A high wear low rolling resistance radial tire

Abstract

The application relates to the technical field of load radial tires, and discloses a high-abrasion low-rolling-resistance load radial tire, the tread of the tire body is composed of two arc tangent sections, namely a first arc section and a second arc section, the second arc section is located in the middle of the tread, the first arc section is located on both sides of the tread, the arc radii of the first arc section and the second arc section satisfy 0.3 <= TR1:TR2 <= 0.6, the radial height difference between the outer contour center endpoint of the tread and the shoulder endpoint is H, wherein 5.5 <= H <= 7.5; the ratio of the tire running surface width XSW and the tire section width DMW satisfies 0.77 <= XSW / DMW <= 0.9; the ratio of the minimum distance JD from the outer contour shoulder endpoint of the tire to the inner contour line of the tire and the center thickness MT of the tread satisfies 1.34 <= JD / MT <= 1.55; the tread of the tire is divided into five pattern blocks by four pattern grooves; the groove widths of the four pattern grooves from one side of the tire to the other side are GW1, GW2, GW3 and GW4 respectively, wherein GW1=GW4>GW3=GW2, and the groove depth relationship of the four pattern grooves is GD1=GD4>GD3=GD2.

Description

Technical Field

[0001] This invention relates to the field of heavy-duty radial tire technology, and in particular to a high-wear, low-rolling-resistance heavy-duty radial tire. Background Technology

[0002] In the automotive industry, major OEMs inevitably impose performance requirements on tires—a key component—when implementing vehicle lightweighting and fuel economy improvements. As the core component in contact with the ground, tires' wear resistance and rolling resistance directly impact vehicle operating costs, safety, and energy economy, representing two crucial indicators of overall tire performance. However, current technologies often present irreconcilable technical contradictions between these two performance aspects, becoming a core bottleneck restricting tire performance upgrades.

[0003] On the one hand, due to the intense friction under heavy loads, the industry's conventional approach to improve tire wear performance is to increase the amount of reinforcing agents such as carbon black in the tread compound formulation, or to select rubber polymers with high cross-linking density. This enhances the bonding strength between rubber molecules, reducing particle shedding and tread wear during ground friction. However, such designs significantly increase the rigidity of the rubber material and decrease the flexibility of the molecular chains. This increases the deformation resistance generated when the tire contacts the ground, leading to a higher rolling resistance coefficient. This is especially true in new energy vehicles, directly resulting in a shorter driving range, while in gasoline vehicles, it manifests as increased fuel consumption.

[0004] To reduce rolling resistance, current technologies often employ narrow treads and low aspect ratios in the tire carcass structure, or simplify the tread pattern (such as reducing the number of tread grooves and increasing the area of ​​the tread blocks) to reduce tread creep deformation and air resistance during tire operation. However, simplified tread designs reduce the grip stability of the tread blocks, and to ensure basic wear resistance, the rigidity of the tread blocks needs to be further increased, leading to accelerated localized tread wear. At the same time, the narrow tread design concentrates the contact pressure, and without the use of special wear-resistant materials, rapid wear can easily occur in the center of the tread, ultimately shortening the tire's lifespan.

[0005] Furthermore, the diversification of vehicle driving scenarios further amplifies this contradiction. For example, low rolling resistance tires designed for urban commuting scenarios show significant wear resistance issues when driving on frequent starts and stops or rough roads; while high wear resistance tires designed for heavy loads or complex road conditions cannot meet the current automotive industry's requirements for energy conservation and emission reduction due to their higher rolling resistance.

[0006] Therefore, how to break through the technical dilemma that "improving wear resistance will inevitably lead to increased rolling resistance, or reducing rolling resistance will inevitably sacrifice wear resistance" and develop tires that balance high wear resistance and low rolling resistance has become a technical problem that the industry urgently needs to solve. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this invention is to provide a high-wear, low-rolling-resistance heavy-duty radial tire that simultaneously achieves high wear and low rolling resistance performance.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0009] A high-wear, low-rolling-resistance heavy-duty radial tire includes a base rubber on the tread, a base rubber under the tread, a belt layer, a carcass, a sidewall, a bead wrap, a nylon reinforcement layer, a soft triangular rubber, a hard triangular rubber, and a steel wire ring. The outer contour of the tire crown is formed by two tangent arcs, namely the first arc TR1 and the second arc TR2. The second arc is located in the middle of the crown, and the first arc is located on both sides of the crown. The radii of the first and second arcs satisfy 0.3≤TR1:TR2≤0.6. The radial height difference from the center endpoint of the outer contour of the crown to the shoulder endpoint is H, where 5.5≤H≤ 7.5; The ratio of tire tread width XSW to tire section width DMW satisfies 0.77≤XSW / DMW≤0.9; The ratio of the minimum distance JD from the end point of the tire outer contour shoulder to the tire inner contour line to the tread thickness MT satisfies 1.34≤JD / MT≤1.55; Four tread grooves divide the tread into five tread blocks; The groove widths of the four tread grooves are GW1, GW2, GW3 and GW4, where GW1=GW4>GW3=GW2, and the groove depths of the four tread grooves are GD1=GD4>GD3=GD2.

[0010] As a further implementation, the ratio of the upper side height H1 to the lower side height H2 of the tire horizontal axle should satisfy 1.02≤H1 / H2≤1.12.

[0011] As a further implementation, from one side of the tire to the other, the tread blocks are A, B, C, D, and E, and the width ratio of the five tread blocks A, B, C, D, and E is 1.36±3%: 1±3%: 1.08±3%: 1±3%: 1.36±3%.

[0012] As a further implementation, from one side of the tire to the other, the width ratio of the four tread grooves is 4.3±1.5%:1±1.5%:1±1.5%:4.3±1.5%.

[0013] As a further implementation, the depth ratio of the four patterned grooves is 1.03:1:1:1.03.

[0014] As a further implementation, the groove walls of the patterned grooves GD1 and GD4 make an angle α with the vertical direction, and the angle satisfies the following range: 10°≤α≤13°;

[0015] As a further implementation, the relationship between the height RSH of the upper end of the soft triangular adhesive and the height YSH of the upper end of the hard triangular adhesive is 2.33≤YSH / RSH≤2.77.

[0016] As a further implementation, the radial distance ZKH from the toe opening to the heel point is higher than the height TTH of the inverted end of the tire body, and 0.7≤ZKH / TTH≤1.1.

[0017] As a further implementation, the rubber compound used in the tread has a hysteresis loss tangent of 0.011≤tanδ≤0.14 at 60℃, and the rubber compound used in the base rubber has a hysteresis loss tangent of 0.050≤tanδ≤0.075 at 60℃, in order to ensure rolling resistance performance.

[0018] As a further implementation, the ratio of the elongation at break of the tread compound and the base compound at room temperature is 1.19≤AT / AB≤1.35, and the ratio of the tensile strength of the tread compound and the base compound at room temperature is 0.98≤CT / CB≤1.09.

[0019] The beneficial effects of the present invention are as follows:

[0020] This invention effectively controls the tire's contact patch by adjusting parameters such as the tire profile design, the radius ratio of the crown arc, the radial height difference H between the center endpoint of the tire crown and the shoulder endpoint, the position of the tire's horizontal axis, and the thickness of the shoulder. It balances the radius difference between the tire shoulder and the center of the crown from the rim center point under load, preventing abnormal tire wear and effectively improving tire wear performance. By reducing the width of the longitudinal grooves and increasing the tread pattern saturation, wear performance is improved. Simultaneously, using narrower GW2 and GW3 groove widths effectively reduces the stress and strain of tread blocks B, C, and D, thus reducing the hysteresis loss of tread components under alternating stress and further improving rolling resistance. Optimizing the compound formulations of the tread and base rubber ensures the wear resistance of tread components while reducing the hysteresis loss tangent (tanδ), thereby reducing tread energy loss and effectively improving rolling resistance. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0022] Figure 1 This is a schematic diagram of the structure of a heavy-duty radial tire in an embodiment of the present invention;

[0023] Figure 2 This is a parameter distribution diagram of a heavy-duty radial tire in an embodiment of the present invention;

[0024] Figure 3 This is a parameter distribution diagram of a heavy-duty radial tire in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the groove wall angle of a heavy-duty radial tire in an embodiment of the present invention;

[0026] Figure 5 This is a distribution diagram of tread parameters for a heavy-duty radial tire in an embodiment of the present invention.

[0027] The diagram exaggerates the spacing or dimensions between parts to show their positions; the diagram is for illustrative purposes only.

[0028] The components are: 1. Tread base rubber, 2. Tread under base rubber, 3. Belt layer, 4. Carcass, 5. Sidewall, 6. Bead wrap, 7. Nylon reinforcement layer, 8. Soft triangle rubber, 9. Hard triangle rubber, 10. Steel wire bead. Detailed Implementation

[0029] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0030] Example 1

[0031] In a typical embodiment of the present invention, reference is made to Figure 1 As shown, a high-wear, low-rolling-resistance heavy-duty radial tire has the following structure: 1 base rubber on the tread, 2 base rubber on the undertread, 3 belt layer, 4 tire body, 5 sidewall, 6 bead wrapping, 7 nylon reinforcement layer, 8 soft triangle rubber, 9 hard triangle rubber, and 10 steel wire ring.

[0032] The tire body is the tire carcass 4, whose outer surface is the tread. The outer side of the tire carcass 4 is the sidewall 5, and the inner side is the bead. A steel wire ring 10 is located at the bottom of the tire carcass. The bead is filled with triangular rubber, which includes soft triangular rubber 8 and hard triangular rubber 9. The tread includes a base rubber 1 on the upper tread and a base rubber 2 on the lower tread, from the outside to the inside. It is understood that the structure of a heavy-duty radial tire is existing technology and will not be described in detail here.

[0033] like Figure 1 As shown, the outer contour of the tread has an arc-shaped structure on the tire interface, and the outer contour of the tire crown is composed of two tangent arc segments, namely the first arc segment and the second arc segment. The second arc segment is located in the middle of the crown, and the first arc segment is located on both sides of the crown. The arc radii of the first arc segment and the second arc segment satisfy 0.3≤TR1:TR2≤0.6.

[0034] The radial height difference between the center endpoint of the outer contour of the tread and the end endpoint of the shoulder, i.e., the crown height, is H, and its height satisfies the following range: 5.5≤H≤7.5.

[0035] It is understandable that an excessive crown arc height (H) may lead to excessively high ground pressure at the center of the tread, resulting in increased wear of the tread blocks and reduced service life. At the same time, a smaller crown arc height (H) increases the pressure on the tire shoulder area, which may lead to increased wear at the tire shoulder and uneven wear.

[0036] The minimum distance from the end point of the tire's outer contour shoulder to the tire's inner contour line, i.e., the tire shoulder thickness JD, is given by the ratio of the tire's tread center thickness MT, which satisfies the condition 1.34≤JD / MT≤1.55.

[0037] It is understandable that increased shoulder thickness can lead to excessive shoulder pressure and friction, resulting in uneven wear; conversely, insufficient shoulder thickness and rigidity can exacerbate shoulder deformation and cause abnormal wear.

[0038] The ratio of tire tread width XSW to tire section width DMW satisfies: 0.77 ≤ XSW / DMW ≤ 0.9. It is understood that increasing the ratio of tire tread width XSW to tire section width DMW can improve wear performance, but it will reduce tire durability. In this embodiment, the ratio is 0.77 ≤ XSW / DMW ≤ 0.9, and 1.34 ≤ JD / MT ≤ 1.55, which balances tire durability and high wear resistance.

[0039] In tire design, the tread is composed of two tangent arcs, and the radius ratio is controlled to be 0.3≤TR1:TR2≤0.6. The curvature transition between the center of the crown (the second arc) and the shoulder (the first arc) is smooth. When rolling, the radial deformation difference between different areas of the tread is small, which can keep the crown flat enough to obtain a large contact area. The rectangularity of the contact imprint is improved, and the contact pressure distribution is more uniform. This can avoid the occurrence of uneven wear during driving, making the tread wear uniform and taking into account the requirements of high wear, low heat generation and long life.

[0040] In addition, designing the tread into two tangent arcs allows the wear rate of the shoulder and the central tread block to be more consistent, avoiding the common uneven wear phenomenon of "shoulder wear" or "middle wear". At the same time, the stress concentration in the shoulder is reduced, reducing the risk of wear such as chipping and breakage, and allowing the tire to maintain stable wear performance under high mileage and high load conditions.

[0041] like Figure 3 As shown, the tire tread is divided into five tread blocks by four tread grooves. From one side of the tire to the other, the widths of the four tread grooves are GW1, GW2, GW3, and GW4, where GW1=GW4>GW3=GW2. Specifically, from one side of the tire to the other, the width ratio of the four tread grooves GW1:GW2:GW3:GW4 is 4.3±1.5%:1±1.5%:1±1.5%:4.3±1.5%.

[0042] From one side of the tire to the other, the tread blocks are A, B, C, D, and E. Among them, the three groups of tread blocks B, C, and D correspond to the position of the second arc, and the two groups of tread blocks A and E correspond to the position of the first arc.

[0043] The width ratios of the five patterned blocks A, B, C, D, and E are: 1.36±3%: 1±3%: 1.08±3%: 1±3%: 1.36±3%.

[0044] By controlling the width of the tread grooves to increase the saturation of the tread pattern, the rolling resistance of the tire can be reduced. The widths of the two middle tread grooves, W2 and GW3, and the widths of the tread grooves on both sides, GW1 and GW4, are also controlled.

[0045] From one side of the tire to the other, the depths of the four tread grooves are GD1, GD2, GD3, and GD4, respectively, with the relationship GD1=GD4>GD3=GD2. The ratio of the depths of the four tread grooves, GD1:GD2:GD3:GD4, is 1.03:1:1:1.03. By controlling the depth of the tread grooves, the tire's low rolling resistance and high wear resistance are coordinated.

[0046] Furthermore, the ratio of the upper height H1 to the lower height H2 of the tire's horizontal axle should satisfy 1.02 ≤ H1 / H2 ≤ 1.12. Different ratios will lead to different stress and strain distributions in the tire. When the H1 / H2 ratio is too large, the stress and strain will be concentrated in the tire shoulder area, which may cause damage to the tire shoulder area. When the ratio is too small, it may cause excessive stress in the tire bead area, resulting in bead damage.

[0047] The rubber compound used in the tread has a hysteresis loss tangent of 0.011≤tanδ≤0.14 at 60℃, and the rubber compound used in the base rubber has a hysteresis loss tangent of 0.050≤tanδ≤0.075 at 60℃, in order to ensure rolling resistance performance.

[0048] The ratio of the elongation at break of the tread compound to the base compound at room temperature is 1.19≤AT / AB≤1.35, and the ratio of the tensile strength of the tread compound to the base compound at room temperature is 0.98≤CT / CB≤1.09.

[0049] If the elongation at break is too high, the rigidity of the rubber compound will decrease, and the tread blocks will be prone to excessive deformation under heavy loads; if the elongation at break is too low, the rubber compound will be prone to excessive rigidity and insufficient deformation, leading to an increase in the local wear rate.

[0050] By optimizing the compound formulations of the tread and base rubber, the wear resistance of the tread area is ensured while reducing energy loss in the crown area.

[0051] By adjusting parameters such as the tire profile design, the radius ratio of the tread arc, the radial height difference H between the center endpoint of the tire tread outer profile and the shoulder endpoint, the position of the tire horizontal axis, and the thickness of the shoulder, the tire's wear performance can be effectively improved.

[0052] Furthermore, the relationship between the height of the upper end point RSH of the soft triangular rubber and the height of the upper end point YSH of the hard triangular rubber is 2.33≤YSH / RSH≤2.77. The radial distance ZKH from the toe bead wrap to the tire heel point is higher than the height TTH of the tire carcass reverse wrap end point, 0.7≤ZKH / TTH≤1.1. This ensures a reasonable layout of the toe bead wrap, optimizes the structural design, and avoids stress concentration in the tire carcass reverse wrap end area during tire rolling.

[0053] The outer contour of the tire crown is composed of two tangent arc segments, namely the first arc segment and the second arc segment, and the radius TR1 of the first arc segment and the radius TR2 of the second arc segment satisfy the following relationship: 0.3≤TR1:TR2≤0.6; at the same time, the radial height difference H from the center endpoint of the outer contour of the tire tread to the end endpoint of the tire shoulder is preferably 6.3mm; the tire crown contour trend is optimized, the shape of the contact patch is adjusted, the tire shoulder contact patch length is reduced, the rectangularity of the contact patch under standard air pressure and load is improved, the tread pressure is evenly distributed, and the tire wear performance is improved.

[0054] The four tread grooves have widths of GW1, GW2, GW3, and GW4, with a width ratio of 4.3:1:1:4.3. The four tread grooves have depths of GD1, GD2, GD3, and GD4, with a depth ratio of 1.03:1:1:1.03. This design ensures tread stiffness and low rolling resistance, while also facilitating even pressure distribution on the shoulder and preventing abnormal tire wear.

[0055] Table 1

[0056]

[0057] Table 1 shows the shoulder pressure balance parameters for different tire shoulder thicknesses and crown arc heights. The pressure balance parameters are between 95% and 100%, indicating that the shoulder pressure distribution is more uniform. It can be seen that as the ratio of tire shoulder thickness to tread center thickness decreases and the crown arc height increases, the rectangularity increases, the shoulder pressure decreases, and the pressure balance parameters are within the optimal range, which improves tire wear resistance and increases service life.

[0058] Table 2

[0059]

[0060] Table 2 shows the simulated rolling resistance values ​​under different tread pattern saturation and groove width conditions. Comparative analysis of the results in the table shows that increasing the tread pattern saturation and reducing the groove width can effectively reduce the rolling resistance coefficient of the tire.

[0061] Table 3

[0062]

[0063] Table 3 shows the shear strain amplitude at the endpoints of the durability simulation under different schemes. Observing the data in the table, it can be seen that among the three schemes, the shear strain amplitude at the endpoints of the belt layers in Examples 2# and 3# is slightly smaller than that in Comparative Examples 1 and 2, indicating that the durability of the belt layers 2# and 3# is better. At the same time, the shear strain amplitude at the endpoints of the tire carcass in Examples 2# is better than that in the other two schemes, indicating that the durability of the bead area is better.

[0064] Table 4

[0065]

[0066] Table 4 shows the FEA simulation values. Due to the difference in radius between the coronary center and the shoulder, relative slippage exists between the coronary center and the shoulder throughout their entire lifespan. Reducing the inflation arc height h can reduce the relative slippage between the shoulder and the coronary center, thereby improving the uniformity of wear. The slippage in the coronary center is greater than that in the shoulder, and the ground pressure in the coronary center is also greater. Therefore, reducing the grounding length in the coronary center and increasing the grounding length in the shoulder, thereby reducing the grounding pressure in the coronary center, can improve wear performance.

[0067] Table 5

[0068]

[0069] Table 5 shows the measured values ​​of wear resistance for different products. The comparison data shows that, after contour and pattern design, the road test wear mileage and wear resistance are improved compared to competing product 1 and competing product 2, and the wear performance is improved.

[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-wear, low-rolling-resistance heavy-duty radial tire, comprising a base rubber on the tread, a sub-base rubber on the tread, a belt layer, a carcass, a sidewall, a bead wrap, a nylon reinforcing layer, a soft triangular rubber, a hard triangular rubber, and a steel wire ring, characterized in that, The outer contour of the tire crown is composed of two tangent arcs, namely the first arc and the second arc. The second arc is located in the middle of the crown, and the first arc is located on both sides of the crown. The arc radius TR1 of the first arc and the arc radius TR2 of the second arc satisfy 0.3≤TR1:TR2≤0.

6. The radial height difference from the center endpoint of the outer contour of the crown to the shoulder endpoint is H, where 5.5mm≤H≤7.5mm. The ratio of the tire tread width XSW to the tire section width DMW satisfies 0.77≤XSW / DMW≤0.9; The ratio of the minimum distance JD from the end point of the tire's outer contour shoulder to the tire's inner contour line to the tread center thickness MT is 1.34≤JD / MT≤1.55; The tire tread is divided into five tread blocks by four tread grooves; From one side of the tire to the other, the groove widths of the four tread grooves are GW1, GW2, GW3 and GW4, where GW1=GW4>GW3=GW2, and the groove depths of the four tread grooves are GD1=GD4>GD3=GD2; From one side of the tire to the other, the width ratio of the four tread grooves is 4.3±1.5%:1±1.5%:1±1.5%:4.3±1.5%; the depth ratio of the four tread grooves is 1.03:1:1:1.

03.

2. The high-wear, low-rolling-resistance heavy-duty radial tire according to claim 1, characterized in that, The ratio of the upper height H1 to the lower height H2 of the tire horizontal axle should satisfy 1.02≤H1 / H2≤1.

12.

3. A high-wear, low-rolling-resistance heavy-duty radial tire according to claim 1, characterized in that, From one side of the tire to the other, the tread blocks are A, B, C, D, and E. The width ratio of the five tread blocks A, B, C, D, and E is 1.36±3%: 1±3%: 1.08±3%: 1±3%: 1.36±3%.

4. A high-wear, low-rolling-resistance heavy-duty radial tire according to claim 1, characterized in that, The relationship between the height of the upper end point RSH of the soft triangular adhesive and the height of the upper end point YSH of the hard triangular adhesive is 2.33≤YSH / RSH≤2.

77.

5. A high-wear, low-rolling-resistance heavy-duty radial tire according to claim 4, characterized in that, The radial distance ZKH from the toe opening to the heel point is higher than the height TTH of the inverted end of the fetal body, and 0.7≤ZKH / TTH≤1.

1.

6. A high-wear, low-rolling-resistance heavy-duty radial tire according to claim 1, characterized in that, The rubber compound used in the tread has a hysteresis loss tangent of 0.011≤tanδ≤0.14 at 60℃, and the rubber compound used in the base rubber has a hysteresis loss tangent of 0.050≤tanδ≤0.075 at 60℃, in order to ensure rolling resistance performance.

7. A high-wear, low-rolling-resistance heavy-duty radial tire according to claim 6, characterized in that, The ratio of the elongation at break of the tread compound to the base compound at room temperature is 1.19≤AT / AB≤1.35, and the ratio of the tensile strength of the tread compound to the base compound at room temperature is 0.98≤CT / CB≤1.09.

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