JP7133232B2 - Parts management card and parts management device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a parts management card for managing parts used to manufacture an assembly, and more particularly to a parts management card capable of accurately managing parts inventory in an assembly production line.

A system has been developed in which an RF tag is attached to each part stored in a warehouse to manage the inventory of each part. However, in order to manage the parts inventory accurately, it is necessary to manage the parts inventory on the assembly production line as well as the management in the warehouse.

When managing the inventory of parts by attaching RF tags to individual parts, the cost of RF tags and the cost of attaching them to the parts is high. A system has been developed to do so.

For example, Patent Document 1 (WO2008/038434) discloses an invention of a parts management program, a parts management method, and a parts management apparatus capable of accurately managing parts inventory in a manufacturing line.

In the invention described in Patent Document 1, in order to manage the parts on the production line, the withdrawal unit of the parts management system starts manufacturing based on the parts configuration information in the parts configuration information storage unit and the production order in the production order DB. The number of parts used in the assembled product, the number of parts used, and the supply box are specified, and the number of parts used from the number of parts in the supply box data corresponding to the specified supply box is withdrawn to update the supply box DB. Further, the tracking unit detects entry and exit of the supply box to the line based on the information of the UHF band RFID tag, and the state reflection unit reflects the movement of the supply box in the supply box DB. In addition, the extraction unit writes the update log of the material supply box DB to the material supply box log storage unit, and the operation monitoring unit detects the excess or deficiency of the material supply pace and the line of the material supply box based on the update log of the material supply box log storage unit. It monitors the retention of parts and the number of parts. Also, the editing section notifies the warehouse management system based on the update log of the supply box log storage section.

In Patent Document 2 (Japanese Patent Application Laid-Open No. 2009-51601), in a system for renting reusable transportation equipment in physical distribution, after the administrator (for example, the lender) first enters the warehouse at one delivery base of the user, , it is disclosed that items are often lost in the process of repeatedly entering and leaving the warehouse between multiple delivery bases of the user, which has a great impact on the system.

In the management system for a carrier described in Patent Document 2, when the carrier 11 delivered from the management side to the user side is unloaded from the management side, a wireless RF tag attached with an identification code written by a data writer or a printed tag is attached. The management card 5 or other identification medium affixed to the equipment is managed individually by the identification code of the management card 5, etc., and the data on the returned carrier is deleted by the user using the storage information file sent from the management side. It is configured so that only

Patent Document 3 (Japanese Unexamined Patent Application Publication No. 2011-118572) discloses a card-type RFID kanban used in a parts arrangement system using an EDI system.

In the card-type RFID kanban described in Patent Document 3, an orderer 100 generates kanban data 12 and transmits it to an EDI server computer 101 . The contractor 200 receives the kanban data 12 from the EDI server computer 101 and supplies it to the data writer 14 . The data writer 14 writes the Kanban data 12 into the recycled erased Kanban 24, issues the Kanban 16, and attaches it to the parts 18 to be delivered. The orderer 100 uses the antenna 72 to read the parts management card attached to the delivered parts 18 . The kanban 16 is formed into a standard size RFID card and held in a holding portion 52 provided on the outer surface of a parts box 200 in which the parts 18 are stored when delivered to the orderer 100 .

WO2008/038434 Japanese Patent Application Laid-Open No. 2009-51601 JP 2011-118572 A

However, in the invention of Patent Document 1, the RFID tag is attached to the supply box with a spacer interposed therebetween. Also, a parts pick-up Kanban is attached to the supply box. Therefore, the installation of those RFID tags and Kanban cards is troublesome. Furthermore, it is not possible to manage the parts housed in the metal parts box.

In the invention of Patent Document 2, a management card with an IC tag attached is attached to the carrier, and the management card cannot be easily removed from the carrier. Furthermore, even in Patent Document 2, it is not possible to manage the parts housed in the metal parts box.

Patent Document 3 discloses the use of a metal component box, but in order to suppress the reflection and absorption of radio waves by the metal box, a radio wave absorbing sheet is attached to the back surface of the Kanban board. is needed. Therefore, there is a drawback that the communication distance by the reader is short.

SUMMARY OF THE INVENTION It is a primary object of the present invention to provide a parts management card capable of managing parts contained in a parts box and having a long communication distance by a reader.
Another object of the present invention is to provide a parts management card capable of managing parts housed in a parts box even if the parts box is made of metal and having a long communication distance by a reader.

(1)
A parts management card according to one aspect is a parts management card detachably held in a holding part attached to the outer surface of a parts box in which parts are housed, comprising: a parts management card main body made of an insulator; The RF tag embedded in the parts management card main body and the part box side of the RF tag are inserted into the parts management card body or the parts with the insulating layer of the parts management card body interposed between the RF tag and the RF tag. and a metal plate disposed on the outer surface of the management card body.
In addition, the card body is mainly made of one or more kinds of electrically insulating resins such as polypropylene, ABS, polyethylene terephthalate, polyimide, and polyvinyl chloride, materials having insulating properties such as hard paper board or hard glass, or It can be formed by molding into a plate shape using a composite material in which materials are combined.
An RF tag includes at least an antenna and an IC chip that operates based on radio waves transmitted from a reader. are connected to each other.

In this case, since the waveguide plate provided on the RF tag of the card and the metal plate are electrically connected via a constant capacitance, the metal plate can be used as part of the antenna. Therefore, it is possible to have a large opening area and improve the sensitivity of the RF tag. Therefore, when the component management card is held by the holding portion attached to the outer surface of the component box, it is possible to read the RF tag which is omnidirectional and has a long communication distance.

(2)
A parts management card according to a second aspect of the invention is a parts management card detachably held by a holding portion attached to the outer surface of a metal parts box in which parts are stored, and the parts are made of an insulating material. It has a management card body and an RF tag embedded in the part management card body, and the RF tag includes at least an antenna and an IC chip that operates based on radio waves transmitted from a reader. , is held by the holding portion so that the waveguide plate provided on the RF tag and the component box are electrostatically coupled.

In this case, when the parts management card is held by the holding part attached to the outer surface of the metal parts box, the holding part is so arranged that the waveguide plate provided on the RF tag of the card and the parts box are electrostatically coupled. The parts box can be used as part of the antenna. Therefore, it is possible to have a large opening area and improve the sensitivity of the RF tag. Moreover, reading by the reading device is also possible from the periphery of the parts box.

(3)
A parts management card according to a third aspect of the invention is the parts management card according to the invention of one aspect, wherein the parts box is made of metal, and the waveguide provided on the RF tag and the parts box are electrostatically coupled. Alternatively, it may be held by the holding portion.

In this case, when the parts management card is held by the holding part of the parts box, the metal plate of the card and the parts box are electrically connected, and the waveguide plate of the card and the metal plate are electrically connected as described above. Communication performance is stabilized because connection is made via a constant capacity.
(4)
A parts management card according to a fourth invention is the parts management card according to the first aspect to the third invention, wherein the waveguide plate may be an antenna.

In this case, the structure of the RF tag can be simplified and radio waves from the reader can be efficiently received.
(5)
A parts management card according to a fifth aspect of the invention is the parts management card according to the first aspect to the third aspect of the invention, wherein the waveguide plate may be a waveguide element provided in an antenna.

In this case, the structure of the RF tag can be simplified and radio waves from the reader can be efficiently received.

(6)
A parts management card according to a sixth invention is the parts management card according to one aspect to the fifth invention, wherein the antenna has a first main surface and a second main surface opposite to the first main surface. a first waveguide element provided on the first main surface; a second waveguide element provided on the second main surface; and a second waveguide element provided on a side surface of the insulating base material. and a power feeding portion having one end electrically connected to a side surface of the insulating base, one end electrically connected to the first waveguide element, and the other end electrically connected to the second waveguide element. a plate-like inverted F antenna configured to receive radio waves transmitted from the reading device by the insulating base material, the first waveguide element, the second waveguide element, the feeding portion, and the short-circuiting portion; An inductor pattern composed of a first waveguide element, a short-circuiting part, a second waveguide element, and a feeder part, and a capacitor composed of the first waveguide element, the second waveguide element, and an insulating base material make it possible to generate radio waves. A resonant circuit that resonates in a frequency band may be configured.

In this case, the resonance circuit enables the plate-shaped inverted F antenna to receive radio waves transmitted from the reader with high sensitivity, so that the reading performance of the RF tag can be improved. Since the power supply voltage generated by the IC chip connected to the antenna can be increased, radio waves from the reader can be efficiently received.

(7)
A parts management card according to a seventh invention is the parts management card according to the sixth invention, wherein the outer peripheral distance of the waveguide element is λ/4, λ /2, 3λ/4, or 5λ/8.
In this case, the resonance frequency of the plate-shaped inverted F antenna can be easily set.

(8)
A parts management card according to an eighth invention is the parts management card according to the fifth invention, wherein the antenna comprises a resonant circuit that resonates in the frequency band of radio waves due to the inductor pattern and the internal capacitance of the IC chip. may

In this case, the inlet part and the antenna are formed by bonding, and a resonance circuit is formed by the electrostatic capacitance inside the IC chip and the inductor pattern. As a result, miniaturization or thinning can be achieved.

(9)
A parts management card according to a ninth invention is the parts management card according to the eighth invention, wherein the peripheral distance of the antenna is other than nλ (n is an integer ), λ/4, λ/2, 3λ/4, and 5λ/8.

In this case, the peripheral distance of the antenna is designed to correspond to any one of wavelength λ other than nλ (n is an integer), λ/4, λ/2, 3λ/4, and 5λ/8. As a result, the communication sensitivity can be dramatically improved, and omnidirectional radio waves can be received.

(10)
A parts management card according to a tenth invention is the parts management card according to the eighth and ninth inventions, wherein at least the IC chip and the inductor pattern portion may be wrapped with a non-conductor.

In this case, since at least the IC chip and the inductor pattern are covered with a non-conductor, short-circuiting of the IC chip and inductor pattern can be prevented even if they come into contact with the conductor.

(11)
A parts management card body according to an eleventh aspect of the present invention is a parts management card according to one aspect to a tenth aspect of the invention, wherein the parts management card may be a Kanban used in a parts management system.

In general, in a parts management system such as the Kanban production method, a paper Kanban is created based on Kanban information, and the parts to be delivered are delivered with a paper Kanban attached. When the action is performed, the receipt and acceptance inspection are completed, and the parts are consumed, the paper Kanban is discarded as a discarded Kanban.
A huge amount of paper is consumed every day because paper kanbans are used for each part required for daily production. In order to reduce the load on the environment, it is required to reduce the amount of discarded paper Kanban.
According to the eighth invention, the movement of parts is managed using the UHF band RFID tag held in the holding part of the parts box, and the parts inventory on the line is reduced by managing the number of parts for each parts box. can be managed accurately. In addition, it is possible to provide RFID kanbans that can be used efficiently, and to reduce the disposal of paper kanbans.

(12)
A parts management apparatus according to a twelfth aspect of the present invention includes a parts management device comprising a metal parts box in which parts are stored, and a parts management card detachably held by a holding section attached to the outer surface of the parts box. A device, wherein the parts management card has an insulating parts management card body and an RF tag embedded in the parts management card body, and the RF tag includes at least an antenna and a reader. and an IC chip that operates based on radio waves transmitted from the RF tag, and when the parts management card is held in the holding part, the waveguide plate provided on the RF tag and the parts box are electrostatically coupled. is.

In this case, when the parts management card is held by the holding part attached to the outer surface of the metal parts box, the waveguide plate provided on the RF tag of the card and the parts box are electrostatically coupled, so that the parts A box can be used as part of the antenna. Therefore, it is possible to have a large opening area and improve the sensitivity of the RF tag. Moreover, reading by the reading device is also possible from the periphery of the parts box. Therefore, it is not necessary to attach a radio wave absorbing sheet to the back surface of the card as described in Patent Document 3, and the manufacturing cost of the card can be reduced.

FIG. 2 is a schematic perspective view showing an example of a state in which a parts management card according to the first embodiment is held by a holding portion of a parts box; FIG. 4 is a schematic perspective view after the card is held by the holding portion; FIG. 4 is a schematic cross-sectional view of a main part showing an example of a state in which the parts management card according to the first embodiment is held in the parts box; It is a schematic perspective view of a parts box according to another embodiment. FIG. 5 is a schematic cross-sectional view of main parts showing an example of a state in which a parts management card is held in a holding portion of the parts box shown in FIG. 4 ; FIG. 2 is a schematic perspective view of the parts management card shown in FIG. 1; FIG. 7 is a schematic cross-sectional view of part of the parts management card shown in FIG. 6; FIG. 4 is a schematic perspective view showing an example of an RF tag on the surface side; FIG. 4 is a schematic perspective view showing an example of an RF tag on the back side; FIG. 2 is a schematic developed view showing an example of an RF tag; 2 is a diagram showing an example of an equivalent circuit of a parts management card to which the metal plate of FIG. 1 is attached; FIG. 2 is a diagram showing an example of an equivalent circuit of a metal parts box holding the parts management card of FIG. 1; FIG. FIG. 11 is a schematic perspective view of a main part showing an example of an RF tag used for a parts management card according to still another embodiment; FIG. 14 is a schematic plan view of the RF tag shown in FIG. 13; FIG. 14 is a schematic plan view of the antenna section of the RF tag shown in FIG. 13; 14 is a schematic enlarged view of a circuit member of the RF tag shown in FIG. 13; FIG. 14 is a schematic perspective view of the parts management card in which the RF tag shown in FIG. 13 is embedded; FIG. FIG. 11 is a schematic perspective view showing an example of the front surface side of an RF tag according to still another embodiment; FIG. 19 is a schematic perspective view showing an example of the back side of the RF tag shown in FIG. 18; FIG. 19 is a schematic perspective view showing an example of an antenna of the RF tag shown in FIG. 18; FIG. 19 is a schematic exploded view of the antenna of the RF tag shown in FIG. 18; FIG. 4 is a schematic diagram showing the results of an RF tag reading experiment; FIG. 10 is a schematic cross-sectional view of an insulating base material used in an RF tag of still another embodiment; FIG. 10 is a schematic cross-sectional view of an insulating base material used in an RF tag of still another embodiment; FIG. 4 is a schematic diagram showing another example of an RF tag; FIG. 26 is a schematic diagram showing an example of the relationship between the frequency band and communication distance of the RF tag of FIG. 25; FIG. 26 is a schematic diagram showing another example of the RF tag of FIG. 25; FIG. 26 is a schematic diagram showing an example of the structure of the RF tag of FIG. 25; FIG. 26 is a schematic diagram showing an example of the structure of the RF tag of FIG. 25;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same reference numerals are given to the same parts. Moreover, in the case of the same reference numerals, their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

(First embodiment)
FIG. 1 is a schematic perspective view showing an example of a state in which a parts management card 210 according to this embodiment is held in a holding section 230 of a parts box 200, and FIG. 2 shows a parts management card 210 according to this embodiment. FIG. 4 is a schematic cross-sectional view of main parts showing an example of a state in which the business card 210 is held by the holding portion 230;
The parts management card 210 according to the present embodiment is detachably held by a holding part 230 attached to the outer surface of the parts box 200 in which parts are stored.

(Parts box 200)
The parts box 200 is a box formed in a size large enough to accommodate one or more parts. For example, it may be a metal plate made of metal such as steel or aluminum, a metal mesh, a metal box made by processing a metal pipe, or a resin box, a wooden box, a cardboard box, or the like. There may be.
Furthermore, it may be a box made of a composite member in which those materials are combined. The surface of the parts box 200 may be coated with a film such as an antirust treatment, an oxide layer, or a resin layer.
The parts box 200 also includes a parts tray and a box with a lid.
In this embodiment, the parts box 200 is formed of a metal box with an open top, having a bottom plate 202 and four side plates 204, as shown in FIGS. A holding portion 230 is attached to the outer surface of the side plate 204 of the parts box 200 .

The configuration of the holding unit 230 is not particularly limited as long as it can hold the parts management card (hereinafter also simply referred to as card) 210 . For example, the holding portion 230 can be configured by forming a sheet into a bag shape.
In this embodiment, as shown in FIGS. 1 to 3, the holding part 230 is formed by bonding the left and right edges and the lower edge of a transparent or translucent plastic sheet to the outer surface of the side plate 204 of the parts box 200. It is formed in the shape of a bag with an upper opening.
An opening 232 is formed above the holding portion 230 between the side plate 204 and the sheet of the holding portion 230 , and the card 210 can be inserted into the holding portion 230 through the opening 232 and held.

The holding parts 230 are normally attached to the outside of the opposing side plates 204 of the parts box 200, but the holding parts 230 are provided on the outer surface of one, three or four side plates 204 of the parts box 200. may
The holding part 230 is not limited to a bag-like one, and may have various forms and arbitrary shapes as long as it has a function of holding, temporarily fixing, or fixing the card 210 to the outer surface of the side plate 204 of the parts box 200. There may be.

Next, FIG. 4 is a schematic perspective view of a parts box 200 according to another embodiment, and FIG. 5 shows a state in which a parts management card 210 is held by a holding portion 230 of the parts box 200 shown in FIG. FIG. 2 is a schematic cross-sectional view of main parts showing an example of .

As shown in FIGS. 4 and 5, the holding portion 230 includes a pair of L-shaped locking members 240, 240 fixed to the side plate 204 at a predetermined interval, and a side plate 240 below the locking member 240. and a retaining member 242 secured to 204 . In this case, a space for holding the card 210 is formed by the pair of locking members 240 , 240 , the holding member 242 and the outer surface of the side plate 204 .

(Parts management card 210)
6 is a schematic perspective view of the parts management card 210 shown in FIG. 1, and FIG. 7 is a schematic cross-sectional view of part of the parts management card 210 shown in FIG.

As shown in FIGS. 6 and 7, the parts management card 210 includes a parts management card body 220 made of resin and an RF signal embedded in the parts management card body 220 (hereinafter also simply referred to as the card body). a tag 100;
The size and shape of the parts management card 210 are set so that it can be detachably held in the holding portion 230 . In this embodiment, the card body 220 is formed of a substantially rectangular resin plate.

The card body 220 of this embodiment is formed by molding one or more types of electrically insulating resin such as polypropylene, ABS, polyethylene terephthalate, polyimide, and polyvinyl chloride into a plate shape, as described above. be able to. The RF tag 100 can be embedded in the card body 220 by injection molding or the like. The thickness of the card body 220 can be about 0.3 mm or more and 2.0 mm or less, and a preferable thickness is about 0.5 mm or more and 1.0 mm or less.

Note that the embedding position of the RF tag 100 is not limited. For example, as shown in FIG. 7, the RF tag 100 can be embedded in the center of the card body 220 in the thickness direction. In that case, the distance (thickness of the resin layer) t between the outer surface of the RF tag 100 and the outer surface of the card 210 can be set in the range of 0.05 mm or more and 0.3 mm or less, and more preferably 0.1 mm. The range is 0.2 mm or more.

In the embodiment shown in FIG. 6, the RF tag 100 is arranged in the lower corner of the insulating card body (hereinafter simply referred to as the card body) 220. The arrangement position of the RF tag 100 in the card body 220 is It may be at the corner of the card body 220, at the center, or at any position.

On the surface of the card 210, a display section 212 can be formed on which the card details printed by a thermal printer or the like can be printed. The card statement contains at least part of the data of card 210 . For example, there are the name of the orderer, the name of the contractor, the place of delivery, and the product number of the parts to be delivered. Note that the card 210 may record only the ID, and the above information may be recorded in the server.

Furthermore, a metal plate 250 may be attached to the back side of the card body 220 (the parts box side when the card is held by the holding portion). The metal plate 250 is formed in the same shape as the card body 220 . To attach the metal plate 250 to the back side of the card body 220, the metal plate 250 may be attached to the back side of the card body 220 using an adhesive, or the metal plate 250 may be attached to the back side of the card body 220 when the card body 220 is molded. may be integrally molded. Metal plates include steel plates, aluminum plates, copper plates, arbitrary conductors, and the like.

Further, metal plate 250 may be embedded in card body 220 instead of being attached to the back side of card body 220 . In this case, the metal plate 250 is embedded in the card body 220 on the part box 200 side of the RF tag 100 with the resin layers of the RF tag 100 and the card body 220 interposed therebetween. That is, the RF tag 100 and the metal plate 250 are electrically insulated by the resin layer.

The data of the parts management card 210 stored in the RF tag 100 can be read out without contact from a position several meters away, for example, by radio waves (e.g., UHF band radio waves) emitted from the antenna of the reader. can be done.
The configuration of the RF tag 100 embedded in the card body 220 will be described in detail below.

(RF tag 100)
Next, FIG. 8 is a schematic perspective view showing an example of the RF tag 100 on the front side, FIG. 9 is a schematic perspective view showing an example of the RF tag 100 on the back side, and FIG. 100 is a schematic expanded view showing an example. FIG.

As shown in FIGS. 8 to 10, the RF tag 100 includes at least an antenna 110 and an IC chip 80 that operates based on radio waves transmitted from a reader (not shown).

(antenna 110)
The antenna 110 includes a first waveguide element 20 , a second waveguide element 30 , an insulating base material 140 , a feed section 50 and a short circuit section 60 .

An insulator base (hereinafter referred to as an insulating base) 140 has an upper surface (first main surface) and a lower surface (second main surface) opposite to the first main surface. The insulating base material 140 is formed in, for example, a substantially rectangular parallelepiped shape, but is not limited to such a shape. For example, it may be disc-shaped, or it may have an arc-shaped cross section. Preferably, the insulating base material 140 has a shape corresponding to the surface shape of the parts management card body 220 at the position where the RF tag 100 is embedded.

As shown in FIG. 8, the first waveguide element 20 is provided on the top surface of the insulating base material 140 . As shown in FIG. 9, the second waveguide element 30 is provided on the bottom surface of the insulating base material 140 . Each of the first waveguide element 20 and the second waveguide element 30 has a rectangular shape and is formed by etching, pattern printing, or the like of a metal thin film such as aluminum.

A notch 25 is formed in a part of the short side of the first waveguide element 20 , and an IC chip 80 is arranged in the notch 25 . are connected so as to bridge between

The feeding section 50 is provided on the side surface and/or the top surface (or the bottom surface) of the insulating base material 140 and has one end electrically connected to the second waveguide element 30 . The short-circuit portion 60 is provided on the side surface of the insulating base material 140 , and has one end electrically connected to the first waveguide element 20 and the other end electrically connected to the second waveguide element 30 .
As shown in FIGS. 8 and 9, the feed portion 50 and the short-circuit portion 60 are arranged in parallel on the sheet 70 with a space therebetween so as to span the first waveguide element 20 and the second waveguide element 30. It is a member provided.

Note that the power supply portion 50 and the short-circuit portion 60 do not have to be provided in parallel with each other. Further, the feeding portion 50 and the short-circuit portion 60 may be integrally formed at the same time when the first waveguide element 20 and the second waveguide element 30 are formed. Alternatively, after forming the power feeding portion 50 and the short-circuiting portion 60 separately, the respective ends may be joined to the first waveguide element 20 and the second waveguide element 30 .

In this embodiment, as shown in FIGS. 8 to 10, the first waveguide element 20, the second waveguide element 30, the feeding portion 50 and the short-circuit portion 60 are formed on an insulating sheet 70. , is attached to the outer surface of the insulating base material 140 via the sheet 70 that is bent at the side portions of the insulating base material 140 .

That is, as shown in FIG. 10, a flexible sheet 70 having the first waveguide element 20, the second waveguide element 30, the power feed portion 50 and the short circuit portion 60 formed on one side thereof is placed between the power feed portion 50 and the short circuit portion. The antenna 110 can be easily manufactured by bending both at the portion 60 and attaching it to the front and rear surfaces of the insulating base material 140 .

As a material for forming the sheet 70, a flexible insulating material such as PET, polyimide, or polyvinyl chloride can be used. Although the thickness of the sheet 70 is not particularly limited, it is generally about several tens of micrometers. Moreover, the surface of each of the first waveguide element 20 and the second waveguide element 30 may be subjected to insulating coating treatment.

In this embodiment, the first waveguide element 20 and the second waveguide element 30 are thus formed on the sheet 70 (base material), but they do not necessarily have to be formed on the sheet 70. do not have. For example, the first waveguide element 20 and the second waveguide element 30 may be formed singly. Alternatively, the sheet 70 may be peeled off after the first waveguide element 20 and the second waveguide element 30 formed on the sheet 70 are transferred to the insulating substrate 140 .

A planar inverted F antenna is configured by the insulating base material 140, the first waveguide element 20, the second waveguide element 30, the feeding portion 50, and the short-circuit portion 60 described above.
This plate-shaped inverted F antenna receives radio waves transmitted from a reader (not shown). When the first waveguide element 20 absorbs radio waves, the second waveguide element 30 functions as a conductor base plate (also referred to as a ground portion). On the other hand, when the second waveguide element 30 absorbs radio waves, the first waveguide element 20 acts as a conductor ground plane. That is, the first waveguide element 20 and the second waveguide element 30 can function as both a waveguide element (antenna) and a conductor ground plane (ground) depending on the mode of use of the RF tag 100. .
Although the inverted F antenna is described in this embodiment, the present invention is not limited to this, and can be applied to any other antenna.

As shown in FIG. 8, the first waveguide element 20 has a total length A of sides 20a to 20f around it that is λ/4, λ/2, 3λ/4, or 5λ/8. is designed to Here, λ is the wavelength of radio waves transmitted from the reader. Note that the wavelength λ of the radio wave is not particularly limited as long as it is within the range in which the RF tag 100 can be used. As shown in FIG. 9, the second waveguide element 30 is designed such that the sum B of the lengths of the sides 30a to 30d around it is approximately equal to the sum A. As shown in FIG.

As described above, the sum of the lengths A and B of the sides around the first waveguide element 20 and the second waveguide element 30 is λ/4, λ/2, 3λ/4, or 5λ/8. approximately equal to This makes it possible to easily set the resonance frequency of the plate-shaped inverted-F antenna.

If the total lengths A and B of the sides around the first waveguide element 20 and the second waveguide element 30 are any of the above values, the first waveguide element 20 and the second waveguide element The planar shape of 30 is not limited to a rectangular shape. For example, the center portions of the first waveguide element 20 and the second waveguide element 30 may be cut off to form square shapes.

Alternatively, an insulator may be used as the insulating base material 140 . As a result, it is possible to secure an aperture area of a certain size and improve the sensitivity of the plate-shaped inverted F antenna. For example, it is possible to use Styrofoam as the insulating substrate 140 .

Also, the insulating substrate 140 may be a dielectric. As the insulating base material 140, for example, a dielectric having a dielectric constant of 1 or more and 20 or less can be used. When a dielectric with a large dielectric constant (for example, ceramic) is used, the capacitance of the capacitor is increased, so the opening areas of the first waveguide element 20 and the second waveguide element 30 are reduced, and the RF tag 100 can be made smaller. can be However, since the gain of the antenna 110 is reduced, the distance (communication distance) that can be communicated with the reader is shortened. If a relatively long communication distance of several meters or more is required, a dielectric with a low dielectric constant is used as the insulating base material 140 . In this case, the dielectric constant is preferably 5 or less. An embodiment using expanded polystyrene having a low dielectric constant will be described later.

The antenna 110 configured as described above constitutes a resonant circuit that resonates in the frequency band of radio waves transmitted from the reading device and received by the plate-shaped inverted F antenna. This resonance circuit is composed of an inductor pattern L and a capacitor (first capacitor) 93 (see FIG. 11).

Here, the inductor pattern L is composed of the first waveguide element 20, the short-circuit portion 60, the second waveguide element 30, and the feeding portion 50, and the capacitor 93 is composed of the first waveguide element 20, the second waveguide element 30 and an insulating base material 140 . This resonant circuit enables the plate-shaped inverted F antenna to receive radio waves (carrier waves) transmitted from the reader with high sensitivity, so that the reading performance of the RF tag 100 can be improved. Furthermore, the power supply voltage generated by the IC chip 80 can be increased.

(IC chip)
The IC chip 80 is provided between the first waveguide element 20 and the feeding section 50, as shown in FIG. The IC chip 80 is arranged on the upper surface side of the insulating base material 140 (on the same plane as the first waveguide element 20).
Note that the IC chip 80 may be arranged on the side surface of the insulating base 140 as long as it functions as a plate-shaped inverted F antenna. Alternatively, an external power supply may be connected to the IC chip 80 so that the IC chip 80 operates with the voltage supplied from the external power supply.

The IC chip 80 operates based on radio waves from the reading device received by the plate-shaped inverted F antenna of the antenna 110 .
Specifically, the IC chip 80 first rectifies a part of the carrier wave transmitted from the reader to generate the power supply voltage necessary for the IC chip itself to operate. Then, the IC chip 80 operates the logic circuit for control within the IC chip 80 with the generated power supply voltage. The IC chip 80 also operates a communication circuit or the like for transmitting and receiving data to and from the reading device. Furthermore, a non-volatile memory storing unique information of the parts box 200 can be operated.

Some IC chips 80 include a capacitor inside, and the IC chip 80 has stray capacitance. Therefore, it is preferable to consider the equivalent capacitance inside the IC chip 80 when setting the resonance frequency of the resonance circuit. In other words, the resonance circuit preferably has a resonance frequency set in consideration of the inductance of the inductor pattern L, the capacitance of the capacitor 93 and the equivalent capacitance inside the IC chip 80 . Additionally, the capacitance of the second capacitor is taken into account, as will be discussed below.

Thus, the RF tag 100 has the antenna 110 and the IC chip 80. FIG. The RF tag 100 receives radio waves (carrier waves) transmitted from the reader by the antenna 110 of the RF tag 100 . Then, identification data of the parts box 200 recorded in the IC chip 80 and the like are put on the reflected wave and sent back to the reader. This allows the RF tag 100 to communicate with the reader without bringing the reader into contact with the RF tag 100 .

(Equivalent circuit)
FIG. 11 is a diagram showing an example of an equivalent circuit of the parts management card 210 to which the metal plate 250 shown in FIGS. 6 and 7 is adhered. FIG. 12 is a diagram showing an example of an equivalent circuit in a state where the parts management card 210 is held by the holding portion 230 of the parts box 200. As shown in FIG.
As shown in FIG. 11, the equivalent circuit of the RF tag 100 consists of an inductor pattern L, a capacitor 93, and an IC chip 80. FIG. The inductor pattern L, the capacitor 93 and the IC chip 80 form a resonant circuit that resonates in the frequency band of radio waves transmitted from the reader.
The resonance frequency f [Hz] of this resonance circuit is given by equation (1). The value of the resonance frequency f is set so as to be included in the frequency band of radio waves transmitted from the reader.

In equation (1), La means the inductance of the inductor pattern L, Ca means the electrostatic capacity of the capacitor 93, and Cb means the equivalent capacity inside the IC chip 80.

Here, some IC chips 80 include a capacitor inside, and the IC chip 80 has stray capacitance. Therefore, when setting the resonance frequency f of the resonance circuit, it is preferable to consider the equivalent capacitance Cb inside the IC chip 80 .
That is, the resonance circuit preferably has a resonance frequency f set in consideration of the inductance of the inductor pattern L, the capacitance of the capacitor 93 and the equivalent capacitance Cb inside the IC chip 80 . As Cb, for example, a capacitance value published as one of specifications of the IC chip to be used can be used.

As described above, by considering the equivalent capacitance Cb inside the IC chip 80, the resonance frequency f of the resonance circuit can be accurately set to the frequency band of radio waves. As a result, the reading performance of the RF tag 100 can be further improved. Also, the power supply voltage generated by the IC chip 80 can be further increased.

Furthermore, in the card 210 to which the metal plate 250 is attached, between the waveguide plate (second waveguide element 30) of the RF tag 100 embedded in the card body 220 and the metal plate 250, A capacitor (second capacitor) 270 is formed by forming an electrical insulating layer made up of the main body 220 , and an inductance and resonance circuit of the RF tag 100 can be formed.

As shown in FIG. 11, the second capacitor 270 is connected in series with a capacitor 93 (first capacitor) composed of the first waveguide element 20, the second waveguide element 30, and the insulating substrate 140. As shown in FIG. Therefore, the combined capacitance of the first capacitor 93 and the second capacitor 270 may change, and the resonance frequency of the resonance circuit of the RF tag 100 may change significantly.

Specifically, when the capacity of capacitor 270 is much smaller than the capacity of capacitor 93 , the combined capacity is much lower than the capacity of capacitor 93 . This means that when the RF tag 100 is placed on the metal plate 250 with an insulating layer interposed therebetween, the resonance frequency of the resonance circuit of the RF tag 100 changes greatly, and the reading performance of the RF tag 100 deteriorates.

Therefore, in the present embodiment, the capacitance of capacitor 270 can be made equal to or greater than the equivalent capacitance inside IC chip 80 . As a result, the combined capacitance of the capacitor 93 and the capacitor 270 can be prevented from significantly decreasing, and performance degradation of the RF tag 100 can be suppressed. It is preferable that the capacity of the capacitor 270 is at least twice the equivalent capacity inside the IC chip 80 . More preferably, it is 2 times or more and 10 times or less.

Radio waves from the reader are received by one waveguide plate (first waveguide element) 20 of the RF tag 100 .
Then, through an IC chip circuit connected between the first waveguide element 20 of the RF tag 100 and the other second waveguide element (ground element) 30 of the RF tag 100, the second waveguide element 30 passes through the card. It is emitted to the metal plate 250 through the insulating layer of the main body 220 .
That is, since the RF tag 100 and the metal plate 250 are capacitively coupled via an insulating layer (dielectric), the metal plate 250 functions as an antenna.

Therefore, the metal plate 250 can act as an antenna. In this way, radio waves from the RF tag 100 can be sent to the reader through the metal plate 250, and radio waves from the reader can be received by the RF tag 100 through the metal plate 250. .
As a result, it is possible to reliably drive the RF tag 100 and read the RF tag 100 which is omnidirectional and has a long communication distance.

Furthermore, when the parts management card 210 is held in the holding part 230 of the metal parts box 200, as shown in FIG. ) and the component box 200, an electrical insulating layer made of the card body 220 is formed, and furthermore, an insulating layer made of a film or the like formed on the outer surface of the component box 200 separates the metal plate 250 from the metal plate 250. A capacitor (third capacitor) 272 is formed between the metal component box 200 and the inductance of the RF tag 100 to form a resonance circuit.

As shown in FIG. 12, third capacitor 272 is connected in series with first capacitor 93 and second capacitor 270 . Therefore, the combined capacitance of the first capacitor 93, the second capacitor 270, and the third capacitor 272 may change, and the resonance frequency of the resonance circuit of the RF tag 100 may change significantly.

Specifically, when the capacitance of third capacitor 272 is much smaller than the capacitances of second capacitor 270 and first capacitor 93, the combined capacitance is less than the capacitances of first capacitor 93 and second capacitor 270. decrease significantly. This means that when the RF tag 100 is placed in the parts box 200 with an insulating layer interposed therebetween, the coupling capacitance resonance frequency of the RF tag 100 greatly changes and the reading performance of the RF tag 100 deteriorates.

Therefore, in the embodiment shown in FIG. 12, the capacity of the third capacitor 272 can be made equal to or greater than the capacity of the second capacitor 270 and the equivalent capacity inside the IC chip 80 .
As a result, the combined capacitance of the first capacitor 93, the second capacitor 270 and the third capacitor 272 can be prevented from significantly decreasing, and performance degradation of the RF tag 100 can be suppressed. It is preferable that the capacity of the second capacitor 270 and the capacity of the third capacitor 272 be at least twice the equivalent capacity inside the IC chip 80 .

Radio waves from the reader are received by one waveguide plate (first waveguide element 20) of the RF tag 100, and are transmitted between the first waveguide element 20 of the RF tag 100 and the other second waveguide element of the RF tag 100. It passes through an IC chip circuit connected between wave elements (ground elements) and is emitted from the second waveguide element 20 to the metal parts box 200 through the insulating layer of the parts management card body 220 . That is, since the RF tag 100 and the parts box 200 are capacitively coupled via an insulating layer (dielectric), the parts box 200 functions as an antenna.

Therefore, the parts box 200 can act as an antenna. In this way, radio waves from the RF tag 100 can be sent to the reader via the parts box 200, and radio waves from the reader can be received by the RF tag 100 via the parts box 200. .
In this manner, the parts management apparatus of the present invention is configured such that the waveguide provided on the RF tag 100 and the parts box 200 are electrostatically coupled when the card 210 is held by the holding portion 230 .
As a result, it is possible to reliably drive the RF tag 100 and read the RF tag 100 which is omnidirectional and has a long communication distance.

(Second embodiment)
A second embodiment is shown in FIGS. In this embodiment, the configuration of the RF tag 100 is different from that of the first embodiment. FIG. 13 is a schematic perspective view showing an example of an RF tag 100 used in a parts management card 210 according to still another embodiment, and FIG. 14 is a schematic plan view of the RF tag 100 shown in FIG. 15 is a schematic plan view of the antenna section 300 of the RF tag 100 shown in FIG. 13. FIG.

The RF tag 100 of this embodiment is formed by attaching the circuit member 400 to the antenna section 300 via the insulating layer 420 . Since the insulating layer 420 is interposed between the antenna section 300 and the circuit member 400, a capacitor is formed therebetween.

(Antenna section 300)
The antenna section 300 is made of a metal plate and has a first area 310, a second area 320 and a third area 330 made of strip members. As the metal forming the metal plate, iron, copper, aluminum, silver, nickel, alloys thereof, or the like may be used. From the viewpoint of conductivity, workability and cost, the metal of the metal plate is preferably aluminum. The thickness of the metal plate is 0.3 mm or more and 1 mm or less from the viewpoint of strength.

(Circuit member 400)
16 is a schematic enlarged view of the circuit member 400 of the RF tag shown in FIG. 13. FIG.
As shown in FIG. 16, the circuit member 400 includes an IC chip 80 and a circuit 410 forming an inductor pattern L. As shown in FIG. The circuit 410 has a shape having a cutout portion obtained by cutting out a part of the ring-shaped circuit portion 411 . Specifically, it consists of the letter C of the alphabet. The circuit portion 411 has a side 411a, a side 411b, a side 411c, a side 411d and a side 411e. Note that the circuit 410 has been described as a case where a part of the circuit portion 411 is cut, but the present invention is not limited to this, and the cut portion may be replaced by an insulating portion.

In this embodiment, the circuit 410 consists of a thin film of aluminum. The thin film in this embodiment is formed with a thickness of 3 μm or more and 35 μm or less. The circuit 410 is formed by techniques such as etching or pattern printing.

An IC chip 80 is provided so as to bridge the notch of the circuit 410 of the circuit member 400 . In this embodiment, in the circuit member 400, the impedance of the inductor pattern L can be made constant by the internal area S of the circuit portion 411. FIG.

The IC chip 80 operates based on radio waves from the reader received by the antenna section 300 of the RF tag 100 .
Specifically, the IC chip 80 according to the present embodiment first rectifies part of the carrier wave transmitted from the reader to generate the power supply voltage necessary for the IC chip 80 itself to operate. Then, the IC chip 80 operates the logic circuit for control in the IC chip 80 and the non-volatile memory in which the unique information of the component box 200 and the like are stored by the generated power supply voltage.

The IC chip 80 also operates a communication circuit or the like for transmitting and receiving data to and from the reading device.

(insulating layer 420)
The insulating layer can have the same configuration as the insulating base material 140 shown in the first embodiment.

Moreover, in the present embodiment, it is desirable that the width T1 of the first region 310 of the antenna section 300 is formed to be 1 to 4 times the width T411 of the circuit section 411 of the circuit member 400 . It is preferable that the width T2 of the second region 320 of the antenna part 300 is formed to be 1 to 4 times the width T412 of the circuit part 411 of the circuit member 400 .

Moreover, it is desirable that the width T413 of the circuit portion 411 of the circuit member 400 is formed to be 1 to 4 times the width T412 of the circuit portion 411 of the circuit member 400 .
As a result, the circuit member 400 can be easily attached to the antenna section 300 .

FIG. 17 is a schematic perspective view of a parts management card 210 in which the RF tag 100 shown in FIG. 13 is embedded.
As shown in FIG. 17, a card 210 is configured by embedding the RF tag 100 having the above configuration in a card body 220 . Since the equivalent circuit of this card 210 is the same as that of FIG. 11, its explanation is omitted.

(Third Embodiment)
The third embodiment differs from the first and second embodiments in the shape of the feeding portion and the short-circuit portion of the antenna 110 of the RF tag.

18 is a schematic perspective view showing an example of the front side of the RF tag 100 of still another embodiment, and FIG. 19 is a schematic perspective view showing an example of the back side of the RF tag 100 shown in FIG. be. 20 is a schematic perspective view showing an example of the antenna 110 of the RF tag 100 shown in FIG. 18, and FIG. 21 is a schematic exploded view of the antenna 110 of the RF tag 100 shown in FIG.

As shown in FIGS. 18 to 21, the basic configuration of the antenna 110 of the third embodiment is similar to that of the first embodiment.
That is, the antenna 110 includes an insulating substrate 140 having a first main surface and a second main surface on the opposite side of the first main surface, a first waveguide element 20 provided on the first main surface, and a second main surface. A second waveguide element 30 provided on the main surface, a power feeding section 50 provided on a side surface on the long side of the insulating substrate 140 and having one end electrically connected to the first waveguide element 20, and an insulating substrate. a short-circuit portion 60 provided on the side surface of the short side of the material 140 and having one end electrically connected to the first waveguide element 20 and the other end electrically connected to the second waveguide element 30; ing.

The insulating substrate 140, the first waveguide element 20, the second waveguide element 30, the feeding portion 50, and the short-circuit portion 60 constitute a planar inverted F antenna 110 for receiving radio waves transmitted from the reader.
In addition, the inductor pattern composed of the first waveguide element 20, the short-circuit portion 60, the second waveguide element 30, and the feeding portion 50, the first waveguide element 20, the second waveguide element 30, and the insulating base material 140 A resonant circuit that resonates in the frequency band of radio waves is configured by the configured capacitor.

The first waveguide element 20 and the second waveguide element 30 are each formed in a rectangular shape having long sides and short sides.

The first waveguide element 20 and the second waveguide element 30 are connected by a short-circuit portion 60 on the short side of the first waveguide element 20 and the second waveguide element 30 .
A power feeding portion 50 is continuously provided at a location near the short side on the long side of the first waveguide element 20 . As shown in FIG. 21 , the feeding section 50 has a first feeding section 51 continuing from the body portion of the first waveguide element 20 and a second feeding section 52 continuing from the first feeding section 51 . The first feeding portion 51 is made of a relatively narrow conductor, and the second feeding portion 52 is made of a long rectangular conductor along the longitudinal direction of the first waveguide element 20 .
Furthermore, a rectangular notch 32 is formed on the short side of the first waveguide element 20 . The notch 32 forms a connecting portion 34 at the end of the first waveguide element 20 on the short side.

In the third embodiment, the power supply portion 50 is formed on a different surface from the short-circuit portion 60 . As a result, the area of the short circuit portion 60 can be increased. That is, the width LL of the short-circuit portion 60 shown in FIG. 18 can be increased. As a result, the resonance resistance becomes small, and the current flowing through the first waveguide element 20 and the second waveguide element 30 can be adjusted. As a result, it is possible to adjust the Q value determined from the frequency bandwidth.

As shown in FIG. 20, the first waveguide element 20 and the second waveguide element 30 are bent in two at the short-circuit portion 60, and the bent first waveguide element 20 and the second waveguide element 30 An insulating substrate 140 is placed therebetween. The first waveguide element 20 is attached to the first main surface of the insulating substrate 140 , and the second waveguide element 30 is attached to the second main surface of the insulating substrate 140 . As a result, the short-circuit portion 60 is arranged and adhered to the short-side side surface of the insulating base material 140 .

In addition, the power feeding portion 50 is bent from the side surface of the long side of the insulating base 140 so as to overlap the second waveguide element 30, and the power feeding portion 50 extends from the side surface of the long side of the insulating base 140 and the second waveguide. It is attached to the element 30 .
An IC chip 80 is arranged in the notch 32 formed in the first waveguide element 20, and the IC chip 80 is located between the connecting portion 34 of the first waveguide element 20 and the main body of the first waveguide element 20. It is connected so that it spans the

The insulating base material 140 can be formed from expanded polystyrene. In this embodiment, rectangular Styrofoam is used. Styrofoam having uniform closed cells inside can be used. The insulating base material 140 having such a structure has the same dielectric constant in its thickness direction.

Originally, it is most preferable to use air as the insulating base material 140. In order to prevent this, it is preferable to use styrene foam containing 90% by volume or more of air, more preferably closed-cell styrene foam containing 95% to 99% by volume of air.

By using expanded polystyrene, it is possible to maintain a predetermined spatial distance between the first waveguide element 20 (also referred to as the antenna section) and the second waveguide element 30 (also referred to as the ground section). Such an interval is preferably 0.5 mm or more and 3.0 mm or less.

It is desirable that the dielectric constant of the insulating base material 140 be in the range of 1% or more and 20% or less. It is more preferably 1.01% or more and 1.20% or less, most preferably 1.01% or more and 1.10% or less, and most preferably 1.02% or more and 1.08% or less.
When polystyrene foam is used as the insulating base material 140, the expansion ratio of the polystyrene foam is preferably 15 times or more and 60 times or less (in this case, the dielectric constant is 1.01% or more and 1.10% or less).

When ceramic (relative permittivity is more than 5% and 9% or less) is used as the insulating base material 140, the opening area of the antenna part and the ground part becomes small, and the communication distance is reduced. It can be made smaller.
On the other hand, when a material such as expanded polystyrene having a dielectric constant of 1% to 5% (especially 1.01% to 1.20%) is used as the insulating base material 140, the opening area of the antenna part and the ground part is can be kept large, and the communication distance can be extended from several meters to tens of meters.

The thickness of the insulating base material 140 made of polystyrene foam is preferably in the range of 0.5 mm or more and 3 mm or less.
In the present embodiment, the insulating base material 140 is made of polystyrene foam, but is not limited to this. Other foams or materials with

As described above, since the RF tag antenna 110 according to the present embodiment uses expanded polystyrene as the insulating base material 140 of the RF tag antenna 110, an opening area of a certain size can be secured. It is possible to improve the sensitivity of the plate-shaped antenna.
Furthermore, the insulating base material 140 may have a foam shape, may have one or a large number of cavities, or may be made of a composite material in which different types of materials are mixed or laminated.
When housing the RF tag 100 in a case, the inside of the case may be made of the same material as the insulating base material 140, in this embodiment, foamed polystyrene. That is, Styrofoam may be adhered to the surface of the RF tag 100 on which the IC chip 80 is mounted and to the first main surface, and the RF tag 100 may be accommodated in the case.

(Experimental result)
FIG. 22 is a schematic diagram showing the results of the reading experiment of the RF tag 100 described with reference to FIGS. 18 to 21. FIG.

Reference numeral 100M in FIG. 22 indicates the relationship between the theoretical reading distance (m) (vertical axis) and the frequency (horizontal axis) in a reading experiment using a reader from the surface side of the RF tag 100 according to the present embodiment. The curve 101M shown is a curve showing the relationship between the frequency and the theoretical reading distance (m) when a reading experiment was performed from the back side of the RF tag 100 according to the present embodiment using a reader.

Reference numeral 100N is a curve showing the relationship between the frequency and the theoretical reading distance (m) when a reading experiment was performed from the surface side of an inverted F antenna type RF tag (trade name 06) of the present applicant using a reader, and reference numeral 101N. is a curve showing the relationship between the frequency and the theoretical reading distance (m) when a reading experiment was performed from the back side of an RF tag (trade name 06) of the inverted F antenna type of the present applicant using a reader.

As shown in FIG. 22, the RF tag 100 according to the present embodiment can be read at a distance of 13 m when a reader is used from the surface side (solid line 100M).
On the other hand, when the reader is used from the back side of the RF tag 100 (solid line 101M), it can be read at a distance of 7 m.

As a result, in the case of the RF tag 100 of the inverted F antenna type of the present applicant, the RF tag 100 according to the present embodiment uses the reading device from the front side (broken line 100N) and the reading device from the back side. It was found that the performance was equal to or better than the case (dashed line 101N).

(Modification 1 of RF tag 100: Example using foamed polystyrene with different dielectric constants in the thickness direction as insulating base material 140)

As the insulating base material 140, expanded polystyrene having different dielectric constants in the thickness direction of the insulating base material 140 can also be used.

FIG. 23 is a schematic cross-sectional view of the RF tag 100. FIG.
The insulating base material 140 is composed of a laminate in which a plate-shaped polystyrene foam material 145 and a plate-shaped resin material 146 are laminated. The polystyrene foam material 145 is laminated on the antenna section 120 side, but the resin material 146 may be laminated on the antenna section 120 side.

Both the styrofoam material 145 and the resin material 146 are designed to have the same length. ABS can be used as the resin material, but it is not limited to this, and polyethylene, polypropylene, polyvinyl chloride, ceramics, paper, etc. may be used as the resin material.

Specifically, in the styrofoam material 145, if the dielectric constant εa of the styrofoam material 145 is 1.0 and the wavelength λ1 is calculated with a frequency of 900 MHz, then the antenna section 120 attached to the styrofoam material 145 is not affected by the dielectric constant. Therefore, the wavelength λ1 is λ1=(300/920 MHz)/1 ² ≈333 mm.

On the other hand, in the resin material 146, when the wavelength λ2 is calculated assuming that the resin material 146 has a dielectric constant εb of 5.0, a frequency of 900 MHz, and a propagation speed of 300 Mm/s, the wavelength λ2 of the resin material 146 is λ2=(300/ 920 MHz)/5 ² ≈149 mm.

Here, since the value λ1 of the antenna section 120 is 333 mm, it resonates at 402 MHz, which is 333/149≈2.23 times longer wavelength. In other words, it is the same as the ground portion 130 having an apparent length of 744 mm.
As a result, the same state as the RF tag 100 attached to the metal plate 250 can be achieved, and the RF tag 100 having a sufficient communication distance for metal or non-metal can be realized. The insulating base material 40 may be configured by laminating three or more layers of materials having different dielectric constants.

(Modified Example 2 of RF Tag 100: Example of Using Expanded Styrofoam with Dielectric Constant Different in Thickness Direction as Insulating Base Material 140)
FIG. 24 is a schematic cross-sectional view showing still another example of the RF tag 100. As shown in FIG.

Insulating substrate 140 has front surface 141 and back surface 142 . One or more holes 143 are formed that decrease in diameter from the surface 141 toward the back surface 142 . The hole 143 is not limited to one whose diameter is continuously reduced, and may be one whose diameter is reduced stepwise. According to such a configuration, the insulating base material 140 having different dielectric constants in the thickness direction of the insulating base material 140 can be obtained. In the embodiment shown in FIG. 24, the insulating base material 140 is obtained in which the relative dielectric constant is gradually lowered toward the antenna section 120 side.

In this embodiment, a stepped or conical hole 143 is described, but the shape of the hole is not limited to this. It may be a cylindrical, rectangular, or elliptical cylindrical hole that does not penetrate from the surface 141 to the back surface 142, or a conical cylinder that does not penetrate from the surface 141 to the back surface 142, or a pyramidal cylinder that does not penetrate. , or an elliptical cone-shaped hole.
Moreover, unlike the case where the hole 143 is shaped like a cylinder or a projection, a ring-shaped hole 143 forming a cylinder or a projection may be provided. That is, one or more cylinders or protrusions may be provided between the second main surface and the first main surface.
Furthermore, the cross-sectional shape of the hollow portion of the hole may change from the surface 141 toward the back surface 142 . For example, the hole may be star-shaped on the front surface 141 side, and the cross-sectional shape of the hole may be circular toward the rear surface 142 side.
Also, in FIG. 24, the case where the diameters of the holes 143 are the same has been described, but the present invention is not limited to this, and the diameters of the holes 143 may be the same or different.

As described above, by changing the dielectric constants on the front surface 141 side and the back surface 142 side, the ground portion 130 is apparently formed to be longer than a predetermined length. The RF tag 100 having enough can be realized.

(Still another example of RF tag 100)
FIG. 25 is a schematic diagram showing another example of the RF tag 100. As shown in FIG.
As shown in FIG. 25, the RF tag 100 consists of a plate antenna. The RF tag 100 is preferably made of a metal conductor with a thickness of 5 mm or less, and more preferably made of a metal conductor with a thickness of 2 mm or less. Alternatively, it may be formed by metal vapor deposition or the like.
As shown in FIG. 25, a long rectangular hole is formed along the short side at a location near the end of the short side of the rectangular antenna. Furthermore, a part of the belt-shaped portion on the short side of the antenna formed by the long hole is cut away to form a communicating portion through which the long hole communicates with the outside. An inductance L is formed by the elongated hole, and an IC chip 80 is mounted on the communicating portion of the belt-like portion.

Further, it is preferable that the total length of the antenna is 3/4λ of the center frequency from the central axis of the inductance L (broken line in the figure), which is the sum of length A + length B + length C + length D.

FIG. 26 is a schematic diagram showing an example of the relationship between the frequency band of the RF tag 100 of FIG. 25 and the communication distance.
As shown in FIG. 26, in the RF tag 100 of FIG. 25, when the center frequency is set to 894 MHz, the value of the inductance L is around 21 nH when the equivalent capacitance of the IC chip 80 is 1.5 pF.
Note that the equivalent capacitance of the IC chip 80 is not limited to 1.5 pF, and may be 0.2 pF or more and 5 pF or less. For example, it may be 0.6 pF.

As shown in FIG. 26, when the center frequency is 894 MHz, a communication distance of about 7 m can be obtained even at 860 MHz in Europe, and a communication distance of about 8 m can be obtained at 930 MHz in Japan and the United States. all right.

27 is a schematic diagram showing another example of the RF tag 100 of FIG. 25. FIG.
The RF tag 100 shown in FIG. 27 may form the RF tag 100 shown in FIG. 25 by attaching a partial RF tag portion 100a including the inductance L and the IC chip 80 to a plate antenna.
That is, the RF tag 100 shown in FIG. 25 may be formed by connecting a plurality of members instead of being formed by a sheet of metal conductor.
That is, the total length of the antenna is set to be an integral multiple of the frequency. For example, it is set to be less than 1λ or greater than 1λ. This is because power cannot be supplied in the case of exactly 1λ, 2λ, and nλ (n is an integer).

28 and 29 are schematic diagrams showing an example of the structure of the card 210. FIG.
As shown in FIG. 28, the card 210 has a structure in which a rewrite sheet 201 is attached to one side of the RF tag 100 shown in FIGS. May be.
This forms a card 210 that can be used in the parts box 200 described in FIGS. 1-5.

In addition, as shown in FIG. 29, it is preferable that at least a part of the RF tag 100, the RF tag portion 100a (see FIG. 27), is wrapped with a non-conductor 205. As shown in FIG. As a result, frequency characteristics of inductance L and IC chip 80 can be stabilized.

As described above, the metal plate 250 and/or the parts box 200 can be used as an antenna, and a large opening area can be provided, so that the sensitivity of the RF tag 100 can be improved.

In addition, since the metal plate 250 and/or the parts box 200 can be used as an antenna, omnidirectional reading by the reader is possible.

In the present invention, the parts box 200 corresponds to the "parts box", the holding section 230 corresponds to the "holding section", the parts management card 210, the card 210 corresponds to the "parts management card", and the parts management The card body 220, the card body 220 corresponds to the "parts management card body", the metal plate 250 corresponds to the "metal plate", the RF tag 100 corresponds to the "RF tag", and the antenna 110 corresponds to the "antenna". , the IC chip 80 corresponds to the "IC chip", and the waveguide element, the first waveguide element 20, and the antenna section 300 correspond to the "waveguide plate".

Although one preferred embodiment of the invention is described above, the invention is not so limited. It is understood that various other embodiments can be made without departing from the spirit and scope of the invention. Furthermore, in this embodiment, the actions and effects of the configuration of the present invention are described, but these actions and effects are examples and do not limit the present invention.

20 First waveguide element 30 Second waveguide element 50 Feeding part 60 Short circuit part 80 IC chip 93 Capacitor 100 RF tag 110 Antenna 200 Parts box 210 Parts management card 220 Parts management card body 230 Holding part 250 Metal plate 300 Antenna Department

Claims (9)

A parts management card detachably held in a holding part attached to the outer surface of a parts box containing parts,
An insulator-made parts management card body,
an RF tag embedded in the parts management card body;
Disposed on the part box side of the RF tag, in the parts management card main body or on the outer surface of the parts management card main body with the insulating layer of the parts management card main body interposed between the RF tag and the RF tag. a metal plate mounted thereon;
The RF tag includes at least an antenna and an IC chip that operates based on radio waves transmitted from a reader,
The waveguide plate provided in the RF tag and the metal plate are electrically connected via a constant capacitance ,
The waveguide plate is a waveguide element provided in the antenna,
The antenna comprises an insulating base material having a first main surface and a second main surface opposite the first main surface;
a first waveguide element provided on the first main surface;
a second waveguide element provided on the second main surface;
a feeding section provided on the first side surface of the insulating base material and having one end electrically connected to the second waveguide element;
provided on a second side surface adjacent to the first side surface of the insulating base, one end of which is electrically connected to the first waveguide element and the other end of which is electrically connected to the second waveguide element and
The insulating base, the first waveguide element, the second waveguide element, the feeding portion, and the short-circuiting portion constitute a plate-shaped antenna for receiving the radio wave transmitted from the reading device,
An inductor pattern composed of the first waveguide element, the short-circuit portion, the second waveguide element, and the feeding portion, and an inductor pattern composed of the first waveguide element, the second waveguide element, and the insulating base material A parts management card, in which a resonance circuit that resonates in the frequency band of the radio wave is formed by a capacitor and a capacitor . A parts management card detachably held in a holding part attached to the outer surface of a metal parts box containing parts,
An insulator-made parts management card body,
an RF tag embedded in the parts management card body;
The RF tag includes at least an antenna and an IC chip that operates based on radio waves transmitted from a reader,
held by the holding unit so that the waveguide plate provided in the RF tag and the component box are electrostatically coupled ,
The waveguide plate is a waveguide element provided in the antenna,
The antenna comprises an insulating base material having a first main surface and a second main surface opposite the first main surface;
a first waveguide element provided on the first main surface;
a second waveguide element provided on the second main surface;
a feeding section provided on the first side surface of the insulating base material and having one end electrically connected to the second waveguide element;
provided on a second side surface adjacent to the first side surface of the insulating base, one end of which is electrically connected to the first waveguide element and the other end of which is electrically connected to the second waveguide element and
The insulating base, the first waveguide element, the second waveguide element, the feeding portion, and the short-circuiting portion constitute a plate-shaped antenna for receiving the radio wave transmitted from the reading device,
An inductor pattern composed of the first waveguide element, the short-circuit portion, the second waveguide element, and the feeding portion, and an inductor pattern composed of the first waveguide element, the second waveguide element, and the insulating base material A parts management card, in which a resonance circuit that resonates in the frequency band of the radio wave is formed by a capacitor and a capacitor . A parts management card detachably held in a holding part attached to the outer surface of a parts box containing parts,
An insulator-made parts management card body,
an RF tag embedded in the parts management card body;
Disposed on the parts box side of the RF tag, in the parts management card main body or on the outer surface of the parts management card main body with the insulating layer of the parts management card main body interposed between the RF tag and the RF tag. a metal plate mounted thereon;
The RF tag includes at least an antenna and an IC chip that operates based on radio waves transmitted from a reader,
The waveguide plate provided in the RF tag and the metal plate are electrically connected via a constant capacitance,
The waveguide plate is the antenna,
The antenna is a plate-like antenna having a substantially rectangular shape, and a long rectangular hole is formed along the short side near the end of the short side, and the long hole is formed by the long hole. A part of the belt-shaped portion on the short side is cut away to form a communicating portion in which the long hole communicates with the outside to form an inductor pattern, and the IC chip is mounted in the communicating portion,
The total length of the antenna is set to be an integral multiple of the wavelength λ of the radio wave of the frequency of the RF tag,
A parts management card, wherein the inductor pattern and the internal capacitance of the IC chip form a resonance circuit that resonates in the frequency band of the radio wave. A parts management card detachably held in a holding part attached to the outer surface of a metal parts box containing parts,
An insulator-made parts management card body,
an RF tag embedded in the parts management card body;
The RF tag includes at least an antenna and an IC chip that operates based on radio waves transmitted from a reader,
held by the holding unit so that the waveguide plate provided in the RF tag and the component box are electrostatically coupled,
The waveguide plate is the antenna,
The antenna is a plate-like antenna having a substantially rectangular shape, and a long rectangular hole is formed along the short side near the end of the short side, and the long hole is formed by the long hole. A part of the belt-shaped portion on the short side is cut away to form a communicating portion in which the long hole communicates with the outside to form an inductor pattern, and the IC chip is mounted in the communicating portion,
The total length of the antenna is set to be an integer multiple of the wavelength λ of the radio wave of the frequency of the RF tag,
A parts management card, wherein the inductor pattern and the internal capacitance of the IC chip form a resonance circuit that resonates in the frequency band of the radio wave. The parts box is made of metal,
4. The parts management card according to claim 1 , held by said holder so that said waveguide plate provided on said RF tag and said parts box are electrostatically coupled. The outer peripheral distance of at least one of the first waveguide element and the second waveguide element is λ/4, λ/2, or 3λ with respect to the wavelength λ of the radio wave at the frequency of the RF tag. 3. The parts management card according to claim 1 , which is designed to satisfy any one of /4 and 5[lambda]/8. 5. The parts management card according to claim 3 , wherein at least said IC chip and said inductor pattern are wrapped with a non-conductive material. 8. The parts management card according to claim 1 , wherein said parts management card is a kanban used in a parts management system. A parts management device comprising : the metal parts box in which parts are stored; and the parts management card according to any one of claims 1 to 8 ,
A parts management apparatus, wherein the waveguide provided on the RF tag and the parts box are electrostatically coupled when the parts management card is held by the holding unit.

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