Vehicle pneumatic tires

Abstract

The invention relates to a vehicle pneumatic tire with a tread having at least one shoulder-side profile block row (1) which has a shoulder section (4) located outside the ground contact area and transverse grooves (7, 8), wherein in the shoulder section (4) adjacent to transverse grooves (8) recesses (14, 15) are formed with a maximum depth (tv) of 0.5 mm to 2.0 mm, a maximum length (cv) of 7.0 mm to 15.0 mm and a maximum width (bv) of 18% to 50% of the maximum length (cv). Each depression (14, 15) is trapezoidal in plan view and has a boundary edge (16a) facing away from the transverse groove (8), forming the shorter base of the trapezoid, which encloses an angle (γ) of 125° to 145° with each boundary edge (16b, 16c) forming a leg of the trapezoid. Alternatively, each depression, viewed from above, is triangular in shape and has two boundary edges extending to the transverse groove (8), which enclose an angle of 110° to 140° with each other.

Description

[0001] The invention relates to a pneumatic vehicle tire with a tread having at least one shoulder-side profile block row, which has an inner section located within the ground contact area, a shoulder section located outside the ground contact area and transverse grooves, wherein in the shoulder section adjacent to transverse grooves along the respective transverse groove over its course elongated depressions with a maximum depth of 0.5 mm to 2.0 mm, a maximum length at the transverse groove of 7.0 mm to 15.0 mm and a maximum width of 18% to 50% of the maximum length are formed.

[0002] Such a pneumatic vehicle tire is known, for example, from DE 10 2019 218 845 A1. The tire has a tread with a shoulder-side tread block row with transverse grooves, wherein in the shoulder section of the tread block row located outside the ground contact area, lens-shaped depressions are formed adjacent to the transverse grooves in each case in plan view. These depressions are elongated in the direction of extension of the transverse grooves, have a maximum depth of 1.0 mm to 3.0 mm, a maximum length of 5.0 mm to 10.0 mm and a maximum width of 20% to 50% of their maximum length. When driving on a snow-covered road surface, snow collects in the depressions and compacts there, so that the steering forces acting on the tire are effectively transferred to the road surface via the effect of snow-snow friction.

[0003] The invention is based on the object of further improving the depressions in a pneumatic vehicle tire of the type mentioned above with regard to their advantageous effects on snow performance, while maintaining a high crack resistance of the rubber material immediately adjacent to the depressions.

[0004] The problem is solved according to the invention by a) that each depression, viewed in plan view, is trapezoidal and has, on the outer surface of the shoulder section, a boundary edge facing away from the transverse groove, forming the shorter base side of the trapezoid, as well as two boundary edges extending towards the transverse groove, each forming a trapezoidal leg, wherein the boundary edge forming the shorter base side of the trapezoid forms an angle of 125° to 145° with each boundary edge forming a trapezoidal leg, or b) that each recess, viewed in plan view, is triangular in shape and has, on the outer surface of the shoulder portion, two boundary edges extending to the transverse groove, which enclose an angle of 110° to 140° with each other.

[0005] In such angled depressions, the snow is compacted more effectively than before when the tire rolls over a road covered with a correspondingly large amount of snow. The "angled" design of the depressions ensures faster and stronger compaction of the "collected" snow. As a result, the snow is held better in the depressions than before, and the forces transferred to the snow-covered road surface via the effect of snow-on-snow friction are increased, thus improving snow grip, especially when cornering. The selected angles between the boundary edges prevent the concentration of shear stresses, thus maintaining a high level of crack resistance in the rubber material adjacent to the depressions. The trapezoidal depressions are particularly advantageous in this respect.

[0006] According to a first preferred embodiment, the shoulder section of the shoulder-side tread block row has an inside half adjacent to the lateral edge of the ground contact patch and an outside half, with the entire recesses being formed in the outside half. This contributes to a particularly advantageous compromise between snow performance and the crack resistance of the rubber material.

[0007] It is also preferred if - in variant a) the boundary edge forming a trapezoidal leg, which is closer to the side wall, or - in variant b), the boundary edge closer to the sidewall has a distance of at least 2.0 mm from an edge bordering the outer surface of the shoulder section, measured transversely to the circumferential direction at the level of the outer surface. This contributes to good crack resistance of the rubber material adjacent to the recess.

[0008] A further preferred embodiment provides that the recesses are each delimited by a base and surfaces extending from the boundary edges.

[0009] According to a first preferred development of this design, the bottom of each recess runs parallel to the outer surface of the shoulder section. This contributes to a good grip of the snow accumulating in the recesses.

[0010] According to a second preferred development of the latter embodiment, the bottom at the transverse groove is delimited by a bottom edge which has an edge length of 75% to 88%, in particular of up to 85%, of the maximum length of the recess.

[0011] According to a third preferred development of the last-mentioned preferred embodiment, the base, viewed in plan view, has a reduced trapezoidal or triangular shape of the depression. This contributes to a further improvement in snow performance.

[0012] For the desired compaction of the accumulated snow in the depression, it is also advantageous if, in variant a), the boundary edge forming the shorter base side of the trapezoid has a length of 50% to 65%, preferably 55% to 60%, of the maximum length of the depression.

[0013] According to a further preferred embodiment, the transverse grooves include those in which a pair of opposing depressions is formed, separated from each other by the transverse groove. This measure also contributes to improving snow grip.

[0014] In the last-mentioned preferred embodiment, it is advantageous if the depressions belonging to a pair have an offset of at most 1.5 mm from one another, the offset being determined perpendicularly between two auxiliary lines running in the circumferential direction, wherein in variant a) the auxiliary lines run through the ends lying on the transverse groove of the boundary edge forming one trapezoidal leg and lying closer to the side wall, and wherein in variant b) the auxiliary lines run through the ends lying on the transverse groove of the boundary edge lying closer to the side wall.

[0015] A further preferred embodiment is characterized in that the transverse grooves on which the depressions are formed each have a main section running in the inner section and in the shoulder section of the shoulder-side profile block row and a run-out section adjoining this via a kink and running at an angle of 50° to 80°, in particular of 55° to 70°, to the circumferential direction, wherein the depressions are formed on the run-out section.

[0016] A further preferred embodiment is characterized in that the maximum depth of the depressions 0.7 mm to 1.5 mm, preferably 0.8 mm to 1.2 mm, and / or the maximum length of the depressions is 10.0 mm to 12.0 mm and / or the maximum width of the depressions is up to 40%, in particular up to 35%, preferably 20% to 30%, of the maximum length.

[0017] A further preferred embodiment is characterized in that, in variant a), the angle formed by the boundary edge forming the shorter base side of the trapezoid with each boundary edge forming a trapezoid leg is 130° to 140°, in particular up to 137°. This is particularly favorable for snow grip.

[0018] Further features, advantages and details of the invention will now be described in more detail with reference to the drawing, which schematically shows an embodiment of the invention. Fig. 1 a plan view of a developed circumferential section of a shoulder-side profile block row of a tread of a pneumatic vehicle tire with an embodiment variant of the invention, Fig. 2 a section along the line II-II of the Fig. 1, Fig. 3 an enlarged plan view of detail Z3 of the Fig. 1, Fig. 4 a section along the line IV-IV of the Fig. 3 and Fig. 5 an oblique view according to the Fig. 3 viewing direction indicated by arrow S5.

[0019] Pneumatic vehicle tires designed according to the invention are tires for motor vehicles, in particular for multi-track motor vehicles, preferably for passenger cars (PCs), vans (transporters) or SUVs, and preferably tires of radial design for rims with an integer rim diameter of 13 inches to 24 inches, in particular of 18 inches to 23 inches, wherein the tires are intended in particular for driving under winter driving conditions.

[0020] Fig. 1 shows a circumferential section of a shoulder-side profile block row 1, which is formed on the inside of the tread by a radially directed groove to the respective intended profile depth T UR (marked in Fig. 2) is limited by a circumferential groove 2, typically 6.5 mm to 13.0 mm wide. Preferably, a further shoulder-side tread block row is formed in the second tread shoulder (not shown), similar to the shoulder-side tread block row 1 and oriented at a 180° angle. The lateral edge of the ground contact patch running in the area of ​​the shoulder-side tread block row 1 (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 L.

[0021] The shoulder-side tread block row 1 has an inner section 3 located within the ground contact patch, running circumferentially, with an outer surface 3a located in the tread periphery, and a shoulder section 4 located outside the ground contact patch, running circumferentially, extending to the sidewall (not shown), with an outer surface 4a tangentially adjoining the outer surface 3a. The shoulder section 4 has an inner half 4' adjacent to the lateral edge of the ground contact patch (line L), an outer half 4", and a width bs measured transversely to the circumferential direction at the level of the outer surface 4a, thus up to the edge 5. The "division" of the shoulder section 4 into the halves 4', 4" therefore refers to the width bs.The shoulder section 4 and its outer surface 4a end in the direction of the side wall at a peripheral edge 5, which runs around the circumference and is adjoined by an inwardly curved transition flank 6 running towards the side wall (not shown) (cf. Fig. 5).

[0022] The shoulder-side tread block row 1 is provided with a plurality of transverse grooves 7, 8 over its circumferential extent, wherein in the circumferential direction one transverse groove 7 follows a transverse groove 8. The transverse grooves 7, 8 open into the circumferential groove 2, emerge towards the sidewall at the transition flank 6, structure the shoulder-side tread block row 1 into tread blocks 1a, run in a curved manner when viewed in plan view, and have, on the tread periphery, a groove edge 9 on the inside of the curve and a groove edge 10 on the outside of the curve, wherein the groove edges 9, 10 are each composed of a section running on the outer surface 3a and a section running on the outer surface 4a. The inside groove edge 9 of the sheet is the one in which a shortest possible auxiliary line h1 connecting the ends of the groove edge 9 and running at the level of the outer surfaces 3a, 4a runs completely outside the transverse groove 7, 8.The transverse grooves 7, 8 furthermore each have a groove center line m which, in plan view, is spaced at the same distance from the groove edges 9, 10 and follows the groove course. QR , one in plan view perpendicular to the groove center line m QR and width b determined between the groove edges 9, 10 QR ( Fig. 2, shown for transverse groove 7) from 3.0 mm to 6.0 mm and in radial direction a maximum depth t QR ( Fig. 2, depth at the deepest point) of 70% to 100%, in particular up to 95%, of the tread depth T UR ( Fig. 2), whereby the transverse grooves 7, 8 become shallower towards their end located in the outer half 4" in a manner known per se. "Perpendicular to the groove center line m QR “ means perpendicular to a tangent which is drawn to the respective position of the groove center line m QR is created.

[0023] The transverse grooves 7, 8 run - viewed in plan view and relative to a the ends of the groove center line m QR connecting, shortest possible auxiliary line h2 - to the axial direction at an angle α of 0° to 15°, in particular of up to 10°, wherein the transverse grooves 7, 8 run parallel to one another with respect to the auxiliary line h2 or whose angles α deviate from one another by in particular up to 3°.

[0024] Each transverse groove 7, 8 is formed by a groove flank 11 extending from the groove edge 9 (cf. Fig. 2), a groove flank 12 starting from the groove edge 10 (cf. Fig. 2) and a groove base 13 (cf. Fig. 2) and, viewed in plan view, is composed of a main section 7a (transverse groove 7), 8a (transverse groove 8) which opens into the shoulder-side circumferential groove 2 and runs over the entire inner section 3 and in the inner half 4', and an outlet section 7b (transverse groove 7), 8b (transverse groove 8) designed as a shallow depression.

[0025] In the case of the transverse grooves 8, the “division” into the main section 8a and the outlet section 8b takes place at a Fig. 1 barely noticeable and not marked break point k1 (see Fig. 3) the groove center line m QR The run-off section 8b runs according to Fig. 3 - relative to a distance between the bending point k1 and the end of the groove center line m QRstraight auxiliary line h3 - to the circumferential direction at an angle β of 50° to 80°, in particular of 55° to 70°, and has a determined at the level of the outer surface 4a and therefore up to the edge 5, on the groove center line m QR relative length c measured transversely to the circumferential direction b from 35% to 50%, in particular up to 45%, of the width bs ( Fig. 1) of the shoulder section 4.

[0026] How Fig. 1 shows, on each transverse groove 8 in the outer half 4" of the shoulder section 4 adjacent to the run-out section 8b, a pair of surface depressions 14, 15 are formed, which extend from the outer surface 4a, are elongated along the groove edges 9, 10, i.e. in the extension direction of the run-out section 8b, and are separated from each other in the circumferential direction by the run-out section 8b. The depression 14 is formed on the inside groove edge 9 and the depression 15 is formed on the outside groove edge 10. As Fig. 3 shows, the recesses 14, 15, viewed in plan view onto the outer surface 4a, are each formed in the shape of a substantially isosceles trapezoid, the trapezoid base being located at the outlet section 8b.

[0027] According to Fig. 3 and Fig. 5, the recess 14, 15 has on the outer surface 4a a boundary edge 16a facing away from the outlet section 8b and forming the shorter base side of the trapezoid, a boundary edge 16b forming one trapezoid leg and located closer to the side wall, and a boundary edge 16b forming the other trapezoid leg and located closer to the shoulder-side circumferential groove 2 (cf. Fig. 1) located boundary edge 16c. The boundary edges 16b, 16c extend to the outlet section 8b. As Fig. 3 shows, the boundary edge 16a, viewed in plan view, runs parallel to an auxiliary line h4, which runs straight between the ends of the boundary edges 16b, 16c located at the outlet section 8b, wherein the boundary edge 16a, also viewed in plan view, encloses with the boundary edges 16b, 16c an angle γ of 125° to 145°, in particular of 130° to 140°, preferably of up to 137°, determined via the respective depression 14, 15, in particular by a maximum of 5.0°, preferably by a maximum of 2.0°.

[0028] How Fig. 3 and Fig. 5 further show, the recess 14, 15 has a maximum length cv (length at the longest point) of 7.0 mm to 15.0 mm, preferably 10.0 mm to 12.0 mm, determined along the already mentioned auxiliary line h4, a maximum width bv (width at the widest point) measured between the auxiliary line h4 and the boundary edge 16a and perpendicular to the auxiliary line h4 of 18% to 50%, in particular of up to 40%, preferably of up to 35%, particularly preferably 20% to 30%, of the maximum length cv and a distance av ( Fig. 3) of at least 2.0 mm. The maximum width bv is therefore measured perpendicular to the maximum length cv.

[0029] The angles γ, the maximum length cv and the maximum width bv are preferably coordinated in such a way that the boundary edge 16a has a length c a ( Fig. 3) from 50% to 65%, preferably from 55% to 60%, of the maximum length cv of the recess 14, 15, wherein in determining the length c a any transition curves located at the mutual connection of the boundary edges 16a, 16b, 16c are disregarded, so that the determination of the length c a in such a way as if the boundary edges 16a, 16b, 16c were continued over the transition curves.

[0030] The recesses 14, 15 are each delimited by a base 17d, an inner surface 17a adjoining the boundary edge 16a, a surface 17b adjoining the boundary edge 16b and a surface 17c adjoining the boundary edge 16c. According to Fig. 4, the surfaces 17a, 17b, 17c, viewed in the cross-section perpendicular to the associated boundary edge 16a, 16b, 16c in plan view, run along a circular arc and adjoin tangentially to the base 17d (in Fig. 4 for the surfaces 17a). The bottom 17d runs parallel to the outer surface 4a, has Fig. 3, viewed in plan view, has in reduced form the trapezoidal shape of the recess 14, 15 and has a bottom edge 17d' located at the outlet section 8b (cf. Fig. 5) with an edge length c K ( Fig. 5) from 75% to 88%, in particular up to 85%, of the length cv ( Fig. 3, Fig. 5) of the depression 14, 15. The depression 14, 15 further has a constant depth tv ( Fig. 4) from 0.5 mm to 2.0 mm, in particular from 0.7 mm to 1.5 mm, preferably from 0.8 mm to 1.2 mm.

[0031] How Fig.As Figure 3 further shows, the recess 14 is located opposite the recess 15 such that they have a mutual offset vv of at most 1.5 mm. The offset vv is determined perpendicularly between two auxiliary lines h5 running in the circumferential direction, wherein one auxiliary line h5 runs through the end of the boundary edge 16b of the recess 14 located at the outlet section 8b, and the other auxiliary line h5 runs through the end of the boundary edge 16b of the recess 15 located at the outlet section 8b.

[0032] The invention is not limited to the described embodiment.

[0033] The depressions can be triangular, in particular in the shape of an isosceles triangle, when viewed in plan view, and can have two boundary edges on the outer surface of the shoulder section that extend to the respective transverse groove and that form an angle of 110° to 140° with each other. The depressions can also be formed in the inner half of the shoulder section. Only a single depression can be provided on each transverse groove. The transverse grooves can end on the inside of the tread within the shoulder-side tread block row and have a course that deviates from the described course. Therefore, when viewed in plan view, the transverse grooves can be straight or continuously curved. For straight transverse grooves, their angle α refers to the groove center line m. QR and in the case of non-straight transverse grooves, the ends of the groove center line m QRconnecting auxiliary line h2. The bottom of the depressions may be inclined relative to the tread periphery so that the depth of the depressions varies over their extent, with the maximum depth (depth at the deepest point) of the depressions being 0.5 mm to 1.3 mm, in particular 0.7 mm to 1.2 mm. List of reference symbols 1 shoulder-side tread block row 1a profile block 2 circumferential grooves 3 Interior section 3a Outer surface 4 shoulder section 4a Outer surface 4' inside half 4" outside half 5 Edge 6 transition flank 7 transverse groove 7a Main section 7b Run-off section 8 transverse grooves 8a Main Section 8b run-off section 9 Groove edge 10 groove edge 11 Groove flank 12 groove flank 13 Groove base 14 Deepening 15 Deepening 16a boundary edge 16b boundary edge 16c boundary edge 17a inside surface 17b Area 17c area 17d floor 17d' bottom edge a V Distance b QR , b S Width b V maximum width c a , c b length c V maximum length c K Edge length h1, h2, h3, h4, h5 auxiliary line k1 break point L line (lateral edge of the ground contact area) m QR Groove centerline S5 Arrow (direction of view) t QR maximum depth T UR Tread depth t V depth v V Offset Z3 Detail α, β, γ angles QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2019 218 845 A1

[0002]

Claims

[1] Vehicle pneumatic tire with a tread having at least one shoulder-side tread block row (1) which has an inner section (3) located within the ground contact area, a shoulder section (4) located outside the ground contact area and transverse grooves (7, 8), wherein in the shoulder section (4) adjacent to transverse grooves (8) elongated depressions (14, 15) with a maximum depth (tv) of 0.5 mm to 2.0 mm, a maximum length (cv) present at the transverse groove (7, 8) of 7.0 mm to 15.0 mm and a maximum width (bv) of 18% to 50% of the maximum length (cv) are formed along the respective transverse groove (8), characterized by , a) that each depression (14, 15), viewed in plan view, is trapezoidal and has on the outer surface (4a) of the shoulder section (4) a boundary edge (16a) facing away from the transverse groove (8), forming the shorter base of the trapezoid, and two boundary edges (16b, 16c) extending towards the transverse groove (8), each forming a leg of the trapezoid, wherein the boundary edge (16a) forming the shorter base of the trapezoid forms an angle (γ) of 125° to 145° with each boundary edge (16b, 16c) forming a leg of the trapezoid or b) that each depression, viewed from above, is triangular in shape and has two boundary edges extending to the transverse groove (8) on the outer surface (4a) of the shoulder section (4), which enclose an angle of 110° to 140° with each other. [2] Vehicle pneumatic tires according to claim 1, characterized by, that the shoulder section (4) of the shoulder-side profile block row (1) has an inner half (4') adjacent to the lateral edge of the ground contact surface (line L) and an outer half (4"), wherein the complete recesses (14, 15) are formed in the outer half (4"). [3] Vehicle pneumatic tires according to claim 1 or 2, characterized by , that - in variant a) the boundary edge (16b) forming one leg of the trapezoid, which is closer to the side wall, or - in variant b) the boundary edge which is closer to the side wall, has a distance (av) of at least 2.0 mm perpendicular to the circumferential direction at the level of the outer surface (4a) to an edge edge (5) which defines the outer surface (4a) of the shoulder section (4). [4] Vehicle pneumatic tires according to any one of claims 1 to 3, characterized by, that the depressions (14, 15) are each bounded by a bottom (17d) and surfaces (17a, 17b, 17c) extending from the boundary edges (16a, 16b, 16c). [5] Vehicle pneumatic tire according to claim 4, characterized in that the bottom (17d) of each depression (14, 15) runs parallel to the outer surface (4a) of the shoulder section (4). [6] Vehicle pneumatic tires according to claim 4 or 5, characterized by , that the floor (17d) at the transverse groove (8) is bounded by a floor edge (17d') which has an edge length (c K ) of 75% to 88%, in particular of up to 85%, of the maximum length (cv) of the depression (14, 15). [7] Vehicle pneumatic tires according to any one of claims 4 to 6, characterized by , that the floor (17d), viewed from above, has in reduced form the trapezoidal shape or the triangular shape of the depression (14, 15). [8] Vehicle pneumatic tires according to any one of claims 1 to 7, characterized by, that in variant a) the boundary edge (16a) forming the shorter base of the trapezoid has a length (c a ) of 50% to 65%, preferably of 55% to 60%, of the maximum length (cv) of the recess (14, 15). [9] Vehicle pneumatic tires according to any one of claims 1 to 8, characterized by , that the transverse grooves (8) include those in which each pair of opposite depressions (14, 15) is formed, separated from each other by the transverse groove (8). [10] Vehicle pneumatic tires according to claim 9, characterized by , that the recesses (14, 15) belonging to a pair have an offset (vv) of at most 1.5 mm to each other, wherein the offset (vv) is determined perpendicularly between two circumferentially extending auxiliary lines (h5), where in variant a) the auxiliary lines (h5) run through the ends of the boundary edge (16b) that forms one leg of the trapezoid and is closer to the side wall, which lie on the transverse groove (8) and in variant b) the guide lines run through the ends of the boundary edge closer to the side wall that lie on the transverse groove (8). [11] Vehicle pneumatic tires according to any one of claims 1 to 10, characterized by , that the transverse grooves (8) on which the depressions (14, 15) are formed each have a main section (8b) running in the inner section (3) and in the shoulder section (4) of the shoulder-side profile block row (1) and a run-out section (8b) adjoining this via a kink (k1), running at an angle (β) of 50° to 80°, in particular of 55° to 70°, to the circumferential direction, wherein the depressions (14, 15) are formed on the run-out section (8b). [12] Vehicle pneumatic tires according to any one of claims 1 to 11, characterized by , that - the maximum depth (tV) of the recesses (14, 15) 0.7 mm to 1.5 mm, preferably 0.8 mm to 1.2 mm, and / or - the maximum length (cv) of the recesses (14, 15) 10.0 mm to 12.0 mm and / or - the maximum width (bv) of the recesses (14, 15) is up to 40%, in particular up to 35%, preferably 20% to 30%, of the maximum length (cv). [13] Vehicle pneumatic tires according to any one of claims 1 to 12, characterized by , that in variant a) the angle (γ) which the boundary edge (16a) forming the shorter base of the trapezoid encloses with each boundary edge (16b, 16c) forming a leg of the trapezoid is 130° to 140°, in particular up to 137°.

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