JP2012163363A - Identification tag, identification tag set, frequency division type identification terminal, and identification method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an identification tag and an identification terminal which are excellent in power utilization efficiency, are simply configured, and are manufactured at a low cost.SOLUTION: An identification terminal 2 is inquiry means, and when a specified frequency f1 is set to an oscillation circuit 22, an induction field 230 of the frequency f1 is generated in a primary side transformer 23, and the primary side transformer 23 and a secondary side transformer 11 are electromagnetically coupled through the induction field 230. The secondary side transformer 11 has a capacitor connected in parallel and constitutes a resonance circuit. When a resonance frequency of the resonance circuit is f1, an LED light emitting part 13 emits light on the basis of the power of the output of the resonance circuit. The LED light emitting part 13 comprises two LEDs connected in opposite polarity with each other. By selecting the oscillation frequency of the oscillation circuit 22, the identification tag having a specified resonance frequency is identified.

Description

  The present invention relates to an identification tag system that enables identification of an article with a simple configuration, and in particular, a passive identification tag and an identification tag set for supplying power to an identification tag by electromagnetic coupling between an interrogator and an identification tag, and frequency division The present invention relates to a type identification terminal and an identification method.

  As a passive identification tag system, there is a search system described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2004-101483). The search system (100) of Patent Document 1 includes a transmitting device (110) that transmits an electromagnetic wave having a predetermined frequency and a tag (120) that resonates when receiving the electromagnetic wave having the predetermined frequency ( Description of paragraphs 0021, 0022, 0033, 0037, etc. and FIG. 1). The transmission device (110) includes a transmission antenna 115 that transmits an electromagnetic wave having a frequency of several tens of MHz and a power of about 1 watt (paragraph 0033, FIG. 2). The tag (120) includes an LC resonance circuit 123 that resonates with the electromagnetic wave. The LC resonance circuit 123 includes a coil 121 and a capacitor 122 (paragraph 0037, FIG. 5). The tag (120) includes a light emitting diode (125), and when the electromagnetic wave having the resonance frequency of its own LC resonance circuit 123 is received from the transmitting device (110), causes the light emitting diode (125) to emit light and The location of the search object (200) to which the tag (120) is attached is notified (paragraphs 0022, 0038, FIGS. 4 and 5). In other words, the search system described in Patent Document 1 described above employs a so-called radio wave reception type as a power supply method.

  As another passive identification tag system, there is an RFID (Radio Frequency IDentification) system that includes a reader / writer and a card, and supplies power and transmits information by electromagnetic coupling between the two. The RFID system is adopted as a commuter commuter pass under the name Suica (registered trademark) by, for example, East Japan Railway Company. In the RFID system used in the watermelon, the reader / writer and the card are coupled in two systems, that is, a power supply system and an information transmission system. The coupling between the reader / writer and the card in each of the power supply system and the information transmission system is electromagnetic coupling. That is, the RFID system employs a so-called electromagnetic induction type as a power supply system. The reader / writer and the card have antenna coils for a power supply system and an information transmission system, respectively. That is, two antenna coils are provided in the reader / writer and two antenna coils are provided in the card. In the information transmission system, the reader / writer and the card are each provided with a modulation / demodulation circuit. The electromagnetic coupling between the reader / writer and the card is performed at a high frequency of 13.56 MHz.

JP 2004-101483 A

  As described above, the search system described in Patent Document 1 employs a radio wave reception type power supply method, and generates electromagnetic waves with a frequency of several tens of MHz and about 1 watt from the antenna (115) of the transmission device (110). By transmitting, electric power is supplied to the LC resonance circuit (123) of the tag (120). In the radio wave reception type power supply method, the power use efficiency is extremely low compared to the electromagnetic induction type power supply method. In other words, the search system described in Patent Document 1 has low power use efficiency, inevitably increasing the size of the transmitting device (110) as an inquiry device for identifying a tag, and reducing power consumption. There is a drawback that it is difficult, and there is a problem to be solved about the power use efficiency.

  On the other hand, as described above, since the RFID system employs an electromagnetic induction type as a power supply system, the power utilization efficiency is considerably high, and a power utilization efficiency of 60 to 98% can be achieved. Regarding the method of wireless power supply, from the August 2009 issue of Monthly Telecommunications, "Practical roadmap and impact of next-generation wireless technology [5th]" Wireless power supply "Resonance principle 2m ahead" This article has been reprinted in the Internet business network.jp magazine, dated 2010.05.27, with a sentence by Tomoharu Ota. The above power utilization efficiency data is also published as a chart in the article by Tomoharu Ota (in this table, “Source: Partially modified Toshiba materials” is added).

  As described above, since the RFID method employs an electromagnetic induction type as a power supply method, the power use efficiency is excellent. However, the reader / writer and the card are coupled to each other in two systems of a power supply system and an information transmission system. Therefore, two antenna coils are required for each of the reader / writer and the card, and a modulation / demodulation circuit is required for each of the reader / writer and the card. In other words, the RFID system has an unavoidable drawback that the configuration is complicated and expensive, and there is a problem to be solved regarding the complexity of the configuration and the manufacturing cost.

  SUMMARY OF THE INVENTION In order to solve such problems, an object of the present invention is to provide an identification tag, an identification tag set, a frequency division type identification terminal, and an identification method that are excellent in power utilization efficiency, simple in configuration, and can be manufactured at low cost.

  In order to solve the above-described problems, the identification tag and the identification tag set, the frequency division type identification terminal, and the identification method according to the present invention mainly adopt the following characteristic configuration.

(1) The identification tag according to the present invention is an identification tag that responds only when it has the characteristic when it receives an inquiry from the inquiry means whether it has the predetermined characteristic,
A resonance circuit, and light emitting means for emitting light based on the output power of the resonance circuit,
The resonant circuit has a secondary coil that is coupled to the primary coil by electromagnetic induction when placed in an induction electromagnetic field generated by a primary coil of the inquiry means;
The characteristic is a resonant frequency of the resonant circuit;
The response is light emission of the light emitting means.

(2) The identification tag set according to the present invention is an identification tag described in (1) above, and includes a plurality of identification tags attached to a plurality of identification objects with the resonance frequencies different from each other. It is characterized by.

(3) Further, the frequency division type identification terminal according to the present invention is an identification terminal as an inquiry unit for inquiring whether or not the identification tag has a predetermined characteristic.
A primary coil that generates an induction electromagnetic field and is coupled to the secondary coil by electromagnetic induction when the secondary coil of the identification tag is placed in the induction electromagnetic field;
An oscillation circuit for supplying AC power to the primary coil,
The oscillation circuit includes a frequency setting unit, and generates the AC power at a frequency set by the frequency setting unit. The frequency setting unit is selected from a plurality of frequencies set to different values. The oscillation frequency of the oscillation circuit is set to a single frequency.

(4) Also, the frequency division type identification method according to the present invention attaches an identification tag to an identification object, inquires from the inquiry means whether or not the identification tag has a predetermined characteristic, and only has the characteristic. In the method of identifying the identification object by the identification tag responding to
An oscillating circuit that oscillates at an arbitrary frequency selected from different oscillating frequencies causes an alternating current to flow through a primary coil provided in the inquiry means, and the identification tag is applied to an electromagnetic induction electric field of the primary coil. The secondary coil is positioned, and when the resonant circuit including the secondary coil resonates with the electromagnetic induction electric field, the light emitting means provided in the identification tag is used as the response with the AC power induced in the resonant circuit. Determining that the resonance frequency of the resonance circuit is previously associated with the oscillation frequency of the oscillation circuit by emitting light, and identifying the identification target with the identification tag by the determination; Features.

  According to the present invention, it is possible to provide an identification tag and an identification tag set, a frequency division type identification terminal, and an identification method that are excellent in power utilization efficiency, simple in configuration, and can be manufactured at low cost.

It is a block diagram which shows the structure of the identification tag which is embodiment of this invention, and a frequency division type identification terminal. It is a block diagram which shows the structure of the identification tag which is another embodiment of this invention, and a frequency division type identification terminal. It is a perspective view which shows the external appearance of the identification tag shown in FIG. It is a perspective view which shows the external appearance of the frequency division type identification terminal shown in FIG. It is a circuit diagram of the LED light emission part 13 in the identification tag shown in FIG. It is a flowchart which shows the frequency division type identification method by the identification tag and frequency division type identification terminal which were shown in FIG.

  Preferred embodiments of an identification tag, an identification tag set, a frequency division type identification terminal, and an identification method according to the present invention will be described below with reference to the accompanying drawings.

(Features of the present invention)
Prior to the description of the embodiments of the present invention, an outline of the features of the present invention will be described first. In the frequency division type identification method according to the present invention, an identification tag is attached to an identification object, an inquiry as to whether or not the identification tag has a predetermined characteristic is performed from a frequency division type identification terminal as an inquiry means, and the characteristic is obtained. This is a method for identifying an object to be identified by responding to the identification tag only when it has it. In this frequency division type identification method, an alternating current is passed through a primary coil provided in the inquiry means by an oscillation circuit that oscillates at an arbitrary frequency selected from mutually different oscillation frequencies, and the primary coil A secondary coil of the identification tag is positioned in the electromagnetic induction electric field of the AC, and the identification tag is provided with AC power induced in the resonance circuit when the resonance circuit including the secondary coil resonates with the electromagnetic induction electric field. By causing the light emitting means to emit light as the response, it is determined that the resonance frequency of the resonance circuit is associated with the oscillation frequency of the oscillation circuit in advance, and the determination-attached tag with the identification tag Identify the object to be identified.
Furthermore, the present invention provides an identification tag, an identification tag set, and a frequency division type identification terminal that are used to implement this frequency division type identification method.

(Configuration example of embodiment of the present invention)
Next, the configuration of the embodiment of the identification tag and the frequency division type identification terminal according to the present invention will be described with reference to FIG. 1 to FIG. 6 and the embodiment of the frequency division type identification method will be described together. The identification tag set includes a plurality of identification tags, and the resonance frequencies of the resonance circuits in the plurality of identification tags are different from each other.

  FIG. 1 is a block diagram showing a configuration of a passive identification tag system including an identification tag and a frequency division type identification terminal according to an embodiment of the present invention. This identification tag system includes an identification tag 1 and an identification terminal 2. The identification tag 1 includes a secondary transformer 11 and an LED light emitting unit (LED: light emitting diode) 13. The secondary transformer 11 corresponds to the secondary coil described above. A capacitor is connected in parallel to the secondary transformer 11, and the secondary transformer 11 and the capacitor constitute a resonance circuit. The identification terminal 2 includes a power source 21, an oscillation circuit 22, and a primary side transformer 23. The primary transformer 23 corresponds to the primary coil described above. The oscillation circuit 22 includes a resonance circuit serving as the frequency setting means described above, and a dial 22a for setting the resonance frequency of the resonance circuit. An example of the dial 22a is shown in FIG. An arbitrary frequency within a predetermined range is selected by the rotation of the dial 22a, and the oscillation circuit 22 oscillates at that frequency.

  The power source 21 is a DC power source made of a battery, and supplies DC power 210 to the oscillation circuit 22. The oscillation circuit 22 receives the DC power 210, oscillates at the frequency set by the dial 14 (the frequency is now assumed to be f1), and outputs the AC power 220 of several hundred kHz (for example, 200 kHz). The AC power 220 is several hundred watts or less, for example, 100 watts. The primary transformer 23 receives AC power 220 and generates an induction electromagnetic field 230. The induction electromagnetic field 230 is an alternating electromagnetic field that vibrates at a frequency f 1 and is electromagnetically coupled to the secondary transformer 11.

  As described above, a capacitor is connected in parallel to the secondary transformer 11, but the capacitor is not shown in FIG. The resonance frequency of the resonance circuit including the secondary transformer 11 and its capacitor is determined by the inductance of the secondary transformer 11 and the capacitance of the capacitor. The resonance frequency of this resonance circuit is a unique value for each identification tag. This resonance frequency is a characteristic of the aforementioned identification tag. If the resonance circuit resonates at the frequency f1 of the induction electromagnetic field 230, the identification tag 1 having the resonance circuit is specified with the characteristic that the resonance frequency is f1. Therefore, the identification tag 1 specified by the characteristic that “the resonance frequency is f1” is distinguished from an identification tag having a resonance circuit of another resonance frequency. Thus, the identification tag 1 specified by the characteristic “resonance frequency is f1” is (uniquely) identified as one thing.

  A resonance circuit including the secondary transformer 11 and a capacitor induces a voltage that peaks when resonating with the input induction electromagnetic field 230. An alternating induced current 110 based on this voltage is supplied to the LED light emitting unit 13. FIG. 5 is a circuit diagram showing the LED light emitting unit 13. The LED light emitting unit 13 is formed by connecting two LEDs D1 and D2 in parallel with opposite polarities. An AC induced voltage, which is the output of the resonance circuit (consisting of the secondary transformer 11 and the capacitor), is applied to terminals a and b. The induced current 110 is alternating current, but D1 and D2 are connected in parallel with opposite polarities, so that one LED to which a forward voltage is applied is energized according to the alternating polarity of the induced voltage. The voltage between the terminals of the energized LED is very small (the voltage between terminals a and b is very small) and is much lower than the withstand voltage of the other LED to which the reverse voltage is applied, so the other LED to which the reverse voltage is applied is destroyed. It will never be done. Therefore, even if a rectifier circuit is not provided between the secondary transformer 11 and the LED light emitting unit 13, the LED of the LED light emitting unit 13 is not destroyed by the reverse voltage. Further, when an alternating induction voltage is applied between the terminals a and b, D1 and D2 blink alternately, but since the oscillation frequency of the oscillation circuit 22 is several hundred kHz, D1 and D2 are continuously lit. It is visually recognizable.

  As described above, a peak voltage when resonating with the input induced electromagnetic field 230 is induced in the resonance circuit composed of the secondary transformer 11 and the capacitor, and an AC induced current 110 based on the induced voltage is generated. The LED light emitting unit 13 is supplied to cause the LED light emitting unit 13 to emit light. Therefore, when the frequency f1 of the induction electromagnetic field 230 (that is, the oscillation frequency of the oscillation circuit 22) coincides with the resonance frequency of the resonance circuit, an induction current 110 sufficient to cause the LED light emitting unit 13 to emit light is generated. When the frequency f1 of the field 230 does not match the resonance frequency of the resonance circuit, the AC power 220 of the output of the oscillation circuit 22 or the primary transformer is set so that the induced current 110 is not large enough to cause the LED light emitting unit 13 to emit light. An induction electromagnetic field 230 based on electromagnetic coupling between the secondary transformer 11 and the secondary transformer 11 is designed. The resonance frequency width of the resonance circuit when it is determined that the frequency f1 of the induction electromagnetic field 230 matches the resonance frequency of the resonance circuit is a range in which the induced voltage of the output of the resonance circuit is 70% from the peak.

  As described above, in the embodiment of FIG. 1, the LED light emitting unit 13 emits light only when the oscillation frequency f1 of the oscillation circuit 22 matches the resonance frequency of the resonance circuit of the identification tag 1. By selecting the frequency f, only the identification tag attached to the object being searched for is allowed to emit light, and the object can be identified from other objects.

  FIG. 3 is a perspective view showing an embodiment in which an attachment band 15 is attached to the identification tag 1 of FIG. Reference numeral 130 schematically indicates light output from the LED light emitting unit 13. By attaching the attachment band 15 to the identification tag 1, it becomes easy to attach the identification tag 1 to the article to be identified.

  FIG. 4 is a perspective view showing the identification terminal 2 of FIG. Reference numeral 2a denotes a main body in which the power source 21 and the oscillation circuit 22 are housed. Reference numeral 22 a indicates a dial for setting the oscillation frequency of the oscillation circuit 22. Reference numeral 26 denotes a probe in which the primary transformer 23 is built. Reference numeral 25 denotes a cable for passing AC power 220.

  By setting the rotation angle of the dial 22a, the oscillation circuit 22 can be oscillated at a frequency manually selected from within a predetermined frequency band. The oscillation frequency of the oscillation circuit 22 is set by operating the dial 22a so as to coincide with the resonance frequency of the resonance circuit of the identification tag 1 being searched (consisting of the secondary transformer 11 and a capacitor connected in parallel). By doing so, the LED light emission part 13 of the identification tag 1 can be light-emitted. As described above, in the embodiment of FIG. 1, a desired product with an identification tag can be easily found by setting the oscillation frequency of the oscillation circuit 22. A correspondence table (resonance frequency / identification object correspondence table) showing the correspondence between the resonance frequency of the resonance circuit of the identification tag 1 and the identification object to which the identification tag 1 is attached is created in advance, and the operator of the identification terminal 2 With reference to the correspondence table, the oscillation frequency of the oscillation circuit 22 is set.

  FIG. 2 is a block diagram showing a modification of the passive identification tag system shown in FIG. The identification tag system of FIG. 2 includes an identification tag 1a and an identification terminal 2. The identification tag system of FIG. 1 is different from the identification tag system in the same identification terminal. In the identification tag 1a, the rectifier circuit 12 is provided between the secondary transformer 11 and the LED light emitting unit 13a, and the LED light emitting unit 13a is configured by a single LED. In the identification tag 1a of FIG. 2, the rectifier circuit 12 converts the induced current 110 output from the secondary transformer 11 into a direct current 120, and supplies the direct current 120 to the LED light emitting unit 13a. Therefore, the LED light emitting unit 13a is configured by a single LED so that a forward current flows with the direct current 120.

  FIG. 6 is a flowchart showing a frequency division type identification method based on the identification tag method (consisting of an identification tag and a frequency division type identification terminal) shown in FIG. As shown in step S1, the oscillation frequency f of the identification terminal 2 is set to the resonance frequency of the target identification tag 1. The primary transformer 23 (probe 26 in FIG. 4) of the identification terminal 2 is brought close to the identification tag 1 (step S2). The frequency of the induction electromagnetic field 230 output from the primary side transformer 23 is compared with the resonance frequency of the resonance circuit of the identification tag 1 (parallel circuit of the secondary side transformer 11 and the capacitor) (step S3). As a result, when the frequencies do not match (step S4), the LED light emitting unit 13 of the identification tag 1 does not emit light. If the frequencies match, the LED light emitting unit 13 of the identification tag 1 emits light (step S5). By repeating this operation, the identification tag 1 attached to the search object can be identified.

  As described above and described in detail, the present embodiment is excellent in power utilization efficiency because power is supplied from the identification terminal 2 to the identification tag 1 by electromagnetic induction coupling. In addition, this embodiment can be manufactured at low cost because the configuration is simpler than that of an RFID that requires coupling of two systems, that is, a power supply system and an information transmission system, between an identification terminal and an identification tag. Furthermore, if this embodiment is used, an operator (operator) can identify a specific object simply by visually observing whether or not the LED light-emitting unit emits light, so that it is written on the tag. Since it is not necessary to read the information with the eyes, the burden on the operator is considerably small.

  As an example of the usage scene of this embodiment, there can be cited a data center in which a large number of servers and LAN cables having substantially the same appearance are arranged in a narrow space. When performing maintenance while operating these devices / equipment, it is essential to find a specific server or LAN cable without error. The identification tag of this embodiment is attached in advance to each server or LAN cable. The resonance frequencies of these identification tags are different from each other. In this way, the identification tag is attached to the object in advance, and the frequency corresponding to the specific object is operated by operating the frequency setting dial of the identification terminal while referring to the table indicating the correspondence between each object and the resonance frequency. A specific object can be easily identified by causing the oscillation circuit 22 to oscillate at f.

    The configuration of the preferred embodiment of the present invention has been described above. However, it should be noted that such embodiments are merely examples of the present invention and do not limit the present invention in any way. Those skilled in the art will readily understand that various modifications and changes can be made according to a specific application without departing from the gist of the present invention. For example, the identification tag can be grasped as an identification tag set and handled integrally with a plurality of identification tags attached to a plurality of identification objects with different resonance frequencies.

DESCRIPTION OF SYMBOLS 1,1a Identification tag 2 Identification terminal 2a Main part 11 which accommodated the power supply 21 and the oscillation circuit 22 Secondary transformer 12 Rectifier circuit 13, 13a LED light emission part 15 Attachment band 21 Power supply 22 Oscillation circuit 22a Frequency setting dial 23 Primary transformer 25 AC Electric power 220 cable 26 Probe 110 incorporating the primary transformer 23 Inductive current 120 DC current 130 Light 210 output from the LED light-emitting unit 13 DC power 220 AC power 230 Inductive electromagnetic fields D1, D2 LED
a and b terminals

Claims (10)

In an identification tag that responds only when it has the characteristic when it receives an inquiry from the inquiry means whether it has the predetermined characteristic,
A resonance circuit, and light emitting means for emitting light based on the output power of the resonance circuit,
The resonant circuit has a secondary coil that is coupled to the primary coil by electromagnetic induction when placed in an induction electromagnetic field generated by a primary coil of the inquiry means;
The characteristic is a resonant frequency of the resonant circuit;
The identification tag, wherein the response is light emission of the light emitting means. The light emitting means comprises a plurality of light emitting diodes connected in parallel,
At least one of the plurality of light emitting diodes is connected to a polarity opposite to that of the other light emitting diodes;
The identification tag according to claim 1, wherein the plurality of light emitting diodes emit light by AC power that is an output of the resonance circuit. A rectifier circuit that converts AC power output from the resonant circuit into DC power;
The identification tag according to claim 1, wherein the light emitting means is a light emitting diode that emits light by the DC power received from the rectifier circuit.   The identification tag according to claim 1, further comprising an attachment band for attaching to an identification object.   An identification tag according to any one of claims 1 to 3, wherein the identification tag includes a plurality of identification tags attached to a plurality of identification objects with different resonance frequencies. Tag set. In the identification terminal as an inquiry means for inquiring whether or not the identification tag has a predetermined characteristic,
A primary coil that generates an induction electromagnetic field and is coupled to the secondary coil by electromagnetic induction when the secondary coil of the identification tag is placed in the induction electromagnetic field;
An oscillation circuit for supplying AC power to the primary coil,
The oscillation circuit includes a frequency setting unit, and generates the AC power at a frequency set by the frequency setting unit. The frequency setting unit is selected from a plurality of frequencies set to different values. An oscillation frequency of the oscillation circuit is set to a single frequency. A frequency division type identification terminal.   The frequency division type identification terminal according to claim 6, wherein the primary coil is built in a probe and connected to the oscillation circuit via a cable.   The frequency setting means can set at least any one selected from the resonance frequencies different from each other in each identification tag in the identification tag set according to claim 5. The frequency division type identification terminal according to any one of the above. An identification tag is attached to the identification object, an inquiry about whether or not the identification tag has a predetermined characteristic is made from the inquiry means, and the identification tag responds only when it has the characteristic. In the method of identifying:
An oscillating circuit that oscillates at an arbitrary frequency selected from different oscillating frequencies causes an alternating current to flow through a primary coil provided in the inquiry means, and the identification tag is applied to an electromagnetic induction electric field of the primary coil. The secondary coil is positioned, and when the resonant circuit including the secondary coil resonates with the electromagnetic induction electric field, the light emitting means provided in the identification tag is used as the response with the AC power induced in the resonant circuit. Determining that the resonance frequency of the resonance circuit is previously associated with the oscillation frequency of the oscillation circuit by emitting light, and identifying the identification target with the identification tag by the determination; A characteristic frequency division type identification method. A plurality of identification tags which are attached to a plurality of identification objects by causing the oscillation circuit to oscillate one frequency arbitrarily selected from a plurality of predetermined oscillation frequencies so that the resonance frequencies are different from each other. The frequency division type identification method according to claim 9, wherein one of them is identified.

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