JP2007328378A - Ic tag attaching structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an IC tag attaching structure providing a sufficient transmission/reception capability even when a general-purpose IC tag is attached to a conductive article such as a metal product. <P>SOLUTION: The IC tag 11 is attached to an article, for example, a conductive metal product 14, via an insulator 15. The insulator 15 is preferably formed to have a thickness slightly larger than of that of L/(4ε) with respect to the relative permittivity ε of the insulator and the wavelength L of an electromagnetic wave for radio communication. Also, the insulator 15 preferably has an antenna length-direction size at least 1/2 of a wavelength and has an antenna width-direction size about 1/4 of the wavelength. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an IC tag mounting structure, and more particularly, an IC that can satisfactorily perform wireless communication between an IC tag and a transmission / reception device even when the article to which the IC tag is attached is a conductive article, for example, a metal product. The tag mounting structure, for example, for each bicycle when building a bicycle or motorcycle management system that is a metal product, an IC tag holding data for each motorcycle is attached to each bicycle or motorcycle metal part The present invention relates to an IC tag mounting structure that is optimal as a mounting structure and can be applied to a plastic part of a motorcycle.

  As a physical distribution management method for various articles, an IC tag holding various data for each article is attached to each article, and the data of the IC tag is read by a transmission / reception device, for example, a reader, thereby efficiently managing a large number of articles. Things have been done. At this time, if the IC tag is attached to a conductive article such as a metal product, the transmission output of the IC tag becomes extremely weak, so the radio wave of the IC tag attached to the conductive article may not be detected. It may become impossible.

As one means for solving this, an impedance of 1.1 to 3 times the impedance of the antenna unit and transmission between the transmission unit of the IC tag that transmits individual ID code data at predetermined time intervals and the antenna unit A matching circuit that matches the impedance of the part is provided (for example, see Patent Document 1).
JP 2004-70413 A

  However, the IC tag provided with the matching circuit as described above has a problem in that it has a problem in manufacturing cost or needs to be used depending on a target article.

  Accordingly, an object of the present invention is to provide an IC tag mounting structure capable of obtaining sufficient transmission / reception capability even when a general-purpose IC tag is mounted on a conductive article such as a metal product.

  In order to achieve the above object, an IC tag mounting structure according to the present invention is a structure in which an IC tag for authentication that transmits and receives an authentication signal by wireless communication with a transmission / reception device is attached to an article. Is attached to the article via an insulator, and in particular, the insulator has a relative dielectric constant (ε) of the insulator and a wavelength (L) of electromagnetic waves for performing the wireless communication. (4ε) thickness or slightly thicker, the insulator has a relative dielectric constant of 3 or more, and the insulator has a length in the antenna length direction of ½ or more of the wavelength, It is characterized in that the dimension in the antenna width direction is about 1/4 of the wavelength.

  Further, the article is a bicycle or a motorcycle which is a conductive article, and the IC tag holds different data for each bicycle or each bike, and the transmission / reception device is provided at an entrance / exit of a bicycle parking lot. It is characterized by having.

  Further, the IC tag is attached in a state in which it is substantially impossible to remove from the conductive article, and the thickness between the insulator and the article is 10 μm or more from the insulator. It is characterized by interposing a large-sized metal foil or metal plate.

  According to the IC tag mounting structure of the present invention, even if a general-purpose IC tag is mounted on a conductive article such as a metal product, the transmission / reception capability does not decrease. Therefore, management of metal products and the like can be efficiently performed using a general-purpose IC tag. In addition, by using an insulator having a relative dielectric constant of 3 or more, preferably 8 or more, the thickness of the insulator can be reduced to a few millimeters, so the degree of freedom in mounting the IC tag is improved. To do. By attaching an IC tag to a bicycle or motorcycle, which is one of metal products, via an insulator, it is possible to efficiently manage bicycles and motorcycles at a bicycle parking lot. In addition, when the IC tag is attached to a plastic article, for example, a plastic member such as a scooter body, good transmission / reception can be performed by interposing a metal foil between the insulator and the article.

  1 is a perspective view showing an example of an IC tag mounting structure according to the present invention, FIG. 2 is a perspective view showing an example of the shape of the IC tag, and FIG. 3 is a perspective view showing another example of the shape of the IC tag. 4 is an explanatory view showing an example in which the IC tag mounting structure of the present invention is applied to a bicycle management system.

  First, as shown in FIG. 2 and FIG. 3, the IC tag 11 includes an IC chip 12 having a function of holding data and transmitting the data to an external reader, and an antenna 13 connected to the IC chip 12. It consists of two parts. The IC chip 12 can be arbitrarily used in various structures, shapes, and functions that have been used in the past, and detailed description thereof will be omitted.

  The antenna 13 may be a metal thin wire 13a as shown in FIG. 2 or a metal foil 13b having a sufficiently narrow width with respect to the length as shown in FIG. In a dipole antenna, both the antenna lengths of the transmission / reception apparatus and the IC tag 11 are equal, and when the frequency of the transmission / reception apparatus is, for example, a frequency of 2.45 GHz, both antenna lengths are from 6.12 cm of 1/2 wavelength. The length is set to a few percent shorter. The shortening rate of the antenna with respect to the ½ wavelength can be determined by the thickness of the antenna. When the metal foil 13b is used as an antenna, for example, a copper foil on a flexible substrate can be used. When the metal thin wire 13a is used as an antenna, for example, a metal thin wire such as copper or aluminum, or a metal such as iron. A material in which a fine wire is gold-plated can be used.

  When such an IC tag 11 is directly attached to a conductive article, for example, a metal product, electromagnetic waves around the IC tag 11 are affected by the metal, and the transmission / reception distance of the IC tag 11 is greatly reduced. If the distance from the metal is ¼ or more of the wavelength of the electromagnetic wave, the metal is hardly affected. Furthermore, by making the distance between the metal and the IC tag 11 slightly longer than ¼ of the wavelength, it is possible to resonate with the antenna 13 of the IC tag 11 using the metal as a reflector to improve the antenna efficiency.

  For example, when the frequency of the electromagnetic wave used for wireless communication between the transmission / reception device and the IC tag 11 is 2.45 GHz, the distance of the quarter wavelength is 3.06 cm. However, it is not realistic to attach the IC tag 11 on the metal product at such a distance, and it becomes difficult to handle the metal product, or when the IC tag 11 is attached to a bicycle, a motorcycle, etc., the IC tag 11 is attached to the clothes. There are problems such as being caught. Moreover, it is not preferable in terms of appearance.

  Therefore, in the present invention, as shown in FIG. 1, when the IC tag 11 is attached to the metal product 14, an insulator 15 is interposed between the two. Any material can be used for the insulator 15 as long as it is an insulator. The thickness of the insulator 15 is L / (relative to the relative dielectric constant (ε) of the insulator 15 and the wavelength (L) of the electromagnetic wave. 4ε) or slightly thicker, for example, about 1 to 5%. For example, when quartz having a relative dielectric constant of 3.8 is used as the insulator 15, if the frequency is 2.45 GHz, L / (4ε) is 8 mm. Therefore, the insulator 15 slightly thicker than this, for example, The insulator 15 formed to a thickness of 3% and a thickness of 8.24 mm is used.

  Thereby, antenna efficiency can be improved by using the metal product 14 as a reflector. Furthermore, the insulator 15 using the alumina compact with a relative dielectric constant of 8.5 can be reduced to a thickness of 3.6 mm if the frequency is 2.45 GHz. When the frequency is 13.56 MHz, for example, by using a ceramic insulator having a relative dielectric constant of 300, the thickness of the insulator 15 can be about 1.8 cm. The size of the insulator 15 may be about ½ or more of the wavelength in the antenna length direction and about ¼ of the wavelength in the antenna width direction. There are times when a sufficient effect cannot be obtained.

  In this way, by attaching the IC tag 11 to the metal product 14 via the insulator 15, it is possible to reliably perform wireless communication with the transmission / reception device regardless of circular polarization or linear polarization by eliminating the adverse effects of metal. be able to. Further, since the distance between the IC tag 11 and the metal product 14 can be reduced to L / (4ε) by interposing the insulator 15 as compared with the case of air insulation, the handling of the metal product 14 is adversely affected. The IC tag 11 is not caught on clothes, and the design of the metal product 14 is not impaired. Furthermore, since the antenna efficiency can be made constant by processing the insulator 15 accurately, stable transmission / reception performance can be obtained.

  The means for attaching the IC tag 11 to the metal product 14 via the insulator 15 can be arbitrarily selected according to the shape, purpose of use, etc. of the metal product 14. For example, as shown in FIG. 3, the IC tag 11 and the insulator 15 may be fixed by the adhesive tape 16, and the metal product 14, the insulator 15, and the IC tag 11 can be fixed with an adhesive, respectively. .

  When the same IC tag 11 is attached to a non-conductive article, for example, a plastic product, the IC tag 11 is attached to an insulator 15 having a thickness of L / (4ε), and the thickness is 10 μm below the insulator 15. As described above, the antenna sensitivity of the IC tag 11 can be increased by interposing a metal foil such as aluminum having a size (area) larger than that of the insulator 15. The thickness of the metal foil is arbitrary, and a metal plate with a thickness of several mm can be used. However, the effect of improving the antenna sensitivity, that is, improving the transmission / reception performance hardly changes, and the weight increases. And cost increases. The size (area) of the metal foil may be equal to or greater than the size (area) of the insulator 15, and an appropriate size can be selected according to the size of the mounting portion.

  By applying the IC tag mounting structure of the present invention to various articles, the articles can be effectively used for managing various articles regardless of whether the articles are conductive or non-conductive. For example, as shown in FIG. 4, the IC tag 11 is fixed to the frame 18 of the bicycle 17 via the insulator 15 with the adhesive tape 16, and the transmission / reception device (leader) 20 is attached to the pillar 19 at the entrance / exit of the bicycle parking lot. A bicycle management system at a bicycle parking lot or the like can be easily constructed by providing and forming an authentication signal between the IC 12 and the reader 20.

  The data necessary for managing the bicycle 17 includes, for example, a contact method such as an address, name, and telephone as the owner's information, as well as the color, axle distance, wheel diameter, registration information as the purchase destination, purchase as the characteristics of each bicycle 17 Date, registration date, registration number, name of designated bicycle parking lot for bicycle parking lot, period of bicycle parking and other rights information. When the IC chip 12 that can be written to the IC tag 11 attached to the bicycle 17 is used, these data may be written to the IC chip 12, respectively. If an IC chip 12 that cannot be written is used, only an address number is written to the IC chip 12, and data corresponding to the address number is recorded on an external server via a server attached to the reader or a network. You just have to.

  The IC tag 11 can be attached by, for example, a method in which the IC tag 11 is bonded to the surface of the insulator 15 in advance with an adhesive, and the insulator 15 is fixed together with the IC tag 11 by the adhesive tape 16. At this time, when the adhesive tape 16 is peeled from the frame 18 of the bicycle 17 by appropriately setting the adhesive strength of the adhesive, the adhesive strength of the adhesive tape 16, and the bonding strength between the IC chip 12 and the antenna 13, the IC chip 12 can be separated to the insulator 15 side, and the antenna 13 can be separated to the adhesive tape 16 side, so that the IC tag 11 cannot be removed from the bicycle 17 as it is.

  By separating the antenna 13 in this way, the IC tag 11 can be made substantially non-reusable. As a result, even if the IC tag 11 is stolen and pasted on another bicycle, it does not operate normally, so that impersonation can be prevented, and the relationship between the bicycle 17 and the IC tag 11 can be made one-on-one. As a result, it is possible to reliably manage bicycles with bicycle parking fees and bicycle taxes. In addition, since the coupling strength between the IC chip 12 and the antenna 13 can be lowered and the overall strength can be lowered as compared with the conventional IC tag considering general reuse, the manufacturing cost of the IC tag 11 can be reduced. Reduction can also be achieved. Further, the insulator 15 and the adhesive tape 16 can be appropriately colored and printed, and can be used as a registration sticker for the bicycle 17.

  Further, it is desirable that the IC tag 11 be attached to a height that can be read by the same reader 20 even for bicycles of various sizes for adults and children. The front and sides of the frame 18 from the front wheel handle post to the tip of the fork are suitable as a place where the height can be freely selected without being hidden by the human body riding the bicycle, and the height is set at such a part. Then, the IC tag 11 may be attached via the insulator 15 in a direction orthogonal to the front-rear direction center line of the bicycle 17.

  At this time, since the antenna 13 faces in a substantially vertical direction from the shape of the normal frame 18, the antenna of the reader 20 is also installed in the substantially vertical direction. Thereby, the reader 20 can reliably read the authentication signal of the IC tag 11 from the front surface or side surface of the bicycle 17. Note that when the circular polarization method is used for wireless communication between the IC tag 11 and the reader 20, the rotation directions of the antenna 13 of the IC tag 11 and the antenna of the reader 20 may be matched in accordance with the polarization method. .

  The antenna of the reader 20 is installed at the position facing the IC tag 11 attached to the bicycle 17 with the same polarization plane. The reader 20 is fixed at the entrance / exit of the bicycle parking lot, and various management based on the data of each bicycle is performed by reading the data of the IC tag 11 attached to the bicycle entering / leaving the bicycle parking lot by a wireless communication method. Can do. For example, by recording and managing the entry and exit of bicycles, it is possible to grasp the usage status of each bicycle and use it for billing calculations, or to create management data such as the availability of bicycle parking lots.

  Further, in a bicycle parking lot where a bicycle and a motorcycle are mixed, the IC tag 11 can be attached to the motorcycle in the same manner, so that the bicycle can be managed in the same manner as a bicycle. When the IC tag 11 is attached to a plastic part such as the front of the scooter, the antenna sensitivity of the IC tag 11 is increased by interposing an aluminum foil having a thickness of 10 μm or more under the insulator 15 as described above. Can be increased. In addition, the leader 20 can also be installed in multiple places as needed.

  Furthermore, by attaching the IC tag 11 to the bicycle 17 or the motorcycle as described above, illegal parking, neglected bicycles, and theft can be dealt with. For example, by reading the data of an IC tag of a bicycle that has been neglected using a portable reader, it is possible to easily check the owner information, the presence or absence of a theft report, and the necessary processing can be performed quickly. .

  In addition to the management of bicycles and motorcycles as described above, the IC tag 11 is attached to various luggage and items as described above, and the information of each article is read by a reader installed at the entrance of a warehouse or delivery place. Thus, management and sorting determined for each article can be reliably performed. In particular, by attaching an IC tag 11 formed in advance to a three-layer structure of an IC tag 11, an insulator 15 and a metal foil to various articles, the same type of IC is used regardless of the material (conductive or non-conductive) of the article. The tag 11 can be used for transmission and reception with the same antenna efficiency, and various items can be managed easily and reliably.

It is a perspective view which shows one example of the attachment structure of the IC tag of this invention. It is a perspective view which shows the example of 1 shape of an IC tag. It is a perspective view which shows the other example of a shape of IC tag. It is explanatory drawing which shows an example which applied the attachment structure of the IC tag of this invention to the management system of a bicycle.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... IC tag, 12 ... IC chip, 13 ... Antenna, 14 ... Metal product, 15 ... Insulator, 16 ... Adhesive tape, 17 ... Bicycle, 18 ... Frame, 19 ... Pillar, 20 ... Transceiver (reader)

Claims (9)

  An IC tag having a structure in which an IC tag for authentication that transmits and receives an authentication signal by wireless communication with a transmission / reception device is attached to an article, and the IC tag is attached to the article via an insulator. Mounting structure.   The insulator is formed to have a thickness of L / (4ε) or slightly thicker than a relative dielectric constant (ε) of the insulator and a wavelength (L) of an electromagnetic wave for performing wireless communication. The IC tag mounting structure according to claim 1.   The IC tag mounting structure according to claim 2, wherein the insulator has a relative dielectric constant (ε) of 3 or more.   4. The insulator according to claim 1, wherein a dimension in the antenna length direction is ½ or more of a wavelength, and a dimension in the antenna width direction is about ¼ of a wavelength. IC tag mounting structure.   The IC tag according to any one of claims 1 to 4, wherein the article is a bicycle or a motorcycle, and the IC tag holds different data for each bicycle or each motorcycle. Construction.   6. The IC tag mounting structure according to claim 5, wherein the transmission / reception device is provided at an entrance / exit of a bicycle parking lot.   The IC tag attachment structure according to any one of claims 1 to 6, wherein the IC tag is attached in a state in which the IC tag is substantially impossible to be removed from the article.   8. The IC tag mounting structure according to claim 1, wherein a metal is interposed between the insulator and the article.   9. The IC tag mounting structure according to claim 8, wherein the metal is a metal foil having a thickness of 10 [mu] m or more and a size larger than that of the insulator.

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