Vehicle pneumatic tire

Abstract

The invention relates to a vehicle pneumatic tire having a tread with at least one shoulder-side tread rib (1) delimited by circumferential grooves (2), which has transverse grooves (3) ending before the circumferential grooves (2), which have transverse groove flanks (7, 8) and transverse groove edges (4, 5), wherein an additional groove (10) is connected corresponding to the end on the inside of the tread of each transverse groove (3), which ends in the shoulder-side tread rib (1), extends in top view at an angle (delta) of at most + / - 35° to the circumferential direction and has an inside-of-tread groove flank (12a) ending at an inside-of-tread groove edge (11a), an outside-of-tread groove flank (12b) ending at an outside-of-tread groove edge (11b) and a groove bottom (12c) with a run-on edge (12c') at the transverse groove (3). At at least one transverse groove flank (7) of each transverse groove (3), a bevel (7a) extending to the transverse groove edge (4) is formed, which forms an inclined surface, which has a bevel edge (7a') at the transverse groove flank (7), wherein at the run-on of the additional groove (10), an outwardly curved corner surface (13) is designed, which extends between the outside-of-tread groove flank (12b) of the additional groove (10) and the bevel (7a) formed at the transverse groove flank (7), which has a radially outer delimiting edge (13a) on the outer rib surface (1a) extending between the outside-of-tread groove edge (11b) of the additional groove (10) and the transverse groove edge (4) to which the bevel (7a) extends, and has a radially inner delimiting edge (13b) at the transverse groove flank (7) on which the bevel (7a) is formed, which extends to the bevel edge (7a'), wherein the corner surface (13) is curved such that its radially outer delimiting edge (13a) extends in top view arched and its radially inner delimiting edge (13b) extends from the bevel edge (7a') arched radially inwards and towards the run-on edge (12c') of the groove bottom (12c) to the additional groove (10).

Description

Technical Field

[0001] The present invention relates to a pneumatic tire for a vehicle having a tread having at least one shoulder-side tread rib defined by circumferential grooves, the at least one shoulder-side tread rib having lateral grooves terminating before the circumferential grooves, the lateral grooves having lateral groove sides and lateral groove edges, wherein an additional groove is correspondingly connected to the end of each lateral groove on the inner side of the tread, the additional groove terminating within the shoulder-side tread rib, extending at an angle of up to ±35° with the circumferential direction in a top view, and having inner tread groove sides terminating at the groove edges on the inner side of the tread, outer tread groove sides terminating at the groove edges on the outer side of the tread, and a groove bottom having a confluence edge located at the lateral groove. Background Technology

[0002] Such pneumatic tires for vehicles are known, for example, from DE 10 2014 225 621 A1. A pneumatic tire for a vehicle has a tread with at least one shoulder-side tread rib defined by circumferential grooves. This at least one shoulder-side tread rib has lateral grooves terminating before the circumferential grooves, wherein additional grooves extending at an angle of up to ±10° with the circumferential direction merge at the inner end of the lateral grooves on the tread side. These additional grooves have a depth of at least 1.5 mm to 3.0 mm and a width increasing toward the lateral grooves over a substantial portion of their radial extension. The additional grooves improve the water drainage capacity of the tread ribs without affecting the stiffness of the shoulder-side tread ribs.

[0003] Furthermore, it is known that pneumatic tires for vehicles have treads with shoulder-side ribs and lateral grooves, wherein chamfers extending toward the edges of the lateral grooves are formed on the sides of the lateral grooves, which is particularly advantageous for braking performance on dry roads. Such tires are disclosed, for example, in DE 10 2015 202 614A1.

[0004] It is known that when designing tire tread patterns, there are often conflicting objectives, namely, improving tire performance at the expense of other tire performance characteristics. One such conflict is the conflict between dry performance and wet performance. Summary of the Invention

[0005] The purpose of this invention is to improve dry and wet performance to the same extent possible in vehicle pneumatic tires of the type described at the outset, thereby resolving the corresponding objective conflict at a higher level of technology than before.

[0006] According to the present invention, the proposed objective is achieved in the following manner: a chamfer extending to the edge of the lateral groove and forming an inclined surface is formed at at least one lateral groove side of each lateral groove, the chamfer having a chamfer edge located at the lateral groove side, wherein an outwardly curved corner face is designed at the confluence of the additional groove, extending between the groove side on the outer side of its tread and the chamfer formed at the lateral groove side, the corner face having a radially outer fixed edge extending between the groove edge on the outer side of the additional groove and the lateral groove edge to which the chamfer extends on the outer surface of the rib, and having a radially inner defining edge extending to the chamfer edge at the lateral groove side on which the chamfer is formed, wherein the corner face is curved such that its radially outer fixed edge extends arcuately in a top view, and its radially inner defining edge extends radially inward arcuately from the chamfer edge and extends toward the confluence edge of the groove bottom to the additional groove.

[0007] Therefore, according to the present invention, the known scheme of chamfering at the transverse grooves is integrated in a special way into a vehicle pneumatic tire of the type described at the outset and extended by a specially designed outwardly curved corner facet. The chamfering is particularly advantageous for dry performance. The curved corner facet allows for particularly low turbulence of water flow from the additional grooves to the transverse grooves, and locally enlarges its cross-section in the confluence area of ​​the additional grooves, which is beneficial to the water absorption of the transverse grooves. Furthermore, the curved corner facet rounds off the corner regions present at the groove intersections, thereby effectively counteracting the curling of the groove edges located there. Thus, both dry and wet performance are improved, and the corresponding conflicting objectives are resolved at a higher level of technology.

[0008] According to a preferred embodiment, the additional grooves are angled in a top view such that the end of the groove located at the transverse groove is closer to the lateral outer edge of the ground contact surface than the other end of its groove. This facilitates water flow towards the lateral outer edge of the ground contact surface and thus further benefits wetland performance.

[0009] According to another preferred embodiment, the radially outer fixed edge of the corner face has a first length of 1.0 mm to 3.0 mm projected along the axial direction and a second length of 1.0 mm to 3.0 mm projected along the circumferential direction. Therefore, the corner face is implemented to be relatively small, thus having almost no impact on the net contact area of ​​the tread, which is beneficial for dry ground performance.

[0010] When the corner face is continuously connected to both the chamfer formed on the side of the transverse groove and the groove side of the outer side of the additional groove, and when the radial outer edge of the corner face is continuously connected to both the edge of the transverse groove to which the chamfer extends and the groove edge of the outer side of the additional groove, the water flow from the additional groove to the transverse groove is further improved in terms of local drainage characteristics.

[0011] Another preferred embodiment is characterized in that the chamfered edge formed on the side of the transverse groove extends to a constant depth of 0.5 mm to 2.0 mm, particularly 1.0 mm to 1.5 mm, measured in the radial direction. This type of chamfering is advantageous for dry ground performance.

[0012] According to another preferred embodiment, the additional grooves accordingly have a length of 10.0 mm to 25.0 mm, particularly 15.0 mm to 20.0 mm, projected circumferentially about their centerline on the horizontal surface of the outer surface of the rib, and / or have a particularly constant width of 0.5 mm to 4.0 mm, particularly 1.0 mm to 3.5 mm, especially preferably 1.5 mm to 3.0 mm, measured perpendicular to their centerline. This design of the additional grooves provides high water absorption, which is beneficial for wet performance. Compared to common lateral grooves, the net contact area of ​​the tread is almost not reduced, which is beneficial for dry performance.

[0013] According to another preferred embodiment, the additional groove has a depth, measured radially and increasing toward the confluence edge of the groove bottom, in the region of the groove bottom. This depth has a value of 2.0 mm to 4.0 mm, particularly 2.5 mm to 3.5 mm, at the confluence edge. The increased depth toward the transverse grooves facilitates drainage from the additional groove to the transverse groove, wherein, since the depth of the additional groove is not too large, its effect on the stiffness of the tread ribs is particularly small, which in turn is beneficial to dry ground performance.

[0014] In the previous embodiment, it is advantageous that, in the region of the groove bottom, the depth of the additional groove has a value of up to 1.0 mm, particularly 0.5 mm to 1.0 mm, at the shallowest part of the additional groove, or the additional groove, together with its groove bottom, extends to the outer surface of the rib at its groove end opposite to the transverse groove. This enhances the aforementioned technical effect.

[0015] According to another preferred embodiment, the additional grooves extend at an angle of up to ±25°, particularly ±10° to ±20°, relative to the circumferential direction. This further facilitates drainage from the additional grooves to the transverse grooves.

[0016] According to another preferred embodiment, the additional grooves extend in a straight line in the top view, which also facilitates drainage from the additional grooves to the transverse grooves.

[0017] In the preferred embodiment above, a preferred variation is that: when viewed in each cross-sectional plane oriented radially and extending perpendicularly to the center line of the additional groove in the top view, the corner face extends arcuately; and / or when viewed in each cross-sectional plane oriented radially and extending parallel to the center line of the additional groove in the top view, the corner face appears to be straight.

[0018] Another preferred embodiment is characterized in that: the lateral grooves have, at their inner ends on the tread side, an arcuate end face extending between the groove side of the additional groove on the inner tread side and the lateral groove side opposite to the corner face, the arcuate end face continuously adjoining the lateral groove side and the groove side of the additional groove on the inner tread side, and the arcuate end face having an arcuately extending defining edge on the outer surface of the rib, the defining edge continuously adjoining the groove edge of the additional groove on the inner tread side and the corresponding lateral groove edge. Regarding the low turbulence of the water flow from the additional grooves to the lateral grooves, the arcuate end face works in a particularly advantageous manner with respect to the additional grooves and the curved corner face, and thus contributes to further improvement of wetland performance.

[0019] According to another preferred embodiment, when viewed in a cross-section perpendicular to the edge of the relevant transverse groove, the chamfer formed on the side of the transverse groove extends at an angle of 35° to 55°, particularly 40° to 50°, to the radial direction. Such a chamfer effectively counteracts the "curling" of the corresponding transverse groove edge, thus improving dry performance.

[0020] Furthermore, which is beneficial for dry performance, the chamfer formed on the side of the lateral grooves extends at least to the lateral outer edge of the tread's contact surface with the ground. Attached Figure Description

[0021] Other features, advantages, and details of the invention will now be explained in detail with the aid of the accompanying drawings, which schematically illustrate embodiments of the invention. In the drawings:

[0022] Figure 1 A top view showing a circumferential section of the shoulder side region of the tread of a vehicle pneumatic tire having an embodiment of the present invention is shown.

[0023] Figure 2 Show along Figure 1 The cross section of line II-II in the middle,

[0024] Figure 3 Show Figure 1 A magnified top view of the details of Z3.

[0025] Figure 4 Show along Figure 3 The cross section of line IV-IV in the middle,

[0026] Figure 5 Show along Figure 3 The cross section of line VV in the middle,

[0027] Figure 6 Show along Figure 3 The cross section of line VI-VI in the middle,

[0028] Figure 7 Show Figure 3 Another enlarged top view of the Z7 in detail.

[0029] Figure 8 Show along Figure 7 The cross section of line VIII-VIII in the middle,

[0030] Figure 9 Show along Figure 7 The cross section of line IX-IX in the middle.

[0031] Figure 10 Showing according to Figure 7 Arrow S in the middle 10 A magnified view indicating the direction of the line of sight.

[0032] Figure 11 Show along Figure 7 Enlarged cross-sectional view of line XI-XI, and

[0033] Figure 12 Show along Figure 7 Enlarged cross-sectional view of line XII-XII.

[0034] List of reference numerals

[0035] 1..............Tread ribs on the shoulder side of the tire

[0036] 1a.............Outer surface of the rib

[0037] 2. Circular grooves on the shoulder side of the tire

[0038] 2a.............The edge of the groove on the outer side of the tread

[0039] 2b.............Edge of the grooves on the inner side of the tread

[0040] 3.............. Horizontal grooves

[0041] 3a.............groove rollout section

[0042] 4..............Horizontal groove edge

[0043] 4a.............Edge end section

[0044] 5..............Horizontal groove edge

[0045] 6..............Horizontal groove bottom

[0046] 7.............. Horizontal groove side

[0047] 7a.............Beveling

[0048] 7a'............Beveled edge

[0049] 8.............. Horizontal groove side

[0050] 9..............End side

[0051] 9a.............define the edge

[0052] 10.............Additional grooves

[0053] 11a............Edge of the grooves on the inner side of the tread

[0054] 11b............Edge of the grooves on the outer side of the tread

[0055] 12a............The inner groove side of the tire tread

[0056] 12b............The outer groove side of the tread

[0057] 12c............grooved bottom

[0058] 12c'...........merging into the edge

[0059] 12d............End side

[0060] 12d'...........defines the edge

[0061] 13.............Curved corner face

[0062] 13a............Radial outer edge

[0063] 13b............Radial inner boundary

[0064] a1, a2... spacing

[0065] b QR b ZR .........width

[0066] l..............line (lateral outer edge of the ground contact surface)

[0067] l1, l2..........projection length

[0068] l QR , l ZR .........length

[0069] m ZR ... Center line of grooves

[0070] t F , t ZR .........depth

[0071] t QR Maximum depth

[0072] t ZR,MAX , t ZR,MIN .....value

[0073] T P ...Tread depth

[0074] S 10 .............arrow

[0075] Z3, Z7..........details

[0076] α, β, γ, δ, ε, eta angles Detailed Implementation

[0077] The pneumatic tires of the present invention are tires for motor vehicles, especially for multi-track motor vehicles, and preferably radial tires for passenger vehicles, trucks or light trucks (light trucks with a permissible gross weight ≤ 7.5t).

[0078] Figure 1 A top view shows a circumferential section of the tread of a pneumatic tire, extending circumferentially around the shoulder side, defined by circumferential grooves 2 on the shoulder side. The lateral outer edge of the ground contact surface (measured according to ETRTO standards by measuring a tire mounted on a standard rim with a load of 70% of maximum load capacity and an internal pressure of 85% of standard pressure) is marked by a dashed line 1. Areas of the tread not shown can be designed in known ways.

[0079] In the illustrated embodiment, the circumferential groove 2 on the shoulder side extends in a straight line in the top view, with a correspondingly set tread depth T in the radial direction. P ( Figure 2The tread depth is typically 6.5 mm to 10.0 mm for passenger cars, vans or light trucks, and the circumferential grooves on the shoulder side have groove edges 2a on the outer side of the tread and groove edges 2b on the inner side of the tread formed on the tread ribs 1 on the shoulder side, wherein the groove edges 2a and 2b extend in a straight line in a top view.

[0080] The tread rib 1 on the shoulder side has an outer surface 1a located on the periphery of the tread and is provided with a plurality of lateral grooves 3 that preferably extend parallel to each other in a top view. The lateral grooves 3 extend entirely within the tread rib 1 on the shoulder side, extending past the lateral outer edge (line l) of the ground contact surface, and terminate at a distance a1 of 2.0 mm to 10.0 mm, particularly at least 5.0 mm, measured axially on the outer surface 1a before the groove edge 2a of the circumferential groove 2 on the shoulder side. These lateral grooves respectively have two lateral groove edges 4, 5 on the outer surface 1a that are straight, parallel to each other, and extend axially past the lateral outer edge (line l) of the ground contact surface in a top view. The lateral groove edge 4 has an edge end section 4a that extends beyond the lateral groove edge 5 on the inner side of the tread. Referring to the nearest transverse groove edges 4 and 5, transverse grooves 3 are formed directly and successively in the circumferential direction with a mutual spacing a2 of preferably 15.0 mm to 35.0 mm as measured in the circumferential direction.

[0081] The following section will use the individual horizontal groove 3 to illustrate another design scheme for the horizontal groove 3.

[0082] according to Figure 3 The transverse grooves 3 have a width b between 2.3 mm and 7.0 mm, measured perpendicularly to the edges of the transverse grooves 4 and 5. QR Furthermore, it also possesses a maximum depth t measured in the radial direction within the ground contact surface. QR ( Figure 4 The maximum depth is the tread depth T. P ( Figure 2 70% to 100% of; and the length l projected along the axial direction on the outer surface 1a of the rib. QR The length is correspondingly determined by the selected spacing a1( Figure 1 (This is the conclusion.)

[0083] The lateral groove 3 is defined by the lateral groove base 6, the lateral groove side surface 8 extending from the lateral groove edge 5, the lateral groove side surface 7, the chamfer 7a formed at the lateral groove side surface 7 and extending to the lateral groove edge 4, and the end side surface 9 of the groove end located inside the tread. In the illustrated embodiment, the lateral groove has a shallowly recessed groove roll-out portion 3a completely outside the ground contact surface (see reference). Figure 6See Figure 3 (the position of section line VI-VI), in the illustrated embodiment, the transverse groove sides 7 and 8 terminate at the groove rollout portion (at... Figure 3 (Invisible or almost invisible). The transverse groove bottom 6 extends over the entire transverse groove 3, thus continuing in the groove rollout 3a, and is implemented as a U-shaped rounding when viewed in a section perpendicular to the transverse groove edges 4, 5. Figure 4 , Figure 5 ).

[0084] like Figure 4 and Figure 5 As shown, when viewed in a cross-section of the transverse groove 3, the transverse groove sides 7 and 8 extend at angles α (transverse groove side 7) and β (transverse groove side 8) to the radial direction, respectively, from 0° to 5°, and particularly from 3°. The chamfer 7a is an inclined surface, which appears as a straight line when viewed in a cross-section perpendicular to the transverse groove edge 4. The chamfer 7a extends at a constant angle γ to the radial direction from 35° to 55°, and particularly from 40° to 50°, to a constant depth t measured in the radial direction from 0.5 mm to 2.0 mm, and particularly from 1.0 mm to 1.5 mm. F Connected to the transverse groove side 7, the chamfer has a depth t F Extended chamfered edge 7a' (see also) Figure 10 And the extension terminates in the grooved rollout portion 3a. Figure 3 ).

[0085] like Figure 3 As shown, the end face 9 is connected to the end of the inner side of the tread of the transverse groove side 8, and is a curved surface (see reference). Figure 10 Furthermore, the end face has a defining edge 9a extending arcuately in top view on the outer surface 1a of the rib, which is continuously (without inflection, "tangentially") connected to the end of the tread inner side of the transverse groove edge 5, and the defining edge extends axially beyond the edge end section 4a of the transverse groove edge 4 on the tread inner side.

[0086] according to Figure 1 On the lateral groove side 7, corresponding to the inner end of each lateral groove 3 on the tread side, opposite to the arcuate end side 9, there is an additional groove 10 that terminates within the tread rib 1 on the shoulder side and extends elongated in the top view (see [reference]). Figure 3 In the illustrated embodiment, all additional grooves 10 extend parallel to each other in the top view.

[0087] The following describes another implementation of the additional groove 10 using the separate additional groove 10.

[0088] according to Figure 7The additional groove 10 has a groove centerline m oriented along its extension direction in the top view. ZR The additional groove 10 extends in a straight line in the top view, and is referenced to the groove centerline m. ZR Extending at an angle δ of up to ±35°, particularly ±25°, preferably ±10° to ±20° with respect to the circumferential direction, and in the illustrated embodiment, the additional groove is inclined such that the groove end located at the transverse groove 3 is closer to the lateral outer edge (line 1, reference) of the ground contact surface than the other groove end. Figure 3 ).

[0089] The additional groove 10 has a groove edge 11a on the inner side of the tread and a groove edge 11b on the outer side of the tread on the outer surface 1a of the rib. The groove edges 11a and 11b extend in a straight line, parallel to each other, and at an angle δ as mentioned in the top view. The groove edge 11a on the inner side of the tread is continuously connected to the defining edge 9a of the end face 9, and the groove edge 11b on the outer side of the tread terminates before the edge end section 4a of the lateral groove edge 4 at a spacing measured in the circumferential direction. The additional groove 10 correspondingly has a groove centerline m measured at the level of the outer surface 1a of the rib. ZR The length l projected along the circumferential direction is 10.0 mm to 25.0 mm, especially 15.0 mm to 20.0 mm. ZR and m perpendicular to the center line of the groove ZR A constant width b, measured between the groove edges 11a and 11b, ranging from 0.5 mm to 4.0 mm, preferably from 1.0 mm to 3.5 mm, and particularly preferably from 1.5 mm to 3.0 mm. ZR .

[0090] according to Figure 8 Correspondingly, at m perpendicular to the center line of the groove ZR Cross-sectional observation (reference) Figure 7 (The location of section lines VIII-VIII in the diagram), the additional groove 10 is implemented as a U-shape and is defined by the inner groove side 12a connected to the groove edge 11a on the inner side of the tread, the outer groove side 12b connected to the groove edge 11b on the outer side of the tread, and the groove bottom 12c extending between the groove sides 12a and 12b. According to Figure 10 The transverse groove side 7 continues radially inside the confluence of the additional groove 10, so that the transverse groove side intersects with the curved end side 9.

[0091] like Figure 8 It is also shown that, at a point m perpendicular to the center line of the groove ZRObserved in cross-section, the groove sidewalls 12a on the inner side of the tread and 12b on the outer side of the tread extend at an angle η of 0° to 5°, and especially up to 3°, with respect to the radial direction. Similar to the groove edge 11a on the inner side of the tread, the groove sidewalls 12a on the inner side of the tread are continuously ("without inflection point", "without edge") connected to the end sidewalls 9. Figure 7 , Figure 10 ).

[0092] The groove bottom 12c of the additional groove 10 has a U-shaped rounded confluence edge 12c' on the transverse groove side 7. Figure 10 ), and as Figure 9 As shown, along the center line m of the groove ZR Observation in a directional longitudinal section (reference) Figure 7 (At the position of section line IX-IX in the diagram), the groove bottom is inclined at a constant angle ε relative to the outer surface 1a of the rib, such that the additional groove 10 has a depth t that increases continuously in the region of the groove bottom 12c, measured in the radial direction, toward the transverse groove 3, and therefore toward the confluence edge 12c'. ZR This depth has a value of 2.0 mm to 4.0 mm, particularly 2.5 mm to 3.5 mm, at the confluence edge 12c'. ZR,MAX And at the shallowest part of the additional groove 12, it has a value of up to 1.0 mm, especially 0.5 mm to 1.0 mm. ZR,MIN In the illustrated embodiment, the additional groove 10 has an end face 12d at its groove end opposite to the transverse groove 3, correspondingly along the centerline m ZR Viewed in a directional longitudinal section, the side of this end extends in an arc shape to a depth of t. ZR,MIN It is continuously connected to the grooved bottom 12c, and as... Figure 7 As shown, the end facet has an arcuately extending defining edge 12d' on the outer surface 1a of the rib, continuously connecting with the groove edges 11a, 11b. Alternatively, the additional groove 10 may extend together with the groove bottom 12c at its groove end opposite to the transverse groove 3, terminating at the outer surface 1a of the rib, thus without the end facet 12d and therefore without a depth t. ZR,MIN ( Figure 9 () does not exist or is 0.0mm.

[0093] like Figure 10 and Figure 11 As shown in combination, in the additional groove 10, the transverse groove 3 ( Figure 10 The merging part at the location is designed with a chamfer 7a formed at the lateral groove side 7 and a groove side 12b on the outer side of the tread of the additional groove 10. Figure 11The corner face 13 extends continuously outward between the two sides, wherein the corner face 13 is continuously connected to the chamfer 7a and the groove side surface 12b on the outer side of the tread. Figure 11 ) Continuously connected (the connecting areas are indicated by dashed lines). The expression "continuous curvature" means that corner face 13 has no flat surface area and no edges or bends inside. The expression "outward curvature" means that the corner face is dome-shaped and thus defines or forms a rounded (rounded) portion, rather than a concave portion.

[0094] Figure 11 Showing according to Figure 7 The cross-section of the region of the corner face 13 of the radially oriented cross-section plane indicated by line XI-XI. This cross-section plane is perpendicular to the groove centerline m of the additional groove 10 in the top view. ZR Extension. For example... Figure 11 For the cross-section indicated by line XI-XI, each groove centerline m, oriented radially and perpendicular to the additional groove 10 in the top view, is shown. ZR When viewed in the extended cross-section, corner face 13 extends in an arc shape.

[0095] Figure 12 Showing according to Figure 7 The cross-section of the region of the corner face 13 of the radially oriented cross-section plane marked by line XII-XII. This cross-section plane is parallel to the groove centerline m of the additional groove 10 in the top view. ZR Extension. For example... Figure 12 For the cross-section indicated by line XII-XII, each groove centerline m, oriented radially and parallel to the additional groove 10 in the top view, is shown. ZR When viewed from the extended cross-section, corner 13 appears to be a straight line.

[0096] according to Figure 10 The corner face 13 has a radially outer defining edge 13a on the outer surface 1a of the rib, and a radially inner defining edge 13b on the transverse groove side 7. For example... Figure 7 As shown, the radially outer fixed edge 13a extends in an arc shape in the top view, continuously connecting with both the lateral groove edge 4 (i.e., the edge end section 4a) and the groove edge 11b on the outer side of the tread of the additional groove 10. Furthermore, the radially outer fixed edge 13a has a length l1 of 1.0 mm to 3.0 mm projected along the axial direction and a length l2 of 1.0 mm to 3.0 mm projected along the circumferential direction. Figure 10 The radial inner defining edge 13b is continuously connected to the chamfered edge 7a', which extends radially inward in an arc shape from the chamfered edge 7a' and is continuously connected to the confluence edge 12c' of the groove bottom 12c of the additional groove 10.

[0097] The present invention is not limited to the described embodiments.

[0098] Referring to the centerline of the grooves extending centered between the edges 4 and 5 of the lateral grooves in the top view, the lateral grooves 3 extend at an angle of 0° to 25° with respect to the axial direction. The end facets 9 of the lateral grooves 3 can also be implemented in a conventional manner, and therefore do not necessarily extend in an arc shape. The chamfer 7a does not necessarily extend beyond the ground contact surface, but preferably originates from the curved corner facet 13 and extends at least to the lateral outer edge of the ground contact surface. In addition to the lateral grooves 3 into which the additional grooves 10 described herein merge, additional lateral grooves may also be provided in the tread ribs 1 on the shoulder side. The additional grooves 10 can also extend in an arc shape in the top view, wherein in such additional grooves 10, the mentioned angle δ relates to the centerline m of the groove extending in an arc shape. ZR The straight line connecting the ends. The depth t of the additional groove 10. ZR It can be implemented as constant.

Claims

1. A pneumatic tire for a vehicle having a tread having at least one shoulder-side tread rib (1) defined by a circumferential groove (2), the at least one shoulder-side tread rib having a lateral groove (3) terminating before the circumferential groove (2), the lateral groove having lateral groove sides (7, 8) and lateral groove edges (4, 5), wherein an additional groove (10) is correspondingly connected to the end of the tread inner side of each lateral groove (3), the additional groove terminating within the tread rib (1) on the shoulder side, extending at an angle (δ) of up to ±35° with respect to the circumferential direction in a top view, and having an inner tread groove side (12a) terminating at a groove edge (11a) on the inner side of the tread, an outer tread groove side (12b) terminating at a groove edge (11b) on the outer side of the tread, and a groove bottom (12c) with a confluence edge (12c') located at the lateral groove (3). Its features are, A chamfer (7a) extending to the edge (4) of the transverse groove (3) and forming an inclined surface is formed at at least one transverse groove side (7), the chamfer having a chamfer edge (7a') located at the transverse groove side (7). The additional groove (10) has an outwardly curved corner face (13) at the confluence of the groove side (12b) on the outer side of the tread and a chamfer (7a) formed on the side of the transverse groove (7). The corner face has a radially outer defined edge (13a) on the outer surface (1a) of the rib that extends between the groove edge (11b) on the outer side of the tread of the additional groove (10) and the side of the transverse groove (4) to which the chamfer (7a) extends. It also has a radially inner defined edge (13b) at the side of the transverse groove (7) on which the chamfer (7a) is formed, extending to the chamfer edge (7a'). The corner face (13) is bent such that its radially outer defining edge (13a) extends arcuately in the top view, and its radially inner defining edge (13b) extends arcuately radially inward from the chamfered edge (7a') and toward the confluence edge (12c') of the groove bottom (12c) to the additional groove (10).

2. The vehicle pneumatic tire according to claim 1, characterized in that, The additional groove (10) is tilted in the top view such that the end of the groove located at the transverse groove (3) is closer to the lateral outer edge (line l) of the ground contact surface of the tread than the other end of its groove.

3. The vehicle pneumatic tire according to claim 1, characterized in that, The radially outer fixed edge (13a) of the corner face (13) has a first length (l1) of 1.0 mm to 3.0 mm projected along the axial direction and a second length (l2) of 1.0 mm to 3.0 mm projected along the circumferential direction.

4. The vehicle pneumatic tire according to claim 1, characterized in that, The corner face (13) is continuously connected to the chamfer (7a) formed at the transverse groove side surface (7), and also continuously connected to the groove side surface (12b) on the outer side of the tread of the additional groove (10); and The radial outer edge (13a) of the corner face (13) is continuously connected to the edge (4) of the transverse groove to which the chamfer (7a) extends, and is also continuously connected to the groove edge (11b) on the outer side of the tread of the additional groove (10).

5. The vehicle pneumatic tire according to claim 1, characterized in that, The chamfer edge (7a') of the chamfer (7a) formed at the transverse groove side (7) has a constant depth (t) of 0.5 mm to 2.0 mm measured in the radial direction. F )extend.

6. The vehicle pneumatic tire according to claim 5, characterized in that, The chamfer edge (7a') of the chamfer (7a) formed at the transverse groove side (7) has a constant depth (t) of 1.0 mm to 1.5 mm measured in the radial direction. F )extend.

7. The vehicle pneumatic tire according to claim 1, characterized in that, The additional grooves (10) correspondingly have a groove centerline (m) at the level of the outer surface (1a) of the rib. ZR The length (l) projected along the circumferential direction from 10.0 mm to 25.0 mm. ZR ), and / or The additional grooves have a perpendicularity to their center line (m) ZR Width measured from 0.5 mm to 4.0 mm (b) ZR ).

8. The vehicle pneumatic tire according to claim 7, characterized in that, The additional grooves (10) correspondingly have a groove centerline (m) at the level of the outer surface (1a) of the rib. ZR The length (l) projected along the circumferential direction from 15.0 mm to 20.0 mm. ZR ).

9. The vehicle pneumatic tire according to claim 7, characterized in that, The additional grooves have a perpendicularity to their center line (m) ZR Width measured from 1.0 mm to 3.5 mm (b) ZR ).

10. The vehicle pneumatic tire according to claim 7, characterized in that, The additional grooves have a perpendicularity to their center line (m) ZR Width measured from 1.5 mm to 3.0 mm (b) ZR ).

11. The vehicle pneumatic tire according to any one of claims 7 to 10, characterized in that, The additional grooves have a perpendicularity to their center line (m) ZR ) The constant width measured (b) ZR ).

12. The vehicle pneumatic tire according to claim 1, characterized in that, The additional groove (10) has a depth (t) in the region of the groove bottom (12c) that increases radially toward the confluence edge (12c') of the groove bottom (12c). ZR The depth has a value of 2.0 mm to 4.0 mm at the confluence edge (12c'). ZR,MAX ).

13. The vehicle pneumatic tire according to claim 12, characterized in that, The depth (t) of the additional groove (10) ZR The value of t at the confluence edge (12c') is 2.5 mm to 3.5 mm. ZR,MAX ).

14. The vehicle pneumatic tire according to claim 12, characterized in that, In the region of the grooved bottom (12c), the depth (t) of the additional groove (10) ZR The value (t) at the shallowest part of the additional groove (10) is up to 1.0 mm. ZR,MIN );or The additional groove (10) extends together with its groove bottom (12c) to the outer surface (1a) of the rib at the groove end opposite to the transverse groove (3).

15. The vehicle pneumatic tire according to claim 14, characterized in that, In the region of the grooved bottom (12c), the depth (t) of the additional groove (10) ZR The value of t is 0.5 mm to 1.0 mm at the shallowest part of the additional groove (10). ZR,MIN ).

16. The vehicle pneumatic tire according to claim 1, characterized in that, The additional groove (10) extends at an angle (δ) relative to the circumferential direction to a maximum of ±25°.

17. The vehicle pneumatic tire according to claim 16, characterized in that, The angle (δ) formed by the extension of the additional groove (10) relative to the circumferential direction is ±10° to ±20°.

18. The vehicle pneumatic tire according to claim 1, characterized in that, The additional groove (10) extends in a straight line in the top view.

19. The vehicle pneumatic tire according to claim 18, characterized in that, In each radially oriented groove centerline (m) that is perpendicular to the additional groove (10) in the top view ZR When viewed in the extended cross-sectional plane, the corner facet (13) extends in an arc shape; and / or In each radially oriented groove centerline (m) parallel to the additional groove (10) in the top view ZR When viewed in the extended cross-section, the corner face (13) appears to be a straight line.

20. The vehicle pneumatic tire according to claim 1, characterized in that, The transverse groove (3) has an arcuate end face (9) at its end on the inner side of the tread, extending between the groove side face (12a) on the inner side of the additional groove (10) and the transverse groove side face (8) opposite to the corner face (13). The end face is continuously connected to the transverse groove face (8) and to the groove face (12) on the inner side of the tread of the additional groove (10), and The end face has an arc-shaped defining edge (9a) at the outer surface (1a) of the rib, which is continuously connected to the groove edge (11a) on the inner side of the tread of the additional groove (10) and to the corresponding transverse groove edge (5).

21. The vehicle pneumatic tire according to claim 1, characterized in that, When viewed in a section perpendicular to the edge (4) of the associated transverse groove, the chamfer (7a) formed at the side (7) of the transverse groove extends at an angle (γ) of 35° to 55° with respect to the radial direction.

22. The vehicle pneumatic tire according to claim 21, characterized in that, When viewed in a section perpendicular to the relevant transverse groove edge (4), the chamfer (7a) formed at the transverse groove side (7) extends at an angle (γ) of 40° to 50° with the radial direction.

23. The vehicle pneumatic tire according to claim 1, characterized in that, The chamfer (7a) formed at the side of the transverse groove (7) extends at least to the lateral outer edge (line l) of the ground contact surface of the tread.

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