JP2021112932A - Pneumatic tire - Google Patents

Abstract

To provide a pneumatic tire, the durability of which can be improved while the communication property and flaw resistance of a transponder are improved.SOLUTION: An inner surface of a tire is provided with a transponder 20 that is extended along a circumferential direction of the tire. The transponder 20 is arranged between a position P1 15 mm away from an upper end 5e of a bead core 5 toward the radial outside of the tire and a position P2 5 mm away from a terminal 7e of a belt layer 7 toward the radial inside of the tire.SELECTED DRAWING: Figure 2

Description

The present invention relates to a pneumatic tire on which a transponder is arranged, and more particularly to a pneumatic tire capable of improving the durability of the tire while improving the communication property and the trauma resistance of the transponder.

In a pneumatic tire, it has been proposed to embed an RFID tag (transponder) in the tire (see, for example, Patent Document 1). When the transponder is embedded in the tire, for example, if the transponder is placed between the carcass layer and the rubber layer of the sidewall or between the carcass layer and the inner liner layer, the effect of stress concentration when the tire touches the ground causes the tire to have a transponder. There is a problem that durability deteriorates. Further, if the transponder is arranged near a metal tire component (for example, a bead core or the like), there is a problem that the tire component and the transponder interfere with each other and the communication property of the transponder deteriorates. Further, if the transponder is arranged outside the winding portion of the carcass layer in the tire width direction, the transponder may be damaged due to the damage of the sidewall portion.

Japanese Unexamined Patent Publication No. 7-137510

An object of the present invention is to provide a pneumatic tire capable of improving the durability of a tire while improving the communication property and the trauma resistance of the transponder.

In order to achieve the above object, the pneumatic tire of the present invention includes a tread portion extending in the tire circumferential direction to form an annular shape, a pair of sidewall portions arranged on both sides of the tread portion, and these sidewall portions. A pair of bead portions arranged inside in the tire radial direction are provided, a bead filler is arranged on the outer periphery of the bead core of each bead portion, and at least one carcass layer is mounted between the pair of bead portions. In a pneumatic tire in which a plurality of belt layers are arranged on the outer peripheral side of the carcass layer in the tread portion, a transponder extending along the tire circumferential direction is provided on the inner surface of the tire, and the transponder extends from the upper end of the bead core to the tire. It is characterized in that it is arranged between a position of 15 mm on the outer side in the radial direction and a position of 5 mm on the inner side in the radial direction of the tire from the end of the belt layer.

In the present invention, a transponder extending along the tire circumferential direction is provided on the inner surface of the tire, and the transponder is located 15 mm outward in the tire radial direction from the upper end of the bead core and 5 mm inward in the tire radial direction from the terminal of the belt layer. Since the transponder is located between the tires, the transponder is located in a portion where the stress concentration is small when the tire touches the ground, and the adverse effect on the tire durability can be reduced, so that the tire durability can be improved. In addition, metal interference is unlikely to occur, and the communicability of the transponder can be ensured. Further, damage to the transponder due to damage to the sidewall portion can be prevented.

In the pneumatic tire of the present invention, it is preferable that the transponder is arranged between the position 5 mm outside the tire radial direction from the upper end of the bead filler and the position 5 mm inside the tire radial direction from the end of the belt layer. As a result, the transponder is arranged in the flex zone where the rubber gauge is thin, but since the radio wave is less attenuated during the communication of the transponder in this region, the communication property of the transponder can be effectively improved. In addition, damage to the transponder due to damage to the inner liner layer during rim assembly can be prevented.

It is preferable that the center of the transponder is arranged at a distance of 10 mm or more in the tire circumferential direction from the splice portion of the tire component member. Thereby, the durability of the tire can be effectively improved.

The distance between the center of the cross section of the transponder and the inner surface of the tire is preferably 1 mm or more. As a result, the durability of the tire can be effectively improved, and damage to the transponder due to damage to the inner liner layer during rim assembly can be prevented.

The transponder is coated with a coating layer, and the relative permittivity of the coating layer is preferably 7 or less. As a result, the transponder is protected by the coating layer, the durability of the transponder can be improved, the radio wave transmission of the transponder can be ensured, and the communication property of the transponder can be effectively improved.

The transponder is coated with a coating layer, and the thickness of the coating layer is preferably 0.5 mm to 3.0 mm. Thereby, the communication property of the transponder can be effectively improved.

The transponder has an IC board for storing data and an antenna for transmitting and receiving data, and the antenna is preferably spiral. As a result, it is possible to follow the deformation of the tire during running, and it is possible to improve the durability of the transponder.

It is a meridian semi-cross-sectional view which shows the pneumatic tire which comprises the embodiment of this invention. FIG. 5 is a cross-sectional view taken along the meridian line schematically showing the pneumatic tire of FIG. FIG. 5 is a cross-sectional view taken along the equator line schematically showing the pneumatic tire of FIG. FIG. 5 is an enlarged cross-sectional view showing a transponder arranged on the pneumatic tire of FIG. 1. (A) and (b) are perspective views which show the transponder which can be arranged in the pneumatic tire which concerns on this invention. It is explanatory drawing which shows the tire radial position of a transponder in a test tire.

Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings. FIGS. 1 to 4 show a pneumatic tire according to an embodiment of the present invention.

As shown in FIG. 1, the pneumatic tire of the present embodiment includes a tread portion 1 extending in the tire circumferential direction to form an annular shape, a pair of sidewall portions 2 arranged on both sides of the tread portion 1, and these. It includes a pair of bead portions 3 arranged inside the sidewall portion 2 in the tire radial direction.

At least one layer (one layer in FIG. 1) of the carcass layer 4 formed by arranging a plurality of carcass cords in the radial direction is mounted between the pair of bead portions 3. As the carcass cord constituting the carcass layer 4, an organic fiber cord such as nylon or polyester is preferably used. An annular bead core 5 is embedded in each bead portion 3, and a bead filler 6 made of a rubber composition having a triangular cross section is arranged on the outer periphery of the bead core 5.

On the other hand, a plurality of layers (two layers in FIG. 1) of belt layers 7 are embedded on the outer peripheral side of the tire of the carcass layer 4 in the tread portion 1. The belt layer 7 includes a plurality of reinforcing cords that are inclined with respect to the tire circumferential direction, and the reinforcing cords are arranged so as to intersect each other between the layers. In the belt layer 7, the inclination angle of the reinforcing cord with respect to the tire circumferential direction is set in the range of, for example, 10 ° to 40 °. As the reinforcing cord of the belt layer 7, a steel cord is preferably used.

On the outer peripheral side of the tire of the belt layer 7, at least one layer (two layers in FIG. 1) in which reinforcing cords are arranged at an angle of, for example, 5 ° or less with respect to the tire peripheral direction for the purpose of improving high-speed durability. The belt cover layer 8 is arranged. In FIG. 1, the belt cover layer 8 located inside the tire radial direction constitutes a full cover covering the entire width of the belt layer 7, and the belt cover layer 8 located outside the tire radial direction covers only the end portion of the belt layer 7. It constitutes an edge cover layer. As the reinforcing cord of the belt cover layer 8, an organic fiber cord such as nylon or aramid is preferably used.

In the pneumatic tire, both terminals 4e of the carcass layer 4 are arranged so as to be folded back from the inside to the outside of each bead core 5 and to wrap the bead core 5 and the bead filler 6. The carcass layer 4 is wound around the bead core 5 in each bead portion 3 and the main body portion 4A which is a portion extending from the tread portion 1 through each sidewall portion 2 to each bead portion 3, and is wound up on each sidewall portion 2 side. It includes a winding portion 4B which is a portion extending toward the direction.

Further, the inner liner layer 9 is arranged along the carcass layer 4. That is, the inner liner layer 9 forms the inner surface of the tire. A cap tread rubber layer 11 is arranged on the tread portion 1, a sidewall rubber layer 12 is arranged on the sidewall portion 2, and a rim cushion rubber layer 13 is arranged on the bead portion 3. The rubber layer 10 arranged on the outside of the carcass layer 4 in the sidewall portion 2 includes the sidewall rubber layer 12 and the rim cushion rubber layer 13.

Further, in the pneumatic tire, the transponder 20 is arranged on the inner surface of the tire, that is, inside the inner liner layer 9. At the time of tire molding, the transponder 20 is vulcanized and adhered to the inner surface of the tire via, for example, a rubber layer, and is integrally attached to the inner surface of the tire (inner liner layer 9). Further, the transponder 20 has a position P1 15 mm outward in the tire radial direction from the upper end 5e (outer end in the tire radial direction) of the bead core 5 and a position P1 in the tire radial direction from the terminal 7e of the belt layer 7 as an arrangement area in the tire radial direction. It is arranged inside at a position P2 of 5 mm. That is, the transponder 20 is arranged in the region S1 shown in FIG. Further, the transponder 20 extends along the tire circumferential direction. The transponder 20 may be arranged so as to be inclined in a range of −10 ° to 10 ° with respect to the tire circumferential direction.

As the transponder 20, for example, an RFID (Radio Frequency Identification) tag can be used. As shown in FIGS. 5A and 5B, the transponder 20 has an IC substrate 21 for storing data and an antenna 22 for transmitting and receiving data in a non-contact manner. By using such a transponder 20, it is possible to write or read information about the tire in a timely manner and efficiently manage the tire. RFID is an automatic recognition technology that is composed of a reader / writer having an antenna and a controller, an IC board, and an ID tag having an antenna, and can communicate data wirelessly.

The overall shape of the transponder 20 is not particularly limited, and for example, a columnar or plate-shaped transponder can be used as shown in FIGS. 5A and 5B. In particular, when the columnar transponder 20 shown in FIG. 5A is used, it is preferable because it can follow the deformation of the tire in each direction. In this case, the transponder 20's antenna 22 protrudes from each of both ends of the IC substrate 21 and has a spiral shape. As a result, it is possible to follow the deformation of the tire during traveling, and it is possible to improve the durability of the transponder 20. Further, communication can be ensured by appropriately changing the length of the antenna 22.

In the above-mentioned pneumatic tire, a transponder 20 extending along the tire circumferential direction is provided on the inner surface of the tire, and the transponder 20 is located at a position P1 15 mm outward in the tire radial direction from the upper end 5e of the bead core 5 and the terminal 7e of the belt layer 7. Since the transponder 20 is located between the tire and the position P2 5 mm inward in the radial direction of the tire, the transponder 20 is located in a portion where stress concentration is low when the tire touches the ground, and the adverse effect on the tire durability can be reduced. Can be improved. In addition, metal interference is unlikely to occur, and the communicability of the transponder 20 can be ensured. Further, damage to the transponder 20 due to damage to the sidewall portion 2 can be prevented.

Here, if the transponder 20 is arranged inside the tire radial direction from the position P1, metal interference with the rim flange occurs, and the communication property of the transponder 20 tends to deteriorate. Further, when the transponder 20 is arranged outside the position P2 in the tire radial direction, metal interference with the belt layer 7 occurs, and the communication property of the transponder 20 tends to deteriorate.

In the pneumatic tire, the transponder 20 is arranged between the position P3 5 mm outside the tire radial direction from the upper end 6e of the bead filler 6 and the position P2 5 mm inside the tire radial direction from the terminal 7e of the belt layer 7. It is good to have it. That is, it is preferable that the transponder 20 is arranged in the region S2 shown in FIG. The area S2 is a flex zone having a thin rubber gauge, but when the transponder 20 is arranged in the area S2, the attenuation of radio waves during communication of the transponder 20 is reduced, and the communication property of the transponder 20 can be effectively improved. .. Further, it is possible to prevent damage to the transponder 20 due to damage to the inner liner layer 9 when assembling the rim.

As shown in FIG. 3, there are a plurality of splice portions on the tire circumference in which the ends of the tire constituent members are overlapped with each other. FIG. 3 shows the position Q of each splice portion in the tire circumferential direction. The center of the transponder 20 is preferably arranged at a distance of 10 mm or more in the tire circumferential direction from the splice portion of the tire component member. That is, it is preferable that the transponder 20 is arranged in the region S3 shown in FIG. Specifically, it is preferable that the IC substrate 21 constituting the transponder 20 is separated from the position Q by 10 mm or more in the tire circumferential direction. Further, it is more preferable that the entire transponder 20 including the antenna 22 is separated from the position Q in the tire circumferential direction by 10 mm or more, and the entire transponder 20 in the state of being covered with the covering rubber is in the tire circumferential direction from the position Q. Most preferably, they are separated by 10 mm or more. Further, as the tire constituent member arranged apart from the transponder 20, it is preferable that the inner liner layer 9 or the carcass layer 4 is arranged adjacent to the transponder 20. By arranging the transponder 20 away from the splice portion of the tire constituent member in this way, the durability of the tire can be effectively improved.

In the embodiment of FIG. 3, an example is shown in which the positions Q of the splice portions of the tire constituent members in the tire circumferential direction are arranged at equal intervals, but the present invention is not limited to this. The position Q in the tire circumferential direction can be set to an arbitrary position, and in any case, the transponder 20 is arranged so as to be separated from the splice portion of each tire component by 10 mm or more in the tire circumferential direction.

As shown in FIG. 4, the distance d between the cross-sectional center of the transponder 20 and the inner surface of the tire is preferably 1 mm or more. By separating the transponder 20 from the inner surface of the tire in this way, the durability of the tire can be effectively improved, and damage to the transponder 20 due to damage to the inner liner layer 9 during rim assembly can be prevented. Can be done.

Further, the transponder 20 is preferably covered with a coating layer 23. The coating layer 23 covers the entire transponder 20 so as to sandwich both the front and back surfaces of the transponder 20. The coating layer 23 may be made of rubber having the same physical characteristics as the rubber constituting the tire constituent members such as the sidewall rubber layer 12 and the rim cushion rubber layer 13, or may be made of rubber having different physical characteristics. Since the transponder 20 is protected by the coating layer 23 in this way, the durability of the transponder 20 can be improved.

In the pneumatic tire, the relative permittivity of the coating layer 23 is preferably 7 or less, and more preferably 2 to 5 in a state where the transponder 20 is covered with the coating layer 23. By appropriately setting the relative permittivity of the coating layer 23 in this way, it is possible to secure radio wave transmission when the transponder 20 radiates radio waves and effectively improve the communication property of the transponder 20. The relative permittivity of the rubber constituting the coating layer 23 is a relative permittivity of 860 MHz to 960 MHz at room temperature. Here, the normal temperature conforms to the standard state of the JIS standard, and is 23 ± 2 ° C. and 60% ± 5% RH. The relative permittivity of the rubber is measured after being treated at 23 ° C. and 60% RH for 24 hours. The above-mentioned range of 860 MHz to 960 MHz corresponds to the current assigned frequency of RFID in the UHF band, but when the above-mentioned allotted frequency is changed, the relative permittivity of the allotted frequency range may be defined as described above.

Further, in a state where the transponder 20 is covered with the coating layer 23, the thickness t of the coating layer 23 is preferably 0.5 mm to 3.0 mm, more preferably 1.0 mm to 2.5 mm. Here, the thickness t of the coating layer 23 is the rubber thickness at the position including the transponder 20, for example, as shown in FIG. 4, the thickness on a straight line passing through the center of the transponder 20 and orthogonal to the inner surface of the tire. It is a rubber thickness which is the sum of the thickness t1 and the thickness t2. By appropriately setting the thickness t of the coating layer 23 in this way, the communicability of the transponder 20 can be effectively improved. Here, if the thickness t of the coating layer 23 is thinner than 0.5 mm, the effect of improving the communication property of the transponder 20 cannot be obtained, and conversely, if the thickness t of the coating layer 23 exceeds 3.0 mm, The coating layer 23 including the transponder 20 protrudes excessively from the inner surface of the tire, which is not preferable. The cross-sectional shape of the covering layer 23 is not particularly limited, but for example, a triangular shape, a rectangular shape, a trapezoidal shape, or a spindle shape can be adopted. The coating layer 23 of FIG. 4 has a rectangular cross-sectional shape.

In the above-described embodiment, an example of a pneumatic tire having one carcass layer has been shown, but the tire is not particularly limited, and may have two carcass layers. Further, in the above-described embodiment, an example is shown in which the terminal 4e of the winding portion 4B of the carcass layer 4 is arranged in the middle of the sidewall portion 2 beyond the upper end 6e of the bead filler 6, but the present invention is limited to this. Instead, it can be placed at any height.

With a tire size of 265 / 40ZR20, a tread portion extending in the tire circumferential direction to form an annular shape, a pair of sidewall portions arranged on both sides of the tread portion, and these sidewall portions are arranged inside the tire radial direction. A pair of bead portions are provided, a bead filler is arranged on the outer periphery of the bead core of each bead portion, a carcass layer is mounted between the pair of bead portions, and a plurality of belt layers are mounted on the outer peripheral side of the carcass layer in the tread portion. In the pneumatic tire in which the tire is arranged, a transponder extending along the tire circumferential direction is provided, and the position of the transponder (tire width direction, tire radial direction and tire circumferential direction), the distance between the transponder and the inner surface of the tire, and the covering layer. The tires of Comparative Examples 1 to 5 and Examples 1 to 14 in which the specific dielectric constant, the thickness of the coating layer, and the form of the transponder were set as shown in Tables 1 and 2 were manufactured.

In Tables 1 and 2, when the position of the transponder (in the tire width direction) is "W", the transponder is arranged on the inner surface of the tire (inside the inner liner layer), and the position of the transponder (in the tire width direction) is "X". In the case of ", the transponder is placed between the carcass layer and the inner liner layer, and when the position of the transponder (in the tire width direction) is" Y ", the transponder is placed between the carcass layer and the sidewall rubber layer. When the transponder is placed in contact with the layer and the position of the transponder (in the tire width direction) is "Z", it means that the transponder is placed in contact with the rim cushion rubber layer between the carcass layer and the rim cushion rubber layer. show. Further, in Tables 1 and 2, the positions of the transponders (in the tire radial direction) correspond to the respective positions A to E shown in FIG. Further, in Tables 1 and 2, the position of the transponder (tire circumferential direction) indicates the distance [mm] measured in the tire circumferential direction from the center of the transponder to the splice portion of the tire component member.

For these test tires, tire evaluation (durability) and transponder evaluation (communication, durability, trauma resistance and damage resistance) were carried out by the following test methods, and the results are shown in Tables 1 and 2. rice field.

Durability (tires and transponders):
After assembling each test tire to the wheel of the standard rim and conducting a running test with a drum tester under the conditions of an air pressure of 120 kPa, 102% of the maximum load, and a running speed of 81 km, running when a tire failure occurs. The distance was measured. The evaluation results are indicated by "◎ (excellent)" when the mileage reaches 6480 km, "○ (good)" when the mileage is 4050 km or more and less than 6480 km, and when the mileage is 3240 km or more and less than 4050 km. Is indicated by "Δ (possible)", and the case where the mileage is less than 3240 km is indicated by four stages of "x (impossible)". Further, after the running was completed, the outer surface of each test tire was visually inspected to confirm whether or not the tire failure originated from the transponder. The evaluation result showed the presence or absence of the failure.

Communication (transponder):
For each test tire, communication work with the transponder was carried out using a reader / writer. Specifically, the maximum distance that can be communicated with a reader / writer with an output of 250 mW and a carrier frequency of 860 MHz to 960 MHz was measured. The evaluation results are indicated by "◎ (excellent)" when the communication distance is 500 mm or more, "○ (good)" when the communication distance is 150 mm or more and less than 500 mm, and "△ (△) when the communication distance is less than 150 mm. Yes) ”was shown in three stages.

Trauma resistance (transponder):
Each test tire was assembled to a standard rim wheel, mounted on a test vehicle, and a running test was conducted in which the tire rides on a curb with a height of 100 mm under the conditions of an air pressure of 230 kPa and a running speed of 20 km / h. After running, it was confirmed that the outer surface of the tire corresponding to the location of the transponder was damaged. The evaluation results showed the presence or absence of damage to the outer surface of the tire due to the placement of the transponder.

Damage resistance when assembling the rim (transponder):
For each test tire, the inner surface of the tire corresponding to the location of the transponder was visually inspected when the rim was replaced. The evaluation results showed the presence or absence of damage to the transponder due to damage to the inner liner.

As can be seen from Tables 1 and 2, the pneumatic tires of Examples 1 to 14 have improved tire durability, transponder communication, and transponder trauma resistance in a well-balanced manner. In the pneumatic tire of Example 6, since the distance between the center of the transponder and the inner surface of the tire was set to be long, the damage resistance of the transponder was improved. In the pneumatic tire of Example 13, since the thickness of the coating layer covering the transponder was set to be thick, the amount of protrusion of the coating layer including the transponder from the inner surface of the tire was large, and the tire was easily damaged even when the rim was assembled. Since the pneumatic tire of Example 14 used a columnar transponder, the durability of the transponder was improved, and there was no failure starting from the transponder.

On the other hand, in Comparative Examples 1 to 3, the transponder was embedded in the tire, and the durability of the tire deteriorated due to the influence of stress concentration when the tire touched down. In Comparative Examples 1 to 5, since the position of the transponder in the tire radial direction deviates from the region specified in the present invention, the communication property of the transponder deteriorates. In Comparative Examples 1 and 2, since the transponder was arranged between the carcass layer and the sidewall rubber layer or the rim cushion rubber layer in contact with the rubber layer, the traumatic resistance of the transponder deteriorated.

1 Tread part 2 sidewall part 3 bead part 4 carcass layer 4A main body part 4B winding part 5 bead core 6 bead filler 7 belt layer 20 transponder CL tire center line P1 to P3 position

Claims (7)

A tread portion extending in the tire circumferential direction to form an annular shape, a pair of sidewall portions arranged on both sides of the tread portion, and a pair of bead portions arranged inside the tire radial direction of these sidewall portions. A bead filler is arranged on the outer periphery of the bead core of each bead portion, at least one carcass layer is mounted between the pair of bead portions, and a plurality of layers of belts are mounted on the outer peripheral side of the carcass layer in the tread portion. In pneumatic tires with layers
A transponder extending along the tire circumferential direction is provided on the inner surface of the tire, and the transponder is located 15 mm outward in the tire radial direction from the upper end of the bead core and 5 mm inward in the tire radial direction from the terminal of the belt layer. Pneumatic tires characterized by being placed in between. The first aspect of claim 1, wherein the transponder is arranged between a position 5 mm outward in the tire radial direction from the upper end of the bead filler and a position 5 mm inward in the tire radial direction from the end of the belt layer. Pneumatic tires. The pneumatic tire according to claim 1 or 2, wherein the center of the transponder is arranged at a distance of 10 mm or more in the tire circumferential direction from the splice portion of the tire component member. The pneumatic tire according to any one of claims 1 to 3, wherein the distance between the cross-sectional center of the transponder and the inner surface of the tire is 1 mm or more. The pneumatic tire according to any one of claims 1 to 4, wherein the transponder is coated with a coating layer, and the relative permittivity of the coating layer is 7 or less. The pneumatic tire according to any one of claims 1 to 5, wherein the transponder is coated with a coating layer, and the thickness of the coating layer is 0.5 mm to 3.0 mm. The pneumatic tire according to any one of claims 1 to 6, wherein the transponder has an IC substrate for storing data and an antenna for transmitting and receiving data, and the antenna has a spiral shape.

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