RFID tag system

Abstract

To construct an inexpensive system that supplies electricity to an RFID tag reader.SOLUTION: An RFID tag system includes an RFID tag reader, and an environmental power generation unit which supplies electricity to an RFID tag reader.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to RFID tag systems. [Background technology]

[0002] As disclosed in Patent Document 1, RFID (Radio Frequency Identifier) ​​tags are sometimes used for individual identification. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2016-099876 Summary of the Invention [Problem to be solved by the invention]

[0004] When reading a passive RFID tag that does not have a battery, it is necessary to bring an RFID tag reader close to the RFID tag and transmit electromagnetic waves from the RFID tag reader to the RFID tag. To solve this problem, active RFID tags with built-in thermoelectric conversion elements have been devised, as described in Patent Document 1. However, the active type increases costs and loses the advantages of the passive type, such as low cost and disposability. There is a demand for a system that can acquire data wirelessly like the active type, while taking advantage of the passive type's advantages of low cost and disposability.

[0005] The present disclosure aims to supply power to an RFID tag reader and build an inexpensive system. [Means for solving the problem]

[0006] According to the present disclosure, there is provided an RFID tag system including an RFID tag reader and an energy harvesting unit that supplies power to the RFID tag reader. [Effects of the Invention]

[0007] According to the present disclosure, power is supplied to an RFID tag reader inexpensively. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram schematically illustrating an RFID tag system according to an embodiment. [Figure 2] FIG. 2 is a diagram schematically illustrating a wireless reader terminal according to the embodiment. [Figure 3] FIG. 3 is a perspective view schematically showing a thermoelectric power generation module according to an embodiment. [Figure 4] FIG. 4 is a block diagram showing the wireless reading terminal according to the embodiment. [Figure 5] FIG. 5 is a flowchart showing the operation of the RFID tag system according to the embodiment. [Figure 6] FIG. 6 is a schematic diagram showing a wireless reading terminal according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the embodiments. The components of the embodiments described below can be combined as appropriate. In addition, some components may not be used.

[0010] [RFID tag system] 1 is a diagram schematically illustrating an RFID tag system 1 according to an embodiment. The RFID tag system 1 includes a wireless reader terminal 2 and a management computer 3. A plurality of wireless reader terminals 2 are provided. The management computer 3 communicates wirelessly with each of the plurality of wireless reader terminals 2 via a communication system 4.

[0011] In the embodiment, the wireless reading terminal 2 is installed in an industrial machine 5. An example of the industrial machine 5 is hydraulic equipment. The wireless reading terminal 2 includes an RFID tag reading device. The wireless reading terminal 2 reads an RFID tag attached to a replacement part of the industrial machine 5. In the example shown in FIG. 1 , one wireless reading terminal 2 is provided for each of the multiple industrial machines 5. Note that multiple wireless reading terminals 2 may be provided for one industrial machine 5.

[0012] [Wireless sensor terminal] 2 is a diagram schematically illustrating a wireless reader terminal 2 according to an embodiment. As shown in FIG. 2, the wireless reader terminal 2 includes a housing 6, an energy harvesting unit 7, an RFID tag reader 8, a controller 10, and a wireless communication device 13.

[0013] The housing 6 contains the energy harvesting unit 7 and the controller 10. The housing 6 is arranged so as to be in contact with the industrial machine 5. The housing 6 has a heat receiving unit 6A and a heat dissipating unit 6B. The heat receiving unit 6A is in contact with the surface of the industrial machine 5.

[0014] The energy harvesting unit 7 functions as a power source for the wireless reading terminal 2. The energy harvesting unit 7 supplies power to each of the RFID tag reader 8, the controller 10, and the wireless communication device 13. The energy harvesting unit 7 generates power based on changes in the environment in which the energy harvesting unit 7 is placed. In the embodiment, the energy harvesting unit 7 is a thermoelectric power generation module. The thermoelectric power generation module generates power based on heat generated by the industrial machine 5. In the following description, the energy harvesting unit 7 will be referred to as the thermoelectric power generation module 7 where appropriate.

[0015] The thermoelectric power generation module 7 generates electricity using the Seebeck effect. The industrial machine 5 functions as a heat source for the thermoelectric power generation module 7. The thermoelectric power generation module 7 is disposed between a heat receiving portion 6A and a heat dissipation portion 6B. When one end surface of the thermoelectric power generation module 7 is heated, a temperature difference is created between the one end surface and the other end surface of the thermoelectric power generation module 7. The temperature difference created between the one end surface and the other end surface of the thermoelectric power generation module 7 causes the thermoelectric power generation module 7 to generate electricity. In the embodiment, one end surface of the thermoelectric power generation module 7 is connected to the heat receiving portion 6A via a heat transfer member 6C. The other end surface of the thermoelectric power generation module 7 is connected to the heat dissipation portion 6B. The heat receiving portion 6A receives heat from the industrial machine 5. The heat from the heat receiving portion 6A is transferred to the thermoelectric power generation module 7 via the heat transfer member 6C. The heat dissipation portion 6B receives heat from the thermoelectric power generation module 7. The heat from the heat dissipation portion 6B is dissipated into the atmospheric space surrounding the wireless reading terminal 2.

[0016] The RFID tag reader 8 reads an RFID tag 9 attached to a replacement part 50 of the industrial machinery 5. An oil filter is an example of the replacement part 50. However, the replacement part 50 of the industrial machinery 5 is not limited to an oil filter. The RFID tag 9 is a passive type that does not have a battery. The RFID tag 9 is attached to the replacement part 50.

[0017] The RFID tag reader 8 is driven by the power generated by the thermoelectric power generation module 7. The RFID tag reader 8 is disposed outside the housing 6. The RFID tag reader 8 is supported on at least a part of the industrial machine 5. The RFID tag reader 8 and the controller 10 are connected via a cable 17. The thermoelectric power generation module 7 supplies power to the RFID tag reader 8 via the controller 10 and the cable 17.

[0018] The RFID tag reader 8 is disposed at a first position Pa of the industrial machine 5. The thermoelectric power generation module 7 housed in the housing 6 is disposed at a second position Pb of the industrial machine 5. The first position Pa is defined around a replacement part 50 to which an RFID tag 9 is attached. The second position Pb is defined at a position where the temperature is higher than that of the first position Pa. The second position Pb is defined near the hydraulic motor.

[0019] 2, the first position Pa and the second position Pb are adjacent to each other, but the first position Pa and the second position Pb may be sufficiently separated from each other. The length of the cable 17 may be adjusted based on the distance between the first position Pa and the second position Pb.

[0020] The controller 10 controls the wireless reader terminal 2. The controller 10 includes a circuit board 11 and a microcomputer 12 mounted on the circuit board 11. The circuit board 11 is supported by the housing 6 via a support member 14.

[0021] The microcomputer 12 is driven by the electric power generated by the thermoelectric power generation module 7 .

[0022] The wireless communication device 13 is mounted on the circuit board 11. The thermoelectric power generation module 7 supplies power to the wireless communication device 13. The wireless communication device 13 is driven by the power generated by the thermoelectric power generation module 7. The wireless communication device 13 communicates with the management computer 3. In the embodiment, the wireless reading terminal 2 and the management computer 3 communicate wirelessly (OTA: Over The Air) technology. The wireless communication device 13 wirelessly transmits read data from the RFID tag reader 8 to the management computer 3.

[0023] [Thermoelectric power generation module] FIG. 3 is a perspective view schematically illustrating a thermoelectric power generation module 7 according to an embodiment. The thermoelectric power generation module 7 includes p-type thermoelectric semiconductor elements 7P, n-type thermoelectric semiconductor elements 7N, a first electrode 71, a second electrode 72, a first substrate 73, and a second substrate 74. The p-type thermoelectric semiconductor elements 7P and the n-type thermoelectric semiconductor elements 7N are alternately arranged in a plane parallel to the surface of the first substrate 73. The first electrode 71 is connected to each of the p-type thermoelectric semiconductor elements 7P and the n-type thermoelectric semiconductor elements 7N. The second electrode 72 is connected to each of the p-type thermoelectric semiconductor elements 7P and the n-type thermoelectric semiconductor elements 7N. One end face of the p-type thermoelectric semiconductor elements 7P and one end face of the n-type thermoelectric semiconductor elements 7N are connected to the first electrode 71. The other end face of the p-type thermoelectric semiconductor elements 7P and the other end face of the n-type thermoelectric semiconductor elements 7N are connected to the second electrode 72. The first electrode 71 is connected to a first substrate 73. The second electrode 72 is connected to a second substrate 74.

[0024] Each of the p-type thermoelectric semiconductor element 7P and the n-type thermoelectric semiconductor element 7N includes, for example, a BiTe-based thermoelectric material. Each of the first substrate 73 and the second substrate 74 is formed of an electrically insulating material such as ceramic or polyimide.

[0025] Heating the first substrate 73 creates a temperature difference between one end and the other end of each of the p-type thermoelectric semiconductor element 7P and the n-type thermoelectric semiconductor element 7N. When a temperature difference is created between one end and the other end of the p-type thermoelectric semiconductor element 7P, holes move in the p-type thermoelectric semiconductor element 7P. When a temperature difference is created between the other end and one end of the n-type thermoelectric semiconductor element 7N, electrons move in the n-type thermoelectric semiconductor element 7N. The p-type thermoelectric semiconductor element 7P and the n-type thermoelectric semiconductor element 7N are connected via a first electrode 71 and a second electrode 72. A potential difference is created between the first electrode 71 and the second electrode 72 due to the holes and electrons. The potential difference created between the first electrode 71 and the second electrode 72 causes the thermoelectric power generation module 7 to generate power. A lead wire 75 is connected to the first electrode 71. The thermoelectric power generation module 7 outputs power via the lead wire 75.

[0026] [controller] 4 is a block diagram showing a wireless reader terminal 2 according to an embodiment. The wireless reader terminal 2 includes a thermoelectric power generation module 7, a capacitor 70, an RFID tag reader 8, a controller 10, and a wireless communication device 13.

[0027] The controller 10 includes a power supply control unit 15 and an acquisition unit 16. The wireless communication device 13 includes a transmission unit .

[0028] The capacitor 70 stores the power generated by the thermoelectric power generation module 7. When the amount of power stored in the capacitor 70 reaches or exceeds a predetermined value, the power is released from the capacitor 70. The power released from the capacitor 70 is consumed by each of the RFID tag reader 8, the controller 10, and the wireless communication device 13. That is, the power released from the capacitor 70 is used to drive each of the RFID tag reader 8, the controller 10, and the wireless communication device 13. After the power is released from the capacitor 70, the capacitor 70 stores again the power generated by the thermoelectric power generation module 7.

[0029] In the embodiment, a power storage state in which the power generated by the thermoelectric power generation module 7 is stored in the power storage device 70 and a power consumption state in which the power stored in the power storage device 70 is consumed by each of the RFID tag reader 8, the controller 10, and the wireless communication device 13 are alternately repeated. The power storage device 70 stores power intermittently. Each of the RFID tag reader 8, the controller 10, and the wireless communication device 13 is driven intermittently.

[0030] The power supply control unit 15 supplies the power discharged from the capacitor 70 to the RFID tag reader 8. The power supply control unit 15 includes a drive circuit that drives the RFID tag reader 8 based on the power supplied from the thermoelectric power generation module 7. The power supply control unit 15 may be configured by at least a part of the microcomputer 12.

[0031] The acquiring unit 16 acquires read data from the RFID tag reader 8. As described above, in the embodiment, the RFID tag reader 8 is driven intermittently. The acquiring unit 16 acquires detection data output from the RFID tag reader 8 during one driving period of the RFID tag reader 8. The acquiring unit 16 includes a detection circuit that acquires the read data from the RFID tag reader 8. Note that the acquiring unit 16 may be configured by at least a part of the microcomputer 12.

[0032] The transmitter 21 wirelessly transmits the read data of the RFID tag reader 8 to the management computer 3. As described above, the wireless communication device 13 is driven intermittently. The transmitter 21 transmits the read data of the RFID tag reader 8 at regular time intervals based on the power discharged from the capacitor 70.

[0033] The management computer 3 receives the read data of the RFID tag reader 8 transmitted from the transmitter 21 of the wireless reader terminal 2 .

[0034] [RFID tag system operation] 5 is a flowchart showing the operation of the RFID tag system 1 according to the embodiment. When the industrial machine 5 is driven and a temperature difference is created between one end face and the other end face of the thermoelectric power generation module 7, the thermoelectric power generation module 7 generates power. In the embodiment, the thermoelectric power generation module 7 is disposed at the second position Pb of the industrial machine 5 where the temperature increases when the industrial machine 5 is driven. Therefore, the thermoelectric power generation module 7 can generate sufficient power.

[0035] The power generated by the thermoelectric power generation module 7 is stored in the capacitor 70. When the amount of power stored in the capacitor 70 reaches or exceeds a predetermined value, power is released from the capacitor 70. The RFID tag reader 8, the controller 10, and the wireless communication device 13 are each driven based on the power released from the capacitor 70 (step SA1).

[0036] The RFID tag reader 8 is disposed at a first position Pa of the industrial machine 5 around the replacement part 50. Therefore, when the replacement part 50 is replaced, the RFID tag reader 8 can read the RFID tag 9 attached to the replacement part 50. When the replacement part 50 is attached to the industrial machine 5, the RFID tag reader 8 can read the RFID tag 9 attached to the replacement part 50.

[0037] If the replacement part 50 is a conforming product (genuine product), the conforming product will have a genuine RFID tag 9 attached. If the replacement part 50 is a non-conforming product (counterfeit product), the non-conforming product will not have an RFID tag attached. Furthermore, even if the non-conforming product has an RFID tag attached, the identification data indicated by the RFID tag attached to the non-conforming product will be different from the genuine identification data indicated by the RFID tag attached to the conforming product. Therefore, the RFID tag reader 8 can determine whether the replacement part 50 is a conforming product by reading the RFID tag 9.

[0038] When the RFID tag reader 8 reads a genuine RFID tag 9, the read data of the RFID tag reader 8 is acquired by the acquiring unit 16 (step SA2).

[0039] The transmitter 21 wirelessly transmits the read data from the RFID tag reader 8 to the management computer 3 (step SA3).

[0040] The management computer 3 wirelessly receives the read data from the RFID tag reader 8. The management computer 3 stores the read data from the RFID tag reader 8 (step SB1).

[0041] The management computer 3 can manage, for example, the start time of use of a replacement part 50 based on the read data from the RFID tag reader 8. Read data is transmitted to the management computer 3 from a plurality of wireless reader terminals 2. The management computer 3 can centrally manage the replacement parts 50 of a plurality of industrial machines 5.

[0042] [effect] As described above, according to the embodiment, the thermoelectric power generation module 7, which is an environmental power harvester, is used as the power source for the RFID tag reader 8. This allows for the construction of an inexpensive system that can acquire data wirelessly like an active type, while taking advantage of the advantages of a passive type that is inexpensive and disposable.

[0043] In the embodiment, the RFID tag reader 8 is fixed around the replacement part 50. This allows the RFID tag reader 8 to smoothly read the RFID tag 9 attached to the replacement part 50 after replacement when the replacement part 50 is replaced.

[0044] The thermoelectric power generation module 7 supplies power to the RFID tag reader 8 via the controller 10 and the cable 17. This makes it possible to easily adjust the relative positions of the thermoelectric power generation module 7 and the RFID tag reader 8.

[0045] The data read by the RFID tag reader 8 is wirelessly transmitted to the management computer 3 by the wireless communication device 13. This allows the management computer 3 to manage the replacement parts 50.

[0046] [Other embodiments] FIG. 6 is a schematic diagram showing a wireless reader terminal 2 according to an embodiment. As shown in FIG. 6, a thermoelectric power generation module 7 may be connected to a plurality of RFID tag readers 8. Each of the plurality of RFID tag readers 8 is connected to the thermoelectric power generation module 7 via a cable 17. For example, if one industrial machine 5 has a plurality of replacement parts 50, an RFID tag reader 8 is disposed near each of the plurality of replacement parts 50. This allows each of the plurality of replacement parts 50 to be determined as being compatible. The thermoelectric power generation module 7 is disposed, for example, near a hydraulic motor. This allows the thermoelectric power generation module 7 to generate sufficient power.

[0047] In the above-described embodiment, the RFID tag reader 8 is arranged outside the housing 6 and is connected to the controller 10 via the cable 17. The RFID tag reader 8 may also be arranged inside the housing 6.

[0048] In the above-described embodiment, the wireless reading terminal 2 is arranged in the industrial machine 5. The wireless reading terminal 2 may be arranged in a device different from the industrial machine 5. Examples of the device include a motor or a generator.

[0049] In the above-described embodiment, the energy harvester 7 may be, for example, a solar power generator, a vibration power generator, or an electromagnetic wave power generator. [Explanation of symbols]

[0050] 1...RFID tag system, 2...wireless reading terminal, 3...management computer, 4...communication system, 5...industrial machinery, 6...housing, 6A...heat receiving section, 6B...heat dissipation section, 6C...heat transfer member, 7...thermoelectric power generation module (environmental power generation section), 7N...n-type thermoelectric semiconductor element, 7P...p-type thermoelectric semiconductor element, 8...RFID tag reader, 9...RFID tag, 10...controller, 11...circuit board, 12...microcomputer, 13...wireless communication device, 14...support member, 15...power supply control section, 16...acquisition section, 17...cable, 21...transmission section, 50...replacement part, 70...capacitor, 71...first electrode, 72...second electrode, 73...first board, 74...second board, 75...lead wire.

Claims

1. A controller accommodated in a housing disposed in a device; an RFID tag reader disposed on the device outside the housing; an energy harvesting unit accommodated in the housing disposed in the device and supplying power to an RFID tag reader; a cable connecting the RFID tag reader and the controller; the energy harvesting unit supplies power to the RFID tag reader via the controller and the cable; the RFID tag reader reads an RFID tag attached to a replacement part of the equipment; RFID tag system.

2. the energy harvesting unit includes a thermoelectric power generation module; The RFID tag system of claim 1 .

3. the energy harvesting unit is connected to a plurality of the RFID tag readers; 3. The RFID tag system according to claim 1.

4. a wireless communication device that wirelessly transmits read data from the RFID tag reader; the energy harvesting unit supplies power to the wireless communication device; The RFID tag system according to any one of claims 1 to 3.

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