Semi-steel radial tire

Abstract

The utility model relates to a kind of semi-steel radial tire, it is related to tire structure technical field, wherein bead structure is in order from inside to outside for bead core, reinforcing layer, reverse package fabric layer, positive package fabric layer and sidewall rubber;Bead core is made of apex rubber and the bead fixed in apex rubber bottom;Reinforcing layer bottom is attached with bead core, reinforcing layer top end is higher than apex rubber top end and lower than reverse package fabric layer reverse package end;The height of reverse package fabric layer reverse package end is greater than tire lower section height;Positive package fabric layer lowest point is located below bead;Sidewall rubber is covered in the outside of reverse package fabric layer and positive package fabric layer.The utility model makes the hardness of entire sidewall slowly transition from apex rubber to sidewall rubber by the aid of reinforcing layer, reduces bead stress concentration, reduces bead damage point.On this basis, by the aid of double reinforcement of reverse package fabric layer and positive package fabric layer, the overall rigidity of bead is improved, so as to improve the performance of bead under high load working condition, prolong tire service life.

Description

Technical Field

[0001] This utility model relates to the field of tire structure technology, and in particular to a semi-steel radial tire. Background Technology

[0002] Semi-steel radial tires are a type of radial tire. Their carcass cords are arranged in a radial direction, and the belt layer consists of circumferentially or nearly circumferentially arranged steel cords. They comprise six parts: tread, carcass, sidewall, belt layer, bead, and inner liner. The carcass is made of nylon or polyester fiber, and the belt layer uses steel cord fabric, combining wear resistance with low fuel consumption.

[0003] With the development of the automotive industry, various off-road vehicles have been launched, and tire companies have introduced large-specification, high-load tires to the market. These tires require high load-bearing capacity and must maintain excellent performance under various road conditions while ensuring tire protection. This places higher demands on the performance of the bead section, making it necessary to optimize the bead structure to obtain a semi-steel radial tire with superior performance under high-load conditions. Utility Model Content

[0004] To address the shortcomings of related technologies, this utility model provides a semi-steel radial tire. By setting a reinforcing layer and a positive-coated cord layer, the structural performance of the bead is improved, resulting in a semi-steel radial tire with better performance under high load conditions.

[0005] This utility model provides a semi-steel radial tire, whose bead structure, from the inside out, consists of a bead core, a reinforcing layer, a reverse-wrapped ply, a front-wrapped ply, and a sidewall rubber. The bead core is composed of a triangular rubber and a bead fixed to the bottom of the triangular rubber. The bottom of the reinforcing layer is attached to the bead core, and the top of the reinforcing layer is higher than the top of the triangular rubber but lower than the reverse-wrapped end of the reverse-wrapped ply. The height of the reverse-wrapped end of the reverse-wrapped ply is greater than the height of the tire's lower section. The lowest point of the front-wrapped ply is located below the bead.

[0006] In some embodiments, the reinforcing layer is U-shaped and covers the bead core, with the top of the reinforcing layer located outside the bead core.

[0007] In some embodiments, the height difference between the bottom of the reinforcement layer and the top of the bead is ±1 mm.

[0008] In some embodiments, the bottom end of the positive ply cord is located below the tire bead.

[0009] In some embodiments, the longitudinal distance between the top of the reinforcing layer and the top of the triangular adhesive is 10-15 mm.

[0010] In some embodiments, the difference between the height of the reverse-wrap ply reverse end and the height of the tire's lower section is 5-10 mm.

[0011] In some embodiments, the bead includes a wire ring and a covering fabric wound around the wire ring, the covering fabric being nylon cord fabric.

[0012] In some embodiments, the wrapping thickness is 0.5~0.7mm; the thickness of the reinforcing layer is 0.8~1.2mm.

[0013] In some embodiments, the height of the top of the triangular rubber is 35% to 40% of half the tire section height.

[0014] In some embodiments, the outer sidewall rubber has a rim protection structure.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. This utility model utilizes a reinforcing layer to gradually transition the hardness of the entire tire sidewall from the triangular rubber to the sidewall rubber, reducing stress concentration at the bead and minimizing potential damage points. Furthermore, the double reinforcement of the reverse and forward ply layers enhances the overall rigidity of the bead, thereby improving its performance under high-load conditions and extending tire lifespan.

[0016] 2. In this invention, since the bottom ends of the reinforcing layer and the positive-covering ply layer almost do not overlap with the inner side of the triangular rubber, the risk of exposed cords in the tire bead under heavy load conditions can be effectively avoided. Furthermore, the bottom end of the reinforcing layer is close to the apex of the bead, ensuring the connection area between the bead and the reinforcing layer, which helps to improve the connection strength between the bead and the triangular rubber. The misalignment of the bottom ends of the positive-covering ply layer and the reinforcing layer reduces the generation of air bubbles and damage points at the bead. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall tire structure in a specific embodiment of the present utility model; Figure 2 This is a schematic diagram of the tire opening in a specific embodiment of the present utility model.

[0018] In the diagram: 1. Steel wire ring; 2. Covering fabric; 3. Triangle rubber; 4. Reinforcing layer; 5. Reverse covering fabric layer; 6. Front covering fabric layer; 7. Sidewall rubber; 71. Rim protection structure.

[0019] A. Reverse end of the reverse-wrapped ply; B. Bottom end of the forward-wrapped ply; C. Top of the reinforcing layer; D. Bottom of the reinforcing layer; E. Top of the triangular rubber; H1. Height of the tire's lower section. Detailed Implementation

[0020] The technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0021] In the description of this utility model, it should be understood that the terms "center", "lateral", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" 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 element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0022] The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0023] In this utility model, the terms "high", "low", "upper", "lower" and "longitudinal distance" all refer to the difference in longitudinal height of the tire cross section, that is, the difference in radial distance of the tire.

[0024] The term "tire bottom section height" refers to the longitudinal distance from the point where the tire bottom contacts the rim support surface to the horizontal axis of the tire section. Here, the longitudinal distance refers to the radial distance difference of the tire. This horizontal axis of the tire section is located at the widest point of the tire section, where the tire carcass is thinnest and most deformable.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] like Figure 1-2As shown in the schematic embodiment of a semi-steel radial tire of this utility model, the bead structure of this semi-steel radial tire, from the inside out, consists of a bead core, a reinforcing layer 4, a reverse-wrapped ply 5, a forward-wrapped ply 6, and a sidewall rubber 7. The bead core is composed of a triangular rubber 3 and a bead fixed to the bottom of the triangular rubber 3. The bottom of the reinforcing layer 4 is attached to the bead core, and the top C of the reinforcing layer is higher than the top E of the triangular rubber and lower than the reverse-wrapped end A of the reverse-wrapped ply. The height of the reverse-wrapped end A of the reverse-wrapped ply is greater than the tire's lower section height H1. The lowest point of the forward-wrapped ply 6 is located below the bead, that is, the bottom B of the forward-wrapped ply is located below the bead or the bottom B of the forward-wrapped ply is located inside the bead core. The sidewall rubber 7 covers the outside of the reverse-wrapped ply 5 and the forward-wrapped ply 6. The starting point for calculating the height of the reverse-wrapped end A of the reverse-wrapped ply and the starting point for calculating the height of the triangular rubber top E are the same as the starting point for calculating the tire's lower section height H1.

[0027] The aforementioned tire utilizes reinforcing layer 4 to gradually transition the hardness of the entire sidewall from the triangular rubber 3 to the sidewall rubber 7, reducing stress concentration at the bead and minimizing potential damage points. Furthermore, the double reinforcement of the reverse-wrapped ply layer 5 and the forward-wrapped ply layer 6 enhances the overall rigidity of the bead, thereby improving its performance under high-load conditions and extending tire life.

[0028] In some embodiments, the reinforcing layer 4 is U-shaped and covers the bead core, with the top C of the reinforcing layer located on the outside of the bead core. The reinforcing layer 4 reinforces the outside of the bead core, reducing the deformation of the triangular rubber 3 under heavy load conditions, lowering the possibility of breakage and delamination of the triangular rubber 3, and extending the service life of the triangular rubber 3. It also reduces the possibility of bead core delamination and separation between the triangular rubber 3 and the bead, thus extending tire life.

[0029] In some embodiments, the height difference between the bottom end D of the reinforcing layer and the apex of the bead is ±1mm. In the figure, the bottom end D of the reinforcing layer is flush with the apex of the bead. Since the bottom end D of the reinforcing layer almost does not overlap with the inner side of the triangular rubber 3, the risk of exposed threads on the tire bead under heavy load conditions can be effectively avoided. Furthermore, the bottom end D of the reinforcing layer is close to the apex of the bead, ensuring the connection area between the bead and the reinforcing layer 4, which helps to improve the connection strength between the bead and the triangular rubber 3.

[0030] In some embodiments, the bottom end B of the positive wrapping fabric layer is located below the bead and is offset from the bottom end D of the reinforcing layer, reducing the generation of air bubbles and damage points at the tire bead.

[0031] In some embodiments, the longitudinal distance between the top C of the reinforcing layer and the top E of the triangular adhesive is 10-15 mm to avoid stress concentration at the sub-mouth caused by the top C of the reinforcing layer being too close to the top E of the triangular adhesive.

[0032] In some embodiments, the difference between the height of the reverse end A of the reverse ply and the height H1 of the tire lower section is 5~10mm, so that the reverse end A of the reverse ply avoids the part of the tire sidewall with the greatest flexural deformation, and avoids the problem of stress concentration and delamination at the reverse end A of the reverse ply.

[0033] In some embodiments, the thickness of the reinforcing layer 4 is 0.8~1.2mm, which can reduce the risk of delamination of the reinforcing layer 4 while ensuring the original reinforcing effect of the reinforcing layer 4.

[0034] In some embodiments, the bead includes a wire ring 1 and a covering fabric 2 wrapped around the wire ring 1, wherein the covering fabric 2 is nylon cord fabric, to further improve the structural strength and structural stability of the bead.

[0035] In some embodiments, the wrapping thickness of the fabric 2 is 0.5~0.7mm, which can reduce the risk of bead delamination while ensuring the structural strength of the bead.

[0036] Compared to a regular steel rim without nylon wrapping 2, for an LT285 / 75R16 tire (285 mm section width, 75% aspect ratio, 16-inch diameter rim, radial tire suitable for light trucks), a bead durability test was conducted. The regular steel rim passed the test in 26 hours and 31 minutes, with the failure mode being bead cracking. In contrast, the steel rim wrapped with nylon wrapping 2 passed the test in 29 hours and 25 minutes, with the failure mode being bead bulging. The bead durability performance was improved by approximately 10%, a significant improvement.

[0037] In some embodiments, the sidewall rubber 7 has a rim protection structure 71 on the outside. The rim protection structure 71 effectively resists external impacts and reduces the probability of rim damage by thickening the local area of ​​the sidewall.

[0038] In some embodiments, the height of the top E of the triangular rubber is 35% to 40% of half the tire section height. By reducing the height of the triangular rubber 3 to avoid stress concentration areas such as the rim protection structure 71, the possibility of the triangular rubber 3 breaking and the top E of the triangular rubber delamination is reduced.

[0039] The preferred embodiment of this utility model includes all the technical features of the above embodiments. For the LT285 / 75R16 specification, through conventional indoor durability testing, the test time of ordinary tires is 39 hours and 19 minutes before the bead bulge appears. However, the tire of this embodiment passes the test in 57 hours and 49 minutes under the same test conditions. The tire provided by this embodiment has a longer driving range and significantly improved durability than tires with ordinary bead structures.

[0040] Through the description of several embodiments of the semi-steel radial tire of this utility model, it can be seen that the embodiments of the semi-steel radial tire of this utility model have at least one or more of the following advantages: 1. This utility model utilizes a reinforcing layer to gradually transition the hardness of the entire tire sidewall from the triangular rubber to the sidewall rubber, reducing stress concentration at the bead and minimizing potential damage points. Furthermore, the double reinforcement of the reverse and forward ply layers enhances the overall rigidity of the bead, thereby improving its performance under high-load conditions and extending tire lifespan.

[0041] 2. In this invention, since the bottom ends of the reinforcing layer and the positive-covering ply layer almost do not overlap with the inner side of the triangular rubber, the risk of exposed cords in the tire bead under heavy load conditions can be effectively avoided. Furthermore, the bottom end of the reinforcing layer is close to the apex of the bead, ensuring the connection area between the bead and the reinforcing layer, which helps to improve the connection strength between the bead and the triangular rubber. The misalignment of the bottom ends of the positive-covering ply layer and the reinforcing layer reduces the generation of air bubbles and damage points at the bead.

[0042] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0043] The above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A semi-steel radial tire, characterized in that, The tire bead structure, from the inside out, consists of the bead core, reinforcing layer, reverse-wrapped ply, front-wrapped ply, and sidewall rubber. The bead core is composed of a triangular rubber and a bead fixed to the bottom of the triangular rubber. The bottom of the reinforcing layer is attached to the bead core, and the top of the reinforcing layer is higher than the top of the triangular rubber but lower than the reverse-wrapped end of the reverse-wrapped ply. The height of the reverse-wrapped end of the reverse-wrapped ply is greater than the height of the tire's lower section. The lowest point of the front-wrapped ply is located below the bead.

2. The semi-steel radial tire according to claim 1, characterized in that, The reinforcing layer is U-shaped and covers the bead core, with the top of the reinforcing layer located on the outside of the bead core.

3. The semi-steel radial tire according to claim 2, characterized in that, The height difference between the bottom of the reinforcement layer and the top of the bead is ±1mm.

4. The semi-steel radial tire according to claim 3, characterized in that, The bottom of the positive cord layer is located below the tire bead.

5. The semi-steel radial tire according to any one of claims 1-4, characterized in that, The longitudinal distance between the top of the reinforcing layer and the top of the triangular adhesive is 10~15mm.

6. The semi-steel radial tire according to any one of claims 1-4, characterized in that, The difference between the height of the reverse-wrap ply at the reverse end and the height of the tire's lower section is 5~10mm.

7. The semi-steel radial tire according to any one of claims 1-4, characterized in that, The tire bead consists of a steel wire ring and a covering fabric wrapped around the steel wire ring, which is made of nylon cord fabric.

8. The semi-steel radial tire according to claim 7, characterized in that, The thickness of the wrapping fabric is 0.5~0.7mm; the thickness of the reinforcing layer is 0.8~1.2mm.

9. The semi-steel radial tire according to any one of claims 1-4, characterized in that, The height of the top of the triangular rubber is 35% to 40% of half the tire cross-section height.

10. The semi-steel radial tire according to any one of claims 1-4, characterized in that, The outer sidewall of the tire has a rim protection structure.

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