toward the circumferential groove into which the first groove section opens. This base section is located in the aforementioned, deeper junction area of ​​the transverse groove with the circumferential groove and is advantageous for the water drainage capacity of the transverse groove.

[0021] According to a further preferred embodiment, the second groove section extends to the circumferential groove into which the first groove section does not open.

[0022] According to an alternative preferred embodiment, a third groove section adjoins the second groove section within the profile block row, which third groove section extends to the circumferential groove into which the first groove section does not open, and which is inclined in the same direction as the first groove section with respect to the axial direction, wherein the third groove section preferably a. is narrower than the first groove section and narrower than the second groove section and / or b. with respect to the groove center line, runs at an angle to the axial direction which deviates by a maximum of 5° from the angle at which the first groove section runs to the axial direction and / or c. forms an obtuse angle with the second groove section with respect to the groove center line and / or d. has a length projected in the axial direction and related to the groove center line of 15% to 30%, in particular 20% to 25%, of the width of the middle tread block row projected in the axial direction.

[0023] The third groove section gives the transverse groove a zigzag shape and is particularly beneficial for snow grip. The third groove section advantageously enhances the water drainage capacity of the transverse groove due to the specially designed additional grooves, which, as explained in the context of the solution to the problem, have little impact. The additional grooves primarily increase the ingress of water into the first groove section, while the third groove section connects to the second groove section.

[0024] Furthermore, it is advantageous for the drainage capacity of the tread if the first groove section opens into a circumferential groove that borders the middle row of tread blocks on the outside of the tread and the additional groove opens into a circumferential groove that borders the middle row of tread blocks on the inside of the tread.

[0025] Further features, advantages and details of the invention will now be described in more detail with reference to the drawing, which schematically shows exemplary embodiments of the invention. Fig. 1 a simplified plan view of a circumferential section of a tread of a pneumatic vehicle tire with a first embodiment of the invention, Fig. 2 an enlarged top view of the detail Z 2 of the Fig. 1 , Fig. 3 a reduced section along line III-III of the Fig. 2 , Fig. 4 a reduced section along lines IV-IV of the Fig. 2 , Fig. 5 a reduced section along the line VV of the Fig. 2 , Fig. 6 a reduced section along line VI-VI of the Fig. 2 , Fig. 7 a reduced section along the line VII-VII of the Fig. 2 , Fig. 8 a reduced section along the line VIII-VIII of the Fig. 2 and Fig. 9 a plan view of a profile block of a tread with a second embodiment of the invention.

[0026] Pneumatic vehicle tires designed according to the invention are tires for motor vehicles, in particular for multi-track motor vehicles, and preferably tires of radial design for passenger cars, vans or light trucks (light trucks with a GVW ≤ 7.5 t), the tires being intended for driving under winter driving conditions.

[0027] Fig. 1 shows a circumferential section of a tread 1 of a pneumatic vehicle tire. The tread 1 has a directional tread pattern, and the pneumatic vehicle tire is to be mounted on the vehicle in such a way that it has the rolling direction symbolized by the arrow R when driving forward. The tire's equatorial plane is indicated by a dashed line AA.

[0028] The tread 1 has, in each tread half, a central tread block row 2 and a shoulder-side tread rib 3, wherein the shoulder-side tread ribs 3 are shown only schematically and can be designed in a manner known per se. The central tread block rows 2 are separated from one another by a central circumferential groove 4, which is straight in plan view and runs along the tire equatorial plane (line AA), and from the adjacent shoulder-side tread rib 3 by a shoulder-side circumferential groove 5, which is straight in plan view. The circumferential grooves 4, 5 are provided with the respective intended tread depth TP ( Fig. 3 , Fig. 7 ), which is usually 6.5 mm to 13.0 mm for the preferred tire type.

[0029] Each central tread block row 2 has a width b PB at the tread periphery in the axial direction and is divided into tread blocks 6 by a plurality of transverse grooves 7, which in the exemplary embodiment are zigzag-shaped and parallel to one another in plan view and which run between the central circumferential groove 4 and the corresponding shoulder-side circumferential groove 5. The transverse grooves 7 are formed in the central tread block rows 2 in such a way that one central tread block row 2 is symmetrical to the other central tread block row 2 with respect to the tire equatorial plane (line AA). The further design of the tread blocks 6 and the transverse grooves 7 is described below using an individual transverse groove 7 and the tread blocks 6 adjacent to the transverse groove 7 and with reference to Fig. 2 bis Fig. 8 explained.

[0030] According to Fig. 2 The transverse groove 7 is composed of a groove section 7a leading into the shoulder-side circumferential groove 5, a groove section 7b ending on both sides within the middle tread block row 2, and a groove section 7c leading into the central circumferential groove 4. The groove center line m QR following the groove course (coincides with the section line VII-VII) is shown.

[0031] The groove section 7a runs straight when viewed from above and - with respect to the groove center line m QR - at an angle α of 5° to 25°, in particular of 10° to 20°, preferably of 13° to 17°, to the axial direction and has a length la projected in the axial direction and with respect to the groove center line m QR of 40% to 60%, in particular of 45% to 55%, of the width b PB of the middle profile block row 2.

[0032] The groove section 7b runs straight when viewed from above, is inclined in the opposite direction to the groove section 7a with respect to the axial direction and encloses with it - based on the groove center line m QR - an angle β of 100° to 130°, preferably of 110° to 120°, particularly preferably of 113° to 117°.

[0033] The inclination of the groove sections 7a, 7b is such that when the tire rolls forward (arrow R), the adjacent, block-inside ends of the groove sections 7a, 7b penetrate the ground before the other ends. The groove sections 7a, 7b therefore penetrate the ground via their mutual connecting area.

[0034] The groove section 7c also runs straight when viewed from above, is inclined in the same direction as the groove section 7a with respect to the axial direction, runs - with respect to the groove center line m QR - at an angle γ to the axial direction, which deviates from the angle α of the groove section 7a by a maximum of 5°, encloses an obtuse angle δ with the groove section 7b - with respect to the groove center line m QR - and has a length lc projected in the axial direction, related to the groove center line m QR, of 15% to 30%, in particular of 20% to 25%, of the width b PB of the middle profile block row 2.

[0035] The profile blocks 6 each have adjacent transverse grooves 7 (in Fig. 2 The tread pattern has a block edge 9 on one side (shown for a transverse groove 7) and a block edge 10 on the other adjacent transverse groove 7, whereby when the tire rolls forward (arrow R), the block edge 9 of each tread block 6 enters the ground before the block edge 10. The block edge 9 is therefore also referred to below as the "incoming block edge 9" and the block edge 10 is also referred to below as the "outgoing block edge 10". The block edges 9, 10 are each composed of a block edge section 9a, 10a running in the groove section 7a, a block edge section 9b, 10b running in the groove section 7b and a block edge section 9c, 10c running in the groove section 7c, whereby the block edge sections 9a, 9b, 9c, 10a, 10b, 10c each run straight in plan view.

[0036] The transverse groove 7 has a width b QR determined between the block edges 9, 10 or between the corresponding block edge sections 9a, 9b, 9c, 10a, 10b, 10c in plan view perpendicular to the groove center line m QR. In the groove section 7a, the width b QR decreases continuously from the end of the groove section 7a located inside the tread block row 2 in the direction of the shoulder-side circumferential groove 5 over the extent of the block edge sections 9a, 10a, wherein the width b QR in the groove section 7a at the narrowest point Sa,min is 2.5 mm to 4.0 mm, in particular 3.5 mm to 4.5 mm, and at the widest point Sa,max is 110% to 130%, in particular 115% to 125%, of the width b QR at the narrowest point Sa,min. In the groove section 7b, the width b QR decreases continuously in the direction of the groove section 7c, the width b QR in the groove section 7b at the narrowest point S b,min being 85% to 95% of the width b QR at the point S a,min.In the groove section 7c, the width b QR is constant and smaller than at the point S b,min and is at least 1.5 mm, preferably at least 2.0 mm.

[0037] The transverse groove 7 is delimited over all groove sections 7a, 7b, 7c by a groove flank 11 extending from the incoming block edge 9, a groove flank 12 extending from the outgoing block edge 10 and a groove base 13. The groove flanks 11, 12, viewed in the cross-section oriented perpendicular to the groove center line m QR, extend to the radial direction at an angle ε ( Fig. 4 bis Fig. 6 ) from 0° to 7°, whereby the angle ε of the groove flanks 11, 12 in the groove sections 7a, 7b ( Fig. 4, Fig. 5 ) preferably up to 5° and in the groove section 7c ( Fig. 6 ) is preferably up to 3°.

[0038] The groove base 13 has a base section 13', which extends over the groove sections 7c, 7b and projects into the groove section 7a with an end section 13'a, and a base section 13" which runs exclusively in the groove section 7a. The base section 13' is provided in the groove section 7b with a local depression 14 which is trapezoidal in plan view and borders on the end section 13'a. Alternatively, the local depression 14 (cf. Fig. 7 ) may be formed at least partially in the end section 13'a. The end section 13'a has - relative to the groove center line m QR - a length l' a projected in the axial direction of 40% to 60%, in particular of at least 50%, of the length la of the groove section 7a. As Fig. 7 shows, the base section 13', including its end section 13'a, runs in the area outside the recess 14 at a constant depth t 1 determined in the radial direction of 40% to 60% of the profile depth TP . The recess 14 has a depth tv of 0.5 mm to 1.5 mm, in particular of 0.8 mm to 1.2 mm, relative to the level of the base section 13' in the radial direction, as well as a length Iv determined along the groove center line m QR at the level of the base section 13'a (cf. position of the section line VII-VII in Fig. 2 ) from 1.5 mm to 4.0 mm. The base section 13", which runs exclusively in the groove section 7a, has, in its area closest to the end section 13'a of the base section 13', a distance a 1 of 1.0 mm to 2.0 mm, determined in the radial direction, from the level of the tread depth and drops in the direction of the shoulder-side circumferential groove 5 to the tread depth TP.

[0039] How Fig. 1 further shows, in each profile block 6 an additional groove 8 is formed running between a transverse groove 7 and the central circumferential groove 4, wherein the additional grooves 8 located within a central profile block row 2 run parallel to each other in plan view. Fig. 2 the additional groove 8, viewed in plan view, runs straight and in extension of the groove section 7a and opens into the groove section 7b. The additional groove 8 has a groove center line m N and, on the periphery of the associated profile block 6, two groove edges 8a, 8b which, viewed in plan view, run straight and parallel to one another, wherein the groove edge 8a adjoins the end of the block edge section 10a located inside the profile block 6 and wherein the groove edge 8b meets the block edge section 10b. The additional groove 8, viewed in plan view and relative to a groove center line m N , runs to the axial direction at an angle α' which deviates from the angle α of the first groove section 7a by at most 10°, in particular by at most 5°, particularly preferably by at most 2°.In the embodiment shown, the angle α' between the groove center line m N and the axial direction is selected such that the groove edge 8a, in plan view, adjoins the block edge section 10a without any kinks and therefore runs in a straight line continuation from it.

[0040] According to Fig. 8 the additional groove 8, viewed in cross-section, is U-shaped and has a width b N determined between and in plan view perpendicular to the groove edges 8a, 8b (cf. Fig. 2 ) of 1.0 mm to 2.0 mm, in particular of 1.3 mm to 1.7 mm, a depth t N determined in the radial direction of 1.0 mm to 2.0 mm, in particular of 1.3 mm to 1.7 mm, as well as two groove flanks 8c extending from the groove edges 8a, 8b, which, viewed in the cross-section of the additional groove 8, run at an angle θ of 0° to 6°, in particular of at least 2°, to the radial direction. The additional groove 8 is therefore narrower and shallower over its entire extent than the groove section 7a.

[0041] As already explained, the groove flank 12 of the transverse groove 7, which adjoins the outgoing block edge 10, runs in the groove section 7a at an angle ε ( Fig. 4 ) and therefore has a groove flank section 12a ( Fig. 2 ). Preferably, the angle ε of the groove flank section 12a corresponds to the angle θ ( Fig. 8 ) of the groove flank 8c adjoining the groove edge 8a, so that this groove flank 8c runs in a planar continuation of the groove flank section 12a, thus merging into it without kinks.

[0042] How Fig. 1 As shown, the additional grooves 8 divide the profile blocks 6 into a block segment 6a and a block segment 6b having a smaller outer surface than the latter. The block segment 6a is formed by sections of the circumferential grooves 4, 5, an additional groove 8, and the groove section 7a adjoining it (cf. Fig. 2 ) and the corresponding transverse groove 7. The block segment 6b is bounded by a section of the central circumferential groove 4, the groove sections 7b, 7c of a transverse groove 7 (cf. Fig. 2 ) and the corresponding additional groove 8.

[0043] Fig. 9 shows a view of profile blocks 6, which is a variant of the profile block 6 according to the first embodiment (cf. Fig. 1 ) and differ from it in that three incisions 15a are formed in the block segment 6a and one incision 15b is formed in the block segment 6b. The incisions 15a run in the opposite direction to the additional groove 8 when viewed in plan view and with respect to the axial direction and traverse the block segment 6a. The incision 15b runs parallel to the additional groove 8 when viewed in plan view. The incisions 15a, 15b each have a width of 0.4 mm to 1.2 mm and, in the radial direction at their deepest point, a depth of 75% to 100%, in particular of up to 95%, of the profile depth TP ( Fig. 3 , Fig. 7 ).

[0044] The invention is not limited to the described embodiments.

[0045] In particular, the transverse grooves 7 can be composed exclusively of the groove sections 7a, 7b, so that the transverse grooves, together with the groove section 7b, open into the corresponding circumferential groove. The groove section 7c is thus optional. Furthermore, the transverse grooves 7 can have a constant width. The additional groove 8 can open into the transverse groove 7, more precisely the groove section 7b, as an extension of the groove section 7a, such that the additional groove 8 interrupts the block edge section 10b at its end section located at the block edge section 10, and therefore both groove edges 8a, 8b adjoin the block edge section 10b. In this embodiment, the groove edge 8a does not adjoin the end of the block edge section 10a. The tread has at least one central tread block row, which is provided with transverse grooves and additional grooves in the manner described. List of reference numbers

[0046] 1Tread 2Central tread block row 3Shoulder-side tread rib 4Central circumferential groove 5Shoulder-side circumferential groove 6Tread block 6a, 6bBlock segment 7Transverse groove 7aGroove section 7bGroove section 7cGroove section 8Additional groove 8a, 8bGroove edge 8cGroove flank 9Block edge 9a, 9b, 9cBlock edge section 10Block edge 10a, 10b, 10cBlock edge section 11Groove flank 12Groove flank 12aGroove flank section 13Groove bottom 13', 13"Base section 13'aEnd section 14Recess 15a, 15bIncision RParrow (rolling direction) A-ALine (tire equatorial plane) a 1 Distance b PB , b QR , b N Width la , l' a , lc , l V Length m N Groove center line m QR Groove center line S a, min , S b, min narrowest point S a, max widest point t 1 ,t N Depth TP Profile depth Z 2 Detail α, α', β, γ, δ, ε, θAngle

Claims

1. Pneumatic vehicle tyre having a directional tread with at least one central row of profile blocks (2), delimited on both sides by circumferential grooves (4, 5), with profile blocks (6) which in top view are separated from one another by transverse grooves (7) that run parallel to one another and open into the circumferential grooves (4, 5) and have in each case one groove centreline (mQR), two groove flanks (11, 12) and one groove base (13), wherein the transverse grooves (7) have in each case a first groove portion (7a) which opens into the one of the circumferential grooves (5) and in relation to the axial direction and in terms of the groove centreline (mQR) runs at an angle (α) of 5° to 25°, and adjoining thereto a second groove portion (7b) which in the axial direction is inclined opposite to the first groove portion (7a), wherein the groove portions (7a, 7b) by way of their mutual connection region enter the ground first when the tyre rolls during forward travel, wherein formed in each profile block (6) is an additional groove (8) which, in top view, runs as an extension of the first groove portion (7a) and which is embodied to be narrower in comparison thereto and extends between the transverse groove (7) and the other one of the two circumferential grooves (4), characterized in that the additional groove (8) is embodied to be shallower in comparison to the first groove portion (7a), wherein the groove base (13) of the transverse groove (7) has a base portion (13') which extends over the complete second groove portion (7b) and by way of an end portion (13'a) protrudes into the first groove portion (7a) and is provided with a local depression (14) which reaches up to the groove flanks (12, 13) and is at least partially formed in the end portion (13'a) or so as to be contiguous to the end portion (13'a), wherein the transverse groove (7) is embodied to be shallowest in the region of the base portion (13') outside the local depression (14).

2. Pneumatic vehicle tyre according to Claim 1, characterized in that the additional groove (8), viewed in top view and in terms of its groove centreline (mN), runs at an angle (α') in relation to the axial direction, which deviates by at most 10°, in particular by at most 5°, particularly preferably by at most 2°, from the angle (α) at which the first groove portion (7a) runs in relation to the axial direction.

3. Pneumatic vehicle tyre according to Claim 1 or 2, characterized in that each profile block (6) on the transverse grooves (7) when the tyre rolls during forward travel (arrow R) has an incoming block edge (9) first entering the ground, and an outgoing block edge (10), wherein the incoming block edge (9) and the outgoing block edge (10) in each groove portion (7a, 7b) have in each case one block edge portion (9a, 9b, 10, 10b), wherein the additional groove (8) has a first and a second groove edge (8a, 8b), wherein the first groove edge (8a) adjoins the block edge portion (10a) of the outgoing block edge (10) located in the first groove portion (7a), and the second groove edge (8b) adjoins the block edge portion (10b) located in the second groove portion (7b) of the outgoing block edge (10).

4. Pneumatic vehicle tyre according to Claim 3, characterized in that the first groove edge (8a), in top view, extends in a rectilinear extension of the adjoining block edge portion (10a) located in the first groove portion (7a).

5. Pneumatic vehicle tyre according to one of Claims 1 to 4, characterized in that the additional groove (8) has in the radial direction a depth (tN) of 1.0 mm to 2.0 mm, in particular of 1.3 mm to 1.7 mm and / or a width (bN) of 1.0 mm to 2.0 mm, in particular of 1.3 mm to 1.7 mm.

6. Pneumatic vehicle tyre according to one of Claims 1 to 5, characterized in that the second groove portion (7b) conjointly with the first groove portion (7a) - in terms of the groove centreline (mQR) - encloses an angle (β) of 100° to 130°, preferably of 110° to 120°, especially preferably of 113° to 117°.

7. Pneumatic vehicle tyre according to one of Claims 1 to 6, characterized in that the local depression (14) - in terms of its volume - is formed at least largely in the second groove portion (7b).

8. Pneumatic vehicle tyre according to one of Claims 1 to 7, characterized in that the local depression (14) has a depth (tv) of 0.5 mm to 1.5 mm, in particular of 0.8 mm to 1.2 mm, and / or a length (lV) of 1.5 mm to 4.0 mm determined along the groove centreline (mQR).

9. Pneumatic vehicle tyre according to one of Claims 1 to 8, characterized in that the end portion (13'a) of the base portion (13') - in terms of the groove centreline mQR - has a length (l'a) projected in the axial direction of 40% to 60%, in particular of at least 50%, of the length (la) of the first groove portion (7a) determined in an analogous manner.

10. Pneumatic vehicle tyre according to one of Claims 1 to 9, characterized in that the base portion (13') outside the local depression (14) extends at a constant depth (t1) of 40% to 60% of the profile depth (TP) determined in the radial direction.

11. Pneumatic vehicle tyre according to one of Claims 1 to 10, characterized in that the groove base (13) of the transverse groove (7) has a base portion (13") which extends exclusively in the first groove portion (7a) and from the height level of the profile depth (T1) has a spacing (a1) in the radial direction of at most 1.0 mm to 2.0 mm, and preferably descends in the direction towards the circumferential groove (5) into which the first groove portion (7a) opens.

12. Pneumatic vehicle tyre according to one of Claims 1 to 11, characterized in that the second groove portion (7b) extends to that circumferential groove (4) into which the first groove portion (7a) does not open.

13. Pneumatic vehicle tyre according to one of Claims 1 to 11, characterized in that a third groove portion (7c) adjoins the second groove portion (7b) within the profile block row (2), said third groove portion (7c) extending up to the circumferential groove (4) into which the first groove portion (7a) does not open, and being inclined in relation to the axial direction in the same direction as the first groove portion (7a), wherein the third groove portion (7) preferably a. is narrower than the first groove portion (7a) and narrower than the second groove portion (7b), and / or b. in terms of the groove centreline (mQR) - extends in relation to the axial direction at an angle (γ) which deviates from the angle (α) at which the first groove portion (7a) extends in relation to the axial direction, by at most 5°, and / or c. conjointly with the second groove portion (7b) - in terms of the groove centreline (mQR) - encloses an obtuse angle (δ), and / or d. in terms of the groove centreline (mQR) has a length (lc), projected in the axial direction, of 15% to 30%, in particular of 20% to 25%, of the width (bPB), projected in the axial direction, of the central profile block row (2).

14. Pneumatic vehicle tyre according to one of Claims 1 to 13, characterized in that the first groove portion (7a) opens into a circumferential groove (5) delimiting the central profile block row (2) on the outside of the tread, and the additional groove (8) opens into a circumferential groove (4) delimiting the central profile block row (2) on the inside of the tread.