Shearing-resistant pneumatic radial tire

Abstract

A cord fabric layer comprises a steel wire cord fabric II and a steel wire cord fabric III, and a rubber coating layer II is filled between the steel wire cord fabric II and the steel wire cord fabric III; the radial thickness H1 of the rubber coating layer II and the position of the center A of the bottom of the tread groove, the radial thickness H2 of the rubber coating layer II at the position of the inner end point B of the supporting rubber and the radial total thickness H3 of the rubber coating layer II and the supporting rubber at the end point C of the steel wire cord fabric have the following relations: 0.25 < = H1 / (D2 + D3) < = 0.45; h2 / H1 is greater than or equal to 1.1 and less than or equal to And 4 < = H3 / H2 < = 8. By balancing the axial size and the radial size of the center A of the bottom of the tread groove, the inner end point B of the supporting rubber and the three end points C of the steel wire cord fabric in the tire, the shear strain among the first, second, third and fourth layers and at the end points of the steel wire cord fabric is reduced, the shear strain of the crown and the shoulder of the tire is further reduced, the shear resistance of the tire is further improved, and the service life of the tire is prolonged. And the durability of the tire is improved.

Description

Technical Field

[0001] The invention relates to the technical field of tire production, and in particular to a shear-resistant pneumatic radial tire. Background Art

[0002] The tire includes a crown, a sidewall, a carcass and a bead. The intersection of the crown and the sidewall is the shoulder point, and the two sides of the crown near the shoulder point are the crown shoulders. The crown has at least three tread grooves evenly distributed along the axial direction. The crown also includes tread rubber and a belt layer combined with the tread rubber. The belt layer is radially distributed with four layers of steel cords composed of steel wires from inside to outside, which are steel cords one, two, three and four from inside to outside. The steel wires of each layer of steel cord are distributed at different angles. A rubber layer is arranged between each layer of steel cords to fill the gap. The rubber layers are rubber layer one, rubber layer two and rubber layer three from inside to outside. Secondly, the second and third end regions of the steel cord are fixedly connected with supporting rubber, the axial cross-section of which is approximately a triangle, whose upper vertex coincides with the end point of steel cord three in the radial direction of the tire, its vertex close to the shoulder point coincides with the end point of steel cord two in the radial direction of the tire, and its other vertex is close to the tread groove of the crown shoulder.

[0003] After the tire is inflated and grounded, the center of the crown contacts the ground, and then the shoulder of the crown deforms and contacts the ground under the pressure of the load. During this process, the crossed steel cords are staggered and creep deformed, causing shear strain between the steel cords and the rubber cover. With the repeated tire load deformation, the bonding force between the steel cords and the rubber cover decreases due to fatigue. When the bonding force between the two is less than the shear stress, it will cause delamination between the steel cord layers, which will lead to explosion or delamination of the crown.

[0004] The existing solution is to reduce the shear strain at the end points of the axial section of the steel cord three to avoid crown explosion or delamination. However, the inventors of the present application have found through research and analysis of a large number of tires that when the tire is deformed under load, the arrangement directions of the steel cords two and three are symmetrical about the driving direction of the tire, and their deformation trends are opposite, so that the deformation between the steel cords two and three is the largest, and thus the shear resistance of the two is the shear resistance of the tire, and thus the durability of the two is the durability of the tire. Secondly, when the tire is deformed under load, there are three stress concentration points that will cause large shear strains in the steel cords two and three and the rubber covering layer. One is the intersection A of the center of the shoulder tread groove bottom in the radial direction of the tire and the rubber covering layer, where A is the center of the tread groove bottom; one is the endpoint B of the support rubber away from the shoulder point, where B is the inner endpoint of the support rubber; and one is the endpoint C of the steel cord three on the axial section, where C is the endpoint of the steel cord three. The three stress concentration points cause two areas I and II where the steel cord is prone to separation from the rubber covering layer. The inventors of the present application found that the shear strains at various locations of the steel cords two and three are different and interrelated. Therefore, it is necessary to constrain the dimensions of the center A of the tread groove bottom, the inner endpoint B of the support rubber, and the endpoint C of the steel cord three to reduce stress concentration. Summary of the invention

[0005] The present invention provides a shear-resistant pneumatic radial tire to solve the problem of improving the durability of the crown and shoulder of the tire at the same time. The specific technical solution is as follows:

[0006] A shear-resistant pneumatic radial tire includes a cord layer, the cord layer includes a second steel cord and a third steel cord, a second rubber layer is filled between the second steel cord and the third steel cord, and the radial thickness H1 of the second rubber layer at the center A of the shoulder tread groove bottom, the radial thickness H2 of the second rubber layer at the end point B of the supporting rubber, and the radial total thickness H3 of the second rubber layer and the supporting rubber at the end point C of the third steel cord have the following relationship: 0.25≤H1 / (D2+D3)≤0.45; 1.1≤H2 / H1≤1.3; 4≤H3 / H2≤8. Among them, D2 is the thickness of the second steel cord, D3 is the thickness of the third steel cord, the center A of the tread groove bottom is the intersection of the tread groove and the second rubber layer in the radial direction of the tire, the end point B of the supporting rubber is the end point of the supporting rubber away from the shoulder point, and the end point C of the third steel cord is the end point of the third steel cord on the axial section.

[0007] Furthermore, the width of the tread groove on the tread along the tire axial direction is Gw, the distance between the center A of the tread groove bottom and the inner end point B of the supporting rubber along the tire axial direction is W1, and 0.4≤W1 / Gw≤0.8.

[0008] Furthermore, the distance between the inner end point B of the supporting rubber and the three end points C of the steel cord along the axial direction of the tire is W2, 2≤W2 / H3≤5.

[0009] Furthermore, the end point of the steel cord second close to the third end point C of the steel cord is the second end point E of the steel cord, and the distance between the third end point C of the steel cord and the second end point E of the steel cord along the axial direction of the tire is W3, 0.5≤W3 / W2≤0.8.

[0010] Preferably, the distance between the side of the tread groove intersecting with the tread and the shoulder point along the tire axial direction and the shoulder point is TL, and 0.5≤(W1+W2) / TL≤0.65.

[0011] Preferably, the distance between the shoulder points on both sides of the crown along the axial direction of the tire is TDW, the intersection point where the tread groove and the tread intersect close to the shoulder point is the tread intersection point G, the midpoint of the tread along the axial direction is the tread center M, and the radial distance between the tread intersection point G and the tread center M is Th1, 0.009≤Th1 / TDW≤0.012.

[0012] Preferably, the radial distance between the shoulder point and the tread center M is Th2, 0.06≤(Th2-Th1) / TL≤0.12.

[0013] Preferably, the maximum radial distance of the tread groove is a depth Gh, the line connecting the shoulder point and the two end points E of the steel cord intersects with the inner contour of the tire at the inner contour intersection point L, the length of the line connecting the inner contour intersection point L and the two end points E of the steel cord is L1, and the length of the line connecting the two end points E of the steel cord and the shoulder point is L2, wherein 2.4≤(L1+L2) / Gh≤3, 0.45≤L1 / L2≤0.55.

[0014] It can be seen from the above technical solution that the present invention has the following beneficial effects:

[0015] The present invention balances the axial and radial dimensions of the center A of the tread groove bottom, the inner end point B of the supporting rubber and the three end points C of the steel cord, thereby reducing the shear strain between the first, second, third and fourth layers of the steel cord and at the end points, thereby simultaneously reducing the shear strain of the crown and shoulder of the tire, thereby improving the shear resistance of the tire and thus improving the durability of the tire. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of an axial cross section of an embodiment of the present invention;

[0017] Figure 2 for Figure 1 Local structure diagram of .

[0018] In the figure: 1, steel cord fabric 1; 2, steel cord fabric 2; 3, steel cord fabric 3; 4, steel cord fabric 4; 5, rubber layer 1; 6, rubber layer 2; 7, rubber layer 3 DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in 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.

[0020] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention 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 cannot be understood as a limitation on the present invention.

[0021] like Figure 1 and Figure 2 As shown, the embodiment of the present invention includes a cord layer, and the cord layer includes in order from radial direction outward of the tire: steel cord 1, steel cord 2, steel cord 3, and steel cord 4, the thicknesses of steel cord 2 and steel cord 3 are D2 and D3 respectively, the center A of the tread groove bottom is the intersection of the tread groove of the shoulder in the radial direction of the tire and the covering rubber layer between the steel cord 2 and the steel cord 3, the inner end point B of the supporting rubber is the end point of the supporting rubber away from the shoulder point, and the end point C of the steel cord 3 is the end point of the steel cord 3 on the axial section.

[0022] Specifically, the thickness of the second and third steel cords is the diameter of the steel wires that compose them, which is the determined value of the tire steel wire, so D2 and D3 are reference values ​​for the dimensions described below. Secondly, the support rubber is fixedly connected to the ends of the second steel cord 2 and the third steel cord 3, which can limit the position of the third end point C of the steel cord relative to the shoulder point, thereby reducing the cross deformation of the third steel cord 3 at the third end point C of the steel cord when the tire is deformed under load, thereby reducing the shearing effect of the third end point C of the steel cord and the combined covering rubber, and avoiding excessive stress. Secondly, due to the large difference in rigidity between the center A of the shoulder tread groove bottom and the crown, when the tire is deformed under load, the deformation at the center A of the shoulder tread groove bottom is larger, and the cross deformation between the steel cords is large, so that its stress is more concentrated; and the steel cord three 3 is bent at the end point B inside the supporting rubber, so that the angle change is large when it crosses and deforms with the steel cord two 2, thereby making its stress more concentrated; and the end point C of the steel cord three corresponds to the shoulder point with a large deformation, so that when the tire is deformed under load, the cross deformation of the steel cord three 3 here is larger, so that the stress here is concentrated. Therefore, when the tire is deformed under load, improving the stress concentration of the center A of the tread groove bottom, the end point B inside the supporting rubber and the end point C of the steel cord three can improve the shear resistance of the tire crown and shoulder, thereby improving its durability.

[0023] Furthermore, a rubber coating layer 2 6 is filled between the steel cord 2 and the steel cord 3 3 , and the radial thickness of the rubber coating layer 2 6 at the center position A of the tread groove bottom is H1, 0.25≤H1 / (D2+D3)≤0.45, the radial thickness of the rubber coating layer 2 6 at the end point B inside the supporting rubber is H2, 1.1≤H2 / H1≤1.3, and the total radial thickness of the rubber coating layer 2 6 and the supporting rubber at the end point C of the steel cord 3 is H3, 4≤H3 / H2≤8.

[0024] Specifically, the rubber layer 26 can wrap the steel wires of the steel cords 22 and 33 corresponding to the crown, so that the rubber layer 26 can disperse the stress of the deformation of the steel cords 22 and 33 when they are cross-deformed, thereby reducing the stress concentration of the two when they are deformed. When H1 / (D2+D3)<0.25, the spacing between the steel cords 22 and 33 is too small, so that when the two are cross-deformed, the ability of the rubber layer 26 to disperse the stress is reduced, and then when the two are deformed, the stress concentration at the center A of the bottom of the tread groove is serious, which reduces the shear strain resistance of both. When H1 / (D2+D3)>0.45, the spacing between the steel cords 22 and 33 is too large and is filled by the rubber layer 26, so that the mutual restraint between the two is reduced, the rigidity of the entire crown is reduced, the deformation of the crown will increase when loaded, resulting in greater heat generation, and the thicker rubber layer 26 reduces the heat dissipation performance. The temperature increase of the crown causes its performance to decline rapidly, thereby reducing its shear strain resistance. In addition, the decrease in crown rigidity will reduce the handling performance of the tire and increase material costs. Therefore, 0.25≤H1 / (D2+D3)≤0.45 can enable the steel cord 2 and 3 to balance the shear strain resistance and heat generation and heat dissipation capabilities at the center A of the tread groove bottom to achieve maximum performance here.

[0025] Secondly, H1 is limited according to the thickness of the steel cord 2 and the steel cord 3, thereby limiting the radial thickness of the rubber layer at the center A of the tread groove bottom. The rubber layer 2 6 gradually increases from A to C, so that the end point C of the steel cord gradually approaches the shoulder point. When H2 / H1<1.1, the thickness change of the rubber layer 2 6 from the center A of the tread groove bottom to the inner end point B of the support rubber is not obvious, so that the thickness change from the inner end point B of the support rubber to the end point C of the steel cord is more obvious, thereby making the stress of the steel cord 3 3 at the inner end point B of the support rubber more concentrated when it crosses and deforms, thereby reducing the shear resistance of the steel cord 3 3 at this point. Strain capacity, when H2 / H1>1.3, the radial thickness of the rubber layer 26 at the inner end point B of the support rubber is larger, and the thickness changes significantly from the center A of the tread groove bottom to the inner end point B of the support rubber. It is easy to bend at the center A of the tread groove bottom to increase the stress concentration here. Therefore, 1.1≤H2 / H1≤1.3 can make the rubber layer 26 change from the center A of the tread groove bottom to the end point C of the steel cord, which can not only reduce the stress concentration caused by the bending of the steel cord 3 at the inner end point B of the support rubber, but also ensure that the stress concentration at the center A of the tread groove bottom is avoided due to the bending. .

[0026] Secondly, the radial distance between the three end points C of the steel cord and the tread is inversely proportional to H3. When the tire is deformed under load, the radial distance can determine its deformation degree, and then determine the magnitude of its shear strain. When H3 / H2<4, the radial distance between the three end points C of the steel cord and the tread is too large, which makes the deformation degree here too large, and then the shear strain here is too large, and then the stress concentration here is serious, and then the shear resistance at the three end points C of the steel cord decreases; when H3 / H2>8, the radial thickness of the rubber layer changes suddenly from H2 to H3, which makes the stress concentration at the inner end point B of the support rubber serious, and then reduces the shear resistance here, and then reduces the durability of the tire shoulder. Therefore, 4≤H3 / H2≤8 makes the deformation degree at the three end points C of the steel cord end points and the stress concentration at the inner end point B of the support rubber reach a balance, so that the durability of the tire shoulder and crown can reach the best.

[0027] Furthermore, the width of the tread groove on the tread along the tire axial direction is Gw, the distance between the center A of the tread groove bottom and the inner end point B of the supporting rubber along the tire axial direction is W1, and 0.4≤W1 / Gw≤0.8.

[0028] Specifically, Gw is a determined value of the tire. When W1 / Gw<0.4, the axial distance between the center A of the tread groove bottom and the inner end point B of the supporting rubber is too close, which aggravates the stress concentration at the two places, and further makes the steel cords 2 and 3 at the crown easily separate from the rubber covering layer 2 6, thereby reducing the shear strain resistance of the crown and thus reducing its durability; when W1 / Gw>0.8, the axial distance between the center A of the tread groove bottom and the inner end point B of the supporting rubber is too far, and because the Gw value is a determined value, the axial distance between the inner end point B of the supporting rubber and the end point C of the steel cord 3 is too small, which aggravates the stress concentration at the two places, thereby reducing the shear strain resistance of the shoulder and thus reducing its durability.

[0029] Furthermore, the distance between the inner end point B of the supporting rubber and the three end points C of the steel cord along the axial direction of the tire is W2, 2≤W2 / H3≤5.

[0030] Specifically, W2 and H3 jointly determine the position of the three-point C of the steel cord relative to the shoulder point. When W2 / H3<2, the transition of the steel cord three 3 from the inner end point B of the support rubber to the three-point C of the steel cord is large, which intensifies the stress concentration of the inner end point B of the support rubber, and the two points are too close to each other, which intensifies the stress concentration in the area near the shoulder of the crown, thereby increasing the shear strain of the steel cord three 3 and the rubber layer two 6, thereby reducing the durability here; when W2 / H3>5, the three-point C of the steel cord is too close to the shoulder point, so that when the tire is deformed under load, its deformation in the radial direction is large, thereby intensifying the stress concentration of the three-point C of the steel cord at the shoulder point, thereby increasing the shear strain here, thereby reducing the durability of the shoulder.

[0031] Furthermore, the end point of the steel cord 2 close to the third end point C of the steel cord is the end point E of the steel cord 2, and the distance between the third end point C of the steel cord and the end point E of the steel cord 2 along the axial direction of the tire is W3, 0.5≤W3 / W2≤0.8.

[0032] Specifically, W3 / W2 is used to constrain the spacing between the end points of steel cord 2 and steel cord 3, thereby balancing the tire deformation pressure on steel cord 2 and steel cord 3. When W3 / W2<0.5, the axial spacing between the end point E of the steel cord 2 and the end point C of the steel cord is too close, resulting in stress concentration at the end points of steel cord 2 and steel cord 3, where shear deformation is relatively large, and the shear deformation capacity of steel cord 2 to share the area of ​​end point C of steel cord 3 is reduced, thereby reducing the durability of the tire shoulder; when W3 / W2>0.8, the end point E of the steel cord 2 is limited to the distance to the sidewall and cannot be too small, otherwise it is easy to cause the deformation zone buffer zone between the end point E of the steel cord 2 and the sidewall to be too small, thereby causing cracks in the sidewall area when the tire is deformed under load, thereby reducing the durability of the tire.

[0033] Furthermore, the intersection point where the tread groove intersects the tread and is close to the shoulder point is the tread intersection point G, and the distance between the tread intersection point G and the shoulder point along the tire axial direction is TL, 0.5≤(W1+W2) / TL≤0.65.

[0034] Specifically, W1+W2 represents the relative distance between the three end points C of the steel cord and the center A of the bottom of the shoulder tread groove in the tire axial direction. When (W1+W2) / TL<0.5, the total axial width of the steel cord 3 is too small, the three end points C of the steel cord, the inner end point B of the support rubber and the center A of the bottom of the tread groove are too concentrated, and the shear stress cannot be dispersed, thereby reducing the durability. On the other hand, the support of the steel cord 3 to the shoulder is reduced, thereby reducing the rigidity of the shoulder; when (W1+W2) / TL>0.65, the three end points C of the steel cord are too close to the shoulder point, so that the radial deformation increases when the tire is deformed under load, thereby increasing the shear strain of the steel cord 3, thereby reducing its durability.

[0035] Furthermore, the axial distance between the shoulder points on both sides of the crown is TDW, the intersection point where the tread groove and the tread intersect close to the shoulder point is the tread intersection point G, the midpoint of the tread along the axial direction is the tread center M, and the radial distance between the tread intersection point G and the tread center M is Th1, 0.009≤Th1 / TDW≤0.012.

[0036] Specifically, TDW is the determined value of the tire, the tread center M is the point with the largest radial radius of the tread, that is, it contacts the ground first, and Th1 represents the radial deformation of the tread intersection G when the tire is deformed under load, which in turn reflects the magnitude of the shear strain on the crown. When Th1 / TDW<0.009, the tread intersection G and the tread center M are approximately horizontal after the tire is inflated, so that after the tire is deformed under load, the pressure between the tread intersection G and the ground is approximately equal to the pressure on the tread center M, and the pressure between the crown shoulder and the ground is then excessively shared by the tread intersection G, resulting in uneven pressure distribution and insufficient shoulder pressure, which leads to severe wear of the crown shoulder and reduces its service life; when Th1 / TDW>0.012, when the tire is deformed under load, the radial deformation of the tread intersection G is too large, which makes the cross deformation of the steel cords 1, 2, 3, 4 too large, and thus causes excessive shear strain, thereby reducing the durability of the crown.

[0037] Further, the radial distance between the shoulder point and the tread center M is Th2, 0.06≤(Th2-Th1) / TL≤0.12.

[0038] Specifically, Th2-Th1 represents the radial deformation of the shoulder point compared to the tread intersection G. When Th2-Th1<0.06, the shoulder point is too close to the ground, so that when the tire is deformed under load, the pressure between the shoulder point and the ground increases, making the shoulder prone to rapid wear and reducing the service life of the shoulder; when Th2-Th1>0.12, when the tire is deformed under load, the radial deformation of the shoulder point is too large, which increases the cross deformation of the steel cord 2 and the steel cord 3, causing the shear strain to be too large, thereby reducing the durability of the shoulder.

[0039] Furthermore, the maximum distance of the tread groove in the radial direction is the depth Gh, the line connecting the shoulder point and the end point E of the steel cord intersects with the inner contour of the tire at the inner contour intersection point L, the length of the line connecting the inner contour intersection point L and the end point E of the steel cord is L1, and the length of the line connecting the end point E of the steel cord and the shoulder point is L2, wherein 2.4≤(L1+L2) / Gh≤3, 0.45≤L1 / L2≤0.55.

[0040] Specifically, Gh is the determined value of the tread groove, (L1+L2) / Gh represents the thickness of the shoulder point along the L1 direction, when (L1+L2) / Gh<2.4, the crown shoulder is too thin, so that when its load contacts the ground, there is a lack of sufficient support for the tread, and insufficient pressure causes rapid wear of the shoulder. When (L1+L2) / Gh>3, the crown shoulder is too thick, so that its heat dissipation ability decreases, thereby reducing the rubber performance at the shoulder, thereby reducing the load-bearing capacity of the shoulder.

[0041] Secondly, L1 / L2 indicates the position of the end point E of the steel cord 2 relative to the shoulder point. When L1 / L2<0.45, the end point E of the steel cord 2 is too far from the shoulder point, and the corresponding steel cord 3 will also be far away from the shoulder point under the fixation of the support rubber, so that when the tire is loaded and deformed, the radial deformation of the end point C of the steel cord 3 and the end point B inside the support rubber will increase, the corresponding shear strain will increase, and the durability of the crown and shoulder will decrease; when L1 / L2>0.55, the end point E of the steel cord 2 is too close to the shoulder point. Under the fixation of the support rubber, the corresponding steel cord 3 will be closer to the tread of the shoulder part, affecting the retreading performance of the tire.

[0042] Examples 1 to 33 and Comparative Examples 1 to 3

[0043] A pneumatic radial tire (British specification: 12R22.5) was manufactured, the diameters of the second and third steel cords were D2=D3=1.1 mm, and the shear strain indexes of the tread groove bottom center A, the inner end point B of the support rubber, and the end point C of the third steel cord were measured by the following method.

[0044] Table 1

[0045]

[0046]

[0047] Note: The larger the shear strain index is, the greater the shear force on the ends of the steel cord is, and the more likely the tire is to be damaged due to insufficient durability.

[0048] Through Examples 1, 2, 3 and Comparative Example 2, it is found that as H1 / (D2+D3) increases, the shear strains at A and B decrease, and the shear strain at C remains basically unchanged. However, when H1 / (D2+D3)≥0.45, the shear strains at A and B remain basically unchanged, and the gain becomes lower. An excessively thick rubber coating layer 26 will weaken the restraining effect of the belt layer on the carcass, reduce the rigidity of the entire tire, reduce wear, and is not conducive to the handling performance of the tire. Therefore, it is preferred to take 0.25≤H1 / (D2+D3)≤0.45.

[0049] On the other hand, the distribution positions at A and B are reasonably distributed to avoid the amplification effect caused by the concentration of stress points. As shown in Table 1, the shear strains at A and B are significantly reduced in Example 4 relative to Comparative Example 1. It can be seen from Examples 4, 2, and 5 that when W1 / Gw increases, the shear strain at A is significantly reduced, but the gain is on a downward trend, and the shear strain at B increases slightly. When W1 / Gw>0.8, considering the shear strain change trend at A / B, the gain is significantly reduced. It is preferred to take 0.4≤W1 / Gw≤0.8. Furthermore, in order to ensure a smoother transition between A and C in the radial thickness H2 of the rubber coating layer 6, it is preferred to take 1.1≤H2 / H1≤1.3.

[0050] Table 2

[0051]

[0052] Furthermore, the shape trend of the supporting rubber should satisfy 4≤H3 / H2≤8, 2≤W2 / H3≤5. While reducing the radial distance of C relative to the midpoint M of the tread, the transition of the steel cord 3 from C to B is smoother, and the shear stress distribution is more dispersed. As shown in Table 2, through comparative example 2, examples 7, 8, and 9, it can be seen that with the increase of H3 / H2, the shear strain at C shows a significant decreasing trend, but the profit trend is gradually decreasing. Combined with the shear strain at B, which is increasing slightly, 4≤H3 / H2≤8 is preferably taken for the best comprehensive benefit. Through examples 10, 11, 8, and 12, as W2 / H3 increases, the shear strain at B shows a significant decreasing trend, but the profit trend is gradually decreasing. At the same time, the shear strain at C has the opposite trend, so for the best comprehensive benefit, 2≤W2 / H3≤5 is preferably taken.

[0053] Table 3

[0054]

[0055] Specifically, as shown in Table 3, in Examples 17, 14, 18, and 19, as (W1+W2) / TL increases, the shear strain at C increases significantly, and the comprehensive shoulder rigidity increases (excellent anti-eccentric wear performance), preferably 0.50≤(W1+W2) / TL≤0.65. In addition, as W3 / W2 increases, the difference between the steel cord 2 and the steel cord 3 increases. On the one hand, the three end points C of the steel cord are far away from the shoulder deformation area, and on the other hand, the supporting and protective effect of the steel cord 2 is strengthened, and the shear strain at the three end points C of the steel cord is significantly reduced, but it will cause deformation interference in the areas of A and B, and the shear strain has a tendency to increase, as shown in Table 3, the results of Examples 13, 14, 15, and 16, and based on the principle of comprehensive maximum benefit, it is preferably 0.5≤W3 / W2≤0.8.

[0056] Table 4

[0057]

[0058] Specifically, as shown in Table 4, in Examples 20, 21, 22, and 23, the smaller (Th2-Th1) / TL is, and in Examples 21, 24, 25, and 26, the smaller Th1 / TDW is, the smaller the radial difference at each location of the tread profile is, and the shear strain at each characteristic point A, B, and C is smaller. However, when the ratio is too small, the growth of the contact patch shoulder is too large, and during rolling, the contact pressure of the shoulder is too large, which can easily cause rapid wear of the shoulder and the occurrence of abnormal shoulder wear. The preferred principle of maximizing comprehensive benefits is 0.06≤(Th2-Th1) / TL≤0.12 and 0.009≤Th1 / TDW≤0.012.

[0059] Table 5

[0060]

[0061] Specifically, as shown in Table 5, Examples 27, 28, 29, and 30, by increasing the ratio of Ln1 / Ln2, the deformation of the end point C of 3B under the rolling load of the tire is reduced, and the shear strain is reduced, and the shear strain at B and C is slightly reduced, but an excessively large ratio of Ln1 / Ln2 will cause the end point of the belt layer to be too close to the tread profile, affecting the retreading performance of the tire. As shown in Table 5, Examples 31, 28, 32, and 33, by controlling the ratio of (Ln1+Ln2) / Gh, the ground contact performance is balanced while reducing the shear strain and heat generation, and preferably 2.4≤(Ln1+Ln2) / Gh≤3.0.

[0062] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0063] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A shear-resistant pneumatic radial tire, comprising a cord layer and a shoulder point, the shoulder point being the intersection of the crown and the sidewall, characterized in that: The cord layer comprises a second steel cord (2) and a third steel cord (3), a second rubber layer (6) is filled between the second steel cord (2) and the third steel cord (3), and the radial thickness H1 of the second rubber layer (6) at the center A of the tread groove bottom, the radial thickness H2 of the second rubber layer (6) at the end point B inside the supporting rubber, and the radial total thickness H3 of the second rubber layer (6) and the supporting rubber at the end point C of the third steel cord are as follows: 0.25≤H1 / (D2+D3)≤0.45; 1.1≤H2 / H1≤1.3; 4≤H3 / H2≤8; Wherein, D2 is the thickness of the steel cord fabric 2 (2), D3 is the thickness of the steel cord fabric 3 (3), the center A of the bottom of the tread groove is the intersection of the tread groove of the crown shoulder and the rubber layer 2 (6) in the radial direction of the tire, the inner end point B of the supporting rubber is the end point of the supporting rubber away from the shoulder point, and the end point C of the steel cord fabric 3 is the end point of the steel cord fabric 3 (3) in the axial section.

2. The shear-resistant pneumatic radial tire according to claim 1, characterized in that: The width of the tread groove on the tread along the tire axis is Gw, and the distance between the center A of the tread groove bottom and the inner end point B of the supporting rubber along the tire axis is W1, 0.4≤W1 / Gw≤0.

8.

3. The shear-resistant pneumatic radial tire according to claim 2, characterized in that: The distance between the inner end point B of the supporting rubber and the third end point C of the steel cord fabric along the axial direction of the tire is W2, 2≤W2 / H3≤5.

4. The shear-resistant pneumatic radial tire according to claim 3, characterized in that: The end point of the steel cord second (2) close to the end point C of the steel cord third (3) is the end point E of the steel cord second (2), and the distance between the end point C of the steel cord third (3) and the end point E of the steel cord second (2) along the axial direction of the tire is W3, 0.5≤W3 / W2≤0.

8.

5. The shear resistant pneumatic radial tire according to claim 4, characterized in that: The intersection point of the tread groove and the tread close to the shoulder point is the tread intersection point G, and the distance between the tread intersection point G and the shoulder point along the tire axial direction is TL, 0.5≤(W1+W2) / TL≤0.

65.

6. The shear-resistant pneumatic radial tire according to claim 5, characterized in that: The distance between the shoulder points on both sides of the crown along the axial direction of the tire is TDW, the midpoint of the tread along the axial direction is the tread center M, the radial distance between the tread center M and the tread intersection G is Th1, 0.009≤Th1 / TDW≤0.

012.

7. The shear resistant pneumatic radial tire according to claim 6, characterized in that: The radial distance between the shoulder point and the tread center M is Th2, 0.06≤(Th2-Th1) / TL≤0.

12.

8. The shear resistant pneumatic radial tire according to claim 1, characterized in that: The maximum radial distance of the tread groove is a depth Gh, a line connecting the shoulder point and the second (2) end point E of the steel cord intersects with the inner contour of the tire at the inner contour intersection point L, a length of a line connecting the inner contour intersection point L and the second (2) end point E of the steel cord is L1, a length of a line connecting the second (2) end point E of the steel cord and the shoulder point is L2, wherein 2.4≤(L1+L2) / Gh≤3, 0.45≤L1 / L2≤0.55.

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