Meridian aircraft tire bead structure for large deflection

Abstract

The invention relates to the technical field of meridian aircraft tires, in particular to a meridian aircraft tire bead structure aiming at large sinkage, which comprises a circular-section steel ring, triangular-section filling rubber, a tire body cord fabric layer and a tire body material layer, and the triangular-section filling rubber is further divided into an inner-layer filling rubber part and an outer-layer filling rubber part which are connected with each other. A boundary section between the inner-layer filling adhesive part of the triangular-section filling adhesive and the outer-layer filling adhesive part of the triangular-section filling adhesive in the section is a line segment L, and the line segment L is tangent to the outermost peripheral point, located in the horizontal direction, of the circular section of the circular-section steel ring. According to the invention, the problem that the tire bead position of the large-sinkage meridian aircraft tire is easy to delaminate and swell can be solved, the use requirements of the meridian aircraft tire can be met, the tire bead structure is optimized, the performance and reliability of the aircraft tire are improved, the maintenance cost and use risk of the tire are reduced, and a powerful guarantee is provided for aviation safety.

Description

Technical Field

[0001] The invention relates to the technical field of radial aircraft tires, in particular to a radial aircraft tire bead structure for large sinking amount. Background Art

[0002] Aircraft tires are important parts of aircraft, because they need to meet the requirements of high internal pressure, high load, high speed and deformation under great impact load. Due to its own structural characteristics, when radial aircraft tires carry large loads, the sidewalls will deform and sink by about 30%, and the bead area will undergo passive deformation due to the large amount of sinking. When the sinking reaches 32%, the rubber in the bead area will generate heat due to the viscoelastic effect of the material itself, and the temperature will rise. The bead will repeat this process during the rotation of the tire, and the accumulated heat will cause the temperature of the bead area to be extremely high. High temperature accompanied by repeated flexion deformation greatly reduces the life of the bead material, and it is easy to cause a gap between the carcass cord layer and the adjacent bead material at the interface, and then delamination and bulging will affect the carcass strength and cause explosion.

[0003] Therefore, in order to meet the harsh operating conditions, improving the durability of the tire bead is an important research direction for aviation tires. Summary of the invention

[0004] In view of the above problems, an object of the present invention is to provide a radial aircraft tire bead structure for large sinkage.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] A bead structure for a radial aircraft tire with a large amount of subsidence, comprising a round-section steel ring, a triangular-section filling rubber, a carcass cord layer, and a carcass material layer, wherein the carcass cord layer is coated on the outer side of a whole formed by the round-section steel ring and the triangular-section filling rubber, and the carcass material layer is divided into a bead protection rubber layer and a supporting rubber layer connected to each other, wherein the bead protection rubber layer and the supporting rubber layer are respectively located on the outer side of the carcass cord layer, the bead protection rubber layer is used to connect with the rim of the corresponding radial aircraft tire, and the supporting rubber layer is located on one side of an adjacent wheel flange of the carcass cord layer close to the rim of the corresponding radial aircraft tire;

[0007] The triangular cross-section filling glue is divided into an inner filling glue part and an outer filling glue part that are connected to each other. The dividing line segment in the cross section between the inner filling glue part of the triangular cross-section filling glue and the outer filling glue part of the triangular cross-section filling glue is line segment L. The line segment L is tangent to the outermost point of the circular cross-section of the circular cross-section steel ring in the horizontal direction.

[0008] The highest point of the inner filling glue part of the triangle cross-section filling glue in the vertical direction is point A, and point A is located on the line segment L;

[0009] The outermost end point of an adjacent wheel rim of the corresponding radial aircraft tire is point X, the boundary point between the wheel rim and the wheel rim itself is point O, the X point is projected around point O and takes the line segment connecting point X and point O as the radius to make an arc S, and the height position of point A is not higher than the height position of the intersection of the projection arc S and the straight line where the line segment L is located.

[0010] The intersection of a straight line parallel to the horizontal plane passing through point A and the outer side surface of the carcass material layer is point C, and the horizontal distance between point C and point A is 1-1.5 times the radius of the circular cross-section of the circular cross-section steel ring.

[0011] The intersection of the side surface of the supporting rubber layer close to the carcass cord layer and the projection arc S is point B, and the thickness of the upper part of an adjacent wheel flange of the rim of the corresponding radial aviation tire measured through point B is 0.5-1 times the radius of the circular cross-section of the circular cross-section steel ring.

[0012] The thickness of the carcass material layer at an upper portion of an adjacent wheel flange of the rim of the corresponding radial aircraft tire measured through point B is equal to the length of the line segment connecting point B and point C.

[0013] The bead protection rubber layer has an extending portion extending to the outer side of the supporting rubber layer.

[0014] The height position of the lowest point of the inner layer filling rubber part of the triangular cross-section filling rubber in the vertical direction is not lower than the height position of the outermost point of the circular cross-section of the circular cross-section steel ring in the horizontal direction.

[0015] Adhesive is provided between the triangular cross-section filling glue as a whole and the circular cross-section steel ring.

[0016] The elastic modulus of the inner filling rubber part of the triangular cross-section filling rubber, the elastic modulus of the outer filling rubber part of the triangular cross-section filling rubber, the elastic modulus of the carcass cord layer and the elastic modulus of the supporting rubber layer decrease in sequence;

[0017] The Shore A hardness of the inner filling rubber part of the triangular cross-section filling rubber, the Shore A hardness of the outer filling rubber part of the triangular cross-section filling rubber, the Shore A hardness of the carcass cord layer and the Shore A hardness of the supporting rubber layer decreases in sequence.

[0018] The Shore A hardness of the inner layer filling glue part of the triangular cross-section filling glue is 75-85 degrees, and the Shore A hardness of the outer layer filling glue part of the triangular cross-section filling glue is 69-75 degrees.

[0019] The advantages and positive effects of the present invention are:

[0020] The bead structure for radial aircraft tires with large subsidence proposed in the present invention can solve the problem of delamination and bulging easily occurring at the bead position of radial aircraft tires with large subsidence, meet the use requirements of radial aircraft tires, optimize the bead structure, improve the performance and reliability of aircraft tires, reduce the maintenance cost and use risk of tires, and provide strong protection for aviation safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of a partial cross-section structure of a radial aircraft tire corresponding to the present invention.

[0022] In the figure: 1 is a steel ring with a circular cross section, 2 is a filling rubber with a triangular cross section, 201 is an inner filling rubber part, 202 is an outer filling rubber part, 3 is a carcass cord layer, 4 is a carcass material layer, 401 is a tire bead protective rubber layer, and 402 is a supporting rubber layer;

[0023] 001 is the rim and 0011 is the flange. DETAILED DESCRIPTION

[0024] The following is combined with Figure 1 The present invention is further described in detail.

[0025] A radial aircraft tire bead structure for large sinkage, such as Figure 1 As shown, in this embodiment, a round-section steel ring 1, a triangular-section filling rubber 2, a carcass ply 3, and a carcass material layer 4 are included. The carcass ply 3 is coated on the outer side of the whole formed by the round-section steel ring 1 and the triangular-section filling rubber 2. The carcass material layer 4 is divided into a bead protection rubber layer 401 and a support rubber layer 402 connected to each other. The bead protection rubber layer 401 and the support rubber layer 402 are respectively located on the outer side of the carcass ply 3. The bead protection rubber layer 401 is used to connect with the rim 001 of the corresponding radial aircraft tire. The support rubber layer 402 is located on the side of a wheel flange 0011 of the carcass ply 3 close to the rim 001 of the corresponding radial aircraft tire. The basic arrangement between the round-section steel ring 1, the triangular-section filling rubber 2, the carcass ply 3, the carcass material layer 4, and the rim 001 in this embodiment is the prior art.

[0026] In the radial aircraft tire bead structure for large sinking amount proposed by the present invention, the triangular cross-section filling rubber 2 is divided into an inner layer filling rubber part 201 and an outer layer filling rubber part 202 connected to each other, and the dividing line segment between the inner layer filling rubber part 201 of the triangular cross-section filling rubber 2 and the outer layer filling rubber part 202 of the triangular cross-section filling rubber 2 in the cross section is a line segment L, and the line segment L and the outermost point of the circular cross section of the circular cross section steel ring 1 in the horizontal direction ( Figure 1The line segment L is tangent to the horizontal plane at point E in the figure.

[0027] Specifically, in this embodiment, the highest point of the inner filling glue part 201 of the triangular cross-section filling glue 2 in the vertical direction is point A, and point A is located on the line segment L.

[0028] The outermost end point of an adjacent rim 0011 of the rim 001 of the corresponding radial aircraft tire is point X, the boundary point between the rim 0011 of the rim 001 and the rim 001 itself is point O, and point X is projected around point O with the line segment connecting point X and point O as the radius to make an arc S.

[0029] In this embodiment, the height position of point A is not higher than the height position of the intersection of the projection arc S and the straight line where the line segment L is located. In this embodiment, the height position of the lowest point of the inner layer filling rubber part 201 of the triangular cross-section filling rubber 2 in the vertical direction is not lower than the height position of the outermost point (point E) of the circular cross-section of the circular cross-section steel ring 1 in the horizontal direction.

[0030] In this embodiment, the intersection of a straight line parallel to the horizontal plane passing through point A and the outer side surface of the carcass material layer 4 is point C. The horizontal distance d1 between point C and point A is 1-1.5 times the radius R of the circular cross-section of the circular cross-section steel ring 1.

[0031] The intersection of the side surface of the supporting rubber layer 402 close to the carcass cord layer 3 and the projection arc S is point B, and the thickness d2 of the upper portion of the carcass material layer 4 located at an adjacent rim 0011 of the rim 001 of the corresponding radial aircraft tire measured through point B is 0.5-1 times the radius R of the circular cross-section of the circular cross-section steel ring 1. In this embodiment, the thickness d2 of the upper portion of the carcass material layer 4 located at an adjacent rim 0011 of the rim 001 of the corresponding radial aircraft tire measured through point B is just equal to the length of the line segment connecting point B and point C, which is convenient for design and testing; for different tires, the length of the line segment connecting point B and point C may not be equal to the above thickness d2. In this embodiment, the bead protection rubber layer 401 has an extension portion extending to the outside of the supporting rubber layer 402, so the thickness d2 includes the thickness of the portion of the supporting rubber layer 402 passing through point B and the corresponding thickness of the extension portion extending to the outside of the supporting rubber layer 402. For different tires, the bead protection rubber layer 401 may not have an extension portion extending to the outside of the supporting rubber layer 402, that is, in this case, the thickness d2 only includes the thickness of the portion of the supporting rubber layer 402 passing through point B.

[0032] Specifically, in this embodiment, an adhesive is provided between the entire triangular cross-section filling glue 2 and the circular cross-section steel ring 1 to strengthen the connection between the entire triangular cross-section filling glue 2 and the circular cross-section steel ring 1. The formula of the adhesive in this embodiment can adopt the existing technology, so that one end of the adhesive molecule is a polar group that exists in affinity with the circular cross-section steel ring 1 through physical adsorption, and the other end is a non-polar group that exists in affinity with the rubber in the form of a covalent bond, and the elastic modulus of the adhesive is between that of the circular cross-section steel ring 1 and the triangular cross-section filling glue 2 to reduce stress concentration when subjected to force.

[0033] Specifically, in this embodiment, the elastic modulus of the inner filling rubber part 201 of the triangular cross-section filling rubber 2, the elastic modulus of the outer filling rubber part 202 of the triangular cross-section filling rubber 2, the elastic modulus of the carcass cord layer 3, and the elastic modulus of the supporting rubber layer 402 decrease in sequence; the Shore A hardness of the inner filling rubber part 201 of the triangular cross-section filling rubber 2, the Shore A hardness of the outer filling rubber part 202 of the triangular cross-section filling rubber 2, the Shore A hardness of the carcass cord layer 3, and the Shore A hardness of the supporting rubber layer 402 decrease in sequence. The Shore A hardness of the inner filling rubber part 201 of the triangular cross-section filling rubber 2 is 75-85 degrees, and the Shore A hardness of the outer filling rubber part 202 of the triangular cross-section filling rubber 2 is 69-75 degrees.

[0034] In a specific comparative experimental example, when the tire with the triangular cross-section filling rubber 2 as a whole was subjected to the CTSO-C62e condition dynamic test, the tire completed a total of 61 dynamic simulation tests, including 47 normal takeoff tests, 3 long-distance takeoff tests, 8 normal taxiing tests, 2 overload taxiing tests, and 1 overload takeoff test. After the 31st normal takeoff test, the tire bead was cracked due to delamination and bulging. However, the tire bead was intact after the same test using the triangular cross-section filling rubber 2 proposed by the present invention, which was divided into an inner layer filling rubber part 201 and an outer layer filling rubber part 202. It can be seen from the experiment that the bead structure of the radial aircraft tire for large subsidence proposed by the present invention can solve the problem of delamination and bulging at the bead position of the radial aircraft tire with large subsidence, and can meet the use requirements of the radial aircraft tire.

Claims

1. A bead structure for a radial aircraft tire with a large amount of subsidence, comprising a round-section steel ring (1), a triangular-section filling rubber (2), a carcass cord layer (3), and a carcass material layer (4), wherein the carcass cord layer (3) is coated on the outer side of a whole formed by the round-section steel ring (1) and the triangular-section filling rubber (2), and the carcass material layer (4) is divided into a bead protection rubber layer (401) and a supporting rubber layer (402) connected to each other, wherein the bead protection rubber layer (401) and the supporting rubber layer (402) are respectively located on the outer side of the carcass cord layer (3), the bead protection rubber layer (401) is used to connect with a rim (001) of a corresponding radial aircraft tire, and the supporting rubber layer (402) is located on a side of the carcass cord layer (3) close to an adjacent wheel flange (0011) of the rim (001) of the corresponding radial aircraft tire; The bead structure of a radial aircraft tire for large sinking is characterized in that: the triangular cross-section filling rubber (2) is divided into an inner layer filling rubber part (201) and an outer layer filling rubber part (202) connected to each other, and the dividing line segment between the inner layer filling rubber part (201) of the triangular cross-section filling rubber (2) and the outer layer filling rubber part (202) of the triangular cross-section filling rubber (2) in the cross section is a line segment L, and the line segment L is tangent to the outermost point of the circular cross section of the circular cross-section steel ring (1) in the horizontal direction.

2. The radial aircraft tire bead structure for large sinking according to claim 1, characterized in that: The highest point of the inner filling glue part (201) of the triangle-shaped filling glue (2) in the vertical direction is point A, and point A is located on the line segment L; The outermost end point of an adjacent wheel flange (0011) of the rim (001) of the corresponding radial aircraft tire is point X, the boundary point between the wheel flange (0011) of the rim (001) and the rim (001) itself is point O, the X point is used to make a projection arc S around the O point and with the line segment connecting the X point and the O point as the radius, and the height position of the A point is not higher than the height position of the intersection of the projection arc S and the straight line where the line segment L is located.

3. The radial aircraft tire bead structure for large sinking according to claim 2, characterized in that: The intersection of a straight line parallel to the horizontal plane passing through point A and the outer side surface of the carcass material layer (4) is point C, and the horizontal distance between point C and point A is 1-1.5 times the radius of the circular section of the circular section steel ring (1).

4. The radial aircraft tire bead structure for large sinking according to claim 3, characterized in that: The intersection of the side surface of the supporting rubber layer (402) close to the carcass cord layer (3) and the projection arc S is point B, and the thickness of the upper part of an adjacent wheel flange (0011) of the rim (001) of the corresponding radial aircraft tire measured through point B is 0.5-1 times the radius of the circular cross-section of the circular cross-section steel ring (1).

5. A radial aircraft tire bead structure for large sinking according to claim 4, characterized in that: The thickness of the upper portion of the carcass material layer (4) located at an adjacent wheel flange (0011) of the rim (001) of the corresponding radial aircraft tire measured through the point B is equal to the length of the line segment connecting the point B and the point C.

6. The radial aircraft tire bead structure for large sinking according to claim 1, characterized in that: The tire bead protection rubber layer (401) has an extension portion extending to the outside of the supporting rubber layer (402).

7. The radial aircraft tire bead structure for large sinking according to claim 1, characterized in that: The height position of the lowest point of the inner filling rubber part (201) of the triangular cross-section filling rubber (2) in the vertical direction is not lower than the height position of the outermost point of the circular cross-section of the circular cross-section steel ring (1) in the horizontal direction.

8. The radial aircraft tire bead structure for large sinkage according to claim 1, characterized in that: An adhesive is provided between the entire triangular cross-section filling glue (2) and the circular cross-section steel ring (1).

9. The radial aircraft tire bead structure for large sinkage according to claim 1, characterized in that: The elastic modulus of the inner filling rubber part (201) of the triangular cross-section filling rubber (2), the elastic modulus of the outer filling rubber part (202) of the triangular cross-section filling rubber (2), the elastic modulus of the carcass cord layer (3) and the elastic modulus of the supporting rubber layer (402) decrease in sequence; The Shore A hardness of the inner filling rubber part (201) of the triangular cross-section filling rubber (2), the Shore A hardness of the outer filling rubber part (202) of the triangular cross-section filling rubber (2), the Shore A hardness of the carcass cord layer (3) and the Shore A hardness of the supporting rubber layer (402) decrease in sequence.

10. A radial aircraft tire bead structure for large sinkage according to claim 9, characterized in that: The Shore A hardness of the inner filling glue part (201) of the triangular cross-section filling glue (2) is 75-85 degrees, and the Shore A hardness of the outer filling glue part (202) of the triangular cross-section filling glue (2) is 69-75 degrees.

Images