Tire with improved tread pattern
By incorporating recesses and sipes between tire block sections, the uneven wear and insufficient grip issues of all-season tires are resolved, resulting in a more uniform wear distribution and improved grip.
Patent Information
- Application Number
- CN202480025118.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-03-31
- Filing Date
- 2024-03-20
- Publication Date
- 2025-12-12
AI Technical Summary
Existing all-season tires have deficiencies in terms of wear and wear uniformity, especially high wear and uneven wear caused by grooves between the shoulder and middle sections, while also lacking grip on wet and snow-covered roads.
Recesses are created between the blocks of the tire to replace traditional grooves. Combined with sipe tread pattern design, this optimizes the block stiffness and snow performance, reduces wear, and improves grip.
It achieves a more uniform wear distribution, improves grip on wet and snow-covered surfaces, while maintaining good performance on dry surfaces.
Smart Images
Figure CN121127374A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a vehicle tire. One possible application of the disclosed tire involves an all-season tire designed for use in passenger vehicles or commercial vans. The invention can also be applied to other tires, such as winter tires, summer tires, or tires for off-road applications. Background Technology
[0002] All-season tires—used here as a typical example for readability—are known to provide good grip on snow-covered road surfaces while also offering good performance on both dry and wet road surfaces. These tires are designed for year-round use, eliminating the need to switch between summer and winter tires.
[0003] For example, known all-season tires include grooves extending from the center of the tire tread (i.e., from the tire's equatorial plane) toward the tire's shoulder (sometimes also called the "shoulder portion" or "side portion"). These grooves, typically extending in a generally axial direction, are configured to transport water outward from the tire's contact patch with the road to provide contact between the tire block and the road surface. This contact between the block and the road is necessary to provide friction, which provides lateral road holding and further allows the driver to control the vehicle's movement through acceleration, braking, and / or steering.
[0004] Some known tires are provided with grooves that extend in the block in the generally circumferential direction between two consecutive grooves extending generally in the axial direction. These grooves are located between the shoulder portion of the block and the more inner portion (sometimes referred to as the middle and central portions). The shoulder portion of the block is primarily designed to provide acceleration and braking performance because it is typically arranged perpendicular to the rolling direction, such as in V-shaped or S-shaped treads, making it designed to provide frictional forces parallel to the direction of travel, such as braking or acceleration forces. Therefore, braking and acceleration cause deformation of the block, especially in the shoulder portion. To still ensure steering performance and prevent loss of contact between the rubber and the ground, grooves are provided between the shoulder portion and the more axially inward portion (sometimes referred to as the middle portion).
[0005] Therefore, to further improve flexural capacity, it is conceivable to provide additional grooves, for example, between the middle and central sections. However, such grooves suffer from the disadvantage of locally increasing the tire's wear energy due to the added edges. This results in higher total wear and uneven wear on the tread profile, as wear primarily occurs around these grooves.
[0006] Therefore, the object of the present invention is to mitigate these disadvantages and provide a tire with comparable performance, but with lower total wear and more uniform wear distribution across the total width of the tread. Summary of the Invention
[0007] This objective is achieved by providing an improved vehicle tire according to the independent claim. Further embodiments are described in the dependent claims.
[0008] According to an aspect of the invention, a tire for a vehicle is provided, the tire including a tread. The tread includes a set of continuous blocks arranged along the circumference of the tire, wherein each block includes a leading edge and a trailing edge; and a plurality of first grooves arranged on the circumference of the tire, wherein each of the plurality of first grooves is disposed between two blocks in the set of continuous blocks. Each block in the set of continuous blocks includes a first portion and a second portion, the first portion being disposed at a central portion of the tire, the second portion being disposed axially toward a shoulder of the tire relative to the first portion; wherein the first portion and the second portion are formed continuously; wherein a first recess is formed between the first portion and the second portion, and wherein the first recess is disposed in at least one of the leading edge and the trailing edge of the block.
[0009] The continuous formation of the first and second sections, combined with the arrangement of recesses between these sections, allows for high tread flexural capacity, as the recesses function similarly to hinges for the tread. Simultaneously, the benefits of connecting the first and second sections are preserved, particularly the benefits of reduced wear energy and higher longitudinal stiffness. Furthermore, the recesses (or multiple recesses, if present) also contribute to snow trapping, thus increasing the grip of snow tires. Attached Figure Description
[0010] Figure 1 A sketch of a vehicle tire according to this disclosure is shown.
[0011] Figure 2 The half-tread profile of a tire according to this disclosure is shown.
[0012] Figure 3 A close-up view of the block portion containing the recess is shown.
[0013] Figures 4A to 4E Various embodiments of a block having two recesses between a first part and a second part, arranged in different ways, are shown.
[0014] Figure 5 An exemplary embodiment of a V-shaped directional tread pattern according to the present disclosure is shown.
[0015] Figure 6 An exemplary embodiment of an S-shaped tread pattern according to the present disclosure is shown. Detailed Implementation
[0016] To overcome the drawbacks of the prior art as described above, it is desirable to provide a first recess in the leading or trailing edge of the block to locally reduce the stiffness of the block at the location of the recess. This allows the tread to bend around the recess when the tire is under stress and / or strain, as the recessed portion with reduced stiffness can act as a hinge. Thus, a tire that is typically convex can adapt to a generally flat surface. Therefore, the improved bending capability of the recess (or multiple recesses, if present) can increase the tire's contact patch, which allows for improved tire traction on wet, dry, and snow-covered surfaces.
[0017] In addition, the recesses provide an additional edge within the tire, which can further improve tire performance on snow-covered surfaces. Furthermore, the recesses can trap snow within them, further improving traction on snow-covered roads.
[0018] Providing one or more recesses between the first (e.g., central) portion and the second (e.g., intermediate) portion of the tread allows for the omission of grooves between the two portions. Therefore, as described above, the disadvantage associated with additional grooves between the central and intermediate portions—namely, the localized increase in tread wear energy—can be avoided. Furthermore, due to the proposed solution, wear energy can be distributed more evenly across the width of the tread, thus avoiding localized wear peaks.
[0019] Furthermore, grooves arranged approximately perpendicular to the first groove can often cause turbulence in water that is being directed outward through the first groove. By providing recesses instead of grooves, the risk of generating this turbulence can be reduced, thereby improving the tread's drainage capacity and increasing tire traction on wet surfaces.
[0020] Therefore, the recess provides bending and decoupling between adjacent tread sections, while mitigating the negative effects of the groove, such as excessive wear energy and water turbulence.
[0021] In the preferred embodiment described in more detail below, further improvements in traction on snow-covered surfaces are achieved by additionally providing sipes, which are small cuts in the block that typically, but not necessarily, extend in a generally axial direction. Such sipes are configured to trap snow within them and provide additional edges to improve performance on snow-covered surfaces. Providing multiple sipes (which would further improve snow performance) reduces block stiffness and thus compromises wet and dry performance; therefore, it is preferable to provide only a few sipes per block for the tire, and most preferably only one sipe per block, to achieve an acceptable trade-off between snow and wet / dry performance.
[0022] A "groove" refers to a cut in the tread pattern. The width of a groove can vary; for example, a first groove can have a wider width than a second groove, or it can have the same or even smaller width. For example, the width of a groove can be at least 2 mm. The width of a single groove does not necessarily have to be constant: for example, a groove can have a wider opening toward the tread pattern and a smaller width in the radially inward direction. Furthermore, the depth of the groove can vary, and sometimes a groove can extend across the full tread depth (where the full tread depth is the maximum distance between the outermost radial portion of the tire and the bottom of the deepest groove, measured in the radial direction), but this is not always the case. For example, a depth of at least 1 mm, preferably at least 3 mm, is considered.
[0023] "Sipes" also refers to cuts in the tread pattern. As used herein, "sipes" refers to cuts within the tread blocks, not "grooves" that separate the blocks. For example, the width of a sipe can be less than the width of a groove, and for example, less than 2 mm. As with grooves, the width of a sipe does not necessarily have to be constant, and means that allow for a wider opening toward the tread pattern and a smaller width in the radially inward direction can be applied. Furthermore, the depth of the sipe can vary, and sometimes the sipe can extend to the full depth of the tread block, but this is not always the case. For example, a depth of at least 1 mm is considered, preferably at least 20% of the depth of the first groove.
[0024] Figure 1 A sketch of a vehicle tire according to this disclosure is shown.
[0025] according to Figure 1 The tire 100 includes a tread 110. The tread includes a set of continuous blocks 10 and a plurality of grooves 18, each groove 18 being disposed between two blocks 10 in the set of continuous blocks. In addition, sipes 30 may be disposed within each block in the set of continuous blocks 10.
[0026] The blocks can be arranged continuously along the circumferential direction of the tire at 120°.
[0027] In the context of this disclosure, "circumferential direction" 120 refers to a direction perpendicular to the axial direction 130, which is parallel to the direction in which the tire normally rolls, i.e., parallel to the tangential direction relative to the circumference of the tire. Regarding Figure 1 The circumferential direction 120 is therefore a direction in a plane parallel to the yz plane.
[0028] In the context of this disclosure, "axial direction" 130 refers to a direction parallel to the axis of the vehicle on which the tires are normally mounted. Therefore, according to Figure 1 The axial direction 130 is parallel to the x-axis and therefore perpendicular to the yz plane.
[0029] In the context of this disclosure, "radial direction" 140 refers to a direction perpendicular to the axial direction. The radial direction is parallel to the connection between the tire center 150 and the tread surface. Therefore, the radial direction lies in a plane parallel to the yz plane and substantially perpendicular to the axial direction 130 and the circumferential direction 120.
[0030] In the context of this disclosure, "equatorial plane" refers to a plane perpendicular to the axial direction 130° that cuts the cross-sectional width of the tire into two equal halves. Therefore, the equatorial plane is parallel to the yz plane and corresponds to the centerline of the tread's width direction.
[0031] Furthermore, any numerical angles given in this paper should be considered absolute values, i.e., not limited to the orientation of the corresponding angle.
[0032] Figure 2 The half-tread profile of a tire according to this disclosure is shown.
[0033] according to Figure 2 The tire tread comprises a set of continuous blocks 10 arranged along the circumference of the tire. In the context of this disclosure, "continuous blocks" means that the tread comprises a plurality of blocks that follow each other continuously on the circumference of the tire. While it is preferred that all blocks for a tire be provided according to the invention of this disclosure, some blocks arranged between the individual blocks 10 of the set of continuous blocks may not include any recesses between a first (e.g., central) portion and an intermediate (e.g., second) portion of the block.
[0034] according to Figure 2 Each block in block 10 includes a first portion 12 disposed at the central portion of the tire. The central portion of the tire is the portion closest to or adjacent to the equatorial plane 16 of the tire. Furthermore, according to... Figure 2 Each block 10 in the block includes a second portion 14, which is arranged axially toward the shoulder of the tire relative to the first portion 12 and adjacent to the central portion. The second portion 14 can be referred to as the "middle portion". The first portion 12 can be referred to as the "central portion". Figure 2 The first part 12 and the second part 14 are formed continuously, which means that there is no complete interruption between the two parts 12 and 14. Instead, they form a continuous arrangement.
[0035] Therefore, during normal rolling, the first portion 12 and the second portion 14 should be in contact—at least partially—within the tire's track. Thus, for two consecutively formed portions, small cuts separating the two portions are also possible, as long as portions 12 and 14 are at least partially in contact with each other within the tire's track. Similarly, one or more sipes within the block (as previously explained) do not impede the continuous arrangement of the first portion 12 and the second portion 14.
[0036] like Figure 2 As further shown, a first recess 22 is formed between the first portion 12 and the second portion 14. In the example shown, the first recess 22 is arranged in the leading edge of the block 10. However, it can also be alternatively provided at the trailing edge, or recesses can be provided on both edges between the first and second portions (see also below).
[0037] In the context of this disclosure, "leading edge" (sometimes also referred to as "traction edge") refers to the edge of the block that primarily responds to longitudinal traction when it is applied to the tire. Typically, the "leading edge" is the edge of the block whose length is greater than the lateral edge of the block, and the leading edge first contacts the ground when the block of the tire, rolling in the preferred rolling direction, enters the tire-ground contact imprint.
[0038] The "tailing edge," sometimes referred to as the "braking edge," is the edge of the block that primarily responds to longitudinal braking force when it is applied to the tire. Typically, the "tailing edge" is the edge of the block whose length is greater than the lateral edge of the block, and it is the last edge that loses contact with the ground when the block of the tire, rolling in the preferred rolling direction, leaves the tire-ground contact imprint.
[0039] The first recess 22 can be arranged such that the stiffness of block 10 is reduced in the region surrounding the first recess 22 compared to the stiffness in the first portion 12 and the second portion 14. Thus, each block in the set of consecutive blocks 10 is configured to bend around the first recess 22 when the tire is rolling.
[0040] Therefore, the first recess provides a hinge-like function and allows for improved bending capability of the block: by providing the recess to locally reduce the stiffness of the block, the block portion around the recess can be configured to behave as a hinge, thereby allowing the tire to bend between the first portion 12 and the second portion 14, enabling the tire, which is normally shaped in a convex manner, to adapt to a generally flat surface. Thus, the improved bending capability of the first recess 22 can increase the tire's contact patch, which allows for improved tire traction on wet, dry, and snow-covered surfaces.
[0041] Furthermore, the first recess 22 allows for reduced mechanical coupling between the first portion 12 and the second portion 14. Thus, the first portion 12 and the second portion 14 can respond respectively to stresses and strains applied to the block during the normal rolling state of the tire. Such strains and stresses are applied to the tire, for example, during braking, acceleration, or steering, and throughout the rolling process.
[0042] Tires known from the prior art achieve decoupling of the first portion 12 and the second portion 14 by providing additional grooves arranged in a generally circumferential direction. However, the circumferential grooves provide additional edges that locally increase the wear energy of the tread. This results in increased wear and uneven distribution of wear energy, causing the wear to be unevenly distributed across the width of the tread, i.e., the block portion near the circumferential grooves experiences more wear than other parts of the block.
[0043] By providing a recess 22 between the first portion 12 and the second portion 14, additional grooves can be omitted, allowing for improved bending and decoupling of the block portion through the recess 22, while omitting increased and unevenly distributed wear energy.
[0044] In some embodiments, the first recess 22 may be disposed at the leading edge of the block 10, and the block may further include a second recess 24 disposed at the trailing edge of the block 10. Providing the second recess further improves the block's separation / bending capability. In particular, since the first recess 22 and the second recess 24 are disposed at opposite edges of the block, the direction of bending of the block can be controlled more precisely.
[0045] In some embodiments, the connecting line 26 between the geometric center 222 of the first recess 22 and the geometric center 242 of the second recess 24 may have an inclination angle of at least 0° and at most 80° relative to the circumferential direction. Preferably, the inclination angle of the connecting line 26 may be at least 0° and at most 60°. The geometric center may also be referred to as the "centroid" and corresponds to the arithmetic mean position of all points on the surface of the respective recess. The connecting line 26 may also correspond to the dividing line between the first portion 12 and the second portion 14.
[0046] The connecting line 26 between the geometric centers of the recesses 22 and 24, which have tilt angles within a specified range, provides optimized block bending capability while maintaining the block's circumferential stiffness.
[0047] In some embodiments, the first recess 22 may have a vertical extension that is perpendicular to the outer surface of the block and is in contact with the ground when the tire is in normal condition, the vertical extension being at least 20% of the depth of the first groove 18.
[0048] according to Figure 2The tread may also include a plurality of sipes 30. In the illustrated tread pattern, each of the plurality of sipes 30 may preferably extend generally along the shape of at least one of the first portion 12 and the second portion 14 of each of the group of consecutive blocks 10. However, other arrangements and shapes of the sipes on the outer tread surface are also possible, such as wavy shapes, serrated shapes, etc. The sipes do not necessarily have to follow the shape of the blocks. For example, sipes may be included only along a portion of the shape of a block, or these sipes may have a different angle of inclination relative to the circumferential direction than the block or a portion of the block below. Furthermore, while some sipes may have walls extending radially toward the center of the tire, some sipes may also have wavy shapes, serrated shapes, etc., in the radial direction. In addition, such sipes may also be inclined relative to the radial direction. Some sipes may include protrusions near the bottom of the sipe. The sipes 30 are able to trap snow therein and provide additional edges to the tread. This improves traction on snow-covered surfaces.
[0049] In some embodiments, the plurality of sipes 30 may define an edge component (EI) corresponding to the ratio between the projected lengths (SAP) of the plurality of sipes in the axial direction and the circumference (C) of the tread, such that...
[0050]
[0051] Wherein EI is at least 2 and at most 20. Preferably, EI can be at least 2 and at most 16, more preferably at least 2 and at most 15.
[0052] The tire circumference C is measured at the outermost radial circumference of the tire when inflated. The same specifications as those described below for tire track measurement apply to inflation pressure and ambient temperature.
[0053] A high edge composition provides better snow-trapping capability, which improves tire traction on snow-covered surfaces. However, a high edge composition also results in lower block stiffness, which generally degrades braking / acceleration performance on dry surfaces. Edge compositions within one of the aforementioned ranges offer a particularly good trade-off between traction on snow-covered surfaces and braking / acceleration performance on dry surfaces.
[0054] Preferably, the edge component is balanced with the arrangement of the recesses and any second grooves: for example, since the recesses locally reduce stiffness, the edge component should be kept within the indicated range to ensure sufficient stiffness. Furthermore, since the recesses aid in snow trapping, fewer grooving patterns or shorter grooving lengths may be required. If each block has more than one recess, and / or if one or more recesses have a large surface area, it may be advantageous to provide an edge component (e.g., at least 2 and at most 10) within the lower portion of the range.
[0055] according to Figure 2 Tires can also have a void volume, which is the volume of all the grooves, sipes, and recesses in the tread, as well as the volume of the rubber contained in the tread, together constituting the total volume of the tread. That is, if the total volume of the tire is V... T The void volume is V V The volume of the rubber is V R Then the total volume V T Will be V T =V V +V R In a preferred embodiment, the void volume V V With rubber volume V R The ratio between V V / V R It can be at least 0.20 and at most 0.40. Preferably, the ratio V V / V R The ratio V can be at least 0.24 and at most 0.37, more preferably at least 0.28 and at most 0.35. V / VR It is directly related to the stiffness of the tread profile. Therefore, a higher ratio V V / V R This indicates a higher amount of voids in the tread, which results in lower tread stiffness and is therefore beneficial for snow performance. A lower ratio V V / V R This indicates a higher rubber content in the tread, which results in higher stiffness and thus improved braking performance. A specific range of void-to-rubber ratios offers the optimal trade-off between snow and dry performance, providing tires that exhibit good braking performance on dry surfaces and good traction on snow-covered surfaces.
[0056] In some embodiments described in more detail elsewhere in this document, the tread includes additional blocks on the opposite side of the tire's equatorial plane 16. In some embodiments described elsewhere in this document, these additional blocks may have relative to... Figure 2The axially symmetric arrangement of block 10 shown results in a V-shaped pattern. In other embodiments described elsewhere herein, additional blocks may be point-symmetric, resulting in an S-shaped pattern. In any case, this disclosure does not relate to a specific orientation of the blocks, but can be applied to blocks of various shapes and orientations.
[0057] Furthermore, although this disclosure describes generally symmetrical tread patterns, i.e., having the same or similar tread construction on both sides of the equatorial plane, it should be understood that the concepts described herein can also be applied to asymmetrical tread patterns, i.e., patterns having generally different tread constructions on both sides of the equatorial plane of the tire.
[0058] Typically, block 10 serves to provide contact with the ground when the tire is rolling. The edges and surfaces of the block are configured to provide friction between the tire and the ground for grip, thereby allowing general road holding and vehicle motion control by the driver through acceleration, braking, or steering.
[0059] according to Figure 2 The tread also includes a plurality of first grooves 18 arranged on the circumference of the tire, wherein each of the plurality of first grooves 18 is arranged between two blocks 10 in the set of consecutive blocks. Preferably, the grooves 18 begin near the equatorial plane 16 of the tire and extend toward the shoulder end of the tread to open at the outer edge of the tire. The grooves 18 are generally defined by adjacent blocks 10.
[0060] The primary purpose of groove 18 is to guide water along the groove towards the shoulder of the tire as it rolls on the ground, and to spray the water out from there, thus expelling water from the contact patch. Therefore, groove 18 provides improved tire performance, especially under wet and slippery road conditions. Furthermore, since the groove defines continuous blocks, it also provides edges to the blocks to improve snow performance. Additionally, the groove allows for improved wear performance because it allows for greater flexibility of the tread elements, reducing block slippage on the ground and consequently reducing the wear effects that cause wear.
[0061] according to Figure 2 The tread also includes a plurality of second grooves 20, wherein each of the second grooves 20 is arranged between a shoulder portion and a middle portion of each of the blocks 10. In some embodiments, each second groove 20 is arranged in a generally circumferential direction. In some embodiments, each second groove 20 may be arranged in a generally straight line, for example, with a small inclination relative to the circumferential direction; in other embodiments, such as Figure 2As shown, each second groove 20 can be arranged in a serrated pattern, for example, including three different inclined portions. The serrated pattern of the second groove 20 allows for partial interruption of the tire's strain and slip behavior, thereby improving the distribution of wear energy along the axial extension of the block 10.
[0062] Therefore, in a preferred embodiment, the second groove typically serves to decouple the shoulder portion of block 10 from the middle portion of block 10. For example, during acceleration or braking, the shoulder portion of block 10 may become particularly tense because it is arranged generally perpendicular to the circumferential direction of the tire. This can cause deformation of block 10 within the shoulder portion. Therefore, in order to ensure good steering performance and lateral road grip as well as braking and acceleration, it is desirable to mechanically decouple the shoulder portion of block 10 from the middle portion. This decoupling is preferably achieved by providing a second groove 20 therebetween.
[0063] Therefore, in a preferred embodiment, the invention does not necessarily include any grooves arranged in the fundamental circumferential direction (however, this is also possible). Instead, in a preferred embodiment, the fundamental circumferential grooves arranged between two or more inner portions of the block (e.g., the middle portion and the central portion) can be omitted and replaced by one or more recesses as described herein.
[0064] Figure 3 A close-up view of the block portion containing the recess is shown.
[0065] Figure 3 Block 10 shown corresponds to Figure 2 One of the blocks in block 10. Therefore, Figure 3 Block 10 also includes a first portion 12 and a second portion 14, and a first recess 22 disposed between the first portion 12 and the second portion 14. For example... Figure 3 As shown, block 10 may further include a second recess 24 disposed between the first portion 12 and the second portion 14. Figure 3 Each of the recesses 22 and 24 includes a surface area of 25. Figure 3 In this diagram, for clarity, the surface area 25 is shown only for the second recess 24; however, it should be understood that, unless otherwise stated, all the characteristics described for one recess may also be applied to the other recess.
[0066] In some embodiments, the first recess 22 and / or the second recess 24 may have a diameter of at least 4 mm. 2 And at most 60mm 2 The surface area is 25. Preferably, the first recess 22 and / or the second recess 24 can have a surface area of at least 6 mm. 2 And at most 50mm 2 The surface area is 25.
[0067] This range offers a good trade-off between wear and performance. A higher surface area results in improved performance because bending capacity increases with larger recesses. However, larger recesses also increase localized wear. Therefore, it is possible to arrange recesses with at least 4mm... 2 The surface area of the recess 22 is increased to achieve greater bending capacity, but the surface area of the recess 22 can preferably be at most 60 mm. 2 To avoid increased wear and tear.
[0068] In some embodiments, the first recess 22 and / or the second recess 24 may have an extension measured perpendicular to the tangent of the block, the extension being at least 1.5 mm and at most 45% of the width of the block as measured at the axial outer end of the recess. Preferably, the first recess 22 and / or the second recess 24 may have an extension 225 measured perpendicular to the tangent of the block, the extension being at least 1.5 mm and at most 35% of the width of the block as measured at the axial outer end of the recess.
[0069] Similar to the above, this provides a good trade-off between wear and performance. The higher extension of the recess, measured perpendicular to the block, results in improved breakaway / bending performance, but also increases localized tread wear. Therefore, preferably, an extension of at least 1.5 mm, measured perpendicular to the tangent of the block, can be selected to increase the block's breakaway / bending characteristics. Furthermore, an extension of up to 45% of the width of block 10 can be selected. In this context, the width of the block can be perpendicular to the block tangent and measured at a location adjacent to the first recess 22. By selecting a width of up to 45% of the block width, the increase in wear can be limited to achieve the desired trade-off between wear and breakaway / bending performance.
[0070] In some embodiments, the first recess 22 and / or the second recess 24 may have at least one edge that is inclined relative to the axial direction of the tire (e.g., Figure 3 As shown, the tilt angle 227) is at least 0° and at most 30°. Preferably, the first recess 22 and / or the second recess 24 may have at least one edge that is tilted at least 5° and at most 20° relative to the axial direction of the tire.
[0071] Within this slope range, the edge can contribute to grip on snow-covered ground. Therefore, by providing a recess with at least one edge within a specific range, the snow performance of the tire can be improved.
[0072] In some embodiments, the first recess 22 and / or the second recess 24 may have outer edges 226, 246 and inner edges 228, 248, the outer edges being the edges of the recesses 22, 24 closest to the shoulder of the tire, the inner edges being opposite to the outer edges, and wherein for the first recess 22, the outer edge 226 is inclined between 0° and 30° relative to the axial direction of the tire, and wherein for the second recess 24, the inner edge 248 is inclined between 0° and 30° relative to the axial direction of the tire.
[0073] While the above embodiments relate to blocks with three parts, blocks with more parts (e.g., four or more parts) are also possible. This can be achieved, for example, by subdivision, i.e., dividing a part into one or more consecutively formed sub-parts. In such embodiments, recesses can be arranged between any two consecutively formed parts, such as between the first and second parts, between the second and third parts, between the third and fourth parts, etc.
[0074] Furthermore, while the above embodiments include a recess at each block edge, alternative embodiments may exist in which two or more smaller recesses are arranged close to each other on one edge in order to behave similarly to a single recess described in the above embodiments.
[0075] Figures 4A to 4E Various embodiments of a block having two recesses between a first part and a second part, arranged in different ways, are shown.
[0076] Figure 4A and Figure 4B An embodiment of the present disclosure is shown in which the first recess 22 and the second recess 24 are not circumferentially aligned. This means that there is no plane parallel to the equatorial plane 16 of the tire that cuts through both the first recess 22 and the second recess 24.
[0077] exist Figure 4A In one embodiment, the first recess 22 is arranged more inwardly in the axial direction than the second recess 24. Figure 4B In one embodiment, the first recess 22 is arranged further inward in the axial direction than the second recess 24. Figure 4A and Figure 4B The embodiment shown provides a more uniform distribution of block stiffness along the axial extension of the block.
[0078] Alternatively, Figure 4C and Figure 4DAn embodiment of the present disclosure is shown, wherein the first recess 22 and the second recess 24 are partially circumferentially aligned. This means that a plane parallel to the equatorial plane 16 can be constructed that cuts both the first recess 22 and the second recess 24, but at the same time, a plane parallel to the equatorial plane can be constructed that cuts only one of the first recess 22 or the second recess 24.
[0079] exist Figure 4C In one embodiment, the first recess 22 is arranged more inwardly in the axial direction than the second recess 24. Figure 4D In one embodiment, the first recess 22 is arranged further inward in the axial direction than the second recess 24. Figure 4C and Figure 4D The embodiment shown similarly provides a more uniform distribution of block stiffness along the axial extension of the block.
[0080] Alternatively, Figure 4E An embodiment of this disclosure is shown, wherein the first recess 22 and the second recess 24 are completely circumferentially aligned. This means that a first plane parallel to the equatorial plane 16 of the tire intersects the two outer edges of the first recess 22 and the second recess 24, and a second plane parallel to the equatorial plane 16 of the tire intersects the two inner edges of the first recess 22 and the second recess 24. This embodiment provides particularly improved bending capability of the block in the desired portion because the block is further narrowed by means of the completely circumferentially aligned recesses.
[0081] Figure 5 An exemplary embodiment of a V-shaped directional tread pattern according to the present disclosure is shown.
[0082] according to Figure 5 Some embodiments of the tread may include a second set of continuous blocks 50, which typically corresponds to a first set of continuous blocks 10, arranged on opposite sides of the tire's equatorial plane 16. In some embodiments, such as Figure 5 As shown, the second set of continuous blocks 50 can be arranged symmetrically with respect to the first set of blocks 10, thereby creating a V-shaped tread pattern with a preferred rolling direction. The V-shape offers the advantage of improved drainage performance because when the tire rolls in the preferred rolling direction, water can be expelled from the contact patch by means of two opposing first grooves in opposite axial directions of the tread. Therefore, traction on wet roads can be improved. While a directional tread pattern with a preferred rolling direction is advantageous for wet surfaces, other embodiments are also possible.
[0083] For example, Figure 6 Exemplary embodiments of an S-shaped tread pattern according to this disclosure are shown. For some embodiments, according to Figure 6In addition to the first set of continuous blocks 10, the tread may also include a second set of continuous blocks 50. The second set of continuous blocks 50 may be arranged on opposite sides of the equatorial plane 16 of the tire. Compared with the above embodiment including a V-shaped tread pattern, the second set of continuous blocks 50 may be arranged to be symmetrical with respect to the first set of blocks 10, thereby producing an S-shaped tread pattern that does not have a preferred rolling direction.
[0084] Tire track measurement
[0085] In the context of this disclosure, "tire track" refers to all the portions of a tire that are in contact with the ground when the tire is inflated and under load. Tire tracks provide information about the behavior of the tread profile under normal conditions; that is, the tire tracks indicate which portions of the block are in contact with the ground under static load conditions.
[0086] When analyzing tire tracks, the corresponding tire is typically inflated, with the pressure depending on the tire type. For standard radial passenger tires with a nominal section width of 195 mm or less, a tire pressure of 1.9 bar is used. For standard radial passenger tires with a nominal section width of 205 mm or more, a tire pressure of 2.0 bar is used. For reinforced radial passenger tires of all sizes, a pressure of 2.3 bar is used. For tires for commercial vans, trucks, etc., standardized inflation pressures according to the European Tire and Rim Technology Organization (ETRTO) are used. All measurements are performed at room temperature.
[0087] The tires were then loaded under the following conditions: for radial passenger tires, a load corresponding to 88% of the tire load index according to ETRTO specifications was applied. For tires used in commercial vans, trucks, etc., a load corresponding to the ETRTO single load rating was applied. For measurement, ink was applied to the tire tread profile, and the tire was then pushed against a card according to the aforementioned specifications, leaving an ink imprint, which could then be analyzed. The imprint was evaluated on three tire sections at 120° intervals around the tire circumference. The measurements analyzed in the imprint were then averaged across the three measurement sections.
[0088] Tire void volume and rubber volume measurement
[0089] In the context of this application, tire void volume is also measured under tread conditions. That is, the tire is inflated in the same manner as described above regarding tire tread measurement. The void volume is measured by a laser measurement system capable of detecting the relative depth of each pixel relative to the tread surface. Thus, by integrating all measured pixels, the total void volume in the contact tread can be calculated. The total tread volume can be calculated as the product of the tire's tread width (FW) and circumference (C) multiplied by the weighted average depth of the first groove. The total rubber volume is the difference between the total tread volume and the total void volume.
[0090] The measurements given in this disclosure are taken under tread conditions and on new tires that have not been exposed to wear prior to the measurements.
[0091] List of icon numbers
[0092] 10, 50 yuan
[0093] 12 Part 1
[0094] 14 Part Two
[0095] 16 Equatorial Plane
[0096] 18 First trench
[0097] 20 Second trench
[0098] 22, 24 concave parts
[0099] 25 surface area
[0100] 26 connecting cable
[0101] 30-groove pattern
[0102] 100 tires
[0103] 110 tread
[0104] 120 circumferential direction
[0105] 130 axial direction
[0106] 140 radial direction
[0107] 150 Center
[0108] Geometric centers 222 and 242
[0109] 225 extension
[0110] 226, 246 outer edges
[0111] 227 tilt angle
[0112] 228, 248 inner edges
Claims
1. A tire for a vehicle, the tire comprising a tread, the tread comprising: A set of continuous blocks arranged along the circumference of the tire, wherein each block includes a leading edge and a trailing edge; and A plurality of first grooves are arranged on the circumference of the tire, wherein each of the plurality of first grooves is arranged between two blocks in a set of consecutive blocks; Each block in the set of consecutive blocks includes: The first part, the first part being disposed at the central portion of the tire, and The second part is arranged axially toward the shoulder of the tire relative to the first part; The first part and the second part are formed continuously; A first recess is formed between the first portion and the second portion, and the first recess is disposed in at least one of the leading edge and the trailing edge of the block.
2. The tire according to claim 1, wherein the first recess has a diameter of at least 4 mm. 2 And at most 60mm 2 Surface area.
3. The tire according to any one of the preceding claims, wherein the first recess has an extension measured perpendicular to the tangent of the block, the extension being at least 1.5 mm and at most 45% of the width of the block measured at the axial outer end of the recess.
4. The tire according to any one of the preceding claims, wherein the first recess has at least one edge, the at least one edge being inclined at least 0° and at most 30° relative to the axial direction of the tire.
5. The tire according to any one of the preceding claims, wherein the first recess is disposed at the leading edge of the block, and the block further comprises a second recess disposed at the trailing edge of the block.
6. The tire of claim 5, wherein the connecting line between the geometric center of the first recess and the geometric center of the second recess has an inclination angle of at least 0° and at most 80° with respect to the circumferential direction.
7. The tire of claim 5, wherein the first recess and the second recess are arranged such that a plane parallel to the equatorial plane of the tire intersects both the first recess and the second recess.
8. The tire of claim 5, wherein both the first recess and the second recess have an outer edge and an inner edge, the outer edge being the edge of the recess closest to the shoulder of the tire, the inner edge being opposite to the outer edge, and wherein a first plane parallel to the equatorial plane of the tire intersects both outer edges of the first recess and the second recess, and a second plane parallel to the equatorial plane of the tire intersects both inner edges of the first recess and the second recess.
9. The tire according to any one of claims 5 to 8, wherein the second recess has at least one of the following: (a) at least 4mm 2 And at most 60mm 2 Surface area; (b) An extension measured perpendicular to the tangent of the block, the extension being at least 1.5 mm and at most 45% of the width of the block as measured at the axial outer end of the recess; and (c) At least one edge, said at least one edge being inclined at least 0° and at most 30° relative to the axial direction of the tire.
10. The tire according to any one of claims 5 to 9, wherein both the first recess and the second recess have an outer edge and an inner edge, the outer edge being the edge of the recess closest to the shoulder of the tire, the inner edge being opposite to the outer edge, and wherein for the first recess, the outer edge is inclined at at least 0° and at most 30° relative to the axial direction of the tire, and wherein for the second recess, the inner edge is inclined at at least 0° and at most 30° relative to the axial direction of the tire.
11. The tire according to any one of the preceding claims, wherein the first recess has a vertical extension measured perpendicular to the outer surface of the block, wherein when the tire is in a rolling state, the outer surface of the block is in contact with the ground, and the vertical extension is at least 20% of the depth of the first groove.
12. The tire according to any one of the preceding claims, wherein the tread further comprises: Multiple sipes define an edge component EI, where EI corresponds to the ratio between the sum of the projected lengths of the multiple sipes in the axial direction (SAP) and the circumference (C) of the tread. ， The EI is at least 2 and at most 20.
13. The tire according to any one of the preceding claims, wherein the ratio between the void volume and the rubber volume is at least 0.20 and at most 0.40, and preferably at least 0.28 and at most 0.35.