Vehicle tires

Abstract

Vehicle tires with a tread having circumferential grooves (2) designed to the intended tread depth (t1), which have two groove flanks (4, 5) and a groove base (6), wherein in at least one circumferential groove (2) elongated projections (7) are formed connected to the groove flanks (4, 5) and the groove base (6), the highest points of which are located at a depth (t2) of 30% to 70% of the tread depth and which each have a top surface (7a), to which a front surface (7b) is connected in the circumferential direction and a side surface (7c) is connected in the direction of the circumferential groove, which surfaces slope down to a groove path base (8) of a groove path (9) located at the level of the groove base (6), which has a width (b3) that is less than the width (b2) of the groove base (6) located outside the projections (7). The projections (7) on the two groove flanks (4, 5) are arranged in pairs opposite each other, are designed to be identical or largely identical and have a trapezoidal or trapezoidal top surface (7a).

Description

[0001] The invention relates to a vehicle tire with a tread having circumferential grooves designed to the intended tread depth, which have two groove flanks and a groove base, wherein in at least one circumferential groove, circumferentially elongated projections are formed connected to the groove flanks and the groove base, the highest points of which are located at a depth of 30% to 70% of the tread depth and which each have a cover surface extending along the groove flank, to which an end surface is connected in the circumferential direction and a flank surface is connected in the direction of the circumferential groove, wherein the end surfaces and the flank surfaces slope down to a groove path base of a groove path located at the level of the groove base, which has a width that is less than the width of the groove base located outside the projections.

[0002] Such a vehicle tire is known, for example, from DE 10 2019 207 297 A1. This vehicle tire has a tread with at least one circumferential groove, to the groove flanks and simultaneously to the groove base of which projections are attached, each of which is elongated in the circumferential direction. Each projection attached to one groove flank, together with a projection attached to the other groove flank and adjoining it in the circumferential direction, forms a pair of projections. Circumferentially successive pairs of projections have mutual spacings of 15.00 mm to 60.00 mm. Circumferential grooves designed in this way are provided, in particular, between a shoulder rib and a central tread rib.This is intended to positively influence the tire's handling characteristics, counteracting deformation of the shoulder-side tread rib during cornering by having the groove flanks of the shoulder-side circumferential groove brace against the projections. Furthermore, the projections belonging to the same pair can brace against each other under circumferential traction and braking loads, thus stabilizing the shoulder-side and central tread ribs. EP 2 292 448 A1 discloses a commercial vehicle tire with a tread featuring wide circumferential grooves that run straight along the tread periphery and whose groove base has a zigzag pattern, characterized by a circumferentially extending row of raised protrusions on each of the two flanks of the circumferential groove, which project pyramidally from the groove flanks.The zigzag shape of the groove base results from the projections on one side of the groove being offset circumferentially from those on the opposite side. This particular design of the projections on the groove sides is intended to prevent stones from becoming wedged in the circumferential grooves.

[0003] The invention is based on the objective of designing circumferential grooves with projections on the groove flanks in the tread of a vehicle tire of the type mentioned above in such a way that the jamming of stones is particularly effectively prevented and good wet performance and traction performance are maintained or restored as the tread wears down.

[0004] The problem set out in the invention is solved by the fact that the projections on the two groove flanks are arranged in pairs opposite each other, are designed to be identical or largely identical and have a trapezoidal or trapezoidal top surface.

[0005] The two opposing protrusions ensure particularly effective ejection of intruding stones, thus preventing them from becoming jammed. As the tread wears down, the edges of the top surfaces reach or approach the tread periphery, ensuring good traction and wet-weather performance, the latter in conjunction with the grooved path between the protrusions.

[0006] According to a preferred embodiment, the top surfaces of the two projections slope radially at an angle of 40° to 70° to the groove bed. In this way, the edges of the top surfaces can ensure particularly effective traction performance from a certain level of tread wear.

[0007] In another preferred embodiment, the cover surfaces are each bounded by a longer and a shorter longitudinal side as well as by two end faces, with the cover surfaces abutting the groove flanks with their longer longitudinal sides. This design is advantageous for the stability of the groove flanks.

[0008] In another preferred embodiment, the end faces of the cover surfaces form an acute angle of 30° to 50° with the longer longitudinal side of the cover surfaces. This measure also ensures particularly effective gripping edges as the tread wears down.

[0009] For the wet performance of the tread, it is also advantageous if the groove path formed between the flank surfaces of the projections has a particularly constant width of 1.50 mm to 5.00 mm, whereby this width is at least 1.00 mm less than the width of the groove base outside the projections.

[0010] The projections advantageously have a length along the groove flanks of 15.00 mm to 60.00 mm. Shorter projections are typically found in the circumferential grooves of treads for passenger cars, longer projections in the treads of tires for commercial vehicles.

[0011] For the aforementioned grip properties, it is also advantageous if the shorter longitudinal side of the cover surfaces has an extent length that is 50% to 70% of the extent length of the longer longitudinal side.

[0012] For the stability of the projections, it is also advantageous if the end faces and the flank faces of the projections run in a radial direction or at an angle of up to 10° to the radial direction, in the latter case sloping down towards the bottom of the groove.

[0013] Further features, advantages, and details of the invention will now be described in more detail with reference to the drawing, which schematically depicts an embodiment of the invention. The drawing shows Fig. 1 a top view of a section of a tread of a vehicle tire with an embodiment of the invention, Fig. 2 a cut along line II-II of the Fig. 1 and Fig. 3 a slant view according to the in Fig. 1. Direction of view indicated by an arrow P3.

[0014] Vehicle tires designed according to the invention are tires for motor vehicles, in particular for multi-track motor vehicles such as trucks, buses, passenger cars, vans (transporters, light trucks), or SUVs. The vehicle tire is preferably a pneumatic tire, especially of radial construction. Tires designed according to the invention can have the usual structure of vehicle tires for the respective application. This structure is therefore neither shown nor described.

[0015] Fig. Figure 1 shows a top view of a section 1 of a tread of a vehicle tire, showing only a narrow circumferential segment of the tread with a section of a circumferential groove 2 arranged in a zigzag pattern. The tread may contain several circumferential grooves 2 at the usual intervals, for example, two to five circumferential grooves 2. Circumferential grooves 2 may also be combined with other circumferential grooves, as well as with transverse grooves, cuts, and the like, and the tread may also have tread blocks or be structured in a tread block manner.

[0016] According to the in Fig. 1 and in Fig. In the section shown in Figure 3, the circumferential groove 2 is composed of groove sections 3 in the circumferential direction, such that successive groove sections 3, while otherwise largely identical in design, are inclined in the opposite direction to the circumferential direction, with the angle in this respect being ≤ 30°. Within each groove section 3, the circumferential groove 2, outside of a central section in which, as will be described below, projections 7 are formed, is bounded by two groove flanks 4 and 5 and by a groove base 6, which connects to the two groove flanks 4, 5 via transition radii 6a. Each groove flank 4, 5 runs at an angle α of 3° to 20° to the radial direction and such that the circumferential groove 2 has a width that increases from the groove base 6 towards the periphery of the tread.

[0017] At the tread periphery, the circumferential groove 2 has a width b1, which is determined between the edge edges of the circumferential groove 2 and is between 7.00 mm and 22.00 mm, depending, for example, on whether it is a passenger car tire or a commercial vehicle tire, wherein the width b1 is preferably constant and the same in all groove sections 3. In the area of ​​the groove base 6, the circumferential groove 2 has a width b2, which is determined between the radially inner ends of the groove flanks 4, 5 and is between 3.00 mm and 6.00 mm. In the illustrated embodiment, the groove flanks 4, 5 are designed such that the angle α of one groove flank 4 increases continuously and slightly from one end of the groove section 3 to the other end of the groove section 3, while the angle α of the opposite groove flank 5 changes in the opposite direction.

[0018] The groove sections 3 have a length I1 of 30.00 mm to 80.00 mm. For example Fig. 2 shows that the circumferential groove 2 also has a depth t1 which corresponds to the respective intended tread depth and is in particular 6.5 mm to 60.00 mm, depending on the type of tire - for example a passenger car tire or a commercial vehicle tire.

[0019] How in particular Fig. 1 and Fig. As shown in Figure 3, the projections 7 in the middle section of each groove section 3 are connected to the groove base 6 and to one groove flank 4 and 5 respectively. The projection 7 connected to groove flank 4 is located directly opposite the projection 7 connected to the other groove flank 5. The two projections 7 are largely or even identical in shape. As shown in particular Fig.As shown in Figure 2, the projections 7 begin on the groove flanks 4, 5 at a depth t2 of 30% to 70% of the profile depth t1 and are bounded here by a trapezoidal or trapezoidal cover surface 7a extending along the circumference of the groove flanks 4, 5. This cover surface slopes downwards at an angle β of 40° to 70° to the radial direction and towards the groove base 6. The cover surface 7a is bounded by a longer longitudinal side 7a1, a shorter longitudinal side 7a2 running parallel or nearly parallel to it, and two end faces 7b1. The longer longitudinal sides 7a1 of the cover surfaces 7a are located on the groove flanks 4, 5.

[0020] The two end faces 7b1 of the top surface 7a, which connect the longitudinal sides 7a1, 7a2, each form an acute angle γ of 30° to 50° with the longer longitudinal side 7a1. End faces 7b adjoin the end faces 7b1, and a flank surface 7c adjoins the shorter side 7a2 of the top surface 7a. In a preferred embodiment, the two end faces 7b and the flank surfaces 7c of the projections 7 extend radially or at an angle of up to 10° to the radial direction and such that they slope down to a rounded groove path base 8 of a groove path 9 between the flank surfaces 7c.

[0021] The groove path 9 formed between the flank surfaces 7c has a particularly constant width b3 of 1.50 mm to 5.00 mm and is at least 1.00 mm less than the width b2 of the groove base 6. Its base 8 is located at the level of the groove base 6. The projections 7 have an extent length I2 corresponding to the length of the longer longitudinal side 7a1 of the cover surface 7, which is 15.00 mm to 60.00 mm. The shorter longitudinal sides 7a2 of the cover surfaces 7a have an extent length I3, which is 50% to 70% of the extent length I2 of the longer longitudinal side 7a1.

[0022] In an alternative embodiment, the groove flanks 4, 5 are designed such that they each run at the same angle of inclination relative to the radial direction along their longitudinal extent. In another alternative embodiment, the circumferential grooves 2 are straight circumferential grooves. The opposing pairs of projections are distributed around the circumference at intervals between them.

[0023] On new, unworn tires, the protrusions 7 act as stone ejectors. As the tread wears down, further beneficial effects of the protrusions come into play, namely through their edges, which are then located at or near the tread periphery, in particular their beneficial influence on wet grip and traction performance. Reference symbol list 1 Section of the tread 2 circumferential grooves 3 groove section 4, 5 groove flank 6 groove base 6a Transitional rounding 7 lead 7a Cover area 7b Front surface 7c Flank surface 7a1, 7a2 Long side 7b1 Front 8 Grooved path base 9 groove path α angle (groove flanks) β angle (cover surface 7) γ Angle (7a1, 7b1) I1 Extension length (groove section 3) I2 Extension length (projection 7) I3 Extension length (longitudinal side 7a2) b1 Width (circumferential groove 2) b2 Width (groove base 6) b3 Width (Groove path 9) t1 profile depth t2 depth (protrusion 7) QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] DE 10 2019 207 297 A1

[0002] EP 2 292 448 A1

[0002]

Claims

[1] Vehicle tires with a tread having circumferential grooves (2) designed to the intended tread depth (t1), which have two groove flanks (4, 5) and a groove base (6), wherein in at least one circumferential groove (2) elongated projections (7) are formed connected to the groove flanks (4, 5) and the groove base (6), the highest points of which are located at a depth (t2) of 30% to 70% of the tread depth and which each have a cover surface (7a) extending along the groove flank (4, 5), to which a front surface (7b) adjoins in the circumferential direction and a side surface (7c) adjoins in the direction of the circumferential groove, wherein the front surfaces (7b) and the side surfaces (7c) slope down to a groove path base (8) of a groove path (9) located at the level of the groove base (6), which has a width (b3) exhibits a width (b2) of the groove base (6) outside the projections (7), characterized by, that the projections (7) on the two groove flanks (4, 5) are opposite each other in pairs, are designed to be identical or largely identical and have a trapezoidal or trapezoidal top surface (7a). [2] Vehicle tires according to claim 1, characterized by , that the top surfaces (7a) of the two projections (7) slope down at an angle (β) of 40° to 70° to the groove path base (8) in the radial direction. [3] Vehicle tires according to claim 1 or 2, characterized by , that the cover surfaces (7a) are each bounded by a longer and a shorter longitudinal side (7a1, 7a2) and by two end faces (7b1), wherein the cover surfaces (7a) with their longer longitudinal sides (7a1) connect to the groove flanks (4, 5). [4] Vehicle tires according to any one of claims 1 to 3, characterized by, that the end faces (7b1) of the top surfaces (7a) with the longer longitudinal side (7a1) of the top surfaces (7a) each enclose an acute angle (γ) of 30° to 50°. [5] Vehicle tires according to any one of claims 1 to 4, characterized by , that the groove path (9) formed between the flank surfaces (7c) of the projections (7) has a particularly constant width (b3) of 1.50 mm to 5.00 mm, wherein this width is at least 1.00 mm less than the width (b2) of the groove base (6) outside the projections (7). [6] Vehicle tires according to any one of claims 1 to 5, characterized by , that the projections (7) along the groove flanks (4, 5) have an extent length (I2) which is 15.00 mm to 60.00 mm. [7] Vehicle tires according to any one of claims 1 to 6, characterized by , that the shorter longitudinal side of the cover surfaces (7a) has an extent length (I3) which is 50% to 70% of the extent length (I2) of the longer longitudinal side (7a1). [8] Vehicle tires according to any one of claims 1 to 6, characterized by , that the end faces (7b) and the flank faces (7c) of the projections (7) extend in a radial direction or at an angle of up to 10° to the radial direction.

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