Vehicle tires

Abstract

Vehicle tyre with a tread with circumferentially running rows of tread blocks or tread block-like structured tread ribs, which have a minimum width (B) of 35.00 mm, are laterally delimited by circumferential grooves and are each provided with a plurality of incisions extending parallel to one another and in the axial direction, passing through the respective tread element, wherein each incision (4, 4') has two central sections (6a, 6b) and two edge sections (8a, 8b) which are shallower than the central sections (6a, 6b), of which one edge section (8b) has a smaller depth (t 8b ) than the other edge section (8a) and wherein between the central sections (6a, 6b) a base elevation (7) is formed which connects the two incision walls (5) to one another and starts from the incision base. In profile elements, successive incisions (4, 4') are present in the circumferential direction, in which the positions of the deeper and shallower edge sections (8a, 8b) alternate from incision (4) to incision (4'), whereby the base elevations (7) are arranged relative to the cross-sectional center plane (E Q ) of the incisions (4, 4') are each offset in the direction of the deeper edge section (8a).

Description

[0001] The invention relates to a vehicle tire with a tread with circumferentially running rows of profile blocks or profile block-like structured profile ribs, which have a minimum width of 35.00 mm, are laterally delimited by circumferential grooves and are each provided with a plurality of transverse cuts extending parallel to one another and in the axial direction, having a constant width of 0.40 mm to 1.20 mm and two cut walls each, wherein each cut has two central sections and two edge sections which are shallower than the central sections, wherein one edge section has a smaller depth than the other edge section and wherein in the central region of the cuts, between the central sections, a central base elevation is formed which connects the two cut walls to one another and starts from the cut base.

[0002] Such a vehicle tire is in accordance with the embodiment Fig. 7 of EP 3 659 825 A1. The two central sections and the edge sections of the incisions have identical extension lengths, with the base elevation being formed at the cross-sectional center plane of the incisions and the central sections extending symmetrically with respect to the cross-sectional center plane.

[0003] In such tread block rows or tread block-like ribs with an axial width of at least 35.00 mm, the traversing sipes also have a correspondingly large axial extension. The base elevations in the sipe centers ensure that the stiffness differences between the edge areas of the sipes and the central areas are somewhat balanced. This measure is intended to improve the tire's wear pattern and handling characteristics on dry surfaces while maintaining acceptable snow performance.In the circumferentially successive incisions, the central base elevations, which are also aligned in the circumferential direction, are located on a circumferential line, whereby the rigidity of the tread block row or tread block-like structured tread rib is increased in the central area, so that the tread block row or tread block-like structured tread rib wears unevenly and to an increased extent.

[0004] The invention is therefore based on the object of achieving a stiffness distribution in a vehicle tire of the type mentioned at the outset in profile block rows or profile block-like structured profile ribs with cuts with base elevations in the central cut area, with which a uniform abrasion behavior can be achieved.

[0005] The object is achieved according to the invention in that in the circumferentially successive incisions the positions of the deeper and shallower edge sections alternate from incision to incision, wherein the central base elevations are offset from the cross-sectional center plane of the incisions in the direction of the deeper edge section.

[0006] According to the invention, the deeper and shallower edge sections are therefore provided alternating left-right and right-left in the circumferential direction of successive incisions, and the central base elevation is located in one incision on one side of the cross-sectional center plane, closer to the deeper edge section, and in the other successive incision on the other side of the cross-sectional center plane and likewise facing the deeper edge section. In this way, the longitudinal and transverse stiffness of the relevant row of profile blocks or of the block-like structured profile rib can be influenced in such a way that a uniform stiffness distribution and thus uniform abrasion behavior is achieved. This design is particularly advantageous for profile blocks and profile block-like profile structures or profile ribs that have a larger axial width of, for example, 35.00 mm or more.

[0007] In a preferred embodiment, the central base elevations, which are offset from the cross-sectional center plane of the incisions in the direction of the deeper edge section, directly adjoin the cross-sectional center plane. This design is particularly advantageous for tread blocks or tread block-like tread structures or tread ribs that are laterally bordered by circumferential grooves and have an axial width of at least 35.00 mm, ensuring a uniform stiffness distribution and thus uniform wear behavior.

[0008] The height of the mean base elevations in the radial direction, measured from the base of the cuts, is also important for the uniform stiffness of the tread blocks or ribs. The mean base elevations therefore extend in the radial direction and from the base of the cuts to a height corresponding to 25% to 50% of the tread depth of the respective vehicle tire or tread. Along the base of the cuts, the length of the base elevations is 1.50 mm to 3.00 mm.

[0009] The stiffness distribution and thus the wear behavior are also influenced by the design of the edge sections. In this regard, it is particularly advantageous if the deeper edge sections have a depth that is 50% to 80% of the depth of the central sections, and if the shallower edge sections have a depth that is 15% to 45% of the depth of the central sections, with all depths being measured in the radial direction from the tread periphery.

[0010] The influence of the edge sections on the stiffness of the tread blocks or ribs, and thus on the abrasion behavior, also depends on their size in the direction of extension of the incisions. In this regard, it is preferred that the edge sections have lengths in the direction of extension of the incisions that preferably correspond and are between 3.00 mm and 6.00 mm, preferably in the order of 4.00 mm.

[0011] Furthermore, the central sections preferably have, in particular, constant and consistent depths of 65% to 100%, in particular of 65% to 90%, of the profile depth.

[0012] The central sections further preferably have extension lengths of 10.00 mm to 20.00 mm.

[0013] Profile elements, such as profile blocks or profile-block-like structures in the tread, each have at least two circumferentially successive cuts, in which the positions of the deeper and shallower edge sections alternate from cut to cut and are offset in the direction of the deeper edge section via respective base elevations above the cross-sectional center plane of the cuts. Depending on the design or external shape of the profile blocks or profile-block-like ribs, the number of such cuts can be up to eight, especially if these cuts do not differ from one another or differ only slightly in terms of their extension lengths due to the design of the profile blocks or profile ribs.

[0014] 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 view of profile blocks of a tread of a vehicle tire, Fig. 2 a section along the line II-II of the Fig. 1 and Fig. 3 a section along the line III-III of the Fig. 1.

[0015] Vehicle tires designed according to the invention are in particular pneumatic vehicle tires of radial design, furthermore tires for passenger cars, vans, transporters, SUVs, light trucks or commercial vehicles, preferably all-season tires or winter tires.

[0016] The term "extension length," for example of incisions or their sections, is understood to mean the length of a straight line connecting their ends. Incisions extending in the axial direction, as mentioned in claim 1, are understood to mean incisions in which a straight line connecting their ends runs in the axial direction with a deviation of up to ± 10°.

[0017] Fig. 1 shows four tread blocks 1, two of which each belong to tread block rows 1a running in the circumferential direction of a profiled tread of a vehicle tire. The two tread block rows 1a each have a width B of at least 35.00 mm at the tread periphery and at their narrowest points in the axial direction, are located in the middle region of the tread, and are therefore not shoulder-side tread block rows, although one of the two tread block rows 1a can be arranged along the central mid-circumferential line of the tread (the equatorial ridge of the tire). The two tread block rows 1a are separated from one another by a circumferential groove 2, and further circumferential grooves (not designated or shown) delimit the two tread block rows 1a on the outside. The double arrow U indicates the circumferential direction of the tread.

[0018] The circumferential groove 2 and the other circumferential grooves not shown have, in the radial direction, the tread depth T ( Fig. 2, Fig. 3), which, for example, is 6.50 mm to 9.00 mm for tires for passenger cars. Within the tread block rows 1a, successive tread blocks 1 in the circumferential direction are each separated from one another by a transverse groove 3, which in the schematic embodiment shown has a depth corresponding to the circumferential groove 2. In the embodiment shown, each tread block 1 is further provided with cuts 4, 4', which are arranged, for example, evenly distributed within each tread block 1, extend in the example in plan view straight and in the axial direction of the tread as well as parallel to one another and traverse the respective tread block 1. In the circumferential direction, a cut 4' follows a cut 4, so that with two cuts in a tread block 1, there is one cut 4 and one cut 4', with three cuts, as in Fig. 1, two incisions 4 or 4' and one incision 4 or 4', and in the case of four incisions, two incisions 4 and two incisions 4'. The incisions 4, 4' each have two opposing incision walls 5 and a constant width b1 of 0.40 mm to 1.20 mm, in particular up to 0.80 mm.

[0019] Fig. 2 shows a central, radial section along the incision center plane E4 of an incision 4 in the direction of the arrows indicating the section, Fig. Figure 3 shows a radial section along the incision center plane E4' of an incision 4' in the direction of the arrows indicating the section, the cutting direction in Fig. 3 with that in Fig. 2. The cuts in Fig. 2 and Fig. 3 show a view of one of the cut walls 5, with the second cut wall 5 being at a distance b1 from the cut wall 5 shown in the Fig. 2 and Fig. 3 shown incision wall 5.

[0020] How Fig. 2 and Fig. 3, each incision 4, 4' has two central sections 6a, 6b, each having a particularly constant incision depth t1 of 65% to 100%, in particular of 75% to 90%, of the profile depth T, and two edge sections 8a, 8b, with which the incisions 4, 4' open into circumferential grooves. The central sections 6a, 6b are separated from one another by a central base elevation 7 and, in particular, have different extension lengths L 6a and L 6b which, for profile blocks 1 in treads of tyres for passenger cars, are in the order of 10.00 mm to 20.00 mm.

[0021] The edge section 8a adjoins the central section 6a, and the edge section 8b adjoins the central section 6b. The edge sections 8a have a depth t in the radial direction. 8a the edge sections 8b have a depth t 8b , where the depth t 8a50% to 80% of the depth t1 of the central sections 6a, 6b and is greater than the depth t 8b , which is 15% to 45% of the depth t1 of the central sections 6a, 6b. In the embodiment shown, the edge sections 8a, 8b have matching axial extensions or, in the direction of extension of the incisions 4, 4', lengths l 8a , l 8b which preferably correspond and are in particular 3.00 mm to 6.00 mm, preferably in the order of 4.00 mm.

[0022] As mentioned, between the central sections 6a, 6b there is a central base elevation 7, which is preferably the only base elevation of the incisions 4, 4', connects the two incision walls 5 and extends in the radial direction from the base of the incision 4, 4' to a height h, which corresponds to 30% to 55% of the profile depth T and has a length L at the base of the incision Gfrom 1.50 mm to 3.00 mm. The incisions 4, 4' each have a cross-sectional center plane E Q which divides each notch 4, 4' into two halves of equal length. In the embodiment shown, each base elevation 7 is directly connected to the cross-sectional center plane E Q subsequently formed offset in the direction of the deeper edge section 8a.

[0023] The lengths L 6a , L 6b are defined as lengths of straight lines between intersections S1, S2 of straight lines along the base of the incision with straight lines along straight sections of the lateral flanks of the edge sections 8a, 8b and the central base elevation 7. Lengths l 8a , l 8b and L Gare lengths of straight lines along the outer side of the edge sections 8a, 8b up to their intersections S3 with the straight sections of the lateral flanks of the edge sections 8a, 8b. The length L G is the length of a straight line between the two intersection points S2 of the straight line along the base of the notch with straight lines along the straight sections of the lateral flanks of the base elevation 7.

[0024] As a comparison of the Fig. 2 and Fig. 3 shows, in the incision 4' the deeper edge section 8a is located to the left of the basic elevation 7, in the incision 4 to the right of the basic elevation 7. The incision 4' is thus, with otherwise identical design, lower than the incision 4 by a distance in the cross-sectional center plane E QThe radial axis is rotated by 180°. In the circumferentially alternating incisions 4, 4' of a profile block 1, the left-right positions of the edge sections 8a, 8b alternate, as do the left-right positions of the base elevations 7.

[0025] The figures show a simplified design of the incisions 4, 4'. In alternative embodiments, the incisions, in plan view, run at least in sections in a wave-like, zigzag-like, or stepped manner, possibly also curved overall, with the incision walls 5 following this course.

[0026] The edge sections 8a, 8b have different lengths l in alternative designs 8a and l 8b in the mentioned range of 3.00 mm to 6.00 mm. The base elevations 7 can be located at a distance from the cross-sectional center plane E Qof a few mm, in particular from 2.00 to 7.00 mm, determined as the length of a straight line between the cross-sectional center plane E Q and the interface S3 adjacent to it. List of reference symbols 1 profile block 1a profile block row 2 circumferential grooves 3 transverse grooves 4, 4' notch 5 cutting wall 6a, 6b central section 7 Basic increase 8a, 8b edge section b1 Width (cuts 4, 4') E4, E4' cutting center E Q Cross-sectional midplane B Width h Height (basic elevation 7) L 6a , L 6b Extension length (central sections 6a, 6b) l 8a , l 8b Extension length (edge ​​sections 6a, 6b) L G Length (basic elevation) t1 depth t 8a Depth (edge ​​section 8a) t 8b Depth (edge ​​section 8b) S1, S2, S3 interfaces T tread depth U Circumferential direction of the tread 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] EP 3 659 825 A1

[0002]

Claims

[1] Vehicle tyres with a tread with circumferentially encircling rows of tread blocks or tread block-like structured tread ribs, which have a minimum width of 35.00 mm, are laterally delimited by circumferential grooves and are each provided with a plurality of incisions (4, 4') extending parallel to one another and in the axial direction, traversing the respective tread element, having a constant width (b1) of 0.40 mm to 1.20 mm and each having two incision walls (5), each incision (4, 4') having two central sections (6a, 6b) and two edge sections (8a, 8b) which are shallower than the central sections (6a, 6b), of which one edge section (8b) has a smaller depth (t 8b) than the other edge section (8a) and wherein in the middle region of the incisions (4, 4') between the central sections (6a, 6b) there is formed a central base elevation (7) connecting the two incision walls (5) to one another and extending from the base of the incision, characterized by that in the circumferentially successive incisions (4, 4') the positions of the deeper and shallower edge sections (8a, 8b) alternate from incision (4) to incision (4'), the central base elevations (7) being arranged relative to the cross-sectional center plane (E Q ) of the incisions (4, 4') are each offset in the direction of the deeper edge section (8a). [2] Vehicle tyre according to claim 1, characterized by that the base elevations (7), which are opposite the cross-sectional center plane (E Q ) of the incisions (4, 4') are each offset in the direction of the deeper edge section (8a), directly adjacent to the cross-sectional center plane (E Q ) connect. [3] Vehicle tyre according to claim 1 or 2, characterized by that the central base elevations (7) extend in the radial direction and from the base of the cuts (4, 4') to a height (h) which corresponds to 30% to 55% of the profile depth (T) and extend at the cut base over a length (L G ) from 1.50 mm to 3.00 mm. [4] Vehicle tyre according to one of claims 1 to 3, characterized by that the deeper edge sections (8a) have a depth (t 8a ), which is 50% to 80% of the depth (t1) of the central sections (6a, 6b), and the shallower edge sections (8b) have a depth (t 8b ), which is 15% to 45% of the depth (t1) of the central sections (6a, 6b). [5] Vehicle tyre according to one of claims 1 to 4, characterized by that the edge sections (8a, 8b) in the direction of extension of the incisions (4, 4') have lengths (l 8a , l 8b), which preferably correspond and are 3.00 mm to 6.00 mm, preferably in the order of 4.00 mm. [6] Vehicle tyre according to one of claims 1 to 5, characterized by that the central sections (6a, 6b) have in particular constant and consistent depths (t1) of 65% to 100%, in particular of 75% to 90%, of the profile depth (T). [7] Vehicle tyre according to one of claims 1 to 6, characterized by that the central sections (6a, 6b) have extension lengths (L 6a , L 6b ) which are 10.00 mm to 20.00 mm. [8] Vehicle tyre according to one of claims 1 to 7, characterized bythat the tread comprises profile elements with two to eight circumferentially successive incisions (4, 4'), in which the positions of the deeper and shallower edge sections (8a, 8b) alternate from incision (4) to incision (4') and the respective mean base elevation (7) relative to the cross-sectional center plane (E Q ) of the incisions (4, 4') is offset in the direction of the deeper edge section (8b).

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