Expansion antenna device

Abstract

To provide an expansion antenna device in which the cost of a connection line between a first coil and a second coil is reduced, resistance to bending, etc., is obtained, and routing is easy.SOLUTION: An expansion antenna device 50 transmits an induced current signal generated at a first coil 51a as a result of electromagnetic induction with respect to a transmission source coil 11, from a second coil 52a connected to the first coil via a connection line, to a transmission destination coil 41 as a result of electromagnetic induction. One end side of a winding wire of the first coil and one end side of a winding wire of the second coil are connected via a single connection line 53. The other end side 51c of the winding wire of the first coil and the other end side 52c of the winding wire of the second coil are both open.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an extended antenna device. [Background technology]

[0002] Conventionally, an extended antenna device is known in which an induced current signal generated in a first coil by electromagnetic induction between the first coil and a source coil is transmitted from a second coil connected to the first coil via a connecting wire to a destination coil by electromagnetic induction.

[0003] Patent Document 1 discloses a bridge antenna (extension antenna device) including two RF antenna coils that are spaced apart but connected to each other by a conductor. One of the two RF antenna coils (second coil) is located close to a coil in an RFID tag (destination coil), and the other (first coil) is located close to a reader coil (source coil). An electromagnetic carrier signal generated by the reader coil is transmitted to the other RF antenna coil, then transmitted through the conductor to the one RF antenna coil, and then transmitted from the one RF antenna coil to the RFID tag coil.

[0004] Furthermore, Patent Document 2 discloses a non-contact extension cord (extension antenna device) for supplying power to a power receiving device that is spaced apart from a power supply device. The non-contact extension cord has a relay power receiving coil (first coil) and a relay power transmitting coil (second coil), with both ends of the windings of each coil connected to each other. The relay power receiving coil is disposed opposite to the power transmitting coil (source coil) of the power supply device so as to be magnetically coupled, and outputs an induced electromotive force to the relay power transmitting coil by intersecting with an alternating magnetic field generated by the power transmitting coil. The relay power transmitting coil is disposed opposite to the power receiving coil (destination coil) of the power receiving device so as to be magnetically coupled, and an induced electromotive force is generated in the power receiving coil by intersecting with an alternating magnetic field generated by the relay power transmitting coil. Summary of the Invention [Problem to be solved by the invention]

[0005] However, conventional extension antenna devices have had problems such as the need for two connecting wires between the first coil and the second coil, which makes them expensive, and they are difficult to route because they are weak against bending, etc. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the present invention provides an extended antenna device that transmits an induced current signal generated in a first coil by electromagnetic induction between a source coil and the first coil from a second coil connected to the first coil via a connecting wire to a destination coil by electromagnetic induction, wherein one end of the winding of the first coil and one end of the winding of the second coil are connected to each other by a single connecting wire, and the other end of the winding of the first coil and the other end of the winding of the second coil are both open. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an extension antenna device in which the connecting wire connecting the first coil and the second coil is inexpensive, and is resistant to bending and the like, making it easy to route. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is an explanatory diagram showing a usage mode in which the extension antenna device is not used in the RFID tag reading system according to the first embodiment. [Figure 2] FIG. 2 is an explanatory diagram showing an example of a usage mode in which an extension antenna device is used in the RFID tag reading system according to the first embodiment. [Figure 3] FIG. 3 is an explanatory diagram showing an equivalent circuit of the extension antenna device. [Figure 4] 1A is a plan view showing the internal structure of an extended antenna device in use example 1. FIG. 1B is a side view showing the same extended antenna device. FIG. 1C is a side view showing the same extended antenna device when the angle of the second coil part is changed from the angle shown in FIG. 1B. [Figure 5]10 is an explanatory diagram illustrating the use of the extension antenna device attached to a smartphone. FIG. [Figure 6] (a) is an image of a logistics center, (b) is an image of a manufacturing factory, and (c) is an image of a medical or nursing care facility. [Figure 7] An illustration showing how the RFID tag on a medicine pack is read using the same extension antenna device attached to a smartphone worn on the user's wrist. [Figure 8] (a) is an illustration showing a name tag with an RFID tag attached to a user's breast pocket. (b) is an explanatory diagram showing how the RFID tag on a name tag attached to a user's breast pocket can be directly read by a smartphone. [Figure 9] FIG. 10 is a perspective view showing an extension antenna device in a second usage example. [Figure 10] FIG. 10 is an explanatory diagram showing an RFID tag reading system using an extension antenna device in Usage Example 3. [Figure 11] (a) is an exploded view of the three coil units that make up the extension antenna device, and (b) is an explanatory diagram showing the three coil units assembled together. [Figure 12] FIG. 10 is an explanatory diagram showing an RFID tag reading system using an extension antenna device in Usage Example 4. [Figure 13] FIG. 10 is an explanatory diagram showing a comparative example of a configuration in which four coils are connected in series with a single connection line. [Figure 14] FIG. 10 is an explanatory diagram showing an example in which the extension antenna device is mounted on a robot arm in Usage Example 5. [Figure 15] FIG. 13 is an explanatory diagram showing an RFID tag reading system using an extension antenna device in Usage Example 6. [Figure 16] FIG. 2 is an explanatory diagram showing the configuration of the extension antenna device. [Figure 17] FIG. 10 is an explanatory diagram showing an RFID tag reading system using an extension antenna device according to a first modification. [Figure 18] FIG. 13 is an explanatory diagram showing an RFID tag reading system using an extension antenna device in Usage Example 7. [Figure 19] FIG. 13 is an explanatory diagram of an example in which the extension antenna device in Usage Example 8 is applied to a storage box equipped with an RFID tag. [Figure 20] FIG. 13 is an explanatory diagram showing how information from an RFID tag on a storage box in Usage Example 8 is read by reader antennas placed in three different positions. [Figure 21] FIG. 10 is an explanatory diagram showing an example in which the extension antenna device of Use Example 8 is applied to extend the reader antenna. [Figure 22] FIG. 10 is an explanatory diagram showing an RFID tag reading system using an extension antenna device according to a second modification. [Figure 23] FIG. 10 is an explanatory diagram showing the configuration of a coil switch provided in an extension antenna device of Modification 2. [Figure 24] 10 is a flowchart showing a procedure for reading information from an RFID tag using an extension antenna device according to a second modification. [Figure 25] FIG. 13 is an explanatory diagram showing an RFID tag reading system using an extension antenna device in Usage Example 9. [Figure 26] FIG. 13 is a perspective view showing a dispensing box set on a medication tray in Example 9 of Use. [Figure 27] FIG. 10 is an explanatory diagram showing an example in which information read from an RFID tag attached to a medicine pack in a dispensing box set on the same medication tray is used to control a robot arm (picking robot) in Usage Example 9. [Figure 28] FIG. 10 is an explanatory diagram showing a storage system for storing chemicals and the like that are subject to management obligations in use example 10. [Figure 29] FIG. 2 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device used in the storage system. [Figure 30] FIG. 10 is an explanatory diagram showing an example in which a weight sensor is installed at each medicine placement location of a storage case in the storage cabinet system. [Figure 31] FIG. 19 is an explanatory diagram showing an RFID tag reading system using an extension antenna device in Usage Example 11. [Figure 32]FIG. 10 is an explanatory diagram showing a usage state in which an extension antenna device is not used in the wireless power supply system according to the second embodiment. [Figure 33] FIG. 10 is an explanatory diagram showing an example of a usage mode in which an extension antenna device is used in the wireless power supply system. [Figure 34] FIG. 12 is a perspective view showing an extension antenna device in a twelfth example of use. [Figure 35] FIG. 13 is an explanatory diagram showing an example of a wireless power supply system that charges a smartphone using an extension antenna device in Usage Example 13. [Figure 36] FIG. 2 is an explanatory diagram showing the configuration of the extension antenna device. [Figure 37] FIG. 19 is an explanatory diagram showing an example of a wireless power supply system that charges an electric vehicle using an extension antenna device in Use Example 14. [Figure 38] FIG. 15 is an explanatory diagram showing an example of a wireless power supply system that charges an electric vehicle using an extension antenna device in Usage Example 15. [Figure 39] FIG. 16 is an explanatory diagram showing an example of a wireless power supply system that charges an electric vehicle using an extension antenna device in Use Example 16. [Figure 40] 17(a) to 17(c) are explanatory diagrams showing an RFID tag reading system using an extended antenna device in Example 17 of the present invention. [Figure 41] FIG. 2 is an explanatory diagram showing the configuration of one coil unit that constitutes the extension antenna device. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Embodiment 1] Hereinafter, an embodiment (hereinafter, this embodiment will be referred to as "Embodiment 1") in which the present invention is applied to an extension antenna device that extends the communication area of ​​an RFID reader that reads RFID tags will be described. Note that "expanding" the communication area here means enabling communication at locations farther away than the communication area of ​​the RFID reader, and includes expanding the size of the communication area or moving the communication area to a location farther away from the RFID reader.

[0010] FIG. 1 is an explanatory diagram showing a usage mode in which an extension antenna device is not used in the RFID tag reading system 1 according to the first embodiment. The RFID tag reading system of the first embodiment includes a reader antenna 10, an RFID reader 20, and an information processing device 30 such as a PC (personal computer). The RFID reader 20 is connected to the information processing device 30 by a communication cable 31.

[0011] Reference numeral 40 denotes, for example, an HF band RFID tag having a built-in NFC (Near Field Communication) chip 42. The RFID reader 20 can read information stored in the NFC chip 42 of the RFID tag 40 by communicating with the RFID tag 40 via the reader antenna 10. The RFID reader 20 may also have a writer function for writing information to the NFC chip 42 of the RFID tag 40. The communication partner of the RFID reader 20 is not limited to the RFID tag 40, and the same applies to devices (such as mobile communication terminals such as smartphones) equipped with a similar NFC chip.

[0012] The RFID tag 40 has a circuit configuration in which a parallel resonant circuit of a capacitor and a coil 41 (a destination coil or a source coil) is connected to a transmitting / receiving terminal of an NFC chip 42. In the RFID tag 40, a signal of a predetermined frequency (here, an HF band: 13.56 MHz) transmitted from the RFID reader 20 via the reader antenna 10 is received by the coil 41 of the parallel resonant circuit and transmitted to the NFC chip. In the RFID tag 40, the signal of the predetermined frequency from the NFC chip 42 is transmitted from the coil 41 of the parallel resonant circuit to the RFID reader 20 via the reader antenna 10.

[0013] The reader antenna 10 is connected to the RFID reader 20 by a communication cable 21. More specifically, the reader antenna 10 has a circuit configuration in which a parallel resonant circuit of a capacitor and a coil 11 (a source coil or a destination coil) is connected to a transmitting / receiving terminal of the RFID reader 20. In the reader antenna 10, a signal of a predetermined frequency transmitted from the RFID reader 20 is transmitted from the coil 11 of the parallel resonant circuit to the RFID tag 40. In addition, in the reader antenna 10, the signal of the predetermined frequency transmitted from the RFID tag 40 is received by the coil 11 of the parallel resonant circuit and transmitted to the RFID reader 20.

[0014] A signal of a predetermined frequency output from the RFID reader 20 is parallel-resonated (tuned) in the parallel resonant circuit of the reader antenna 10, causing a resonant current to flow through the coil 11 in the parallel resonant circuit, and this resonant current generates a magnetic field M, as shown by the magnetic field lines in the figure, in the coil 11. When the RFID tag 40 is brought close to the reader antenna 10 in this state, the magnetic field M generated in the coil 11 of the reader antenna 10 passes through the coil 41 of the RFID tag 40, causing an induced current to flow in the coil 41 of the RFID tag 40, and a signal of this induced current is input to the transmitting / receiving terminal of the NFC chip 42.

[0015] In this way, when an induced current signal is input to NFC chip 42 of RFID tag 40, NFC chip 42 outputs stored information (such as RFID identification information) to the transmitting / receiving terminal as a signal of a predetermined frequency. The signal output from NFC chip 42 is parallel-resonated (tuned) in the parallel resonant circuit of RFID tag 40, causing a resonant current to flow in coil 41 in the parallel resonant circuit, and this resonant current generates a magnetic field M in coil 41. As a result, the magnetic field M generated in coil 41 of RFID tag 40 passes through coil 11 of reader antenna 10, and an induced current flows in coil 11 of reader antenna 10. As a result, the induced current signal is transmitted to RFID reader 20.

[0016] FIG. 2 is an explanatory diagram showing an example of a usage mode in which the extension antenna device 50 according to the present invention is used in the RFID tag reading system 1 according to the first embodiment. The extension antenna device 50 of this embodiment has a coil unit including a first coil section 51 arranged close to the reader antenna 10 and a second coil section 52 arranged at a location spaced apart from the first coil section 51 (i.e., at a location spaced apart from the reader antenna 10).

[0017] The first coil section 51 has a first coil 51a formed by winding a conductor wire such as a copper wire around a core 51b. The second coil section 52 also has a second coil 52a formed by winding a conductor wire such as a copper wire around a core 52b. The number of turns of the coils 51a, 52a of the first coil section 51 and the second coil section 52 are set so as to resonate (tune) with the frequency (HF band: 13.56 MHz) used by the reader antenna 10 and the RFID tag 40. The core may be made of plastic, paper, or a magnetic material.

[0018] In the extended antenna device 50 of this embodiment, the first coil 51a of the first coil section 51 and the second coil 52a of the second coil section 52 are connected by a single connecting wire 53. Specifically, one end of the winding of the first coil 51a and one end of the winding of the second coil 52a are connected to each other by the single connecting wire 53, and the other end 51c of the winding of the first coil 51a and the other end 52c of the winding of the second coil 52a are both open.

[0019] Such an extended antenna device 50 can be manufactured by a simple manufacturing method in which a single conductor wire is wound around core 51b of first coil portion 51 to form first coil 51a, and the conductor wire is then extended and wound around core 52b of second coil portion 52 to form second coil 52a. In this case, single connection wire 53 is the conductor wire itself in an uncoated state, but it may also be a connection wire 53 in which the periphery of the conductor wire is coated with an insulating layer as long as it is an unshielded wire that is not shielded.

[0020] FIG. 3 is an explanatory diagram showing an equivalent circuit of the extension antenna device 50 in this embodiment. When the extension antenna device 50 of this embodiment is used, a magnetic field M generated in the coil 11 (transmitter coil) of the reader antenna 10 by a signal of a predetermined frequency output from the RFID reader 20 generates an induced current signal i by electromagnetic induction in the first coil 51a of the first coil unit 51 arranged close to the reader antenna 10. This induced current signal i flows into the second coil 52a of the second coil unit 52 connected to the first coil 51a via a connection wire 53. As a result, a magnetic field M corresponding to the induced current signal i corresponding to the signal from the RFID reader 20 is generated in the second coil 52a of the second coil unit 52.

[0021] In this state, when the RFID tag 40 is brought close to the second coil section 52 of the extension antenna device 50, the magnetic field M generated by the second coil 52a of the second coil section 52 passes through the coil 41 (destination coil) of the RFID tag 40, causing an induced current i to flow in the coil 41 of the RFID tag 40. As a result, a signal of the induced current i is input to the transmitting / receiving terminal of the NFC chip 42, and the signal from the RFID reader 20 is transmitted.

[0022] Similarly, the signal output from the NFC chip 42 is transmitted by electromagnetic induction from the coil 41 of the RFID tag 40 to the second coil 52a of the second coil unit 52 of the extension antenna device 50. As a result, an induced current signal i generated in the second coil 52a flows into the first coil 51a of the first coil unit 51 via the connection line 53, and a magnetic field M corresponding to the induced current signal i corresponding to the signal from the NFC chip 42 is generated in the first coil 51a. As a result, the magnetic field M generated in the first coil 51a passes through the coil 11 of the reader antenna 10, and an induced current i flows in the coil 11 of the reader antenna 10, and a signal of the induced current i is transmitted to the RFID reader 20.

[0023] According to this embodiment, by using the extension antenna device 50, it is possible to read information from the RFID tag 40 even at a location far away from the reader antenna 10 connected to the RFID reader 20. Therefore, it is possible to extend the communication area of ​​the reader antenna 10 of the RFID reader 20.

[0024] In conventional extended antenna devices, the connecting wire connecting the first coil and the second coil has a loop structure in which both ends of the windings of each coil are connected to each other. Therefore, the first coil and the second coil are connected by at least two connecting wires. In this case, the induced current signal flowing through the two connecting wires is a relatively high-frequency signal, so interference between the connecting wires needs to be suppressed, and shielded wires such as coaxial cables are used for each connecting wire. As a result, the connecting wires connecting the first coil and the second coil are expensive and difficult to route due to their fragile resistance to bending, etc.

[0025] According to the extension antenna device 50 of this embodiment, as described above, the connection line 53 connecting the first coil 51a and the second coil 52a is a single connection line, and there is no need to suppress interference between the connection lines. Therefore, there is no need to use a shielded wire such as a coaxial cable as in conventional extension antenna devices, and it is possible to use an inexpensive connection line 53 that is resistant to bending and easy to route. In this embodiment, the windings (conductor wires) of the first coil 51a and the second coil 52a themselves are used as the connection line 53, which is inexpensive, resistant to bending and easy to route.

[0026] The inventor's experiments have confirmed that an extension antenna device 50 with a non-loop configuration (with the other ends 51c and 52c of the windings of each coil open) in which the first coil 51a and the second coil 52a are connected by a single connecting wire 53 functions properly. This is thought to be because, even in a non-loop configuration, an induced current generated in the first coil 51a flows through the second coil 52a for signals of a relatively high frequency (e.g., HF band: 13.56 MHz) such as those used in near-field communication (NFC). The usable frequency band is not limited to the HF band of 13.56 MHz, but can also be used within a frequency range from the LF band (up to 135 kHz) to the SHF band (2.45 GHz), which are used as RFID frequency bands.

[0027] [Usage example 1] Next, an example of a usage mode of the extension antenna device 50 of the first embodiment (hereinafter, this example will be referred to as "usage example 1") will be described. Fig. 4(a) is a plan view showing the internal structure of the extended antenna device 50 in this usage example 1. Fig. 4(b) is a side view showing the extended antenna device 50 in this usage example 1. Fig. 4(c) is a side view when the angle of the second coil portion 52 of the extended antenna device 50 in this usage example 1 is changed from the angle in Fig. 4(b). FIG. 5 is an explanatory diagram of the extended antenna device 50 in this first use example when it is attached to the smartphone 100 and used. In this usage example 1, the smartphone 100 has the functions of the reader antenna 10, the RFID reader 20, and the information processing device 30 described above.

[0028] The extended antenna device 50 of this usage example 1 has a first coil portion 51, a second coil portion 52, and a connecting wire 53 housed in a case 59 made of a magnetically permeable material. The extended antenna device 50 of this usage example 1 is attached to the smartphone 100 by an elastic attachment band 101 with the first coil portion 51 in close proximity to the upper part of the back surface of the smartphone 100 as shown in Fig. 5. Note that this usage example 1 is based on the premise that the NFC antenna coil in the smartphone 100 is arranged in the upper part of the back surface of the smartphone 100.

[0029] Typically, when reading information from an RFID tag 40 using an NFC antenna coil in a smartphone 100, the RFID tag 40 is brought close to the upper part of the back surface of the smartphone 100 to read the information. Here, in locations where RFID tags 40 are used, such as logistics centers, manufacturing plants, medical and nursing care facilities, as shown in FIGS. 6(a) to 6(c), the smartphone 100 is used to read information from the RFID tag 40. In such locations, the smartphone 100 is held by the user, for example, by attaching it to the user's body (arm) (FIGS. 6(a) and 6(b)) or hanging it from the neck (FIG. 6(c)) to prevent it from falling or being soiled, or to ensure user ease of use. In this case, the smartphone 100 is held with the front surface of the screen 100a facing outward, and the back surface of the smartphone 100, where the NFC antenna coil is located, is hidden from the user's body. While holding the smartphone, the user cannot hold the RFID tag 40 over the back surface of the smartphone 100. Therefore, the user must first remove the smartphone 100 from his or her body, and then hold the RFID tag 40 over the back of the smartphone 100, which is a cumbersome task.

[0030] Furthermore, even if the user is holding the smartphone 100, it may be possible to read information from the RFID tag 40 by holding the RFID tag 40 over the front side of the smartphone 100 in a small area close to the position of the NFC antenna coil inside the smartphone. However, because the reading range is narrow, it takes time just to align the RFID tag 40, making the reading operation complicated.

[0031] In this usage example 1, as shown in Fig. 5, the second coil portion 52 of the extension antenna device 50 attached to the smartphone 100 is arranged on the outer side (upper side) in the vertical direction of the smartphone 100. Therefore, even if the back surface of the smartphone 100 on which the NFC antenna coil is arranged is hidden by the body (arm) of the user holding the smartphone 100, as shown in Fig. 7, the second coil portion 52 of the extension antenna device 50 is not hidden by the user's body but is exposed to the outside. As a result, the user can read information from the RFID tag 40 with the smartphone 100 by simply holding the RFID tag 40 over the second coil portion 52 of the extension antenna device 50 without having to take the trouble of removing the smartphone 100 from their body.

[0032] In particular, in this use example 1, a hinge 54a is provided on the case 59 of the extension antenna device 50, and as shown in Figures 4(b) and 4(c), the angle between the first coil portion 51 and the second coil portion 52 can be changed to change the relative positional relationship between them. This allows the angle of the second coil portion 52 over which the RFID tag 40 is held to be changed, making it easier to perform the reading operation.

[0033] 8(a), when the smartphone 100 reads information from the RFID tag 40 on the name tag 205 attached to the user's breast pocket, the information displayed on the name tag 205 may be hidden by the smartphone 100, as shown in FIG. 8(b). This makes it impossible to compare the information on the RFID tag 40 displayed on the screen 100a of the smartphone 100 with the information displayed on the name tag 205, which can be inconvenient for the user.

[0034] In the extended antenna device 50 of this usage example 1, by appropriately setting the positional relationship between the first coil portion 51 and the second coil portion 52, when the second coil portion 52 is held over the RFID tag 40 on the name tag 205, it is possible to prevent the information displayed on the name tag 205 from being hidden by the smartphone 100. Therefore, in this usage example 1, it is also possible to easily compare the information on the RFID tag 40 displayed on the screen 100a of the smartphone 100 with the information displayed on the name tag 205.

[0035] [Usage example 2] Next, another example of the usage of the extension antenna device 50 of the first embodiment (hereinafter, this example will be referred to as "usage example 2") will be described. FIG. 9 is a perspective view showing an extension antenna device 50 in this second use example. In the second use example, the smartphone 100 is fixed in place and the information on the RFID tag 40 is read by the smartphone 100 at a convenient location for the user away from the smartphone 100.

[0036] In the extended antenna device 50 of this usage example 2, the first coil portion 51, the second coil portion 52, and the connecting wire 53 are housed in a mounting base 55 on which the smartphone 100 is placed. The mounting base 55 of this usage example 2 is composed of a smartphone mounting portion 55a on which the smartphone 100 is placed, a tag table portion 55b on which the user places the RFID tag 40, and a support 55c that supports the smartphone mounting portion 55a.

[0037] The first coil section 51 of the extension antenna device 50 is disposed inside the smartphone installation section 55a, and the second coil section 52 of the extension antenna device 50 is disposed inside the tag table section 55b. A single connection wire 53 that connects the first coil 51a of the first coil section 51 and the second coil 52a of the second coil section 52 is routed through the inside of the support 55c.

[0038] The extension antenna device 50 of this second use example is used, for example, by placing the mounting base 55 on a table. In this case, the tag table portion 55b, on which the user places the medicine packs (bags containing medicine) 201 and 202 equipped with the RFID tag 40, is placed near the table surface close to the user's hand. Meanwhile, the smartphone mounting portion 55a on which the smartphone 100 is placed is positioned higher than the tag table portion 55b, and the smartphone 100 placed on the smartphone mounting portion 55a is positioned close to the user's eyes. This facilitates the task of holding the RFID tag 40 over the second coil portion 52 of the tag table portion 55b, and makes the information on the RFID tag 40 displayed on the screen 100a of the smartphone 100 easy to see. As a result, user convenience is improved compared to when the information on the RFID tag 40 is directly read by the smartphone 100. In particular, this second use example significantly improves user convenience when reading information on numerous RFID tags 40 in a designated location.

[0039] 9 illustrates an example in which information from the RFID tag 40 attached to the medicine pack 201 is read, but the present invention is not limited to this. For example, the present invention may be used for a payment service that utilizes the NFC function of another smartphone or a credit card. That is, when performing a payment service using the smartphone 100 by communicating with the NFC function of another smartphone or a credit card, conventionally, it was necessary to hold the other smartphone or credit card over the smartphone 100. In contrast, according to this use example 2, the payment service using the smartphone 100 can be performed by holding the other smartphone or credit card over the smartphone 100 in a convenient location away from the smartphone 100, thereby improving convenience.

[0040] [Usage example 3] Next, still another example of the usage of the extension antenna device 50 of the first embodiment (hereinafter, this example will be referred to as "Usage Example 3") will be described. FIG. 10 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device 50 in this third use example. In this use example 3, the extension antenna device 50 is used to expand the reading area (communication area) of the reader antenna 10. Specifically, in this use example 3, the reading area for information from the RFID tag 40 is expanded to four times the area A0 of the reading area of ​​the reader antenna 10 alone.

[0041] Fig. 11(a) is an exploded view of three coil units 50A, 50B, and 50C that constitute the extended antenna device 50 of this example 3. Fig. 11(b) is an explanatory diagram showing the three coil units 50A, 50B, and 50C combined together. As shown in Figure 11(a), the extended antenna device 50 of this usage example 3 has three coil units 50A, 50B, and 50C, each including a first coil section 51 and a second coil section 52 connected to each other by a single connecting wire 53.

[0042] In this example of use 3, the first coil portions 51A, 51B, and 51C of the three coil units 50A, 50B, and 50C are arranged in locations where they are connected to each other by electromagnetic induction. More specifically, as shown in Fig. 11(b), in the three coil units 50A, 50B, and 50C in this example of use 3, the first coil portions 51A, 51B, and 51C are arranged so that they overlap each other with their axes approximately parallel to each other. The second coil portions 52A, 52B, and 52C are arranged in locations where they are not connected to each other by electromagnetic induction.

[0043] 10, the first coil portions 51A, 51B, and 51C of the three coil units 50A, 50B, and 50C, which are arranged so as to overlap each other, are arranged in locations connected to the reader antenna 10 by electromagnetic induction, specifically in the reading area A0 (communication area) of the reader antenna 10. As a result, a magnetic field generated in the coil 11 of the reader antenna 10 by a signal from the RFID reader 20 generates an induced current signal by electromagnetic induction in the coil 51a of each of the first coil portions 51A, 51B, and 51C of the three coil units 50A, 50B, and 50C.

[0044] These induced current signals flow into the second coils 52a of the second coil sections 52A, 52B, and 52C via the respective connection lines 53A, 53B, and 53C. Therefore, in the second coil sections 52A, 52B, and 52C of the three coil units 50A, 50B, and 50C, magnetic fields are generated in accordance with the induced current signals corresponding to the signals from the RFID reader 20. The magnetic field generation areas of the second coil sections 52A, 52B, and 52C become the respective reading areas A1 to A3 (communication areas).

[0045] When the RFID tag 40 approaches each of the second coil portions 52A, 52B, and 52C of the three coil units 50A, 50B, and 50C, a magnetic field generated by the second coil 52a of the corresponding second coil portion 52A, 52B, and 52C passes through the coil 41 of the RFID tag 40, causing an induced current to flow in the coil 41 of the RFID tag 40. As a result, a signal of the induced current is input to the transmitting / receiving terminal of the NFC chip 42, and a signal from the RFID reader 20 is transmitted.

[0046] A signal output from the NFC chip 42 is transmitted by electromagnetic induction from the coil 41 of the RFID tag 40 to the second coil 52a of the second coil section 52A, 52B, 52C of the corresponding coil unit among the three coil units 50A, 50B, 50C. As a result, an induced current signal generated in the second coil 52a flows into the first coil 51a of the first coil section 51 via the connection line 53, and a magnetic field corresponding to the induced current signal corresponding to the signal from the NFC chip 42 is generated in the first coil 51a. As a result, the magnetic field generated in the first coil 51a passes through the coil 11 of the reader antenna 10, and an induced current flows in the coil 11 of the reader antenna 10, and a signal of the induced current is transmitted to the RFID reader 20.

[0047] Furthermore, in the extension antenna device 50 of this use example 3, information from the RFID tag 40 can be read even in the reading area A0 (communication area) of the reader antenna 10, in which all of the first coil portions 51A, 51B, and 51C of the three coil units 50A, 50B, and 50C are arranged in an overlapping state. Therefore, in this use example 3, information from the RFID tag 40 can be read using the reading area A0 of the reader antenna 10 and the reading areas A1 to A3 of the second coil portions 52A, 52B, and 52C of the three coil units 50A, 50B, and 50C. Because the reading areas A0 to A3 are approximately the same size, the extension antenna device 50 of this use example 3 can expand the reading area for information from the RFID tag 40 to four times the size of the reading area A0 of the reader antenna 10 alone.

[0048] According to Use Example 3, as shown in Fig. 10, it is possible to quickly read information from each RFID tag 40 of 24 medicine packs 201 that are held on a sheet 202 in an array of six horizontally and four vertically. Specifically, the RFID tags 40 on the sheet 202 are distributed over an area approximately four times the size of the reading area A0 of the reader antenna 10. Therefore, if the information on these RFID tags 40 is to be read using only the reader antenna 10, the reading operation must be performed at least four times. In contrast, by using the extension antenna device 50 of Use Example 3, it is possible to complete the reading of information on each RFID tag 40 on the sheet 202 in a single operation.

[0049] [Usage example 4] Next, still another example of the usage of the extension antenna device 50 of the first embodiment (hereinafter, this example will be referred to as "Usage Example 4") will be described. FIG. 12 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device 50 in this fourth use example. In this use example 4, the information reading area (communicable area) of the RFID reader 20 is expanded to a place far away from the reader antenna 10.

[0050] Similar to the above-described Usage Example 3, the extended antenna device 50 of Usage Example 4 also includes three coil units 50A, 50B, and 50C, each including a first coil portion 51 and a second coil portion 52 interconnected by a single connecting wire 53. However, in Usage Example 4, the three coil units 50A, 50B, and 50C are magnetically coupled in series to expand the information reading area (communication area).

[0051] 12, the first coil portion 51A of the first coil unit 50A is disposed in a location connected to the reader antenna 10 by electromagnetic induction, specifically in a reading area A0 (communication area) of the reader antenna 10. Also, as shown in FIG. 12, the first coil portion 51B of the second coil unit 50B is disposed in a location connected to the second coil portion 52A of the first coil unit 50A by electromagnetic induction, i.e., in a reading area A1 (communication area) of the second coil portion 52A of the first coil unit 50A. Also, as shown in FIG. 12, the first coil portion 51C of the third coil unit 50C is disposed in a location connected to the second coil portion 52B of the second coil unit 50B by electromagnetic induction, i.e., in a reading area A2 (communication area) of the second coil portion 52B of the second coil unit 50B.

[0052] In this usage example 4, a magnetic field generated in the coil 11 of the reader antenna 10 by a signal from the RFID reader 20 generates an induced current signal by electromagnetic induction in the coil 51a of the first coil section 51A of the first coil unit 50A. This induced current signal flows into the second coil 52a of the second coil section 52A via the connection line 53A. Therefore, a magnetic field corresponding to the induced current signal corresponding to the signal from the RFID reader 20 is generated in the second coil section 52A of the first coil unit 50A, forming a reading area A1 (a communication area).

[0053] Furthermore, the magnetic field generated by the second coil portion 52A of the first coil unit 50A generates an induced current signal by electromagnetic induction in the coil 51a of the first coil portion 51B of the second coil unit 50B. This induced current signal flows into the second coil 52a of the second coil portion 52B via the connection line 53B. Therefore, a magnetic field corresponding to the induced current signal corresponding to the signal from the RFID reader 20 is also generated in the second coil portion 52B of the second coil unit 50B, forming a reading area A2 (communication area).

[0054] Similarly, the magnetic field generated by the second coil portion 52B of the second coil unit 50B generates an induced current signal by electromagnetic induction in the coil 51a of the first coil portion 51C of the third coil unit 50C. This induced current signal flows into the second coil 52a of the second coil portion 52C via the connection line 53C. Therefore, a magnetic field corresponding to the induced current signal corresponding to the signal from the RFID reader 20 is also generated in the second coil portion 52C of the third coil unit 50C, forming a reading area A3 (communication area).

[0055] According to the extension antenna device 50 of this Usage Example 4, the information reading area can be extended up to a distance equivalent to three coil units arranged in series from the reader antenna 10. Note that if four or more coil units are arranged in series, the information reading area can be extended even farther.

[0056] In this use example 4 as well, the information of the RFID tag 40 can be read by the reading area A0 (communication area) of the reader antenna 10 and the reading areas A1 to A3 of the second coil portions 52A, 52B, and 52C of the three coil units 50A, 50B, and 50C. Therefore, in this use example 4 as well, the reading area for the information of the RFID tag 40 can be expanded to four times the size of the reading area A0 of the reader antenna 10 alone, as in the above-mentioned use example 3.

[0057] 13, one possible method for extending the information reading area to a location farther away from the reader antenna 10 is to create four coils 61 to 64 using a single conductor wire and connect the four coils 61 to 64 in series with a single connecting wire 65. However, in this configuration, the reactance 2πfL of each coil is added to the induced current flowing through the coil 61 due to electromagnetic induction caused by the magnetic field of the reader antenna 10, and the farther the coil is from the reader antenna 10, the greater the attenuation of the induced current signal, resulting in a narrower communication range (communication distance).

[0058] In contrast, in the extension antenna device 50 of this usage example 4, coil units 50A to 50C, each consisting of two coils 51 and 52, are connected to each other by electromagnetic induction to propagate an induced current signal. Therefore, even in a coil unit far from the reader antenna 10, attenuation of the induced current signal is small, and the communication range (communication distance) can be maintained.

[0059] [Usage example 5] Next, still another example of the usage of the extension antenna device 50 of the first embodiment (hereinafter, this example will be referred to as "usage example 5") will be described. FIG. 14 is an explanatory diagram showing an example in which the extension antenna device 50 in this use example 5 is mounted on a robot arm 120. In this usage example 5, six coil units 50A to 50F, each including a first coil section 51 and a second coil section 52 interconnected by a single connecting wire 53, are magnetically coupled in series, similar to the above-described usage example 4.

[0060] 14, robot arm 120 on which extension antenna device 50 is mounted is made up of base 121, joint mechanisms 122A-122E, arm sections 123A-123C, and end effector 124. Each of joint mechanisms 122A-122E of robot arm 200 is a rotation mechanism with one degree of freedom, and robot arm 120 as a whole achieves six degrees of freedom.

[0061] The base end of a first arm unit 123A is attached to a first joint mechanism 122A fixed on a base 121, and a second joint mechanism 122B is attached to a tip end of the first arm unit 123A. The base end of the second arm unit 123B is attached to the second joint mechanism 122B, and a third joint mechanism 122C is attached to a tip end of the second arm unit 123B. The base end of the third arm unit 123C is attached to the third joint mechanism 122C, and a fourth joint mechanism 122D is attached to a tip end of the third arm unit 123C. The fourth joint mechanism 122D is attached to a fifth joint mechanism 122E having a rotation axis perpendicular to the rotation axis of the fourth joint mechanism 122D, and the base end of the fourth arm unit 123D is attached to the fifth joint mechanism 122E. An end effector 124 is attached to the tip of the fourth arm portion 123D.

[0062] In the robot arm 200, the magnetic engagement points between the coil units 50A to 50F of the extension antenna device 50 are arranged in the respective joint mechanisms 122A to 122E, as shown in Fig. 14. Specifically, the first coil portion 51A of the first coil unit 50A is arranged in the reading area (communication area) of the reader antenna 10, and the second coil portion 52A of the first coil unit 50A is arranged on the pedestal 121. The first coil portion 51B of the second coil unit 50B is arranged in the reading area of ​​the second coil portion 52A of the first coil unit 50A on the pedestal 121, and the second coil portion 52B of the second coil unit 50B is arranged in the first joint mechanism 122A.

[0063] Similarly, the first coil portion and the second coil portion of the other coil units 50C to 50F are arranged in the corresponding joint mechanisms 122B to 122E. The first coil portion 51B of the last sixth coil unit 50F is arranged in the reading area of ​​the second coil portion 52E of the fifth coil unit 50E in the fifth joint mechanism 122E, and the second coil portion 52F of the sixth coil unit 50F is arranged in the end effector 124.

[0064] According to this Usage Example 5, by controlling the robot arm 120, the second coil portion 52F of the sixth coil unit 50F attached to the end effector 124 can be moved to any location to which the end effector 124 of the robot arm 120 can be moved. Therefore, by controlling the robot arm 120, the end effector 124 can be brought closer to the RFID tag 40 placed at any location. As a result, the information signal of the RFID tag 40 can be received by electromagnetic induction via the second coil portion 52F of the end effector 124, and the information of the RFID tag 40 can be read by the RFID reader 20 via each of the coil units 50A to 50F of the extension antenna device 50.

[0065] In a configuration like the conventional extension antenna device in which the coil on the end effector and the coil located on the reader antenna 10 installed outside the robot arm are connected by a shielded wire such as a coaxial cable, the shielded wire is subjected to mechanical loads such as bending and twisting when the joint mechanism of the robot arm is driven, and there is a risk that it may break due to mechanical fatigue.

[0066] In contrast, according to Use Example 5, at the magnetic engagement points between the coil units 50A-50F, the first coil portion of one coil unit and the second coil portion of the other coil unit are arranged in a non-contact manner so that they overlap closely and their coil axes are parallel to the rotation axes of the corresponding joint mechanisms 122A-122E. Therefore, in Use Example 5, even when the joint mechanisms 122A-122E are driven, mechanical contact such as rubbing does not occur at the magnetic engagement points between the coil units 50A-50F, and the connecting wires are not subjected to mechanical loads such as twisting. Therefore, when the joint mechanisms of the robot arm 120 are driven, the connecting wires are not subjected to mechanical loads such as bending or twisting, and are not broken due to mechanical fatigue.

[0067] Furthermore, according to this use example 5, the first coil portion and the second coil portion in each of the coil units 50A to 50F are connected by a single connecting wire, so that the routing of the connecting wire within the robot arm 120 is also easy.

[0068] [Usage example 6] Next, still another example of the usage of the extension antenna device 50 of the first embodiment (hereinafter, this example will be referred to as "Usage Example 6") will be described. FIG. 15 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device 50 in this sixth example of use. FIG. 16 is an explanatory diagram showing the configuration of an extension antenna device 50 in this sixth example of use. In this use example 6, antennas attached to the XY tables 206 and 207 are used to read information from an RFID tag 40 located at any point on the XY plane.

[0069] This use example 6 is an example of use in a medication support system used for medication preparation by medication assistants such as nurses and caregivers in hospitals, nursing homes, etc. In more detail, in order to reduce the working time of medication assistants working in nursing homes, etc. and to prevent medication errors, it is confirmed whether the medication for each resident (medication recipient) placed in each medication pack 201 has been correctly placed in the corresponding resident's small box (medication container) 204.

[0070] As shown in Figure 15, medication tray 203 is provided with partition walls that separate the compartments into which each dispensing box 204 is set. Medication tray 203 has 35 compartments, each of which can be expressed as an element of a matrix consisting of 7 columns and 5 rows. As a result, each of the 35 compartments on medication tray 203 can be uniquely identified by the element and address of the 7-column, 5-row matrix.

[0071] Medicine packs 201 equipped with RFID tags 40 are stored in the subdivision boxes 204 set in each compartment of the medicine distribution tray 203. The RFID tag 40 equipped on each medicine pack 201 stores medication-related information such as the name of the person taking the medicine in that medicine pack 201 and the timing of taking the medicine.

[0072] An extension antenna device 50 is incorporated into the XY tables 206, 207 of this usage example 6. Specifically, as shown in Fig. 16, a first coil section 51 of the extension antenna device 50 is disposed in the reading area (communication area) of the reader antenna 10, and a second coil section 52 of the extension antenna device 50 is disposed at the antenna position of the XY tables 206, 207. A single connection line 53 connecting the first coil section 51 and the second coil section 52 is wired on the XY tables 206, 207 so that excessive tension is not generated in the connection line 53 even when the XY tables 206, 207 are driven, as shown in Fig. 16.

[0073] In a configuration like the conventional extended antenna device in which a coil placed at the antenna position of the XY tables 206, 207 and a coil placed on the reader antenna 10 installed outside the XY table are connected by a shielded wire such as a coaxial cable, the shielded wire is subjected to mechanical loads such as bending and twisting when the XY table is driven, and is prone to breaking due to mechanical fatigue.

[0074] In contrast, the single connecting wire 53 of Example 6 can be easily routed and is resistant to bending, so that the connecting wire 53 is less likely to break due to mechanical fatigue even if it is subjected to mechanical loads such as bending and twisting when the XY tables 206 and 207 are driven. Moreover, the connecting wire 53 of Example 6 can be easily routed on the XY tables 206 and 207.

[0075] In this usage example 6, by placing the medication tray 203 on the XY tables 206, 207 and driving the XY tables 206, 207, medication-related information corresponding to the medication in the medication pack 201 can be read from the RFID tag 40 attached to the medication pack 201 in the dispensing box 204 set in each compartment of the medication tray 203, and displayed and confirmed on the screen of the information processing device 30. At this time, according to this usage example 6, by using the position information of the XY tables 206, 207 at the time the information is read from the RFID tag 40, it is possible to distinguish and read the information of the RFID tag 40 for each compartment of the medication tray 203 or for each dispensing box 204. Therefore, it is possible to display on the screen of the information processing device 30 which information (medication-related information) of the displayed RFID tag 40 belongs to which dispensing box 204 set in which compartment of the medication tray 203.

[0076] This allows the medication assistant to perform confirmation work by comparing the medication-related information displayed on the screen of the information processing device 30 with the medication-related information displayed in the corresponding subdivision box 204 on the medication tray 203 or the medication-related information displayed on the medicine pack 201 contained in the subdivision box 204.

[0077] [Variation 1] Next, a modified example of the extension antenna device of the first embodiment (hereinafter, this modified example will be referred to as "Modified Example 1") will be described. FIG. 17 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device 70 in the first modification. The extension antenna device 70 of this modified example 1, like the extension antenna device 50 of the above-described embodiment 1, includes a first coil portion 71, a second coil portion 72, and a single connecting wire 73 connecting these coils 71 and 72. However, the extension antenna device 70 of this modified example 1 also includes a third coil portion 74 in which part of the single connecting wire 73 is wound.

[0078] In other words, in the extended antenna device 70 of the present modified example 1, one end of the winding of the third coil of the third coil portion 74 is connected to one end of the first coil of the first coil portion 71, and the other end of the winding of the third coil of the third coil portion 74 is connected to one end of the second coil of the second coil portion 72. The other end 71c of the winding of the first coil and the other end 72c of the winding of the second coil are both open.

[0079] 17 , the third coil unit 74 is disposed in a location where it is connected to the reader antenna 10 by electromagnetic induction, specifically in the reading area A0 (communication area) of the reader antenna 10. As a result, a magnetic field generated in the coil 11 of the reader antenna 10 by a signal from the RFID reader 20 generates an induced current signal in the third coil of the third coil unit 74 by electromagnetic induction.

[0080] This induced current signal flows from both ends of the winding of the third coil of the third coil portion 74 to each of the coils of the first coil portion 71 and the second coil portion 72 via the connecting wires 73. Therefore, in the first coil portion 71 and the second coil portion 72, a magnetic field is generated in accordance with the induced current signal corresponding to the signal from the RFID reader 20. Therefore, the magnetic field generation areas of the first coil portion 71 and the second coil portion 72 become the respective reading areas A1 and A2 (communication areas).

[0081] When the RFID tag 40 approaches the first coil unit 71 and the second coil unit 72, the magnetic field generated by the corresponding coil of the coil unit 71, 72 passes through the coil 41 of the RFID tag 40, causing an induced current to flow in the coil 41 of the RFID tag 40. As a result, a signal of the induced current is input to the transmitting / receiving terminal of the NFC chip 42, and a signal from the RFID reader 20 is transmitted.

[0082] A signal output from the NFC chip 42 is transmitted by electromagnetic induction from the coil 41 of the RFID tag 40 to the coils of the corresponding coil units 71 and 72. As a result, an induced current signal generated in the coil flows into the coil of the third coil unit 74 via the connection line 73, and a magnetic field corresponding to the induced current signal corresponding to the signal from the NFC chip 42 is generated in the third coil of the third coil unit 74. As a result, the magnetic field generated in the third coil passes through the coil 11 of the reader antenna 10, and an induced current flows in the coil 11 of the reader antenna 10, and a signal of the induced current is transmitted to the RFID reader 20.

[0083] When the RFID tag 40 is brought close to the third coil portion 74, the information is directly read by the reader antenna 10.

[0084] According to this first modification, information on the RFID tag 40 can be read using the reading area A0 of the reader antenna 10 and the reading areas A1 and A2 of the first coil portion 71 and the second coil portion 72. Since the size of each of the reading areas A0 to A2 is approximately the same, the extension antenna device 70 of this first modification can expand the reading area for information on the RFID tag 40 to three times the size of the reading area A0 of the reader antenna 10 alone, using only a single coil unit (extension antenna device 70) made up of a single conductor wire.

[0085] [Usage example 7] Next, an example of a usage mode of the extension antenna device 70 of the first modification (hereinafter, this example will be referred to as "Usage Example 7") will be described. FIG. 18 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device 70 in this seventh use example. This use example 7 is an example of extending the communication distance of the reading area (communication area). Specifically, in the extended antenna device 70 of this use example 7, as shown in FIG. 18, the coils of the first coil section 71 and the second coil section 72 are arranged so that their axes are approximately parallel and overlap each other. In particular, if their axes completely overlap, the interaction between the two coils may affect the frequency tuning of the coils, so it is preferable to separate the two coils by a distance of several millimeters. Furthermore, the centers of the coil cores may be shifted to create a portion with a strong magnetic field.

[0086] In this usage example 7, the third coil section 74 is disposed in a location where it is connected to the reader antenna 10 by electromagnetic induction, specifically in the reading area A0 (communication area) of the reader antenna 10. As a result, a magnetic field generated in the coil 11 of the reader antenna 10 by a signal from the RFID reader 20 generates an induced current signal by electromagnetic induction in the third coil of the third coil section 74. Then, this induced current signal flows into each of the first coil section 71 and the second coil section 72 via the connecting wire 73, and a magnetic field corresponding to the induced current signal is generated in each of the first coil section 71 and the second coil section 72.

[0087] In this case, in this use example 7, the coils of the first coil section 71 and the second coil section 72 are arranged so that their axes are approximately parallel and overlap each other. Therefore, the magnetic fields generated by these coils reinforce each other. As a result, the communication distance of the reading area (communication area) of the first coil section 71 and the second coil section 72 is expanded in the axial direction of each coil. It is also expanded slightly in the radial direction relative to the axial direction of each coil. As a result, this use example 7 makes it possible to communicate with RFID tags 40 located far from the first coil section 71 and the second coil section 72.

[0088] [Usage example 8] Next, another example of the usage of the extension antenna device 70 of the first modification (hereinafter, this example will be referred to as "Usage Example 8") will be described. FIG. 19 is an explanatory diagram of an example in which the extension antenna device 70 in this use example 8 is applied to a storage box 130 equipped with an RFID tag 40. As shown in FIG. 19, the extension antenna device 70 of this use example 8 is arranged so that the coil axes of the first coil portion 71, the second coil portion 72, and the third coil portion 74 are perpendicular to each other.

[0089] In this usage example 8, the third coil portion 74 is arranged so as to face the coil of the RFID tag 40 provided in the storage box 130. The first coil portion 71 and the second coil portion 72 connected to each end of the winding of the third coil portion 74 are arranged in the storage box 130 so that their coil axes are perpendicular to each other. For example, as shown in FIG. 19 , when the RFID tag 40 is provided on the bottom surface of the cubic storage box 130, the third coil portion 74 of the extension antenna device 70 is arranged on the bottom surface of the storage box 130 so as to overlap the RFID tag 40. Meanwhile, the first coil portion 71 and the second coil portion 72 of the extension antenna device 70 are arranged on the side surfaces of the storage box 130 that do not face each other.

[0090] In this manner, if the storage box 130 has the extension antenna device 70 installed, the information of the RFID tag 40 in the storage box 130 can be read not only by the reader antenna 10 placed at position A shown in Figure 20, but also by the reader antenna 10 placed at position B or position C.

[0091] More specifically, the reader antenna 10 placed at position A shown in Fig. 20 faces the bottom surface of the storage box 130, and therefore most of the magnetic flux generated in the coil 11 of the reader antenna 10 penetrates the coil 41 of the RFID tag 40 on the bottom surface of the storage box 130, enabling signal transmission by electromagnetic induction. In contrast, the reader antennas 10 placed at positions B and C shown in Fig. 20 face the side surface of the storage box 130, and most of the magnetic flux generated in the coil 11 of these reader antennas 10 cannot penetrate the coil 41 of the RFID tag 40 on the bottom surface of the storage box 130, and therefore cannot transmit signals by electromagnetic induction.

[0092] However, according to this Usage Example 8, the first coil portion 71 and the second coil portion 72 of the extension antenna device 70 are arranged on the side surface of the storage box 130. As a result, most of the magnetic flux generated by the coil 11 of the reader antenna 10 arranged at position B or position C shown in Fig. 20 can penetrate the coils of the first coil portion 71 and the second coil portion 72 on the side surface of the storage box 130. As a result, even with the coil 11 of the reader antenna 10 arranged at position B or position C shown in Fig. 20, it is possible to read information from the RFID tag 40 on the bottom surface of the storage box 130 via the first coil portion 71 and the second coil portion 72.

[0093] In other words, for example, when any side of the storage box 130 is faced to the reader antenna 10 placed at position A shown in Figure 20 (even when the side on which the RFID tag 40 is not placed is faced), information can be read from the RFID tag 40 of the storage box 130.

[0094] 19 and 20, the extension antenna device 70 of Usage Example 8 is applied to extend the coil antenna of the RFID tag 40, but the extension antenna device 70 of Usage Example 8 may also be applied to extend the reader antenna 10. For example, as shown in Fig. 21, a third coil section 74 is placed in the reading area of ​​the reader antenna 10, and a first coil section 71 and a second coil section 72 are placed in the reading area so as to face each other in the X direction and the Y direction.

[0095] This makes it possible to read information from the RFID tag 40 via any of the coil sections 71, 72, and 74, regardless of the posture of the RFID tag 40 within the reading area surrounded by the three coil sections 71, 72, and 74.

[0096] [Variation 2] Next, another modification of the extension antenna device of the first embodiment (hereinafter, this modification will be referred to as "Modification 2") will be described. FIG. 22 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device 80 in the second modification. The extension antenna device 80 of the present modified example 2 includes one first coil portion 81 and multiple (here, six) second coil portions 82A to 82F. In the extension antenna device 80, a coil switcher 85 is disposed on a single connection line 83 connected to one end of the winding of the first coil portion 81.

[0097] FIG. 23 is an explanatory diagram showing the configuration of the coil switch 85 provided in the extension antenna device 80 of the second modification. The coil switch 85 has a first terminal 85a, which is a connection terminal to which the connection wire 83 from the first coil portion 81 is connected, and is a connection switch that switches the connection destination of this first terminal 85a to one of six second terminals 85b1 to 85b6, which are connection receiving terminals. The second coil portions 82A to 82F are connected to the second terminals 85b1 to 85b6 via the connection wires 83A to 83F, respectively.

[0098] The coil switch 85 is connected to the information processing device 30 by a cable 86. The switching operation of the second terminals 85b1-85b6 in the coil switch 85 is controlled by the information processing device 30. Therefore, the information processing device 30 recognizes which of the second terminals 85b1-85b6 is connected to it. Therefore, the information processing device 30 can receive information of the RFID tag 40 read by each of the second coil sections 82A-82F when each of the second terminals 85b1-85b6 is connected, via the first coil section 81, the reader antenna 10, and the RFID reader 20, and store the information separately for each of the second coil sections 82A-82F.

[0099] FIG. 24 is a flowchart showing the flow of reading information from the RFID tag 40 using the extension antenna device 80 of the second modification. When the RFID reader 20 is started (S1), the information processing device 30 controls the coil switch 85 to switch the connections of the six second terminals 85b1 to 85b6 (second coil portions 82A to 82F) in a predetermined order. Specifically, the information processing device 30 first controls the coil switch 85 to connect to the first second terminal 85b1 (second coil portion 82A) (S2). Thereafter, the information processing device 30 causes the RFID reader 20 to read information from the RFID tag 40 via the first second coil portion 82A connected to the second terminal 85b1.

[0100] At this time, when the RFID reader 20 has completed reading the information (Yes in S3), the information processing device 30 receives the information of the RFID tag 40 read via the first second coil portion 82A from the RFID reader 20 and stores it in a predetermined storage area (S4). Then, the information processing device 30 switches the connection to the next (second) second terminal 85b2 (second coil portion 82B) (Yes in S5, S6). On the other hand, if, for example, there is no RFID tag 40 in the reading area (communication area) of the first second coil portion 82A and the RFID reader 20 has not completed reading the information (No in S3), the information processing device 30 simply switches the connection to the next (second) second terminal 85b2 (second coil portion 82B) (Yes in S5, S6).

[0101] Thereafter, the information processing device 30 sequentially reads information from the RFID tag 40 for all remaining second coil portions 82B-82F (S3-S6). Then, when the information processing device 30 has completed the information reading operation for the last second coil portion 82F (No in S5), it performs predetermined information processing on the information from the RFID tag 40 that has been read and stored via each of the second coil portions 82B-82F (S7).

[0102] By using the extension antenna device 80 of the present modified example 2, it is possible to store information of the read RFID tag 40 by distinguishing which of the second coil units 82A to 82F the information was read through. By using such an extension antenna device 80, it is possible to store information of the RFID tag 40 for each location in association with each location by arranging each of the second coil units 82A to 82F in a predetermined location.

[0103] In particular, the extension antenna device 80 of the present modified example 2 makes it possible to read information from RFID tags 40 located at multiple locations by distinguishing between the locations using a single reader antenna 10. Therefore, compared to a configuration in which an individual reader antenna is installed for each location to read information from the RFID tags 40 at each location, an RFID tag reading system 1 with a simpler configuration and lower cost can be realized.

[0104] Moreover, in the extension antenna device 80 of the present modification 2, there is no need to suppress interference between the connection wires 83, 83A to 83F that connect the first coil portion 81 and each of the second coil portions 82A to 82F. Therefore, there is no need to use a shielded wire such as a coaxial cable as in the conventional extension antenna device, and it is possible to use inexpensive connection wires 83, 83A to 83F.

[0105] Furthermore, in the extension antenna device 80 of the present modified example 2, it is not necessary to use a shielded wire such as a coaxial cable as in the conventional extension antenna device, so it is possible to use the connection lines 83, 83A to 83F, which are strong against bending and easy to pull around. Therefore, there is a high degree of freedom in the wiring layout of the connection lines 83, 83A to 83F.

[0106] [Usage example 9] Next, an example of a usage mode of the extension antenna device 80 of the second modification (hereinafter, this example will be referred to as "Usage Example 9") will be described. FIG. 25 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device 80 in this ninth example of use.

[0107] This use example 9 is an example of use in a medication support system used for medication preparation by medication assistants such as nurses and caregivers in hospitals, nursing homes, etc. In more detail, in order to reduce the working time of medication assistants working in nursing homes, etc. and to prevent medication errors, it is confirmed whether the medication for each resident (medication recipient) placed in each medication pack 201 has been correctly placed in the corresponding resident's small box (medication container) 204.

[0108] As shown in Figure 25, medication tray 203 is provided with partition walls that separate the compartments into which each dispensing box 204 is set. Medication tray 203 has 35 compartments, each of which can be expressed as an element of a matrix consisting of 7 columns and 5 rows. As a result, each of the 35 compartments on medication tray 203 can be uniquely identified by the element and address of the 7-column, 5-row matrix.

[0109] The medication tray 203 has second coil sections 82A, 82B, 82C, etc. of the extension antenna device 80 installed on the bottom wall of each compartment. The second coil sections 82A, 82B, 82C, etc. are connected to second terminals 85b1, 85b2, 85b3, etc. of the coil switcher 85 of the extension antenna device 80 via respective connection lines.

[0110] As shown in Fig. 26, medicine packs 201 equipped with RFID tags 40 are housed in the dispensing boxes 204 set in each compartment of the medicine dispensing tray 203. The RFID tag 40 attached to each medicine pack 201 stores medication-related information regarding medication, such as the name of the person taking the medicine in that medicine pack 201 and the timing of taking the medicine. By setting the dispensing boxes 204 containing the medicine packs 201 in each compartment of the medicine dispensing tray 203, information can be read from the RFID tags 40 of the medicine packs 201 in each dispensing box 204 via the second coils 82A, 82B, 82C, ... provided on the bottom wall of each compartment.

[0111] According to this Usage Example 9, medication-related information corresponding to the medicine in the medicine pack 201 can be read from the RFID tag 40 provided on the medicine pack 201 in the dispensing box 204 set in each compartment of the medication tray 203, and can be displayed and confirmed on the screen of the information processing device 30. At this time, according to this Usage Example 9, the information on the RFID tag 40 can be read separately for each compartment of the medication tray 203 or for each dispensing box 204. Therefore, it is possible to display on the screen of the information processing device 30 which information (medication-related information) of the displayed RFID tag 40 belongs to which dispensing box 204 set in which compartment of the medication tray 203.

[0112] This allows the medication assistant to perform confirmation work by comparing the medication-related information displayed on the screen of the information processing device 30 with the medication-related information displayed in the corresponding subdivision box 204 on the medication tray 203 or the medication-related information displayed on the medicine pack 201 contained in the subdivision box 204.

[0113] Furthermore, information read from the RFID tag 40 attached to the medicine pack 201 in the subdivision box 204 set in each compartment of the medicine distribution tray 203 may be used to control a robot arm (picking robot) 205, as shown in FIG.

[0114] [Usage example 10] Next, another example of the usage of the extension antenna device 80 of the second modification (hereinafter, this example will be referred to as "usage example 10") will be described. FIG. 28 is an explanatory diagram showing a storage system 300 for storing medicines and the like that are subject to management obligations. FIG. 29 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device 80 used in a storage system 300. The present use example 10 is an example in which the extension antenna device 80 of the second modification is used in a storage system 300 that stores medicines and the like that are subject to management obligations.

[0115] 28, the storage system 300 of this usage example 10 includes a storage case 301 that stores chemicals 310 and 311, an opening / closing door 302 that opens and closes the storage case 301, and an automatic locking mechanism 303 that locks the opening / closing door 302. The automatic locking mechanism 303 is communicably connected to an information processing device 30 such as a tablet terminal, and the locking and unlocking of the opening / closing door 302 by the automatic locking mechanism 303 is controlled by the information processing device 30.

[0116] Medicine placement locations are provided in the storage case 301, where specific medicines 310, 311 are placed. In this usage example 10, as shown in Fig. 29, second coil portions 82A to 82F of the extension antenna device 80 are respectively installed in the medicine placement locations. The second coil portions 82A to 82F are respectively connected to second terminals 85b1 to 85b6 of the coil switcher 85 of the extension antenna device 80 via respective connection lines.

[0117] In this usage example 10, the medicines 310, 311 stored in the storage case 301 are provided with RFID tags 40 on their bottoms. The RFID tags 40 of each of the medicines 310, 311 store medicine-related information about that medicine. When each of the medicines 310, 311 is placed in a medicine placement location within the storage case 301, information can be read from the RFID tags 40 of each of the medicines 310, 311 via the second coils 82A to 82F provided in each medicine placement location.

[0118] According to this use example 10, it is possible to read the medicine-related information corresponding to each medicine 310, 311 from the RFID tag 40 attached to the medicine 310, 311 placed in the medicine placement location of the storage case 301, and display and confirm it on the screen of the information processing device 30. At this time, according to this use example 10, it is possible to distinguish and read the information of the RFID tag 40 for each medicine placement location of the storage case 301. Therefore, it is possible to display on the screen of the information processing device 30 which medicine placement location in the storage case 301 the information (medicine-related information) of the displayed RFID tag 40 belongs to the medicine 310, 311.

[0119] This allows drug users and drug managers to perform confirmation work by comparing the drug-related information displayed on the screen of the information processing device 30 with the drug-related information displayed on the labels of the drugs 310, 311 placed in the corresponding drug storage locations.

[0120] Furthermore, in this usage example 10, the coil switch 85 of the extension antenna device 80 is provided with another second terminal in addition to the second terminals 85b1 to 85b6 connected to the second coil portions 82A to 82F. Another second coil portion 82Z disposed outside the storage case 301 is connected to this other second terminal. This other second coil portion 82Z is ​​used to read information from the ID card 208 equipped with the RFID tag 40.

[0121] Therefore, according to this usage example 10, it is possible to read drug-related information from the RFID tags 40 of the drugs 310, 311 in the storage case 301 and ID information from the ID cards 208 of the drug users and drug managers with one extension antenna device 80 and one reader antenna 10. Therefore, compared to when these readings are performed using separate configurations, it is possible to realize an RFID tag reading system with a simpler configuration and lower cost.

[0122] In this use example 10, the information processing device 30 reads ID information from the ID card 208 of the medicine user or medicine manager, for example, and performs a process of unlocking the openable door 302 locked by the automatic locking mechanism 303 on the condition that the authentication process is completed. This authentication process may be combined with, for example, face authentication process using a camera 304, which is an imaging device communicably connected to the information processing device 30, as shown in Fig. 29 .

[0123] Furthermore, it is difficult to manage the remaining amounts (or used amounts) of the medicines 310, 311 simply by reading information from the RFID tags 40 of the medicines 310, 311 via the second coil portions 82A-82F. In order to manage the remaining amounts (or used amounts) of the medicines 310, 311, weight sensors 305A-305F communicably connected to the information processing device 30 may be installed in each medicine placement location of the storage case 301, as shown in Fig. 30 .

[0124] [Usage example 11] Next, still another example of the usage of the extension antenna device 80 of the second modification (hereinafter, this example will be referred to as "Usage Example 11") will be described. FIG. 31 is an explanatory diagram showing an RFID tag reading system 1 using an extension antenna device 80 in this eleventh example of use. This use example 11 is an example in which the extension antenna device 80 of the second modification is used in a tool management system 400 that stores and manages tools.

[0125] As shown in Fig. 31, the tool management system 400 of this usage example 11 includes a tool storage area 401 in which various tools 410-414 are stored. The tool storage area 401 is provided with tool storage locations in which specific tools 410-414 are placed. In this usage example 11, as shown in Fig. 31, second coil sections 82A-82E of the extension antenna device 80 are installed in each tool storage location. The second coil sections 82A-82E are connected to second terminals 85b1-85b5 of the coil switcher 85 of the extension antenna device 80 via respective connection lines.

[0126] In this usage example 11, each of the tools 410-414 stored in the tool storage area 401 is equipped with an RFID tag 40. The RFID tag 40 of each of the tools 410-414 stores tool-related information about that tool. By placing each of the tools 410-414 in a tool storage location within the tool storage area 401, information can be read from the RFID tag 40 of each of the tools 410-414 via the second coil units 82A-82E provided in each tool storage location.

[0127] According to this use example 11, tool-related information corresponding to each of the tools 410-414 can be read from the RFID tag 40 attached to each of the tools 410-414 placed in a tool storage location in the tool storage area 401, and can be displayed and confirmed on the screen of the information processing device 30. At this time, according to this use example 11, the information on the RFID tag 40 can be read separately for each tool storage location in the tool storage area 401. Therefore, the screen of the information processing device 30 can display which tool storage location in the tool storage area 401 the information on the displayed RFID tag 40 (tool-related information) belongs to.

[0128] This allows tool users and tool managers to perform confirmation work by comparing the tool-related information displayed on the screen of the information processing device 30 with the various tools 410 to 414 placed in the corresponding tool storage locations.

[0129] In this use example 11, as in the above-described use example 10, the coil switch 85 of the extension antenna device 80 is provided with another second terminal in addition to the second terminals 85b1 to 85b6 connected to the second coil portions 82A to 82F. Another second coil portion 82Z disposed outside the storage case 301 is connected to this other second terminal. This other second coil portion 82Z is ​​used to read information from the ID card 208 equipped with the RFID tag 40.

[0130] Therefore, in this use example 11, it is possible to read tool-related information from the RFID tags 40 of the tools 410 to 414 in the tool storage area 401 and ID information from the ID cards 208 of the tool users and tool managers using one extension antenna device 80 and one reader antenna 10. Therefore, compared to when these readings are performed using separate configurations, it is possible to realize an RFID tag reading system with a simpler configuration and lower cost.

[0131] [Embodiment 2] Next, an embodiment (hereinafter referred to as "Embodiment 2") in which the present invention is applied to an extension antenna device that extends the communication area (power transmission area) of a wireless power supply coil of a power supply device will be described. Here, "expanding" the communication area (hereinafter referred to as "power transfer area" in the second embodiment) means enabling power transfer (communication) at a location farther away than the power transfer area of ​​the wireless power supply coil, and includes expanding the size of the power transfer area and moving the power transfer area to a location farther away from the wireless power supply coil.

[0132] FIG. 32 is an explanatory diagram showing a usage mode in which the wireless power supply system 2 according to the second embodiment does not use an extension antenna device. The wireless power feeding system 2 of the second embodiment includes a power feeding device 500 and a power receiving device 510. A power feeding signal of a predetermined frequency flows from the power feeding device 500 to the power feeding coil 501 of the power feeding device 500. As a result, a magnetic field M as shown by the magnetic field lines in the figure is generated in the power feeding coil 501 by the current of the power feeding signal. When the power receiving coil 511 of the power receiving device 510 approaches the power feeding coil 501 in this state, the magnetic field M generated in the power feeding coil 501 passes through the power receiving coil 511 of the power receiving device 510, causing an induced current to flow in the power receiving coil 511 of the power receiving device 510, and the power receiving device 510 can receive power.

[0133] FIG. 33 is an explanatory diagram showing an example of a usage mode in which the extended antenna device 50 according to the present invention is used in the wireless power supply system 2 according to the second embodiment. The extended antenna device 50 of the second embodiment can have the same configuration as the extended antenna device 50 described in the first embodiment. The number of turns of each of the coils 51a, 52a of the first coil portion 51 and the second coil portion 52 is set appropriately depending on the frequency to be used. Furthermore, the thickness and material of the conductor wires of the first coil portion 51, the second coil portion 52 and the connecting wire 53 are set appropriately depending on the magnitude of the induced current to be generated.

[0134] When the extension antenna device 50 of the second embodiment is used, a magnetic field M generated in the power feeding coil 501 (source coil) by a signal of a predetermined frequency output from the power feeding device 500 generates an induced current signal i by electromagnetic induction in the first coil 51a of the first coil unit 51 arranged close to the power feeding coil 501. This induced current signal i flows into the second coil 52a of the second coil unit 52 connected to the first coil 51a via the connection wire 53. As a result, a magnetic field M corresponding to the induced current signal i corresponding to the signal from the power feeding device 500 is generated in the second coil 52a of the second coil unit 52.

[0135] In this state, when the power receiving coil 511 of the power receiving device 510 approaches the second coil section 52 of the extension antenna device 50, the magnetic field M generated in the second coil 52a of the second coil section 52 passes through the power receiving coil 511 (destination coil), and an induced current i flows in the power receiving coil 511. As a result, the induced current i is input to the power receiving device 510, and power is transmitted to the power receiving device 510.

[0136] According to the second embodiment, by using the extension antenna device 50, it is possible to transmit power from the power supply device 500 to the power receiving device 510 even at a location far from the power supply coil 501 of the power supply device 500. Therefore, it is possible to extend the power transmission area (communication area) of the power supply coil 501 of the power supply device 500.

[0137] Furthermore, according to the extension antenna device 50 of the second embodiment, as described above, the connection line 53 connecting the first coil 51a and the second coil 52a is a single connection line, and there is no need to suppress interference between the connection lines. Therefore, there is no need to use a shielded wire such as a coaxial cable as in the conventional extension antenna device, and it is possible to use an inexpensive connection line 53 that is resistant to bending and easy to route.

[0138] [Usage example 12] Next, an example of a usage mode of the extension antenna device 50 of the second embodiment (hereinafter, this example will be referred to as "Usage Example 12") will be described. FIG. 34 is a perspective view showing an extension antenna device 50 in this use example 12. As shown in FIG. In this use example 12, the smartphone 100 serving as a power receiving device is charged by the power feeding device 500 via the extension antenna device 50. According to this use example 12, it becomes possible to charge the smartphone 100 at another convenient location away from the power supply coil 501 of the power supply device 500, thereby improving convenience.

[0139] In this usage example 12, the smartphone 100 can be charged even if it is placed in the power transferable area of ​​the power feeding coil 501 (first coil section 51 of the extended antenna device 50) of the power feeding device 500. Therefore, it is possible to simultaneously charge the smartphone 100 placed in the power transferable area of ​​the power feeding coil 501 (first coil section 51 of the extended antenna device 50) of the power feeding device 500 and the smartphone 100 placed in the power transferable area of ​​the second coil section 52.

[0140] [Usage example 13] Next, another example of the usage of the extension antenna device 50 of the second embodiment (hereinafter, this example will be referred to as "Usage Example 13") will be described. FIG. 35 is an explanatory diagram showing an example of a wireless power supply system 2 that charges a smartphone 100 using an extension antenna device 50 in this thirteenth use example. FIG. 36 is an explanatory diagram showing the configuration of the extension antenna device 50 in this thirteenth use example. The extended antenna device 50 of this usage example 13 is configured using multiple (here, four) coil units including a first coil section 51 and a second coil section 52 connected to each other by a single connecting wire 53, thereby expanding the power transmission area and making it possible to simultaneously charge more smartphones 100.

[0141] In this example 13, the first coil portions 51A to 51D of the four coil units 50A to 50D are arranged in locations where they are connected to each other by electromagnetic induction. More specifically, as shown in Fig. 35, the first coil portions 51A to 51D of the four coil units 50A to 50D are arranged so that they overlap each other with their axes approximately parallel to each other. The second coil portions 52A to 52D are arranged in locations where they are not connected to each other by electromagnetic induction.

[0142] 35 , the first coil portions 51A to 51D of the four coil units 50A to 50D, which are arranged so as to overlap one another, are arranged in locations connected to the power feeding coil 501 of the power feeding device 500 by electromagnetic induction, specifically in a power transferable area (communicationable area) of the power feeding coil 501. As a result, a magnetic field generated in the power feeding coil 501 by a power feeding signal from the power feeding circuit 502 of the power feeding device 500 generates an induced current signal by electromagnetic induction in the coils of the first coil portions 51A to 51D of the four coil units 50A to 50D.

[0143] These induced current signals flow into the second coils of the second coil sections 52A to 52D via the respective connection lines 53A to 53D. Therefore, a magnetic field corresponding to the power supply signal from the power supply circuit 502 is generated in each of the second coil sections 52A to 52D of the four coil units 50A to 50D. The magnetic field generation area of ​​each of the second coil sections 52A to 52D becomes the respective power transmission area (communication area). Therefore, it is possible to simultaneously charge up to four smartphones 100 placed at charging locations that are within the power transmission area of ​​each of the second coil sections 52A to 52D.

[0144] Here, in this use example 13, a switch unit 504 is provided on each of the connection lines 53A to 53D of the four coil units 50A to 50D. This switch unit 504 is controlled by a control circuit 503 of the power supply device 500, and can switch on and off the transmission of a current signal on each of the connection lines 53A to 53D.

[0145] As a result, according to this usage example 13, for example, it is possible to turn on the switch of connection wire 53A only for the second coil unit (second coil unit 52A in the example of FIG. 35) of the charging point used by a user who has paid the charging fee for the smartphone, and charge the smartphone 100 of that user placed at the charging point of this second coil unit 52A. As a result, for the charging points of the other second coil units 52B to 52D, the switches of connection wires 53B to 53D are turned off, so that even if a smartphone 100 is placed at the charging points of these second coil units 52B to 52D without permission, charging will not occur.

[0146] As described above, according to this thirteenth use example, a plurality of power feeding points are provided for one power feeding coil 501 of power feeding device 500, and it becomes possible to control whether charging is possible at each power feeding point.

[0147] [Usage example 14] Next, still another example of the usage of the extension antenna device 50 of the second embodiment (hereinafter, this example will be referred to as "usage example 14") will be described. FIG. 37 is an explanatory diagram showing an example of a wireless power supply system 2 that charges electric vehicles 140, 141 using an extension antenna device 50 in this use example 14. In this use example 14, electric vehicles 140 and 141 serving as power receiving devices are charged by the power feeding device 500 via the extension antenna device 50.

[0148] According to this usage example 14, it is possible to simultaneously charge an electric vehicle 140 placed in the power transmission area of ​​the power supply coil 501 (first coil portion 51 of the extended antenna device 50) of the power supply device 500 and an electric vehicle 141 placed in the power transmission area of ​​the second coil portion 52.

[0149] [Usage example 15] Next, still another example of the usage of the extension antenna device 50 of the second embodiment (hereinafter, this example will be referred to as "Usage Example 15") will be described. FIG. 38 is an explanatory diagram showing an example of a wireless power supply system 2 that charges an electric vehicle 140 using an extension antenna device 50 in this use example 15. In this usage example 15, a moving electric vehicle 140 is charged by a power supply signal from a power supply coil 501 of a power supply device 500 installed outside the road at a plurality of charging points arranged along the travel lane.

[0150] In this use example 15, as in the above-described use example 14, an extended antenna device 50 including a plurality of coil units 50A to 50D is used. Specifically, the first coil portions 51A to 51D of each of the coil units 50A to 50D are arranged overlapping each other in the power transmission area (communication area) of the power supply coil 501 of the power supply device 500 installed outside the road. The second coil portions 52A to 52D of each of the coil units 50A to 50D are then arranged side by side along the driving lane on or within the road surface of the driving lane. As a result, when an electric vehicle 140 traveling in the driving lane passes over each of the second coil portions 52A to 52D, it is charged by the magnetic fields generated by each of the second coil portions 52A to 52D.

[0151] [Usage example 16] Next, still another example of the usage of the extension antenna device 50 of the second embodiment (hereinafter, this example will be referred to as "usage example 16") will be described. FIG. 39 is an explanatory diagram showing an example of a wireless power supply system 2 that charges an electric vehicle 140 using an extension antenna device 50 in this sixteenth use example. Like the above-mentioned Usage Example 15, Usage Example 16 is also an example of a case where a traveling electric vehicle 140 is charged by a power supply signal from a power supply coil 501 of a power supply device 500 installed outside the road at a plurality of charging points arranged along the travel lane.

[0152] In this use example 16, as in the above-described use example 4, multiple coil units 50A to 50D are magnetically coupled in series to increase the number of charging points. Specifically, in this use example 16, the power supply coil 501 of the power supply device 500 is placed on or within the road surface of a travel lane. As shown in FIG. 39, the first coil portion 51A of the first coil unit 50A is placed in the power transmission area (communication area) of the power supply coil 501. Furthermore, as shown in FIG. 35, the first coil portion 51B of the second coil unit 50B is placed in the power transmission area (communication area) of the second coil portion 52A of the first coil unit 50A. Furthermore, the first coil portion 51C of the third coil unit 50C is placed in the power transmission area (communication area) of the second coil portion 52B of the second coil unit 50B. As shown in FIG. 35, the first coil portion 51D of the fourth coil unit 50D is disposed in the power transferable area (communication area) of the second coil portion 52C of the third coil unit 50C.

[0153] In this usage example 16, a magnetic field generated in the power supply coil 501 by a power supply signal from the power supply device 500 generates an induced current signal by electromagnetic induction in the coil of the first coil section 51A of the first coil unit 50A. This induced current signal flows into the second coil 52a of the second coil section 52A via the connection line 53A. Therefore, in the second coil section 52A of the first coil unit 50A, a magnetic field corresponding to the induced current signal corresponding to the power supply signal from the power supply device 500 is generated, forming a power transmission area (communication area). Similarly, in the other coil units 50B to 50D, a magnetic field corresponding to the induced current signal corresponding to the power supply signal from the power supply device 500 is generated in each of the second coil sections 52B to 52D, forming a power transmission area (communication area).

[0154] 39, the first coil portion 51E of the fifth coil unit 50E is also arranged in the power transfer area (communication area) of the power supply coil 501. By magnetically coupling other coil units in series to the fifth coil unit 50E, it is possible to arrange charging points made up of the power transfer areas of the second coil portions on the opposite side of the power supply coil 501 from the coil units 50A to 50D.

[0155] In the case of the above-described use example 15, there is a limit to the length of the connection wire 53, so the second coil unit cannot be arranged at a charging location that is very far from one power supply coil 501. This makes it necessary to arrange more power supply coils 501. In contrast, according to the present use example 16, it is possible to arrange the second coil unit at a charging location that is farther away from one power supply coil 501. This makes the present use example 16 effective in reducing the number of arranged power supply coils 501.

[0156] [Usage example 17] Next, still another example of the usage of the extension antenna device 50 of the first embodiment (hereinafter, this example will be referred to as "Usage Example 17") will be described. 40(a) to 40(c) are explanatory diagrams showing an RFID tag reading system 1 using an extension antenna device 50 in this seventeenth example of use. FIG. 41 is an explanatory diagram showing the configuration related to one coil unit that constitutes the extended antenna device 50 in this use example 17. In this use example 17, the extended antenna device 50 is used for a guide map 600 installed in a facility such as a shopping center. Note that although the explanation here uses a shopping center guide map as an example, the invention can be applied to any facility.

[0157] The extended antenna device 50 in this usage example 17 includes five coil units 50A to 50E, each including a first coil portion 51 and a second coil portion 52 interconnected by a single connection line 53. The first coil portions 51A to 51E of each coil unit 50A to 50E are respectively disposed on the backside of five touch points located outside the map margin on the guide map 600. Information for identifying the corresponding store is displayed on the front side of each of the five touch points.

[0158] In the map section of the guide map 600, LED chips 602 equipped with LEDs as light-emitting elements are placed at the locations of stores corresponding to the touch points. As shown in Fig. 40(c), the LED chips 602 placed at the respective locations are placed within the magnetic field generation region of the second coil 52a of the second coil section 52A, which is connected to the first coil 51a of the first coil section 51A at the corresponding touch point via a single connection wire 53.

[0159] In this use example 17, as shown in Fig. 40(a), the user brings his / her smartphone 100 close to one of the touch points (first coil portions 51A to 51E) provided on the guide map 600. Here, an example will be described in which the smartphone 100 is brought close to the touch point of the first coil portion 51A of the first coil unit 50A as shown in Fig. 40(a).

[0160] In this case, a magnetic field generated by an NFC antenna coil (transmitter coil) in smartphone 100 generates an induced current signal i by electromagnetic induction in first coil 51a of first coil unit 51A at the touch point. This induced current signal i flows into second coil 52a of second coil unit 52A, which is connected to first coil 51a via connection wire 53. As a result, a magnetic field corresponding to the induced current signal corresponding to the signal from smartphone 100 is generated in second coil 52a of second coil unit 52A.

[0161] The magnetic field generated by the second coil 52a passes through the coil 602a (destination coil) of the LED chip 602 placed within the magnetic field generation region of the second coil 52a, causing an induced current i to flow through the LED 602b of the LED chip 602, causing the LED 602b to emit light. As a result, as shown in Figure 40(b), the location on the map of the store corresponding to the touch point is illuminated, making it possible to inform the user of the location of the store.

[0162] In the example of Figure 41, two LED chips 602 are placed within the magnetic field generation area of ​​the second coil 52a to ensure a large amount of light emission, but it is also possible to place only one LED chip 602, or three or more LED chips 602.

[0163] 41, an RFID tag 40 storing information about a corresponding store is also placed within the magnetic field generation region of the second coil portions 52A to 52E of each of the coil units 50A to 50E. As a result, in this use example 17, when a user brings their smartphone 100 close to a touch point (first coil portion 51A) provided on the guide map 600, information about the store corresponding to the touch point is read from the RFID tag 40 to the smartphone 100. As a result, the information about the store corresponding to the touch point is displayed on the smartphone 100 and provided to the user.

[0164] Here, RFID tags 40 that store information about stores corresponding to each touch point are placed within the communication range of second coil portions 52A-52E of coil units 50A-50E in which first coil portions 51A-51E are placed at the respective touch points, but this is not limiting. For example, RFID tags 40 that store information about stores corresponding to each touch point may be placed within the communication range of first coil portions 51A-51E that are placed at the respective touch points.

[0165] The above description is merely an example, and each of the following aspects provides unique effects. [First aspect] The first aspect is an extended antenna device 50, 70, 80 that transmits an induced current signal i generated in a first coil 51a by electromagnetic induction between a source coil (e.g., coil 11 of a reader antenna 10, power supply coil 501 of a power supply device 500) and a destination coil (e.g., coil 41 of an RFID tag 40, power receiving coil 511 of a power receiving device 510) by electromagnetic induction from a second coil 52a connected to the first coil via a connection wire 53, 73, 83, and characterized in that one end of the winding of the first coil and one end of the winding of the second coil are connected to each other by a single connection wire, and the other end of the winding of the first coil and the other end of the winding of the second coil are both open. In conventional extension antenna devices, the connecting wire connecting the first coil and the second coil has a loop structure in which both ends of the windings of each coil are connected to each other. Therefore, the first coil and the second coil are connected by at least two connecting wires. This type of extension antenna device is used, for example, in near-field wireless communication such as RFID (Radio Frequency Identification) tags and contactless power supply (wireless power supply), and the induced current signal generated in the first coil due to electromagnetic induction with the transmitter coil is a relatively high-frequency signal. Therefore, in conventional extension antenna devices that connect the first coil and the second coil with at least two connecting wires, it is necessary to suppress interference between the connecting wires, so shielded wires such as coaxial cables are used for each connecting wire (see, for example, Patent Document 1). As a result, the connecting wires connecting the first coil and the second coil are expensive and have problems such as being difficult to route due to their weak resistance to bending, etc. In the extension antenna device of this aspect, one end of the winding of the first coil and one end of the winding of the second coil are connected to each other by a single connecting wire, and the other end of the winding of the first coil and the other end of the winding of the second coil are both open, forming a non-loop structure. Therefore, the connecting wire connecting the first coil and the second coil is a single connecting wire, and there is no need to suppress interference between the connecting wires. This eliminates the need to use a shielded wire such as a coaxial cable as in conventional extension antenna devices, making it possible to use an inexpensive connecting wire that is resistant to bending and easy to route. Generally, circuits that transmit relatively high-frequency signals (hereinafter referred to as "high-frequency signals") used in near-field wireless communication, contactless power supply (wireless power supply), and the like require a loop structure for proper signal transmission. In fact, coils connected to electrical circuits (electrical circuits that process signals), such as transmission coils in RFID readers and RFID tags (coils that transmit and receive signals by magnetically coupling with the outside) and transmission coils in power supply devices and power receiving devices, have both ends of the coil winding connected to an electrical circuit, forming a loop structure. However, the first and second coils in an extended antenna device are not connected to such an electrical circuit; they only need to allow an induced current signal generated in the first coil by electronic induction to flow to the second coil via a connecting wire. Focusing on this point, the present inventor developed an extended antenna device with a non-loop configuration in which the first and second coils are connected by a single connecting wire, and confirmed that it actually functions as an extended antenna device.

[0166] [Second mode] A second aspect is characterized in that in the first aspect, the transmitter coil is a data transmission coil (for example, the coil 11 of the reader antenna 10) that transmits data by electromagnetic induction. This makes it possible to provide an extension antenna device for data communication in which the connecting wire connecting the first coil and the second coil is inexpensive, and is resistant to bending and other factors, making it easy to route.

[0167] [Third aspect] A third aspect is the second aspect, characterized in that the first coil and the second coil are configured to be tuned to the communication frequency of the data transmission from the transmitting coil. This allows for a wider communication area and stable data communication.

[0168] [Fourth aspect] A fourth aspect is the first aspect, characterized in that the transmitter coil is a wireless power supply coil that transmits power by electromagnetic induction. This makes it possible to provide an extension antenna device for wireless power supply that uses an inexpensive connecting wire connecting the first coil and the second coil, and that is resistant to bending and other factors, making it easy to route.

[0169] [Fifth mode] A fifth aspect is the fourth aspect, characterized in that the first coil and the second coil are configured to be tuned to a transmission frequency of power from the transmitting coil. This allows for a wider communication area (power transmission area) and stable wireless power supply.

[0170] [Sixth aspect] A sixth aspect is the device according to any one of the first to fifth aspects, characterized in that the single connecting wire is an unshielded wire. This makes it possible to provide an extension antenna device in which the connecting wire connecting the first coil and the second coil is inexpensive, and is resistant to bending and the like, making it easy to route.

[0171] [Seventh aspect] The seventh aspect is characterized in that, in any of the first to sixth aspects, it has a plurality of coil units 50A to 50F including the first coil and the second coil connected to each other by the single connecting wire, and the coil constituting one coil unit among the plurality of coil units and the coil constituting another coil unit among the plurality of coil units are arranged at a location where they are connected to each other by electromagnetic induction. This makes it possible to further expand the communication area and move the communication area to a more distant location than an extension antenna device made up of a single coil unit.

[0172] [Eighth aspect] The eighth aspect is characterized in that, in the seventh aspect, the multiple coil units are three or more coil units, and the coils included in at least three of the three or more coil units are arranged in locations where they are connected to each other by electromagnetic induction, and the other coils included in the at least three coil units are arranged in locations where they are not connected to each other by electromagnetic induction. This makes it possible to further expand the communicable area compared to an extension antenna device configured with a single coil unit.

[0173] [Ninth aspect] A ninth aspect is characterized in that, in the seventh or eighth aspect, the multiple coil units are three or more coil units, and are arranged so that the destination coil connected by electromagnetic induction to the second coil of a first coil unit among the three or more coil units is the first coil of the second coil unit among the three or more coil units, and the destination coil connected by electromagnetic induction to the second coil of the second coil unit is the first coil of a third coil unit among the three or more coil units. This makes it possible to extend the communication range to a farther location than an extended antenna device made up of a single coil unit.

[0174] [Tenth aspect] A tenth aspect is characterized in that, in any of the first to ninth aspects, a third coil 54 is provided in which a part of the single connecting wire is wound. This makes it possible to further expand the communicable area even with an extension antenna device made up of a single coil unit.

[0175] [Eleventh aspect] An eleventh aspect is characterized in that, in any of the first to tenth aspects, a connection switch (e.g., coil switch 85) is provided on the single connection line 83, which switches the connection destination of a connection terminal (e.g., first terminal 85a) to one of a plurality of connected terminals (e.g., second terminals 85b1 to 85b6), and one of the first coil and the second coil connected to each other by the single connection line is connected to the connection terminal of the connection switch, and the other coil consists of a plurality of coils each connected to the plurality of connected terminals of the connection switch. This allows the coils connected to the respective connected terminals and the counterpart coils magnetically coupled by electromagnetic induction to be processed separately for each of the coils. [Explanation of symbols]

[0176] 1: RFID tag reading system 2: Wireless power supply system 10: Reader antenna 11: Coil 20: RFID reader 21: Communication cable 30: Information processing device 31: Communication cable 40: RFID tag 41: Coil 42: NFC chip 50: Extended antenna device 50A~50F: Coil unit 51, 51A to 51F: First coil section 51a: First coil 51b: Core 51c: Other end of winding 52, 52A to 52F: Second coil section 52a: Second coil 52b: Core 52c: Other end of winding 53, 53A~53F: Connection wire 54: Case 54a: Hinge 55: Mounting table 55a: Smartphone installation area 55b: Tag table section 55c: Post 61~64: Coil 65: Connection line 70: Extended antenna device 71: First coil section 72: Second coil section 73: Connection line 74: Third coil section 80: Extended antenna device 81: First coil section 82A~82F, 82Z: Second coil section 83, 83A~83F, 83Z: Connection wire 85: Coil switch 85a: First terminal 85b1~85b6: Second terminal 86: Cable 100: Smartphone 100a: Screen 101: Wearing band 120: Robot arm 121: Pedestal 122A~122E: Joint mechanism 123A~123D: Arm section 124: End effector 130: Storage box 140, 141: Electric vehicles 200: Robot arm 201: Medicine Pack 202: Sheet 203: Medication tray 204: Small box 205: Name tag 206, 207: XY table 208: ID card 300: Storage System 301: Storage case 302: Opening and closing door 303: Automatic locking mechanism 304: Camera 305A~305F: Weight sensor 310,311:Medicines 400: Tool management system 401: Tool storage area 410~414: Tools 500: Power supply device 501: Power supply coil 502: Power supply circuit 503: Control circuit 504: Switch section 510: Power receiving device 511: Receiving coil 600: Guide map 602: LED chip [Prior art documents] [Patent documents]

[0177] [Patent Document 1] Patent No. 5069025 [Patent Document 2] Patent No. 6323312

Claims

1. An extension antenna device that transmits an induced current signal generated in a first coil by electromagnetic induction between a source coil and the first coil from a second coil connected to the first coil via a connection wire to a destination coil by electromagnetic induction, one end of the winding of the first coil and one end of the winding of the second coil are connected to each other by a single connecting wire; The extension antenna device is characterized in that the other end of the winding of the first coil and the other end of the winding of the second coil are both open.

2. 2. The extension antenna device according to claim 1, The extension antenna device is characterized in that the transmitter coil is a data transmission coil that transmits data by electromagnetic induction.

3. 3. The extension antenna device according to claim 2, The extended antenna device is characterized in that the first coil and the second coil are configured to be tuned to a communication frequency of the data transmission from the source coil.

4. 2. The extension antenna device according to claim 1, The extension antenna device is characterized in that the transmitter coil is a wireless power supply coil that transmits power by electromagnetic induction.

5. 5. The extension antenna device according to claim 4, An extended antenna device, characterized in that the first coil and the second coil are configured to be tuned to the transmission frequency of power from the transmitting coil.

6. 6. The extension antenna device according to claim 1, The extended antenna device is characterized in that the single connecting line is an unshielded line.

7. 6. The extension antenna device according to claim 1, a plurality of coil units including the first coil and the second coil connected to each other by the single connecting wire; An extended antenna device characterized in that a coil constituting one of the plurality of coil units and a coil constituting another of the plurality of coil units are arranged at a location where they are connected to each other by electromagnetic induction.

8. 8. The extension antenna device according to claim 7, the plurality of coil units are three or more coil units, An extended antenna device characterized in that the coils included in at least three of the three or more coil units are arranged in locations where they are connected to each other by electromagnetic induction, and the other coils included in the at least three coil units are arranged in locations where they are not connected to each other by electromagnetic induction.

9. 8. The extension antenna device according to claim 7, the plurality of coil units are three or more coil units, An extended antenna device characterized in that the destination coil connected by electromagnetic induction to the second coil of a first coil unit among the three or more coil units is the first coil of a second coil unit among the three or more coil units, and the destination coil connected by electromagnetic induction to the second coil of the second coil unit is the first coil of a third coil unit among the three or more coil units.

10. 6. The extension antenna device according to claim 1, An extension antenna device comprising a third coil wound around a portion of the single connecting wire.

11. 6. The extension antenna device according to claim 1, a connection switch for switching the connection destination of a connection terminal to one of a plurality of connected terminals is provided on the single connection line; one of the first coil and the second coil, which are connected to each other by the single connection line, is connected to the connection terminal of the connection switch; The other coil comprises a plurality of coils respectively connected to the plurality of connection terminals of the connection switch.

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