Vehicle tyre, in particular commercial vehicle tyre

Abstract

The invention relates to a vehicle tyre, in particular a commercial vehicle tyre, having a tread with at least one profile rib (1, 1', 1'') with sipes (3, 3', 3'') having a width (bE) of 0.40 mm to 1.60 mm and a maximum depth (tE) of at least 2.0 mm, wherein the sipes (3, 3', 3''), as seen in a plan view in cross section extending perpendicular to the sipe centre line (mE), extend with respect to the radial direction at an angle (β) of 10° to 45° in relation to the sipe centre plane (ME). The maximum depth (tE) of the sipes (3, 3', 3'') is at most 25% of the profile depth (TP), wherein the sipes (3, 3', 3'') include those which, seen in a plan view, extend in parallel and directly adjacent to one another and have mutual spacings (a1, a1'') of 1.0 mm to 10.0 mm determined perpendicularly between the sipe centre lines (mME).

Description

[0001] 202301041 1 Description Vehicle tire, in particular commercial vehicle tire The invention relates to a vehicle tire, in particular a commercial vehicle tire, with a tread having at least one tread rib with cuts having a width of 0.40 mm to 1.60 mm and a maximum depth of at least 2.0 mm, wherein the cuts, viewed in the cross-section running perpendicular to the cut center line in plan view, run at an angle of 10° to 45° to the radial direction with respect to the cut center area. A vehicle tire of this type is known, for example, from AT 367690 B. The vehicle tire has a tread with a tread rib which is provided with cuts which, viewed in cross-section, run at an angle of at most 45° to the radial direction. In the exemplary embodiment shown, the cuts have a maximum depth on the order of magnitude of the tread depth.As the tire rolls, the angle of the cuts increases under the resulting load. The tire should have good grip on snow and ice as tread wear progresses. EP 0846579 A2 discloses a vehicle tire with a tread with profile positives with cuts that run essentially in the axial direction in plan view and have a width of 0.3 mm to 1.0 mm. Viewed in plan view, the cuts have a wave-shaped cut section which, viewed in cross-section, runs at an angle of 20° to 70°, in particular of 30° to 50°, in this embodiment of 45°, to the radial direction. This pneumatic vehicle tire is supposed to have good grip properties on wet and dry road surfaces.When designing cuts, there is a conflict of objectives between the improved grip of the tread on a road surface covered with ice and / or snow, which the cuts are intended to achieve, and the reduction in stiffness of the respective tread rib associated with the cuts, which impairs dry performance. The invention is based on the object of improving the dry performance of a pneumatic vehicle tire of the type mentioned at the outset while maintaining the highest possible grip on a road surface covered with snow and / or ice. This object is achieved according to the invention in that the maximum depth of the cuts amounts to a maximum of 25% of the tread depth, the cuts including those which, viewed in plan view, run parallel and immediately adjacent to one another and have mutual distances of 1.0 mm to 10.0 mm, determined perpendicularly between the cut center lines.The cuts are therefore clearly limited in depth and act as surface micro-grip elements, which significantly improve the grip properties, especially on new or slightly worn tires. Due to the small distances between the cuts, the tread segments located between the cuts continue to exhibit particularly favorable deformation behavior when the tread flattens, whereby the cut edges have a particularly beneficial effect on snow and ice grip. Because the cuts are significantly shallower than conventional cuts, the tread rib has greater rigidity, which improves dry performance. According to a preferred embodiment, the mutual distances between the cut center lines of the cuts, which, viewed in plan view, run parallel and immediately adjacent to one another, are up to 8.0 mm, in particular up to 6.0 mm, preferably up to 4.0 mm.This is beneficial for the deformation behavior when the tread flattens, so that snow and ice grip is further improved. 202301041 3 A further preferred embodiment provides that the cuts, which have the aforementioned mutual spacings, are arranged within groups of at least two cuts each, with cuts belonging to the same group being located in a separate tread rib circumferential section, which is delimited by two lines running transversely to the circumferential direction in plan view, with the lines running through the points of the cuts that are furthest apart from one another in the circumferential direction. This ensures that the cuts function effectively over the circumference of the tread rib and is thus further advantageous for grip on snow and ice.In the latter embodiment, a first advantageous development consists in the fact that the groups include adjacent groups in the circumferential direction, which - based on the closest lines to each other - have a distance determined in the circumferential direction of 5.0 mm to 40.0 mm, in particular of 10.0 mm to 35.0 mm, and preferably of 15.0 mm to 30.0 mm. This contributes to a particularly favorable balance between grip on roads covered with snow and / or ice and dry performance. A preferred variant of the first advantageous development provides that the mutual distances of the incisions arranged within a group correspond, wherein the distance between the adjacent groups in the circumferential direction is at least 200%, in particular at least 300%, preferably at least 400%, of a mutual distance.This contributes primarily to maintaining high tread rigidity and is therefore beneficial for dry performance. In the last-mentioned embodiment, according to a second advantageous further development, the groups include groups which each have up to seven, in particular up to five, cuts. Such a number of cuts is also particularly beneficial with regard to the conflict of objectives existing between grip on a road surface covered with snow and / or ice and dry performance. 202301041 4 A third advantageous further development of the last-mentioned preferred embodiment is characterized in that the groups include groups in which the cuts, viewed in plan view, run at an angle of 0° to 50° to the axial direction, in particular of 0° or in particular of 10° to 45°, preferably of 15° to 40°, particularly preferably of 20° to 35°, and most preferably of 25° to 30°.Depending on the angle, the cuts improve the grip properties, especially under axial force, such as occurs when cornering, or primarily under circumferential force, which occurs particularly under traction and braking loads.In the third advantageous further development, it is preferred if the tread is designed to be directional, wherein the cuts each have an incoming cut edge which first enters the ground when the tire rolls during forward travel and a outgoing cut edge, wherein the cuts, viewed in a cross-section oriented perpendicular to their cut center line in plan view, run inclined relative to the radial direction and the rolling direction during forward travel in such a way that a first auxiliary line running in the radial direction and through the incoming cut edge does not intersect the cut center surface and a second auxiliary line running in the radial direction and through the outgoing cut edge has an intersection point with the cut center surface.Such inclined cuts have particularly effective cut edges under braking load and therefore contribute primarily to improving braking performance on ice and / or snow. Furthermore, in the third advantageous development, it is preferred if the cuts traverse the tread rib. A fourth advantageous development of the last-mentioned preferred embodiment is characterized in that the groups include groups in which the cuts run at an angle of 0° to 15°, 202301041 5 in particular of up to 10°, particularly preferably of 0°, to the circumferential direction, wherein the cuts end on both sides within the tread rib. Such groups are particularly suitable for locally "softening" the tread rib and, especially under forces acting in the axial direction, contribute to improving grip on road surfaces covered with snow and / or ice.In the fourth advantageous further development, it is advantageous if the sipes have a length of 10.0 mm to 30.0 mm, in particular 15.0 mm to 25.0 mm, projected in the circumferential direction relative to the sipe centerline. This contributes to maintaining high rigidity of the tread rib and is thus particularly advantageous for the conflicting objectives between grip on snow and / or ice-covered roads and dry performance. A fifth advantageous further development of the last-mentioned preferred embodiment is characterized in that the groups include groups in which the sipes are symmetrical with respect to a line running parallel to the sipe centerlines of the sipes in plan view. This contributes to a uniform local reduction in the rigidity of the tread rib, which is advantageous, for example, for abrasion behavior and dry performance.A sixth advantageous development of the last-mentioned preferred embodiment is characterized in that the groups include groups in which the angles at which the incisions run to the radial direction, viewed in a cross-section perpendicular to the incision center line in plan view, are the same. According to a further preferred embodiment, the angle at which the incisions run to the radial direction, viewed in a cross-section perpendicular to the incision center line in plan view, is 15° to 40°, in particular 20° to 35°, preferably 25° to 30°. 202301041 6 Further features, advantages, and details of the invention will now be described in more detail with reference to the drawing, which schematically shows exemplary embodiments of the invention. In this case, Fig.1 is a plan view of a circumferential section of a profile rib of a tread of a commercial vehicle tire with a first embodiment of the invention, Fig. 1a is an enlarged section along the line Ia-Ia of Fig. 1, Fig. 2 is a plan view of a circumferential section of a profile rib with a second embodiment of the invention, and Fig. 3 is a plan view of a circumferential section of a profile rib with a third embodiment of the invention, developed into a plane. Vehicle tires designed according to the invention are tires for motor vehicles, in particular for multi-track motor vehicles and preferably pneumatic vehicle tires of radial design for rims with a rim diameter of 13 inches to 24 inches. The tires are preferably commercial vehicle tires which in particular have a rim diameter of 17.5, 19.5 or 22.5 inches. Fig. 1 to Fig.3 each show a developed view of a circumferential section of a central tread rib 1 (Fig. 1), 1' (Fig. 2), 1'' (Fig. 3) of a tread of a commercial vehicle tire. The tread rib 1, 1', 1'' is delimited laterally by circumferential grooves 2 which, in the exemplary embodiments shown, run straight in plan view and which are designed in the radial direction at the respectively intended tread depth TP (indicated in Fig. 1a), which for commercial vehicle tires is preferably 10.0 mm to 25.0 mm. The tread rib 1, 1', 1'' has an outer rib surface 1a located in the tread periphery and two rib edges 1b delimiting said outer rib surface and located on the circumferential grooves 2.Furthermore, the profile rib 1, 1', 1'' is provided with a number 202301041 7 of incisions 3 (profile rib 1), 3' (profile rib 1'), 3'' (profile rib 1'') which, when viewed from the outer surface 1b of the rib, are elongated and straight, wherein the incisions 3, 3', 3'' are arranged in circumferentially successive groups G (incisions 3), G' (incisions 3'), G'' (incisions 3''). The incisions 3, 3', 3' each have two incision edges 41, 42 located at the level of the rib outer surface 1a, aligned in their longitudinal extent, running parallel to each other and are each delimited by two incision walls 5 extending from the incision edges 41, 42 (Fig.1a: shown for incision 3) and an incision base 6 (Fig.1a: shown for incision 3).The incisions 3, 3', 3'' furthermore each have an incision center line mE located at the level of the rib outer surface 1a, in plan view following the course of the respective incision 3, 3', 3'', spaced correspondingly to the incision edges 41, 42, an incision center surface ME extending from the incision center line mE and spaced correspondingly to the incision walls 5 (Fig. 1a: shown for incision 3), a constant width bE determined perpendicular to the incision center surface ME (Fig. 1a) of 0.4 mm to 1.6 mm, in particular of 0.8 mm to 1.4 mm, and a maximum depth tE determined in the radial direction and constant in the exemplary embodiments (depth at the deepest point, Fig. 1a: shown for incision 3) of at least 2.0 mm and at most 25% of the profile depth TP (Fig. 1a). on.Each group G, G' is formed by three incisions 3, 3' and each group G'' is formed by two incisions 3'', wherein the incisions 3, 3', 3'' belonging to the same group G, G', G'', viewed in plan view and with respect to their incision center lines mE, run parallel to one another and are located in a tread rib circumferential section U which is delimited by two lines L running transversely to the circumferential direction in plan view, wherein the lines L run through the points of the incisions 3, 3', 3'' which are furthest apart from one another in the circumferential direction on the tread periphery, i.e. on the rib outer surface 1a. The incisions 3, 3' each include two edge incisions 3, 3' and one central incision 3, 3' running between the edge incisions 3, 3'.202301041 8 Within each group G, G', G'' the sipes 3, 3', 3'' are formed symmetrically with respect to a line LS which, in plan view, runs parallel to the sipe center lines mE of the sipes 3, 3', 3'', wherein the line LS for each group G, G', viewed in plan view, coincides with the sipe center line mE of the central sipe 3, 3' and for each group G'', viewed in plan view, runs in the region between the sipe center lines mE of the two sipes 3''. The tread, which has the profile rib 1 shown in Fig.1, is designed to be directional in a manner not shown, wherein the commercial vehicle tire is to be mounted on a vehicle, for example a truck, in such a way that it has the rolling direction symbolized by the arrow R when driving forward.The sipes 3 of groups G, viewed in plan view and relative to the sipe center lines mE, run at an angle α of 0° to the axial direction and traverse the central tread rib 1, so that they open into the circumferential grooves 2. As a result of the directional design of the tread and the orientation of the sipes 3 to the axial direction (angle α), as the tire rolls forward, at each sipe 3, the sipe edge 41 penetrates the ground before the sipe edge 42. The sipe edge 41 is hereinafter referred to as the leading sipe edge 41 and the sipe edge 42 is hereinafter referred to as the trailing sipe edge 42.The immediately adjacent incisions 3 belonging to a group G have, viewed in plan view, mutual distances a1 of 1.0 mm to 10.0 mm, in particular up to 8.0 mm, preferably up to 6.0 mm, particularly preferably up to 4.0 mm, based on the incision center lines mE and determined perpendicular to these. Furthermore, immediately adjacent, i.e. consecutive, groups G in the circumferential direction - based on the closest lines L to one another - have a distance a2 from one another determined in the circumferential direction, which is 5.0 mm to 40.0 mm, in particular 10.0 mm to 35.0 mm, and preferably 15.0 mm to 30.0 mm. Preferably, the distances a1, a2 are additionally coordinated with one another such that each distance a2 is at least 200%, in particular at least 300%, preferably at least 400%, of a distance a1. 202301041 9 According to Fig.1a, the incisions 3, viewed in a cross-section oriented perpendicular to the associated incision center line mE in plan view (cf. position of line Ia-Ia in Fig. 1), run at an angle β, relative to the incision center surface ME, of 10° to 45°, in particular of 15° to 40°, preferably of 20° to 35°, and particularly preferably of 25° to 30°, to the radial direction, wherein the angles β of the incisions 3 coincide. In Fig. 1a, for an incision 3, an auxiliary line h1 running in the radial direction and through the incoming incision edge 41 and an auxiliary line h2 running in the radial direction and through the outgoing incision edge 42 are shown. The cuts 3 are inclined (angle β) relative to the rolling direction when driving forward (arrow R) in such a way that the auxiliary line h1 does not intersect the cut center surface ME and the auxiliary line h2 has an intersection point S with the cut center surface ME. A tread which has the angle shown in Fig.2, is also designed to be directional in a manner not shown, wherein the commercial vehicle tire is to be mounted on a vehicle in such a way that it has the rolling direction symbolized by the arrow R when driving forward. The sipes 3' therefore each have an incoming sipe edge 41 and an outgoing sipe edge 42. The sipes 3' differ from the sipes 3 (Fig. 1) in that, viewed in plan view and relative to the sipe center lines mE, they run at an angle γ of up to 50° to the axial direction, deviating from 0°. The inclination of the sipes 3' in cross-section relative to the rolling direction when driving forward (arrow R) is analogous to that of the sipes 3 (cf. Fig. 1a: shown for sipes 3, angle β). Furthermore, the incisions 3' located within a group G' – analogous to the incisions 3 (Fig.1) – mutual distances a1 and circumferentially adjacent groups G' – analogous to the groups G (Fig.1) – mutual distances a2. According to Fig.3, the incisions 3'', viewed in plan view and related to the incision center lines mE, run at an angle δ of 0° to the circumferential direction and axially next to one another within each group G'', wherein the incisions 3'' are spaced from the rib edges 1b and end closed on both sides within the 202301041 10 profile rib 1''. The incisions 3'' each have a length cE, related to the incision center line mE and projected in the circumferential direction, of 10.0 mm to 30.0 mm, in particular of 15.0 mm to 25.0 mm. The incisions 3'' belonging to a group G'' have mutual distances a1'' of 1.0 mm to 4.0 mm, based on the incision center lines mE and determined perpendicular to these.Groups G'' which follow one another in the circumferential direction have - based on the associated nearest lines L - a distance a2'' determined in the circumferential direction, which is 5.0 mm to 40.0 mm, in particular 10.0 mm to 35.0 mm, and preferably 15.0 mm to 30.0 mm. Preferably, the distances a1'', a2'' are additionally coordinated with one another such that each distance a2'' is at least 200%, in particular at least 300%, preferably at least 400% of a distance a1''. The arrangement of the group G'' is further such that the incisions 3'' which belong to different groups G'' run in alignment with one another in plan view. The incision 3'' located closest to a rib edge 1b in each group G'' has a distance a3'' of at least 3.0 mm from the nearest rib edge 1b - based on its incision center line mE - determined on the rib outer surface 1a in the axial direction.The incisions 3'' belonging to a group G'' can have different lengths cE. The invention is not restricted to the described embodiments. The tread has at least one tread rib with incisions running around the circumference. The tread rib(s) can be structured in a block-like manner with transverse grooves passing through it in tread blocks and / or with transverse grooves ending in a blind groove. The tread rib is bordered on at least one side by a circumferential groove which, in plan view, runs in any desired manner, for example in a zigzag shape. Furthermore, the incisions can be straight in plan view, for example, or can be curved or wavy overall or in sections. In the case of incisions which are curved or wavy at least in sections, the incision center lines follow the curved orA wave-like pattern, wherein the angle at which such incisions extend in plan view to the axial direction is determined with respect to a line connecting the ends of the incision center line and extending straight in plan view. Each group comprises, in particular, two to seven incisions. The incisions do not have to be arranged in groups.

[0002] 202301041 12 List of reference symbols 1, 1', 1'' ....................... middle profile rib 1a ............................... rib outer surface 1b ............................... rib edge 2................................. circumferential groove 3, 3', 3'' ....................... notch 41, 42........................... notch edge 5.................................. notch wall 6.................................. notch base a1, a2, a1'', a2'', a3'' ...... distance bE ................................ width cE ................................ length G, G', G''..................... group h1, h2........................... auxiliary line L ................................. line LS ................................ line mE ............................... notch center line ME ............................... notch center surface R ................................. arrow (rolling direction) S ................................. intersection point tE .................................Maximum depth TP ............................... Profile depth U ................................. Profile rib circumferential section α, β, γ, δ ..................... Angle.

Claims

202301041 13 Patent Claims 1. Vehicle tire, in particular commercial vehicle tire, with a tread with at least one profile rib (1, 1', 1'') with cuts (3, 3', 3'') with a width (bE) of 0.40 mm to 1.60 mm and a maximum depth (tE) of at least 2.0 mm, wherein the cuts (3, 3', 3''), viewed in the cross-section running perpendicular to the cut center line (mE) in plan view, run to the radial direction at an angle (β) of 10° to 45° with respect to the cut center area (ME), characterized in that the maximum depth (tE) of the cuts (3, 3', 3'') is at most 25% of the profile depth (TP), wherein the cuts (3, 3', 3'') include cuts which, viewed in plan view, run parallel and immediately adjacent to one another and have mutual distances (a1, a1'') of 1.0 mm to 10.0 mm, measured perpendicularly between the incision center lines (mME). 2.Vehicle tire according to claim 1, characterized in that the mutual distances (a1, a1'') between the incision center lines (mME) of the incisions (3, 3', 3''), which, viewed in plan view, run parallel and immediately adjacent to one another, are up to 8.0 mm, in particular up to 6.0 mm, preferably up to 4.0 mm.

3. Vehicle tire according to claim 1 or 2, characterized in that the incisions (3, 3', 3''), which have the mutual distances (a1, a1''), are arranged within groups (G, G', G'') each having at least two incisions (3, 3', 3''), wherein incisions (3, 3', 3'') belonging to the same group (G, G', G'') are located in a separate tread rib circumferential section (U), which is delimited by two lines (L) running transversely to the circumferential direction in plan view, wherein the lines (L) run through the points of the incisions (3, 3', 3'') which are spaced apart from one another the furthest in the circumferential direction. 202301041 14 4. Vehicle tire according to claim 3, characterized in that the groups (G, G', G'') include groups (G, G', G'') which are adjacent in the circumferential direction and which - based on the lines (L) closest to one another - have a distance (a2, a2'') determined in the circumferential direction of 5.0 mm to 40.0 mm, in particular of 10.0 mm to 35.0 mm, and preferably of 15.0 mm to 30.0 mm.

5. Vehicle tire according to claim 4, characterized in that the mutual distances (a1, a1'') of the incisions (3, 3', 3'') arranged within a group (G, G', G'') correspond, wherein the distance (a2) exhibited by the circumferentially adjacent groups (G, G', G'') is at least 200%, in particular at least 300%, preferably at least 400%, of a mutual distance (a1, a1'').Vehicle tire according to one of claims 3 to 5, characterized in that the groups (G, G', G'') include groups (G, G', G'') which each have up to seven, in particular up to five, incisions (3, 3', 3'').

7. Vehicle tire according to one of claims 3 to 6, characterized in that the groups (G, G', G'') include groups (G, G') in which the incisions (3, 3'), viewed in plan view, extend at an angle (α, γ) to the axial direction of 0° to 50°, in particular of 0° or in particular of 10° to 45°, preferably of 15° to 40°, particularly preferably of 20° to 35°, and most preferably of 25° to 30°.Vehicle tire according to claim 7, characterized in that the tread is designed to be directional, the cuts (3) each having an incoming cut edge (41) which first enters the ground when the tire rolls during forward travel (arrow R) and an outgoing cut edge (42), the cuts (3), viewed in a cross-section oriented perpendicular to their cut center line (mE) in plan view, running at an angle to the radial direction and the rolling direction during forward travel (arrow R) in such a way that a cut edge which is in the radial direction and by the incoming cut edge (41) first enters the ground when the tire rolls during forward travel (arrow R). 202301041 15 The first auxiliary line (h1) running along the incision edge (41) does not intersect the incision center surface (ME), and a second auxiliary line (h2) running in the radial direction and through the tapered incision edge (42) has an intersection point (S) with the incision center surface (ME).

9. The vehicle tire according to claim 7 or 8, characterized in that the incisions (3, 3') pass through the tread rib (1, 1').

10. The vehicle tire according to one of claims 3 to 8, characterized in that the groups (G, G', G'') include groups (G'') in which the incisions (3'') run at an angle (δ) of 0° to 15°, in particular of up to 10°, particularly preferably of 0°, to the circumferential direction, the incisions (3'') ending on both sides within the tread rib (1''). 11.Vehicle tire according to claim 10, characterized in that the incisions (3") have a length (cE) projected in the circumferential direction, relative to the incision center line (mE), of 10.0 mm to 30.0 mm, in particular of 15.0 mm to 25.0 mm.

12. Vehicle tire according to one of claims 3 to 11, characterized in that the groups (G, G', G'') include groups (G, G', G'') in which the incisions (3, 3', 3'') are symmetrical with respect to a line (LS) running parallel to the incision center lines (mE) of the incisions (3, 3', 3'') in plan view.

13. Vehicle tire according to one of claims 3 to 12, characterized in that the groups (G, G', G'') include groups (G, G', G'') in which the angles (β) at which the incisions (3, 3', 3'') extend to the radial direction, viewed in a cross-section extending perpendicular to the incision center line (mE) in plan view, are the same.Vehicle tire according to one of claims 1 to 13, characterized in that the angle (β) at which the cuts (3, 3', 3'') are arranged in plan view. 202301041 16 viewed in a cross-section perpendicular to the incision center line (mE), to the radial direction, is 15° to 40°, in particular 20° to 35°, preferably 25° to 30°.

Images