A radial aircraft tire crown belt ply structure and a radial aircraft tire

Abstract

This invention relates to a radial aircraft tire crown belt structure and a radial aircraft tire. The radial aircraft tire crown belt structure includes: a reinforcing ply, a carcass layer, and a crown region; the reinforcing ply includes: a first belt layer, a second belt layer, and a third belt layer. In this embodiment, the first belt strip is wound circumferentially at a near-zero angle in a spiral manner. The circumference of each layer is set to s*n+(1 / 6-1 / 2)n, that is, the first layer of the layered structure is wound from point O to point D in a second direction, and then wound for n / 4 more to reach point F. Then, the second layer of the layered structure is wound from point F in the opposite direction to the second direction to point G. Then, the third layer of the layered structure is wound sequentially from point G to point H in an axial direction. The fourth layer of the layered structure is wound from point H to point O. This configuration of the first belt layer allows for a more uniform width of the first belt layer wound at each position in the carcass layer, making the first belt layer more stable in terms of stress and other aspects.

Description

Technical Field

[0001] This invention relates to a radial aircraft tire crown belt structure and a radial aircraft tire. Background Technology

[0002] Currently, during aircraft takeoff and landing, under high load and high speed conditions, the tread and sidewall areas of radial aircraft tires experience severe compression deformation in contact with the ground. When entering and leaving the contact patch, the tread area undergoes significant flexing. Tires leaving the ground at high angular acceleration and velocity tend to stretch radially outwards. During high-speed rolling, uneven distribution of the belt layer width along the tire circumference can lead to delamination, tearing, and serious aircraft tire quality accidents.

[0003] Figure 4 The diagram illustrates the unfolded structure of the first belt layer in the prior art. Points O, E, D, and C are all located on a first straight line extending axially, while points M and N are located on a second straight line. The first and second straight lines are symmetrically arranged about the tire's axis. In the prior art, the first layer of the layered structure winds from point O to point D in a second direction (axial direction). Then, the second layer of the layered structure winds from point C to point E in the opposite direction (axial direction). The third layer of the layered structure then winds sequentially from point O to point D in the axial direction. The fourth layer of the layered structure winds from point C to point E, and so on for the fifth and sixth layers. This arrangement of the first belt layer structure results in the width of the first layer on the first straight line being from point O to point C, and the width of the second layer on the second straight line being from point M to point N. The length of OC is greater than the length of MN, causing uneven width of the first belt layer at each position on the tire carcass, leading to changes in the stress and other aspects of the first belt layer. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that the belt layer in existing radial aircraft tires is not uniformly wide at each position of the tire carcass.

[0005] To address the aforementioned technical problems, the present invention provides a radial aircraft tire crown belt structure, comprising: a reinforcing ply layer, a carcass layer, and a crown region; the reinforcing ply layer is disposed between the carcass layer and the crown region; the reinforcing ply layer comprises: a first belt layer, a second belt layer, and a third belt layer; the first belt layer is disposed on the carcass layer, the third belt layer is disposed on the first belt layer, and the second belt layer is disposed on the third belt layer;

[0006] Both the first belt layer and the third belt layer are composed of multiple layered structures stacked in the radial direction; the winding directions of two adjacent layered structures are opposite in the axial direction; the layered structure is formed by spirally winding the first belt strip around the tire carcass layer s times; the circumference of the first belt strip around the tire carcass layer for each turn is n; the circumference of the first belt strip is s*n+(1 / 6-1 / 2)n.

[0007] In this structure, the layer closer to the carcass is the first layer, and the layer further away from the carcass is the second layer; the second layer is wound in the opposite direction starting from the end of the first layer.

[0008] Optionally, the first belt layer, the third belt layer, and the belt layer are all composed of a first belt strip spiral; the width of the first belt layer is greater than the width of the third belt layer, the width of the second belt layer is greater than the width of the third belt layer, and less than the width of the first belt layer.

[0009] Optionally, the perimeter of the first belt strip is s*n+1 / 4n.

[0010] Optionally, the width of the first belt strip is b; the angle between the first belt strip and the circumferential direction is α; the first belt strip has a first side and a second side that are parallel to each other; for every half turn of the first belt strip around the tire carcass, the first belt strip is offset by b / 2cosα along the first direction; for every full turn of the first belt strip around the tire carcass, the first belt strip is offset by b / cosα along the first direction; the first direction is parallel to the axial direction.

[0011] Optionally, the first belt strip is formed by extruding and coating multiple fiber skeletons; the multiple fiber skeletons are arranged at equal intervals and parallel to each other.

[0012] Optionally, the adhesive-coated area in the cross-section of the first belt strip is S-adhesive, and the area of ​​the fiber skeleton in the cross-section of the first belt strip is S-line; S-adhesive:S-line = 1.0-1.5 times.

[0013] Optionally, the fiber skeleton of the first and third belt layers is selected from 1500D1×4 aramid, with a breaking strength ≥1400N and a breaking elongation of 3.5±1.5%; the fiber skeleton of the second belt layer is selected from 2800dtex / 3N66, with a breaking strength ≥690N and a breaking elongation of 26±3.0%.

[0014] Optionally, the first belt layer has 4-6 layers; the second belt layer has 4-6 layers; and the third belt layer has 2-4 layers.

[0015] Optionally, the second belt layer is wound around the first belt layer in a "Z" shape.

[0016] A radial aircraft tire comprising: a radial aircraft tire crown belt structure as described in any of the preceding claims.

[0017] The advantages of the radial aircraft tire crown belt layer structure and radial aircraft tire of this invention compared with the prior art are as follows:

[0018] In this embodiment of the invention, the circumference of the first belt strip is set to s*n+(1 / 6-1 / 2)n, that is, the first layer of the layered structure is wound from point O to point D in the second direction (axial direction) and then wound for more than n / 4 to reach point F. Then the second layer of the layered structure is wound from point F in the opposite direction to the second direction (axial direction) to point G. Then the third layer of the layered structure is wound from point G to point H in the axial direction. The fourth layer of the layered structure is wound from point H to point O. This configuration of the first belt layer makes the width of the first belt layer more uniform at each position of the carcass layer, and makes the first belt layer more stable in terms of stress and other aspects. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view of an embodiment of the present invention;

[0020] Figure 2 This is a cross-sectional view of the first belt strip in an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram showing the unfolded shape of the first belt strip in an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the first layered structure of the first belt layer in the prior art;

[0023] Figure 5 This is a schematic diagram of the first layered structure of the first belt layer in an embodiment of the present invention;

[0024] Figure 6 This is a schematic diagram of the second layered structure of the first belt layer in an embodiment of the present invention;

[0025] Figure 7 This is a schematic diagram of the third layered structure of the first belt layer in an embodiment of the present invention;

[0026] Figure 8 This is a schematic diagram of the fourth layer structure of the first belt layer in an embodiment of the present invention.

[0027] In the diagram, 1 is the reinforcing ply layer; 11 is the first belt layer; 12 is the second belt layer; 13 is the third belt layer; 14 is the first belt strip; 141 is the fiber skeleton; 2 is the carcass layer; and 3 is the crown area. Detailed Implementation

[0028] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0029] First, it should be noted that the directions such as top, bottom, upward, and downward mentioned in this article are defined relative to the directions in the various accompanying figures. They are relative concepts and therefore can change depending on their different positions and practical applications. Therefore, these or other directions should not be interpreted as restrictive terms.

[0030] It should be noted that the term "comprising" does not exclude other elements or steps, and "a" or "an" does not exclude the plural.

[0031] Furthermore, it should be noted that any single technical feature described or implied in the embodiments herein, or any single technical feature shown or implied in the accompanying drawings, can still be combined among these technical features (or their equivalents) to obtain other embodiments of this application not directly mentioned herein.

[0032] It should also be understood that while the terms "first," "second," etc., are used in this document to describe various types of information, this information should not be limited to these terms, which are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information.

[0033] It should be noted that in different figures, the same reference numerals denote the same or substantially the same components.

[0034] In this application, "carcass layer" refers to the tire skeleton material structure excluding the belt reinforcement structure, bead, tread, and sidewall rubber. "Circumferential" refers to a line or direction extending perpendicular to the axial direction along the circumference of the surface of the annular tread. "Axial" refers to a line or direction parallel to the tire's axis of rotation. "Equatorial plane (EP)" refers to a plane perpendicular to the tire's axis of rotation and passing through the center of its tread. "Cord layer" refers to a continuous layer of rubber coating, preferably with parallel cords. "Radial" refers to a direction radially toward or away from the tire's axis of rotation. "Radial tire" refers to a belted or circumferentially restricted pneumatic tire, wherein the cords extending from the bead to the bead are arranged at a cord angle between 80° and 90° relative to the tire's equatorial plane.

[0035] like Figure 1 As shown in the preferred embodiment of the present invention, a radial aircraft tire crown layer structure includes: a reinforcing ply layer, a carcass layer, and a crown region. The reinforcing ply layer is disposed between the carcass layer and the crown region. Figure 1 The image shows the tire cross-section, with the entire tire being symmetrical about the equatorial plane EP.

[0036] See Figure 1 The reinforcing ply includes a first belt layer, a second belt layer, and a third belt layer. The first belt layer is disposed on the carcass layer, the third belt layer is disposed on the first belt layer, and the second belt layer is disposed on the third belt layer.

[0037] Both the first belt layer and the third belt layer are composed of multiple layered structures stacked in the radial direction; the winding directions of two adjacent layered structures are opposite in the axial direction; the layered structure is formed by spirally winding the first belt strip around the tire carcass layer s times; the circumference of each winding of the first belt strip around the tire carcass layer is n; the first belt strip is spirally wound around the tire carcass layer at an angle close to zero, and the circumference of each layer is set as s*n+(1 / 6-1 / 2)n.

[0038] In this structure, the layer closer to the carcass is the first layer, and the layer further away from the carcass is the second layer; the second layer is wound in the opposite direction starting from the end of the first layer.

[0039] Figure 4 The diagram illustrates the unfolded structure of the first belt layer in the prior art. Points O, E, D, and C are all located on a first straight line extending axially, while points M and N are located on a second straight line. The first and second straight lines are symmetrically arranged about the tire's axis. In the prior art, the first layer of the layered structure winds from point O to point D in a second direction (axial direction). Then, the second layer of the layered structure winds from point C to point E in the opposite direction (axial direction). The third layer of the layered structure then winds sequentially from point O to point D in the axial direction. The fourth layer of the layered structure winds from point C to point E, and so on for the fifth and sixth layers. This arrangement of the first belt layer structure results in the width of the first layer on the first straight line being from point O to point C, and the width of the second layer on the second straight line being from point M to point N. The length of OC is greater than the length of MN, causing uneven width of the first belt layer at each position on the tire carcass, leading to changes in the stress and other aspects of the first belt layer.

[0040] Therefore, based on the above issues, see Figures 4-8 The structure of this application is achieved by setting the perimeter of the first belt strip to s*n+(1 / 6-1 / 2)n, see [link to relevant documentation]. Figure 5 That is, the first layer of the layered structure winds from point O to point D in the second direction (axial direction), and then winds another n / 4 to reach point F. See [link to relevant documentation]. Figure 6 Then the second layer of layered structure wraps from point F in a direction opposite to the second direction (axial direction) to point G, see [link / reference]. Figure 7 Then the third layer of the layered structure is wound axially from point G to point H, see [reference needed]. Figure 8 The fourth layer of the layered structure winds from point H to point O. This design allows the first belt layer to be wound more evenly at each position of the carcass layer, making the first belt layer more stable in terms of stress and other aspects.

[0041] Furthermore, the second belt layer is wound in a "Z" shape around the first belt layer. The second belt layer enhances the clamping coefficient of the tire crown and restricts the radial expansion of the tire. The radial outer layer of the second belt layer is wound in a Z shape, which serves two purposes: first, to buffer the interlayer transition between the first belt layer and the tire crown layer; and second, to increase the lateral stiffness of the aircraft tire during inflation and optimize the cornering characteristics of the aircraft tire.

[0042] Furthermore, the first belt layer, the third belt layer, and the belt layer are all composed of a first belt strip spiral; the width of the first belt layer is greater than the width of the third belt layer, and the width of the second belt layer is greater than the width of the third belt layer but less than the width of the first belt layer. Item 11 shown is the first belt layer, with 2-8 winding layers, preferably 4-6 layers, a width of W1, and a winding layer number of n1, where n1 is preferably an even number. According to the conventional 15-23 inch radial aircraft tire structure design, the main belt layer typically has 2-8 winding layers. If the number of winding layers is too small, the design strength is insufficient, and the load-bearing capacity decreases; if the number of winding layers is too large, increasing the weight of the aircraft tire is not advisable given that the strength design has already been met. Item 12 shown is a "Z"-shaped winding layer, with 2-4 winding layers, preferably 2 layers, a width of W2, and a winding layer number of n2. The number 13 shown is the third belt layer, with 2-4 winding layers, preferably 2 layers, and its width is W3. The number of winding layers is n3, and n3 is preferably an even number.

[0043] Among them, W1 > W2 > W3

[0044] Furthermore, the width relationship exists as W1:W2:W3 = (2-1.5):(1.5-1.2):1, with the preferred width being W1:W2:W3 = (1.8-1.6):(1.4-1.3):1.

[0045] And there exists: n1+n3=(2-4)n2, preferably n1+n3=3n2.

[0046] Further, see Figure 2The first belt strip is formed by extruding and coating multiple fiber skeletons; the multiple fiber skeletons are equidistant and parallel. The first belt strip is obtained by extrusion and is formed by coating multiple parallel and equidistantly arranged fiber skeleton materials. The fiber skeletons are located at the geometric center of the belt strip's cross-section, and the amount of coating on the top and bottom is equal. The width of the first belt strip's cross-section is W, the thickness is B, the fiber skeleton diameter is D, the fiber skeleton spacing is K, the distance from the center of the outermost fiber skeleton to the edge of the belt strip is P, and the number of fiber cords in the belt strip satisfies the formula:

[0047] n = (W - 2P) / K + 1;

[0048] 4≤n≤12, preferably 6≤n≤10;

[0049] P = (0.6-1.0)D, preferably P = (0.7-0.8)D;

[0050] K = (1.1-1.6)D, preferably K = (1.2-1.4)D;

[0051] The thickness of the first belt strip satisfies: B = (1.1-1.6)D, preferably B = (1.2-1.4)D.

[0052] When the value of n is too small, the total width W of the first belt strip cross section is small, resulting in a decrease in the spiral or "Z"-shaped winding efficiency of the radial aircraft tire belt strip. When the value of n is too large, the total width W of the first belt strip is large, resulting in an increase in the circumferential angle of the radial aircraft tire spiral belt strip. During the "Z"-shaped winding process, when it is necessary to turn back and wind in the opposite direction within the total winding width range, the bending will cause the cord to fold, making it difficult to achieve a good winding effect.

[0053] If the values ​​of P and K are too large, the overall adhesive coverage of the belt strip increases. When two or more belt strips are placed side by side, the center-to-center distance between the adjacent fiber skeleton material cords becomes too large, causing the fiber skeleton to split. If the values ​​of P and K are too small, the overall adhesive coverage of the first belt strip decreases. When two or more first belt strips are placed side by side, the center-to-center distance between the adjacent fiber skeleton material cords becomes too small, causing the fiber skeleton to concentrate in this area.

[0054] The optimal value for B is (1.2-1.4)D. If the value is too large, it will increase the amount of rubber coating on the first belt strip, which will affect the lightweight design of the aircraft tire. If the value is too small, the amount of rubber coating on the top and bottom will be too small, resulting in thin rubber coating, reduced rubber coating quality, and exposed rubber lines due to extrusion.

[0055] If the ratio of S-rubber to S-line is small, the amount of rubber coating decreases, and the belt strip obtained by extrusion is prone to rubber coating quality problems, such as thinness, uneven rubber coating, surface pitting, and exposed fibers. If the ratio of S-rubber to S-line is too large, the amount of rubber coating increases, the thickness of the belt strip obtained by extrusion increases, and the belt strip winding increases the tire weight, affecting the lightweight design of radial aircraft tires. Limiting the amount of rubber coating on the belt strip during extrusion can achieve lightweight tires. Therefore, in the cross-section of the belt strip, serial number 141 is the fiber cord with a cross-sectional area of ​​S, and serial number 4 is the amount of rubber coating with a cross-sectional area of ​​S-rubber, which satisfies the following:

[0056] S-resin: S-line = 1.0-1.5 times, preferably 1.1-1.2 times;

[0057] Furthermore, the fiber skeleton of the first and third belt layers is selected from 1500D1×4 aramid, with a breaking strength ≥1400N and a breaking elongation of 3.5±1.5%; the fiber skeleton of the second belt layer is selected from 2800dtex / 3N66, with a breaking strength ≥690N and a breaking elongation of 26±3.0%.

[0058] Further, see Figure 3 The width of the first belt strip is b. The angle between the first belt strip and the circumferential direction is α. The first belt strip has a first side and a second side that are parallel to each other. For every half turn of the first belt strip around the tire carcass, the first belt strip shifts along a first direction by b / 2cosα; for every full turn of the first belt strip around the tire carcass, the first belt strip shifts along a first direction by b / cosα, where the first direction is parallel to the axial direction.

[0059] The difference between the maximum and minimum width of the belt layer is the axial width b / cosα of the belt strip. For radial aircraft tires, the smaller the specification and the smaller the tire diameter, the greater the rate of change in stress on the belt layer. At the tread position where the widest belt layer is located, under the same internal pressure and load, the tire's lateral stiffness is higher than that at the tread position where the narrowest belt layer is located. With increasing belt layer width, the radial stiffness, lateral stiffness, and torsional stiffness of the radial aircraft tire all increase. Radial stiffness directly affects the landing gear's landing cushioning performance and shimmy stability; lateral stiffness directly affects the dynamic lateral slip characteristics of the wheels, impacting the handling stability of high-speed taxiing aircraft. Under such alternating lateral and radial stiffness stresses, a high-speed rotating aircraft tire will quickly experience serious quality and safety incidents such as shoulder detachment, tread separation, and belt layer bursting.

[0060] Figure 3This diagram illustrates a belt strip displayed on a belt drum during helical winding. The belt strip width is b, the winding starts at line aa, line AB is perpendicular to line aa, after one revolution the belt strip overlaps at positions A and B, the belt drum radius is R, and the winding angle of the belt strip satisfies:

[0061] α = arc sin(b / 2πR);

[0062] 6mm≤b≤14mm, preferably 8mm≤b≤10mm;

[0063] 300mm≤R≤700mm (including most aircraft tire specifications);

[0064] The range of values ​​for 'a' is: 0.10°≤a≤0.3°, preferably: 0.13°≤a≤0.24°;

[0065] With a constant R, b is directly proportional to the sine function of the winding angle α. The larger the value of b, the larger the winding angle α, and the larger the angle between the unwound belt and the circumferential direction. The more inclined the belt is, the smaller the circumferential stress decomposition value Fcosα of the cord decreases during the inflation of the aircraft tire, resulting in an increase in the radial expansion of the aircraft tire. To ensure that the radial expansion of the radial aircraft tire approaches zero, the belt width b should be minimized.

[0066] In this study, tires of the H44.5×16.5R21 specification shown in Table 1 were used. The tread durability performance index was determined for the tires according to the comparative examples and embodiments of the present invention under the specifications shown in Table 1. Specifically, the rim assembly with the tire mounted on a dedicated rim was repeatedly rotated for 10 minutes at a speed of 64 km / h under a specified load on a durability testing machine, and quality problems such as delamination at the tread area were evaluated. The index was measured and displayed for each tire; the higher the index value, the better the tread area separation durability.

[0067] Analysis of the test results shows that for this specification of aircraft tire, the separation durability of the crown area of ​​Comparative Example 1 is 100. This construction is a standard design for radial aircraft tires. The width of the belt layer decreases progressively from radial to outward. The main and auxiliary belt layer materials are 2800dtex / 3N66, with no clear distinction between main and auxiliary belt layers. The breaking strength is ≥690N, and the elongation at break is 26±3.0%. The expansion rate of this comparative example tire reaches 5.56%. After completing a total of 8 belt layers, 2 additional belt layers were added due to strength issues. The first 6 belt layers were completed using a spiral winding method, rather than using a 1 / 4 turn increment per layer (see Table 1). This is related to the tire's excessive static imbalance (56N·cm > 52N·cm), which was subsequently repaired and met the standards.

[0068] Example 1, an aircraft tire, was designed according to the structural parameters of the radial aircraft tire belt layer structure discussed above. The belt layer width satisfies the relationship W1 > W2 > W3. The materials for the main and auxiliary belt layers were selected according to the scope of the invention patent. The first and third belt layers were made of 1500D1×4 aramid with a breaking strength ≥1400N and an elongation at break of 3.5±1.5%. The second belt layer was made of 2800dtex / 3N66 with a breaking strength ≥690N and an elongation at break of 26±3.0%. The requirements of s*n+1 / 4n for the first and third belt layers were met. The tire of this invention example has an outer tire expansion rate close to zero, a relatively good static imbalance index, and the best durability index of the tread area. Examples 2 and 3, using similar design parameters, yielded almost the same conclusions.

[0069] For the tire of Comparative Example 2, the tire crown separation durability is slightly improved. The main difference from Comparative Example 1 is that the main belt layer is made of aramid material, which increases the strength. The second belt layer is reduced to 2 layers. However, the winding increment method is not used during the spiral winding process. The tire of this comparative example has a very small expansion rate, but the single static imbalance exceeds the standard and the durability is not high. This further verifies that the design indicators of Invention Example 1 have a close correlation with the tire crown durability performance of the product.

[0070] For the tires of Comparative Examples 3 and 4, the tire crown separation durability is slightly improved. The main difference from Comparative Example 1 is that the first belt layer, the second belt layer, and the third belt layer are all made of nylon material, and the spiral winding process adopts the winding increment method. The tire of this comparative example has a larger expansion rate and normal static imbalance. However, due to the change in the material of the first belt layer and the third belt layer, the inflation expansion rate of the aircraft tire is increased. The carcass ply and belt layer reshape the stress system during inflation, and the stress change rate of the skeleton material is large, which affects the durability performance index of the aircraft tire.

[0071]

[0072]

[0073] Table 1

[0074] In summary, the embodiments of the present invention provide a radial aircraft tire crown belt layer structure and a radial aircraft tire. By setting the circumference of the first belt strip to s*n+(1 / 6-1 / 2)n, that is, the first layer of the layered structure is wound from point O to point D in the second direction (axial direction) and then wound for more than n / 4 to reach point F. Then the second layer of the layered structure is wound from point F in the opposite direction to the second direction (axial direction) to point G. Then the third layer of the layered structure is wound from point G to point H in the axial direction. The fourth layer of the layered structure is wound from point H to point O. The first belt layer configured in this way can make the width of the first belt layer more uniform at each position of the tire carcass layer, and make the first belt layer more stable in terms of stress and other aspects.

[0075] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A crown belt structure for radial aircraft tires, characterized in that, include: Strengthen the ply, carcass, and crown areas; The reinforcing ply layer is disposed between the carcass layer and the crown region; The reinforcing ply includes: a first belt layer, a second belt layer, and a third belt layer; the first belt layer is disposed on the carcass layer, the third belt layer is disposed on the first belt layer, and the second belt layer is disposed on the third belt layer; Both the first belt layer and the third belt layer are composed of multiple layers of layered structures stacked radially; the winding directions of two adjacent layered structures in the first belt layer and the third belt layer are opposite in the axial direction; the layered structure is formed by spirally winding a first belt strip around the tire carcass layer at least s turns; the circumference of each turn of the first belt strip around the tire carcass layer is n; the circumference of the first belt strip used for winding the layered structure is s*n+(1 / 6-1 / 2)n, and the circumference of the first belt strip used for winding each layer of the layered structure in the first belt layer and the third belt layer is equal. In this configuration, the first layer and the third layer are each of two adjacent layered structures, with the layer closer to the carcass being the first layer and the layer further away from the carcass being the second layer; the second layer begins to be wound axially in the opposite direction from the end of the first layer where the first belt strip ends; The width of the first belt strip is b; the angle between the first belt strip and the circumferential direction is α; the first belt strip has a first side and a second side that are parallel to each other; for every half turn of the first belt strip around the tire carcass, the first belt strip is offset by b / 2cosα along the first direction; for every full turn of the first belt strip around the tire carcass, the first belt strip is offset by b / cosα along the first direction; the first direction is parallel to the axial direction.

2. The radial aircraft tire crown belt layer structure according to claim 1, characterized in that, The first belt layer, the third belt layer, and the second belt layer are all composed of a first belt strip spiral; the width of the first belt layer is greater than the width of the third belt layer, and the width of the second belt layer is greater than the width of the third belt layer but less than the width of the first belt layer.

3. The radial aircraft tire crown belt layer structure according to claim 1, characterized in that, The perimeter of the first belt strip used for winding each layer of the layered structure is s*n+1 / 4n.

4. The radial aircraft tire crown belt layer structure according to claim 1, characterized in that, The first belt strip is formed by extruding and coating multiple fiber skeletons; the multiple fiber skeletons are arranged at equal intervals and are parallel to each other.

5. The radial aircraft tire crown belt layer structure according to claim 4, characterized in that, The area of ​​adhesive coating in the cross-section of the first belt strip is S_adhesive, and the area of ​​the fiber skeleton in the cross-section of the first belt strip is S_line; S_adhesive: S_line = 1.0-1.5 times.

6. The radial aircraft tire crown belt layer structure according to claim 5, characterized in that, The fiber skeleton of the first and third belt layers is made of 1500D1×4 aramid with a breaking strength ≥1400N and a breaking elongation of 3.5±1.5%; the fiber skeleton of the second belt layer is made of 2800dtex / 3 N66 with a breaking strength ≥690N and a breaking elongation of 26±3.0%.

7. The radial aircraft tire crown belt layer structure according to claim 1, characterized in that, The first belt layer has 4-6 layers; the second belt layer has 4-6 layers; and the third belt layer has 2-4 layers.

8. The radial aircraft tire crown belt layer structure according to claim 1, characterized in that, The second belt layer is wound in a "Z" shape around the third belt layer.

9. A radial aircraft tire, characterized in that, include: The radial aircraft tire crown belt structure as described in any one of claims 1-8.

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