PNEUMATIC VEHICLE TIRES

Description

[0001] The invention relates to a pneumatic vehicle tire with a tread with at least one shoulder-side profile rib delimited by a circumferential groove with transverse grooves ending in front of the circumferential groove with transverse groove flanks and transverse groove edges, wherein an additional groove adjoins the tread-inside end of each transverse groove, which additional groove ends within the shoulder-side profile rib, runs at an angle of up to ± 35° to the circumferential direction in plan view, has an inside tread groove flank ending at a tread-inside groove edge, an outside tread groove flank ending at a tread-outside groove edge and a groove base with a mouth edge on the transverse groove.

[0002] Such a pneumatic vehicle tire is known, for example, from DE 10 2014 225 621 A1. The pneumatic vehicle tire has a tread with at least one shoulder-side tread rib defined by a circumferential groove and with transverse grooves ending in front of the circumferential groove. At the inner end of the transverse grooves, additional grooves open at an angle of up to ± 10° to the circumferential direction. These additional grooves have a depth of 1.5 mm to 3.0 mm, at least over most of their radial extension, and a width that increases toward the transverse groove. The additional grooves improve the drainage of the tread rib without compromising the rigidity of the shoulder-side tread rib.

[0003] Furthermore, pneumatic vehicle tires are known that have a tread with shoulder-side tread ribs and transverse grooves, with chamfers extending toward the transverse groove edge on the transverse groove flanks, which is particularly beneficial for braking performance on dry road surfaces. Such a tire is disclosed, for example, in DE 10 2015 202 614 A1.

[0004] EP 2 631 087 B1 discloses a pneumatic vehicle tire with a directional tread comprising a central tread rib and two relatively wide, shoulder-side tread ribs. The central tread rib is free of any negative tread contours. The shoulder-side tread ribs are provided with V-shaped transverse grooves extending across the tread width. The transverse grooves in one shoulder-side tread rib are inclined in the opposite direction to those in the other shoulder-side tread rib with respect to the circumferential direction. The transverse grooves penetrate the ground first with their inner tread ends as the tire rolls forward.The transverse grooves include transverse grooves that flow into the respective circumferential groove and first and second transverse grooves located between these grooves, which terminate closed on both sides within the shoulder-side tread ribs. A first and a second transverse groove are located in the area between successive, flowing transverse grooves. Viewed from above, the first transverse grooves are each composed of two groove sections that form an obtuse angle to each other. This pneumatic vehicle tire is intended to provide improved high-speed performance, particularly ensuring good transmission of steering forces when driving on racetracks.

[0005] EP 3 388 256 B1 discloses a pneumatic vehicle tire with a tread having a shoulder-side profile rib with transverse grooves with a main section running within the ground contact patch, wherein the transverse groove terminates as a flat depression outside the ground contact patch. The flat depression has a width of at least 140% of the width of the main section. The main section is provided on a groove wall with a chamfer running towards the groove edge, which chamfer has a main chamfer section in the extension direction of the transverse groove and, outside the ground contact patch, a chamfer end section that is wider than the main chamfer section. The chamfer end section is delimited on the outer surface of the profile rib by an edge section of the corresponding groove edge, wherein the edge section has a kink that widens the transverse groove and wherein each chamfer end section terminates along the flat depression.The tire has good aquaplaning performance, especially when cornering.

[0006] It is well known that conflicting objectives regularly arise in the design of tread patterns – improving one tire property leads to a deterioration of another. One of these conflicting objectives is between dry performance and wet performance.

[0007] The invention is based on the object of improving the dry and wet performance of a pneumatic vehicle tire of the type mentioned at the beginning as equally as possible, thus resolving the corresponding conflict of objectives at a technically higher level than before.

[0008] The stated object is achieved according to the invention in that on at least one transverse groove flank of each transverse groove, a chamfer extending to the transverse groove edge and forming an inclined surface is attached to the transverse groove flank, wherein at the junction of the additional groove, an outwardly curved corner surface is formed which runs between its groove flank on the outside of the tread and the chamfer attached to the transverse groove flank, which corner surface has a radially outer boundary edge on the rib outer surface which runs between the groove edge of the additional groove on the outside of the tread and the transverse groove edge to which the chamfer extends, and a radially inner boundary edge on the transverse groove flank to which the chamfer is attached, wherein the corner surface is curved in such a way thatthat its radially outer boundary edge is curved in plan view and its radially inner boundary edge is curved radially inwards from the chamfer edge and towards the mouth edge of the groove base to the additional groove.

[0009] According to the invention, the known concept of chamfers on transverse grooves is thus specially integrated into pneumatic vehicle tires of the type mentioned above and enhanced by specially designed, outwardly curved corner surfaces. The chamfers are particularly advantageous for dry performance. The curved corner surfaces enable a particularly low-turbulence water flow from the additional grooves into the transverse grooves and locally increase the cross-section of the additional groove in the area where they join, which is beneficial for the water absorption capacity of the transverse grooves. Furthermore, the curved corner surfaces round off the corner areas where the grooves intersect, effectively counteracting curling of the groove edges located there. Both dry and wet performance are therefore improved, and the corresponding conflict of objectives is resolved at a high technical level.

[0010] According to a preferred embodiment, the additional groove is inclined in plan view such that its end adjacent to the transverse groove is closer to the lateral edge of the ground contact patch than its other end. This promotes water flow toward the lateral edge of the ground contact patch and is therefore an additional advantage for wet performance.

[0011] According to a further preferred embodiment, the radially outer boundary edge of the corner surface has a first length projected in the axial direction of 1.0 mm to 3.0 mm and a second length projected in the circumferential direction of 1.0 mm to 3.0 mm. The corner surface is therefore not overly large and therefore has little impact on the net contact area of ​​the tread, which is beneficial for dry performance.

[0012] The water flow from the additional groove into the transverse groove is further improved with regard to the local drainage behavior if the corner surface is continuously connected to the chamfer attached to the transverse groove flank as well as to the groove flank of the additional groove on the outside of the tread, and if the radially outer boundary edge of the corner surface is continuously connected to the transverse groove edge to which the chamfer extends as well as to the groove edge of the additional groove on the outside of the tread.

[0013] A further preferred embodiment is characterized in that the chamfer edge of the chamfer applied to the transverse groove flank extends at a constant depth, determined in the radial direction, of 0.5 mm to 2.0 mm, in particular of 1.0 mm to 1.5 mm. A chamfer designed in this way is advantageous for dry performance.

[0014] According to a further preferred embodiment, the additional groove—at the level of the rib outer surface—has a length projected in the circumferential direction relative to its groove centerline of 10.0 mm to 25.0 mm, in particular 15.0 mm to 20.0 mm, and / or a particularly constant width measured perpendicular to its groove centerline of 0.5 mm to 4.0 mm, in particular 1.0 mm to 3.5 mm, particularly preferably 1.5 mm to 3.0 mm. An additional groove designed in this way has a high water absorption capacity, which is advantageous for wet performance. The net contact area of ​​the tread is hardly reduced—compared, for example, with conventional transverse grooves—which is beneficial for dry performance.

[0015] According to a further preferred embodiment, the additional groove in the region of the groove base has a depth determined in the radial direction, increasing toward the mouth edge of the groove base, which has a value of 2.0 mm to 4.0 mm, in particular 2.5 mm to 3.5 mm, at the mouth edge. The depth, which increases toward the transverse groove, promotes water drainage from the additional groove into the transverse groove. Due to the fact that the additional groove is not too deep, its effects on the stiffness of the tread rib are kept particularly low, which in turn is advantageous for dry performance.

[0016] In the latter embodiment, it is advantageous if the depth of the additional groove in the area of ​​the groove base at the shallowest point of the additional groove has a value of up to 1.0 mm, in particular from 0.5 mm to 1.0 mm, or if the additional groove, together with its groove base, tapers to the outer surface of the rib at the end facing away from the transverse groove. The above-mentioned technical effect is thereby enhanced.

[0017] According to a further preferred embodiment, the angle at which the additional groove extends to the circumferential direction is up to ± 25°, in particular from ± 10° to ± 20°. This further promotes water drainage from the additional groove into the transverse groove.

[0018] According to a further preferred embodiment, it is provided that the additional groove runs straight in plan view, which also promotes the drainage of water from the additional groove into the transverse groove.

[0019] In the latter preferred embodiment, a preferred variant is that the corner surface, viewed in each sectional plane oriented in the radial direction and running perpendicular to the groove center line of the additional groove in plan view, is curved and / or that the corner surface, viewed in each sectional plane oriented in the radial direction and running parallel to the groove center line of the additional groove in plan view, appears as a straight line.

[0020] A further preferred embodiment is characterized in that the transverse groove, at its inner tread end, has a curved end flank extending between the inner tread flank of the additional groove and the transverse groove flank opposite the corner surface. This curved end flank continuously adjoins the transverse groove flank and continuously adjoins the inner tread flank of the additional groove. On the outer rib surface, this curved boundary edge continuously adjoins the inner tread edge of the additional groove and continuously adjoins the corresponding transverse groove edge. The curved flank interacts with the additional groove and the curved corner surface in a particularly advantageous manner with regard to a low-turbulence water flow from the additional groove into the transverse groove and thus contributes to a further improvement in wet performance.

[0021] According to a further preferred embodiment, the chamfer attached to the transverse groove flank, viewed in cross-section perpendicular to the corresponding transverse groove edge, extends at an angle of 35° to 55°, in particular 40° to 50°, to the radial direction. Such chamfers effectively counteract the "rolling" of the corresponding transverse groove edges, thus improving dry performance.

[0022] Furthermore, it is advantageous for dry performance if the chamfer on the transverse groove flank extends at least to the lateral edge of the tread's ground contact area.

[0023] Further features, advantages and details of the invention will now be explained in more detail with reference to the drawing, which schematically shows an embodiment of the invention. Fig. 1 a plan view of a circumferential section of a shoulder-side region of a tread of a pneumatic vehicle tire with an embodiment variant of the invention, Fig. 2 a section along the line II-II in Fig. 1 , Fig. 3 an enlarged top view of the detail Z 3 in Fig. 1 , Fig. 4 a section along the line IV-IV in Fig. 3 , Fig. 5 a section along the line VV in Fig. 3 , Fig. 6 a section along the line VI-VI in Fig. 3 , Fig. 7 a further enlarged plan view of the detail Z 7 in Fig. 3 , Fig. 8 a section along the line VIII-VIII in Fig. 7 , Fig. 9 a section along the line IX-IX in Fig. 7 , Fig. 10 an enlarged view according to the Fig. 7 direction of view indicated by arrow S 10, Fig. 11 an enlarged section along the line XI-XI of the Fig. 7 and Fig. 12 an enlarged section along the line XII-XII of the Fig. 7 .

[0024] 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).

[0025] Fig. 1 shows a plan view of a circumferential section of a circumferential shoulder-side tread rib 1 belonging to a tread of a pneumatic vehicle tire, which tread is defined by a shoulder-side circumferential groove 2. The lateral edge of the ground contact patch (determined with a tire mounted on a standard rim, loaded at 70% of the maximum load capacity, internal pressure 85% of the standard pressure, according to ETRTO standards) is indicated by a dashed line 1. The area of ​​the tread not shown can be designed in a known manner.

[0026] In the embodiment shown, the shoulder-side circumferential groove 2 runs straight in plan view, is radially in the respective intended profile depth TP ( Fig. 2 ), which is usually 6.5 mm to 10.0 mm for passenger cars, vans or light trucks, and has on the tread periphery a groove edge 2a on the outside of the tread formed on the shoulder-side profile rib 1 and a groove edge 2b on the inside of the tread, wherein the groove edges 2a, 2b run straight in plan view.

[0027] The shoulder-side tread rib 1 has an outer rib surface 1a located on the tread periphery and is provided with a plurality of transverse grooves 3 which, in plan view, preferably run parallel to one another. The transverse grooves 3 run completely within the shoulder-side tread rib 1, extend beyond the lateral edge of the ground contact patch (line 1), end on the tread inside in front of the groove edge 2a of the shoulder-side circumferential groove 2 on the outside of the tread at a distance a 1 of 2.0 mm to 10.0 mm, in particular of at least 5.0 mm, determined on the rib outer surface 1a in the axial direction, and each have two transverse groove edges 4, 5 on the rib outer surface 1a which, in plan view, are straight, run parallel to one another and to the axial direction, and extend beyond the lateral edge of the ground contact patch (line 1). The transverse groove edge 4 has an edge end section 4a projecting beyond the transverse groove edge 5 on the inside of the tread.Transverse grooves 3 which are immediately consecutive in the circumferential direction are formed - based on the transverse groove edges 4, 5 which are closest to one another - at mutual distances a 2 of preferably 15.0 mm to 35.0 mm, determined in the circumferential direction.

[0028] The further design of the transverse grooves 3 is explained below using a single transverse groove 3.

[0029] According to Fig. 3 the transverse groove 3 has a width b QR of 2.3 mm to 7.0 mm, determined between and perpendicular to the transverse groove edges 4, 5, and furthermore - in each case within the ground contact area - a maximum depth t QR determined in the radial direction ( Fig. 4 ) from 70% to 100% of the tread depth TP ( Fig. 2 ) and a length l QR determined on the outer surface 1a of the rib and projected in the axial direction, which results from the respectively selected distance a 1 ( Fig. 1 ) results.

[0030] The transverse groove 3 is delimited by a transverse groove base 6, a transverse groove flank 8 extending from the transverse groove edge 5, a transverse groove flank 7, a chamfer 7a attached to the transverse groove flank 7 and extending to the transverse groove edge 4, and by an end flank 9 located at the groove end on the inside of the tread, and in the embodiment shown has a groove outlet 3a formed as a shallow depression completely outside the ground contact area (cf. Fig. 6 , Position of section line VI-VI see Fig. 3 ) at which the transverse groove flanks 7, 8 end in the embodiment shown (in Fig. 3 not or hardly recognizable). The transverse groove base 6 extends over the entire transverse groove 3, is therefore continued in the groove outlet 3a, and is, viewed in cross-section perpendicular to the transverse groove edges 4, 5, U-shaped and rounded ( Fig. 4, Fig. 5 ).

[0031] How Fig. 4 und Fig. 5 show, the transverse groove flanks 7, 8, viewed in the cross-section of the transverse groove 3, run at an angle α (transverse groove flank 7), β (transverse groove flank 8) of 0° to 5°, in particular of up to 3°, to the radial direction. The chamfer 7a is an inclined surface which - viewed in cross-section perpendicular to the transverse groove edge 4 - appears as a straight line, wherein the chamfer 7a runs at a constant angle γ of 35° to 55°, in particular of 40° to 50°, to the radial direction, adjoins the transverse groove flank 7 at a constant depth t F determined in the radial direction of 0.5 mm to 2.0 mm, in particular of 1.0 mm to 1.5 mm, a chamfer edge 7a' running at the depth t F (see also Fig. 10 ) and ends in the groove outlet 3a ( Fig. 3 ).

[0032] How Fig. 3 shows, the end flank 9 connects to the inside end of the transverse groove flank 8, is a curved surface (cf. Fig. 10 ) and has on the rib outer surface 1a a boundary edge 9a which is curved in plan view and which continuously (kink-free, "tangential") adjoins the tread-inside end of the transverse groove edge 5 and which projects beyond the edge end section 4a of the transverse groove edge 4 in the axial direction on the tread-inside.

[0033] According to Fig. 1 adjoins the inside tread end of each transverse groove 3 via the transverse groove flank 7, opposite the curved end flank 9, an additional groove 10 which ends within the shoulder-side profile rib 1 and is elongated in plan view (cf. Fig. 3 ), whereby all additional grooves 10 in the embodiment shown run parallel to one another in plan view.

[0034] The further design of the additional grooves 10 is then explained using a single additional groove 10.

[0035] According to Fig. 7 the additional groove 10 has a groove center line m ZR which is aligned in its direction of extension in plan view, the additional groove 10 being straight in plan view and - based on the groove center line m ZR - running at an angle δ of up to ± 35°, in particular of up to ± 25°, preferably of ± 10° to ± 20°, to the circumferential direction and in the exemplary embodiment shown being inclined in such a way that its groove end lying on the transverse groove 3 - compared to its other groove end - is closer to the lateral edge of the ground contact surface (line 1, cf. Fig. 3 ) is located.

[0036] The additional groove 10 has - in each case on the rib outer surface 1a - a groove edge 11a on the inside of the tread and a groove edge 11b on the outside of the tread, wherein the groove edges 11a, 11b run straight, parallel to one another and at the mentioned angle δ in plan view, wherein the groove edge 11a on the inside of the tread continuously adjoins the boundary edge 9a of the end flank 9 and the groove edge 11b on the outside of the tread ends at a distance determined in the circumferential direction in front of the edge end section 4a of the transverse groove edge 4.The additional groove 10 has - in each case determined at the level of the rib outer surface 1a - a length l ZR projected in the circumferential direction relative to the groove center line m ZR of 10.0 mm to 25.0 mm, in particular of 15.0 mm to 20.0 mm, and a constant width b ZR measured perpendicular to the groove center line m ZR between the groove edges 11a, 11b of 0.5 mm to 4.0 mm, preferably of 1.0 mm to 3.5 mm, particularly preferably of 1.5 mm to 3.0 mm.

[0037] According to Fig. 8 is the additional groove 10 - in each case viewed in cross-section perpendicular to the groove center line m ZR (cf. position of the section line VIII-VIII in Fig. 7 ) - U-shaped and defined by a groove flank 12a on the inside of the tread adjacent to the groove edge 11a on the inside of the tread, a groove flank 12b on the outside of the tread adjacent to the groove edge 11b on the outside of the tread, and a groove base 12c extending between the groove flanks 12a, 12b. According to Fig. 10 the transverse groove flank 7 is continued radially within the opening of the additional groove 10 so that it meets the curved end flank 9.

[0038] How Fig. 8 Furthermore, the groove flank 12a on the inside of the tread and the groove flank 12b on the outside of the tread, viewed in cross-section perpendicular to the groove centerline m ZR, each extend at an angle η of 0° to 5°, in particular up to 3°, to the radial direction. The groove flank 12a on the inside of the tread connects - analogously to the corresponding groove edge 11a on the inside of the tread - continuously ("kink-free", "edge-free") to the end flank 9 ( Fig. 7 , Fig. 10 ).

[0039] The groove base 12c of the additional groove 10 has a U-shaped rounded mouth edge 12c' on the transverse groove flank 7 ( Fig. 10 ) and is - like Fig. 9 shows - viewed in the longitudinal section aligned along the groove center line m ZR (cf. position of section line IX-IX in Fig. 7 ), inclined relative to the outer rib surface 1a at a constant angle ε such that the additional groove 10 in the region of the groove base 12c has a depth t ZR which is determined in the radial direction and which continuously increases in the direction of the transverse groove 3, and therefore in the direction of the mouth edge 12c', and which has a value t ZR,MAX of 2.0 mm to 4.0 mm, in particular of 2.5 mm to 3.5 mm, at the mouth edge 12c' and a value t ZR,MIN of up to 1.0 mm, in particular of 0.5 mm to 1.0 mm, at the shallowest point of the additional groove 12. In the embodiment shown, the additional groove 10 has, at its end facing away from the transverse groove 3, an end flank 12d which - viewed in the longitudinal section aligned along the center line m ZR - runs in the shape of a circular arc, continuously adjoins the groove base 12c at the depth t ZR,MIN and which - as Fig. 7 shows - has a boundary edge 12d' on the outer rib surface 1a, which runs in a circular arc and continuously adjoins the groove edges 11a, 11b. Alternatively, the additional groove 10 can run out together with the groove base 12c at its groove end facing away from the transverse groove 3 on the outer rib surface 1a, so that no end flank 12d is provided and the depth t ZR,MIN ( Fig. 9 ) is therefore not present or is 0.0 mm.

[0040] How Fig. 10 and Fig. 11 in combination with each other, is at the transverse groove 3 ( Fig. 10 ) opening of the additional groove 10 between the chamfer 7a formed on the transverse groove flank 7 and the groove flank 12b on the outside of the tread of the additional groove 10 ( Fig. 11 ) extending, continuously outwardly curved corner surface 13, wherein the corner surface 13 is continuously connected to the chamfer 7a as well as to the groove flank 12b on the outside of the tread ( Fig. 11 ) (mutual connecting areas indicated by dashed lines). The term "continuously curved" means that the corner surface 13 is free of flat surface areas and is free of edges or kinks on the inside. The term "outwardly curved" means that the corner surface is dome-shaped and therefore defines or forms a rounded portion (fillet) – and not an indentation.

[0041] Fig. 11 shows a section in the area of ​​the corner surface 13 according to the Fig. 7 radially oriented cutting plane marked by the line XI-XI. This cutting plane runs perpendicular to the groove center line m ZR of the additional groove 10 in plan view. Fig. 11 for the cutting plane marked by the line XI-XI, the corner surface 13 - viewed in each cutting plane oriented in the radial direction and running in plan view perpendicular to the groove center line m ZR of the additional groove 10 - runs in an arcuate manner.

[0042] Fig. 12 shows a section in the area of ​​the corner surface 13 according to the Fig. 7 radially oriented cutting plane marked by the line XII-XII. This cutting plane runs parallel to the groove center line m ZR of the additional groove 10 in plan view. Fig. 12 for the cutting plane marked by the line XII-XII, the corner surface 13 appears as a straight line when viewed in any cutting plane oriented in the radial direction and running parallel to the groove center line m ZR of the additional groove 10 in plan view.

[0043] According to Fig. 10 The corner surface 13 has a radially outer boundary edge 13a on the rib outer surface 1a and a radially inner boundary edge 13b on the transverse groove flank 7. As Fig. 7 shows, the radially outer boundary edge 13a runs in a circular arc in plan view, adjoins both the transverse groove edge 4, i.e. the edge end section 4a, and the groove edge 11b on the outside of the tread of the additional groove 10. Furthermore, the radially outer boundary edge 13a has a length l 1 projected in the axial direction of 1.0 mm to 3.0 mm and a length l 2 projected in the circumferential direction of 1.0 mm to 3.0 mm. According to Fig. 10 the radially inner boundary edge 13b continuously adjoins the chamfer edge 7a', runs arcuately radially inwards from the chamfer edge 7a' and continuously adjoins the mouth edge 12c' of the groove base 12c of the additional groove 10.

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

[0045] The transverse grooves 3 run - based on a groove centerline running centrally between the transverse groove edges 4, 5 in plan view - in particular at an angle of 0° to 25° to the axial direction. The end flank 9 of the transverse grooves 3 can also be designed in a conventional manner and therefore does not have to be curved. The chamfer 7a does not have to extend beyond the ground contact surface, but preferably extends from the curved corner surface 13 at least to the lateral edge of the ground contact surface. In addition to the described transverse grooves 3, into which the additional grooves 10 open, further transverse grooves can be provided in the shoulder-side tread rib 1. The additional grooves 10 can also run curved in plan view, wherein in such additional grooves 10 the aforementioned angle δ refers to a straight line connecting the ends of the curved groove centerline m ZR. The depth t ZR of the additional groove 10 can be constant. List of reference symbols

[0046] 1 Shoulder-side profile rib 1a Rib outer surface 2 Shoulder-side circumferential groove 2al Tread outer groove edge 2b Tread inner groove edge 3 Transverse groove 3a Groove outlet 4 Transverse groove edge 4a Edge end section 5 Transverse groove edge 6 Transverse groove base 7 Transverse groove flank 7a Chamfer 7a' Chamfer edge 8 Transverse groove flank 9 End flank 9a Boundary edge 10 Additional groove 11al Tread inner groove edge 11b Tread outer groove edge 12al Tread inner groove flank 12b Tread outer groove flank 12c Groove base 12c' Mouth edge 12d End flank 12d' Boundary edge 13 Curved corner surface 13a Radial outer boundary edge 13bradial inner boundary edge a 1 , a 2 distance b QR , b ZR width l line (lateral edge of the ground contact patch) l 1 , l 2 projected length I QR , I ZR length m ZR groove center line t F , t ZR depth t QR maximum depth t ZR, MAX, t ZR, MIN value TP tread depth S 10 arrow Z 3 , Z 7 detail α, β, γ, δ, ε, η angle

Claims

1. Pneumatic vehicle tyre with a tread having at least one shoulder-side profile rib (1) which is delimited by a circumferential channel (2) and which has transverse channels (3), said transverse channels ending in front of the circumferential channel (2) and having transverse-channel flanks (7, 8) and transverse-channel edges (4, 5), wherein the tread-inner-side end of each transverse channel (3) is adjoined by a respective additional channel (10) which ends within the shoulder-side profile rib (1), which extends in plan view at an angle (δ) of up to / down to ± 35° to the circumferential direction, and which has a tread-inner-side channel flank (12a) ending at a tread-inner-side channel edge (11a) and has a tread-outer-side channel flank (12b) ending at a tread-outer-side channel edge (11b) and has a channel base (12c) with an opening-out edge (12c') at the transverse channel (3), characterized in that, at at least one transverse-channel flank (7) of each transverse channel (3), the transverse-channel flank (7) is adjoined by a bevel (7a) with a bevel edge (7a'), said bevel extending to the transverse-channel edge (4) and forming an inclined surface, wherein, at the inlet of the additional channel (10), there is formed an outwardly curved corner surface (13) which extends between the tread-outer-side channel flank (12b) of said additional channel and the bevel (7a) adjoining the transverse-channel flank (7) and which has a radially outer delimitation edge (13a), extending between the tread-outer-side channel edge (11b) of the additional channel (10) and the transverse-channel edge (4) to which the bevel (7a) extends, on the rib outer surface (1a) and has a radially inner delimitation edge (13b), extending to the bevel edge (7a'), on the transverse-channel flank (7) adjoined by the bevel (7a), wherein the corner surface (13) is curved in such a way that its radially outer delimitation edge (13a) extends arcuately in plan view and its radially inner delimitation edge (13b), proceeding from the bevel edge (7a'), extends arcuately radially inwards and towards the opening-out edge (12c') of the channel base (12c) towards the additional channel (10).

2. Pneumatic vehicle tyre according to Claim 1, characterized in that, in plan view, the additional channel (10) is inclined in such a way that its channel end situated at the transverse channel (3) - in comparison with its other channel end - is closer to the lateral periphery of the ground contact area (line l).

3. Pneumatic vehicle tyre according to Claim 1 or 2, characterized in that the radially outer delimitation edge (13a) of the corner surface (13) has a first length (l1), projected into the axial direction, of 1.0 mm to 3.0 mm and has a second length (l2), projected into the circumferential direction, of 1.0 mm to 3.0 mm.

4. Pneumatic vehicle tyre according to one of Claims 1 to 3, characterized in that the corner surface (13) continuously adjoins both the bevel (7a) adjoining the transverse-channel flank (7) and the tread-outer-side channel flank (12b) of the additional channel (10), and in that the radially outer delimitation edge (13a) of the corner surface (13) continuously adjoins both the transverse-channel edge (4) to which the bevel (7a) extends and the tread-outer-side channel edge (11b) of the additional channel (10).

5. Pneumatic vehicle tyre according to one of Claims 1 to 4, characterized in that the bevel edge (7a') of the bevel (7a) adjoining the transverse-channel flank (7) extends at a constant depth (tF), determined in a radial direction, of 0.5 mm to 2.0 mm, in particular of 1.0 mm to 1.5 mm.

6. Pneumatic vehicle tyre according to one of Claims 1 to 5, characterized in that the additional channel (10) - in each case at the level of the rib outer surface (1a) - has a length (lZR), based on its channel midline (mZR) and projected into the circumferential direction, of 10.0 mm to 25.0 mm, in particular of 15.0 mm to 20.0 mm, and / or has an in particular constant width (bZR), measured perpendicularly to its channel midline (mZR), of 0.5 mm to 4.0 mm, in particular of 1.0 mm to 3.5 mm, particularly preferably of 1.5 mm to 3.0 mm.

7. Pneumatic vehicle tyre according to one of Claims 1 to 6, characterized in that, in the region of the channel base (12c), the additional channel (10) has a depth (tZR), determined in the radial direction, which increases in the direction of the opening-out edge (12c') of the channel base (12c) and which has a value (tZR, MAX) at the opening-out edge (12c') of 2.0 mm to 4.0 mm, in particular of 2.5 mm to 3.5 mm.

8. Pneumatic vehicle tyre according to Claim 7, characterized in that the depth (tZR) of the additional channel (10) in the region of the channel base (12c) has at the shallowest point of the additional channel (10) a value (tZR, MIN) of up to 1.0 mm, in particular of 0.5 mm to 1.0 mm, or in that the additional channel (10), along with its channel base (12c), runs out at its channel end remote from the transverse channel (3) to the rib outer surface (1a).

9. Pneumatic vehicle tyre according to one of Claims 1 to 8, characterized in that the angle (δ) at which the additional channel (10) extends to the circumferential direction is up to / down to ± 25°, in particular of ± 10° to ± 20°.

10. Pneumatic vehicle tyre according to one of Claims 1 to 9, characterized in that the additional channel (10) extends rectilinearly in plan view.

11. Pneumatic vehicle tyre according to Claim 10, characterized in that the corner surface (13), viewed in any radially oriented section plane extending perpendicularly to the channel midline (mZR) of the additional channel (10) in plan view, extends arcuately, and / or in that the corner surface (13), viewed in any radially oriented section plane extending parallel to the channel midline (mZR) of the additional channel (10) in plan view, appears as a straight line.

12. Pneumatic vehicle tyre according to one of Claims 1 to 11, characterized in that, at its tread-inner-side end, the transverse channel (3) has a curved end flank (9) which extends between the tread-inner-side channel flank (12a) of the additional channel (10) and the transverse-channel flank (8) situated opposite the corner surface (13), which continuously adjoins the transverse-channel flank (8) and the tread-inner-side channel flank (12) of the additional channel (10), and which has on the rib outer surface (1a) an arcuately extending delimitation edge (9a) which continuously adjoins the tread-inner-side channel edge (11a) of the additional channel (10) and the corresponding transverse-channel edge (5).

13. Pneumatic vehicle tyre according to one of Claims 1 to 12, characterized in that the bevel (7a) adjoining the transverse-channel flank (7), viewed in a cross section perpendicular to the associated transverse-channel edge (4), extends at an angle (γ) of 35° to 55°, in particular of 40° to 50°, to the radial direction.

14. Pneumatic vehicle tyre according to one of Claims 1 to 13, characterized in that the bevel (7a) adjoining the transverse-channel flank (7) extends at least up to the lateral periphery (line l) of the ground contact area of the tread.