Bias tire for aircraft

Abstract

A bias tire for an aircraft according to the present invention comprises a carcass made of two or more carcass plies toroidally extending between a pair of bead parts. The two or more carcass plies are made of organic fiber cords coated with rubber. The organic fiber cords extend between adjacent carcass plies at inclinations in mutually opposite directions relative to the tire equatorial plane. The bias tire for an aircraft is provided with an electronic component. The electronic component has one or more antennas. The antennas extend at an inclination angle of 32-90° with respect to the tire width direction.

Description

Aircraft bias tires

[0001] The present invention relates to a bias tire for an aircraft.

[0002] Conventionally, electronic components have been placed in tires, such as radio frequency (RF) ID tags, and tire management and other operations can be performed by storing information in the RFID tag via wireless communication and reading the stored information (see, for example, Patent Document 1).

[0003] JP 2011-178388 A

[0004] When an aircraft bias tire is equipped with an electronic device (especially an RFID tag having an antenna, etc.), the electronic device may be damaged.

[0005] An object of the present invention is to provide a bias tire for aircraft that can prevent damage to electronic devices disposed in the tire.

[0006] The gist of the present invention is as follows: (1) An aircraft bias tire including a pair of bead portions, a pair of sidewall portions connected to the pair of bead portions, a tread portion connected between the pair of sidewall portions, and a carcass consisting of two or more carcass plies toroidally spanning the pair of bead portions, wherein the two or more carcass plies are formed of rubber-coated organic fiber cords, and the organic fiber cords extend between adjacent carcass plies at an inclination in opposite directions relative to the tire equatorial plane, and the aircraft bias tire is equipped with an electronic component, the electronic component having one or more antennas, and the antennas extend at an inclination angle of 32 to 90 degrees relative to the tire width direction.

[0007] In this specification, the "central region of the tread width in the tire width direction" refers to the central 40% region between the tread edges when an aircraft bias tire is mounted on an applicable rim, inflated to a specified internal pressure, and no load is applied. The "tread edge" refers to the outermost point in the tire width direction of the surface that will come into contact with the road surface when an aircraft bias tire is mounted on an applicable rim, inflated to a specified internal pressure, and subjected to a maximum load.

[0008] In this specification, the term "applicable rim" refers to the standard rim (referred to as "Measuring Rim" in the ETRTO STANDARDS MANUAL and "Design Rim" in the TRA YEAR BOOK) for the applicable size, which is an industrial standard valid in the region where the tire is produced and used, and which is described in the JATMA YEAR BOOK of the Japan Automobile Tire Manufacturers Association (JATMA) in Japan, the STANDARDS MANUAL of the European Tire and Rim Technical Organization (ETRTO) in Europe, and the YEAR BOOK of the Tire and Rim Association, Inc. (TRA) in the United States, or which will be described in the future. "rim" refers to the rim (i.e., the above "rim" includes not only current sizes but also sizes that may be included in the above industry standards in the future. An example of a "size to be described in the future" is a size listed under "FUTURE DEVELOPMENTS" in the 2013 edition of ETRTO). However, for sizes not listed in the above industry standards, it refers to a rim with a width corresponding to the bead width of the tire. Furthermore, "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity of a single wheel for the applicable size / ply rating listed in the above JATMA etc., and for sizes not listed in the above industry standards, "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity specified for each vehicle on which the tire is mounted. Furthermore, "maximum applied load" refers to the load corresponding to the above maximum load capacity.

[0009] According to the present invention, it is possible to provide an aircraft bias tire that can prevent damage to electronic devices disposed in the tire.

[0010] It is a tire width direction cross-sectional view of an aircraft bias tire according to one embodiment of the present invention. It is a diagram for explaining pantograph deformation. It is a diagram for explaining a compressive force acting on an antenna of an electronic component. It is a schematic plan view showing an example of an electronic component. It is a schematic plan view showing the arrangement of the electronic component.

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0012] Fig. 1 is a widthwise cross-sectional view of an aircraft bias tire according to one embodiment of the present invention. As shown in Fig. 1, this aircraft bias tire (hereinafter also simply referred to as "tire") 1 includes a pair of bead portions 2, a pair of sidewall portions 3 connected to the pair of bead portions 2, a tread portion 4 connected between the pair of sidewall portions 3, and a carcass 5 consisting of two or more carcass plies toroidally straddling the pair of bead portions 2. This tire is configured to function when inflated to an internal pressure of 145 psi or more when assembled on a rim.

[0013] In the illustrated example, three bead cores 2a to 2c are embedded in the bead portion 2. The number of bead cores is preferably set to correspond to the number of carcass plies, which is two or more.

[0014] In this example, the carcass 5 is composed of three carcass plies 5a to 5c. Each carcass ply is made of rubber-coated organic fiber cords. The organic fiber cords are not particularly limited, but may be cords made of nylon, aramid, or the like. The organic fiber cords extend inclined in opposite directions (at the same angle with respect to the tire equatorial plane CL in this example) between adjacent carcass plies (between 5a and 5b and between 5b and 5c in the illustrated example) with respect to the tire equatorial plane CL. As illustrated, the carcass ply 5a has a carcass turn-up portion folded back around the bead core 2a. Similarly, the carcass ply 5b has a carcass turn-up portion folded back around the bead core 2b, and the carcass ply 5c has a carcass turn-up portion folded back around the bead core 2c.

[0015] The tire 1 further includes an electronic component 6. In this example, the electronic component 6 is an RFID tag. In the illustrated example, the tire has the electronic component 6 disposed on the surface of the tire 1, more specifically, on the inner surface of an inner liner disposed on the inner surface of the tire. In the illustrated example, the electronic component 6 is disposed in a central region of the tread width in the tire width direction.

[0016] FIG. 4 is a schematic plan view showing an example of an electronic component (RFID tag) 6. As shown in FIG. 4, the electronic component (RFID tag) 6 has one or more antennas 6a, 6b (two in the illustrated example). The antennas 6a, 6b extend in a predetermined direction (linearly in the illustrated example). The antennas may also extend in a predetermined direction while bending in a wave-like manner, for example. The electronic component (RFID tag) 6 has a substrate 6c. An RFID chip and the like are embedded in the substrate 6c. Although not shown, the substrate 6c is preferably covered with an exterior body to protect the RFID chip and the like. At least a portion of the electronic component (RFID tag) 6 is preferably covered with a cover rubber in consideration of adhesion to the tire rubber.

[0017] 5 is a schematic plan view showing the arrangement of the electronic component (RFID tag) 6. The antennas 6a, 6b extend at an inclination angle of 32 to 90 degrees relative to the tire width direction. It is more preferable that the antennas 6a, 6b extend at an inclination angle of 40 to 90 degrees relative to the tire width direction, and even more preferable that the antennas 6a, 6b extend at an inclination angle of 90 degrees relative to the tire width direction (i.e., extend without inclination relative to the tire circumferential direction) as shown in the illustrated example. The effects of the aircraft bias tire of this embodiment will be described below.

[0018] The inventors of the present invention have investigated the causes of damage to electronic devices mounted on aircraft bias tires and found that compressive force due to pantograph deformation of the carcass ply in aircraft bias tires, which are subject to high loads, can cause antenna damage. As shown in Figure 2, when a tire is loaded, pantograph deformation generates tensile force in the tire circumferential direction, and when the tire internal pressure increases or the load is released, pantograph deformation generates compressive force in the tire width direction. In contrast, if an antenna extends in the tire width direction or at a low angle relative to the tire width direction, compressive strain due to the compressive force acts significantly on the antenna, causing it to break or otherwise be damaged, as shown in Figure 3. This effect is particularly pronounced in aircraft tires, where the tire internal pressure is high and the load on the tire fluctuates significantly during takeoff and landing.

[0019] In contrast, in the aircraft bias tire 1 of this embodiment, the antennas 6a, 6b extend at an inclination angle of 32 to 90 degrees relative to the tire width direction. As a result, the extension direction of the antennas 6a, 6b is inclined with respect to the tire width direction, which is the direction in which the compressive force acts, so that the compressive strain acting on the antennas 6a, 6b can be reduced. As described above, the aircraft bias tire 1 of this embodiment can prevent damage to the electronic device 6 placed in the tire.

[0020] For the same reasons as above, it is more preferable that the antennas 6a, 6b extend at an inclination angle of 40 to 90 degrees with respect to the tire width direction, and it is even more preferable that they extend at an inclination angle of 90 degrees with respect to the tire width direction.

[0021] On the other hand, if the tensile force acts on the end of the cover rubber of the electronic component 6, it may cause the electronic component 6 to peel off from the surface of the tire 1. Therefore, in order to ensure adhesion of the electronic component 6 to the tire 1 when the electronic component 6 is disposed on the tire surface, the antennas 6 a, 6 b are preferably inclined at an angle of 32° or more and less than 90° with respect to the tire width direction, and more preferably at an angle of 32° or more and 85° or less.

[0022] The electronic components 6 are preferably disposed on the surface of the aircraft bias tire 1. By disposing the electronic components 6 away from the carcass ply, the compressive force is less likely to act on the electronic components 6, and damage to the electronic devices 6 can be further suppressed. On the other hand, in the present disclosure, the electronic components 6 can also be disposed inside the aircraft bias tire 1. In this case, the problem of the electronic components 6 peeling off from the surface of the tire 1 does not occur.

[0023] It is preferable that at least a part of the electronic component 6 is covered with a cover rubber, since this facilitates adhesion to the tire rubber.

[0024] The electronic components 6 are preferably disposed in the central region of the tread width in the tire width direction. This is because bias tires generally have a cross-sectional shape with a large curvature, and therefore the electronic components 6 have a higher adhesiveness to the tire in the central region of the tread width in the tire width direction.

[0025] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. For example, the tire 1 may include one or more reinforcing layers, such as a breaker layer, on the tire radially outer side of the carcass 5. In this case, it is preferable that the cords of the reinforcing layers, such as the breaker layer, are non-metallic (e.g., organic fibers) in consideration of the communication properties of the electronic components 6. Examples of the present invention will be described below, but the present invention is not limited to the following examples.

[0026] In order to confirm the effects of the present invention, a test was conducted to evaluate the antenna durability of an RFID tag having two antennas, using examples and comparative examples in which the inclination angle of the antenna relative to the tire width direction was varied. The test type was in accordance with TSO-C62. The tire size was H44.5 x 16.5-21, the specified load was 20,280 kgf, and the specified internal pressure was 1,480 kPa. Table 1 shows the test results. Note that the "inclination angle" in Table 1 refers to the inclination angle of the antenna relative to the tire width direction.

[0027]

[0028] As shown in Table 1, in both Comparative Examples 1 and 2, the antenna broke, but in both Inventive Examples 1 and 2, no failure was observed in the antenna, and good durability was demonstrated.

[0029] 1: Aircraft bias tire (tire), 2: Bead portion, 2a to 2c: Bead core, 3: Sidewall portion, 4: Tread portion, 5: Carcass, 5a to 5c: Carcass ply, 6: Electronic component (RFID tag), 6a, 6b: Antenna, 6c: Substrate

Claims

1. An aircraft bias tire comprising: a pair of bead portions; a pair of sidewall portions connected to the pair of bead portions; a tread portion connected between the pair of sidewall portions; and a carcass consisting of two or more carcass plies toroidally spanning the pair of bead portions, wherein the two or more carcass plies are made of rubber-coated organic fiber cords, and the organic fiber cords extend between adjacent carcass plies at an inclination in opposite directions relative to the tire equatorial plane, and the aircraft bias tire is equipped with electronic components, each of which has one or more antennas, and the antennas extend at an inclination angle of 32 to 90 degrees relative to the tire width direction.

2. An aircraft bias tire according to claim 1, wherein the antenna extends at an angle of 40 to 90 degrees relative to the tire width direction.

3. An aircraft bias tire according to claim 1 or 2, wherein the electronic components are disposed on the surface of the aircraft bias tire.

4. An aircraft bias tire according to any one of claims 1 to 3, wherein at least a portion of the electronic components is covered with a cover rubber.

5. An aircraft bias tire according to any one of claims 1 to 4, wherein the electronic components are arranged in a central region of the tread portion in the tire width direction.

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