JP6647646B1 - Electronic tag reader - Google Patents

Abstract

An electronic tag in a storage box is simultaneously and simultaneously read with a simple configuration, and erroneous reading of another electronic tag near the apparatus is prevented. In the electronic tag reading device, a tunnel section 11 has a part of a passing section 10 as a lower surface, and a storage box B passes inside. The antennas 12 are provided on the left side surface 11a, the right side surface 11b, and the upper surface 11c of the inner surface of the tunnel portion 11 with respect to the direction in which the storage box B passes. It is installed so that it faces. The shield plate 13 is made of a radio-absorbing plate, has a hole 13 a having a predetermined diameter in the center of the plate, and is installed so that the hole 13 a is located in front of the transmitting surface of the antenna 12. The curtain 14 is formed of a radio-absorptive shield cloth, and is provided on each of the front surface 11d and the back surface 11e of the tunnel portion 11 with respect to the passing direction of the storage box B. It is possible to enter and exit. [Selection diagram] Fig. 1

Description

  The present invention relates to an electronic tag reader.

  2. Description of the Related Art Conventionally, electronic tags attached to a plurality of articles (uniforms, clothes, clothes, accessories, books, etc.) stored in storage boxes such as cardboard boxes and containers are simultaneously read at the same time, and article storage management and inventory management. There are electronic tag readers that perform such operations efficiently.

  For example, Japanese Patent Laying-Open No. 2008-140216 (Patent Literature 1) discloses an IC tag reading device that reads RFID tags at a time. In this IC tag reader, an RFID antenna for reading information stored in the RFID tag is arranged on one side of a passage through which an object to which the RFID tag is attached passes, and radio waves radiated from the RFID antenna are provided. A vertical radio wave absorption front wall and a radio wave absorption rear wall for narrowing the half-value angle in a plan view are provided so as to protrude from the vicinity of the front edge and the rear edge of the RFID antenna toward the passage portion, and the other side across the passage portion The radio wave absorption side wall is arranged. With this configuration, it is possible to control the radiated radio wave (zone control) with a simple configuration, prevent reading of tag information at an undesired place, and prevent interference with radio waves radiated from another antenna adjacent to the device. It is possible. As a result, in the physical distribution in the FRID system having a large communication area, it is possible to surely manage an article (identified body) desired to be identified accurately.

  Japanese Patent Application Laid-Open No. 2009-80588 (Patent Document 2) discloses a method of collectively reading information of IC tags attached to a plurality of articles. In this method, an electromagnetic induction method is used for reading an IC tag, and information on the IC tag is read by moving a plurality of articles relative to at least one or more reader / writer antennas and collectively. . An IC tag reader corresponding to the method is also disclosed, and the IC tag reader includes a reader / writer antenna and a moving unit that relatively moves a plurality of articles with respect to the reader / writer antenna. As a result, the possibility that the magnetic flux generated from the reader / writer antenna passes through the antenna loops of all the IC tags increases, so that the probability of reading the IC tags can be significantly increased.

  Further, Japanese Patent Application Laid-Open No. 2011-8708 (Patent Document 3) discloses an IC tag reader including a turntable, an antenna, an anechoic box, a reader, and a control computer. The turntable mounts a storage box containing a plurality of electronic tags storing information and rotates the storage box. The antenna wirelessly communicates with the electronic tag using radio waves of a predetermined frequency. The anechoic box blocks radio waves of a predetermined frequency and has a turntable and an antenna installed inside. The reader reads information stored in the electronic tag via the antenna. The control computer causes the reader to read information stored in the electronic tag while rotating the turntable. This makes it possible to collectively read electronic tags attached to a plurality of documents in a document storage box, and to grasp the contents and quantity of documents in a short time without labor.

JP 2008-140216 A JP 2009-80588 A JP 2011-8708 A

  The electronic tag reader is usually of a tunnel type, and a shutter for blocking radio waves (electromagnetic waves) is provided at the entrance and the exit of the tunnel, and when the storage box enters the inside of the electronic tag reader. Then, the shutter at the entrance is closed so that only the electronic tag of the article in the storage box is reliably read. Also, as another configuration of the electronic tag reading device, without providing a shutter at the entrance and exit, the directivity of the antenna for reading the electronic tag is devised to reduce the possibility of radio wave leakage of the antenna from the entrance and exit of the tunnel. This prevents erroneous reading of tags.

  However, an electronic tag reader provided with a shutter at the entrance and exit requires an opening / closing mechanism that automatically opens and closes the shutter at the entrance and exit while the storage box is transported by the electric conveyor, and there is a problem that the apparatus becomes large and costs increase. . In addition, the electric conveyor and the opening / closing mechanism require maintenance and have a problem that it is difficult to introduce them into existing devices.

  Further, in the electronic tag reader in which the directional characteristics of the antenna are adjusted, it is necessary to prepare a special antenna, and it is necessary to control the radio wave reach with high accuracy, and there is a problem that such adjustment is difficult. In addition, there is a problem that a cost is required for a special antenna.

  In the technology described in Patent Literature 1, it is necessary to prepare three radio wave absorption walls for the RFID antenna: a radio wave absorption front wall, a radio wave absorption rear wall, and a radio wave absorption side wall. There is a problem that the device is bulky and the device becomes large. Further, in the technique described in Patent Document 2, there is no description about a method for preventing erroneous reading of another electronic tag existing near the outside of the apparatus. Furthermore, the technique described in Patent Document 3 needs to be configured as an anechoic box as a whole, and has a problem that it is difficult to introduce it into an existing device.

  Therefore, the present invention has been made to solve the above problem, and despite having a simple configuration, it is possible to simultaneously read a plurality of electronic tags in a storage box at the same time, An object of the present invention is to provide an electronic tag reading device capable of preventing erroneous reading of another electronic tag existing in the vicinity.

  An electronic tag reading device according to the present invention includes a passing unit, a tunnel unit, an antenna, a shield plate, a curtain, and a control unit. The passing unit passes a storage box that stores an article with an electronic tag. The tunnel portion has a part of the passing portion as a lower surface, and the storage box passes through the inside. The antenna is provided on each of the left side surface, the right side surface, and the upper surface with respect to the passing direction of the storage box, of the inner surface of the tunnel portion, such that a transmitting surface for transmitting radio waves faces the inside of the tunnel portion. Will be installed. The shield plate is made of a radio wave absorbing plate, has a hole of a predetermined diameter at the center of the plate, and is installed so that the hole is located in front of the transmitting surface of the antenna. The curtain is formed of a radio-absorptive shield cloth, and is provided on each of the front and back sides of the tunnel portion with respect to the passing direction of the storage box, so that the storage box can enter and exit the tunnel portion. Make it possible. The control unit transmits radio waves from the transmitting surface of the antenna to the storage box entering the inside of the tunnel unit, and reads information of the electronic tag of the article in the storage box.

  According to the present invention, it is possible to simultaneously read a plurality of electronic tags in a storage box at the same time in spite of a simple configuration, and prevent erroneous reading of other electronic tags existing near the outside of the apparatus. It is possible to do.

It is a key map of an electronic tag reader concerning an embodiment of the present invention. It is a front sectional view with respect to the passing direction of the storage box in the electronic tag reader according to the embodiment of the present invention. FIG. 2 is a perspective view of an antenna and a shield plate of the electronic tag reader according to the embodiment of the present invention. It is the front view with respect to the passing direction of the storage box in the electronic tag reader which concerns on an Example, and the perspective view inside an apparatus. 4 is a table illustrating a relationship between a diameter of a hole in a shield plate and a radio wave reach distance of an antenna when a control unit reads information of an electronic tag via an antenna in an example. A left side view and a front view (FIG. 6A) of the electronic tag reader according to the embodiment with respect to the passing direction of the storage box, and a left side view and a front view of the electronic tag reader before the storage box is carried in with respect to the passing direction of the storage box. (FIG. 6B). A left side view in the passing direction of the storage box in the electronic tag reading device when the storage box is carried in and a display example of the control unit (FIG. 7A), and a left side in the electronic tag reading device after the storage box is carried out in the reading direction of the storage box. FIG. 7B is a front view and a front view (FIG. 7B).

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention.

  As shown in FIG. 1 to FIG. 3, the electronic tag reader 1 according to the present invention includes a passing unit 10, a tunnel unit 11, an antenna 12, a shield plate 13, a curtain 14, and a control unit 15. Prepare.

  The passing unit 10 allows the storage box B that stores the article O with the electronic tag T to pass therethrough. The tunnel part 11 has a part of the passing part 10 as a lower surface, and the storage box B passes through the inside. The antennas 12 are provided on the left side surface 11a, the right side surface 11b, and the upper surface 11c of the inner surface of the tunnel portion 11 with respect to the passing direction of the storage box B, respectively. It is installed to face the inside.

  The shield plate 13 is made of a radio wave absorbing plate, has a hole 13 a having a predetermined diameter in the center of the plate, and is installed so that the hole 13 a is located in front of the transmitting surface 12 a of the antenna 12. The curtain 14 is formed of a shield cloth that absorbs radio waves, and is provided on each of the front surface 11d and the rear surface 11e of the tunnel portion 11 with respect to the passing direction of the storage box B. To enter and exit.

  The control unit 15 transmits radio waves from the transmitting surface 12a of the antenna 12 to the storage box B that has entered the inside of the tunnel unit 11, and reads information of the electronic tag T of the article O in the storage box B.

  This makes it possible to simultaneously read a plurality of electronic tags in the storage box B at the same time in spite of the simple configuration, and to prevent erroneous reading of other electronic tags existing near the outside of the apparatus. Becomes possible.

  That is, according to the present invention, since the shield plate 13 having the hole 13a is provided in front of the transmission surface 12a of the antenna 12, the shield plate 13 is extremely simple. Further, since the shield plate 13 is not bulky, the size of the device can be reduced.

  In addition, the shield plate 13 limits the radio wave reach of the transmitting surface 12a of the antenna 12 to the inside of the tunnel unit 11, so that even if a plurality of electronic tags T exist inside the tunnel unit 11, the electronic tags T are collectively and simultaneously. It becomes possible to read the information of the tag T, prevent the leakage of the radio wave of the transmitting surface 12a to the outside of the device, and prevent the electronic tag T existing near the outside of the device from being erroneously read.

  In the present invention, since the antennas 12 are provided on the left side surface 11a, the right side surface 11b, and the upper surface 11c of the inner surface of the tunnel portion 11, radio waves are transmitted to the inner surface of the tunnel portion 11 from three directions. Then, the information of the electronic tag T is read. As described above, by providing the antennas 12 in three directions with respect to the passing direction of the storage box B, the direction of the radio wave receiving antenna of the electronic tag T of the article O in the storage box B is determined. Since the transmitting surfaces 12a of the antennas 12 in three directions can transmit radio waves evenly to the storage box B, the antenna for receiving radio waves of the electronic tag T can It is possible to reliably receive any of the radio waves on the transmitting surfaces 12a of the three antennas 12). Therefore, the information of the electronic tag T of the article O in the storage box B can be read without leaking.

  In the present invention, the curtain 14 is provided at each of the front surface 11d (entrance) and the back surface 11e (exit) serving as the entrance and exit of the tunnel portion 11, so that the entrance and exit of the tunnel portion 11 where radio wave leakage is likely to occur is blocked by the curtain 14. However, it is possible to achieve both batch reading of a plurality of electronic tags T and prevention of radio wave leakage.

  Here, although there is no particular limitation on the configuration of the passage unit 10, for example, as shown in FIG. 1, a roller conveyor provided with a plurality of rollers 10a may be used, or a belt conveyor may be used. By moving the storage box B, the storage box B may be passed through the passage unit 10.

  Further, the type of the electronic tag T is not particularly limited, and examples thereof include an RF (radio frequency) tag in a UHF (Ultra High Frequency) band (for example, 860 MHz to 960 MHz, a 2.45 GHz band, and the like). The RF tag is an IC (integrated circuits) tag that operates by receiving a radio wave from the transmitting surface 12a of the reader / writer antenna 12.

  Further, the type of the article O is not particularly limited. For example, as shown in FIG. 1, a uniform having an electronic tag T as an emblem can be given. In addition, the article O may include clothes, clothes, accessories, books, and the like. The type of the storage box B is not particularly limited, and examples thereof include cardboard and containers.

  Further, although there is no particular limitation on the configuration of the tunnel portion 11, for example, as shown in FIG. 1, respective ends of a plate-shaped left side surface 11a, an upper surface 11c, and a right side surface 11b are connected in this order, The sectional view may be a U-shape, or the ends of the curved left side surface 11a, upper surface 11c, and right side surface 11b may be connected in this order, and the sectional view may be a U-shape. It does not matter.

  The configuration of the antenna 12 is not particularly limited. For example, a radio wave can be transmitted to the radio wave receiving antenna of the electronic tag T without being affected by the direction of the radio wave receiving antenna of the electronic tag T. It is preferable to employ the circularly polarized antenna 12. Further, it is not necessary to use a special antenna as the antenna 12, and an example of the antenna 12 is a plate-shaped antenna 12 as shown in FIG.

  Although there is no particular limitation on the installation position of the antenna 12, for example, as shown in FIGS. 1 and 2, the three antennas 12 installed on the left side surface 11a, the right side surface 11b, and the upper surface 11c May be installed in a straight line in the inner circumferential direction of the tunnel portion 11 with respect to the passing direction of the tunnel. Further, any or all of the three antennas 12 installed on the left side surface 11a, the right side surface 11b, and the upper surface 11c may be installed at the center of the inner surface of the tunnel portion 11, or the front surface of the inner surface of the tunnel portion 11 may be installed. It may be installed on the 11d side or the back surface 11e side.

  The configuration of the shield plate 13 is not particularly limited, but the simplest configuration is a configuration in which one hole 13a is provided in the center of the shield plate 13 as shown in FIG. Since the hole 13a is located in front of the transmitting surface 12a of the antenna 12 and faces the transmitting surface 12a, the hole 13a functions as a radio wave transmission window, and can limit the radio wave reach of the antenna 12.

  The shape of the hole 13a of the shield plate 13 is not particularly limited, but the simplest configuration may be a circular shape as shown in FIG. The material of the shield plate 13 is not particularly limited, and a known radio wave absorbing material can be used.

  In addition, the shield plate 13 is provided so that the hole 13a of the shield plate 13 contacts the transmitting surface 12a of the antenna 12 as shown in FIGS. Preferably, one surface of the shield plate 13 is placed so as to overlap the transmitting surface 12a of the antenna 12.

  Here, a proportional relationship is established between the diameter of the hole 13a of the shield plate 13 and the radio wave reach distance. Therefore, the diameter of the hole 13 a of the shield plate 13 is appropriately designed so that the radio wave reach distance corresponds to the size inside the tunnel portion 11.

  For example, the diameter of the hole 13 a of the shield plate 13 installed in front of the antenna 12 on the left side surface 11 a (or the right side surface 11 b) of the tunnel portion 11 is such that the radio wave reach distance of the antenna 12 is rightward from the left side surface 11 a of the tunnel portion 11. It is designed to correspond to the size (distance) up to the surface 11b. The diameter of the hole 13a of the shield plate 13 installed in front of the antenna 12 on the upper surface 11c of the tunnel portion 11 is such that the radio wave reach distance of the antenna 12 from the upper surface 11c of the tunnel portion 11 to the passing portion 10 (the lower surface of the tunnel portion 11). It is designed to correspond to the size (distance) up to).

  Here, the radio wave leakage of the antenna 12 installed on the upper surface 11c of the tunnel portion 11 is more remarkable than the radio wave leakage of the antenna 12 installed on each of the left side surface 11a and the right side surface 11b of the tunnel portion 11. Therefore, for example, the diameter of the hole 13a of the shield plate 13 in the antenna 12 on the upper surface 11c of the inner surface of the tunnel portion 11 is equal to the diameter of the hole 13a of the shield plate 13 in the antenna 12 on the left surface 11a and the right side 11b of the inner surface of the tunnel portion 11, respectively. Is preferably smaller than the diameter of Thereby, the radio wave reaching distance of the antenna 12 on the upper surface 11c of the tunnel portion 11, in which the influence of the radio wave leakage appears remarkably, is shorter than the radio wave reaching distance of each of the antennas 12 on the left side surface 11a and the right side surface 11b. The influence of radio wave leakage from the antenna 12 on the upper surface 11c of the antenna 11 can be reduced, and radio wave leakage can be reliably prevented.

  Further, regarding the diameter of the hole 13a of the shield plate 13, specifically, when the electronic tag T is an RF tag in the UHF band, the diameter of the hole 13a of the shield plate 13 is larger than 160 mm and smaller than 200 mm. It is preferable that it is within the range. In this case, for example, the vertical size and the horizontal size in front view with respect to the passing direction of the storage box B in the tunnel portion 11 are in the range of 400 mm to 600 mm, and the vertical size or the horizontal size of the storage box is in the range of 400 mm to 600 mm. It is preferable to be within.

  Although the size of the shield plate 13 is not particularly limited, in order to limit the radio wave reach of the antenna 12 with high accuracy, for example, the plane size of the shield plate 13 facing the transmitting surface 12a of the antenna 12 is It is preferable that the transmission surface 12a be configured to have a plane size equal to or larger than the plane size.

  Although there is no particular limitation on the structure of the curtain 14, from the viewpoint of preventing radio wave leakage and easy access of the storage box, for example, as shown in FIG. It is also possible to use a shield cloth having a radio-absorptive property, or to overlap two radio-absorptive shield cloths in order to prevent radio wave leakage. When the curtain 14 is formed by stacking two radio-absorptive shield cloths, for example, the thickness of one shield cloth may be equal to or different from the thickness of the other shield cloth. As the thickness of the curtain 14 increases, the toughness of the curtain 14 increases and the entrance and exit of the storage box B become difficult. Therefore, the thickness of the curtain 14 is appropriately designed according to the size, strength, passing speed, and the like of the storage box B. For example, when the curtain 14 is configured by stacking two radio-absorptive shield cloths, the toughness of one shield cloth is increased by increasing the thickness of one shield cloth compared to the thickness of the other shield cloth. The storage box B may be easily moved in and out according to the toughness of the curtain 14. Further, the material of the curtain 14 is appropriately designed according to the size of the tunnel portion 11, the radio wave reach of the antenna 12, and the like.

  The configuration of the control unit 15 is not particularly limited. For example, there are two elements: a reader / writer that converts an electric signal from the antenna 12 into information, and a computer (terminal device) that stores the information converted by the reader / writer. It consists of. The control unit 15 is electrically connected to the antenna 12 and transmits an electric signal to the antenna 12 and receives an electric signal from the antenna 12 as information, as shown in FIGS.

  Specifically, the antenna 12 emits the electric signal transmitted from the control unit 15 into the air as a radio wave, and receives the radio wave emitted from the electronic tag T and converts it into an electric signal. The reader / writer of the control unit 15 converts an electric signal of the antenna 12 into information, converts information from a computer into an electric signal, and sends the electric signal to the antenna 12. The computer of the control unit 15 controls the operation of the reader / writer, and issues commands for starting and stopping the operation of the reader / writer, reading information of the electronic tag T, writing information to the electronic tag T, and the like. In the above description, the control unit 15 is configured by a reader / writer and a computer. However, for example, when the antenna 12 is integrated with the reader / writer, the control unit 15 may be simply configured by a computer. .

  The type of information of the electronic tag T read by the control unit 15 is not particularly limited, and examples include identification information of the article O such as product information indicating the product of the article O and type information indicating the type of the article O. I can do it.

  Further, there is no particular limitation on the method by which the control unit 15 reads the information of the electronic tag T. For example, when the passing unit 10 is a roller conveyor, the control unit 15 rotates the roller conveyor of the passing unit 10 forward, so that the storage box B placed on the passing unit 10 passes through the passing unit 10 of the roller conveyor. Then, when entering the inside of the tunnel unit 11 from the curtain 14 on the front surface 11d (entrance) of the tunnel unit 11, the control unit 15 sends electric signals to the three antennas 12 and causes the antennas 12 to transmit radio waves.

  Here, the order of transmitting the radio waves from the three antennas 12 of the control unit 15 is not particularly limited. For example, the control unit 15 may transmit the antennas 12 of the top surface 11c, the left side surface 11a, and the right side surface 11b of the tunnel unit 11 respectively. May be transmitted sequentially, or the electric signals may be transmitted to all the antennas 12 simultaneously.

  When the electronic tag T of the article O in the storage box B receives a radio wave, the radio wave including information stored in advance in the storage unit of the electronic tag T is transmitted. Here, when a plurality of electronic tags T are present in the storage box B, each of the electronic tags T transmits a radio wave.

  Here, since three antennas 12 are provided inside the tunnel portion 11 so as to surround the outer periphery of the storage box B, even if each of the plurality of electronic tags T transmits a radio wave in any direction, One of the three antennas 12 receives the radio wave of the electronic tag T.

  When the antenna 12 receives the radio wave of the electronic tag T, the antenna 12 converts the radio wave into an electric signal and transmits the electric signal to the control unit 15. The control unit 15 acquires the information of the radio wave based on the electric signal, and The information of the electronic tag T is registered by storing the information in the storage unit 15. Thereby, a plurality of electronic tags T can be read in the storage box B at once.

  Then, as the control unit 15 continues the circling of the roller conveyor, the storage box B passes through the inside of the tunnel unit 11 and is carried out of the curtain 14 on the back surface 11e (exit) of the tunnel unit 11 to the outside. This completes the batch reading of the electronic tag T of the article O in the storage section B.

  Here, in the present invention, the radio wave reach of the antenna 12 is limited to the inside of the tunnel section 11 to prevent the occurrence of radio wave leakage. Therefore, even if another electronic tag T exists near the outside of the device, In addition, only the electronic tag T of the target storage box B can be read at a time without erroneous reading of another electronic tag T.

  In the present invention, if the number of electronic tags T of the articles O in the storage box B is large and the information of the electronic tags T cannot be read, the control unit 15 rotates the roller conveyor of the passing unit 10 in the reverse direction. Then, the storage box B may run backward through the passage section 10 of the roller conveyor, and then re-enter the storage box B from the curtain 14 on the back surface 11e of the tunnel section 11 to the inside of the tunnel section 11. Then, the control unit 15 transmits a radio wave from each antenna 12, receives a radio wave of the electronic tag T using each antenna 12, and acquires information on the radio wave. Then, the storage box B passes through the inside of the tunnel portion 11 and is carried out from the curtain 14 on the front surface 11d of the tunnel portion 11, so that the electronic tag T of the article O in the storage portion B can be read again. Complete.

  Hereinafter, the present invention will be described specifically with reference to Examples and the like, but the present invention is not limited thereto.

<Example>
An electronic tag reader according to the present invention was manufactured based on FIGS. Specifically, as shown in FIG. 4, a passage portion 10 of the roller conveyor was provided, and a tunnel portion 11 including a left side surface 11a, a right side surface 11b, and an upper surface 11c was provided. At this time, the vertical size in the front view with respect to the passing direction of the storage box B in the tunnel portion 10 was 490 mm, and the horizontal size was 490 mm.

  Next, the antenna 12 corresponding to the UHF band RF tag is provided on each of the left side surface 11a, the right side surface 11b, and the upper surface 11c of the inner surface of the tunnel portion 11, and the transmitting surface 12a faces the inside of the tunnel portion 11. It was arranged as follows. Here, the output of the reader / writer of the control unit 15 was 30 dB, the antenna gain of the antenna 12 was 6 dBi, the plane size of the antenna 12 was 305 mm in length, and 305 mm in width.

  Further, a shield plate 13 having a circular hole 13a at the center was prepared, and the shield plate 13 was installed on the antenna 12 in front of the transmitting surface 12a of the antenna 12 so as to locate the hole 13a of the shield plate 13. Here, the plane size of the shield plate 13 was configured to be equal to the plane size of the transmitting surface 12a of the antenna 12.

  Then, a shield cloth (a thickness of 0.2 mm, made of polyethylene, copper and nickel) having a radio wave shielding effect of 41 dB at 1 GHz is used as a curtain 14 on the front 11d (entrance) and the back 11e (exit) of the tunnel portion 11, respectively. Provided.

  Here, since the leakage of the radio wave from the antenna 12 on the upper surface 11c appears most remarkably, the antenna 12 on the upper surface 11c and the electronic tag T (UHF band RF tag) of the uniform O put in the cardboard B are used. Then, the relationship between the diameter of the hole 13a of the shield plate 13 when the antenna 12 reads the information of the electronic tag T and the radio wave reach of the antenna 12 was examined.

  As a result, as shown in FIG. 5, when there is no shield plate 13 or when the diameter of the hole 13a of the shield plate 13 is 200 mm, the radio wave reach distance of the antenna 12 from which the electronic tag T can be read exceeds 1000 mm, It turned out that radio wave leakage was remarkable. On the other hand, when the diameter of the hole 13a of the shield plate 13 was 160 mm, the radio wave reach was 0 mm, and the electronic tag T could not be read.

  Therefore, when the diameter of the hole 13a of the shield plate 13 is larger than 160 mm and smaller than 200 mm (180 mm), the radio wave reach is appropriately suppressed to 400 mm, and the reading of 100 electronic tags T is performed. It turns out that it is also possible. Here, since the vertical size or the horizontal size of a general cardboard is about 500 mm, the radio wave reach of the antenna 12 on the upper surface 11 c is about 400 mm, so that the electronic tag T existing in the cardboard B can receive radio waves. Can be irradiated. Therefore, it was found that by adjusting the diameter of the hole 13a of the shield plate 13 to a predetermined value, the radio wave reach of the antenna 12 can be adjusted to the size inside the tunnel portion 11.

  Next, in each of the antennas 12 on the left side surface 11a and the right side surface 11b of the tunnel portion 11, since the influence of radio wave leakage hardly appears, the shield plate in each of the antennas 12 on the left side surface 11a and the right side surface 11b of the tunnel portion 11 is formed. The diameter of the hole 13a of the thirteenth hole was 190 mm, which was larger than the diameter of the hole 13a of the shield plate 13 in the antenna 12 on the upper surface 11c of the tunnel portion 11.

  Then, as shown in FIG. 6A, the control unit 15 (reader / writer and notebook computer) is connected to the three antennas 12 and the antennas 12 on the upper surface 11c, the left side surface 11a, and the right side surface 11b of the tunnel unit 11 are sequentially connected. An electric signal is transmitted and a radio wave is transmitted from each antenna 12. Then, another electronic tag T was set at a position 500 mm away from the entrance (front) and exit (rear) of the tunnel section 11 of the electronic tag reader 1.

  Next, 100 uniforms O with the electronic tag T are stored in the cardboard B, and the cardboard B is placed on the passing portion 10 of the electronic tag reader 1 to read the electronic tag T as shown in FIG. Was executed. Then, as shown in FIG. 7A, when the corrugated cardboard B passes through the passing portion 10 and enters the inside of the tunnel portion 11 through the front (entrance) curtain 14, the control portion 15 transmits the transmitting surfaces of the three antennas 12. By transmitting radio waves from 12a, the information of the electronic tag T of the uniform O in the corrugated cardboard B could be read simultaneously and collectively. Furthermore, surprisingly, it was confirmed that, among the information of the electronic tag T read by the control unit 15, there is no information of another electronic tag T present near the outside of the apparatus. Then, as shown in FIG. 7B, the corrugated cardboard B entered inside was conveyed to the outside through the curtain 14 on the back (exit).

  As described above, by using the electronic tag reading device 1 according to the present invention, the electronic tags T attached to each of the plurality of uniforms O in the cardboard B can be read simultaneously at the same time, and the electronic tags T existing near the outside of the device can be read simultaneously. It has been found that erroneous reading of another electronic tag T not included in the cardboard B can be reliably prevented.

  Here, as for the curtain 14, a first shield cloth (having a thickness of 0.2 mm, made of polyethylene, copper and nickel) having a radio wave shielding effect of 41 dB at 1 GHz and a second shielding cloth having a radio wave shielding effect of 70 dB at 1 GHz. When the shield cloth (having a thickness of 0.088 mm, made of polyethylene, copper, and nickel) is stacked, it is possible to further prevent radio wave leakage. For example, when the control unit 15 reads the electronic tag T in the cardboard B, even if another electronic tag T is placed at a position 200 mm or more away from either the entrance or the exit of the tunnel unit 11, the other electronic tag T There was no reading of T, and the electronic tag T in the cardboard B could be read with high accuracy.

  Therefore, the electronic tag reading device according to the present invention can reliably read the electronic tags T attached to each of the plurality of articles O in the storage box B contained in the device and prevent radio wave leakage. Therefore, it is possible to accurately perform the warehouse management and inventory management of the plurality of articles O to which the electronic tags T are attached.

  As described above, the electronic tag reading device according to the present invention can be applied to an IC tag for short-range wireless communication, as well as an RF tag in the UHF band, which is attached to each of a plurality of articles stored in a storage box. This is effective as an electronic tag reading device capable of simultaneously reading all of the electronic tags at the same time and preventing erroneous reading of other electronic tags existing near the outside of the device.

DESCRIPTION OF SYMBOLS 1 Electronic tag reader 10 Passing part 11 Tunnel part 12 Antenna 13 Shield plate 14 Curtain 15 Control part

Claims (2)

A passage portion for passing a storage box for storing articles with electronic tags,
A tunnel portion through which the storage box passes, with a part of the passage portion being a lower surface,
Of the inner surface of the tunnel portion, provided on the left side surface, the right side surface, and the upper surface with respect to the passing direction of the storage box, respectively, are installed such that a transmitting surface for transmitting a radio wave faces the inside of the tunnel portion. Antenna and
A shield plate which is formed of a radio wave absorbing plate, has a hole with a predetermined diameter in the center of the plate, and is installed so that the hole is located in front of the transmitting surface of the antenna.
It is composed of a radio-absorptive shield cloth, and is provided on each of the front and back sides of the tunnel section with respect to the passing direction of the storage box, and enables the storage box to enter and exit the tunnel section. Curtains,
A control unit that transmits radio waves from the transmitting surface of the antenna to the storage box that has entered the inside of the tunnel unit, and reads information of an electronic tag of an article in the storage box,
Equipped with a,
The diameter of the shield plate of the hole in the antenna of the upper surface of the inner surface of the tunnel portion, said tunnel portion of the inner surface of the left and right sides of each of the antenna shield plate holes of configured Ru electronic tag reader smaller than the diameter of . The electronic tag reader according to claim 1, wherein the curtain is configured by stacking two radio-absorptive shield cloths.