JP7585672B2 - RF tagged item holder - Google Patents

Description

The present invention relates to a fixture for holding items equipped with RF tags (RF: Radio Frequency), a medium used for wireless individual identification.

In automatic identification technology that uses wireless communication, the information medium attached to an object is called an RF tag. RF tags are also called wireless tags, IC tags, or RFID tags.

Metal fixtures are generally used for displaying or storing items with RF tags attached (hereafter referred to as RF tagged items). This is because, in order to place multiple RF tagged items on one shelf wall (shelf board), the fixture needs to be strong enough to support the weight of multiple RF tagged items.

The RF tag attached to an item has an antenna that supports the frequency band used by the RF tag and an IC chip that connects to it in order to perform wireless communication. RF tags can use the LF (Low Frequency) and HF (High Frequency) frequency bands for wireless communication, but RF tags that use the UHF band (e.g., 860 to 960 MHz) for wireless communication are becoming mainstream.

The metal that makes up the fixtures has the property of blocking the wireless communication of RF tags. If an RF tag attached to an item with an RF tag comes into contact with or is in close proximity to the metal surface of the fixtures, the wireless communication of the RF tag will be blocked by the metal that makes up the fixtures.

For this reason, metal fixtures on which RF-tagged items are placed must be designed so as not to interfere with the wireless communication of the RF tags attached to the RF-tagged items.

As an invention related to fixtures that do not impede wireless communication of RF tags attached to RF-tagged items, Patent Document 1 discloses a spacer made of a low dielectric material containing foamed resin that defines the distance between the antenna of an RF tag and a metal surface. Even if an RF tag with the spacer disclosed in Patent Document 1 on its back side is attached to a metal fixture (e.g., a desk), the effect of the spacer means that the RF tag is not affected by the metal fixture.

JP 2007-241788 A

RF-tagged items that can be placed on metal fixtures include a variety of items, including merchandise, books, and documents. The specifications of the RF tags on RF-tagged items are often determined by the item to which the RF tag is attached. Given this, it is thought that measures to eliminate the effects of metal should be implemented in the metal fixtures rather than in the RF tags.

The present invention aims to provide metal fixtures that do not impede wireless communication of an RF tag even when the RF tag of an RF-tagged item comes into contact with or is in close proximity to a metal surface.

The present invention, which solves the above-mentioned problems, is a metal fixture for placing RF-tagged articles, which are articles having an RF tag attached, and comprises at least one wall portion made of metal, the wall portion being formed by laminating, in order, a dielectric layer having a sheet resistance of 1000 Ω/sq or more, a dielectric constant of 10 or less, and a thickness of 3 mm or more, a lattice-shaped metal layer , and a plate-shaped metal layer, the lattice-shaped metal layer having the dielectric layer laminated thereon , the pair of side wall portions and the shelf wall portion being the wall portions with which the RF tag comes into contact or is in close proximity, and the fixture for RF-tagged articles is characterized in that it comprises a dielectric wall portion using the pair of side wall portions and the shelf wall portion as the plate-shaped metal layer .
Furthermore, in the fixture for RF-tagged items of the present invention, it is desirable to attach the lattice-shaped metal layer having the dielectric layer laminated thereon to the pair of side wall portions and the shelf wall portion using a weak adhesive, and it is further desirable to attach the lattice-shaped metal layer having the dielectric layer laminated thereon to the pair of side wall portions and the shelf wall portion using a removable adhesive.

In order to achieve the object of the present invention, the fixture for RF tagged items according to the present invention is configured to utilize the dielectric layer to prevent the RF tag from being affected by the plate-shaped metal layer. Furthermore, by providing the lattice-shaped metal layer, the rigidity of the dielectric wall is increased and the RF tag becomes easier to read.

FIG. 2 is a diagram illustrating the overall configuration of the item display fixture. FIG. 2 is a diagram for explaining an article with an RF tag. FIG. 2 is a diagram illustrating an RF tag. FIG. 1 is a diagram illustrating the structure of the placement surface of an item display unit. 5A and 5B are diagrams illustrating the effect of a dielectric wall portion.

The article display fixture of the present invention will be described below with reference to the drawings. Please note that the technical scope of the present invention is not limited to the contents of the embodiments described below, but extends to the inventions described in the claims and their equivalents.

Figure 1 is a diagram explaining the overall configuration of a display unit 1 for RF tagged items according to this embodiment. The display unit 1 for RF tagged items according to the present invention is a display unit configured to be capable of holding multiple RF tagged items 2, which are items 20 with RF tags 21 attached.

Figure 2 is a diagram illustrating an RF tagged item 2. The RF tagged item 2 is an item 20 to which an RF tag 21 is attached. In Figure 2, the item 20 to which the RF tag 21 is attached is a cardboard box, but the item 20 to which the RF tag 21 is attached can be a variety of items such as a product, a book, or a document. In Figure 2, the surface of the item 20 to which the RF tag 21 is attached is the bottom surface of the item 20. The surface of the item 20 to which the RF tag 21 is attached can also be the side surface of the item 20.

Figure 3 is a diagram for explaining the RF tag 21. The RF tag 21 attached to the item 20 is in the form of a sticker label. The shape of the RF tag 21 is a horizontally long, approximately rectangular shape. As shown in Figure 3, the layer structure of the RF tag 21 is a laminated structure of a surface sheet 210 that becomes the surface of the RF tag 21, a first adhesive layer 211 formed using an adhesive or the like, an inlay 213 mounting an IC chip 217 and an antenna 212 connected to it, and a second adhesive layer 214 formed using an adhesive or the like. The RF tag 21 is attached to the item 20 using the second adhesive layer 214. Note that the layer structure of the RF tag 21 illustrated in Figure 3 is merely an example, and the layer structure of the RF tag 21 attached to the item 20 is arbitrary.

The RF tag 21 is equipped with an antenna 212 that supports the UHF band. The antenna 212 mounted on the RF tag 21 is composed of a pair of planar elements 216 and an antenna matching circuit 215. The IC chip 217 is connected to the antenna matching circuit 215, and the antenna matching circuit 215 is disposed between the pair of planar elements 216.

As shown in FIG. 1, the RF tagged item display 1 according to this embodiment has at least a top wall 10a, a pair of side walls 10b, and a back wall 10c as wall sections 10 made of at least metal. Furthermore, the RF tagged item display 1 according to this embodiment has at least one shelf wall section 10d (four in this embodiment) as wall sections 10 made of at least metal so that multiple RF tagged items 2 can be placed on it.

In the RF tagged item display unit 1 according to this embodiment, the wall portion 10 used for placing the RF tagged item 2 is the shelf wall portion 10d. The RF tag 21 is attached to the bottom surface of the item 20, and each item 20 is placed so that the bottom surface to which the RF tag 21 is attached is in contact with the wall portion 10 used for placing the RF tagged item 2.

If the RF tag 21 of the RF tagged item 2 comes into contact with or close to the wall 10 of the RF tagged item display 1 without any special measures, the wireless communication of the RF tag 21 will be blocked due to the influence of the metal that constitutes the wall 10 of the RF tagged item display 1. Therefore, in the RF tagged item display 1 according to this embodiment, a special measure is implemented in the wall 10 that may come into contact with or close to the RF tag 21 of the RF tagged item 2 so that the wireless communication of the RF tag 21 is not blocked even if the RF tag 21 of the RF tagged item 2 comes into contact with or close to the wall 10 of the RF tagged item display 1. In the present invention, the wall 10 with this special measure is called the dielectric wall 11.

Figure 4 is a diagram explaining the structure of the dielectric wall portion 11 of the fixture 1 for RF tagged items. Figure 4(a) is a diagram explaining the layer configuration of the dielectric wall portion 11. Figure 4(b) is a diagram explaining the lattice-shaped metal layer 111 laminated on the dielectric wall portion 11. Figure 4(c) is a diagram explaining the state in which the lattice-shaped metal layer 111 laminated with the dielectric layer 112 is attached to the plate-shaped metal layer 110 by the adhesive layer 113.

As shown in FIG. 4(a), the dielectric wall 11 of the RF tagged item display 1 has a laminated structure of a dielectric layer 112 having a sheet resistance of 1000 Ω/sq or more and a dielectric constant of 10 or less, a lattice-shaped metal layer 111, and a plate-shaped metal layer 110.

As shown in FIG. 4(b), the lattice-like metal layer 111 is a layer in which meshes 111a without metal are regularly arranged and the plate-like metal is arranged in a lattice (mesh) shape. The lattice-like metal layer 111 can be manufactured by crossing linear metal material, but can also be manufactured by drilling meshes 111a into a plate-like metal. Note that in FIG. 4(b), the meshes 111a are approximately square, but the meshes 111a may also be diamond-shaped.

The layer in contact with or close to the RF tag 21 is the dielectric layer 112. In the RF tagged item fixture 1 according to this embodiment, the thickness of the dielectric layer 112 of the dielectric wall 11 is set to 3 mm or more, and the RF tag 21 of the RF tagged item 2 is spaced 3 mm or more from the lattice-shaped metal layer 111. As a material having a sheet resistance of 1000 Ω/sq or more and a dielectric constant of 10 or less, for example, polyethylene terephthalate (PET) can be used.

When a commercially available fixture having a metal wall is used as the fixture 1 for RF-tagged goods, the wall of the metal fixture used as the fixture 1 for RF-tagged goods can be used as the plate-shaped metal layer 110. In this case, as shown in FIG. 4(c), the dielectric wall portion 11 can be realized by attaching the lattice-shaped metal layer 111 with the dielectric layer 112 laminated thereon to the wall of the fixture using the adhesive layer 113. In this case, it is not necessarily necessary to firmly adhere the lattice-shaped metal layer 111 with the dielectric layer 112 laminated thereon to the plate-shaped metal layer 110. If the lattice-shaped metal layer 111 with the dielectric layer 112 laminated thereon is attached to the wall of the fixture used as the plate-shaped metal layer 110 using the adhesive layer 113 using a weak adhesive that can be peeled off after attachment, it becomes easy to separate and collect the fixture 1 for RF-tagged goods when it is disposed of. In addition, if the lattice-shaped metal layer 111 laminated with the dielectric layer 112 is attached to the wall of the fixture with an adhesive layer 113 using a removable adhesive that can be attached and removed repeatedly, the lattice-shaped metal layer 111 laminated with the dielectric layer 112 can be reused when using the metal fixture as the fixture 1 for RF-tagged items according to this embodiment.

As mentioned above, the dielectric wall 11 described using FIG. 4 is used for the wall 10 that may come into contact with or be in close proximity to the RF tag 21 of the RF tagged item 2.

The dielectric wall portion 11 described with reference to FIG. 4 is used at least as the wall portion 10 for placing the RF-tagged item 2. In the RF-tagged item display unit 1 described with reference to FIG. 1, the wall portion 10 for placing the RF-tagged item 2 becomes the shelf wall portion 10d. In the wall portion 10 for placing the RF-tagged item 2, the placement surface for the RF-tagged item 2 becomes the dielectric layer 112 of the dielectric wall portion 11.

In addition, in the fixture 1 for RF-tagged items described using FIG. 1, the dielectric wall portion 11 described using FIG. 4 is also used for the side wall portion 10b. This is because it is considered that the RF tag 21 will be attached to the side of the RF-tagged item 2.

In the display unit 1 for RF-tagged items described with reference to Figure 1, the top wall 10a and back wall 10c are walls 10 made of metal only. This is because when radio waves are irradiated from the front of the display unit 1 for RF-tagged items, they are reflected by the top wall 10a and back wall 10c, improving the reading performance of the RF tag 21 of the RF-tagged item 2.

Figure 5 is a diagram explaining the effect of the dielectric wall portion 11. In Figure 5, the dielectric wall portion 11 is illustrated as a shelf wall portion 10d. As described above, in the display unit 1 for RF-tagged items according to this embodiment, a dielectric layer 112 is laminated on the dielectric wall portion 11, so that at least the dielectric layer 112 is present between the RF tag 21 of the RF-tagged item 2 and the plate-shaped metal layer 110.

The dielectric layer 112 is made of a low dielectric material with a sheet resistance of 1000 Ω/sq or more and a dielectric constant of 10 or less. Therefore, if the distance between the RF tag 21 and the plate-shaped metal layer 110 is made 3 mm or more, that is, if the thickness of the dielectric layer 112 is made 3 mm or more, it is possible to prevent the radio waves emitted by the reader/writer from being absorbed by the plate-shaped metal layer 110, and the RF tag 21 will be less susceptible to the effects of the plate-shaped metal layer 110.

In addition, in the dielectric wall portion 11 of this embodiment, a lattice-shaped metal layer 111 is provided between the dielectric layer 112 and the plate-shaped metal layer 110. When the rigidity of the plate-shaped metal layer 110 is low, the rigidity of the plate-shaped metal layer 110 can be increased by using the lattice-shaped metal layer 111. Furthermore, by providing the lattice-shaped metal layer 111 between the dielectric layer 112 and the plate-shaped metal layer 110, the RF tag 21 becomes easier to read. This is because, as shown in FIG. 4(b), the lattice-shaped metal layer 111 has multiple meshes 111a that are not metal, and therefore the radio waves that pass through the dielectric layer 112 and are absorbed by the lattice-shaped metal layer 111 leak out to the meshes 111a.

REFERENCE SIGNS LIST 1 RF tagged article holder 10 Wall 10a Top wall 10b Side wall 10c Back wall 10d Shelf wall 11 Dielectric wall 110 Plate-shaped metal layer 111 Lattice-shaped metal layer 111a Mesh 112 Dielectric layer 2 RF tagged article 20 Article 21 RF tag

Claims (3)

A metal fixture for placing RF tagged items, which are items with RF tags attached,
The wall portion includes a top wall portion, a pair of side wall portions, a back wall portion, and at least one shelf wall portion, and the wall portion includes at least one metal.
a dielectric wall portion in which a dielectric layer having a sheet resistance of 1000 Ω/sq or more, a dielectric constant of 10 or less, and a thickness of 3 mm or more, a lattice-shaped metal layer , and a plate-shaped metal layer are laminated in this order , the lattice-shaped metal layer having the dielectric layer laminated thereon is attached to the pair of side wall portions and the shelf wall portions which become the wall portions with which the RF tag comes into contact or is in close proximity, and the pair of side wall portions and the shelf wall portions are used as the plate-shaped metal layer.
A display for RF tagged items, characterized in that: The display rack for RF tagged items as described in claim 1 , characterized in that the lattice-shaped metal layer laminated with the dielectric layer is attached to the pair of side wall portions and the shelf wall portion using a weak adhesive. A display rack for RF tagged items as described in claim 1 , characterized in that the lattice-shaped metal layer laminated with the dielectric layer is attached to the pair of side wall portions and the shelf wall portion using a removable adhesive.

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