High-deformation-resistant lightweight radial aircraft tire belted layer structure and winding method thereof

Abstract

The invention belongs to the technical field of meridian aircraft tire manufacturing, and particularly relates to a high-deformation-resistant light-weight meridian aircraft tire belt ply structure and a winding method thereof.The belt ply structure is provided with six layers, every two layers of belt plies are wound into a group, the belt plies adopt high-strength cord fabric strips with the width ranging from 10 mm to 12 mm, and the width of the high-strength cord fabric strips ranges from 10 mm to 12 mm. The cord fabric strips of the first to fourth belted layers are wound at a large angle with the included angle of 10-15 degrees with the circumferential direction of the tire, the cord fabric strips of the fifth to sixth belted layers are flatly wound at the included angle of 0 degree with the circumferential direction of the tire, and the widths of each group of belted layers are different and have a specific difference level. The meridian aircraft tire has the characteristics of small deformation and light weight under the condition of meeting harsh use conditions of an aircraft, the overall advantages of the meridian aircraft tire in the aspects of high speed resistance, high deformation resistance and light weight are solved, and the use requirements of the aircraft are met through a dynamic simulation test according to actual working conditions.

Description

Technical Field

[0001] The invention belongs to the technical field of radial aircraft tire manufacturing, in particular to a high-deformation-resistant lightweight radial aircraft tire belt structure and a winding method thereof. Background Art

[0002] Aircraft tires are very important landing and take-off parts of aircraft, with the characteristics of high speed, high load, large deformation, high internal pressure, etc. Aircraft tires are divided into bias aircraft tires and radial aircraft tires. Among them, compared with bias aircraft tires, the performance of radial aircraft tires is more outstanding. The weight of radial tires is much lighter than that of bias tires of the same specifications (about 20% lighter), meeting the use requirements of high speed resistance, high deformation resistance, and lightweight, and increasing the aircraft's payload capacity. In addition, because the structure of radial aircraft tires is easier to withstand the stress of tires during takeoff and landing of aircraft, the tread performance of radial aircraft tires is significantly improved compared to bias tires. In addition, high temperature can cause the performance of tires to decline rapidly or even damage them, while radial aircraft tires generate less heat during driving, which is conducive to maintaining tire performance and improving the ability to overload over long distances.

[0003] The inner structure of radial aircraft tires consists of carcass, belt layer and wire ring. The belt layer is made of high-strength fiber material, and the belt layer tightly ties the carcass to keep the circumferential length of the tire basically unchanged or with very little change. The sidewall is the main part that bears flexural deformation. The sidewall is flexible, the crown and bead are rigid, and the shoulder is the transition area between the rigid crown and the flexible sidewall.

[0004] Radial aircraft tires are used under high speed and high load conditions, with a rated internal pressure of 1050KPa, a maximum speed of 385km / h, a rated load of 115KN, and a weight of ≤51kg. Under more demanding operating conditions, tires are subjected to high-frequency high stress and large strain, especially the large centrifugal force and shear force between the belt cord layers and at the edges of the belt layers, which can easily cause tread shedding and belt edge delamination and bulging failures, seriously affecting flight safety.

[0005] When the discontinuous ends of traditional cross-belt layers are fixed at both ends in the width direction of the tire, shear deformation stress concentration occurs. At the same time, the traditional multi-layer belt layer laying causes poor adhesion between the belt layer and the tire body, which further aggravates the shear deformation and stress concentration at the free ends of the belt layer. Summary of the invention

[0006] In order to solve the above problems existing in the existing radial aircraft tire belt layer, the object of the present invention is to provide a high-deformation resistant lightweight radial aircraft tire belt layer structure and a winding method thereof.

[0007] The objective of the present invention is achieved through the following technical solutions: The belt layer structure of the present invention has six belt layers in total, and every two layers are wound into a group. The belt layers are, from the inside to the outside, the first belt layer, the second belt layer, the third belt layer, the fourth belt layer, the fifth belt layer and the sixth belt layer, and each belt layer is a cord strip; the first belt layer to the fourth belt layer are wound on the radial aircraft tire in an S-shaped manner, that is, the cord strips of the first belt layer to the fourth belt layer have an angle with the circumference of the radial aircraft tire, and the fifth belt layer and the sixth belt layer are wound on the radial aircraft tire in a flat winding manner, that is, the circumferential angle between the fifth belt layer and the sixth belt layer and the radial aircraft tire is 0°; the width of each belt layer decreases layer by layer from the first belt layer to the sixth belt layer.

[0008] Wherein: the circumferential angle between the cord strips of the first belt layer to the fourth belt layer and the radial aircraft tire is 10° to 15°.

[0009] The circumferential angle between the cord strips of the first to fourth belt layers and the radial aircraft tire is preferably 10.8° to 11.5°.

[0010] The circumferential angles between the cord strips of the first to fourth belt layers and the radial aircraft tire decrease layer by layer.

[0011] The widths of the first belt layer to the sixth belt layer decrease layer by layer in an arithmetic progression.

[0012] The widths of the first and second belt layers of the first group are 305 mm to 310 mm, the widths of the third and fourth belt layers of the second group are 295 mm to 300 mm, and the widths of the fifth and sixth belt layers of the third group are 285 mm to 290 mm.

[0013] Shoulder pads are provided at the edge portions of both ends of the belt layers of each layer. The width of the shoulder pads is 25 mm to 35 mm, the thickness is 5 mm to 10 mm, the tensile strength of the shoulder pads is ≥18.5 MPa, the elongation at break is ≥350%, the 100% tensile stress is ≥14.5 MPa, the 300% tensile stress is ≥14.5 MPa, the tensile permanent deformation is ≤25%, the hardness is Shore A 74±2 degrees, the plasticity value is ≤520 mm / 100, and the specific gravity is 1.155±0.01 g / cm 3 .

[0014] The width of the cord strip is 10mm~15mm, the breaking strength of the cord on the cord strip is ≥670N / root, the elongation at a fixed load of 100N is 6.0%±0.6%, the elongation at break is 21.0%±2.0%, the bonding strength is ≥210N / cm, the initial twist is 20.5±1.5T / 10cm, and the secondary twist is 20.5±1.5T / 10cm.

[0015] The winding method of the high deformation resistant lightweight radial aircraft tire belt structure of the present invention is: The first to fourth belt layers are wound on the radial aircraft tire in an S-shaped manner, and the fifth and sixth belt layers are wound on the radial aircraft tire in a flat-wound manner.

[0016] Wherein: the first to sixth belt layers are wound sequentially from the inside to the outside, or two belt layers of each group are wound simultaneously.

[0017] The advantages and positive effects of the present invention are: 1. The belt layer structure of the present invention is provided with six high-strength belt layers. Compared with the prior art, it can reduce the overall number of belt layers while meeting good performance requirements, thereby achieving the purpose of lightweight radial aircraft tires.

[0018] 2. The first four belt layers of the present invention have a large angle with the tire circumference, and the angle between the last two belt layers and the tire circumference is 0°, thereby well controlling the outer edge expansion size of the pneumatic tire and achieving the purpose of low deformation.

[0019] 3. The widths of the various belt layers of the present invention are different, which disperses the stress at the ends of the belt layers.

[0020] 4. The belt layer structure of the present invention has great advantages in reducing the weight of radial aircraft tires. A tire with fewer belt layers can still pass the burst test normally, which reduces weight and reduces tire heat generation.

[0021] 5. The belt layer of the present invention adopts a winding method combining large-angle S-shaped winding and flat winding, so that the stress at the end points of the belt layer is reduced or eliminated. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the internal structure of the radial aviation tire of the present invention; Figure 2 for Figure 1 A local enlarged view of the middle belt layer; Figure 3 This is a structural principle diagram of the S-shaped winding of the belt layer of the present invention; Figure 4 This is a structural principle diagram of the flat winding of the belt layer of the present invention; Among them: 1 is the carcass, 2 is the crown, 3 is the belt layer, 4 is the shoulder, 5 is the sidewall, 6 is the first belt layer, 7 is the second belt layer, 8 is the third belt layer, 9 is the fourth belt layer, 10 is the fifth belt layer, 11 is the sixth belt layer, and 12 is the shoulder pad. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings.

[0024] like Figure 1 , Figure 2 As shown, the belt layer 3 of the present invention has six layers, and every two layers are wound into a group. The belt layers 3 are sequentially composed of a first belt layer 6, a second belt layer 7, a third belt layer 8, a fourth belt layer 9, a fifth belt layer 10 and a sixth belt layer 11 from the inside to the outside, and each belt layer 3 is a cord strip; the first belt layer 6 to the fourth belt layer 9 are wound on the radial aircraft tire in an S-shaped manner, that is, the cord strips of the first belt layer 6 to the fourth belt layer 9 have an angle with the circumferential direction of the radial aircraft tire (such as Figure 3 As shown in FIG. 1 ), the fifth belt layer 10 and the sixth belt layer 11 are wound on the radial aircraft tire in a flat winding manner, that is, the circumferential angle between the fifth belt layer 10 and the sixth belt layer 11 and the radial aircraft tire is 0° (as shown in FIG. Figure 4 As shown); in order to disperse the stress at the end of the belt layer 3, the width of each belt layer 3 is different, and the width of each belt layer 3 decreases layer by layer from the first belt layer 6 to the sixth belt layer 11.

[0025] In this embodiment, each belt layer 3 adopts 1880dtex / 2 / 2-74E nylon cord, the width of the cord strip is 10mm~15mm, the cord breaking strength on the cord strip is ≥670N / root, the elongation at 100N fixed load is 6.0%±0.6%, the elongation at break is 21.0%±2.0%, the bonding strength is ≥210N / cm, the primary twist is 20.5±1.5T / 10cm, and the secondary twist is 20.5±1.5T / 10cm.

[0026] In this embodiment, the circumferential angle between the cord strips of the first belt layer 6 to the fourth belt layer 9 and the radial aircraft tire is 10° to 15°. In order to meet the requirements of the inflated outer edge size of the radial aircraft tire and the high speed requirement of 385km / h, the circumferential angle between the cord strips of the first belt layer 6 to the fourth belt layer 9 and the radial aircraft tire is preferably 10.8° to 11.5°, and the circumferential angle between the cord strips of the first belt layer 6 to the fourth belt layer 9 and the radial aircraft tire decreases layer by layer.

[0027] In this embodiment, the width of the first belt layer 6 and the second belt layer 7 of the first group is 305mm~310mm, the width of the third belt layer 8 and the fourth belt layer 9 of the second group is 295mm~300mm, and the width of the fifth belt layer 10 and the sixth belt layer 11 of the third group is 285mm~290mm; the widths of the first belt layer 6 to the sixth belt layer 11 decrease layer by layer in an arithmetic progression, specifically, the width of the first belt layer 6 is 310mm, the width of the second belt layer 7 is 305mm, the width of the third belt layer 8 is 300mm, the width of the fourth belt layer 9 is 295mm, the width of the fifth belt layer 10 is 290mm, and the width of the sixth belt layer 11 is 285mm.

[0028] In this embodiment, shoulder pads 12 are provided at the edge portions of both ends of each belt layer 3. The width of the shoulder pads 12 is 25 mm to 35 mm, the thickness is 5 mm to 10 mm, the tensile strength of the shoulder pads 12 is ≥18.5 MPa, the elongation at break is ≥350%, the 100% tensile stress is ≥14.5 MPa, the 300% tensile stress is ≥14.5 MPa, the tensile permanent deformation is ≤25%, the hardness is Shore A 74±2 degrees, the plasticity value is ≤520 mm / 100, and the specific gravity is 1.155±0.01 g / cm 3 .

[0029] The winding method of the high deformation resistant lightweight radial aircraft tire belt layer structure of the present invention winds the first belt layer 6 to the fourth belt layer 9 on the radial aircraft tire in an S-shaped manner, and winds the fifth belt layer 10 and the sixth belt layer 11 on the radial aircraft tire in a flat winding manner.

[0030] The main features of radial aircraft tires are simple structure and high process precision; the angle between the arrangement direction of the carcass 1 cord and the tire meridian section is 0°; the cords of the belt layer 3 are arranged in the meridian direction, and the carcass circumferential strength is small with fewer layers, so the belt layer 3 is used to tighten the carcass 1 to ensure the rigidity of the tire in the circumferential direction. The belt layer 3 is a buffer layer between the crown 2 and the carcass 1 cords, which plays a role in buffering and maintaining the rigidity of the tire in the circumferential direction, so that the tire has good load-bearing capacity and high-speed resistance; the rubber materials in different parts make the overall performance of the tire extremely exerted. The sidewall 5 is the main part that bears flexural deformation. The sidewall 5 is flexible, the crown 2 and the carcass 1 are rigid, and the shoulder 4 is the transition area between the rigid crown 2 and the flexible sidewall 5.

[0031] The belt layer winding is to wind a bunch of continuous rubber cord strips clockwise or counterclockwise along the circumference of the tire at a set winding angle; when the cord strips are wound around the left and right edges of the belt layer, they are wound in a wave-like or folded direction; when winding the next layer, the cord strips are arranged in parallel with the cord strips wound on the previous layer, and when encountering the cord strips folded back on the previous layer, they cross the folded back cord strips on the previous layer until the edge of the belt layer and then fold back. In this way, the first belt layer 6 to the sixth belt layer 11 are wound from the inside to the outside.

[0032] Alternatively, two bundles of cord strips are provided, and the two belt layers 3 of each group can be wound simultaneously.

[0033] The radial aircraft tire of the present invention can avoid the problems of tread shedding, tire blowout, tire bead blistering, tire bead cracking, etc.

Claims

1. A high-deformation-resistant lightweight radial aircraft tire belt structure, characterized by: The belt layer (3) has six layers in total, and each two layers are wound into a group. The belt layers (3) are, from the inside to the outside, a first belt layer (6), a second belt layer (7), a third belt layer (8), a fourth belt layer (9), a fifth belt layer (10), and a sixth belt layer (11). Each belt layer (3) is a cord strip. The first belt layer (6) to the fourth belt layer (9) are wound on the radial aircraft tire in an S-shaped manner, that is, the first belt layer The cord strips of the belt layers (6) to the fourth belt layer (9) have an angle with the circumference of the radial aircraft tire. The fifth belt layer (10) and the sixth belt layer (11) are wound on the radial aircraft tire in a flat winding manner, that is, the circumferential angle between the fifth belt layer (10) and the sixth belt layer (11) and the radial aircraft tire is 0°; the width of each belt layer (3) decreases layer by layer from the first belt layer (6) to the sixth belt layer (11).

2. The high deformation resistant lightweight radial aircraft tire belt structure according to claim 1, characterized in that: The circumferential angle between the cord strips of the first belt layer (6) to the fourth belt layer (9) and the radial aircraft tire is 10° to 15°.

3. The high deformation resistant lightweight radial aircraft tire belt structure according to claim 2, characterized in that: The circumferential angle between the cord strips of the first belt layer (6) to the fourth belt layer (9) and the radial aircraft tire is preferably 10.8° to 11.5°.

4. The high deformation resistant lightweight radial aircraft tire belt structure according to claim 1, characterized in that: The circumferential angle between the cord strips of the first belt layer (6) to the fourth belt layer (9) and the radial aircraft tire decreases layer by layer.

5. The high deformation resistant lightweight radial aircraft tire belt structure according to claim 1, characterized in that: The widths of the first belt layer (6) to the sixth belt layer (11) decrease layer by layer in an arithmetic progression.

6. The high deformation resistant lightweight radial aircraft tire belt structure according to claim 1, characterized in that: The width of the first belt layer (6) and the second belt layer (7) of the first group is 305 mm to 310 mm, the width of the third belt layer (8) and the fourth belt layer (9) of the second group is 295 mm to 300 mm, and the width of the fifth belt layer (10) and the sixth belt layer (11) of the third group is 285 mm to 290 mm.

7. The high deformation resistant lightweight radial aircraft tire belt structure according to claim 1, characterized in that: A shoulder pad (12) is provided at the edge of both ends of each layer of the belt layer (3). The shoulder pad (12) has a width of 25 mm to 35 mm and a thickness of 5 mm to 10 mm. The shoulder pad (12) has a tensile strength of ≥18.5 MPa, an elongation at break of ≥350%, a 100% tensile stress of ≥14.5 MPa, a 300% tensile stress of ≥14.5 MPa, a tensile permanent deformation of ≤25%, a Shore A hardness of 74±2 degrees, a plasticity value of ≤520 mm / 100, and a specific gravity of 1.155±0.01 g / cm 3 .

8. The high deformation resistant lightweight radial aircraft tire belt structure according to claim 1, characterized in that: The width of the cord strip is 10mm~15mm, the breaking strength of the cord on the cord strip is ≥670N / root, the elongation at a fixed load of 100N is 6.0%±0.6%, the elongation at break is 21.0%±2.0%, the bonding strength is ≥210N / cm, the initial twist is 20.5±1.5T / 10cm, and the secondary twist is 20.5±1.5T / 10cm.

9. A method for winding a high deformation resistant lightweight radial aircraft tire belt structure according to any one of claims 1 to 8, characterized in that: The first belt layer (6) to the fourth belt layer (9) are wound on the radial aircraft tire in an S-shaped manner, and the fifth belt layer (10) and the sixth belt layer (11) are wound on the radial aircraft tire in a flat winding manner.

10. The winding method according to claim 9, characterized in that: The first belt layer (6) to the sixth belt layer (11) are wound sequentially from the inside to the outside, or the two belt layers (3) of each group are wound simultaneously.

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