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EP-4516533-B1 - VEHICLE TYRE

EP4516533B1EP 4516533 B1EP4516533 B1EP 4516533B1EP-4516533-B1

Inventors

  • Özüduru, Ahmet
  • SOYYUECE, ATAKAN
  • Ecke, Stefan

Dates

Publication Date
20260513
Application Date
20240807

Claims (13)

  1. Vehicle tyre (2) having a tread (1), wherein the tread (1) has at least one profile-block row (P; 4, 6) which extends in a circumferential direction (U), wherein the at least one profile-block row (P; 4, 6) is subdivided into multiple profile blocks (PB; 4a, 6a) by transverse channels (R; 7, 8), wherein the transverse channels (R; 7, 8) each extend in a direction of extent (E) at an angle to a transverse direction (Q), wherein an elevation (11) made up of at least two elevation parts (11a, 11b, 11c) is arranged in the respective transverse channel (R; 7, 8), wherein a channel depth (T) of a channel bottom (9c) of the respective transverse channel (R; 7, 8) is reduced in relation to a base depth (T0) of the respective transverse channel (R; 7, 8) in the region of the elevation (11), wherein the elevation (11) is cut in the direction of extent (E) of the respective transverse channel (R; 7, 8) such that a lamella (13) with a lamella bottom (13c) at a lamella-bottom depth (T13) is formed, wherein the lamella (13) extends in the direction of extent (E) over all the elevation parts (11a, 11b, 11c) of the elevation (11), characterized in that the elevation (11) has in the direction of extent (E) of the respective transverse channel (R; 7, 8) at least a tread-inner-side elevation part (11a), with a horizontally extending tread-inner-side top surface (14a), a middle elevation part (11b), with a horizontally extending middle top surface (14b), and a tread-outer-side elevation part (11c), with a horizontally extending tread-outer-side top surface (14c), and wherein - a tread-inner-side channel depth (Ta) is obtained above the tread-inner-side elevation part (11a), - a middle channel depth (Tb) is obtained above the middle elevation part (11b), and - a tread-outer-side channel depth (Tc) is obtained above the tread-outer-side elevation part (11c), wherein the tread-inner-side channel depth (Ta), the middle channel depth (Tb) and the tread-outer-side channel depth (Tc) are each smaller than the base depth (T0) of the respective transverse channel (R; 7, 8), and wherein the middle channel depth (Tb) is smaller than the tread-inner-side channel depth (Ta) and the tread-outer-side channel depth (Tc) such that a descending flank and an ascending flank are formed on both sides of the middle elevation part (11b) so as to obtain a channel bottom (9c) having multiple steps.
  2. Vehicle tyre (2) according to Claim 1, characterized in that the lamella bottom (13c) extends at a constant lamella-bottom depth (T13) over all the elevation parts (11a, 11b, 11c).
  3. Vehicle tyre (2) according to Claim 1 or 2, characterized in that the lamella-bottom depth (T13) of the lamella bottom (13c) corresponds to at least 80% of the base depth (T0), preferably at least 90% of the base depth (T0), in particular is identical to the base depth (T0).
  4. Vehicle tyre (2) according to Claim 3, characterized in that the base depth (T0) corresponds to between 60% and 100%, preferably between 70% and 80%, of a full profile depth (T*) of the tread (1).
  5. Vehicle tyre (2) according to one of the preceding claims, characterized in that the lamella (13) splits the elevation (11) centrally.
  6. Vehicle tyre (2) according to one of the preceding claims, characterized in that a lamella width (B13) of the lamella (13) is between 0.5 mm and 2 mm, preferably between 0.6 mm and 0.8 mm.
  7. Vehicle tyre (2) according to one of the preceding claims, characterized in that the tread-inner-side channel depth (Ta) and the tread-outer-side channel depth (Tc) are identical.
  8. Vehicle tyre (2) according to one of the preceding claims, characterized in that groove-like depressions (12a, 12b, 12c) that in each case extend in the circumferential direction (U) are formed between the individual elevation parts (11a, 11b, 11c) of the elevation (11) in the direction of extent (E).
  9. Vehicle tyre (2) according to one of the preceding claims, characterized in that the lamella (13) is delimited in the circumferential direction (U) by parallel lamella side walls (13a, 13b) which extend in the direction of extent (E) of the respective transverse channel (R; 7, 8) over all the elevation parts (11a, 11b, 11c), wherein the lamella side walls (13a, 13b) are non-planar and formed to be three-dimensionally recessed and projecting.
  10. Vehicle tyre (2) according to Claim 9, characterized in that the lamella side walls (13a, 13b) are formed to be three-dimensionally recessed and projecting in a repeated manner.
  11. Vehicle tyre (2) according to one of the preceding claims, characterized in that the transverse channels (R; 7, 8) each extend in the direction of extent (E), preferably parallel to one another, at an angle of between 30° and 55° to the transverse direction (Q).
  12. Vehicle tyre (2) according to one of the preceding claims, characterized in that the channel bottom (9c) of the respective transverse channel extends at the base depth (T0) next to the elevation (11) in the direction of extent (E), in particular in the shoulder-outer-side direction.
  13. Vehicle tyre (2) according to one of the preceding claims, characterized in that the profile-block row (PB) is a middle profile-block row (4) and the transverse channels are middle transverse channels (7), wherein the tread (1) has at least one central circumferential channel (3) and shoulder-side circumferential channels (5), wherein the shoulder-side circumferential channels (5) extend so as to be offset from the at least one central circumferential channel (3) on either side in the transverse direction (Q), wherein the at least one central circumferential channel (3) extends in the circumferential direction (U) adjacent to an equatorial plane of the vehicle tyre (2), and between the at least one central circumferential channel (3) and the respective shoulder-side circumferential channel (5) there is arranged the respective middle profile-block row (4) extending in the circumferential direction (U), wherein the respective middle profile-block row (4) is subdivided into middle profile blocks (4a) by the middle transverse channels (7), wherein the middle transverse channels (7) each extend in the direction of extent (E) at an angle to the transverse direction (Q) and each open out at a central-side end (7a) into the at least one central circumferential channel (3) and open out at a shoulder-side end (7b) into the respective shoulder-side circumferential channel (5), wherein the cut-in elevation (11) made up of the multiple elevation parts (11a, 11b, 11c) with the lamella (13) is arranged in the respective middle transverse channel (7), wherein the channel depth (T) of the channel bottom (9c) of the middle transverse channel (7) is reduced in relation to the base depth (T0) of the middle transverse channel (7) in the region of the elevation (11), wherein the elevation (11) is arranged in a central-side end region (10a) of the middle transverse channel (7), and the central-side end region (10a) adjoins the central-side end (7a) of the middle transverse channel (7).

Description

The invention relates to a vehicle tire according to the preamble of claim 1. Vehicle tires, especially pneumatic tires, conventionally feature circumferential rows of tread blocks separated by several circumferential grooves (central groove, shoulder grooves). Transverse grooves, such as V-shaped or angled grooves, open into these circumferential grooves, further subdividing the rows of tread blocks into individual tread blocks. This creates a specific tire tread pattern. For good snow performance of a tire tread, two properties are particularly important: Firstly, snow-snow friction, i.e., friction between the snow held in the tire tread and the snow layer on the road surface, and secondly, the leading edge of a tread block (leading block edge of a tread block), which rotates into the tire contact patch during operation of the vehicle tire. For both properties, it is advantageous if the lateral grooves open wide when turning into the tire contact patch. This allows the incoming block edge to offer better milling performance due to a larger clearance angle. Furthermore, a wider lateral groove allows more snow to be collected in the respective groove, thus improving snow-on-snow friction. In DE 10 2019 217 439 A1 It is described to arrange base elevations (raised areas, "tie-bar") of varying depth or height in the transverse grooves, through which The groove depth of the transverse grooves is locally reduced. In each of the base raised sections, two grooves, separated by a rib, are formed on a top surface, parallel to each other and spaced at the same intervals as the groove flanks of the respective transverse groove. These grooves serve as additional snow pockets and provide extra gripping edges. When driving on snow or slush, snow can be pressed into and compacted in the grooves, resulting in improved traction. Additional circumferentially extending depressions adjacent to the base raised sections form further snow pockets to enhance the effect of snow-on-snow friction. A disadvantage of this design is that the transverse grooves are only superficially formed in the respective base section. While the base section, which connects the two central or shoulder-side profile blocks adjacent to the transverse groove in the direction of travel, even across the groove base, does increase profile stiffness (e.g., for dry braking), it also prevents the transverse groove from opening wide. This reduces the clearance angle of the incoming profile block edge and results in poorer milling performance. Furthermore, the reduced opening of the transverse groove means less snow can be collected, thus impairing the snow-on-snow friction effect. In US 11,161,375 B2 The design features a connecting rib with a lamellar incision, which is located only in the central area of the transverse grooves that open into one of the central circumferential grooves. In the transverse grooves that open into one of the shoulder-side circumferential grooves, the connecting rib with the lamellar incision can also be located in an end region of the respective transverse groove adjacent to the shoulder-side circumferential groove. The lamellar incision of the connecting ribs in the transverse grooves, in conjunction with other specially arranged features, ensures a secure connection. Lamellar incisions in the profile blocks maintain a good balance between steering stability on dry roads and behavior on snow and ice. DE 10 2015 214 483 A1 This describes a vehicle tire with a shoulder-side row of tread blocks, which is bordered on the inside of the tread by a shoulder-side circumferential groove. Transverse grooves, running essentially parallel to each other, open into the shoulder-side circumferential groove, each of which is bounded by a groove base and two groove flanks. Each of these transverse grooves has at least two adjacent groove sections of different depths within the contact patch, with the depth of the groove sections increasing stepwise towards the edge of the tread. This is intended to reduce air pumping noise, which is generated in the shoulder-side areas of the tread by air being forced through the transverse grooves. Reducing air pump noise is achieved in EP 2 660 078 B1 This is achieved by incorporating tie bars with lamellar-like fine cuts or notches in the transverse grooves that merge into the shoulder-side circumferential grooves. This allows the transverse groove to open up in front of the shoulder-side circumferential grooves, enabling air to escape from the transverse grooves. Furthermore, the portion of the transverse grooves merging into the central circumferential groove is narrowed, preventing the formation of snow pockets or similar features between the tread blocks. Therefore, this tire offers no improvement in snow-on-snow friction. In DE 10 2005 013 810 A1 A vehicle tire is described which has a connecting rib in each of its transverse grooves that merge into circumferential grooves on the shoulder side. This conn