JP2010041126A - Rfid tag, antenna apparatus for rfid system, and communication device of rfid system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an RFID tag excellent in shock resistance and durability, and having favorable communication capability, and to provide an antenna apparatus for an RFID system and a communication device of the RFID system. <P>SOLUTION: In the RFID tag 2 and the antenna apparatus 3, the whole component containing antenna coils 4 and 7 is covered with a resin mold, and a plane facing the antenna apparatus 3 and the RFID tag 2 of a communication partner is formed with metal plates 60 and 80. Each of the antenna coils 4 and 7 is arranged in the mold resin so that coil planes 40 and 70 in each of which magnetic flux crosses are perpendicular to plate surfaces of the metal plates 60 and 80. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an RFID tag in which a component including an antenna coil is covered with a mold resin, an antenna device for the RFID system, and an RFID system communication device including a combination of the RFID tag and the antenna device.

  In recent years, a storage medium in which various information is written on a transported article is attached to a package management factory, a factory transport line, and the like, and the reader / writer performs wireless communication with the storage medium to store data. An RFID system that reads and writes information in a contactless manner with respect to a medium has been introduced (for example, see Patent Document 1). A storage medium attached to an article to be conveyed is referred to as an “RFID tag” or a “contactless IC tag”, and includes a component including an antenna coil for communication and an IC chip including a semiconductor memory.

Japanese Patent Laying-Open No. 2005-063081

  FIG. 11 shows an example in which the RFID system is introduced into a factory transport line. The RFID tag 100 is attached to a pallet 105 for conveying an article, and moves on the production line together with the article 104 to be conveyed. The reader / writer 101 has an antenna device 102 for communicating with the RFID tag 100 and a controller 103 for controlling the operation of the antenna device 102. The antenna device 102 has a built-in antenna coil for communication. The antenna device 102 demodulates the electromagnetic wave received from the RFID tag 100 and the function of transmitting an electromagnetic wave including a predetermined command and power to the RFID tag 100 via the antenna coil. , And a function of retrieving response information for the command. The controller 103 communicates with the RFID tag 100 via the antenna device 102 and reads / writes information from / to the RFID tag 100.

  As shown in FIG. 12, the antenna coils 105 and 106 of the RFID tag 100 and the antenna device 102 are arranged so that their coil surfaces 110 and 111 can face each other. Here, the “coil surface” is a virtual plane determined by the circulation of the antenna coil, that is, a virtual plane where generated magnetic fluxes intersect. When the RFID tag 100 enters the communicable region of the antenna device 102, the magnetic flux 107 generated by the antenna coil 106 of the antenna device 102 is linked to the antenna coil 105 of the RFID tag 100, and electromagnetic induction occurs in the antenna coil 105 of the RFID tag 100. Induced electromotive force due to. In the RFID tag 100 having no internal power supply, the IC chip in the RFID tag 100 is activated by the induced electromotive force, and the antenna coil 105 of the RFID tag 100 and the antenna coil 106 of the antenna device 102 are electromagnetically coupled. Thus, communication between the RFID tag 100 and the antenna device 102 becomes possible.

  The RFID tag 100 and the antenna device 102 are entirely covered with mold resins 108 and 109 in order to protect components such as the antenna coils 105 and 106. However, the synthetic resin does not have sufficient strength against external impacts, and durability is a problem. For example, when the antenna device 102 is installed close to the transition path of the RFID tag 100 in order to reliably read and write data, if a pallet or transported article moving on the transport line moves due to vibration or the like, the RFID The tag 100 comes into contact with the antenna device 102, and the impact is caused to damage the respective molding resins 108 and 109, thereby damaging components such as the internal antenna coils 105 and 106. As a result, the RFID tag 100 and the antenna device 102 are broken. There is a fear.

  In addition, as shown in FIG. 13, the user uses a handy type reader / writer 112 (the antenna device and the controller are incorporated in the same casing, and the whole is similarly covered with the mold resin 113). When communicating with the RFID tag 100 by hand, the reader / writer 112 is brought into contact with the RFID tag 100 so that the reader / writer 112 is brought close to the RFID tag 100 so that the user can reliably read and write data. However, the impact may cause the mold resins 108 and 113 to break and damage internal components.

  The present invention has been made paying attention to the above-described problems, and provides an RFID tag having excellent impact resistance and durability and good communication performance, an antenna device for the RFID system, and a communication device for the RFID system The purpose is to do.

  The RFID tag according to the present invention is such that a part including an antenna coil is covered with a mold resin, a surface facing a communicating antenna device is formed of a metal plate, and magnetic flux crosses the antenna coil. The coil surface is disposed in the mold resin in a direction orthogonal to the plate surface of the metal plate.

  In the above-described configuration of the present invention, the “antenna coil” is typically a coil pattern that forms an antenna coil formed on a plate surface of a printed board by printing or the like. In this embodiment, the “coil surface” is a plate surface of the printed board on which the coil pattern is formed, and is an area surrounded by the coil pattern. The antenna coil may be formed by winding a copper wire, for example.

  According to the RFID tag configured as described above, the surface facing the antenna device is formed of a metal plate having a high mechanical strength, so that the surface facing the RFID tag of the antenna device contacts the metal plate. Even if an impact is applied from the outside, the mold resin is not broken by the impact and the antenna coil is not damaged. In addition, since the coil surface of the antenna coil is oriented in a direction perpendicular to the plate surface of the metal plate, the magnetic flux generated by the antenna coil does not go to the metal plate, but moves over the metal plate and acts outside. To communicate with the antenna device.

  An antenna device for an RFID system according to the present invention is such that a component including an antenna coil is covered with a mold resin, and a surface facing an RFID tag to be communicated is formed of a metal plate, and the antenna coil Are arranged in the mold resin so that the coil surface where the magnetic flux intersects is perpendicular to the plate surface of the metal plate.

  The “antenna coil” of the antenna device is also typically formed by printing a coil pattern constituting the antenna coil on the plate surface of the printed board, and the surface of the printed board on which the coil pattern is formed is “ Coil surface ".

  According to the antenna device for an RFID system having the above-described configuration, the surface facing the RFID tag is formed of a metal plate having high mechanical strength, so that the surface facing the antenna device of the RFID tag contacts the metal plate. Even if an impact is applied from the outside, the mold resin is not damaged by the impact and the antenna coil is not damaged. In addition, since the coil surface of the antenna coil is oriented in a direction perpendicular to the plate surface of the metal plate, the magnetic flux generated by the antenna coil does not go to the metal plate, but moves over the metal plate and acts outside. To communicate with the RFID tag.

  The “antenna device” includes a circuit for transmitting and receiving signals in addition to an antenna coil for communication with the RFID tag. In general, a controller separate from the antenna device performs signal transmission and reception operations. By controlling the antenna device, the antenna device communicates with the RFID tag to read / write information from / to the RFID tag. However, the antenna device may be integrated with the controller. Good.

In a preferred embodiment of the present invention, each metal plate of the RFID tag and the antenna device constitutes a part of an outer frame that covers the mold resin, and the outer frame is a pair of metals integrally connected to both ends of the metal plate. Has a frame. According to this embodiment, both ends of the metal plate are supported by a pair of metal frames and the strength thereof is increased, so that deformation and breakage are prevented even when a strong impact is applied from the outside, and the impact resistance and durability are improved. The property is further improved.
Each metal frame is typically disposed outside the mold resin, but may be configured to be disposed inside the mold resin.

In a preferred embodiment of the present invention, each of the pair of metal frames is positioned at a position not facing the coil surface of the antenna coil.
Here, the “position not facing the coil surface of the antenna coil” is a position along the coil surfaces on both sides of the antenna coil, in other words, a position where the generated magnetic flux does not act.
According to this embodiment, the magnetic flux generated in the RFID tag and the antenna coil of the antenna device is not affected by the presence of the metal frame.

The pair of metal frames can be positioned at a position facing the coil surface of the antenna coil and a diagonal position thereof instead of the above-described positions. Here, the “position facing the coil surface of the antenna coil” is a position above the coil surface of the antenna coil, in other words, a position where the generated magnetic flux acts. Therefore, in this case, it is desirable to set the width of the metal frame as small as possible so that the influence of the presence of the metal frame on the magnetic flux is minimized.
In addition, although a metal plate can obtain required strength by a pair (two) of metal frames, it is possible to increase the number of metal frames in order to obtain further strength.

In a preferred embodiment of the present invention, marks indicating the orientation of the coil surface of the antenna coil in the mold resin are represented on the surface of each metal plate or mold resin of the RFID tag and the antenna device.
According to this embodiment, the orientation of the coil surface of the antenna coil in the mold resin can be easily recognized by the marks shown on the surface of the RFID tag and the antenna device metal plate or the mold resin. There is no risk of disturbing the installation work, and there is no risk of poor installation.

  An RFID system communication device according to the present invention comprises a combination of an RFID tag having any one of the above-described configurations and an antenna device for an RFID system having any one of the above-described configurations, and the respective metal plates can face each other. When the RFID tag and the antenna device are arranged as described above, the coil surface of the antenna coil of the RFID tag and the coil surface of the antenna coil of the antenna device can communicate with each other, and the coil surface of the antenna coil of the RFID tag. It is possible to set a state in which communication is impossible, in which the coil surface of the antenna coil of the antenna device and the coil surface of the antenna device are perpendicular to each other.

In the RFID system communication device described above, when the RFID tag and the antenna device are installed so that the coil surfaces of the respective antenna coils face the same direction, the magnetic flux generated in the antenna coil of the antenna device gets over the metal plate of the antenna device. Furthermore, the metal plate of the RFID tag gets over and reaches the antenna coil of the RFID tag and is linked. The magnetic flux generated in the antenna coil of the RFID tag also gets over the metal plate of the RFID tag, and further gets over the metal plate of the antenna device, reaches the antenna coil of the antenna device, and is linked. As a result, the antenna coil of the RFID tag and the antenna coil of the antenna device are electromagnetically coupled, and data communication is possible between the antenna device and the RFID tag.
On the other hand, when the RFID tag and the antenna device are installed so that the coil surfaces of the respective antenna coils are oriented in a right angle direction, the magnetic flux generated in the antenna coil of the antenna device (or RFID tag) is the antenna coil of the RFID tag (or antenna device). The data communication between the RFID tag and the antenna device becomes impossible.

  In the RFID system communication device described above, even if the RFID tag and the antenna device face each other for any reason, the opposing surfaces are formed of a metal plate. As a result, the mold resin is not damaged and the internal antenna coil and other components are not damaged.

Furthermore, for articles that require communication with the antenna device for articles flowing on the transport line, the direction of the RFID tag is the same as the coil surface of the antenna coil of the antenna device. Thus, for those that do not require communication with the antenna device, communication is performed by setting the direction of the RFID tag so that the coil surface of the antenna coil faces the direction perpendicular to the coil surface of the antenna coil of the antenna device. It is possible to set only the RFID tag that needs to be in a state in which communication with the antenna device is possible, and it is possible to realize efficient communication processing.
Also, on the transport line, by installing the antenna device in a communicable direction or in an incommunicable direction, an area (communication region) for data communication between the antenna device and the RFID tag It is also possible to set a non-communication area (non-communication area).

  According to the present invention, since the surface facing the communication partner is formed by the metal plate, it is possible to prevent damage due to an impact from the outside of the RFID tag and the antenna device, and to improve the impact resistance and durability. In addition, each antenna coil built in the RFID tag and the antenna device has its coil surface oriented in a direction orthogonal to the plate surface of the metal plate, so the magnetic flux generated by the antenna coil gets over each metal plate and communicates with it. The presence of the metal plate does not hinder communication between the RFID tag and the antenna device.

  FIG. 1 shows the configuration and appearance of a communication device 1 of an RFID system according to an embodiment of the present invention. The communication device 1 in the illustrated example includes, for example, an RFID tag 2 attached to an article or a pallet conveyed on a production line of a factory, and an RFID tag that is installed at a proper position along the transition path of the RFID tag 2 and passes through the installation position. 2 and an antenna device 3 for communicating various data.

  The RFID tag 2 has a configuration in which components such as a communication antenna coil 4 (shown in FIG. 2) and an IC chip (not shown) are entirely covered with a mold resin such as PPS resin. It is composed of a columnar molded resin molded body (hereinafter referred to as “main body portion”) 20 and a metal outer frame 6 that covers the outside of the main body portion 20.

As shown in FIG. 2, the antenna coil 4 of the RFID tag 2 is formed by printing a rectangular spiral coil pattern 50 on one plate surface of a rectangular printed board 5. A region on the plate surface of the printed circuit board 5 surrounded by the coil pattern 50 is a coil surface 40, and magnetic flux generated by the antenna coil 4 intersects the coil surface 40. As shown in FIGS. 3 and 4, the printed circuit board 5 has a main body portion in a direction perpendicular to a front end surface 20 a of the main body portion 20 and a plate surface 64 of a metal plate 60 to be described later on which the front end surface 20 a is superimposed. 20 is arranged. In the following description, the RFID tag 2 and the antenna device 3 are referred to as “front” on the opposite side and “rear” on the opposite side.
For example, the RFID tag 2 is usually attached to a pallet for article conveyance so that the antenna coil 4 is horizontal.

  A circuit pattern (not shown) that is electrically connected to the coil pattern 40 is printed on the surface of the printed board 5, and an IC chip (not shown) is mounted on the circuit pattern. The IC chip includes a CPU, a memory, a communication circuit, and the like, and exchanges various data with the antenna device 3 via the antenna coil 4. The RFID tag 2 does not have a built-in power supply, and uses an induced electromotive force generated when the magnetic flux from the antenna device 3 is linked to the antenna coil 4 as a power supply.

  The outer frame 6 is made of, for example, stainless steel, and includes a metal plate 60 and a metal ring 61 opposed to each other as shown in FIGS. 1 to 4, and a pair of metal frames 62A and 62B opposed to the left and right. The metal plate 60 and the metal ring 61 are integrated via the metal frames 62A and 62B.

  The metal plate 60 is a disc having a diameter larger than that of the main body 20, and the front end surface 20 a of the main body 20 is in close contact with the inner plate surface 64. It should be noted that the plate surface 64 of the metal plate 60 and the front end surface 20a of the main body portion 20 may be fixed together by an adhesive or the like. The main body 20 is fixed to the frame 6 so as not to idle. When the front end surface 20a of the main body 20 is brought into close contact with the plate surface 64 of the metal plate 60, the coil surface 40 of the antenna coil 4 is oriented perpendicularly (upward in the drawing) to the plate surface 64 of the metal plate 60.

  The pair of metal frames 62 </ b> A and 62 </ b> B are integrally connected to the diagonal position of the outer peripheral portion of the metal plate 60 and the rear end to the diagonal position of the metal ring 61, respectively, and the coil surface 40 of the antenna coil 4. Are positioned at positions that are not opposite to each other, that is, positions along the coil surfaces 40 on both sides of the antenna coil 4. The magnetic flux generated in the antenna coil 4 hardly acts on this position, and the magnetic flux generated in the antenna coil 4 is not affected at all even if the metal frames 62A and 62B exist at this position. The inner surfaces of the metal frames 62 </ b> A and 62 </ b> B are in surface contact with the outer peripheral surface of the main body 20.

The metal ring 61 has an inner diameter that matches the outer diameter of the main body 20, and the outer peripheral surface of the main body 20 is fitted on the inner peripheral surface. A circumferential groove 21 shown in FIG. 1 is formed on the outer peripheral portion of the rear end surface 20b of the main body portion 20, and the diagonal position of the circumferential groove 21 is the angular position where the metal frames 62A and 62B are located. Notch grooves 22 and 23 are formed. A retaining ring 24 is fitted into the circumferential groove 21, and protrusions 25 and 26 provided at corresponding portions of the retaining ring 24 are engaged with the notch grooves 22 and 23. The retaining ring 24 is fixed to the inner peripheral surface of the metal ring 61 with an adhesive. The retaining ring 24 prevents the main body portion 20 from coming out of the outer frame 6, and the main body portion 20 with respect to the outer frame 6. Prevents the coil surface 40 and the metal frames 62A and 62B from being misaligned.
The main body portion 20 is pushed into the inner side of the outer frame 6 having the above-described configuration from the metal ring 61 side and the front end surface 20a is pressed against the plate surface 64 of the metal plate 60, and then the retaining ring 24 is placed inside the metal ring 61. The main body 20 is fixed in the outer frame 6 by fitting.

  In the RFID tag 2 of this embodiment, the antenna coil 4 built in the outer peripheral surface of the main body 20 and the metal plate 60 of the outer frame 6 and the surfaces of the metal frames 62A and 62B are provided as shown in FIGS. A plurality of marks A1, A2, B1, and B2 are represented by printing or the like so that the direction of the coil surface 40 and the direction of the magnetic flux crossing the coil surface 40 can be seen from the outside.

  Two types of marks A1 and B1 are shown on the surface of the metal plate 60 (FIG. 4). One mark A <b> 1 is one long thick line and represents the position and the width direction of the coil surface 40 of the antenna coil 4. This one long thick line crosses the surface of the metal plate 60 over the entire length of the diameter line. The other mark B <b> 1 is two short thick lines and represents a direction orthogonal to the coil surface 40 of the antenna coil 4. These two short thick lines are respectively shown at diagonal positions on the outer peripheral portion of the metal plate 60.

A mark A2 is shown in the vicinity of the metal plate 60 on the surface of each of the pair of metal frames 62A and 62B (FIGS. 1 to 3). This mark A2 is one short thick line, and represents the position and length direction of the coil surface 40 of the antenna coil 4.
A mark B2 is shown near the metal plate 60 on the outer peripheral surface of the main body 20 (FIGS. 1 and 3). This mark B <b> 2 is two short thick lines and represents a direction orthogonal to the coil surface 40. These two short thick lines are respectively shown at diagonal positions on the outer peripheral surface of the main body 20. The direction of the magnetic flux crossing the coil surface 40 can be grasped by the above-described marks B1 and B2.

  Returning to FIG. 1, the antenna device 3 includes all parts such as a communication antenna coil 7 (shown in FIG. 2), an IC chip (not shown) constituting a transmission circuit, a reception circuit, and a control circuit. For example, it is configured to be covered with a mold resin such as PPS resin, and includes a cylindrical mold resin molded body (hereinafter referred to as “main body portion”) 30 and an outer frame 8 that covers the outer side of the main body portion 30. Has been. The antenna device 3 is connected to a controller (not shown) by a cable 9 including a power supply line and a signal line. The controller supplies power to the antenna device 3 via the cable 9 and outputs various command signals. Further, the controller takes in a response signal from the RFID tag 2 to the command signal from the antenna device 3 via the cable 9.

As shown in FIG. 2, the antenna coil 7 of the antenna device 3 is formed by printing a rectangular spiral coil pattern 71 on one plate surface of a rectangular printed board 10. A region on the plate surface of the printed circuit board 10 surrounded by the coil pattern 71 is a coil surface 70, and magnetic flux generated by the antenna coil 7 crosses the coil surface 70. As shown in FIGS. 5 and 6, the printed board 10 has a main body portion in a direction orthogonal to a front end surface 30 a of the main body portion 30 and a plate surface 84 of a metal plate 80 to be described later on which the front end surface 30 a is superimposed. 30. On the printed circuit board 10, components such as an IC chip constituting a transmission circuit, a reception circuit, and a control circuit are also mounted.
The antenna device 3 is installed at an appropriate position along the transition path of the RFID tag 2 so that the antenna coil 7 is horizontal. Note that if the antenna device 3 is installed so that the antenna coil 7 is vertical, it is possible to set a non-communication area in which data communication with the RFID tag 2 is not performed.

  The outer frame 8 is made of, for example, stainless steel, and, as shown in FIGS. 1, 2, 5, and 6, a metal plate 80 and a metal cylinder 81 opposed to the front and rear, and a pair of metal frames 82A opposed to the left and right. , 82B, and the metal plate 80 and the metal cylinder 81 are integrated via the metal frames 82A, 82B.

  The metal plate 80 is a disc having a diameter larger than that of the main body 30, and the front end surface 30 a of the main body 30 is in close contact with the inner plate surface 84. Note that the plate surface 84 of the metal plate 80 and the front end surface 30a of the main body 30 may be fixed together by an adhesive or the like, but in this embodiment, the retaining ring 24 of the RFID tag 2 is integrated. The main body 30 is fixed to the outer frame 8 so as not to idle by a retaining ring (not shown) having the same configuration as in FIG. When the front end surface 30a of the main body 30 is brought into close contact with the plate surface 84 of the metal plate 80, the coil surface 70 of the antenna coil 7 is oriented in a direction (upward in the drawing) perpendicular to the plate surface 84 of the metal plate 80.

  The pair of metal frames 82 </ b> A and 82 </ b> B are integrally connected to the diagonal position of the outer periphery of the metal plate 80 and the rear end to the diagonal position of the metal cylinder 81, respectively. Are positioned at positions that are not opposed to each other, that is, positions along the coil surfaces 70 on both sides of the antenna coil 7. The magnetic flux generated in the antenna coil 7 hardly acts on this position, and the magnetic flux generated in the antenna coil 7 is not affected at all even if the metal frames 82A and 82B exist at this position. The inner surfaces of the metal frames 82A and 82B are in surface contact with the outer peripheral surface of the main body 30.

The metal cylinder 81 has an inner diameter that matches the outer diameter of the main body 30, and the outer peripheral surface of the main body 30 is fitted on the inner peripheral surface. On the outer peripheral surface of the metal cylinder 81, a thread 85 for attaching and fixing the antenna device 3 to an appropriate installation location is formed. A circumferential groove (not shown) is formed on the outer peripheral portion of the rear end surface of the main body 30, and a retaining ring that serves as both a retaining stopper and a rotation stopper is fitted in the circumferential groove. The configuration of the circumferential groove and the retaining ring is the same as that of the RFID tag 2, and illustration and description thereof are omitted here.
The main body 30 is pushed into the inside of the outer frame 8 having the above-described configuration from the side of the metal cylinder 81 and the front end surface 30a is pressed against the plate surface 84 of the metal plate 80, and then a retaining ring is fitted inside the metal cylinder 81. The main body 30 is fixed in the outer frame 8 by wearing.

  As shown in FIGS. 1, 2, 5, and 6, the outer peripheral surface of the main body 30 of the antenna device 3 and the metal plate 80 of the outer frame 8 and the surfaces of the metal frames 82A and 82B are built in. A plurality of marks C1, C2, D1, and D2 are represented by printing or the like so that the direction of the coil surface 70 of the antenna coil 7 to be rotated and the direction of the magnetic flux crossing the coil surface 70 can be seen from the outside.

  Two types of marks C1 and D1 are shown on the surface of the metal plate 80 (FIGS. 1, 2, and 6). One mark C <b> 1 is one long thick line and represents the position and the width direction of the coil surface 70 of the antenna coil 7. This one long thick line crosses the surface of the metal plate 80 over the entire length of the diameter line. The other mark D <b> 1 is two short thick lines and represents a direction orthogonal to the coil surface 70 of the antenna coil 7. These two short bold lines are respectively shown at diagonal positions on the outer peripheral portion of the metal plate 80.

A mark C2 is shown in the vicinity of the metal plate 80 on the surface of each of the pair of metal frames 82A and 82B (FIGS. 1, 2, and 5). This mark C2 is one short thick line, and represents the position and the length direction of the coil surface 70 of the antenna coil 7.
A mark D2 is shown in the vicinity of the metal plate 80 on the outer peripheral surface of the main body 30 (FIGS. 1 and 5). This mark D <b> 2 is two short thick lines and represents a direction orthogonal to the coil surface 70. These two short bold lines are respectively shown at diagonal positions on the outer peripheral surface of the main body 30. The direction of the magnetic flux crossing the coil surface 70 can be grasped by the above-described marks D1 and D2.

7 and 8 show an RFID system communication apparatus 1 according to another embodiment of the present invention. The RFID tag 2 in the illustrated example has a position where the pair of metal frames 62A and 62B constituting the outer frame 6 face the coil surface 40 of the antenna coil 4, that is, an upper position of the antenna coil 4 with respect to the coil surface 40 and its position. They are positioned at diagonal positions.
Similarly, in the antenna device 3, the pair of metal frames 82 </ b> A and 82 </ b> B constituting the frame 8 are opposed to the coil surface 70 of the antenna coil 7, that is, the upper position of the antenna coil 7 with respect to the coil surface 70 and the pair. It is positioned at each angular position.

Also in this embodiment, the outer peripheral surfaces of the body portions 20 and 30 of the RFID tag 2 and the antenna device 3, the metal plates 60 and 80 of the outer frames 6 and 8, and the surfaces of the metal frames 62A, 62B, 82A and 82B, A plurality of marks A1, A2, B1, B2, C1, C2, D1 so that the direction of the coil surfaces 40, 70 of the built-in antenna coils 4, 7 and the direction of the magnetic flux crossing the coil surfaces 40, 70 can be seen from the outside. , D2 are displayed by printing or the like.
The positions and other configurations of the marks A1, A2, B1, B2, C1, C2, D1, and D2 are the same as those in the embodiment shown in FIGS. Detailed description will be omitted.

  When the RFID tag 2 enters the communication area with the antenna device 3 and communicates with the antenna device 3 in the communication device 1 of the RFID system configured as described above, as shown in FIGS. 2 and 9, the RFID tag Since the coil surface 40 of the antenna coil 4 and the coil surface 70 of the antenna coil 7 of the antenna device 3 face the same direction, the magnetic flux 11 generated in the antenna coil 7 of the antenna device 3 is the metal of the antenna device 3. Over the plate 80, and further over the metal plate 60 of the RFID tag 2 to reach the antenna coil 4 and interlink. Thereby, the induced electromotive force of the antenna coil 4 is supplied to the RFID tag 2 to operate the IC chip, and the antenna coil 4 of the RFID tag 2 and the antenna coil 7 of the antenna device 3 are electromagnetically coupled, Data can be exchanged between the antenna device 3 and the RFID tag 2.

  On the other hand, as shown in FIG. 10, when the coil surface 40 of the antenna coil 4 of the RFID tag 2 faces a right angle with respect to the coil surface 70 of the antenna coil 7 of the antenna device 3, the antenna coil 7 of the antenna device 3 is. The generated magnetic flux does not interlink with the antenna coil 4 of the RFID tag 2, and communication between the RFID tag 2 and the antenna device 3 becomes impossible.

  According to the communication device 1 of the RFID system configured as described above, the opposing surfaces of the RFID tag 2 and the antenna device 3 are formed by the metal plates 60 and 80, so that the opposing surfaces of the antenna device 3 and the RFID tag 2 are Even if an impact is applied by contact or the like, the main body portions 20 and 30 are not damaged by the impact. In addition, the metal plates 60 and 80 are reinforced by the metal frames 62A, 62B, 82A, and 82B, respectively, so that the strength thereof is further enhanced, so that deformation and breakage of the RFID tag 2 and the antenna device 3 are completely prevented. The

  Further, for an article that needs to communicate with the antenna device 3 with respect to an article flowing on the transport line, the direction of the RFID tag 2 is such that the coil surface 40 of the antenna coil 4 is the coil of the antenna coil 7 of the antenna device 3. For those that do not require communication with the antenna device 3 so as to face the same direction as the surface 70 (see FIG. 2), the direction of the RFID tag 2 is such that the coil surface 40 of the antenna coil 4 is the antenna coil 7 of the antenna device 3. By setting each so as to face the coil surface 70 at right angles (see FIG. 10), only the RFID tag 2 that needs to be communicated can be set in a state in which communication with the antenna device 3 is possible. Processing efficiency can be improved.

1 is a perspective view showing an appearance of a communication device for an RFID system according to an embodiment of the present invention. FIG. 2 is a perspective view of the embodiment of FIG. 1 in which the RFID tag and the antenna resin of the antenna device are removed. It is a side view of the RFID tag of the Example of FIG. It is a front view of the RFID tag of the Example of FIG. It is a side view of the antenna apparatus of the Example of FIG. It is a front view of the antenna apparatus of the Example of FIG. It is a perspective view which shows the external appearance of the communication apparatus of the RFID system which is another Example of this invention. FIG. 8 is a perspective view of the embodiment of FIG. 7 with the RFID tag and antenna device mold resin removed. It is explanatory drawing which represented typically the magnetic flux which acts between an RFID tag and an antenna apparatus. It is a perspective view which shows the internal structure of an RFID tag and an antenna device when communication with an RFID tag and an antenna device becomes impossible. It is explanatory drawing which shows the outline | summary of a RFID system. It is explanatory drawing which represented typically the magnetic flux which acts between the RFID tag and antenna apparatus of a prior art example. It is explanatory drawing which shows the RFID system using the handy type reader / writer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Communication apparatus of RFID system 2 RFID tag 3 Antenna apparatus for RFID system 4 Antenna coil of RFID tag 7 Antenna coil of antenna apparatus 20 Main part of RFID tag 30 Main part of antenna apparatus 60 Metal plate 61 Metal ring 62A, 62B Metal Frame 80 Metal plate 81 Metal ring 82A, 82B Metal frame

Claims (9)

  In an RFID tag in which a component including an antenna coil is covered with a mold resin, a surface facing an antenna device to be communicated is formed of a metal plate, and the antenna coil has a coil surface where a magnetic flux intersects the metal plate. An RFID tag arranged in a mold resin in a direction orthogonal to the plate surface.   2. The RFID tag according to claim 1, wherein the metal plate constitutes a part of an outer frame that covers the mold resin, and the outer frame includes a pair of metal frames that are integrally connected to both ends of the metal plate.   The RFIF tag according to claim 2, wherein each of the pair of metal frames is positioned at a position not facing the coil surface of the antenna coil.   The RFID tag according to claim 1, wherein a mark indicating a direction of a coil surface of an antenna coil in the mold resin is represented on a surface of the metal plate or the mold resin.   In an antenna device for an RFID system in which a component including an antenna coil is covered with a mold resin, a surface facing an RFID tag to be communicated is formed of a metal plate, and the antenna coil has a coil surface where magnetic flux intersects. An antenna device for an RFID system, which is arranged in a mold resin in a direction orthogonal to the plate surface of the metal plate.   6. The RFID tag according to claim 5, wherein the metal plate constitutes a part of an outer frame that covers the mold resin, and the outer frame includes a pair of metal frames integrally connected to both ends of the metal plate.   The antenna device for an RFID system according to claim 6, wherein each of the pair of metal frames is positioned at a position not facing the coil surface of the antenna coil.   The antenna device for an RFID system according to claim 5, wherein a mark indicating a direction of a coil surface of an antenna coil in the mold resin is represented on a surface of the metal plate or the mold resin. A combination of the RFID tag according to any one of claims 1 to 4 and the antenna device for an RFID system according to any one of claims 5 to 8,
When the RFID tag and the antenna device are arranged so that the respective metal plates can face each other, the coil surface of the RFID tag antenna coil and the antenna coil coil surface of the antenna device can communicate in the same direction, and An RFID system communication device capable of setting an incommunicable state in which a coil surface of an antenna coil of an RFID tag and a coil surface of an antenna coil of an antenna device are perpendicular to each other.

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