WO2017130956A1 - Tire with embedded rfid tag - Google Patents

Tire with embedded rfid tag Download PDF

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Publication number
WO2017130956A1
WO2017130956A1 PCT/JP2017/002328 JP2017002328W WO2017130956A1 WO 2017130956 A1 WO2017130956 A1 WO 2017130956A1 JP 2017002328 W JP2017002328 W JP 2017002328W WO 2017130956 A1 WO2017130956 A1 WO 2017130956A1
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WO
WIPO (PCT)
Prior art keywords
antenna
tire
rfid tag
carcass ply
rfid
Prior art date
Application number
PCT/JP2017/002328
Other languages
French (fr)
Japanese (ja)
Inventor
大祐 田村
恵市 酒井
大石　教博
義博 水沼
Original Assignee
トッパン・フォームズ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2016011786A external-priority patent/JP6612141B2/en
Priority claimed from JP2016011787A external-priority patent/JP6650767B2/en
Application filed by トッパン・フォームズ株式会社 filed Critical トッパン・フォームズ株式会社
Publication of WO2017130956A1 publication Critical patent/WO2017130956A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C19/00—Tyre parts or constructions not otherwise provided for
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
    • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
    • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
    • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
    • G06K19/077—Constructional details, e.g. mounting of circuits in the carrier

Definitions

  • the present invention relates to a tire incorporating an RFID tag.
  • This application claims priority based on Japanese Patent Application No. 2016-011786 filed in Japan on January 25, 2016 and Japanese Patent Application No. 2016-011787 filed in Japan on January 25, 2016. The contents are incorporated here.
  • an RFID tag including an RFID chip and an external antenna (dipole antenna) connected to an antenna pin of the RFID chip is embedded in a tire, and the RFID tag, the external antenna, The conductive carcass ply cord is electromagnetically coupled.
  • a transponder in which a circuit board having a transmission / reception function and a storage function and an antenna coil are integrated in a cylindrical container (see, for example, Patent Document 3).
  • the dipole antenna and the carcass ply are electromagnetically coupled. For this reason, it is possible to ensure a sufficient communication distance.
  • a dipole antenna has been provided in the vicinity of the bead portion. For this reason, when the tire is greatly deformed, such as when the rim is assembled or when the protrusion is mounted, a load is applied, and the joint between the RFID chip and the antenna or the antenna pin and the external antenna may be damaged. As a result, communication cannot be performed, and as a result, information stored in the RFID chip cannot be read.
  • Patent Document 2 since the optimal positional relationship between the external antenna and the carcass ply cord is not clear, it is difficult to secure a sufficient communication distance depending on the position of the external antenna.
  • the joint between the RFID chip and the antenna is not easily damaged.
  • a special reading device reader
  • the identification mark is provided in the tire outer surface of the site
  • the vehicle must be stopped so that the position of the identification mark is easy to see, and the operability is poor.
  • the present invention has been made in view of conventional problems, and an object of the present invention is to provide a tire with a built-in RFID tag that can secure a sufficient communication distance and is excellent in durability.
  • the first aspect of the present invention is the following RFID tag built-in tire.
  • an RFID tag including an RFID chip and an antenna is a built-in tire,
  • the tire has a carcass ply having a conductive carcass ply cord;
  • the RFID chip and the first antenna are fixed to a first fixing member of the RFID tag;
  • the RFID tag is From the carcass ply end of the tire, disposed at a position outside the tire radial direction,
  • the second antenna is An RFID tag-embedded tire characterized by being electromagnetically coupled to a conductive carcass ply cord constituting the carcass ply.
  • the first aspect of the present invention preferably has the following features. These features are also preferably used in combination with each other.
  • the extension direction of the second antenna and the extension direction of the carcass ply cord are preferably orthogonal.
  • the shape of the portion of the second antenna that is away from the first antenna by a predetermined distance or more is preferably a wave shape. It is preferable that the length of the portion of the second antenna that is within a predetermined distance from the first antenna is half or more of the outer circumference of the first antenna.
  • the second aspect of the present invention is the following RFID tag built-in tire. That is, a tire with a built-in RFID tag including an RFID chip and an antenna,
  • the carcass ply of the tire has a conductive carcass ply cord, A first antenna connected to the RFID chip; A second antenna provided outside the first antenna and electromagnetically coupled to the first antenna;
  • the distance between the second antenna and the carcass ply cord is D
  • the overlapping area between the second antenna and the carcass ply cord is A
  • the area of the second antenna is S
  • the overlapping area A is the second
  • the communication distance evaluation value P is 2 or more and 72.
  • the second aspect of the present invention preferably has the following features. These features are also preferably used in combination with each other.
  • the P is preferably 3 or more and less than 52. It is preferable that the extending direction of the second antenna is orthogonal to the extending direction of the carcass ply cord. It is preferable that the shape of the second antenna is a wave shape.
  • first and second aspects of the invention may share each other's characteristics and preferable characteristics as long as there is no particular problem.
  • the present invention provides a tire with a built-in RFID tag that can secure a sufficient communication distance and has excellent durability.
  • the antenna 12 are composed of a first antenna 16 connected to the RFID chip 11 and a second antenna 17 provided outside the first antenna 16 and electromagnetically coupled to the first antenna 16.
  • the RFID chip 11 and the first antenna 16 are fixed to the first fixing member 13, the RFID tag 10 is disposed on the outer side in the tire radial direction of the end of the carcass ply of the tire, and the second antenna 17 is attached to the carcass ply. It is electromagnetically coupled to the conductive carcass ply cord 7a.
  • the outer side in the tire radial direction of the end of the carcass ply of the tire in FIG. 1 can also be referred to as the vicinity where the bead core and the side wall portion are arranged.
  • the antenna since the antenna is electromagnetically coupled to the carcass ply cord as described above, a sufficient communication distance can be ensured.
  • the second antenna which is a part that is electromagnetically coupled to the carcass ply cord of the antenna, is electromagnetically coupled to the first antenna that is a part connected to the RFID chip of the antenna. They are not directly bonded.
  • the conventional joint is configured to eliminate a joint that is easily damaged when the tire is greatly deformed. Therefore, durability of the RFID tag is improved.
  • the second antenna and the extension direction of the carcass ply cord can be sufficiently electromagnetically coupled. Therefore, the communication distance of the RFID tag can be further increased.
  • “perpendicular” means that the angle formed by the extension direction of the second antenna and the extension direction of the carcass ply cord is in a range of approximately 90 ° (90 ° ⁇ 10 °).
  • the second antenna has a corrugated shape from both ends to the U-shaped portion. Therefore, damage to the antenna due to deformation can be reduced.
  • the length of the corrugated portion may be arbitrarily selected.
  • the length of the portion of the second antenna that is within a predetermined distance from the first antenna is not less than half the length of the outer periphery of the first antenna.
  • the carcass ply has a conductive carcass ply cord 7a, and the antenna 12 is provided to the first antenna 16 connected to the RFID chip 11 and to the first antenna 16 provided with electromagnetic waves.
  • the second antenna 17 is coupled to the second antenna 17.
  • the distance between the second antenna 17 and the carcass ply cord 7a is D
  • the overlapping area of the second antenna 16 and the carcass ply cord 7a is A
  • the area of the second antenna is S
  • the overlapping area A is the first
  • P is 2 ⁇ P ⁇ 72.
  • the area S and the overlapping area A of the second antenna indicate the area (projected area) of the orthogonal projection onto the surface formed by the carcass ply cord of the second antenna.
  • the second antenna and the carcass ply cord that are electromagnetically coupled to the carcass ply cord are electromagnetically coupled so that the communication distance evaluation value P is in the range of 2 ⁇ P ⁇ 72 and connected to the RFID chip of the antenna.
  • the first antenna and the second antenna, which are parts to be connected, were electromagnetically coupled (without mechanically coupling). As a result, a sufficient communication distance that can withstand practical use can be secured.
  • the RFID tag of the present invention does not have a joint that is easily damaged when the tire is greatly deformed, the durability can be greatly improved.
  • the P is 3 or more and less than 52, a communication distance that can be practically used can be obtained with certainty. Further, since the extension direction of the second antenna and the extension direction of the carcass ply cord are orthogonal, the deformation of the second antenna can be reduced, and as a result, the durability of the antenna is improved. In addition, since the second antenna has a corrugated shape, damage to the antenna due to deformation of the tire can be reduced.
  • FIG. 1 is a cross-sectional view showing a tire 1 which is a preferred example of the present invention.
  • the tire 1 has a substantially donut shape.
  • FIG. 1 shows one of the symmetric cross sections when the tire 1 is cut so that the cross section of the bead portion is shown and passes through the central axis of the tire.
  • 2 is a tread portion
  • 3 is a belt layer
  • 4 is a sidewall portion
  • 5 is a shoulder portion
  • 6 is a bead portion
  • 7 is a carcass ply
  • 10 is an RFID tag of the present invention.
  • the tread portion 2 is a portion where the tire 1 is in contact with the road surface, and is constituted by a thick rubber layer. A tread pattern is formed on the surface of the rubber layer.
  • the belt layer 3 is obtained by covering a cord with a rubber member. A plurality of layers are arranged between the tread portion 2 and the carcass ply 7 in order to have a “definite effect” that maintains rigidity in the tire circumferential direction.
  • the sidewall portion 4 is a rubber layer provided between the tread portion 2 and the bead portion 6.
  • the shoulder portion 5 is a rubber layer located on the side wall portion 4 side that is continuous with the same member as the tread portion 2.
  • the bead portion 6 includes a pair of bead cores 6 a and bead fillers 6 b, and is arranged symmetrically on the left and right with respect to a plane perpendicular to the tire central axis passing through the center of the tire 1. It is the part combined with the wheel.
  • the bead core 6a is a steel wire bundle formed in a ring shape and covered with a rubber member.
  • the bead filler 6b is a rubber member having a triangular cross section that is filled between the rubber layer of the sidewall portion 4, the bead core 6a, and the carcass ply 7 in order to give the bead portion 6 rigidity.
  • the carcass ply 7 includes a plurality of conductive cords (hereinafter referred to as carcass ply cords) 7a and a covering rubber 7b that covers the carcass ply cord 7a.
  • the carcass ply 7 is a member that forms a skeleton of the tire, is disposed between the pair of bead cores 6a, and is disposed so as to straddle the bead cores 6a. Both ends of the carcass ply 7 are bent around the bead core 6a from the inside to the outside of the tire 1 to form a bent portion 7c.
  • the carcass ply cord 7a is electromagnetically coupled to the antenna 12 of the RFID tag 10 via the rubber member constituting the bead filler 6b, which is a dielectric, and the covering rubber 7b. 7 a functions as an antenna of the RFID tag 10.
  • FIG. 2 shows a state in which the RFID tag 10 provided on the sidewall portion 4 is observed from the side surface side of the tire.
  • FIG. 2 shows a part of the side surface of the donut-shaped tire. The upper part of FIG. 2 is the side close to the tread part, and the lower part is the side close to the bead core.
  • the rubber layer of the sidewall portion 4 is omitted. As shown in FIGS.
  • the RFID tag 10 includes an RFID chip 11, an antenna 12 connected to the RFID chip 11, and first to third fixing members 13 to 15.
  • the RFID tag 10 is attached under the sidewall portion 4 of the tire 1, that is, inside, and communicates with a reader (not shown) (see FIG. 1).
  • the mounting position of the RFID tag 10 can be arbitrarily selected within the scope of the present invention. Although it is preferable to be provided in the side wall part 4, it is not limited to this.
  • the RFID tag of the present invention may be provided in either the inner shoulder region or the outer shoulder region of a tire.
  • the mounting position of the RFID tag 10 is, for example, a carcass ply disposed 30 mm above the bead core 6a, 10 mm below the upper end of the bead filler 6b, and below, as used in the embodiment.
  • a carcass ply disposed 30 mm above the bead core 6a, 10 mm below the upper end of the bead filler 6b, and below as used in the embodiment.
  • an arrangement on the outer side of the tire 4 mm away from the cord 7a may be mentioned.
  • the antenna 12 includes a first antenna 16 connected to the RFID chip 11 and a second antenna 17 provided outside the first antenna 16.
  • the first antenna 16 and the second antenna 17 are not directly connected.
  • the material of the antenna can be arbitrarily selected, and examples thereof include metals (antennas obtained by etching, antennas made of wires, etc.), conductive fibers, conductive pastes, and the like.
  • the diameter of the antenna can be arbitrarily selected.
  • the diameter of the second antenna is 0.1 mm to 5.0 mm, more preferably 0.2 mm to 1.0 mm.
  • the first antenna 16 is a double-loop antenna, each having a rectangle of a different size, for the purpose of expanding the bandwidth of the used frequency.
  • the antennas 16 and 17 are not limited to the shape shown in the figure.
  • the size of the inner rectangle is preferably 1 mm to 10 mm on one side, and more preferably 2 mm to 7 mm.
  • the size of the outer rectangle is preferably 2 mm to 12 mm on one side, and more preferably 4 mm to 7 mm.
  • the rectangle may be a rectangle or a square.
  • the ratio of the length of the inner rectangle to the length of the outer rectangle can also be arbitrarily selected, and examples thereof include 1: 1 to 3.
  • the RFID chip 11 and the first antenna 16 are formed on a first fixing member 13 which is a film-like substrate made of an arbitrary material such as PET (polyethylene terephthalate). Another example of the material for the film-like substrate is polyimide.
  • the first fixing member is not limited to a film shape, and may be formed directly on the second fixing member or a substrate shape.
  • the front side of the paper surface of FIGS. 2 and 3A to 3C is the tire outer surface side
  • the back side of the paper surface is the tire inner surface side.
  • the RFID chip 11 and the first antenna 16 are first fixed so that the RFID chip 11 and the first antenna 16 are positioned on the tire outer surface side
  • the first fixing member 13 is positioned on the tire inner surface side. Formed on member 13.
  • the second antenna 17 has a U-shaped (U-shaped or square shape with no side) electromagnetic field coupling portion 17a and a left-hand direction from both ends of the U-shaped. And a pair of extensions 17b extending rightward. Electromagnetic coupling can also be called electromagnetic coupling.
  • a pair of corrugated extension portions 17b are arranged so as to pass on one straight line with the electromagnetic field coupling portion 17a interposed therebetween.
  • the direction is preferably orthogonal to the extending direction of the carcass ply cord 7a, which is a conductive cord. The arrangement angle of the RFID tag may be changed.
  • the angle formed by the extending direction of the carcass ply cord 7a and the extending direction of the extending portion 17b is 10 to 90 degrees, more preferably 60 to 90 degrees, or the extending directions may be parallel to each other.
  • the shape of the extension portion 17b is corrugated.
  • the shape of the extension portion 17b is a wave shape, for example, a wave shape having a wobbling width of w and a pitch (wavelength) of p, and the folded portion of the wave shape, that is, the apex, is rounded, that is, the corner is rounded. It is also preferable. If it does so, the spring property of the 2nd antenna 17 can be improved.
  • the width w can be arbitrarily selected, but is preferably 0.5 mm to 20 mm, for example, and more preferably 1 mm to 15 mm.
  • the wave shape of the pitch p can be arbitrarily selected.
  • p is preferably 0.5 mm to 20 mm, and more preferably 5 mm to 20 mm.
  • the total length L17 of the second antenna 17 can be arbitrarily selected.
  • the total length L17 ′ of the second antenna 17 is preferably 1 ⁇ 4 or more of the wavelength of the communication frequency in order to secure a communication distance.
  • the communication frequency 2.45 GHz or UHF band (860 to 960 MHz) is mainly used.
  • the communication frequency is 920 MHz
  • the total length L17 of the second antenna 17 is 128 mm (2/5 wavelength).
  • Examples of the length of the entire length L17 of the second antenna 17 include 50 mm to 160 mm, and more preferably 70 mm to 135 mm.
  • the length L17 ′ when the second antenna 17 is straight can be arbitrarily selected, and examples thereof include 70 mm to 220 mm, and more preferably 100 mm to 190 mm.
  • the length of the electromagnetic field coupling portion 17a can be arbitrarily selected, but is large enough to accommodate the first antenna.
  • one side is preferably 3 mm to 13 mm.
  • the angle of the corner that forms the waveform can be arbitrarily selected. Preferably, it is 0 to 180 degrees.
  • the RFID chip 11, the first antenna 16, and the electromagnetic field coupling portion 17 a of the second antenna 17 are fixed by the second fixing member 14.
  • the material and configuration of the second fixing member 14 can be arbitrarily selected.
  • a material in which an adhesive is applied to the fixing surface side of a covering material made of synthetic resin such as nylon is suitably used as the second fixing member 14.
  • the second fixing member 14 fixes the RFID chip 11, the first antenna 16, and the electromagnetic field coupling portion 17 a of the second antenna 17 on the side opposite to the first fixing member 13. That is, the electromagnetic field coupling portion 17 a is disposed on the second fixing member 14.
  • the first antenna 16 and the RFID chip 11 are sandwiched between the first fixing member 13 and the second fixing member 14.
  • the position shift of the 1st antenna 16 and the 2nd antenna 17 can be prevented.
  • the RFID chip 11 and the first antenna 16 formed on the first fixing member 13 are covered with the second fixing member 14, bending stress is hardly applied. Therefore, the durability of the RFID tag 10 can be greatly improved. Even if the second antenna 17 is damaged, the connection portion between the RFID chip 11 and the first antenna 16 is hardly damaged. For this reason, the information stored in the RFID chip 11 can be confirmed without removing the RFID chip 11.
  • the RFID chip 11, the first antenna 16, and the electromagnetic field coupling portion 17 a of the second antenna 17 are connected to the first fixing member 13 from both the side opposite to the first fixing member 13 and the first fixing member 13 side. It is good also as a structure covered with the two fixing members 14. FIG. That is, the second fixing member 14 is used by being bent with a large area so that the member can be covered with the second fixing member 14, or two second fixing members 14 are prepared. You may use it in combination.
  • the loop closer to the electromagnetic field coupling portion 17a of the first antenna 16, that is, the outer loop, and the U-shaped electromagnetic field coupling portion 17a are substantially parallel and close to each other.
  • the distance d12 between the outer loop of the first antenna 16 and the U-shaped electromagnetic field coupling portion 17a is preferably 2 mm or less.
  • the total length L2 of the region of the second antenna 17 that is close to the first antenna 16 (d12 ⁇ 2 mm) is preferably not less than 1 ⁇ 2 of the outer peripheral length L1 of the first antenna 16.
  • the lower limit of the distance d12 can be arbitrarily selected.
  • the distance d12 is preferably 0 mm to 2 mm, more preferably 0 mm to 1 mm.
  • the dimension and length of the 2nd fixing member 14 can be selected arbitrarily.
  • the size may be larger than the first fixing member 13 and include at least the electromagnetic field coupling portion 17 a of the second antenna 17.
  • a part of the extension portion 17b may be disposed thereon.
  • the thickness 1 mm.
  • FIG. 5 shows a cross-sectional view of a portion where a tire RFID tag is arranged.
  • the carcass ply cord 7a is a conductive cord.
  • the distance D (ply-tag distance D) between the second antenna 17 and the surface of the carcass ply cord 7a shown in FIG. 5 can be arbitrarily selected. It is preferably in the range of 1 mm to 30 mm, more preferably in the range of 1.5 mm to 24 mm, and further preferably in the range of 2 mm to 15 mm.
  • the second antenna 17 and the carcass ply cord 7a can be sufficiently electromagnetically coupled. That is, the carcass ply cord 7a can function as the third antenna of the RFID tag 10.
  • D ⁇ 1 mm the carcass ply cord 7a and the antenna 12 are sufficiently electromagnetically coupled.
  • the antenna 12 particularly, the second antenna 17
  • the antenna 12 and the carcass ply cord 7a can be appropriately electromagnetically coupled without impairing durability. Therefore, the carcass ply cord 7a can function as the third antenna of the RFID tag 10.
  • Each of the carcass ply cords 7a serving as the third antenna is electromagnetically coupled to the adjacent carcass ply cord 7a. Therefore, communication with an external communication device such as a reader is possible not only on the tire side surface where the RFID tag 10 is embedded, but also on the tire upper surface and the side surface opposite to the side where the RFID tag 10 is embedded.
  • the allowable range of the ply-tag distance D may be further limited by the antenna overlap area ratio R.
  • the third fixing member 15 has an arbitrarily selected material and shape. For example, it is preferably made of a rubber sheet. Therefore, it is possible to reliably prevent the RFID tag 10 from being damaged.
  • the RFID tag 10 can be incorporated into the tire 1 after the RFID chip 11 and the antenna 12 are enclosed by the third fixing member 15. In this way, the RFID tag 10 can be easily incorporated into the tire 1 without fear of damage.
  • the ply-tag distance D the degree of overlap between the second antenna and the carcass ply cord 7a.
  • the strength of electromagnetic wave coupling between the carcass ply cord and an external antenna that is electromagnetically coupled is the distance D between the carcass ply cord and the external antenna that is electromagnetically coupled. It is said that the longer the length is, the longer the degree of overlap between the external antenna and the carcass ply cord is. That is, when the ply-tag distance D is long, the communication distance of the RFID tag can be increased by increasing the overlap degree K. However, as a result of investigations by the present inventors, it has been found that when the ply-tag distance D is short, the communication distance decreases rather when the overlapping degree is increased.
  • the degree of overlap between the external antenna and the carcass ply cord is the ratio of the overlap area A between the external antenna and the carcass ply cord to the area S of the external antenna (antenna overlap area ratio R). If the relationship between the ply-tag distance D and the antenna overlap area ratio R is appropriately set, the ply-tag distance D, the external antenna area S, and It has been found that since the allowable range of the overlapping area A between the external antenna and the carcass ply cord can be widened, the degree of freedom in designing the external antenna can be greatly increased.
  • an index of the degree of overlap between the second antenna and the carcass ply cord 7a is defined as an antenna overlap area ratio R.
  • FIG. 8 shows a state where the RFID tag 10 and the carcass ply cord 7a are seen through from above. The portion painted in black on the second antenna 17 is an overlapping portion between the second antenna and the carcass ply cord 7a.
  • the area S of the second antenna (and the area A of the overlapping portion) is the area (projected area) of the orthogonal projection of the second antenna onto the surface formed by the carcass ply cord.
  • a communication distance evaluation value P for evaluating whether or not the communication distance is a practical communication distance can be calculated.
  • the range of the communication distance evaluation value P is preferably 2 ⁇ P ⁇ 72, more preferably 2.5 ⁇ P ⁇ 62, and even more preferably 3 ⁇ P ⁇ 52. If necessary, it is also preferable that 15 ⁇ P ⁇ 50 or the like.
  • the range of both the ply-tag distance D and the antenna overlapping area ratio R is limited.
  • the range of the ply-tag distance D and the antenna overlap area ratio R for obtaining a communication distance that can be practically used can be widened. Therefore, the degree of freedom in designing the second antenna, such as the width w, the pitch p, or the shape of the extension portion 17b of the second antenna, can be greatly increased.
  • the antenna 12 of the RFID tag 10 is coupled to the first antenna 16 connected to the RFID chip 11 and the carcass ply cord 7a functioning as the antenna of the RFID tag 10 to the electromagnetic coupling.
  • the second antenna 17 is configured.
  • the second antenna 17 includes an electromagnetic field coupling portion 17a that electromagnetically couples to the first antenna 16 and a wave-shaped extension portion 17b that extends in a direction orthogonal to the extending direction of the carcass ply cord 7a. did. Therefore, a long communication distance can be secured and the durability of the RFID tag 10 can be improved.
  • the RFID chip 11, the first antenna 16, and the electromagnetic field coupling portion 17 a of the second antenna 17 are covered with the second fixing member 14. For this reason, the bending stress at the time of a deformation
  • the passive RFID tag 10 that performs wireless communication with a reader that reads tire data has been described.
  • the present invention is also applicable to an active RFID tag that transmits and receives data to and from a reader / writer.
  • the shape of the extension part 17b of the 2nd antenna 17 was made into the waveform, it is good also as a spiral shape. Thereby, since the spring property of the 2nd antenna 17 can further be improved, durability of the RFID tag 10 can be improved further.
  • the RFID tags shown in FIG. 2 and FIGS. 3A to 3C were used.
  • the 2nd fixing member 14 used what apply
  • the third fixing member 15 was a rubber sheet.
  • the communication frequency was 920 MHz, and the total length L17 of the second antenna 17 was 128 mm (2/5 wavelength).
  • the RFID chip 11 and the first antenna 16 are placed on the first fixing member 13 so that the RFID chip 11 and the first antenna 16 are located on the tire outer surface side and the first fixing member 13 is located on the tire inner surface side. Formed.
  • the mounting position of the RFID tag 10 is 30 mm above the bead core 6a, 10 mm below the upper end of the bead filler 6b, and on the outer side of the tire away from 4 mm from the carcass ply cord 7a disposed below.
  • D 4 mm.
  • the distance d12 between the outer loop of the first antenna 16 and the U-shaped electromagnetic field coupling portion 17a was set to 2 mm or less. However, the loop and the joint are not directly joined.
  • angles formed by the second antenna 17 of the RFID tag 10 according to the present invention and the carcass ply cord 7a as the third antenna are 0 °, 30 °, The angles were set to 60 ° and 90 ° (orthogonal) (Examples 1 to 4). The results of measuring the communication distance at these times are shown in Table 1 below.
  • Example 5 and Comparative Example 1 A conventional RFID tag 50 in which a communication distance of the RFID tag 10 according to a preferred example of the present invention shown in FIG. 6 and a RFID chip 51 and a helical antenna 52 are physically coupled as shown in FIG. Compared with the communication distance.
  • the angle formed between the extending direction of the antenna 52 of the conventional RFID tag 50 and a carcass ply cord (not shown) is 90 ° as in the RFID tag 10 according to the present invention.
  • the specifications of the conventional RFID tag 50 are shown in Table 2 below, and the comparison results are shown in Table 3.
  • the RFID tag 10 and the RFID tag 50 are sandwiched between rubber sheets having a thickness of 2 mm, and the distance between the carcass ply cord and the second antenna 17 and the distance between the carcass ply cord and the antenna 52 are as follows: It installed in the position used as 5 mm, and measured.
  • the rubber sheet a rubber containing 20 parts by weight of CB (carbon black) and 3 parts by weight of Si was used.
  • the communication distance is an index when the value of the conventional RFID tag 50 is 100.
  • the RFID tag 10 (Example 5) of the present invention can secure a communication distance about 10 times that of the conventional RFID tag 50 (Comparative Example 1).
  • the second antenna 17 is not physically coupled to the RFID chip 11. Therefore, the antenna length (full length) can be increased, and sufficient electromagnetic field coupling with the carcass ply cord 7a can be achieved.
  • the conventional RFID tag 50 cannot be made long because of its durability, so that sufficient electromagnetic field coupling with the carcass ply cord is not achieved.
  • the antenna 52 is formed in a spiral shape to increase the calculated antenna length, but it is considered that the effect is small.
  • Examples 6 to 31 and Comparative Examples 2 to 6 32 RFID tags shown in FIG. 3 were prepared.
  • Example 4 except for the features described below so that each RFID tag is radially lower than the bead filler end of the tire having a conductive carcass ply cord and radially outer than the bead end.
  • Each tire was mounted on the vehicle.
  • the ply-tag distance D when mounted is 1, 4, 5, 10, 15, 20, 25, or 30 mm, and the antenna overlap area ratio R is 0.29, 0.35, 0.6, or 0.64.
  • Table 4 for the combinations where the communication distance index is 100 or more, the example numbers are assigned from the left side to the right side and from top to bottom in the table. Comparative examples were similarly given comparative example numbers for those less than 100).
  • Table 5 is a table showing the communication distance evaluation value P of each RFID tag.
  • the communication distance is a distance from the tire surface where the tag can be read without any trouble by a reader (RFID tag reader manufactured by ATID).
  • the values in Table 4 are index values (communication distance index) when the measured communication distance is defined as a communication distance that can withstand practical use. It is preferable that the communication distance index is high.
  • the communication distance that can be practically used refers to a distance that can be read from the outside of the truck when the RFID tag is attached to the inner tire of the rear wheels (double tires) of the truck.
  • RFID tags with 2 ⁇ P ⁇ 72 all have a communication distance index of 100 or more, and RFID tags with 3 ⁇ P ⁇ 52 all have a communication distance index exceeding 105. Recognize. On the other hand, it can be seen that the RFID tag with P ⁇ 2 and the RFID tag with P ⁇ 72 are both shorter in communication distance than can be practically used. Thereby, it was confirmed that if the communication distance evaluation value P is 2 or more and less than 72, a communication distance that can withstand practical use can be secured.

Abstract

Provided is a tire having embedded therein an RFID tag comprising an RFID chip and an antenna, the tire with an embedded RFID tag is characterized in that: the antenna comprises a first antenna connected to the RFID chip, and a second antenna provided to the exterior of the first antenna and electromagnetically coupled to the first antenna; the RFID chip and the first antenna are fixed to a first fixing member; the RFID tag is disposed at a position which is outward, in the tire radial direction, from a carcass ply end of the tire; and the second antenna is electromagnetically coupled to a conductive carcass ply cord constituting the carcass ply.

Description

ＲＦＩＤタグ内蔵タイヤRFID tag built-in tire
　本発明は、ＲＦＩＤタグが内蔵されたタイヤに関する。
　本願は、２０１６年１月２５日に日本に出願された特願２０１６－０１１７８６号、及び、２０１６年１月２５日に日本に出願された特願２０１６－０１１７８７号に基づき優先権を主張し、その内容をここに援用する。 The present invention relates to a tire incorporating an RFID tag.
This application claims priority based on Japanese Patent Application No. 2016-011786 filed in Japan on January 25, 2016 and Japanese Patent Application No. 2016-011787 filed in Japan on January 25, 2016. The contents are incorporated here.
　従来、タイヤ内部のカーカスプライの自由端側の延長線上に、ＲＦＩＤ（ｒａｄｉｏ ｆｒｅｑｕｅｎｃｙ ｉｄｅｎｔｉｆｉｅｒ）チップを埋設するとともに、無線通信にて、ＲＦＩＤチップに記憶されたタイヤの情報を読み取る方法が行われている（例えば、特許文献１，２参照）。前記方法においては、ＲＦＩＤチップの両端から、タイヤの中心軸上に中心を持つ円の円周方向、すなわち、タイヤの回転方向に延長して、カーカスプライのコードと電磁界結合する、ダイポールアンテナが備えられている。前述の特許文献２の技術では、ＲＦＩＤチップとＲＦＩＤチップのアンテナピンに接続される外部アンテナ（ダイポールアンテナ）とを備えたＲＦＩＤタグがタイヤ内部に埋設されており、前記ＲＦＩＤタグと、外部アンテナと導電性を有するカーカスプライコードとは、電磁波結合している。 2. Description of the Related Art Conventionally, a method of embedding a radio frequency (RFID) chip on an extension line on the free end side of a carcass ply inside a tire and reading tire information stored in the RFID chip by wireless communication has been performed. (For example, refer to Patent Documents 1 and 2). In the above method, there is a dipole antenna that extends from both ends of the RFID chip in the circumferential direction of a circle having a center on the central axis of the tire, that is, in the rotation direction of the tire and is electromagnetically coupled to the carcass ply cord. Is provided. In the technique of Patent Document 2 described above, an RFID tag including an RFID chip and an external antenna (dipole antenna) connected to an antenna pin of the RFID chip is embedded in a tire, and the RFID tag, the external antenna, The conductive carcass ply cord is electromagnetically coupled.
　また、送受信機能及び記憶機能を備えた回路基板とアンテナコイルとを、筒状容器内に収納して一体化した、トランスポンダが知られている（例えば、特許文献３参照）。 Also, a transponder is known in which a circuit board having a transmission / reception function and a storage function and an antenna coil are integrated in a cylindrical container (see, for example, Patent Document 3).
特開２００８－２６５７５０号公報JP 2008-265750 A 特表２００５－５３５４９７号公報JP 2005-535497 A 特開２００６－５６４４３号公報JP 2006-56443 A
　特許文献１，２に記載の方法によれば、ダイポールアンテナとカーカスプライとが電磁界結合している。このため、十分な通信距離を確保することは可能である。しかしながら、ダイポールアンテナがビード部近傍に設けられていた。このことから、リム組時や突起乗り上げ時等のようにタイヤが大きく変形した時には、負荷がかかり、ＲＦＩＤチップとアンテナや、アンテナピンと外部アンテナ、との接合部が破損する可能性があった。そのため通信ができなくなり、その結果、ＲＦＩＤチップに記憶した情報が読み出せなくなってしまうといった問題点があった。 According to the methods described in Patent Documents 1 and 2, the dipole antenna and the carcass ply are electromagnetically coupled. For this reason, it is possible to ensure a sufficient communication distance. However, a dipole antenna has been provided in the vicinity of the bead portion. For this reason, when the tire is greatly deformed, such as when the rim is assembled or when the protrusion is mounted, a load is applied, and the joint between the RFID chip and the antenna or the antenna pin and the external antenna may be damaged. As a result, communication cannot be performed, and as a result, information stored in the RFID chip cannot be read.
　また、特許文献２では、外部アンテナとカーカスプライコードとの最適な位置関係が明確でないため、外部アンテナの位置によっては、十分な通信距離を確保することが困難であった。 Further, in Patent Document 2, since the optimal positional relationship between the external antenna and the carcass ply cord is not clear, it is difficult to secure a sufficient communication distance depending on the position of the external antenna.
　一方、特許文献３に記載のトランスポンダでは、ＲＦＩＤチップとアンテナとの接合部は破損しにくい構造である。しかしながら、通信距離が短いため、大型トラックなどのように複輪の場合には、内側のタイヤの情報を読み取るためには、特殊な読取装置（リーダ）が必要であった。
　また、特許文献３では、トランスポンダが配置された部位のタイヤ外表面に識別標識を設けて、トランスポンダの位置を確認可能としている。しかしながら、識別標識を設けた場合でも、識別標識の位置が見易いように車両を停止させなければならない等の問題があり、操作性が悪かった。 On the other hand, in the transponder described in Patent Document 3, the joint between the RFID chip and the antenna is not easily damaged. However, since the communication distance is short, a special reading device (reader) is required to read information on the inner tire in the case of a multi-wheel such as a large truck.
Moreover, in patent document 3, the identification mark is provided in the tire outer surface of the site | part in which the transponder is arrange | positioned, and the position of a transponder can be confirmed. However, even when the identification mark is provided, there is a problem that the vehicle must be stopped so that the position of the identification mark is easy to see, and the operability is poor.
　本発明は、従来の問題点に鑑みてなされたもので、十分な通信距離を確保できるとともに、耐久性にも優れたＲＦＩＤタグを内蔵したタイヤを提供することを目的とする。
　本発明の第一の態様は、以下のＲＦＩＤタグ内蔵タイヤである。
　すなわち、ＲＦＩＤチップとアンテナとを備えたＲＦＩＤタグが、内蔵されたタイヤであって、
　前記タイヤが導電性のカーカスプライコードを有するカーカスプライを有し、
　前記アンテナが、前記ＲＦＩＤチップに接続される第１のアンテナと、
　前記第１のアンテナの外部に設けられて前記第１のアンテナに電磁界結合される第２のアンテナとを備え、
　前記ＲＦＩＤチップと前記第１のアンテナとが、前記ＲＦＩＤタグの第１の固定部材に固定されており、
　前記ＲＦＩＤタグが、
　前記タイヤのカーカスプライ端から、タイヤ径方向の外側にある位置に、配置され、
　前記第２のアンテナが、
　前記カーカスプライを構成する導電性のカーカスプライコードと電磁界結合していることを特徴とするＲＦＩＤタグ内蔵タイヤである。
　本発明の第一の態様は、以下の特徴を有することも好ましい。これら特徴は互いに組み合わせて使用することも好ましい。
　前記第２のアンテナの延長方向と前記カーカスプライコードの延長方向とは直交しているが好ましい。
　前記第２のアンテナの前記第１のアンテナから所定距離以上離れた部分の形状が波型形状であることが好ましい。
　前記第２のアンテナの前記第１のアンテナから所定距離以内にある部分の長さが前記第１のアンテナの外周の長さの半分以上であることが好ましい。
　前記第１の固定部材とは反対側から、前記ＲＦＩＤチップと、前記第１のアンテナと、前記第２のアンテナの少なくとも前記第１のアンテナとの電磁界結合している部分とを覆う第２の固定部材を更に設けることが好ましい。 The present invention has been made in view of conventional problems, and an object of the present invention is to provide a tire with a built-in RFID tag that can secure a sufficient communication distance and is excellent in durability.
The first aspect of the present invention is the following RFID tag built-in tire.
That is, an RFID tag including an RFID chip and an antenna is a built-in tire,
The tire has a carcass ply having a conductive carcass ply cord;
A first antenna connected to the RFID chip;
A second antenna provided outside the first antenna and electromagnetically coupled to the first antenna;
The RFID chip and the first antenna are fixed to a first fixing member of the RFID tag;
The RFID tag is
From the carcass ply end of the tire, disposed at a position outside the tire radial direction,
The second antenna is
An RFID tag-embedded tire characterized by being electromagnetically coupled to a conductive carcass ply cord constituting the carcass ply.
The first aspect of the present invention preferably has the following features. These features are also preferably used in combination with each other.
The extension direction of the second antenna and the extension direction of the carcass ply cord are preferably orthogonal.
The shape of the portion of the second antenna that is away from the first antenna by a predetermined distance or more is preferably a wave shape.
It is preferable that the length of the portion of the second antenna that is within a predetermined distance from the first antenna is half or more of the outer circumference of the first antenna.
A second covering the RFID chip, the first antenna, and a portion of the second antenna that is electromagnetically coupled to at least the first antenna from the side opposite to the first fixing member. It is preferable to further provide a fixing member.
　本発明の第二の態様は、以下のＲＦＩＤタグ内蔵タイヤである。
　すなわち、ＲＦＩＤチップとアンテナとを備えたＲＦＩＤタグが内蔵されたタイヤであって、
　前記タイヤのカーカスプライが導電性のカーカスプライコードを有し、
　前記アンテナが、前記ＲＦＩＤチップに接続される第１のアンテナと、
　前記第１のアンテナの外部に設けられて前記第１のアンテナに電磁界結合される第２のアンテナとを備え、
　前記第２のアンテナと前記カーカスプライコード間の距離をＤ、前記第２のアンテナとカーカスプライコードとの重なり面積をＡ、前記第２のアンテナの面積をＳ、前記重なり面積Ａを前記第２のアンテナの面積Ｓで除した値をアンテナ重なり面積率Ｒ、前記距離Ｄを前記アンテナ重なり面積率Ｒで除した値を通信距離評価値Ｐとしたとき、前記通信距離評価値Ｐが２以上７２未満であることを特徴とするＲＦＩＤタグ内蔵タイヤである。
　本発明の第二の態様は、以下の特徴を有することも好ましい。これら特徴は互いに組み合わせて使用することも好ましい。
　前記Ｐが３以上５２未満であることが好ましい。
　前記第２のアンテナの延長方向と前記カーカスプライコードの延長方向とが直交していることが好ましい。
　前記第２のアンテナの形状が波型形状であることが好ましい。 The second aspect of the present invention is the following RFID tag built-in tire.
That is, a tire with a built-in RFID tag including an RFID chip and an antenna,
The carcass ply of the tire has a conductive carcass ply cord,
A first antenna connected to the RFID chip;
A second antenna provided outside the first antenna and electromagnetically coupled to the first antenna;
The distance between the second antenna and the carcass ply cord is D, the overlapping area between the second antenna and the carcass ply cord is A, the area of the second antenna is S, and the overlapping area A is the second When the value obtained by dividing the antenna area S by the antenna overlap area ratio R and the value obtained by dividing the distance D by the antenna overlap area ratio R are the communication distance evaluation value P, the communication distance evaluation value P is 2 or more and 72. It is an RFID tag built-in tire characterized by being less than.
The second aspect of the present invention preferably has the following features. These features are also preferably used in combination with each other.
The P is preferably 3 or more and less than 52.
It is preferable that the extending direction of the second antenna is orthogonal to the extending direction of the carcass ply cord.
It is preferable that the shape of the second antenna is a wave shape.
　なお、前記発明の第一と第二の態様は、特に問題が無い限り、互いの特徴や好ましい特徴を共有してもよい。 It should be noted that the first and second aspects of the invention may share each other's characteristics and preferable characteristics as long as there is no particular problem.
　本発明は、十分な通信距離を確保できるとともに、耐久性にも優れたＲＦＩＤタグを内蔵したタイヤを提供する。 The present invention provides a tire with a built-in RFID tag that can secure a sufficient communication distance and has excellent durability.
本発明のタイヤの好ましい例を示す、断面図である。It is sectional drawing which shows the preferable example of the tire of this invention. 本発明の、タイヤに含まれるＲＦＩＤタグの好ましい例を示す模式図である。It is a schematic diagram which shows the preferable example of the RFID tag contained in a tire of this invention. 第１のアンテナの好ましい例を示す、平面図である。It is a top view which shows the preferable example of a 1st antenna. 第２のアンテナの好ましい例を示す、平面図である。It is a top view which shows the preferable example of a 2nd antenna. 第１及び第２のアンテナの組み合わせの一部分を示す、平面図である。It is a top view which shows a part of combination of the 1st and 2nd antenna. 第１及び第２のアンテナの組み合わせ構造の例を示す、平面図である。It is a top view which shows the example of the combination structure of a 1st and 2nd antenna. ＲＦＩＤタグとカーカスプライとの関係の例を示す、断面図である。It is sectional drawing which shows the example of the relationship between a RFID tag and a carcass ply. アンテナの方向とカーカスプライとの関係の例を示す、断面図である。It is sectional drawing which shows the example of the relationship between the direction of an antenna, and a carcass ply. 従来のＲＦＩＤタグを示す図である。It is a figure which shows the conventional RFID tag. 通信距離評価値の算出方法を示す図である。It is a figure which shows the calculation method of a communication distance evaluation value.
　以下に本発明のＲＦＩＤタグ内蔵タイヤを実施するための好ましい例について、説明する。
　なお、以下の例は、発明の趣旨をより良く理解させるために具体的に説明するものであり、特に指定のない限り、本発明を限定するものではない。発明を逸脱しない範囲で、数や位置や大きさや数値などの変更や省略や追加をする事ができる。また説明を容易にするために、図に使用された寸法や比率が実際のものとは異なることがある。第一の態様と第二の態様の好ましい例や特徴を、問題の無い限り互いに組み合わせて使用しても良い。 A preferred example for implementing the RFID tag built-in tire of the present invention will be described below.
The following examples are specifically described for better understanding of the gist of the invention, and do not limit the present invention unless otherwise specified. Changes, omissions, and additions of numbers, positions, sizes, and numerical values can be made without departing from the invention. For ease of explanation, dimensions and ratios used in the drawings may be different from actual ones. The preferable examples and features of the first aspect and the second aspect may be used in combination as long as there is no problem.
＜第一の態様＞
　本発明の第一の態様を、具体例を挙げて説明すれば、図３Ａ～３Ｂ等に示すように、ＲＦＩＤチップ１１とアンテナ１２とを備えたＲＦＩＤタグ１０が内蔵されたタイヤにおいて、アンテナ１２を、ＲＦＩＤチップ１１に接続される第１のアンテナ１６と、第１のアンテナ１６の外部に設けられて第１のアンテナ１６に電磁界結合される第２のアンテナ１７とから構成する。ＲＦＩＤチップ１１と第１のアンテナ１６とを第１の固定部材１３に固定し、前記ＲＦＩＤタグ１０をタイヤのカーカスプライ端のタイヤ径方向外側に配置し、前記第２のアンテナ１７をカーカスプライを構成する導電性のカーカスプライコード７ａと電磁界結合する。前記タイヤのカーカスプライ端のタイヤ径方向外側とは、図１において、ビードコアとサイドウオール部が配置されている近傍と言い換えることもできる。
　第一の態様では、このように、アンテナを、カーカスプライコードと電磁界結合させたので、十分な通信距離を確保することができる。
　また、アンテナのカーカスプライコードと電磁界結合している部位である第２のアンテナを、アンテナのＲＦＩＤチップに接続される部位である第１のアンテナと電磁界結合させている。これらは直接結合していない。このことで、従来のような、タイヤが大きく変形した場合に破損し易い接合部をなくす構成とした。よって、ＲＦＩＤタグの耐久性が向上する。 <First aspect>
The first aspect of the present invention will be described with reference to specific examples. As shown in FIGS. 3A to 3B and the like, in the tire in which the RFID tag 10 including the RFID chip 11 and the antenna 12 is built, the antenna 12 Are composed of a first antenna 16 connected to the RFID chip 11 and a second antenna 17 provided outside the first antenna 16 and electromagnetically coupled to the first antenna 16. The RFID chip 11 and the first antenna 16 are fixed to the first fixing member 13, the RFID tag 10 is disposed on the outer side in the tire radial direction of the end of the carcass ply of the tire, and the second antenna 17 is attached to the carcass ply. It is electromagnetically coupled to the conductive carcass ply cord 7a. The outer side in the tire radial direction of the end of the carcass ply of the tire in FIG. 1 can also be referred to as the vicinity where the bead core and the side wall portion are arranged.
In the first aspect, since the antenna is electromagnetically coupled to the carcass ply cord as described above, a sufficient communication distance can be ensured.
Further, the second antenna, which is a part that is electromagnetically coupled to the carcass ply cord of the antenna, is electromagnetically coupled to the first antenna that is a part connected to the RFID chip of the antenna. They are not directly bonded. As a result, the conventional joint is configured to eliminate a joint that is easily damaged when the tire is greatly deformed. Therefore, durability of the RFID tag is improved.
　また、前記第２のアンテナの延長方向と前記カーカスプライコードの延長方向とを直交させたので、第２のアンテナとカーカスプライコードとを十分に電磁界結合させることができる。したがって、ＲＦＩＤタグの通信距離を更に伸ばすことができる。
　なお、「直交させる」とは、第２のアンテナの延長方向とカーカスプライコードの延長方向とのなす角度を、略９０°（９０°±１０°）の範囲とすることを指す。
　また、前記第２のアンテナは、その両端部からコ型の部位に至るまでの形状を、波型形状とした。よって、変形によるアンテナの破損を低減することができる。波型形状の部位の長さは任意に選択してよい。
　また、前記第２のアンテナの前記第１のアンテナから所定距離以内にある部分の長さを、前記第１のアンテナの外周の長さの半分以上とすることが好ましい。第一アンテナ外周を、コ型に第二アンテナで囲うことで、通信特性が良好になる。よって、第１のアンテナと第２のアンテナとを確実に電磁界結合させることができ、十分な通信距離を確保できる。
　また、前記第１の固定部材とは反対側から、前記ＲＦＩＤチップと、前記第１のアンテナと、前記第２のアンテナの少なくとも前記第１のアンテナとの電磁界結合している部分と、を覆う第２の固定部材を設けることも好ましい。その結果、ＲＦＩＤタグに作用する応力を緩和するようにでき、耐久性を更に向上させることができる。 In addition, since the extension direction of the second antenna and the extension direction of the carcass ply cord are orthogonal to each other, the second antenna and the carcass ply cord can be sufficiently electromagnetically coupled. Therefore, the communication distance of the RFID tag can be further increased.
Note that “perpendicular” means that the angle formed by the extension direction of the second antenna and the extension direction of the carcass ply cord is in a range of approximately 90 ° (90 ° ± 10 °).
The second antenna has a corrugated shape from both ends to the U-shaped portion. Therefore, damage to the antenna due to deformation can be reduced. The length of the corrugated portion may be arbitrarily selected.
In addition, it is preferable that the length of the portion of the second antenna that is within a predetermined distance from the first antenna is not less than half the length of the outer periphery of the first antenna. By surrounding the outer periphery of the first antenna with a second antenna in a U shape, the communication characteristics are improved. Therefore, the first antenna and the second antenna can be reliably electromagnetically coupled, and a sufficient communication distance can be ensured.
Further, from the side opposite to the first fixing member, the RFID chip, the first antenna, and the portion of the second antenna that is electromagnetically coupled to at least the first antenna, It is also preferable to provide a covering second fixing member. As a result, stress acting on the RFID tag can be relaxed, and durability can be further improved.
＜第二の態様＞
　
　本発明の第二の態様は、具体例を挙げて説明すれば、図３Ａ～３Ｂ及び図５に示すように、ＲＦＩＤチップ１１とアンテナ１２とを備えたＲＦＩＤタグ１０が内蔵されたタイヤにおいて、カーカスプライが導電性のカーカスプライコード７ａを有し、アンテナ１２を、ＲＦＩＤチップ１１に接続される第１のアンテナ１６と、第１のアンテナ１６の外部に設けられて第１のアンテナ１６に電磁波結合される第２のアンテナ１７とから構成する。これらとともに、第２のアンテナ１７とカーカスプライコード７ａ間の距離をＤ、第２のアンテナ１６とカーカスプライコード７ａとの重なり面積をＡ、第２のアンテナの面積をＳ、重なり面積Ａを第２のアンテナの面積Ｓで除した値をアンテナ重なり面積率Ｒ、距離Ｄをアンテナ重なり面積率Ｒで除した値を通信距離評価値Ｐとする。このとき、Ｐは２≦Ｐ＜７２である。 <Second aspect>

If the second aspect of the present invention is described with a specific example, as shown in FIGS. 3A to 3B and FIG. 5, in the tire in which the RFID tag 10 including the RFID chip 11 and the antenna 12 is incorporated, The carcass ply has a conductive carcass ply cord 7a, and the antenna 12 is provided to the first antenna 16 connected to the RFID chip 11 and to the first antenna 16 provided with electromagnetic waves. The second antenna 17 is coupled to the second antenna 17. Together with these, the distance between the second antenna 17 and the carcass ply cord 7a is D, the overlapping area of the second antenna 16 and the carcass ply cord 7a is A, the area of the second antenna is S, and the overlapping area A is the first The value obtained by dividing the antenna area S by the antenna overlap area ratio R and the distance D by the antenna overlap area ratio R are defined as the communication distance evaluation value P. At this time, P is 2 ≦ P <72.
　なお、第２のアンテナの面積Ｓ及び重なり面積Ａは、第２のアンテナのカーカスプライコードの作る面へ正射影の面積（投影面積）を指す。
　このように、カーカスプライコードと電磁波結合する第２のアンテナとカーカスプライコードとを、通信距離評価値Ｐが２＜Ｐ＜７２の範囲になるように電磁波結合させるとともに、アンテナのＲＦＩＤチップに接続される部位である第１のアンテナと第２のアンテナとを（機械的に結合させずに）電磁波結合させた。その結果、実用に耐えうる十分な通信距離を確保することができる。また、本発明のＲＦＩＤタグは、タイヤが大きく変形した場合に破損し易い接合部がないので、耐久性を大幅に向上させることができる。 Note that the area S and the overlapping area A of the second antenna indicate the area (projected area) of the orthogonal projection onto the surface formed by the carcass ply cord of the second antenna.
In this way, the second antenna and the carcass ply cord that are electromagnetically coupled to the carcass ply cord are electromagnetically coupled so that the communication distance evaluation value P is in the range of 2 <P <72 and connected to the RFID chip of the antenna. The first antenna and the second antenna, which are parts to be connected, were electromagnetically coupled (without mechanically coupling). As a result, a sufficient communication distance that can withstand practical use can be secured. Moreover, since the RFID tag of the present invention does not have a joint that is easily damaged when the tire is greatly deformed, the durability can be greatly improved.
　また、前記Ｐを３以上５２未満とすれば、実用に耐える通信距離を確実に得ることができる。
　また、前記第２のアンテナの延長方向と前記カーカスプライコードの延長方向とを直交させたので、第２のアンテナの変形を小さくすることができ、その結果、アンテナの耐久性が向上した。
　また、前記第２のアンテナの形状を波型形状としたので、タイヤの変形によるアンテナの破損を低減することができる。　 Moreover, if the P is 3 or more and less than 52, a communication distance that can be practically used can be obtained with certainty.
Further, since the extension direction of the second antenna and the extension direction of the carcass ply cord are orthogonal, the deformation of the second antenna can be reduced, and as a result, the durability of the antenna is improved.
In addition, since the second antenna has a corrugated shape, damage to the antenna due to deformation of the tire can be reduced.
　以下、本発明の第一と第二の態様の、好ましい例や特徴についてより詳細に説明する。
　図１は、本発明の好ましい例であるタイヤ１を示す断面図である。タイヤ１は略ドーナッツ型を有している。図１はタイヤ１をビード部の断面が示されるように、かつタイヤの中心軸を通るように切断した時の、左右対称の断面の一つを示す。２はトレッド部、３はベルト層、４はサイドウォール部、５はショルダー部、６はビード部、７はカーカスプライ、１０は本発明のＲＦＩＤタグを示す。
　トレッド部２は、タイヤ１が路面と接する部分であり、厚いゴム層から構成される。ゴム層の表面にはトレッドパターンが形成されている。
　ベルト層３は、コードをゴム部材で被覆したものである。タイヤ周方向の剛性を保つ「たが効果」を持たせるために、トレッド部２とカーカスプライ７との間に複数層配置される。
　サイドウォール部４は、トレッド部２とビード部６の間に設けられたゴム層である。
ショルダー部５は、トレッド部２と同じ部材で連続する、サイドウォール部４側に位置するゴム層である。
　ビード部６は、一対のビードコア６ａとビードフィラー６ｂとを備え、タイヤ１の中心を通るタイヤ中心軸に垂直な平面に対して、左右に対称に配置される。ホイールと組み合わされる部分である。
　ビードコア６ａは、スチールワイヤの束をリング状に形成したものをゴム部材で被覆したものである。ビードフィラー６ｂは、ビード部６に剛性を与えるために、サイドウォール部４のゴム層とビードコア６ａとカーカスプライ７との間に充填される、断面が三角形のゴム部材である。 Hereinafter, preferred examples and features of the first and second aspects of the present invention will be described in more detail.
FIG. 1 is a cross-sectional view showing a tire 1 which is a preferred example of the present invention. The tire 1 has a substantially donut shape. FIG. 1 shows one of the symmetric cross sections when the tire 1 is cut so that the cross section of the bead portion is shown and passes through the central axis of the tire. 2 is a tread portion, 3 is a belt layer, 4 is a sidewall portion, 5 is a shoulder portion, 6 is a bead portion, 7 is a carcass ply, and 10 is an RFID tag of the present invention.
The tread portion 2 is a portion where the tire 1 is in contact with the road surface, and is constituted by a thick rubber layer. A tread pattern is formed on the surface of the rubber layer.
The belt layer 3 is obtained by covering a cord with a rubber member. A plurality of layers are arranged between the tread portion 2 and the carcass ply 7 in order to have a “definite effect” that maintains rigidity in the tire circumferential direction.
The sidewall portion 4 is a rubber layer provided between the tread portion 2 and the bead portion 6.
The shoulder portion 5 is a rubber layer located on the side wall portion 4 side that is continuous with the same member as the tread portion 2.
The bead portion 6 includes a pair of bead cores 6 a and bead fillers 6 b, and is arranged symmetrically on the left and right with respect to a plane perpendicular to the tire central axis passing through the center of the tire 1. It is the part combined with the wheel.
The bead core 6a is a steel wire bundle formed in a ring shape and covered with a rubber member. The bead filler 6b is a rubber member having a triangular cross section that is filled between the rubber layer of the sidewall portion 4, the bead core 6a, and the carcass ply 7 in order to give the bead portion 6 rigidity.
　カーカスプライ７は、複数本の導電性のコード（以下、カーカスプライコードという）７ａと、カーカスプライコード７ａを被覆する被覆ゴム７ｂと、から成る。カーカスプライ７は、タイヤの骨格を成す部材であり、一対のビードコア６ａ間に配置され、かつビードコア６ａを跨ぐように配置される。
　カーカスプライ７の両端部は、それぞれ、ビードコア６ａの周りにタイヤ１の内側から外側に折り曲げられて、折り曲げ部７ｃを形成する。
　後述するように、カーカスプライコード７ａは、誘電体であるビードフィラー６ｂを構成するゴム部材、及び被覆ゴム７ｂを介して、ＲＦＩＤタグ１０のアンテナ１２と電磁界結合され、その結果、カーカスプライコード７ａは、ＲＦＩＤタグ１０のアンテナとして機能する。 The carcass ply 7 includes a plurality of conductive cords (hereinafter referred to as carcass ply cords) 7a and a covering rubber 7b that covers the carcass ply cord 7a. The carcass ply 7 is a member that forms a skeleton of the tire, is disposed between the pair of bead cores 6a, and is disposed so as to straddle the bead cores 6a.
Both ends of the carcass ply 7 are bent around the bead core 6a from the inside to the outside of the tire 1 to form a bent portion 7c.
As will be described later, the carcass ply cord 7a is electromagnetically coupled to the antenna 12 of the RFID tag 10 via the rubber member constituting the bead filler 6b, which is a dielectric, and the covering rubber 7b. 7 a functions as an antenna of the RFID tag 10.
　図において、カーカスプライコードは、トレッド部においてトレッドセンターラインに対して直角の角度で交差している例を示している。ただしこれのみに限定されなくても良い。なおカーカスプライが複数層設けられる場合、本発明では、一番外側の層のカーカスプライを説明していると理解してよい。
　図２は、サイドウォール部４に設けられたＲＦＩＤタグ１０を、タイヤの側面側から観察した状態を示す。図２ではドーナッツ形状のタイヤ側面の一部が示されている。図２の上部がトレッド部に近い側であり、下部がビードコアに近い側である。説明を容易にするために、サイドウォール部４のゴム層は省略されている。ＲＦＩＤタグ１０は、図２や図３Ａ～３Ｃに示すように、ＲＦＩＤチップ１１と、ＲＦＩＤチップ１１に接続されるアンテナ１２と、第１～第３の固定部材１３～１５とを備える。ＲＦＩＤタグ１０は、タイヤ１のサイドウォール部４の下、すなわち内側に装着されており、図外のリーダと通信する（図１参照）。
　ＲＦＩＤタグ１０の装着位置は、本発明の範囲内において、任意に選択できる。サイドウォール部４に設けられることが好ましいが、これに限定されない。例えば、本発明のＲＦＩＤタグは、タイヤの内側ショルダー領域や外側ショルダー領域のいずれにでも設けられて良い。ＲＦＩＤタグ１０の装着位置としては、例えば実施例で使用されたような、ビードコア６ａよりも３０ｍｍ上方であって、ビードフィラー６ｂの上端部から１０ｍｍ下方であって、かつ下に配置されるカーカスプライコード７ａから４ｍｍ離れたタイヤ外側での配置などが挙げられる。 In the figure, the carcass ply cord shows an example in which the tread portion intersects at a right angle with respect to the tread center line. However, the present invention is not limited to this. When a plurality of carcass plies are provided, it may be understood that the outermost carcass ply is described in the present invention.
FIG. 2 shows a state in which the RFID tag 10 provided on the sidewall portion 4 is observed from the side surface side of the tire. FIG. 2 shows a part of the side surface of the donut-shaped tire. The upper part of FIG. 2 is the side close to the tread part, and the lower part is the side close to the bead core. For ease of explanation, the rubber layer of the sidewall portion 4 is omitted. As shown in FIGS. 2 and 3A to 3C, the RFID tag 10 includes an RFID chip 11, an antenna 12 connected to the RFID chip 11, and first to third fixing members 13 to 15. The RFID tag 10 is attached under the sidewall portion 4 of the tire 1, that is, inside, and communicates with a reader (not shown) (see FIG. 1).
The mounting position of the RFID tag 10 can be arbitrarily selected within the scope of the present invention. Although it is preferable to be provided in the side wall part 4, it is not limited to this. For example, the RFID tag of the present invention may be provided in either the inner shoulder region or the outer shoulder region of a tire. The mounting position of the RFID tag 10 is, for example, a carcass ply disposed 30 mm above the bead core 6a, 10 mm below the upper end of the bead filler 6b, and below, as used in the embodiment. For example, an arrangement on the outer side of the tire 4 mm away from the cord 7a may be mentioned.
　アンテナ１２は、ＲＦＩＤチップ１１に接続される第１のアンテナ１６と、第１のアンテナ１６の外部に設けられる第２のアンテナ１７とを備える。第１のアンテナ１６と第２のアンテナ１７は直接接続していない。アンテナの材料は任意に選択できるが、金属(エッチングによって得られたアンテナやワイヤー等からなるアンテナ等)、導電性繊維、導電性ペーストなどが例として挙げられる。アンテナの直径は任意に選択でき、例えば、第２のアンテナの直径として０．１ｍｍ～５．０ｍｍが挙げられ、より好ましくは０．２ｍｍ～１．０ｍｍなどが挙げられる。　
　本例では、図３Ａに示すように、使用周波数の帯域幅を拡大する目的で、第１のアンテナ１６を、それぞれが別の大きさの矩形を有する、二重ループアンテナとしている。なおアンテナ１６や１７は図に示す形状のみに限定されない。内側の矩形のサイズは１辺が１ｍｍ～１０ｍｍであることが好ましく、２ｍｍ～７ｍｍであることがより好ましい。外側の矩形のサイズは、１辺が　２ｍｍ～１２ｍｍであることが好ましく、４ｍｍ～７ｍｍであることがより好ましい。矩形は長方形や正方形であってもよい。内側の矩形の長さと外側の矩形の長さの比も任意に選択できるが、例えば１：１～３などが挙げられる。
　ＲＦＩＤチップ１１と第１のアンテナ１６とは、ＰＥＴ（ポリエチレンテレフタラート）などの任意の材料で形成された、フィルム状の基板である、第１の固定部材１３上に形成されている。なお、フィルム状の基板の材料の他の例としては、ポリイミドなどが挙げられる。第１の固定部材はフィルム状に限定されず、　第２固定部材への直接形成や基板状の形状であっても良い。
　以下、図２及び図３Ａ～３Ｃの紙面表側をタイヤ外面側として、紙面の裏側をタイヤ内面側として、説明する。
　本例では、ＲＦＩＤチップ１１と第１のアンテナ１６がタイヤ外面側に、第１の固定部材１３がタイヤ内面側に位置するように、ＲＦＩＤチップ１１と第１のアンテナ１６とを第１の固定部材１３上に形成した。
　以下、図２及び図３の左右方向を、左右方向（横方向ともいう）と、上下方向を上下方向（縦方向ともいう）と述べ、説明する。左右方向はタイヤ１の円周方向で、上下方向はタイヤ１の半径方向である。
　本例では、第１の固定部材１３を、縦の長さがａ1＝６ｍｍ、横の長さがａ２＝７ｍｍ、厚さがｔ＝０．１ｍｍのフィルムとした。しかしながら、第１の固定部材１３の形状及び寸法長さについては、ＲＦＩＤチップ１１及び第１のアンテナ１６の大きさや形状により、適宜決定すればよい。一般的な例として、ａ１＝１～１５ｍｍ、ａ２＝１～１５ｍｍ、厚さ＝０．１～３ｍｍなどが挙げられる。ただしこれらには限定されない。 The antenna 12 includes a first antenna 16 connected to the RFID chip 11 and a second antenna 17 provided outside the first antenna 16. The first antenna 16 and the second antenna 17 are not directly connected. The material of the antenna can be arbitrarily selected, and examples thereof include metals (antennas obtained by etching, antennas made of wires, etc.), conductive fibers, conductive pastes, and the like. The diameter of the antenna can be arbitrarily selected. For example, the diameter of the second antenna is 0.1 mm to 5.0 mm, more preferably 0.2 mm to 1.0 mm.
In this example, as shown in FIG. 3A, the first antenna 16 is a double-loop antenna, each having a rectangle of a different size, for the purpose of expanding the bandwidth of the used frequency. The antennas 16 and 17 are not limited to the shape shown in the figure. The size of the inner rectangle is preferably 1 mm to 10 mm on one side, and more preferably 2 mm to 7 mm. The size of the outer rectangle is preferably 2 mm to 12 mm on one side, and more preferably 4 mm to 7 mm. The rectangle may be a rectangle or a square. The ratio of the length of the inner rectangle to the length of the outer rectangle can also be arbitrarily selected, and examples thereof include 1: 1 to 3.
The RFID chip 11 and the first antenna 16 are formed on a first fixing member 13 which is a film-like substrate made of an arbitrary material such as PET (polyethylene terephthalate). Another example of the material for the film-like substrate is polyimide. The first fixing member is not limited to a film shape, and may be formed directly on the second fixing member or a substrate shape.
In the following description, the front side of the paper surface of FIGS. 2 and 3A to 3C is the tire outer surface side, and the back side of the paper surface is the tire inner surface side.
In this example, the RFID chip 11 and the first antenna 16 are first fixed so that the RFID chip 11 and the first antenna 16 are positioned on the tire outer surface side, and the first fixing member 13 is positioned on the tire inner surface side. Formed on member 13.
Hereinafter, the left-right direction in FIGS. 2 and 3 will be described as the left-right direction (also referred to as a horizontal direction), and the up-down direction will be described as an up-down direction (also referred to as a vertical direction). The horizontal direction is the circumferential direction of the tire 1, and the vertical direction is the radial direction of the tire 1.
In this example, the first fixing member 13 is a film having a vertical length of a1 = 6 mm, a horizontal length of a2 = 7 mm, and a thickness of t = 0.1 mm. However, the shape and dimensional length of the first fixing member 13 may be appropriately determined depending on the size and shape of the RFID chip 11 and the first antenna 16. Common examples include a1 = 1-15 mm, a2 = 1-15 mm, and thickness = 0.1-3 mm. However, it is not limited to these.
　第２のアンテナ１７は、図３Ｂに示すように、コの字型（Ｕ字型、あるいは一辺がない四角型）の電磁界結合部１７ａと、前記コの字型の両端部から、左方向、及び右方向に延長する一対の延長部１７ｂとを備える。電磁界結合は、電磁波結合という事もできる。図では、一対の波型の延長部１７ｂが、電磁界結合部１７ａを挟んで、一つの直線上を通るように、配置されている。
　延長部１７ｂの延長方向については、特に限定はない。導電性のコードであるカーカスプライコード７ａの延長方向と直交する方向とすることが好ましい。ＲＦＩＤタグの配置の角度を変えても良い。例えば、カーカスプライコード７ａの延長方向と延長部１７ｂの延長方向とが形成する角度が１０～９０度、より好ましくは６０～９０度であり、あるいは、延長方向が互いに平行する方向としてもよい。
延長部１７ｂの形状は波型である。延長部１７ｂの形状を波型、例えば振れ幅がｗ、ピッチ（波長）がｐの波型、とするとともに、波型の折り返し部、すなわち頂点、をＲ付け、すなわち角に丸味付け、をすることも好ましい。そうすれば、第２のアンテナ１７のバネ性を高めることができる。従って、第２のアンテナ１７の破断を低減することができ、ＲＦＩＤタグ１０の耐久性を一層向上させることができる。幅ｗは任意に選択できるが、例えば０．５ｍｍ　～２０ｍｍが好ましく、１ｍｍ～１５ｍｍがより好ましい。ピッチｐの波型も任意に選択できるが、例えばｐが０．５ｍｍ～２０ｍｍが好ましく、５ｍｍ～２０ｍｍがより好ましい。 As shown in FIG. 3B, the second antenna 17 has a U-shaped (U-shaped or square shape with no side) electromagnetic field coupling portion 17a and a left-hand direction from both ends of the U-shaped. And a pair of extensions 17b extending rightward. Electromagnetic coupling can also be called electromagnetic coupling. In the figure, a pair of corrugated extension portions 17b are arranged so as to pass on one straight line with the electromagnetic field coupling portion 17a interposed therebetween.
There is no limitation in particular about the extension direction of the extension part 17b. The direction is preferably orthogonal to the extending direction of the carcass ply cord 7a, which is a conductive cord. The arrangement angle of the RFID tag may be changed. For example, the angle formed by the extending direction of the carcass ply cord 7a and the extending direction of the extending portion 17b is 10 to 90 degrees, more preferably 60 to 90 degrees, or the extending directions may be parallel to each other.
The shape of the extension portion 17b is corrugated. The shape of the extension portion 17b is a wave shape, for example, a wave shape having a wobbling width of w and a pitch (wavelength) of p, and the folded portion of the wave shape, that is, the apex, is rounded, that is, the corner is rounded. It is also preferable. If it does so, the spring property of the 2nd antenna 17 can be improved. Therefore, the breakage of the second antenna 17 can be reduced, and the durability of the RFID tag 10 can be further improved. The width w can be arbitrarily selected, but is preferably 0.5 mm to 20 mm, for example, and more preferably 1 mm to 15 mm. The wave shape of the pitch p can be arbitrarily selected. For example, p is preferably 0.5 mm to 20 mm, and more preferably 5 mm to 20 mm.
　第２のアンテナ１７の全長Ｌ１７は、任意に選択できる。第２のアンテナ１７の全長Ｌ１７’としては、通信周波数の波長の１／４以上にすることが、通信距離を確保する上で好ましい。通信周波数としては、２．４５ＧＨｚやＵＨＦ帯（８６０～９６０ＭＨｚ）が主に用いられる。本例では、通信周波数を９２０ＭＨｚとし、第２のアンテナ１７の全長Ｌ１７を１２８ｍｍ（２／５波長）とした。第２のアンテナ１７の全長Ｌ１７の長さの例としては、５０ｍｍ～　１６０ｍｍが挙げられ、７０ｍｍ～１３５ｍｍがより好ましい。なお第２のアンテナ１７をまっすぐにした時の長さＬ１７’も任意に選択でき、例としては、７０ｍｍ～２２０ｍｍが挙げられ、１００ｍｍ～１９０ｍｍがより好ましい。
　電磁界結合部１７ａの長さは任意に選択できるが、第１のアンテナが中に納まる大きさである。例えば１辺が３ｍｍ～１３ｍｍであることが好ましい。波型を作る角部の角度は任意で選択できる。好ましくは０～１８０度である。 The total length L17 of the second antenna 17 can be arbitrarily selected. The total length L17 ′ of the second antenna 17 is preferably ¼ or more of the wavelength of the communication frequency in order to secure a communication distance. As the communication frequency, 2.45 GHz or UHF band (860 to 960 MHz) is mainly used. In this example, the communication frequency is 920 MHz, and the total length L17 of the second antenna 17 is 128 mm (2/5 wavelength). Examples of the length of the entire length L17 of the second antenna 17 include 50 mm to 160 mm, and more preferably 70 mm to 135 mm. Note that the length L17 ′ when the second antenna 17 is straight can be arbitrarily selected, and examples thereof include 70 mm to 220 mm, and more preferably 100 mm to 190 mm.
The length of the electromagnetic field coupling portion 17a can be arbitrarily selected, but is large enough to accommodate the first antenna. For example, one side is preferably 3 mm to 13 mm. The angle of the corner that forms the waveform can be arbitrarily selected. Preferably, it is 0 to 180 degrees.
　また、本例では、図３Ｃに示すように、ＲＦＩＤチップ１１と、第１のアンテナ１６と、第２のアンテナ１７の電磁界結合部１７ａと、を第２の固定部材１４により、固定する。第２の固定部材１４の材料や構成は任に選択できる。例えば、ナイロンなどの合成樹脂から成る被覆材の固定面側に接着剤を塗布したものが、第２の固定部材１４として好適に用いられる。
　第２の固定部材１４は、ＲＦＩＤチップ１１と、第１のアンテナ１６と、第２のアンテナ１７の電磁界結合部１７ａとを、第１の固定部材１３とは反対側にて固定する。すなわち、電磁界結合部１７ａは、第２の固定部材１４上に配置される。第１のアンテナ１６とＲＦＩＤチップ１１は、第１の固定部材１３と第２の固定部材１４により、挟み込まれる。これにより、第１のアンテナ１６と第２のアンテナ１７との位置ズレを防止することができる。加えて、第１の固定部材１３上に形成されたＲＦＩＤチップ１１と第１のアンテナ１６とが、第２の固定部材１４により被覆されるので、曲げ応力がかかりにくくなる。
　したがって、ＲＦＩＤタグ１０の耐久性を大幅に向上させることができる。また、仮に、第２のアンテナ１７が破損した場合でも、ＲＦＩＤチップ１１と第１のアンテナ１６との接続部までが破損することは殆どない。このため、ＲＦＩＤチップ１１を取出すことなく、ＲＦＩＤチップ１１に記憶された情報を確認することができる。
　なお、ＲＦＩＤチップ１１と第１のアンテナ１６と第２のアンテナ１７の電磁界結合部１７ａとを、第１の固定部材１３とは反対側、及び第１の固定部材１３側の両方から、第２の固定部材１４により覆う構成としてもよい。すなわち前記部材を第２の固定部材１４により覆うことができるように、第２の固定部材１４を面積を大きくして折り曲げて使用するか、あるいは２枚の第２の固定部材１４を用意して組み合わせて使用しても良い。 In this example, as shown in FIG. 3C, the RFID chip 11, the first antenna 16, and the electromagnetic field coupling portion 17 a of the second antenna 17 are fixed by the second fixing member 14. The material and configuration of the second fixing member 14 can be arbitrarily selected. For example, a material in which an adhesive is applied to the fixing surface side of a covering material made of synthetic resin such as nylon is suitably used as the second fixing member 14.
The second fixing member 14 fixes the RFID chip 11, the first antenna 16, and the electromagnetic field coupling portion 17 a of the second antenna 17 on the side opposite to the first fixing member 13. That is, the electromagnetic field coupling portion 17 a is disposed on the second fixing member 14. The first antenna 16 and the RFID chip 11 are sandwiched between the first fixing member 13 and the second fixing member 14. Thereby, the position shift of the 1st antenna 16 and the 2nd antenna 17 can be prevented. In addition, since the RFID chip 11 and the first antenna 16 formed on the first fixing member 13 are covered with the second fixing member 14, bending stress is hardly applied.
Therefore, the durability of the RFID tag 10 can be greatly improved. Even if the second antenna 17 is damaged, the connection portion between the RFID chip 11 and the first antenna 16 is hardly damaged. For this reason, the information stored in the RFID chip 11 can be confirmed without removing the RFID chip 11.
The RFID chip 11, the first antenna 16, and the electromagnetic field coupling portion 17 a of the second antenna 17 are connected to the first fixing member 13 from both the side opposite to the first fixing member 13 and the first fixing member 13 side. It is good also as a structure covered with the two fixing members 14. FIG. That is, the second fixing member 14 is used by being bent with a large area so that the member can be covered with the second fixing member 14, or two second fixing members 14 are prepared. You may use it in combination.
　図４に示すように、第１のアンテナ１６の電磁界結合部１７ａに近い方のループ、すなわち外側のループと、コの字型の電磁界結合部１７ａとは、略平行でかつ近接していることが好ましい。
　具体的には、第１のアンテナ１６の外側のループとコの字型の電磁界結合部１７ａとの距離ｄ１２を、２ｍｍ以下とすることが好ましい。また第２のアンテナ１７の第１のアンテナ１６に近接（ｄ１２≦２ｍｍ）している領域の全長Ｌ２を、第１のアンテナ１６の外周の長さＬ１の１／２以上とすることが好ましい。これにより、第１のアンテナ１６と第２のアンテナ１７とを確実に電磁界結合させることができる。距離ｄ１２の下限は任意に選択できる。距離ｄ１２は０ｍｍ～２ｍｍが好ましく、０ｍｍ～１ｍｍがより好ましい。　
　なお、第２の固定部材１４の寸法及び長さは任意に選択できる。例えば、第１の固定部材１３よりも大きく、かつ、少なくとも第２のアンテナ１７の電磁界結合部１７ａを含む大きさであればよい。延長部１７ｂの一部をその上に配置しても良い。本例では、第２の固定部材１４の縦の長さをｂ１＝１０ｍｍ、横の長さをｂ２＝１０ｍｍ、厚さをＴ＝１ｍｍとした。ただしこのサイズのみに限定されない。 As shown in FIG. 4, the loop closer to the electromagnetic field coupling portion 17a of the first antenna 16, that is, the outer loop, and the U-shaped electromagnetic field coupling portion 17a are substantially parallel and close to each other. Preferably it is.
Specifically, the distance d12 between the outer loop of the first antenna 16 and the U-shaped electromagnetic field coupling portion 17a is preferably 2 mm or less. The total length L2 of the region of the second antenna 17 that is close to the first antenna 16 (d12 ≦ 2 mm) is preferably not less than ½ of the outer peripheral length L1 of the first antenna 16. Thereby, the first antenna 16 and the second antenna 17 can be reliably electromagnetically coupled. The lower limit of the distance d12 can be arbitrarily selected. The distance d12 is preferably 0 mm to 2 mm, more preferably 0 mm to 1 mm.
In addition, the dimension and length of the 2nd fixing member 14 can be selected arbitrarily. For example, the size may be larger than the first fixing member 13 and include at least the electromagnetic field coupling portion 17 a of the second antenna 17. A part of the extension portion 17b may be disposed thereon. In this example, the vertical length of the second fixing member 14 is b1 = 10 mm, the horizontal length is b2 = 10 mm, and the thickness is T = 1 mm. However, it is not limited only to this size.
　ところで、カーカスプライコード７ａの径を１ｍｍ、間隔を１ｍｍとした場合、第２のアンテナ１７は、約６０本のカーカスプライコード７ａと交差していることになる。
　図５に、タイヤのＲＦＩＤタグが配置された部分の断面図を示す。カーカスプライコード７ａは導電性のコードである。図５に示す、第２のアンテナ１７とカーカスプライコード７ａの表面との距離Ｄ（プライ－タグ距離Ｄ）は任意に選択できる。１ｍｍ～３０ｍｍの範囲である事が好ましく、１．５ｍｍ～２４ｍｍの範囲である事がより好ましく、２ｍｍ～１５ｍｍの範囲とすることがさらに好ましい。この場合、第２のアンテナ１７とカーカスプライコード７ａとを十分に電磁界結合させることができる。すなわち、カーカスプライコード７ａをＲＦＩＤタグ１０の第３のアンテナとして機能させることができる。
　Ｄ＜１ｍｍである場合には、カーカスプライコード７ａとアンテナ１２とは十分に電磁界結合する。ただし、アンテナ１２とカーカスプライコード７ａとの距離が近すぎるため、タイヤが大きく変形した場合に、アンテナ１２（特に、第２のアンテナ１７）が破損してしまう恐れがある。一方、Ｄ＞３０ｍｍである場合には、カーカスプライコード７ａとアンテナ１２との電磁界結合が不十分である場合がある。このため、通信距離が短くなってしまう可能性がある。
　後述する実施例に示す例では、Ｄ＝４ｍｍとした。なおＤを上記の範囲とすれば、耐久性を損なうことなく、アンテナ１２とカーカスプライコード７ａとを適正に電磁界結合できる。よって、カーカスプライコード７ａをＲＦＩＤタグ１０の第３のアンテナとして機能させることができる。
　また、第３のアンテナであるカーカスプライコード７ａは、それぞれが、隣接するカーカスプライコード７ａと電磁界結合している。よって、ＲＦＩＤタグ１０が埋設されたタイヤ側面のみならず、タイヤ上面やＲＦＩＤタグ１０が埋設された側とは反対側の側面においても、読み取り機等の外部通信装置との通信が可能となる。 By the way, when the diameter of the carcass ply cord 7a is 1 mm and the interval is 1 mm, the second antenna 17 intersects with about 60 carcass ply cords 7a.
FIG. 5 shows a cross-sectional view of a portion where a tire RFID tag is arranged. The carcass ply cord 7a is a conductive cord. The distance D (ply-tag distance D) between the second antenna 17 and the surface of the carcass ply cord 7a shown in FIG. 5 can be arbitrarily selected. It is preferably in the range of 1 mm to 30 mm, more preferably in the range of 1.5 mm to 24 mm, and further preferably in the range of 2 mm to 15 mm. In this case, the second antenna 17 and the carcass ply cord 7a can be sufficiently electromagnetically coupled. That is, the carcass ply cord 7a can function as the third antenna of the RFID tag 10.
When D <1 mm, the carcass ply cord 7a and the antenna 12 are sufficiently electromagnetically coupled. However, since the distance between the antenna 12 and the carcass ply cord 7a is too short, the antenna 12 (particularly, the second antenna 17) may be damaged when the tire is greatly deformed. On the other hand, when D> 30 mm, the electromagnetic coupling between the carcass ply cord 7a and the antenna 12 may be insufficient. For this reason, the communication distance may be shortened.
In the example shown in the examples described later, D = 4 mm. If D is in the above range, the antenna 12 and the carcass ply cord 7a can be appropriately electromagnetically coupled without impairing durability. Therefore, the carcass ply cord 7a can function as the third antenna of the RFID tag 10.
Each of the carcass ply cords 7a serving as the third antenna is electromagnetically coupled to the adjacent carcass ply cord 7a. Therefore, communication with an external communication device such as a reader is possible not only on the tire side surface where the RFID tag 10 is embedded, but also on the tire upper surface and the side surface opposite to the side where the RFID tag 10 is embedded.
　なお、後述するように、プライ－タグ距離Ｄの許容範囲は、アンテナ重なり面積率Ｒにより更に限定しても良い。 As will be described later, the allowable range of the ply-tag distance D may be further limited by the antenna overlap area ratio R.
　更に、図２及び図５に示す例では、ＲＦＩＤチップ１１とアンテナ１２（第１のアンテナ１６と第２のアンテナ１７）との組み合わせを、第３の固定部材１５に内包している。第３の固定部材１５は任意に選択される材料と形状を有する。例えばゴム製のシートから成ることが好ましい。よって、ＲＦＩＤタグ１０の破損を確実に防止できる。また、ＲＦＩＤチップ１１とアンテナ１２とを第３の固定部材１５で内包した後に、ＲＦＩＤタグ１０をタイヤ１に組み込むことができる。このようにすれば、ＲＦＩＤタグ１０を容易にかつ破損のおそれなく、タイヤ１に組み込むことができる。 Further, in the example shown in FIGS. 2 and 5, a combination of the RFID chip 11 and the antenna 12 (the first antenna 16 and the second antenna 17) is included in the third fixing member 15. The third fixing member 15 has an arbitrarily selected material and shape. For example, it is preferably made of a rubber sheet. Therefore, it is possible to reliably prevent the RFID tag 10 from being damaged. In addition, the RFID tag 10 can be incorporated into the tire 1 after the RFID chip 11 and the antenna 12 are enclosed by the third fixing member 15. In this way, the RFID tag 10 can be easily incorporated into the tire 1 without fear of damage.
　実用に耐えうる通信距離を確保するためには、プライ－タグ距離Ｄと第２のアンテナとカーカスプライコード７ａとの重なり度合いを考慮する事が好ましい。 In order to ensure a practical communication distance, it is preferable to consider the ply-tag distance D, the degree of overlap between the second antenna and the carcass ply cord 7a.
　一般に、導電性を有するカーカスプライコードをＲＦＩＤタグのアンテナとして利用する場合、カーカスプライコードと電磁波結合する外部アンテナとの電磁波結合の強さは、カーカスプライコードと電磁波結合する外部アンテナとの距離Ｄが短く、かつ、外部アンテナとカーカスプライコードとの重なり度合いが大きいほど長くなるといわれている。
　すなわち、プライ－タグ距離Ｄが長い場合には、重なり度合いＫを大きくすればＲＦＩＤタグの通信距離を長くすることができる。
　しかしながら、本発明者らが検討したところ、プライ－タグ距離Ｄが短い場合には、重なり度合いを大きくすると、通信距離は、かえって低下することがわかった。
　本発明者らは、鋭意検討の結果、外部アンテナとカーカスプライコードとの重なり度合いは、外部アンテナの面積Ｓに対する外部アンテナとカーカスプライコードとの重なり面積Ａの割合（アンテナ重なり面積率Ｒ）で表せること、及び、プライ－タグ距離Ｄとアンテナ重なり面積率Ｒとの関係を適切に設定してやれば、実用に耐えうる通信距離を得るためのプライ－タグ距離Ｄ、外部アンテナの面積Ｓ、及び、外部アンテナとカーカスプライコードとの重なり面積Ａの許容範囲を広くできるので、外部アンテナの設計の自由度を大幅に広げることができることを見出したのである。 In general, when a conductive carcass ply cord is used as an antenna of an RFID tag, the strength of electromagnetic wave coupling between the carcass ply cord and an external antenna that is electromagnetically coupled is the distance D between the carcass ply cord and the external antenna that is electromagnetically coupled. It is said that the longer the length is, the longer the degree of overlap between the external antenna and the carcass ply cord is.
That is, when the ply-tag distance D is long, the communication distance of the RFID tag can be increased by increasing the overlap degree K.
However, as a result of investigations by the present inventors, it has been found that when the ply-tag distance D is short, the communication distance decreases rather when the overlapping degree is increased.
As a result of intensive studies, the present inventors have determined that the degree of overlap between the external antenna and the carcass ply cord is the ratio of the overlap area A between the external antenna and the carcass ply cord to the area S of the external antenna (antenna overlap area ratio R). If the relationship between the ply-tag distance D and the antenna overlap area ratio R is appropriately set, the ply-tag distance D, the external antenna area S, and It has been found that since the allowable range of the overlapping area A between the external antenna and the carcass ply cord can be widened, the degree of freedom in designing the external antenna can be greatly increased.
　ここで、第２のアンテナとカーカスプライコード７ａとの重なり度合いの指標をアンテナ重なり面積率Ｒとする。アンテナ重なり面積率Ｒは、第２のアンテナ１７とカーカスプライコード７ａとの重なり面積をＡ（ｍｍ２）、第２のアンテナ１７の面積をＳ（ｍｍ２）とすると、Ｒ＝Ａ／Ｓで表せる。
　図８にＲＦＩＤタグ１０とカーカスプライコード７ａを、上から透視した様子を示す。第２のアンテナ１７の黒く塗った部分が、第２のアンテナとカーカスプライコード７ａとの重なり部である。第２のアンテナの面積Ｓ（及び重なり部の面積Ａ）は、第２のアンテナの、カーカスプライコードの作る面への正射影の面積（投影面積）である。
　この重なり面積Ａと、プライ－タグ距離Ｄとを用いて、通信距離が実用に耐えうる通信距離であるか否かを評価するための通信距離評価値Ｐを算出する。
　通信距離評価値Ｐは、Ｐ＝Ｄ／Ｒにより算出される。
　通信距離評価値Ｐの範囲としては、２≦Ｐ＜７２とすることが好ましく、２．５≦Ｐ＜６２とすることがより好ましく、３≦Ｐ＜５２とすれば、更に好ましい。必要に応じて、１５≦Ｐ＜５０などであることも好ましい。
　このように、通信距離評価値Ｐを用いて、実用に耐えうる通信距離が確保できるか否かを判定すれば、プライ－タグ距離Ｄとアンテナ重なり面積率Ｒの両方の範囲を限定する場合に比較して、実用に耐えうる通信距離を得るためのプライ－タグ距離Ｄ及びアンテナ重なり面積率Ｒの範囲を広くできる。よって、第２のアンテナの延長部１７ｂの幅ｗやピッチｐ、あるいは、形状など、第２のアンテナの設計の自由度を大幅に広げることができる。 Here, an index of the degree of overlap between the second antenna and the carcass ply cord 7a is defined as an antenna overlap area ratio R. The antenna overlapping area ratio R is R = A / S, where A (mm 2 ) is the overlapping area of the second antenna 17 and the carcass ply cord 7a, and S (mm 2 ) is the area of the second antenna 17. I can express.
FIG. 8 shows a state where the RFID tag 10 and the carcass ply cord 7a are seen through from above. The portion painted in black on the second antenna 17 is an overlapping portion between the second antenna and the carcass ply cord 7a. The area S of the second antenna (and the area A of the overlapping portion) is the area (projected area) of the orthogonal projection of the second antenna onto the surface formed by the carcass ply cord.
Using this overlap area A and the ply-tag distance D, a communication distance evaluation value P for evaluating whether or not the communication distance is a practical communication distance can be calculated.
The communication distance evaluation value P is calculated by P = D / R.
The range of the communication distance evaluation value P is preferably 2 ≦ P <72, more preferably 2.5 ≦ P <62, and even more preferably 3 ≦ P <52. If necessary, it is also preferable that 15 ≦ P <50 or the like.
As described above, when it is determined whether or not a communication distance that can be practically used can be secured by using the communication distance evaluation value P, the range of both the ply-tag distance D and the antenna overlapping area ratio R is limited. In comparison, the range of the ply-tag distance D and the antenna overlap area ratio R for obtaining a communication distance that can be practically used can be widened. Therefore, the degree of freedom in designing the second antenna, such as the width w, the pitch p, or the shape of the extension portion 17b of the second antenna, can be greatly increased.
　以上のように、本発明の好ましい例では、ＲＦＩＤタグ１０のアンテナ１２を、ＲＦＩＤチップ１１と接続される第１のアンテナ１６と、ＲＦＩＤタグ１０のアンテナとして機能するカーカスプライコード７ａと電磁界結合する第２のアンテナ１７とから構成した。また前記構成とともに、第２のアンテナ１７を、第１のアンテナ１６と電磁界結合する電磁界結合部１７ａとカーカスプライコード７ａの延長方向に直交する方向に延長する波型の延長部１７ｂから構成した。従って、長い通信距離を確保できるとともに、ＲＦＩＤタグ１０の耐久性を向上させることができる。
　また、ＲＦＩＤチップ１１と第１のアンテナ１６と第２のアンテナ１７の電磁界結合部１７ａとを、第２の固定部材１４により被覆した。このため、タイヤの変形時における曲げ応力を緩和するようにでき、ＲＦＩＤタグ１０の耐久性を大幅に向上させることができる。 As described above, in the preferred example of the present invention, the antenna 12 of the RFID tag 10 is coupled to the first antenna 16 connected to the RFID chip 11 and the carcass ply cord 7a functioning as the antenna of the RFID tag 10 to the electromagnetic coupling. The second antenna 17 is configured. In addition to the above configuration, the second antenna 17 includes an electromagnetic field coupling portion 17a that electromagnetically couples to the first antenna 16 and a wave-shaped extension portion 17b that extends in a direction orthogonal to the extending direction of the carcass ply cord 7a. did. Therefore, a long communication distance can be secured and the durability of the RFID tag 10 can be improved.
Further, the RFID chip 11, the first antenna 16, and the electromagnetic field coupling portion 17 a of the second antenna 17 are covered with the second fixing member 14. For this reason, the bending stress at the time of a deformation | transformation of a tire can be relieved, and durability of the RFID tag 10 can be improved significantly.
　なお、前記実施の形態では、タイヤのデータを読みとるリーダとの間で無線通信するパッシブ型のＲＦＩＤタグ１０について説明した。しかしながら、本発明は、リーダ／ライタとの間でデータの送受信を行う、アクティブ型のＲＦＩＤタグにも適用可能である。
　また、前記実施の形態では、第２のアンテナ１７の延長部１７ｂの形状を波型としたが、螺旋状の形状としてもよい。これにより、第２のアンテナ１７のバネ性を更に高めることができるので、ＲＦＩＤタグ１０の耐久性を一層向上させることができる。 In the above-described embodiment, the passive RFID tag 10 that performs wireless communication with a reader that reads tire data has been described. However, the present invention is also applicable to an active RFID tag that transmits and receives data to and from a reader / writer.
Moreover, in the said embodiment, although the shape of the extension part 17b of the 2nd antenna 17 was made into the waveform, it is good also as a spiral shape. Thereby, since the spring property of the 2nd antenna 17 can further be improved, durability of the RFID tag 10 can be improved further.
［実施例］
　実施例１～４
　図２や図３Ａ～３Ｃに示すＲＦＩＤタグを用いた。
　第１の固定部材１３を、縦の長さがａ1＝６ｍｍ、横の長さがａ２＝７ｍｍ、厚さがｔ＝０．１ｍｍの、ＰＥＴフィルムとした。第２の固定部材１４の縦の長さをｂ１＝１０ｍｍ、横の長さをｂ２＝１０ｍｍ、厚さをＴ＝１ｍｍとした。第２の固定部材１４は、ナイロンから成る被覆材の固定面側に接着剤を塗布したものを使用した。第３の固定部材１５をゴム製のシートとした。　通信周波数を９２０ＭＨｚとし、第２のアンテナ１７の全長Ｌ１７を１２８ｍｍ（２／５波長）とした。ｗ：２．１ｍｍ、ｐ：７．５ｍｍとした。ＲＦＩＤチップ１１と第１のアンテナ１６がタイヤ外面側に、第１の固定部材１３がタイヤ内面側に位置するように、ＲＦＩＤチップ１１と第１のアンテナ１６とを、第１の固定部材１３上に形成した。
　ＲＦＩＤタグ１０の装着位置としては、ビードコア６ａよりも３０ｍｍ上方であって、ビードフィラー６ｂの上端部から１０ｍｍ下方であって、かつ下に配置されるカーカスプライコード７ａから４ｍｍから離れたタイヤ外側での配置とした。Ｄ＝４ｍｍとした。第１のアンテナ１６の外側のループとコの字型の電磁界結合部１７ａとの距離ｄ１２を、２ｍｍ以下とした。ただしループと結合部は直接結合していない。 [Example]
Examples 1 to 4
The RFID tags shown in FIG. 2 and FIGS. 3A to 3C were used.
The first fixing member 13 was a PET film having a vertical length of a1 = 6 mm, a horizontal length of a2 = 7 mm, and a thickness of t = 0.1 mm. The vertical length of the second fixing member 14 was b1 = 10 mm, the horizontal length was b2 = 10 mm, and the thickness was T = 1 mm. The 2nd fixing member 14 used what apply | coated the adhesive agent to the fixed surface side of the coating | covering material which consists of nylon. The third fixing member 15 was a rubber sheet. The communication frequency was 920 MHz, and the total length L17 of the second antenna 17 was 128 mm (2/5 wavelength). w: 2.1 mm, p: 7.5 mm. The RFID chip 11 and the first antenna 16 are placed on the first fixing member 13 so that the RFID chip 11 and the first antenna 16 are located on the tire outer surface side and the first fixing member 13 is located on the tire inner surface side. Formed.
The mounting position of the RFID tag 10 is 30 mm above the bead core 6a, 10 mm below the upper end of the bead filler 6b, and on the outer side of the tire away from 4 mm from the carcass ply cord 7a disposed below. Was arranged. D = 4 mm. The distance d12 between the outer loop of the first antenna 16 and the U-shaped electromagnetic field coupling portion 17a was set to 2 mm or less. However, the loop and the joint are not directly joined.
　図６に示すように、本発明によるＲＦＩＤタグ１０の第２のアンテナ１７と第３のアンテナであるカーカスプライコード７ａとのなす角度（以下、アンテナ角度αという）を、０°，３０°，６０°，９０°（直交）とした（実施例１～４）。これらのときの通信距離を測定した結果を、以下の表１に示す。
　なお、通信距離は、α＝０°である場合を１００としたときの指数である。 As shown in FIG. 6, angles formed by the second antenna 17 of the RFID tag 10 according to the present invention and the carcass ply cord 7a as the third antenna (hereinafter referred to as the antenna angle α) are 0 °, 30 °, The angles were set to 60 ° and 90 ° (orthogonal) (Examples 1 to 4). The results of measuring the communication distance at these times are shown in Table 1 below.
The communication distance is an index when α = 0 ° is taken as 100.
Figure JPOXMLDOC01-appb-T000001
  
 
　表１から、第２のアンテナ１７とカーカスプライコード７ａとが直交している場合（実施例４）に、通信距離が最大となることがわかった。
　実施例５、及び比較例１
　図６に示す本発明の好ましい例によるＲＦＩＤタグ１０の通信距離と、図７に示すような、ＲＦＩＤチップ５１と螺旋形のアンテナ５２とが物理的に結合している従来型のＲＦＩＤタグ５０との通信距離とを比較した。従来型のＲＦＩＤタグ５０のアンテナ５２の延長方向と図示しないカーカスプライコードとのなす角度は、本発明によるＲＦＩＤタグ１０と同じく９０°である。
　従来型のＲＦＩＤタグ５０の仕様を以下の表２に、比較結果を表３に示す。
　通信距離は、ＲＦＩＤタグ１０及びＲＦＩＤタグ５０を、厚さ２ｍｍのゴムシートで挟み込み、かつ、カーカスプライコードと第２のアンテナ１７との距離、及び、カーカスプライコードとアンテナ５２との距離が、５ｍｍになる位置に設置して、測定した。なお、ゴムシートとしては、ＣＢ（カーボンブラック）を２０重量部、Ｓｉを３重量部含むゴムを使用した。
　通信距離は、従来型のＲＦＩＤタグ５０の値を１００としたときの指数である。
Figure JPOXMLDOC01-appb-T000001

From Table 1, it was found that the communication distance was the maximum when the second antenna 17 and the carcass ply cord 7a were orthogonal to each other (Example 4).
Example 5 and Comparative Example 1
A conventional RFID tag 50 in which a communication distance of the RFID tag 10 according to a preferred example of the present invention shown in FIG. 6 and a RFID chip 51 and a helical antenna 52 are physically coupled as shown in FIG. Compared with the communication distance. The angle formed between the extending direction of the antenna 52 of the conventional RFID tag 50 and a carcass ply cord (not shown) is 90 ° as in the RFID tag 10 according to the present invention.
The specifications of the conventional RFID tag 50 are shown in Table 2 below, and the comparison results are shown in Table 3.
As for the communication distance, the RFID tag 10 and the RFID tag 50 are sandwiched between rubber sheets having a thickness of 2 mm, and the distance between the carcass ply cord and the second antenna 17 and the distance between the carcass ply cord and the antenna 52 are as follows: It installed in the position used as 5 mm, and measured. As the rubber sheet, a rubber containing 20 parts by weight of CB (carbon black) and 3 parts by weight of Si was used.
The communication distance is an index when the value of the conventional RFID tag 50 is 100.
Figure JPOXMLDOC01-appb-T000002
 　
Figure JPOXMLDOC01-appb-T000002
 　
Figure JPOXMLDOC01-appb-T000003
  
 
Figure JPOXMLDOC01-appb-T000003
  
 
　表３に示すように、本発明のＲＦＩＤタグ１０（実施例５）は、従来型のＲＦＩＤタグ５０（比較例１）の約１０倍の通信距離を確保できることがわかる。
　これは、本発明のＲＦＩＤタグ１０は、第２のアンテナ１７がＲＦＩＤチップ１１と物理的に結合していない。よって、アンテナ長（全長）を長くすることができ、カーカスプライコード７ａと十分な電磁界結合をさせることができる。これ対し、従来型のＲＦＩＤタグ５０では、耐久性の関係で全長を長くできないので、カーカスプライコードとの十分な電磁界結合がなされないからであると考えられる。
　また、従来型のＲＦＩＤタグ５０では、アンテナ５２を螺旋状として計算上のアンテナ長を長くしているが、その効果は少ないと考えられる。 As shown in Table 3, it can be seen that the RFID tag 10 (Example 5) of the present invention can secure a communication distance about 10 times that of the conventional RFID tag 50 (Comparative Example 1).
This is because in the RFID tag 10 of the present invention, the second antenna 17 is not physically coupled to the RFID chip 11. Therefore, the antenna length (full length) can be increased, and sufficient electromagnetic field coupling with the carcass ply cord 7a can be achieved. On the other hand, it is considered that the conventional RFID tag 50 cannot be made long because of its durability, so that sufficient electromagnetic field coupling with the carcass ply cord is not achieved.
Further, in the conventional RFID tag 50, the antenna 52 is formed in a spiral shape to increase the calculated antenna length, but it is considered that the effect is small.
実施例６～３１、比較例２～６
　図３に示すＲＦＩＤタグを３２個用意した。各ＲＦＩＤタグを、それぞれ、導電性のカーカスプライコードを有するタイヤのビードフィラー端よりも径方向下側で、かつビード端よりも径方向外側になるように、以下に述べる特徴以外は実施例４と同様にして配置した。各タイヤを車両に装着した。装着時におけるプライ－タグ距離Ｄは、１，４，５，１０，１５，２０，２５，又は３０ｍｍとし、アンテナ重なり面積率Ｒは０．２９，０．３５，０．６，又は０．６４となるように、ＲＦＩＤタグを配置した。これらについて、ＲＦＩＤタグの通信距離を測定した結果を表４に示す（通信距離指数が１００以上である組み合わせについて、表の左側から右側にかつ上から下に向うように、実施例の番号をつけた。比較例は１００未満のものについて同様に比較例番号をつけた）。表５は、各ＲＦＩＤタグの通信距離評価値Ｐを示す表である。 Examples 6 to 31 and Comparative Examples 2 to 6
32 RFID tags shown in FIG. 3 were prepared. Example 4 except for the features described below so that each RFID tag is radially lower than the bead filler end of the tire having a conductive carcass ply cord and radially outer than the bead end. Was arranged in the same manner. Each tire was mounted on the vehicle. The ply-tag distance D when mounted is 1, 4, 5, 10, 15, 20, 25, or 30 mm, and the antenna overlap area ratio R is 0.29, 0.35, 0.6, or 0.64. An RFID tag was arranged so that For these, the results of measuring the communication distance of the RFID tag are shown in Table 4 (for the combinations where the communication distance index is 100 or more, the example numbers are assigned from the left side to the right side and from top to bottom in the table. Comparative examples were similarly given comparative example numbers for those less than 100). Table 5 is a table showing the communication distance evaluation value P of each RFID tag.
これら表は、プライ－タグ距離と、アンテナ重なり面積率と、通信距離指数、及び通信距離評価値との関係示す。
　通信距離は、読み取り機（ＡＴＩＤ社製ＲＦＩＤタグリーダ）により、タグを支障なく読み取れるタイヤ表面からの距離である。表４の値は、測定した通信距離を、実用に耐えうる通信距離を１００としたときの指数で（通信距離指数）である。通信距離指数の数値が高いことが好ましい。
　ここで、実用に耐えうる通信距離とは、トラック後輪（ダブルタイヤ）のうちの内側のタイヤにＲＦＩＤタグを装着した時に、トラックの外側から読み取り可能な距離を指す。
　表４及び５から、２≦Ｐ＜７２であるＲＦＩＤタグは、通信距離指数が全て１００以上であり、３≦Ｐ＜５２であるＲＦＩＤタグは、通信距離指数が全て１０５を超えていることがわかる。
　これに対して、Ｐ＜２であるＲＦＩＤタグ、及び、Ｐ≧７２であるＲＦＩＤタグは、いずれも、通信距離が実用に耐えうる通信距離よりも短いことがわかる。
　これにより、通信距離評価値Ｐを２以上７２未満とすれば、実用に耐えうる通信距離を確保できることが確認された。 These tables show the relationship between the ply-tag distance, the antenna overlap area ratio, the communication distance index, and the communication distance evaluation value.
The communication distance is a distance from the tire surface where the tag can be read without any trouble by a reader (RFID tag reader manufactured by ATID). The values in Table 4 are index values (communication distance index) when the measured communication distance is defined as a communication distance that can withstand practical use. It is preferable that the communication distance index is high.
Here, the communication distance that can be practically used refers to a distance that can be read from the outside of the truck when the RFID tag is attached to the inner tire of the rear wheels (double tires) of the truck.
From Tables 4 and 5, RFID tags with 2 ≦ P <72 all have a communication distance index of 100 or more, and RFID tags with 3 ≦ P <52 all have a communication distance index exceeding 105. Recognize.
On the other hand, it can be seen that the RFID tag with P <2 and the RFID tag with P ≧ 72 are both shorter in communication distance than can be practically used.
Thereby, it was confirmed that if the communication distance evaluation value P is 2 or more and less than 72, a communication distance that can withstand practical use can be secured.
Figure JPOXMLDOC01-appb-T000004
  
Figure JPOXMLDOC01-appb-T000004
  
Figure JPOXMLDOC01-appb-T000005
  
Figure JPOXMLDOC01-appb-T000005
  
　以上、本発明を実施の形態及び実施例を用いて説明したが、本発明の技術的範囲は前記実施の形態に記載の範囲には限定されない。前記実施の形態に、多様な変更または改良を加えることが可能であることが当業者にも明らかである。そのような変更または改良を加えた形態も本発明の技術的範囲に含まれ得ることが、特許請求の範囲から明らかである。 As mentioned above, although this invention was demonstrated using embodiment and an Example, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the embodiment. It is apparent from the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.
　十分な通信距離を確保できるとともに、耐久性にも優れたＲＦＩＤタグを内蔵したタイヤを提供する。 Provide tires with built-in RFID tags that can secure a sufficient communication distance and have excellent durability.
１　タイヤ
２　トレッド部
３　ベルト層
４　サイドウォール部
５　ショルダー部
６　ビード部
６ａ　ビードコア
６ｂ　ビードフィラー
７　カーカスプライ
７ａ　カーカスプライコード
７ｂ　被覆ゴム
７ｃ　折り曲げ部
１０　ＲＦＩＤタグ
１１　ＲＦＩＤチップ
１２　アンテナ
１３　第１の固定部材
１４　第２の固定部材
１５　第３の固定部材
１６　第１のアンテナ
１７　第２のアンテナ
１７ａ　電磁界結合部
１７ｂ　延長部
５０　従来型のＲＦＩＤタグ
５１　ＲＦＩＤチップ
５２　螺旋形のアンテナ
ａ１　縦の長さ
ａ２　横の長さ
ｂ１　縦の長さ
ｂ２　横の長さ
Ｄ　　第２のアンテナとカーカスプライコードとの距離
ｄ１２　第１のアンテナの外側のループとコの字型の電磁界結合部との距離
ｓ１　第二アンテナから第一アンテナ外側の矩形までの距離が最も遠い部分
ｓ２　　第二アンテナから第一アンテナ外側の矩形までの距離が最も近い部分
Ｌ　　従来型のＲＦＩＤタグの全長
Ｌ１　外周の長さ
Ｌ２　第２のアンテナの第１のアンテナ１６に近接している領域の全長
Ｌ１７　第２のアンテナの全長
ｐ　　波型の延長部のピッチ（同じ側で隣り合う波のピークとピークの距離）
ｗ１　波型の延長部の幅（波の高さ）
ｗ２　従来型のＲＦＩＤタグの幅（高さ）
Ｉ　　タグ長
Ａ　　タイヤ内側
Ｂ　　タイヤ外側 DESCRIPTION OF SYMBOLS 1 Tire 2 Tread part 3 Belt layer 4 Side wall part 5 Shoulder part 6 Bead part 6a Bead core 6b Bead filler 7 Carcass ply 7a Carcass ply cord 7b Cover rubber 7c Bending part 10 RFID tag 11 RFID chip 12 Antenna 13 First fixing member 14 Second fixing member 15 Third fixing member 16 First antenna 17 Second antenna 17a Electromagnetic field coupling portion 17b Extension portion 50 Conventional RFID tag 51 RFID chip 52 Spiral antenna a1 Vertical length a2 Horizontal length b1 Vertical length b2 Horizontal length D Distance between the second antenna and the carcass ply cord d12 Distance s1 between the outer loop of the first antenna and the U-shaped electromagnetic coupling portion The part of the farthest distance from the two antennas to the rectangle outside the first antenna s2 The second antenna The portion L closest to the rectangle outside the first antenna L The total length L1 of the conventional RFID tag The outer length L2 The total length L17 of the region close to the first antenna 16 of the second antenna The second antenna The total length of the p wave pitch (the distance between adjacent waves on the same side)
Width of w1 corrugated extension (wave height)
w2 Width (height) of conventional RFID tag
I Tag length A Tire inside B Tire outside

Claims (9)

  1. 　ＲＦＩＤチップとアンテナとを備えたＲＦＩＤタグが、内蔵されたタイヤであって、
    　前記タイヤが導電性のカーカスプライコードを有するカーカスプライを有し、
    前記アンテナが、
    　前記ＲＦＩＤチップに接続される第１のアンテナと、
    　前記第１のアンテナの外部に設けられて前記第１のアンテナに電磁界結合され　る第２のアンテナとを備え、
    　前記ＲＦＩＤチップと前記第１のアンテナとが、前記ＲＦＩＤタグの第１の固定部材に固定されており、　前記ＲＦＩＤタグが、
    　前記タイヤのカーカスプライ端から、タイヤ径方向の外側の位置に配置され、
    　前記第２のアンテナが、前記カーカスプライを構成する導電性のカーカスプライコードと電磁界結合していることを特徴とするＲＦＩＤタグ内蔵タイヤ。     An RFID tag including an RFID chip and an antenna is a built-in tire,
    The tire has a carcass ply having a conductive carcass ply cord;
    The antenna is
    A first antenna connected to the RFID chip;
    A second antenna provided outside the first antenna and electromagnetically coupled to the first antenna;
    The RFID chip and the first antenna are fixed to a first fixing member of the RFID tag, and the RFID tag is
    From the carcass ply end of the tire, it is arranged at a position outside the tire radial direction,
    An RFID tag built-in tire, wherein the second antenna is electromagnetically coupled to a conductive carcass ply cord constituting the carcass ply.
  2. 　前記第２のアンテナの延長方向と前記カーカスプライコードの延長方向とが直交していることを特徴とする請求項１に記載のＲＦＩＤタグ内蔵タイヤ。 The RFID tag built-in tire according to claim 1, wherein the extension direction of the second antenna and the extension direction of the carcass ply cord are orthogonal to each other.
  3. 　前記第２のアンテナの前記第１のアンテナから所定距離以上離れた部分の形状が波型形状であることを特徴とする請求項１に記載のＲＦＩＤタグ内蔵タイヤ。 2. The RFID tag built-in tire according to claim 1, wherein a shape of a portion of the second antenna away from the first antenna by a predetermined distance or more is a corrugated shape.
  4. 　前記第２のアンテナの前記第１のアンテナから所定距離以内にある部分の長さが前記第１のアンテナの外周の長さの半分以上であることを特徴とする請求項に記載のＲＦＩＤタグ内蔵タイヤ。 The RFID tag built-in according to claim 1, wherein a length of a portion of the second antenna that is within a predetermined distance from the first antenna is not less than half of an outer circumference of the first antenna. tire.
  5. 　前記第１の固定部材とは反対側から、前記ＲＦＩＤチップと、前記第１のアンテナと、前記第２のアンテナの少なくとも前記第１のアンテナとの電磁界結合している部分とを覆う、第２の固定部材を更に設けたことを特徴とする、請求項１に記載のＲＦＩＤタグ内蔵タイヤ。 Covering the RFID chip, the first antenna, and at least a portion of the second antenna that is electromagnetically coupled to the first antenna from a side opposite to the first fixing member; 2. The RFID tag built-in tire according to claim 1, further comprising two fixing members.
  6. 　ＲＦＩＤチップとアンテナとを備えたＲＦＩＤタグが内蔵されたタイヤであって、
    　前記タイヤが導電性のカーカスプライコードを有しカーカスプライを有し、
    　前記アンテナが、
    　前記ＲＦＩＤチップに接続される第１のアンテナと、
    　前記第１のアンテナの外部に設けられて前記第１のアンテナに電磁界結合される第２のアンテナとを備え、
    　前記第２のアンテナと前記カーカスプライコード間の距離をＤ、
    　前記第２のアンテナとカーカスプライコードとの重なり面積をＡ、
    　前記第２のアンテナの面積をＳ、
    　前記重なり面積Ａを前記第２のアンテナの面積Ｓで除した値をアンテナ重なり面積率Ｒ、
    　前記距離Ｄを前記アンテナ重なり面積率Ｒで除した値を通信距離評価値Ｐとしたとき、
    　前記通信距離評価値Ｐが２以上７２未満であることを特徴とするＲＦＩＤタグ内蔵タイヤ。     A tire incorporating an RFID tag having an RFID chip and an antenna,
    The tire has a conductive carcass ply cord and a carcass ply;
    The antenna is
    A first antenna connected to the RFID chip;
    A second antenna provided outside the first antenna and electromagnetically coupled to the first antenna;
    A distance between the second antenna and the carcass ply cord is D,
    The overlapping area of the second antenna and the carcass ply cord is A,
    The area of the second antenna is S,
    A value obtained by dividing the overlapping area A by the area S of the second antenna is an antenna overlapping area ratio R,
    When a value obtained by dividing the distance D by the antenna overlap area ratio R is a communication distance evaluation value P,
    The RFID tag built-in tire, wherein the communication distance evaluation value P is 2 or more and less than 72.
  7. 　前記Ｐが３以上５２未満であることを特徴とする請求項６に記載のＲＦＩＤタグ内蔵タイヤ。 The tire with a built-in RFID tag according to claim 6, wherein the P is 3 or more and less than 52.
  8. 　前記第２のアンテナの延長方向と前記カーカスプライコードの延長方向とが直交していることを特徴とする請求項６に記載のＲＦＩＤタグ内蔵タイヤ。 The RFID tag built-in tire according to claim 6, wherein the extension direction of the second antenna and the extension direction of the carcass ply cord are orthogonal to each other.
  9. 　前記第２のアンテナの形状が波型形状であることを特徴とする請求項６に記載のＲＦＩＤタグ内蔵タイヤ。 The RFID tag built-in tire according to claim 6, wherein the shape of the second antenna is a corrugated shape.
PCT/JP2017/002328 2016-01-25 2017-01-24 Tire with embedded rfid tag WO2017130956A1 (en)

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JP2016-011786 2016-01-25
JP2016011786A JP6612141B2 (en) 2016-01-25 2016-01-25 RFID tag built-in tire
JP2016011787A JP6650767B2 (en) 2016-01-25 2016-01-25 RFID tag built-in tire
JP2016-011787 2016-01-25

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US10647166B2 (en) * 2018-10-03 2020-05-12 Toyo Tire Corporation Tire and tire manufacturing method
WO2020163924A1 (en) 2019-02-11 2020-08-20 Ceitec - Centro Nacional De Tecnologia Eletrônica Avançada S.A. Tyre containing an rfid tag
CN111942085A (en) * 2019-05-17 2020-11-17 通伊欧轮胎株式会社 Tyre for vehicle wheels
JP2021044674A (en) * 2019-09-10 2021-03-18 株式会社フェニックスソリューション Rfid tag, tire with built-in rfid tag, and method for adjusting resonance frequency of rfid tag
CN113439033A (en) * 2019-02-18 2021-09-24 普利司通欧洲有限公司 Improved RFID device for tire
WO2024034230A1 (en) * 2022-08-10 2024-02-15 株式会社ブリヂストン Pneumatic tire
WO2024042802A1 (en) * 2022-08-26 2024-02-29 株式会社ブリヂストン Pneumatic tire
JP7464833B2 (en) 2020-05-28 2024-04-10 横浜ゴム株式会社 Pneumatic tires

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10647166B2 (en) * 2018-10-03 2020-05-12 Toyo Tire Corporation Tire and tire manufacturing method
WO2020163924A1 (en) 2019-02-11 2020-08-20 Ceitec - Centro Nacional De Tecnologia Eletrônica Avançada S.A. Tyre containing an rfid tag
CN113439033A (en) * 2019-02-18 2021-09-24 普利司通欧洲有限公司 Improved RFID device for tire
JP2022519907A (en) * 2019-02-18 2022-03-25 ブリヂストン ヨーロッパ エヌブイ／エスエイ Improved RFID device for tires
JP7317132B2 (en) 2019-02-18 2023-07-28 ブリヂストン ヨーロッパ エヌブイ／エスエイ Improved RFID device for tires
CN111942085A (en) * 2019-05-17 2020-11-17 通伊欧轮胎株式会社 Tyre for vehicle wheels
JP2021044674A (en) * 2019-09-10 2021-03-18 株式会社フェニックスソリューション Rfid tag, tire with built-in rfid tag, and method for adjusting resonance frequency of rfid tag
JP7174415B2 (en) 2019-09-10 2022-11-17 株式会社フェニックスソリューション RFID tag, RFID tag built-in tire, and method for adjusting resonance frequency of RFID tag
JP7464833B2 (en) 2020-05-28 2024-04-10 横浜ゴム株式会社 Pneumatic tires
WO2024034230A1 (en) * 2022-08-10 2024-02-15 株式会社ブリヂストン Pneumatic tire
WO2024042802A1 (en) * 2022-08-26 2024-02-29 株式会社ブリヂストン Pneumatic tire

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