High-rigidity, puncture-resistant, and anti-cracking agricultural tire
By adopting a composite structure of 3 layers of reverse-wrapped carcass cord and 4 layers of narrow buffer cord in agricultural tires, optimizing cord angle and elongation, and combining it with vulcanization process for one-piece molding, the problem of tire cracking and puncture in harsh environments is solved, achieving improved high rigidity and puncture resistance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XUZHOU XUGONG TIRES
- Filing Date
- 2025-07-22
- Publication Date
- 2026-07-10
AI Technical Summary
Existing agricultural tires are prone to cracks and punctures in the tread crown under harsh operating conditions, resulting in shortened service life and increased maintenance costs.
It adopts a composite structure of 3 layers of reverse-wrapped body cord and 4 layers of narrow buffer cord. The angle between the cord and the center line of the tire crown is 53°-54°, the cord elongation is 1.036-1.04, the width of the buffer cord decreases radially in a stepped manner, and it is integrally formed by vulcanization process to avoid stress concentration and interlayer separation.
It significantly improves tire rigidity and resistance to deformation, reduces cracks at the tread root, extends service life, reduces the probability of rubber embrittlement and cracking, and improves puncture resistance.
Smart Images
Figure CN224476775U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of agricultural tire technology, specifically a high-rigidity, puncture-resistant, and crack-resistant agricultural tire. Background Technology
[0002] In agricultural production, the dry and cold climate of Northwest and Northeast China makes it easy for sharp and hard objects such as stubble and stones left in the fields to puncture and cut tires during the combined harvesting of crops such as corn, cotton, and soybeans. Meanwhile, the tread area of agricultural tires experiences the most complex stress during inflation and operation: the bottom of the tread grooves must simultaneously withstand radial, sectional, and circumferential tension, and the tread blocks and their roots undergo repeated compression and stretching deformation upon contact with the ground. In low-temperature winter conditions, tire rubber compounds are prone to embrittlement, leading to a significant decrease in elastic recovery and resistance to flexural elongation. Under these conditions, the surface of the tread rubber compound is highly susceptible to cracking under the tensile stress generated by inflation, which then gradually propagates inwards.
[0003] Existing agricultural tires generally suffer from low tread saturation and excessive tread depth, further exacerbating flexural deformation in the tread area. Under the influence of these multiple factors, cracks frequently occur at the root of the tread pattern in traditional tires, not only shortening tire lifespan but also increasing maintenance costs for agricultural machinery, and in severe cases, even affecting agricultural production efficiency. Therefore, developing a highly durable agricultural tire that can adapt to harsh operating environments, reduce tread cracks, and prevent punctures by hard objects has become an urgent technical problem to be solved in this field.
[0004] Chinese Patent CN206812721U discloses an agricultural tire using different polymer fiber materials, including a tread, a ply structure, a sidewall, and a steel wire ring structure. The steel wire ring structure is encapsulated within the inner rubber, the inner rubber within the ply structure, and the ply structure within the tread rubber. The key feature is that the ply layers are arranged as an outer ply layer and an inner ply layer, with the outer ply layer made of nylon and the inner ply layer made of polyester. Compared to traditional designs, this invention avoids the problems of tire delamination and cracking caused by the shrinkage, high elongation, and poor durability and heat resistance of the tire material at high temperatures, thus improving the lifespan and durability of the agricultural tire. However, while the above device optimizes overall strength through the difference in materials between the inner and outer ply layers, the overall puncture resistance remains relatively low. Therefore, those skilled in the art urgently need to solve these technical problems. Utility Model Content
[0005] The present invention aims to solve the above-mentioned prior art and improve the puncture resistance of agricultural tires.
[0006] The technical solutions adopted in this utility model are as follows:
[0007] A high-rigidity, puncture-resistant, and crack-resistant agricultural tire includes a carcass ply and a buffer ply. The carcass ply adopts a 3-layer reverse-wrapped structure, and the buffer ply consists of 4 layers of narrow buffer ply stacked sequentially from the inside to the outside along the radial direction of the tire in the crown area of the carcass ply.
[0008] The width of each of the four narrow buffer fabric layers is smaller than the width of the tire's running surface, and the width of each buffer fabric layer decreases sequentially from the inside to the outside along the radial direction of the tire.
[0009] The angle between the cord of the tire carcass and the center line of the tire crown is 53°-54°, and the elongation of the cord is 1.036-1.04.
[0010] By adopting the above technical solutions and combining precise matching of cord angle and elongation, the overall rigidity of the tire can be significantly improved. The three-layer reverse wrapping structure enhances the tire carcass's resistance to deformation, and the radially decreasing width design of the four-layer narrow buffer cords can gradually disperse the stress in the tread area, avoiding the risk of cracking caused by stress concentration at the edge of the traditional wide buffer layer. At the same time, the optimized combination of cord angle and elongation improves the tread's resistance to flexural deformation and reduces the problem of cracks at the tread root, thereby achieving a synergistic improvement in high rigidity, puncture resistance, and crack prevention.
[0011] Furthermore, the buffer fabric includes a first buffer fabric, a second buffer fabric, a third buffer fabric, and a fourth buffer fabric, which are stacked together. The width of the first buffer fabric is 5mm-15mm smaller than the width of the tire's running surface.
[0012] By adopting the above technical solution, limiting the width of the first layer of buffer fabric to 5mm-15mm smaller than the tire tread width ensures that the buffer structure covers the core stress area of the tire crown while avoiding direct contact between the edge of the buffer layer and the transition area of the tire shoulder. This design reduces stress accumulation in the tire shoulder area caused by an excessively wide buffer layer, lowers the probability of rubber embrittlement and cracking in low-temperature environments, and lays the foundation for the gradient width design of the outer buffer fabric, further optimizing the stress dispersion effect.
[0013] Furthermore, the width of the second layer of buffer fabric is the width of the first layer of buffer fabric minus 20mm-30mm.
[0014] By adopting the above technical solution, the width of the second layer of buffer fabric is reduced by 20mm-30mm compared to the first layer, forming a stepped buffer structure that is wider on the inside and narrower on the outside. This design causes the radial stress of the tire crown to gradually decrease along the thickness of the buffer layer, avoiding stress concentration caused by a single-width buffer layer and enhancing the tire crown's resistance to punctures by sharp objects. At the same time, the narrow outer buffer fabric can reduce the flexural deformation of the tread compound, delaying the initiation and propagation of cracks.
[0015] Furthermore, the width of the third buffer curtain is 70% of the tire travel surface width, and the width of the fourth buffer curtain is 20mm-30mm smaller than the width of the third buffer curtain.
[0016] By adopting the above technical solution, the width of the third layer of buffer fabric is determined to be 70% of the driving surface width, and the fourth layer is reduced by 20mm-30mm compared to the third layer, further refining the gradient distribution of the buffer layers. This design, through precise control of the width ratio of each layer, ensures a linear transition of stress from the center of the tire crown to the tire shoulder, ensuring uniform deformation of the tread blocks upon contact with the ground. At the same time, the narrow design of the outermost buffer fabric avoids the stress concentration area on the tire shoulder, solving the shoulder cracking problem caused by excessively wide buffer layer coverage in traditional tires.
[0017] Furthermore, the buffer curtain uses the same curtain material as the tire body curtain.
[0018] By adopting the above technical solution and using materials of the same specifications as the tire carcass ply to manufacture the cushioning ply, the modulus matching between the tire carcass and the cushioning layer can be ensured, avoiding insufficient interlayer bonding due to differences in material properties. The consistent shrinkage rate of the same material during vulcanization reduces the risk of interlayer delamination, simplifies the production process, reduces material compatibility issues, and improves tire structural stability and durability.
[0019] Furthermore, the tire carcass ply and the buffer ply are integrally formed through a vulcanization process, and the edges of the buffer ply all avoid the stress concentration area on the tire shoulder.
[0020] By adopting the above technical solution, the carcass cord and the cushioning cord are integrally formed through vulcanization, which can strengthen the interlayer interface bonding strength and avoid the defects of bubbles and delamination caused by traditional layer bonding. The design of the cushioning cord edge avoiding the stress concentration area of the tire shoulder directly reduces the fatigue damage of the rubber in the stress superposition area. Especially in low temperature environment, it can effectively inhibit the expansion of cracks from the tire shoulder to the tire crown, and significantly extend the service life of the tire under harsh agricultural conditions.
[0021] This utility model has the following beneficial effects:
[0022] 1. This utility model adopts a composite structure of 3 layers of reverse-wrapped carcass ply and 4 layers of narrow buffer ply, and sets the angle between the cord of the carcass ply and the vertical direction of the center line of the tire crown to 53°-54° and the cord elongation value to 1.036-1.04, which significantly improves the overall rigidity of the tire, enhances the tire's resistance to deformation, and gradually disperses the stress in the crown area, avoiding the risk of cracking caused by stress concentration at the edge of the traditional wide buffer layer. At the same time, it improves the crown's resistance to flexural deformation, reduces the problem of cracks at the tread root, and achieves a synergistic improvement in high rigidity, puncture resistance and crack prevention.
[0023] 2. By limiting the width of the first layer of buffer fabric to be 5mm-15mm smaller than the width of the tire tread, this utility model ensures that the buffer structure covers the core stress area of the tire crown while avoiding direct contact between the edge of the buffer layer and the transition area of the tire shoulder. This reduces stress superposition in the tire shoulder area caused by the excessive width of the buffer layer, lowers the probability of rubber embrittlement and cracking in low-temperature environments, and lays the foundation for the gradient width design of the outer layer of buffer fabric, further optimizing the stress dispersion effect.
[0024] 3. By using the same material as the tire carcass cord for the cushioning ply, this utility model ensures the modulus matching between the tire carcass and the cushioning layer, avoids insufficient interlayer bonding due to differences in material properties, and ensures that the same material has a consistent shrinkage rate during vulcanization, reducing the risk of interlayer delamination, simplifying the production process, reducing material compatibility issues, and improving the stability and durability of the tire structure.
[0025] 4. This utility model integrates the tire carcass cord and the cushioning cord through a vulcanization process, which strengthens the interlayer bonding strength and avoids the defects of bubbles and delamination caused by traditional layer bonding. At the same time, the edges of the cushioning cord avoid the stress concentration area of the tire shoulder, directly reducing the fatigue damage of the rubber material in the stress superposition area. Especially in low temperature environment, it can effectively inhibit the expansion of cracks from the tire shoulder to the tire crown, and significantly extend the service life of the tire under harsh agricultural conditions. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0027] Figure 2 This utility model Figure 1 Enlarged schematic diagram of part A in the middle.
[0028] Among them, 1-first layer of buffer fabric; 2-second layer of buffer fabric; 3-third layer of buffer fabric; 4-fourth layer of buffer fabric; 5-carcass fabric. Detailed Implementation
[0029] The present invention will now be described in further detail with reference to the accompanying drawings and specific preferred embodiments.
[0030] In the description of this utility model, it should be understood that the terms "left side," "right side," "upper part," "lower part," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. "First," "second," etc., do not indicate the importance of the components, and therefore should not be construed as a limitation of this utility model. The specific dimensions used in this embodiment are only for illustrating the technical solution and do not limit the protection scope of this utility model.
[0031] Reference Figure 1 , Figure 2 As can be seen, this utility model discloses a high-rigidity, puncture-resistant, and crack-resistant agricultural tire. The carcass ply 5 serves as the basic load-bearing skeleton and adopts a 3-layer reverse-wrapping structure. Four layers of narrow buffer ply are stacked radially from the inside out in the crown region. The buffer ply is located on the outside of the carcass ply 5 and the inside of the tread rubber, forming a composite structure of carcass ply, buffer ply, and tread rubber. The width of each of the four narrow buffer ply layers is smaller than the tire's running surface width and decreases radially from the inside out. The first layer of buffer ply 1 is directly attached to the crown surface of the carcass ply 5 and its width is 5mm-15mm smaller than the running surface width. The second layer of buffer ply 2 covers the outside of the first layer. The width of the first layer is 20mm-30mm less. The third layer of buffer cord 3 covers the outside of the second layer and its width is 70% of the driving surface width. The fourth layer of buffer cord 4 is the outermost layer covering the outside of the third layer and its width is 20mm-30mm smaller than the third layer. The edges of each layer of buffer cord do not overlap and all avoid the stress concentration area on the tire shoulder. The buffer cord uses the same material as the carcass cord 5. The two are integrally formed by vulcanization. At the same time, the cords of the carcass cord 5 form an angle of 53°-54° with the center line of the tire crown and have an elongation of 1.036-1.04, which together form a cohesive overall structure for bearing stress.
[0032] In one embodiment, firstly, the tire carcass ply employs a 3-layer reverse-wrapped structure to form a rigid skeleton. Combined with a 53°-54° angle between the cords and the centerline of the tire crown, and a tensile strength control of 1.036-1.04, this ensures that the direction of force on the cords aligns with the stress transmission path when the tire carcass is subjected to radial loads, thus improving overall deformation resistance. Secondly, the 4 layers of narrow buffer ply have a stepped width decreasing radially from the inside out. The first buffer ply 1 is 5mm-15mm narrower than the driving surface, the second buffer ply 2 is 20mm-30mm narrower than the first buffer ply 2, and the third buffer ply 3 is 70% of the driving surface width. The fourth layer of buffer fabric 4 is 20mm-30mm smaller than the third layer of buffer fabric 3, forming a gradient stress dispersion structure. When a sharp object punctures the tire, the outer narrow buffer fabric can absorb the impact energy through layer-by-layer deformation, avoiding instantaneous puncture caused by stress concentration. At the same time, the buffer fabric and the carcass fabric are made of the same specifications of material and are integrally formed through vulcanization process, ensuring no air bubbles or delamination defects between layers, strengthening the interface bonding strength, and forming a continuous rigid buffer barrier in the tire crown area. Combined with the design of the edges of each layer of buffer fabric avoiding the stress concentration area of the tire shoulder, the risk of puncture damage is further reduced, and the puncture resistance is significantly improved.
[0033] In one embodiment, the cord elongation value of the buffer ply is set to 1.036-1.04. This avoids problems such as insufficient cord elongation during vulcanization, cord bending, and delamination during use caused by an excessively small value, while also preventing defects such as uneven cord arrangement, bead displacement, bead deformation, and even wire breakage caused by an excessively large value. This ensures that the ply is fully stretched and the stress is evenly distributed. The crown cord angle is designed to be 53°-54°. Combined with the increased elongation design, the ratio of the tire outer diameter to the outer diameter of the tire shell after inflation is reduced from 1.026 to 1.013. This effectively curbs the expansion of the tire outer diameter and reduces the stretching of the tread rubber. Combined with the gradient width distribution of the four narrow buffer ply layers and the integrated vulcanization molding process, the stress in the crown area is made uniform, reducing stress concentration at the root of the tread. At the same time, the synergistic effect of the buffer ply and the carcass ply made of the same material further ensures the overall structural stability and improves the tire's crack resistance and fatigue resistance.
[0034] Working principle: The tire carcass ply uses a 3-layer reverse-wrapped structure to form a closed stress ring. The cords form an angle of 53°-54° with the center line of the tire crown. Combined with a cord elongation value of 1.036-1.04, the direction of force on the cords is consistent with the stress transmission path. Simultaneously, by increasing elongation and adjusting the angle, the ratio of the inflated tire outer diameter or tire shell outer diameter is reduced from 1.026 to 1.013, effectively curbing tire expansion and reducing tread rubber stretching. Four layers of narrow buffer ply are stacked radially with a stepped decrease in width. The first buffer ply 1 is 5mm-15mm narrower than the driving surface, and the second buffer ply 2 is narrower than the first… The first layer of buffer cord is 20mm-30mm smaller than the second layer, the third layer of buffer cord is 70% of the driving surface, and the fourth layer of buffer cord is 20mm-30mm smaller than the third layer of buffer cord. This creates a gradient distribution with a wider inner layer and a narrower outer layer. The edges of the fourth layer avoid the stress concentration area on the tire shoulder. When subjected to puncture or load impact, the outer buffer cord disperses energy through layer-by-layer deformation. Combined with the same material as the tire carcass cord and the vulcanization integral molding process, which ensures no air bubbles and no delamination between layers, a continuous rigid buffer barrier is formed in the tire crown area. Ultimately, this achieves uniform stress distribution on the tire carcass, reduced stress concentration, and improved puncture resistance, resulting in puncture resistance and crack prevention.
[0035] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and all such equivalent transformations fall within the protection scope of the present invention.
Claims
1. A high-rigidity, puncture-resistant, and crack-resistant agricultural tire, comprising a carcass ply (5) and a cushioning ply, characterized in that: The carcass ply (5) adopts a 3-layer reverse wrapping structure, and the buffer ply is a 4-layer narrow buffer ply, which is stacked in the crown area of the carcass ply (5) from the inside to the outside along the radial direction of the tire. The width of each of the four narrow buffer fabric layers is smaller than the width of the tire's running surface, and the width of each buffer fabric layer decreases sequentially from the inside to the outside along the tire's radial direction. The angle between the cord of the tire carcass (5) and the center line of the tire crown is 53°-54°, and the elongation value of the cord is 1.036-1.
04.
2. The high-rigidity, puncture-resistant, and crack-resistant agricultural tire according to claim 1, characterized in that, The buffer fabric includes a first buffer fabric (1), a second buffer fabric (2), a third buffer fabric (3) and a fourth buffer fabric (4). The first buffer fabric (1), the second buffer fabric (2), the third buffer fabric (3) and the fourth buffer fabric (4) are stacked. The width of the first buffer fabric (1) is 5mm-15mm smaller than the width of the tire travel surface.
3. The high-rigidity, puncture-resistant, and crack-resistant agricultural tire according to claim 2, characterized in that, The width of the second layer of buffer curtain (2) is the width of the first layer of buffer curtain (1) minus 20mm-30mm.
4. The high-rigidity, puncture-resistant, and crack-resistant agricultural tire according to claim 2, characterized in that, The width of the third buffer curtain (3) is 70% of the tire travel surface width, and the width of the fourth buffer curtain (4) is 20mm-30mm smaller than the width of the third buffer curtain (3).
5. The high-rigidity, puncture-resistant, and crack-resistant agricultural tire according to claim 1, characterized in that, The buffer curtain uses the same material as the body curtain (5).
6. The high-rigidity, puncture-resistant, and crack-resistant agricultural tire according to claim 1, characterized in that, The tire carcass cord (5) and the buffer cord are integrally formed by vulcanization, and the edges of the buffer cord avoid the stress concentration area of the tire shoulder.