VEHICLE AIR TIRES

Description

[0001] The invention relates to a pneumatic vehicle tire, in particular a passenger car winter tire, with a tread having shoulder-side blocks arranged in the edge regions of the tread and extending in the axial direction, with block edges running predominantly parallel to one another, and with middle blocks having block edges running predominantly parallel to one another between the shoulder-side blocks arranged in one edge region of the tread and the shoulder-side blocks arranged in the other edge region of the tread, wherein the block edges of the middle blocks, which run predominantly parallel to one another, diverge at most by an angle of less than 30°, preferably less than 20°, and more preferably less than 10°, and the block edges of the shoulder-side blocks, which run predominantly parallel to one another, diverge by an angle of less than 30°, preferably less than 20°, and more preferably less than 10°,wherein the shoulder-side blocks and the middle blocks are each provided with at least two incisions which, in plan view, run parallel to one another and extend to the axial direction of the pneumatic vehicle tire with a deviation of less than 45° on the circumferential surface of the pneumatic vehicle tire, said incisions having a width of 0.4 mm to 0.8 mm and, at their deepest point, a depth of at least 50% of the tread depth, wherein the shoulder-side blocks and the middle blocks are each provided with a plurality of microgrooves with a width of 0.1 mm to 0.3 mm and a depth of 0.1 mm to 0.3 mm, wherein the microgrooves extend parallel to the incisions in plan view and without crossing, wherein the shoulder-side blocks are each provided with at least two transverse microgrooves which, in plan view, run parallel to one another and extend predominantly in the circumferential direction of the pneumatic vehicle tire, having a width of 0.2 mm to 0.6 mm and a depth of 0.6 mm to 3 mm.,

[0002] A pneumatic vehicle tire of the type mentioned above is known, for example, from WO 2022 / 100799 A1. This pneumatic vehicle tire has a tread with shoulder-side blocks and central blocks arranged in shoulder-side block rows. The blocks are each provided with cuts that, in plan view, run at an angle of up to 45° to the axial direction and have a width of 0.4 mm to 0.8 mm and a maximum depth (depth at the deepest point) of at least 50% of the tread depth. Furthermore, the blocks are each provided with microgrooves that extend parallel to the cuts in plan view, each with a width and depth of 0.2 mm to 0.7 mm. In one embodiment shown, two transverse microgrooves are also formed in the shoulder-side blocks, which run at an angle of 0° to 15° to the circumferential direction and each have a funnel-like widening at their end regions.The microgrooves are designed to ensure the drainage of the water film, while still providing good power transmission to the surface as well as good wet braking and snow grip. The funnel-shaped widening improves water absorption and drainage into the transverse grooves and acts as a small "snow traction pocket" when driving on snow, improving snow grip through the effect of snow-on-snow friction.

[0003] WO 2007 / 028438 A1 discloses a pneumatic vehicle tire with a tread having shoulder-side blocks and band-like connected, central blocks, wherein the blocks are each provided with cuts running at an angle of 0° (shoulder-side blocks) or approximately 30° (central blocks) to the axial direction, with a width of greater than 0.4 mm and at most 0.8 mm and a maximum depth of up to 100% of the tread depth. The blocks are further each provided with microgrooves extending, in plan view, parallel to the cuts, with a width of 0.1 mm to 0.4 mm, in particular up to 0.3 mm, and a depth of 10% to 90% of the tread depth. The tread depth is 7 mm to 8 mm, so that the depth of the microgrooves is 0.7 mm to 7.2 mm. The shoulder-side blocks are also each provided with one or more transverse microgrooves traversing in the circumferential direction.The center blocks each contain two pairs of circumferentially aligned transverse microgrooves. The pneumatic tire is designed to offer good grip on winter roads while maintaining braking and traction on both dry and wet roads.

[0004] WO 2019 / 001790 A1 discloses a pneumatic vehicle tire with a tread having shoulder blocks and center blocks, each having at least two cuts running parallel to one another in plan view, each having a width of 0.4 mm to 0.8 mm and a maximum depth of at least 50% of the tread depth. The shoulder blocks and the center blocks are further each provided with a plurality of microgrooves running parallel to the cuts in plan view, each having a width and depth of 0.2 mm to 0.5 mm. The cuts and microgrooves in the shoulder blocks run, in plan view, at least over most of their extent, in the form of adjoining trapezoids pointing alternately in one circumferential direction and the other. The cuts and microgrooves in the center blocks run in a wave-like or zigzag shape in plan view.The shoulder blocks are preferably equipped with transverse microgrooves that intersect the microgrooves and cuts. The tire should offer optimal winter driving characteristics and good power transmission to the ground.

[0005] Winter tires for cars are subject to conflicting requirements. They must provide good grip on black ice, for which large contact areas of the winter tire with the black ice are advantageous. They must also provide good grip on snow and roughened ice, which is achieved through structured contact surfaces formed by cuts in the blocks of the winter tires. However, such cuts reduce the contact area on black ice.

[0006] Against this background, the object of the invention is to design a car winter tire in such a way that, in addition to good grip on smooth ice, good grip on snow or roughened ice is also possible.

[0007] This object is achieved with a passenger car winter tire according to the features of patent claim 1. The subclaims relate to particularly expedient developments of the invention.

[0008] The shoulder-side blocks are arranged in the axial direction in the edge areas of the tread.

[0009] A top view is understood to be a vertical view of the tread or a section of the tread.

[0010] The middle blocks are each provided with at least two transverse micro-grooves with a width of 0.2 mm to 0.6 mm and a depth of 0.6 mm to 3 mm, which run parallel to each other in plan view and extend predominantly in the circumferential direction of the pneumatic vehicle tyre, wherein the distance between two transverse microgrooves in shoulder-side blocks is greater than 3 mm and less than 10 mm and wherein the distance between two transverse microgrooves in middle blocks is greater than 2 mm and less than 7 mm.

[0011] Because the cuts and microgrooves extend in the axial direction and the transverse microgrooves extend predominantly in the circumferential direction, the transverse microgrooves intersect with the cuts and microgrooves. This divides the blocks into sub-areas, each of which forms a particularly small contact surface that is particularly suitable for transferring forces into fine structures in the ground. On the other hand, the sub-areas are flexibly connected to neighboring sub-areas on the blocks, so that they remain in contact with fine structures for an extended period of time and can transfer forces, even in the event of increased slippage. This enables particularly good grip on snow and roughened ice. The microgrooves and the transverse microgrooves have a particularly narrow width, resulting in a large contact surface on smooth ice and enabling good grip.

[0012] The particularly small distance between the transverse microgrooves in the shoulder-side blocks creates particularly small partial areas, which allows forces to be transferred particularly well into fine structures of the subsoil.

[0013] The minimum spacing between the transverse microgrooves results in sub-areas that are sufficiently large and strong to efficiently transfer forces to the ground. Furthermore, this allows for a sufficient contact area between the vehicle tire and a smooth ice surface, as the area of ​​transverse microgrooves is kept to a minimum.

[0014] A preferred embodiment provides that the distance between two incisions in shoulder-side blocks and / or in middle blocks is less than 7 mm. A particularly small distance between the incisions creates particularly small partial areas, allowing forces to be transferred particularly effectively into fine structures in the subsurface.

[0015] A further preferred embodiment provides that the distance between two transverse microgrooves in shoulder-side blocks and / or in middle blocks is less than twice, preferably one and a half times, and more preferably, single the distance between two incisions. By approximating the distance between two transverse microgrooves to the distance between two incisions, the surface of the partial areas is approximated to a square. This enables particularly high force transmission both in the circumferential and axial directions of the vehicle tire. Furthermore, small partial areas are created with the smallest possible surface area of ​​the transverse microgrooves and incisions.

[0016] A further preferred embodiment provides that the incisions and microgrooves extend on the circumferential surface of the vehicle tire with a deviation of at most 30°, preferably at most 25°, particularly preferably at most 20°, and further preferably at most 5° from the axial direction of the pneumatic vehicle tire. Particularly preferably, the incisions and microgrooves are aligned in the axial direction of the pneumatic vehicle tire. Such an alignment of the incisions and microgrooves enables particularly high force transmission in the circumferential direction as well as in the axial direction on structured surfaces. Furthermore, small partial areas are enabled, whereby the contact area on smooth ice is reduced as little as possible by the length of the incisions and microgrooves.

[0017] A further preferred embodiment provides for an angle a of between 50° and 130°, preferably between 65° and 115°, and particularly preferably between 80° and 100°, to be formed between the incisions and the transverse microgrooves. An angle a of 90° between the incisions and the transverse microgrooves is particularly preferred. An angle a that is as close as possible to 90° allows for the smallest possible partial areas with the shortest possible incisions and transverse microgrooves. The contact area on smooth ice is increased.

[0018] Another preferred embodiment provides for the cuts to have a width of 0.5 mm to 0.6 mm and, at their deepest point, a depth of at least 70%. The described cuts allow sufficient flexibility for an optimal cutting angle on snow, as well as high edge pressure on both smooth and rough ice. This flexibility allows for good grip on rough ice by conforming to the surface. This is possible even when the profile is partially worn due to the great depth.

[0019] A further preferred embodiment provides that the shoulder-side blocks and the middle blocks are each divided into partial areas by the transverse microgrooves intersecting with the incisions and with the microgrooves, wherein the partial areas are flexibly connected to the blocks to adjacent partial areas, wherein the partial areas of the shoulder-side blocks have a size of less than 100 mm 2 , preferably less than 80 mm 2 , and more preferably less than 60 mm 2 , and the partial areas of the middle blocks have a size of less than 60 mm 2 , preferably less than 50 mm 2 , and more preferably less than 40 mm 2 . A size of the partial areas of at most 100 mm 2 , and preferably smaller, makes it possible to transmit a higher force particularly into fine structures, in particular roughened ice. Such partial areas reach recesses in these fine structures and, due to their flexible connection, can transmit force into this structure over a relatively long period of time.

[0020] A further preferred embodiment provides for the incisions to run sinusoidally and / or zigzag-shaped along the circumference of the tread, preferably with a bulge in the radial direction. The shape of the incisions results in an increased edge portion in the circumferential direction and increases grip on rough ice.

[0021] The invention permits numerous embodiments. To further clarify its basic principle, two of them are shown in the drawings and are described below. These show in Fig. 1 a plan view of a center block of a pneumatic vehicle tire; Fig. 2 a plan view of a shoulder-side block of a pneumatic vehicle tire.

[0022] Figure 1shows a plan view of a central block 1 of a pneumatic vehicle tire with a nearly square surface defined by block edges 2, wherein the surface has incisions 3. The incisions 3 extend in a zigzag shape along the circumferential surface of the tire, i.e., in the circumferential direction as well as in the axial direction of the tire. Furthermore, the incisions 3 have a zigzag geometry in the radial direction of the tire. The incisions 3 each extend to the block edges 2 of the block 1 and are essentially parallel to one another. Microgrooves 4, arranged predominantly parallel and alternating with the incisions 3, also extend in a straight line to the block edges 2 of the central block 1. The microgrooves 4 are spaced apart from the incisions 3 and do not intersect them. On the circumferential surface, transverse microgrooves 5 run almost perpendicular to the microgrooves 4.The transverse microgrooves 5 run linearly across the central block 1 and end at a distance from the block edges 2 of the central block 1 that corresponds to three times the width of the transverse microgroove 5. The transverse microgrooves 5 intersect the microgrooves 4 and the incisions 3 at an angle a, thereby creating partial surfaces that are connected to the central block 1 independently of one another and flexibly to one another.

[0023] In Figure 21 shows a plan view of a shoulder-side block 6 of a pneumatic vehicle tire, which has an elongated surface geometry tapering to a point on one side. The shoulder-side block 6 has two parallel incisions 3 that run in a zigzag pattern on the circumferential surface and in the radial direction of the tire. A microgroove 4 runs predominantly parallel and straight between the incisions 3 and is spaced apart from the incisions 3. The incisions 3 and the microgroove 4 run from a block edge 2 of the shoulder-side block 6, the tapered edge, predominantly parallel to the longer block edges 2 of the shoulder-side block 6 and end at a distance from the opposite block edge 2 of the shoulder-side block 6. The incisions 3 and the microgroove 4 extend over approximately three-quarters of the width of the shoulder-side block 6.On the circumferential surface, transverse microgrooves 5 run almost perpendicular to microgroove 4 and almost perpendicular to incisions 3. The four transverse microgrooves 5 end at a distance from the block edges 2 of the shoulder-side block 6 that corresponds to three times the width of the transverse microgrooves 5. The transverse microgrooves 5 are spaced apart from one another on the tapered half of the shoulder-side block 6. The transverse microgrooves 5 cross incisions 3 and microgroove 4, creating partial surfaces that are connected to the shoulder-side block 6 independently of one another and flexibly to one another.

[0024] The partial surfaces created by the transverse microgrooves 5 and the incisions 3, as well as the microgrooves 4, are arranged at the tapered end of the shoulder-side block 6, with this end facing the central region of the tire tread. Thus, the partial surfaces in the central region of the tire tread enable greater power transmission from the tire to the ground on ice or snow. The edge region of the tire tread has no partial surfaces and deforms only slightly when cornering, thus enabling good power transmission when cornering, especially on surfaces with good grip. List of reference symbols

[0025] 1 middle block 2 block edge 3 cut 4 micro groove 5 transverse micro groove 6 shoulder-side block angle

Claims

1. Pneumatic vehicle tyre, in particular a winter car tyre, with a tread having shoulder-side blocks (6), which are arranged in the peripheral regions of the tread, extend in the axial direction and have block edges (2) running substantially parallel to one another, and having central blocks (1) with block edges (2) running substantially parallel to one another between the shoulder-side blocks (6) arranged in the one peripheral region of the tread and the shoulder-side blocks (6) arranged in the other peripheral region of the tread, the block edges (2) of the central blocks (1) that run substantially parallel to one another diverging at most by an angle of less than 30°, preferably less than 20°, and more preferably less than 10°, and the block edges (2) of the shoulder-side blocks (6) that run substantially parallel to one another diverging by an angle of less than 30°, preferably less than 20°, and more preferably less than 10°, the shoulder-side blocks (6) and the central blocks (1) being provided in each case with at least two sipes (3), which run parallel to one another in plan view, extend on the circumferential surface of the pneumatic vehicle tyre with a deviation of less than 45° in relation to the axial direction of the pneumatic vehicle tyre and have a width of 0.4 mm to 0.8 mm and a depth at their deepest point of at least 50% of the profile depth, the shoulder-side blocks (6) and the central blocks (1) being provided in each case with multiple micro grooves (4) with a width of 0.1 mm to 0.3 mm and a depth of 0.1 mm to 0.3 mm, the micro grooves (4) extending in plan view parallel to the sipes (3) and without crossing, the shoulder-side blocks (6) being provided in each case with at least two transverse micro grooves (5), which run parallel to one another in plan view, extend substantially in the circumferential surface of the pneumatic vehicle tyre and have a width of 0.2 mm to 0.6 mm and a depth of 0.6 mm to 3 mm, characterized in that the central blocks (1) are provided in each case with at least two transverse micro grooves (5), which run parallel to one another in plan view, extend substantially in the circumferential surface of the pneumatic vehicle tyre and have a width of 0.2 mm to 0.6 mm and a depth of 0.6 mm to 3 mm, the distance between two transverse micro grooves (5) in shoulder-side blocks (6) being greater than 3 mm and less than 10 mm and the distance between two transverse micro grooves (5) in central blocks (1) being greater than 2 mm and less than 7 mm.

2. Pneumatic vehicle tyre according to Claim 1, characterized in that the distance between two sipes (3) in shoulder-side blocks (6) and / or in central blocks (1) is less than 7 mm.

3. Pneumatic vehicle tyre according to Claim 1 or 2, characterized in that the distance between two transverse micro grooves (5) in shoulder-side blocks (6) and / or in central blocks (1) is less than twice, preferably one and a half times and more preferably once, the distance between two sipes (3).

4. Pneumatic vehicle tyre according to one of the preceding claims, characterized in that the sipes (3) and the micro grooves (4) extend on the circumferential surface of the vehicle tyre with a deviation of at most 30°, preferably at most 25°, particularly preferably at most 20° and more preferably at most by 5°, in relation to the axial direction of the pneumatic vehicle tyre.

5. Pneumatic vehicle tyre according to one of the preceding claims, characterized in that an angle a of between 50° and 130°, preferably between 65° and 115° and particularly preferably between 80° and 100°, is formed between the sipes (3) and the transverse micro grooves (5).

6. Pneumatic vehicle tyre according to one of the preceding claims, characterized in that the sipes (3) have a width of 0.5 mm to 0.6 mm and / or a depth at their deepest point of at least 70%.

7. Pneumatic vehicle tyre according to one of the preceding claims, characterized in that the shoulder-side blocks (6) and the central blocks (1) are divided in each case into subareas by the transverse micro grooves (5) crossing the sipes (3) and crossing the micro grooves (4), the subareas being attached to the central blocks (1) and shoulder-side blocks (6) flexibly in relation to adjacent subareas, the subareas of the shoulder-side blocks (6) having a size of less than 100 mm2, preferably less than 80 mm2 and more preferably less than 60 mm2, and the subareas of the central blocks (1) having a size of less than 60 mm2, preferably less than 50 mm2 and more preferably less than 40 mm2.

8. Pneumatic vehicle tyre according to one of the preceding claims, characterized in that the sipes (3) run on the circumference of the tread in a sinusoidal and / or zigzag form and preferably have a bulge in the radial direction.