Large-size low-flatness-ratio tire
By setting transverse steel plates on the central rib and optimizing the crown arc structure, the problems of high rolling resistance and poor comfort of large-size, low-profile tires have been solved, achieving the effect of reducing rolling resistance and improving comfort.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-30
- Publication Date
- 2026-04-07
AI Technical Summary
Traditional large-size, low-profile tires have problems such as high rolling resistance, poor comfort, and a concave center in the contact patch.
The design incorporates transverse steel plates on the central ribs, a three-segment tangential crown arc structure, and a multi-segment arc curve structure to optimize the tread profile, ensure uniform and stable ground contact marks, and reduce rolling resistance.
By reducing tread rigidity through transverse steel strips, vibration and noise are reduced, ensuring a uniform ground contact mark, avoiding edge stress concentration, achieving a near-elliptical ground contact mark, reducing rolling resistance, and improving comfort.
Smart Images
Figure CN224089968U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to tire technical field especially relates to a large size low flat ratio tire. BACKGROUND
[0002] With the rapid development of new energy vehicles, the market demand for tire performance has significantly improved, especially the demand for lightweight, low rolling resistance and high durability of tires has become higher. Since large size low flat ratio tires can better match the high torque output and chassis design of new energy vehicles, and reduce rolling resistance to improve the range, the market share of large size low flat ratio tires continues to increase. In addition, large size low flat ratio tires have larger hub diameters and thinner tire walls, and their appearance is more sporty and luxurious, which can enhance the visual impact of vehicles and are favored by consumers. Moreover, green tire technology is more widely used in large size tires, which meets the global carbon emission regulations, and this also makes the rapid development of large size tires an inevitable trend of the industry.
[0003] However, traditional large size low flat ratio tires have the disadvantages of high rolling resistance, poor comfort, and concave middle ground contact marks. Therefore, it is urgent to provide a large size low flat ratio tire that optimizes the ground contact shape, reduces tire rolling resistance, and improves comfort. SUMMARY
[0004] The details of one or more embodiments of the utility model are presented in the following drawings and description to make other features, objects and advantages of the present application more concise and easy to understand.
[0005] The utility model provides a kind of large size low flat ratio tire, solve the technical problems that traditional large size low flat ratio tire exists high rolling resistance, poor comfort, and concave middle ground contact mark, with the characteristics of optimizing ground contact shape, reduce tire rolling resistance and improve comfort.
[0006] The utility model discloses a large size low flat ratio tire, comprising a tread, a plurality of longitudinal grooves extending along the tire circumference are arranged on the tread, and a pattern block extending along the tire circumference is formed between adjacent longitudinal grooves, wherein the pattern block comprises a central rib at the center line of the tread, a transverse steel sheet transversely penetrating both sides of the central rib is arranged on the central rib, and at least one transverse steel sheet is arranged in each pitch along the tire circumference, and the depth of the transverse steel sheet is 2 / 5-2 / 3 of the maximum depth of the adjacent longitudinal grooves.
[0007] In some embodiments, the pitch width m of the central rib satisfies 20mm≤m<30mm, and one transverse steel sheet is arranged in each pitch.
[0008] In some embodiments, the pitch width m of the central rib satisfies m≥30mm, and two transverse steel sheets are arranged in each pitch.
[0009] In some embodiments, the profile of the tread is divided into a first crown arc and a second crown arc in sequence from the center line of the tread to the shoulder, wherein the axial horizontal width T1 of the first crown arc satisfies T1=(0.35-0.45)×1 / 2TDW, wherein TDW is the design value of the running surface of the tire; the axial horizontal width T2 of the second crown arc satisfies T2=(0.35-0.4)×1 / 2TDW.
[0010] In some embodiments, the first crown arc and the second crown arc are tangent at the connecting point.
[0011] In some embodiments, the radius of curvature TR1 of the first crown arc satisfies TR1=OD×(0.85-1.15), wherein OD is the design value of the outer diameter of the tire; the radius of curvature TR2 of the second crown arc satisfies TR2=TR1 / (1.4-1.8).
[0012] In some embodiments, the profile of the tread further comprises a third crown arc connected to the second crown arc at one end, and the third crown arc and the second crown arc are tangent at the connecting point.
[0013] In some embodiments, the radius of curvature TR3 of the third crown arc satisfies TR3=SW×(0.5-0.8), wherein SW is the design value of the cross-sectional width of the tire.
[0014] In some embodiments, the profile of the tread comprises a plurality of arc-shaped curve structures, wherein each arc-shaped curve structure comprises a first positioning point and a second positioning point, which are respectively located at the inner side end points of two adjacent longitudinal grooves close to each other; a third positioning point, which is located at the 0.3-0.6mm offset position of the midpoint of the line connecting the first positioning point and the second positioning point in the radial direction outward of the tire; and a transition curve, which is a smooth curve continuously extending from the first positioning point through the third positioning point to the second positioning point.
[0015] In some embodiments, the transition curve is tangent to a circle with the midpoint of the line connecting the first positioning point and the second positioning point as the center and R1=0.3-0.6mm as the radius at the third positioning point.
[0016] Compared with the prior art, the large-size low-flat-ratio tire has the advantages that: according to the pitch width of the central rib, a corresponding number of transverse steel sheets are arranged on the central rib, so that the rigidity of the tread can be reduced, the vibration and noise of the tire in the driving process can be reduced, and the comfort can be improved; the large-size low-flat-ratio tire can ensure that the tire can form a uniform and stable mark when being in contact with the ground, avoid stress concentration at the edge, make the crown arc smoothly transition, and be beneficial to reducing the rolling resistance; the large-size low-flat-ratio tire has a tread profile including a plurality of arc curve structures, the central rib long axis of the mark can be avoided from being depressed, an elliptical ground contact mark can be realized, and the tire rolling resistance can be reduced. BRIEF DESCRIPTION OF DRAWINGS
[0017] The drawings described herein are used to provide further understanding of the present application, and form a part of the present application. The illustrative embodiments of the present application and their descriptions serve to explain the present application, and do not constitute an improper limitation on the present application. Among them:
[0018] Figure 1 A schematic view of a tread pattern structure of the large-size low-flat-ratio tire provided by the embodiments of the present application;
[0019] Figure 2 A schematic view of a profile structure of one of the embodiments of the large-size low-flat-ratio tire provided by the embodiments of the present application;
[0020] Figure 3 A schematic view of a profile structure of another embodiment of the large-size low-flat-ratio tire provided by the embodiments of the present application;
[0021] Figure 4 A Figure 3 An enlarged schematic view of position A;
[0022] Figure 5 A schematic view of a ground contact mark of the tire of embodiment 1;
[0023] Figure 6 A schematic view of a ground contact mark of the tire of comparative example 1;
[0024] In the drawings: 1, longitudinal groove, 2, central rib, 3, transverse steel sheet;
[0025] m: pitch width of the central rib;
[0026] TDW: design value of the tire running surface;
[0027] SW: design value of the tire cross section width;
[0028] CL: center line of the tread;
[0029] T1: axial horizontal width of the first crown arc;
[0030] T2: axial horizontal width of the second crown arc;
[0031] TR1: radius of curvature of the first crown arc;
[0032] TR2: radius of curvature of the second crown arc;
[0033] TR3: radius of curvature of the third crown arc;
[0034] P1: first positioning point;
[0035] P2: second positioning point;
[0036] P3: third positioning point. DETAILED DESCRIPTION
[0037] In order to make the purpose, technical scheme and advantages of the utility model more clearly, the following will combine the drawings in the embodiment of the utility model, clearly and completely describe the technical scheme in the embodiment. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by the person skilled in the art without creative labor belong to the protection scope of the utility model.
[0038] In the description of the utility model, it is understood that the orientation or position relationship indicated by the terms "center", "transverse", "longitudinal", "upper", "lower", "inner", "outer" and the like is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the utility model. The terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second", "third" can be explicitly or implicitly included one or more features. The term "longitudinal" refers to the direction of tire rolling; the term "transverse" refers to the direction perpendicular to the tire surface.
[0039] The utility model embodiment provides a large size low flat ratio tire, Figure 1 It is a schematic view of the tread pattern structure of the large size low flat ratio tire according to the utility model embodiment. Reference Figure 1As shown, the large-size low-flat-ratio tire of the utility model embodiment comprises a tread, a plurality of longitudinal grooves 1 extending along the tire circumferential direction are arranged on the tread, and a pattern block extending along the tire circumferential direction is formed between adjacent longitudinal grooves 1, wherein the pattern block comprises a central rib 2 located at the tread center line, a transverse cutting steel sheet 3 is arranged on the central rib 2 and penetrates through both sides of the central rib 2, at least one transverse cutting steel sheet 3 is arranged in each pitch along the tire circumferential direction, the depth of the transverse cutting steel sheet 3 is 2 / 5-2 / 3 of the maximum depth of the adjacent longitudinal groove 1, the pitch width m of the central rib 2 satisfies 20mm≤m<30mm, and one transverse cutting steel sheet 3 is arranged in each pitch; or the pitch width m of the central rib 2 satisfies m≥30mm, and two transverse cutting steel sheets 3 are arranged in each pitch. By arranging the transverse cutting steel sheet 3 on the central rib 2, the integrity of the central rib 2 can be broken, the central rib 2 is changed into small and many pattern blocks in the circumferential direction, the small pattern blocks are more likely to contact the ground when the tread contacts the ground due to the existence of the transverse cutting steel sheet 3, the contact area between the central rib 2 and the ground is increased, meanwhile, the transverse cutting steel sheet 3 can also reduce the rigidity of the central rib 2, reduce the rigidity of the tread, reduce the vibration and noise of the tire in the driving process, and be beneficial to improving the comfort.
[0040] Reference is made to the accompanying drawings Figure 2 As shown, the tread profile of the large-size low-flat-ratio tire of the utility model is sequentially divided into a first crown arc and a second crown arc from the tread center line to the shoulder, and the first crown arc and the second crown arc are tangent at the connecting point. Wherein, the axial horizontal width T1 of the first crown arc satisfies T1=(0.35-0.45)×1 / 2TDW, in the formula, TDW is the design value of the tire running surface; the curvature radius TR1 of the first crown arc satisfies TR1=OD×(0.85-1.15), in the formula, OD is the design value of the tire outer diameter; the axial horizontal width T2 of the second crown arc satisfies T2=(0.35-0.4)×1 / 2TDW; and the curvature radius TR2 of the second crown arc satisfies TR2=TR1 / (1.4-1.8).
[0041] In an embodiment, the tread profile further comprises a third crown arc connected with the second crown arc at one end, and the second crown arc and the third crown arc are tangent at the connecting point. Wherein, the curvature radius TR3 of the third crown arc satisfies TR3=SW×(0.5-0.8), in the formula, SW is the design value of the tire section width, and it has been verified that the third crown arc has little relationship with the tire footprint shape, and mainly affects whether the crown arc transition is smooth. Through the structure design of the above three crown arcs, it is ensured that the tire can form a uniform and stable footprint when contacting the ground, the edge stress concentration is avoided, the three crown arcs are smoothly transitioned, and the rolling resistance is reduced.
[0042] Reference is made to the accompanying drawings Figure 3 and the accompanying drawings Figure 4As shown in the embodiment, the profile of the large-size low-flat-ratio tire comprises multi-segment arc curve structures, wherein each segment arc curve structure comprises a first positioning point P1 and a second positioning point P2, which are respectively located at the inner side endpoints of the adjacent two longitudinal grooves and close to each other; a third positioning point P3 is located at the position offset by 0.3-0.6 mm in the radial direction outside the midpoint of the line connecting the first positioning point P1 and the second positioning point P2; and a transition curve is a smooth curve continuously extending from the first positioning point P1 to the second positioning point P2 through the third positioning point P3. The transition curve is tangent to a circle C with the midpoint of the line connecting the first positioning point P1 and the second positioning point P2 as the center and R1=0.3-0.6 mm as the radius at the third positioning point P3. With this structure design, the third positioning point P3 is higher than the first positioning point P1 and the second positioning point P2, so that the middle of each pattern block preferentially contacts the ground compared with the two sides, which can avoid the concave phenomenon of the middle pattern block and achieve an elliptical contact patch, thereby reducing the rolling resistance of the tire.
[0043] In order to more clearly and specifically introduce the large-size low-flat-ratio tire provided by the embodiment of the utility model, the following will be described in combination with specific embodiments.
[0044] Embodiment 1:
[0045] Tire specification: 235 / 40R19 EV95;
[0046] Profile parameter value: OD=665 mm, SW=254 mm, TDW=214 mm;
[0047] The first crown arc curvature radius TR1=760 mm, the second crown arc curvature radius TR2=475 mm, the third crown arc curvature radius TR3=185 mm, the axial horizontal width of the first crown arc T1=38 mm, and the axial horizontal width of the second crown arc T2=38 mm.
[0048] One transverse steel sheet is arranged in each pitch of the tire circumferential direction.
[0049] The contact patch of the tire after testing in this embodiment is as shown in the figure. Figure 5 As can be seen from the figure, the contact patch length of the central rib is obviously longer than that of the pattern blocks of the left and right ribs, and the overall tire contact patch is in an elliptical shape. The test data results are as follows: the contact patch length of the left rib pattern block on the left side of the tire center line is 118 mm, the contact patch length of the central rib is 128 mm, and the contact patch length of the right rib pattern block on the right side of the tire center line is 115 mm.
[0050] Rectangularity=(118+115) / (2*128)=0.91
[0051] Comparative Example 1:
[0052] Tire specification: 235 / 40R19 EV95;
[0053] Contour parameter values: OD = 665 mm, SW = 254 mm, TDW = 214 mm;
[0054] The first crown arc curvature radius TR1 = 930 mm, the second crown arc curvature radius TR2 = 670 mm, the third crown arc curvature radius TR3 = 180 mm, the axial horizontal width of the first crown arc T1 = 36 mm, and the axial horizontal width of the second crown arc T2 = 36 mm.
[0055] The above parameters of the comparative example are determined according to the conventional product design principle, and the tire footprint is shown in FIG. 1 after the tire is tested. Figure 6 As shown in the figure, the length of the central rib footprint is shorter than that of the left and right rib pattern blocks, and the overall tire footprint is concave in the middle. The test data results are as follows: the length of the left rib pattern block footprint on the left side of the center line of the tread is 122 mm, the length of the central rib footprint is 124 mm, and the length of the right rib pattern block footprint on the right side of the center line of the tread is 116 mm.
[0056] Rectangularity = (122 + 116) / (2 * 124) = 0.96.
[0057] Result analysis: The actual shape of the tire footprint can be determined by the test data results and the calculation of the rectangularity of the tire footprint. The greater the rectangularity, the more the footprint tends to be square. According to the calculation result of the rectangularity, the rectangularity of Example 1 is smaller than that of Comparative Example 1, and the tire footprint shape tends to be elliptical. Figure 5 and Figure 6 It can be seen that the tire footprint shape of Example 1 of the utility model is obviously better than that of the conventional tire footprint of Comparative Example 1, and the tire footprint shape of Example 1 tends to be elliptical, without the phenomenon of short central rib, and the shoulder contacts the ground during tire driving, improving comfort.
[0058] The above examples are only used to illustrate the technical solutions of the utility model and not to limit them; although the utility model has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the specific embodiments of the utility model can be modified or some technical features can be replaced by equivalents; without departing from the spirit of the technical solutions of the utility model, they should be covered in the technical solution range of the utility model claimed.
Claims
1. A large-size, low-profile tire, characterized in that: The tire includes a tread with multiple longitudinal grooves extending along the tire circumference. Adjacent longitudinal grooves form tread blocks extending along the tire circumference. Each tread block includes a central rib located at the centerline of the tread. A transverse steel plate is provided on the central rib, extending laterally through both sides. At least one transverse steel plate is provided in each pitch along the tire circumference. The depth of the transverse steel plate is 2 / 5 to 2 / 3 of the maximum depth of the adjacent longitudinal grooves.
2. The large-size, low-profile tire according to claim 1, characterized in that: The pitch width m of the central rib satisfies 20mm≤m<30mm, and one transverse steel plate is set in each pitch.
3. The large-size, low-profile tire according to claim 1, characterized in that: The pitch width m of the central rib satisfies m≥30mm, and two transverse steel plates are set in each pitch.
4. The large-size, low-profile tire according to claim 1, characterized in that: The tread profile is divided into a first crown arc and a second crown arc from the center line of the tread to the shoulder. The axial horizontal width T1 of the first crown arc satisfies T1 = (0.35~0.45)×1 / 2TDW, where TDW is the design value of the tire tread surface. The axial horizontal width T2 of the second crown arc satisfies T2 = (0.35~0.4)×1 / 2TDW.
5. The large-size, low-profile tire according to claim 4, characterized in that: The first and second crown arcs are tangent at the junction.
6. The large-size, low-profile tire according to claim 4, characterized in that: The first tire crown curvature radius TR1 satisfies TR1=OD×(0.85~1.15), where OD is the design value of the tire outer diameter; the second tire crown curvature radius TR2 satisfies TR2=TR1 / (1.4~1.8).
7. The large-size, low-profile tire according to claim 4, characterized in that: The tread profile also includes a third crown arc that is connected at one end to the second crown arc, and the third crown arc and the second crown arc are tangent at the connection point.
8. The large-size, low-profile tire according to claim 7, characterized in that: The third tire crown curvature radius TR3 satisfies TR3=SW×(0.5~0.8), where SW is the design value of the tire section width.
9. The large-size, low-profile tire according to claim 1, characterized in that: The tread profile includes multiple arc-shaped curve structures, each of which includes a first positioning point and a second positioning point, located at the inner endpoints of two adjacent longitudinal grooves that are close to each other; a third positioning point, located at the midpoint of the line connecting the first and second positioning points, offset 0.3 to 0.6 mm along the radial outward direction of the tire; and a transition curve, which is a smooth curve that extends continuously from the first positioning point through the third positioning point to the second positioning point.
10. The large-size, low-profile tire according to claim 9, characterized in that: The transition curve is tangent to the circle with the midpoint of the line connecting the first and second positioning points as the center and R1 = 0.3 to 0.6 mm as the radius at the third positioning point.