Tire comprising composite grooves

Abstract

The invention relates to the field of tread design of tires, and discloses a tire containing composite grooves, a plurality of transverse composite grooves are distributed in a tread shoulder of the tire in the circumferential direction, each composite groove transversely and alternately comprises a first unit and a second unit, the first unit is provided with an external cavity, the external cavity is communicated with the outer side of the surface of the tread shoulder, and the second unit is communicated with the external cavity. The second unit is provided with an internal cavity and a transverse cutter groove communicated with the internal cavity, the internal cavity is hidden in the surface of the tread shoulder, and the adjacent cavities are communicated with each other. The tread design of the tire is suitable for heavy or light load-carrying vehicles, the rolling resistance coefficient of the tire can be effectively reduced, and the road holding force of the tire is improved, so that the service life of the tire is prolonged, the fuel economy of the vehicle is improved, and the vehicle has higher driving stability and controllability.

Description

Technical Field

[0001] The present invention relates to the field of tire tread design, in particular to a tire comprising composite grooves. Background Art

[0002] The ground contact characteristics of tires are one of the important properties that reflect the dynamics and economy of tires. Unbalanced distribution of tire ground contact pressure will affect the traction, braking and handling performance of tires, and will also affect the vehicle handling and driving safety. The pattern structure is an important factor affecting the ground contact performance of tires. Tread patterns with different structures will lead to large differences in pressure distribution. Therefore, in the design and production process of tires, it is necessary to consider the effects of factors such as tire model parameters and pattern structure on the balance of tire ground contact pressure distribution in order to improve the dynamics, economy and safety performance of tires.

[0003] Balanced shoulder contact pressure means that the tire contact surface pressure is evenly distributed in the shoulder area without obvious bias, which has an important impact on the performance and life of the tire. If the tire shoulder contact pressure is unevenly distributed, it may cause lateral deviation of the tire, uneven torque output, uneven shoulder wear and other problems, affecting the service life of the tire. Balanced shoulder contact pressure can improve the handling stability and driving comfort of the tire, extend the service life of the tire, and reduce maintenance costs. Therefore, manufacturers need to pay attention to the balance of tire shoulder contact pressure distribution when designing tires.

[0004] Uneven wear means that during the use of the tire, instead of being worn evenly across the entire tread surface, some areas wear more than other areas. This uneven wear can cause the tire to be removed from the vehicle prematurely to be replaced with a new tire, thereby increasing the driving cost per unit distance traveled.

[0005] Grooves are defined by longitudinal or transverse grooves in the material. These areas are more easily deformed than sipes. When the tire encounters an obstacle during driving, the grooves can deform accordingly, thus having a certain impact on the driving stability and smoothness of the vehicle. However, this deformation also reduces the compression and shear stiffness of the tire, causing the tire to deform more easily and twist under load.

[0006] In contrast, the width of the sipe is smaller, and the walls on both sides abut against each other when entering the contact patch, so the sipe can provide stronger support and rigidity, making it easier for the tire to maintain its shape during driving. In addition, the sipe can also improve the tire's grip and handling performance, especially in slippery road conditions.

[0007] When an object moves on a supporting surface, if there is no relative sliding between the edge of the object and the supporting surface at the moment of contact, the object is said to be in non-slip rolling, also known as pure rolling. In the state of pure rolling, the contact point between the tire and the road surface always remains stationary, and no relative sliding occurs, thereby reducing the loss of friction. However, in actual applications, due to the deformation cycle of the tire material, the tire cannot completely maintain a pure rolling state during driving, but there is a certain degree of sliding and deformation. This deformation causes energy loss, which increases rolling resistance. In short, as the hysteresis loss increases, the rolling resistance of the tire will also increase accordingly.

[0008] Tires in the prior art have a certain total void volume when they are new, and there is also available void volume in the tire's contact patch. For these tires, the European ETRTO standard defines commonly used inflation conditions and load conditions to evaluate the void volume in the tire's contact patch leading to the tread surface. Specifically, the European ETRTO standard measures parameters such as tire pressure, load, speed, and substitutes these parameters into the standard formula to calculate the tire's void volume. This void volume includes the total volume of the tire material plus the total void volume. Among them, the available void volume refers to the void volume existing in the tire's contact patch. If there is water on the road surface, this available void volume may be partially or completely filled.

[0009] For these tires, multiple factors need to be balanced during tire design and manufacturing to achieve optimal performance. For example, when considering the void volume of a tire, it is necessary to consider multiple factors such as tire grip, handling performance, and durability, and make comprehensive considerations and optimize the design based on the actual use environment and needs. Summary of the invention

[0010] In view of the deficiencies of the prior art, the present invention provides a tire comprising composite grooves, which is suitable for heavy or light load vehicles, has a longer service life, can improve the fuel economy of the vehicle, and enables the vehicle to have higher driving stability and controllability.

[0011] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions: A tire including composite grooves, wherein the tread of the tire includes at least three longitudinally oriented grooves, a plurality of transverse composite grooves are distributed circumferentially on the tread shoulder of the tire, the circumferential spacing of the composite grooves is D, and the circumferential width is d, the composite grooves transversely alternately include a first unit and a second unit, the first unit is provided with an external cavity, the external cavity is connected to the outer surface of the tread shoulder, the second unit is provided with an internal cavity and a transverse sipe connected to the internal cavity, the internal cavity is hidden in the surface of the tread shoulder, adjacent cavities are connected to each other, the circumferential width of the external cavity is d, the transverse width is Lm, and the transverse width of the internal cavity is Ln.

[0012] When the tire is worn, the total volume of the tire tread is increased to make the tire more wear-resistant and durable, thereby extending the service life of the tire. The design of the composite groove can precisely limit the reduction of the total volume of the tire tread.

[0013] Preferably, in order to optimize the stiffness of the shoulder with respect to wear and rolling resistance, the number of transversely oriented composite grooves needs to be limited, and the circumferential spacing of the composite grooves can be set to vary with the circumferential position, that is, the circumferential spacing of the composite grooves is a variable value.

[0014] Preferably, 15mm≤D, 1.8mm≤d≤5mm.

[0015] Preferably, 0.5*Lm≤Ln≤2*Lm.

[0016] Preferably, the angle between the composite groove and the horizontal direction is α, 5°≤α≤15°.

[0017] Preferably, the depth of the groove is H, the depth of the external cavity is u, the depth of the transverse sipe is v, and the depth of the internal cavity is w, then 2mm≤v, v+w≤0.9H, 1.3*v≤u≤v+0.8*w.

[0018] Preferably, adjacent composite grooves are relatively offset and staggered in the lateral direction, and the staggered value is T. This design can disperse the acoustic power over time and make the ground pressure distribution better, thereby reducing noise.

[0019] Preferably, 0.3*Lm ≤T≤Lm+0.7Ln.

[0020] Preferably, the total volume void ratio of the tread is ≤15%.

[0021] Preferably, the total volume void ratio of the tread is ≤10%.

[0022] The tread design of the tire of the present invention is suitable for heavy or light load vehicles, and can effectively reduce the tire rolling resistance coefficient and improve the tire grip, thereby extending the life of the tire, improving the fuel economy of the vehicle, and making the vehicle have higher driving stability and controllability. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the right half of the tire tread of the present invention.

[0024] Figure 2 for Figure 1 Schematic diagram of the AA section.

[0025] Figure 3 for Figure 1 Schematic diagram of the BB section.

[0026] Figure 4 for Figure 1 Schematic diagram of the CC section.

[0027] Figure 5 It is a schematic diagram of the structure of the right half of the tread of the comparative tire.

[0028] Figure 6 for Figure 5 Schematic diagram of the EE section. DETAILED DESCRIPTION

[0029] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0031] Tire tread surface: corresponds to the entire basic surface of the tire in contact with the road surface. When this type of tire is running, the tread surface is in close contact with the road surface, playing the role of bearing the vehicle's load, transmitting power and braking.

[0032] Radial: refers to the direction perpendicular to the tire's axis of rotation, that is, the thickness direction of the tread. This direction is usually used to describe the structure and design of the tire.

[0033] Transverse direction or axial direction: refers to the direction parallel to the axis of rotation of the wheel, that is, the width of the tire.

[0034] Circumferential direction or longitudinal direction: refers to the direction along the circumference of the tire tread.

[0035] The equatorial midplane, which is the plane perpendicular to the axis of rotation, divides the wheel into two equal halves.

[0036] like Figure 1-Figure 4 As shown, a tire comprising composite grooves, the tread of the tire comprises at least three longitudinally oriented grooves 31 and 32, and ribs 21 and 22 are arranged between the grooves. Figure 1It is a schematic diagram of the right side tread of the tread equatorial midplane XX'. Figure 1 The right half tread in the figure includes half of the longitudinally oriented groove 31, the longitudinally oriented groove 32, the rib 21 between the groove 31 and the groove 32, and the tread shoulder 22 on the right side of the groove 32. The width of the right half tread is 205 mm, the thickness of the worn material is 9.5 mm, and it is equipped with a tire pattern formed by 111 shoulder composite grooves with a maximum depth of 8 mm.

[0037] The tread shoulder 22 has a plurality of transverse composite grooves 220 distributed circumferentially, the circumferential width of the composite groove 220 is d, the circumferential pitch is D, 1.8mm≤d≤5mm, 15mm≤D. Specifically, the circumferential pitch D in this embodiment adopts a three-pitch design of 20.7mm, 23mm, and 25.5mm.

[0038] The composite groove 220 laterally alternately includes a first unit 221 and a second unit 222. The first unit 221 is provided with an external cavity 41, and the external cavity 41 is connected to the outer surface of the tread shoulder 22. The second unit 222 is provided with an internal cavity 43 and a transverse knife groove 42 connected to the internal cavity 43. The internal cavity 43 is hidden in the surface of the tread shoulder 22. Adjacent cavities and knife grooves are connected to each other. The circumferential width of the external cavity 41 is d=3mm and the lateral width is Lm=10mm. The lateral width of the internal cavity 43 is Ln=10mm.

[0039] The angle between the composite groove 220 and the horizontal direction is α=8°.

[0040] The depths of the grooves 31 and 32 are H, the depth of the external cavity 41 is u, the depth of the transverse sipe 42 is v, and the depth of the internal cavity 43 is w, then 2mm≤v, v+w≤0.9H, 1.3*v≤u≤v+0.8*w. Specifically, in this embodiment, H=8mm, u=4mm, v=2mm, and w=4mm.

[0041] Adjacent composite grooves 220 are relatively offset and staggered in the transverse direction, and the staggered value is T. Specifically, T in this embodiment is 10 mm.

[0042] When the tread is new, the total volume void ratio formed in the tread is 13%.

[0043] like Figure 5 As shown in the figure, as a comparative example, the tread shoulder 22 has a plurality of transverse grooves 223 distributed circumferentially, the circumferential width of the transverse groove 223 is d=3 mm, the circumferential pitch D is designed with three pitches of 20.7 mm, 23 mm, and 25.5 mm, the angle between the transverse groove 223 and the horizontal direction is α=8°, and the section depth is shown in FIG. Figure 6 , where u=4mm, H=8mm.

[0044] The test was conducted on a light-duty vehicle tire with a size of 205 / 75R16, using the current EU standard. Compared with the control example, the tire rolling resistance coefficient of the embodiment of the present invention was improved by 1 N / kN; under the same road conditions, the vehicle's grip was improved by 20%.

[0045] The above is a description of the embodiments of the present invention. Through the above description of the disclosed embodiments, professionals and technicians in the field can implement or use the present invention. Various modifications to these embodiments will be apparent to professionals and technicians in the field. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown in this article, but will conform to the widest range consistent with the principles and novelties disclosed herein.

Claims

1. A tire comprising a composite groove, characterized in that: The tread of the tire comprises at least three longitudinally oriented grooves (31, 32), and the tread shoulder (22) of the tire has a plurality of transverse composite grooves (220) distributed circumferentially, the circumferential spacing of the composite grooves (220) being D and the circumferential width being d, and the composite grooves (220) transversely alternately comprising first units (221) and second units (222), the first unit (221) being provided with an external cavity (41), the external cavity (41) being connected to the outer surface of the tread shoulder (22), the second unit (222) being provided with an internal cavity (43) and a transverse sipe (42) connected to the internal cavity (43), the internal cavity (43) being hidden in the surface of the tread shoulder (22), and adjacent cavities being connected to each other, the external cavity (41) having a circumferential width of d and a transverse width of Lm, and the internal cavity (43) having a transverse width of Ln.

2. A tire comprising a composite groove according to claim 1, characterized in that: The circumferential spacing of the composite grooves (220) is a variable value.

3. A tire comprising a composite groove according to claim 1, characterized in that: 15mm≤D, 1.8mm≤d≤5mm.

4. A tire comprising a composite groove according to claim 1, characterized in that: 0.5*Lm≤Ln≤2*Lm.

5. A tire comprising a composite groove according to claim 1, characterized in that: The angle between the composite groove (220) and the horizontal direction is α, 5°≤α≤15°.

6. A tire comprising a composite groove according to claim 1, characterized in that: The depth of the grooves (31, 32) is H, the depth of the external cavity (41) is u, the depth of the transverse sipe (42) is v, and the depth of the internal cavity (43) is w, then 2mm≤v, v+w≤0.9H, 1.3*v≤u≤v+0.8*w.

7. A tire comprising a composite groove according to claim 1, characterized in that: Adjacent composite grooves (220) are relatively offset and staggered in the transverse direction, and the staggered value is T.

8. A tire comprising composite grooves according to claim 7, characterized in that: 0.3*Lm ≤T≤Lm+0.7Ln.

9. A tire comprising a composite groove according to claim 1, characterized in that: The total volume void ratio of the tread is ≤15%.

10. A tire comprising a composite groove according to claim 9, characterized in that: The total volume void ratio of the tread is ≤10%.

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