JP5971857B2 - Metal coil management method - Google Patents

Description

  The present invention relates to a method for managing a metal coil, and in particular, in a method for managing a metal coil using information held in an RFID tag installed in the metal coil, the RFID tag installed in the metal coil is efficiently recovered. The present invention relates to a method for managing a metal coil.

A metal coil such as a winding coil of a steel plate is generally packed after manufacturing and stored at a predetermined place address provided in a product place in the factory. Then, at the time of shipment, the winding coil to be shipped is verified after confirming that it is a predetermined product to be shipped, and then shipped.
Conventionally, a method using a bar code has been used as a method of managing a metal coil in a factory from manufacturing to shipment.

  In addition, a method using a bar code or an RFID (solid identification by radio wave) tag has been proposed as an actual item storage management system that performs storage management when a coil such as a thin steel plate is stored in a factory (for example, Patent Document 1). reference).

JP 2010-195583 A

When managing the movement of the metal coil in the factory from manufacturing to shipment using the barcode, usually the barcode written on the label attached to the metal coil is read, It is confirmed that it is a specific metal coil. However, when managing a metal coil using a barcode, it has been a problem that it takes time to read the barcode.
In order to solve this problem, it is considered that an RFID tag holding information for identifying an individual metal coil corresponding to a product number or the like is installed in the metal coil in place of the barcode, and the metal coil is managed. It is done.

  When reading information held in an RFID tag using a radio wave reader, the distance between the radio wave reader and the RFID tag can be increased to, for example, about 5 m, and compared with the distance between the bar code reader and the bar code. And can be released. In addition, when information held in an RFID tag is read using a radio wave reader, information held in a plurality of RFID tags can be read simultaneously. Therefore, when the RFID tag is used, the stored information can be easily read and the efficiency of the work for specifying the metal coil can be improved as compared with the case where the barcode is used.

The RFID tag can be easily reused by rewriting the unique information of the metal coil held on the IC (integrated circuit) chip of the RFID tag. However, in order to reuse the RFID tag, the RFID tag installed in the metal coil must be collected at the time of shipment, which has a problem that it takes time.
Moreover, in order to save the effort required for collection | recovery of an RFID tag, it is also considered not to collect the RFID tag installed in the metal coil. However, RFID tags are very expensive compared to labels with barcodes. For this reason, it is required to efficiently collect and reuse the RFID tag.

  The present invention has been made in view of such circumstances, and is installed in a metal coil in a method of managing the metal coil using information held in an RFID tag installed in the metal coil. It is an object of the present invention to provide a metal coil management method capable of efficiently collecting RFID tags.

In order to solve the above-mentioned problems, the present inventors have repeatedly studied automating the collection work of the RFID tag installed in the metal coil. As a result, by operating an automatable recovery device, the recovery device of the recovery device is made sufficiently close to the RFID tag installed in the metal coil in order to ensure that the recovery device efficiently and efficiently recovers the RFID tag. It turns out that is important.
Therefore, the inventors of the present invention are the output intensity of the radio wave supplied from the radio wave reader to the RFID tag and the communicable area which is an area where the radio wave reader can receive a signal transmitted from the RFID tag corresponding to the radio wave. Paying attention to the relationship, the following studies were repeated.

  The communicable area between the radio wave reader and the RFID tag is usually a concentric area centering on the RFID tag, and the wider the output intensity of the radio wave supplied from the radio wave reader to the RFID tag, the lower the output intensity. Narrow. Therefore, the present inventors can use a RFID tag collection device having a collection means equipped with a radio wave reader, and can communicate with a sufficiently short distance between the RFID tag to be collected as shown below. The method of bringing the collection means of the collection device closer to the RFID tag by specifying the position and installing the collection means at a communicable position was studied.

In order to identify a communicable position that is sufficiently short in distance to the RFID tag to be collected, first, radio waves are supplied to the RFID tag to be collected with a predetermined output intensity from the radio wave reader provided in the collecting means. Then, the signal transmitted from the RFID tag to be collected corresponding to the radio wave is received by the radio wave reader, and the communicable position is specified.
Next, a radio wave with reduced output intensity is supplied from the radio wave reader in the vicinity of the communicable position. Then, the signal transmitted from the RFID tag to be collected corresponding to the radio wave whose output intensity is reduced is received by the radio wave reader, and the communication with the shorter distance between the RFID tag to be collected than the communicable position is shortened. Identify possible positions.

  In addition, even if the distance between the shortened communicable position specified in this way and the RFID tag to be collected is too long and the recovery means is arranged at the shortened communicable position, the recovery that can be automated If it is difficult to reliably and efficiently collect the RFID tag in the device, the output intensity of the radio wave supplied from the radio wave reader is the same as the method for identifying the communicable position shortened in the vicinity of the communicable position. Is further reduced, and a communicable position whose distance to the RFID tag is further shortened is specified in the vicinity of the shortened communicable position. In other words, the output intensity of the radio wave from the radio wave reader is gradually reduced to narrow the range where the radio wave reader can communicate with the RFID tag to be collected, and the distance between the specified communicable position and the RFID tag is shortened. Just go.

  However, when an RFID tag is installed in a metal coil, it is difficult to specify a communicable position with a sufficiently short distance from the RFID tag to be collected by the above-described method using the output strength of radio waves. This is because the metal coil reflects radio waves between the RFID tag and the radio wave reader, and communication failure is likely to occur between the RFID tag and the radio wave reader. Therefore, in the above-described method using the output strength of radio waves, it has been difficult to reduce the distance between the RFID tag to be collected and the metal coil to 10 cm or less.

  Therefore, the present inventors have repeatedly studied to prevent poor communication between the RFID tag and the radio wave reader. As a result, if an RFID tag is installed in the cavity formed in the central axis of the metal coil, and interference with radio waves communicated with the RFID tag in the cavity is controlled by the metal coil that forms the cavity wall surface, I found a good thing.

  More specifically, when an RFID tag is installed in the cavity of the metal coil, radio waves in the width direction of the cavity communicated with the RFID tag are blocked by the metal coil, but the width direction of the metal coil, which is the length direction of the cavity The radio waves are not easily disturbed by metal coils. As a result, information communicated between the RFID tag and the radio wave reader can be prevented from being erroneously recognized. Therefore, compared to the case where the RFID tag is installed on the outermost layer of the metal coil, the output strength of the radio wave is reduced. Using the above-described method to be used, the distance between the RFID tag to be collected and the radio wave reader can be reduced to about 20 to 50 mm.

However, even when the RFID tag is installed in the cavity of the metal coil and the above-mentioned method using the output strength of the radio wave is used, even if the collection means provided with the radio wave reader is brought close to the RFID tag, the RFID tag In order to reliably and efficiently recover the tag to the recovery device, it is necessary to bring the recovery means closer to the RFID tag.
Therefore, the inventors have further studied. As a result, using an RFID tag equipped with a magnet and a radio wave reader equipped with a magnetic sensor, the radio wave reader detects the magnetism from the magnet and specifies the position of the magnet with respect to the magnetic sensor, thereby collecting the RFID tag The present invention has been conceived by finding that the distance between the radio wave reader and the radio wave reader can be sufficiently reduced.

The gist of the present invention is as follows.
(1) A tag installation step of installing an RFID tag having unique information for identifying a metal coil and provided with a magnet in a cavity formed in a central axis of the metal coil, and the RFID A management process for managing the metal coil using the unique information held in the tag, a collection means installation process for bringing the collection means for collecting the RFID tag closer to the RFID tag, and the RFID tag in the collection means And a collecting step for collecting the first radio wave from the radio wave reader provided in the collecting unit to the RFID tag and corresponding to the first radio wave from the RFID tag. By receiving the transmitted signal by the radio wave reader, a first feature for specifying a communicable position where the radio wave reader can communicate with the RFID tag. A second radio wave having a lower output intensity than the first radio wave is supplied from the radio wave reader in the vicinity of the communicable position, and a signal transmitted from the RFID tag corresponding to the second radio wave is transmitted to the radio wave. A second identification step of identifying a shortened communicable position by receiving with a reader and installing the collecting means at the shortened communicable position; and a magnet in a magnetic sensor provided in the radio wave reader And a magnetic identification step of identifying the position of the magnet with respect to the magnetic sensor by detecting the magnetism from the magnetic sensor.

(2) The metal coil management method according to (1), wherein the metal coil is made of steel and has a diameter of 900 mm to 2600 mm and a diameter of the cavity of 600 mm to 800 mm.

(3) The output intensity of the first radio wave is set to 27 dBm-30 dBm, and the output intensity of the second radio wave is set to 50 to 85% of the first radio wave. (1) or (2) Metal coil management method.

(4) The metal coil management method according to any one of (1) to (3), wherein the magnet also serves as a fixing unit that fixes the RFID tag to the metal coil.

In the metal coil management method of the present invention, since the RFID tag is installed in the cavity formed in the central axis of the metal coil, the interference with the radio wave communicated with the RFID tag in the cavity can be reduced by using the cavity wall surface. It can be controlled by the formed metal coil, and the reliability of communication between the RFID tag in the cavity and the radio wave reader can be ensured.
Further, in the metal coil management method of the present invention, since the RFID tag provided with the magnet and the radio wave reader provided with the magnetic sensor are used, in the collecting means installation step, the magnetism from the magnet is applied to the magnetic sensor. By detecting, the position of the magnet with respect to the magnetic sensor can be specified, and as shown below, the distance between the RFID tag to be collected and the radio wave reader can be sufficiently reduced.

  That is, in the metal coil management method of the present invention, the first radio wave is supplied to the RFID tag from the radio wave reader provided in the collecting means in the collecting means setting step of bringing the collecting means for collecting the RFID tag closer to the RFID tag. A first identification step of identifying a communicable position where the radio wave reader can communicate with the RFID tag by receiving a signal transmitted from the RFID tag corresponding to the first radio wave by the radio wave reader; A second radio wave having a lower output intensity than the first radio wave is supplied from the radio wave reader in the vicinity of the communicable position, and a signal transmitted from the RFID tag corresponding to the second radio wave is transmitted by the radio wave reader. By receiving the second feature, the shortened communicable position is specified, and the collecting means is installed at the shortened communicable position. The number of distances between the collection means of the collection device and the RFID tag is determined by performing a process and a magnetic identification process for identifying the position of the magnet with respect to the magnetic sensor by causing the magnetic sensor to detect magnetism from the magnet. It can be close enough with high accuracy of about mm. Therefore, according to the metal coil management method of the present invention, the RFID tag can be reliably and efficiently recovered by the recovery means by operating the recovery device. Therefore, the RFID tag can be easily collected, and the RFID tag can be easily reused.

FIG. 1A and FIG. 1B are diagrams for explaining an example of the metal coil management method of the present invention, and a schematic perspective view for explaining one step of the metal coil management method of the present invention. FIG.

Embodiments to which the present invention is applied will be described below in detail with reference to the drawings.
FIG. 1A and FIG. 1B are diagrams for explaining an example of the metal coil management method of the present invention, and a schematic perspective view for explaining one step of the metal coil management method of the present invention. FIG.

  In the management method of the metal coil 2 of the present embodiment, as shown in FIG. 1A, the RFID tag 1 holding unique information for identifying the metal coil 2 is formed on the central axis of the metal coil 2. A tag installation process installed in the cavity 2a, a management process for managing the metal coil 2 using the unique information held in the RFID tag 1, and a metal coil 2 installed as shown in FIG. The recovery means 4b for recovering the RFID tag 1 is provided with a recovery means installation step for bringing the RFID tag 1 closer to the RFID tag 1 and a recovery step for allowing the recovery means 4b to recover the RFID tag 1.

  The RFID tag 1 used in the management method of this embodiment includes an antenna for communicating radio waves with the radio wave reader 4 and an IC (integrated circuit) chip for holding unique information of the metal coil 2. Any conventionally known RFID tag may be used. For example, as the RFID tag 1, either a passive tag (passive tag) that operates using radio waves from the radio wave reader 4 as an energy source, or an active tag (active tag) equipped with a battery may be used. In addition, a passive tag does not have the effort to replace | exchange a battery like an active tag, and does not need to manage a battery remaining charge etc. FIG. For this reason, there is no inconvenience such as a decrease in the reliability of communication with the radio wave reader 4 due to the remaining battery capacity, the metal coil 2 can be easily managed with high accuracy, and the RFID tag can be reused. This is preferable because of excellent communication reliability.

  Further, as the antenna of the RFID tag 1, for example, a linear antenna type or a planar antenna type can be used. The linear antenna type has directivity in the vertical direction and the horizontal direction with respect to the antenna, and can be thinned. As a linear antenna type antenna, it is preferable to use a minute dipole or meander line. As the antenna of the meander line, specifically, trade name: manufactured by Belt UPM, trade name: manufactured by combo UPM, or the like can be used. The planar antenna type has directivity in the vertical direction with respect to the antenna, is not easily affected by metal, and can be downsized. Since the planar antenna type has directivity in the vertical direction, when the RFID tag 1 having the planar antenna type antenna is installed on the metal coil 2 with the antenna facing the central axis direction of the metal coil 2, radio waves In the communication with the reader 4, it becomes less susceptible to the influence of the metal coil 2, and when a radio wave is supplied from the radio wave reader 4 toward the central axis of the metal coil 2, a strong directivity is obtained in the direction of the radio wave from the radio wave reader 4. Therefore, the metal coil 2 can be managed with high accuracy, which is preferable.

  A magnet is provided on the outer surface of the RFID tag 1 used in the management method of the present embodiment. The magnet functions as a fixing means (not shown) for fixing the RFID tag 1 to the metal coil 2. When the RFID tag 1 has a fixing means, the RFID tag 1 and the metal coil 2 can be integrated using the fixing means, so that the RFID tag 1 is separated from the metal coil 2 due to movement of the metal coil 2 or the like. This can be prevented, and the management reliability of the metal coil 2 can be further improved. As the magnet, specifically, a rubber magnet: manufactured by Meiko Magnet Co., Ltd., a magnet plain sheet: manufactured by Meiko Magnet Co., etc. can be used.

  The fixing means is preferably a magnet, but is not limited to a magnet, and any means that can fix the RFID tag 1 to the metal coil 2 may be used, and examples thereof include an adhesive sheet. When the magnet also serves as a fixing means for fixing the RFID tag to the metal coil, the RFID tag 1 can be easily installed in the cavity 2a of the metal coil 2 so that the RFID tag 1 can be easily attached. It can be collected by the collecting means 4b of the collecting device 5, and it is preferable that scratches and marks remain on the metal coil 2 after the RFID tag 1 is removed.

In addition, a ring-shaped handle or the like may be provided on the outer surface of the RFID tag 1 in order to more reliably collect the RFID tag 1 by the collection means 4b of the collection device 5.
A light emitting device such as a light emitting diode that emits light in response to a signal from the radio wave reader 4 may be attached to the outer surface of the RFID tag 1.

  In this embodiment, unique information for identifying the metal coil 2 is held in the RFID tag 1. The unique information is not particularly limited as long as it includes unique information that can identify the metal coil 2. For example, the unique information relates to the quality of the metal coil 2 such as the product number, the material of the metal coil 2, and the manufacturing history. One or more information selected from information, information related to management such as the product address of the metal coil 2, and information related to the use and shipping date of the metal coil 2 can be used.

As a method for holding the unique information for identifying the metal coil 2 in the RFID tag 1, as shown in FIG. 1A, a radio wave corresponding to the unique information is supplied from the radio wave reader 4 to the RFID tag 1 with a predetermined output intensity. In addition, there is a method in which the RFID tag 1 receives the antenna and writes the unique information to the IC chip.
As a radio wave used for information communication between the RFID tag 1 and the radio wave reader 4, it is preferable to use an ultra high frequency (UHF).
The radio wave reader 4 may be any conventionally known radio wave reader 4 as long as it can communicate information with the RFID tag 1.

  Examples of the metal coil 2 managed using the management method of the present embodiment include those made of a steel material such as a hot rolled coil. In addition, the metal coil 2 is not limited to what consists of steel materials, You may consist of other metal materials, such as Al, Al alloy, stainless steel, and titanium.

A metal coil 2 shown in FIG. 1 has a cylindrical shape, and a cavity 2 a is formed along the central axis of the metal coil 2. Although the dimension of the metal coil 2 is not specifically limited, It is preferable that the diameter d1 is 900 mm-2600 mm, and the diameter d2 of the cavity 2a is 610 mm-800 mm (24 inches-30 inches).
When the metal coil 2 is made of steel and the diameter d1 and the diameter d2 of the cavity 2a are within the above ranges, the thickness of the metal coil 2 forming the wall surface of the cavity 2a is sufficiently thick. The radio wave in the width direction of the cavity 2a communicated with the RFID tag 1 can be sufficiently prevented. Therefore, interference with the radio wave communicated with the RFID tag 1 in the cavity 2a can be effectively prevented, and information communicated between the RFID tag 1 and the radio wave reader 4 can be prevented from being erroneously recognized.

Further, when the diameter d2 of the cavity 2a is 610 mm or more, radio waves in the length direction (width direction of the metal coil 2) of the cavity 2a communicated with the RFID tag 1 are not easily disturbed by the metal coil 2. Therefore, communication of information between the RFID tag 1 and the radio wave reader 4 can be performed with higher accuracy.
Further, when the diameter d1 of the metal coil 2 is 2600 mm or less, when a plurality of metal coils in which RFID tags are installed are arranged in the cavity with the extending direction of the central axis aligned, they are installed in a plurality of adjacent metal coils. The distances between the RFID tags 1 thus made can be arranged close to each other easily. For this reason, the information held in the RFID tags 1 of a plurality of adjacent metal coils can be easily read simultaneously using the radio wave reader 4, and the efficiency is improved when there are a plurality of metal coils 2 to be managed. Can manage well.

  In the present embodiment, as shown in FIG. 1A, the RFID tag 1 holding unique information for identifying the metal coil 2 is installed in the cavity 2 a of the metal coil 2. A method for installing the RFID tag 1 in the cavity 2a of the metal coil 2 is not particularly limited, but it is preferable to operate by operating an automatable machine such as a robot. In this embodiment, since the RFID tag 1 is installed in the cavity 2a of the metal coil 2, the RFID tag 1 may become dirty as compared with the case where the RFID tag 1 is installed in a place other than the cavity 2a of the metal coil 2. It can be prevented from being damaged, the management reliability of the metal coil 2 can be further improved, and the number of times the RFID tag 1 is reused can be increased. In the present embodiment, since the RFID tag 1 is installed in the cavity 2a of the metal coil 2, the RFID tag 1 can be prevented from moving away from the metal coil 2 due to movement of the metal coil 2, etc. The reliability of management can be further improved.

  Next, the metal coil 2 is managed using the unique information held in the RFID tag 1 (management process). Specifically, for example, a radio wave of a predetermined output intensity is supplied from the radio wave reader 4 to the RFID tag 1 before the metal coil 2 is moved, during the movement, after the movement, before and after packing, and at the time of shipment. Then, the unique information is read from the RFID tag 1, and the metal coil 2 is specified by using the obtained unique information, thereby managing the metal coil 2.

  In this embodiment, since the RFID tag 1 is installed in the cavity 2a of the metal coil 2, radio waves in the width direction of the cavity 2a communicated with the RFID tag 1 are blocked by the metal coil 2, but the length of the cavity 2a. The direction of the radio wave in the width direction of the metal coil 2 is not easily disturbed by the metal coil 2. As a result, information communicated between the RFID tag 1 and the radio wave reader 4 is prevented from being erroneously recognized, and the metal coil 2 can be easily identified and managed with high accuracy.

Next, the metal coil 2 managed in this way is shipped. In the present embodiment, the RFID tag 1 installed on the metal coil 2 to be shipped is collected.
In order to recover the RFID tag 1, first, as shown in FIG. 1B, the recovery means 4b for recovering the RFID tag 1 installed in the metal coil 2 is brought close to the RFID tag 1 (recovery means installation step). ).

  The recovery means 4b shown in FIG. 1 (b) recovers the RFID tag 1, and is attached to the tip of the articulated arm of the recovery device 5 that can be automated. The multi-joint arm has an outer periphery that is sufficiently narrower than the inner periphery of the cavity 2 a of the metal coil 2, and has a shape that allows entry into the cavity 2 a of the metal coil 2. The articulated arm is controlled by a control device such as a PC (Personal Computer), and moves according to a signal from the radio wave reader 4a received by the control device.

  Further, as shown in FIG. 1B, a radio wave reader 4a is attached to the collecting means 4b. And the collection | recovery means 4b and the electromagnetic wave reader | leader 4a can be moved to arbitrary directions up and down, right and left, and back by moving the articulated arm of the collection | recovery apparatus 5 in the integrated state. The radio wave reader 4a is attached with a magnetic sensor for detecting magnetism from a magnet provided in the RFID tag 1.

  The radio wave reader 4a provided in the collecting means 4b can communicate information with the RFID tag 1 and can adjust the output intensity of the radio wave supplied to the RFID tag 1 so far. Any of these may be used. The radio wave reader 4a may be the same as or different from the radio wave reader 4 shown in FIG. 1A used when the RFID tag 1 holds the unique information. Moreover, it is preferable that the radio wave reader 4a can communicate information with a control device such as a sequencer that realizes sequence control.

  The magnetic sensor may be any conventionally known one as long as it can detect magnetism from a magnet provided in the RFID tag 1, and for example, a Hall effect type magnetic sensor can be used. Specifically, Hall IC EM-1771 (made by Asahi Kasei Electronics Co., Ltd.) etc. can be used as a magnetic sensor.

  The collecting means 4b may be any means as long as it can collect the RFID tag 1, and can be determined according to the shape of the RFID tag 1 and is not particularly limited. For example, the collection means 4b has a pair of opposing members arranged opposite to each other, and the interval between the opposing members can be changed. By interposing the RFID tag 1 between the opposing members, the RFID tag It may be one that can be held and collected. For example, when the RFID tag 1 is provided with a ring-shaped handle on the outer surface, the collecting means 4b may be a hook that can be inserted into the ring-shaped handle.

In the method of bringing the collection means 4b shown in FIG. 1B close to the RFID tag 1, is there any other metal coil on which the RFID tag is installed around the metal coil 2 where the RFID tag 1 is to be collected? It depends on whether or not.
In the present embodiment, the RFID tags 11 and 12 are installed in the cavities 21a and 22a on both sides in the width direction of the cavity 2a of the metal coil 2 from which the RFID tag 1 is to be collected, as shown in FIG. A case where the metal coils 21 and 22 are disposed will be described as an example. As shown in FIG. 1 (b), the metal coils 2, 21, and 22 are aligned in the extending direction of the central axis of the metal coils 2, 21, and 22 and the positions of the ends of the cavities 2a, 21a, and 22a. Are lined up.

  In addition, in FIG.1 (b), although the case where the three metal coils 2, 21, and 22 were installed by aligning the extending direction of the central axis and the position of the end of the cavity was described as an example, Other metal coils may not be arranged around the metal coil 2 for which the RFID tag 1 is to be collected, and other metal coils are disposed only on one side in the width direction of the cavity 2a of the metal coil 2 for which the RFID tag 1 is to be collected. It may be arranged, or four or more metal coils may be aligned with the extending direction of the central axis and the position of the end of the cavity aligned. Further, when a plurality of metal coils are installed around the metal coil 2 from which the RFID tag 1 is to be collected, the extending direction of the central axis of all or some of the metal coils and / or the position of the end of the cavity are , It does not have to be aligned.

In the present embodiment, an example will be described in which the RFID tag 1 of the metal coil 2 to be shipped is recovered from among the RFID tags 1, 11, and 12 installed in the plurality of metal coils 2, 21, and 22, respectively. To do. Therefore, in the collection means installation step of this embodiment, the collection means 4b is brought close to the RFID tag 1 of the metal coil 2 to be shipped among the plurality of metal coils 2, 21, and 22.
In the collection means installation step of this embodiment, a communicable position that can communicate with the RFID tag 1 of the radio wave reader 4a provided in the collection means 4b is identified (first identification process), and then the communicable position is determined. The shortened communicable position is specified in the vicinity, and the collecting means 4b is installed at the shortened communicable position (second identifying step).

  Moreover, in the collection | recovery means installation process of this embodiment, the position of the magnet with respect to a magnetic sensor is pinpointed by making the magnetic sensor with which the radio wave reader 4a is equipped detect the magnetism from the magnet with which the RFID tag 1 was equipped. A magnetic identification process is performed. In addition, before performing a 1st specific process, while performing a 1st specific process and / or a 2nd specific process, a magnetic specific process is between a 1st specific process and a 2nd specific process, and a 2nd specific process. It may be performed at any time selected later. In addition, the magnetic identification process may be performed continuously during the collection means installation process, or may be performed once or a plurality of times at any one or more times described above. In order to make the distance between the RFID tag and the metal coil closer, it is preferable to perform a magnetic identification process after the second identification process to move the radio wave reader 4a relatively toward the RFID tag 1. .

  In the first specifying step, first, the collecting unit 4b is moved to move the radio wave reader 4a provided in the collecting unit 4b and the RFID tag 1 to be collected while relatively moving the positional relationship between the radio wave reader 4a and the collecting unit 4b. A radio wave (first radio wave) is supplied to the RFID tag 1 desired to be transmitted at a predetermined output intensity. And the communicable position is specified by receiving the signal transmitted from the RFID tag 1 to be collected corresponding to the first radio wave by the radio wave reader 4a.

  In the present embodiment, as shown in FIG. 1B, the metal coils 21 and 22 on which the RFID tags 11 and 12 are installed are arranged on both sides in the width direction of the cavity 2a of the metal coil 2. In the first specifying step, the radio wave reader 4a is opposed to the end faces of the metal coils 2, 21, 22 and the width direction of the cavity 2a of the metal coils 2, 21, 22 (in the direction of arrow A in FIG. 1B). When the first radio wave is supplied from the radio wave reader 4a while being moved, not only the signal transmitted from the RFID tag 1 to be collected but also the metal coils 21 and 22 corresponding to the radio wave supplied from the radio wave reader 4a is installed. In some cases, signals transmitted from the RFID tags 11 and 12 are received by the radio wave reader 4a. In this case, for example, it is possible to determine whether or not the signal is transmitted from the RFID tag 1 to be collected by the following method, and to communicate with the RFID tag 1 of the radio wave reader 4a provided in the collecting unit 4b. Specify a communicable position.

  As a method for determining whether or not the signal is transmitted from the RFID tag 1 to be collected, for example, a radio wave reader 4a that can communicate information with a control device such as a PC (personal computer). The signal from the RFID tag 1 of the metal coil 2 to which the unique information of each metal coil included in the signal transmitted from the plurality of RFID tags to the radio wave reader 4a is transmitted to the control device and each signal is shipped by the control device. There is a method for determining whether or not.

  In addition, the magnet for the magnetic sensor obtained based on the magnetic information from the magnet read by the magnetic sensor when the magnetic identification step is performed before the first identification step or during the first identification step. The radio wave reader 4a can be relatively moved toward the RFID tag 1 to be collected by moving the collection means 4b toward the magnet provided in the RFID tag 1 according to the position of the RFID tag 1. Therefore, the signal transmitted from the RFID tag 1 desired to be collected in response to the first radio wave can be easily received by the radio wave reader 4a, and the communicable position can be specified easily and efficiently. In addition, by detecting the position of the magnet with respect to the magnetic sensor and moving the radio wave reader 4a toward the RFID tag 1 within a communicable area that is an area in which the signal transmitted from the RFID tag 1 can be received by the radio wave reader 4a. The distance between the RFID tag 1 to be collected and the radio wave reader 4a can be further reduced.

  Then, a 2nd specific process is performed. In the second specifying step, a second radio wave having an output intensity lower than that of the first radio wave is supplied from the radio wave reader 4a near the communicable position. The radio wave reader 4a receives a signal transmitted from the RFID tag 1 to be collected corresponding to the second radio wave, and specifies a shortened communicable position. After that, the collecting means 4b is installed at the shortened communicable position. As a result, the recovery means 4b is brought closer to the RFID tag 1 that is desired to be recovered.

  In this embodiment, since the RFID tags 1, 11, and 12 are installed in the cavities 2a, 21a, and 22a formed on the central axes of the metal coils 2, 21, and 22, the RFID tag 1 in the cavity 2a. Can be controlled by the metal coil 2 forming the wall surface of the cavity 2a, and the reliability of communication between the RFID tag 1 in the cavity 2a and the radio wave reader 4a can be ensured. Therefore, it is possible to prevent erroneous recognition of information communicated between the RFID tag 1 and the radio wave reader 4a. Therefore, the output intensity of the radio wave supplied from the radio wave reader 4a can be sufficiently reduced, and a communicable position with a sufficiently short distance from the RFID tag 1 to be collected can be specified with high accuracy.

  In addition, the magnet for the magnetic sensor detected by the magnetic sensor when the magnetic identification process is performed before the second identification process is performed after the first identification process is performed or during the second identification process. Since the collection means 4b can be moved toward the magnet provided in the RFID tag 1 according to the position of the signal, the signal transmitted from the RFID tag 1 to be collected corresponding to the second radio wave is transmitted to the radio wave reader 4a. Thus, it is possible to easily receive, and it is possible to easily and efficiently specify a communicable position. In addition, by detecting the position of the magnet with respect to the magnetic sensor and moving the radio wave reader 4a toward the RFID tag 1 within a communicable area that is an area in which the signal transmitted from the RFID tag 1 can be received by the radio wave reader 4a. The distance between the RFID tag 1 to be collected and the radio wave reader 4a can be further reduced.

  Further, when the magnetic identification step is performed after the second identification step and the radio wave reader 4a is moved relatively toward the RFID tag 1 to be collected, the distance between the RFID tag 1 to be collected and the radio wave reader 4a is further increased. You can get closer.

  It should be noted that even if the distance between the shortened communicable position identified in the second identifying step and the RFID tag 1 to be collected is too long and the recovery means 4b is arranged at the shortened communicable position, the recovery is possible. When it is difficult for the device 5 to reliably and efficiently collect the RFID tag 1, the radio wave supplied from the radio wave reader 4 a is the same as the method of identifying the communicable position shortened in the vicinity of the communicable position. Is further reduced, and a communicable position where the distance to the RFID tag 1 is further shortened is specified in the vicinity of the shortened communicable position.

In the present embodiment, it is preferable that the output intensity of the first radio wave is, for example, 27 dBm-30 dBm (500 mW to 1 W), and the output intensity of the second radio wave is, for example, 20 dBm to 23 dBm (100 mW to 200 mW).
If the output intensity of the first radio wave is within the above range, a sufficient communicable area between the radio wave reader 4a and the RFID tag 1 in the first identification process can be secured, and the communicable position can be identified easily and efficiently. In addition, the distance between the RFID tag 1 to be collected and the communicable position is sufficiently short, the communicable position shortened with high accuracy in the second identification process can be identified, and the shortened communicable position and the RFID tag to be collected 1 is preferable because the distance to 1 is short. The output intensity of the first radio wave is particularly preferably 30 dBm (1 W) in order to ensure a sufficient communication area between the radio wave reader 4 a and the RFID tag 1.

  The output intensity of the second radio wave is preferably 50 to 85% of the first radio wave. If the output intensity of the second radio wave is 50% or more of the first radio wave, a sufficient communicable area between the radio wave reader 4a and the RFID tag 1 in the second specific process can be secured, and communication can be easily and efficiently performed. Possible positions can be specified. Further, when the output intensity of the second radio wave is 85% or less of the first radio wave, the distance from the RFID tag 1 to be collected is sufficiently shorter than the communicable position by performing the second specifying step. A shortened communicable position is obtained.

  In addition, when a step of specifying a communicable position whose distance to the RFID tag 1 is further shortened in the vicinity of the shortened communicable position after the second specifying step, the radio wave reader is used in this step. The output intensity of the radio wave supplied from 4a is preferably 50 to 81% of the second radio wave. In addition, when performing the step of identifying a communicable position whose distance to the RFID tag 1 is further shortened in the vicinity of the shortened communicable position once or more, when identifying the communicable position at the end The output intensity of the radio wave supplied from the radio wave reader 4a is preferably 10 dBm-17 dBm (10 mW to 70 mW).

  Next, a collecting step for collecting the RFID tag 1 by the collecting unit 4b is performed. In the present embodiment, since the recovery unit 4b is sufficiently close to the RFID tag 1 that is desired to be recovered, the RFID tag 1 can be reliably and efficiently recovered by the recovery unit 4b by operating the recovery device 5. it can. Therefore, the RFID tag 1 can be easily collected, and the RFID tag 1 can be easily reused.

"Example 1"
Three metal coils 2 shown in FIG. 1 (a) having a diameter of 2100 mm and a cavity diameter of 762 mm made of steel are prepared, and the extension direction of the central axis and the position of the end of the cavity are aligned, and adjacent metal coils are aligned. They were arranged with an interval of 2500 mm.
In addition, three RFID tags (trade name: YS-A2AOT0-T3, manufactured by Yoshikawa Kogyo), which are passive tags provided with magnets as fixing means on the outer surface, are prepared, and a radio wave reader 4 (trade name: URP-SJ110 (stock) ) (Made by Welcat) was used to hold unique information for identifying each metal coil.

Thereafter, as shown in FIG. 1 (b), RFID tags 1, 11, and 12 were installed in cavities 2a, 21a, and 22a formed along the central axes of the metal coils 2, 21, and 22, respectively. In the first embodiment, the RFID tags 1, 11, and 12 are installed on the metal coils with the antennas directed toward the central axes of the metal coils a, 21a, and 22a.
Next, the collection means 4b was brought close to the RFID tag 1 installed on the metal coil 2 by the method described below (collection means installation step).
As the recovery means 4b, as shown in FIG. 1 (b), the one attached to the tip of the articulated arm of the recovery device 5 was used. Further, as shown in FIG. 1 (b), the collection means 4b includes a radio wave reader 4a (trade name: URP-SJ110, manufactured by Welcat Corporation) equipped with a Hall IC EM-1771 (manufactured by Asahi Kasei Electronics Co., Ltd.) as a magnetic sensor. ) Was attached.

In the collection means installation step, the magnetic identification process was continuously performed after the first identification process and before the collection means installation process was completed before the second identification process was performed.
More specifically, first, the radio wave reader 4a is opposed to the end faces of the metal coils 2, 21, and 22, and the width direction of the cavity 2a of the metal coils 2, 21, and 22 (the direction of arrow A in FIG. 1B). The radio wave (first radio wave) was supplied with a predetermined output intensity to the RFID tag 1 to be collected from the radio wave reader 4a. And the communicable position was specified by receiving the signal transmitted from the RFID tag 1 to be collected corresponding to the first radio wave by the radio wave reader 4a (first specifying step).

Next, the magnetic identification process is started, and the magnetic sensor provided in the radio wave reader 4a is caused to detect magnetism from the magnet provided in the RFID tag 1, and the magnetic information read from the magnet is read by the magnetic sensor. Based on this, the position of the magnet relative to the magnetic sensor was identified.
Subsequently, in accordance with the position of the magnet with respect to the magnetic sensor, the output means 4b has a higher output intensity than the first radio wave from the radio wave reader 4a in the vicinity of the communicable position while moving the collection means 4b toward the magnet provided in the RFID tag 1. A low second radio wave was supplied. Then, the signal transmitted from the RFID tag 1 desired to be collected corresponding to the second radio wave is received by the radio wave reader 4a, and the shortened communicable position is specified (second specifying step).

  Thereafter, the collection means 4b is moved toward the magnet provided in the RFID tag 1 in accordance with the position of the magnet with respect to the magnetic sensor specified based on the magnetic information from the magnet read by the magnetic sensor. 2 In the same manner as in the specifying process, the output intensity of the radio wave supplied from the radio wave reader 4a is further reduced a plurality of times, and the distance to the RFID tag 1 is further reduced in the vicinity of the shortened communicable position. Identified a location where communication is possible.

  Thereafter, the position of the magnet with respect to the magnetic sensor was detected in the communicable area, which is an area where the signal transmitted from the RFID tag 1 can be received by the radio wave reader 4a, and the radio wave reader 4a was moved toward the RFID tag 1.

In the first embodiment, the output intensity of the first radio wave is 30 dBm (1 W), the output intensity of the second radio wave is 24 dBm (250 mW), and the last specified reduced communicable position is specified. The output intensity of the radio wave supplied from the radio wave reader 4a was 20 dBm (100 mW).
The distance between the RFID tag 1 and the shortened communicable position specified last was measured. As a result, it was 50 mm.

Further, the distance between the radio wave reader 4 and the RFID tag 1 after detecting the position of the magnet with respect to the magnetic sensor and moving the radio wave reader 4a toward the RFID tag 1 from the shortened communicable position specified last. It was measured. As a result, it was 10 mm.
From this, it was confirmed that the distance between the radio wave reader 4a of the recovery means 4b and the RFID tag 1 can be reduced to 10 mm by performing the recovery means installation step.

“Experiment 1”
Five metal coils 2 shown in FIG. 1A having a diameter of 2100 mm and a hollow diameter of 762 mm made of steel are prepared, and five RFID tags equipped with antennas (trade name: YS-A2AOT0, manufactured by Yoshikawa Kogyo) are prepared. Each of them has its own unique information.
Next, each RFID tag was placed on the metal coil with the antenna facing in the direction of the central axis of the metal coil.

  Next, along the substantially extending direction of the cavity of the metal coil 2, the position of supplying the radio wave of the radio wave reader 4 (trade name URP-SJ110 Co., Ltd., Welcat) is brought close to the cavity of the metal coil 2. The unique information is read from each RFID tag with the output intensity (electric power (dBm)) of the radio wave shown in FIG. 5 and the readable distance of each RFID tag with respect to the output intensity (electric energy (dBm)) of the radio wave is measured.

"Experiment 2"
Except for using (trade name: YS-A2AOT1, manufactured by Yoshikawa Kogyo Co., Ltd.) as an antenna, the readable distance of each RFID tag with respect to the radio wave output intensity (power (dBm)) was measured in the same manner as in Experiment 1. .
The results are shown in Table 1.

“Experiment 3”
The unique information was read from each RFID tag while the position where the radio wave reader 4 supplied the radio wave was close to the outermost metal band of the metal coil 2 along the direction substantially perpendicular to the extending direction of the cavity of the metal coil 2. Except for this, in the same manner as in Experiment 1, the readable distance of each RFID tag with respect to the output intensity of radio waves (power amount (dBm)) was measured.

“Experiment 4”
Except that the same antenna as in Experiment 2 was used, the readable distance of each RFID tag with respect to the output intensity (electric power (dBm)) of the radio wave was measured in the same manner as in Experiment 3.
The results are shown in Table 2.

"Experiment 5"
Except for using (trade name: YS-A2AOT4, manufactured by Yoshikawa Kogyo Co., Ltd.) as an antenna, the readable distance of each RFID tag with respect to the output intensity (electric power (dBm)) of the radio wave was measured in the same manner as in Experiment 3. .

“Experiment 6”
Except for using the same antenna as in Experiment 5, the readable distance of each RFID tag with respect to the radio wave output intensity (power amount (dBm)) was measured in the same manner as in Experiment 1.
The results are shown in Table 3.

“Experiment 7”
Except that the RFID tag was installed on the metal coil with the antenna facing in the direction perpendicular to the central axis of the metal coil, the RFID tag was measured for each radio wave output intensity (power (dBm)) in the same manner as in Experiment 5. Readable distance was measured.

“Experiment 8”
Except that the RFID tag is placed on the metal coil with the antenna facing in the direction perpendicular to the central axis of the metal coil, the RFID tag is measured with respect to the output intensity (electric power (dBm)) of the radio wave in the same manner as in Experiment 6. Readable distance was measured.
The results are shown in Table 4.

  As shown in Tables 1 to 4, when the RFID tag is placed in the cavity of a metal coil, the readable distance of the RFID tag is shortened by reducing the output intensity (electric energy (dBm)) of the radio wave. It was confirmed that the distance between the RFID tag and the metal coil to be collected by using the output strength of the radio wave can be reduced to some extent.

  DESCRIPTION OF SYMBOLS 1, 11, 12 ... RFID tag 2, 21, 22 ... Metal coil, 2a, 21a, 22a ... Cavity 4, 4a ... Radio wave reader, 4b ... Collection means.

Claims (4)

A tag installation step of installing an RFID tag having magnets provided with unique information for identifying a metal coil in a cavity formed in the central axis of the metal coil;
A management step of managing the metal coil using the unique information held in the RFID tag;
A collection means for collecting the RFID tag, a collection means installation step for bringing the RFID tag close to the RFID tag,
A recovery step of recovering the RFID tag in the recovery means,
In the collecting means installation step, a first radio wave is supplied to the RFID tag from a radio wave reader provided in the collecting means, and a signal transmitted from the RFID tag corresponding to the first radio wave is transmitted by the radio wave reader. A first specifying step of specifying a communicable position capable of communicating with the RFID tag of the radio wave reader by receiving;
A second radio wave having a lower output intensity than the first radio wave is supplied from the radio wave reader near the communicable position, and a signal transmitted from the RFID tag corresponding to the second radio wave is received by the radio wave reader. A second specifying step of identifying a shortened communicable position and installing the collecting means at the shortened communicable position;
And a magnetic identification step of identifying a position of the magnet with respect to the magnetic sensor by causing a magnetic sensor provided in the radio wave reader to detect magnetism from the magnet. Method.   The metal coil management method according to claim 1, wherein the metal coil is made of a steel material and has a diameter of 900 mm to 2600 mm and a diameter of the cavity of 600 mm to 800 mm.   3. The metal coil according to claim 1, wherein the output intensity of the first radio wave is 27 dBm-30 dBm, and the output intensity of the second radio wave is 50 to 85% of the first radio wave. Management method.   The metal magnet management method according to claim 1, wherein the magnet also serves as a fixing unit that fixes the RFID tag to the metal coil.

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