JP2012062143A - Automatic reader and automatic reading system using forklift - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic reader that directly reads the information of an article attached with an IC tag which is stored in a multi-story warehouse or multi-level storage warehouse such as an existing high-rise warehouse or an automated warehouse, and an automatic reading system using a forklift.SOLUTION: The automatic reader 20 which reads the information of RF tags 41 and 42 of an article stored in a warehouse 40 and collects these pieces of information, has a base plate having a space into which a fork 15 of the forklift 10 is inserted, a specified number of RF tag reading antennas 23 which are arranged in a direction crossing the direction of the framework space formed at the base plate into which the fork 15 is inserted, at a specified interval at least in the height direction, and a controller 24 which has a means for sending information acquired by the antennas 23. The antennas 23 are arranged according to a shelf interval of the warehouse 40.

Description

  The present invention relates to an automatic reading system using an automatic reading device and a forklift, and in particular, an automatic reading device and an automatic using a forklift which can be applied as they are without any modification even in conventional three-dimensional warehouses and multistage warehouses. The present invention relates to a reading system.

  Conventionally, a barcode system has been known as an automatic recognition technology for identifying and confirming the storage position of articles in a high-rise, multi-level warehouse such as a three-dimensional warehouse or an automatic warehouse and grasping the quantity. This bar code system reads bar code information for each one individually. For this reason, in many scenes of article identification, it took a lot of manpower and time.

On the other hand, using an IC tag instead of a bar code system, it is possible to specify all articles and their location in the area while moving the device body even in a large area. A technique has been proposed that can reliably collect information about where and what is in an area (Patent Document 1).
In addition, when performing an article warehousing process, a moving process, and an unloading process with a forklift truck, the position tag of the placement area that is equipped on the forklift and designated as the transport source and the transport destination, and the position stored in the article tag A technique for reading information and article information and updating location information stored in a computer device based on the position information and article information has been proposed (Patent Document 2).
Further, a technique has been proposed in which information of an IC tag mounted on a forklift and attached to a luggage or the like is read without contact (Patent Documents 3 and 4).

  In the technique of Patent Document 1, the radio wave transmission / reception range is varied while the apparatus main body is moved and moved, and the IC tag is assigned when searching for an IC tag existing within the variable search range. The relative position between the article and the apparatus main body is detected to identify the location of the article. And with the technology of collecting and storing the article location and the article identification information read from the IC tag in association with each other, even if it is a large area, it simply passes through the area while moving the device body. Therefore, it is possible to automatically identify all the articles present in this area and their location, and it is possible to reliably collect information about where and what is in the area, and based on this collected information It is expected that materials such as the presence status and inventory status of articles existing in the site can be created.

  In the technique of Patent Document 2, each placement area unit includes a plurality of placement areas formed in a row in a warehouse, and pallets embedded in the edges of each placement area and placed in each placement area. A plurality of article tags for performing processing for storing article information such as numbers and article numbers, processing for transferring article information to and from the mounting device by wireless signals, and each placement area embedded in the edge of each placement area And a plurality of position tags for supplying the position information to the mounting apparatus by wireless signals. When a wireless signal including a position information request is transmitted from the mounting device of the forklift truck, a wireless signal including position information is transmitted from a position tag facing the mounting device among the position tags, and from the mounting device. When a radio signal including an article information request is transmitted, a radio signal including article information is transmitted from an article tag facing the mounting apparatus among the article tags, and radio including new article information from the mounting apparatus. When a signal is transmitted, this is a technique for capturing an article tag facing an on-board device and updating the article information stored so far.

  The technology of Patent Document 3 enables transmission / reception of signals between an IC tag attached to a pallet or luggage and an antenna located above via a reflector, and the signal emitted from the IC tag is reflected by the reflector. Thus, the reader / writer reads the information written in the IC tag from the signal received by the antenna.

  In the technique of Patent Document 4, a reader / writer installed in a main body, which is a non-movable part of a forklift for carrying a load, reads rack identification information from an RFID tag, and an information processing unit reads the rack information read by the reader / writer. Acquires the identification information and the position information of the radio wave blocking plate that blocks the radio wave emitted when the reader / writer reads the rack identification information, and stores the package based on the position information of the radio wave blocking plate and the rack identification information. This is a technique for discriminating the position of a rack to be processed or the position of a rack to be picked up.

Japanese Patent Laying-Open No. 2005-320074 (see paragraphs 0005 and 0014, FIG. 2) JP 2000-255714 A (see paragraph 0025, FIG. 1 and FIG. 2) JP 2007-320704 A (see paragraphs 0015 and 0025, FIGS. 1 to 3 and FIG. 8) International Publication No. 06/070460 (Summary, see Figure 1)

However, the technique of Patent Document 1 cannot be immediately mounted on a forklift, requires a moving means other than the forklift, and the apparatus main body has a configuration in which a cylindrical rotating member is rotatably arranged in a plurality of stages. These rotating members are pivotally supported in a 360 ° range so that they can be rotated in the forward and reverse directions, and one RFID reader is attached to each side surface portion, and the structure is complicated.
The technique of Patent Document 2 is a technique based on an IC tag embedded in the edge (floor) of the mounting area and cannot be applied to an existing warehouse or the like.
Furthermore, the technologies of Patent Document 3 and Patent Document 4 are based on the premise of reading a tag on the front surface of a forklift, and use forklifts to handle luggage stored in high-rise, multi-level warehouses such as three-dimensional warehouses and automatic warehouses. It is something that cannot be done. That is, when an antenna for reading is attached to the front surface of the forklift, it is suitable for receipt / shipment management. That is, it is suitable for incoming / outgoing management of individual articles (goods) by reading what is loaded on the forklift, but it is necessary to direct the forklift to the front of the warehouse shelf (the surface on which the tag is attached) for inventory management. There is. As described above, generally, tags / barcodes on warehouse shelves are grasped by reading them individually with a barcode reader or handy reader (to some extent in UHF), but it takes a lot of time and effort and is quick. There is an inconvenience that it lacks.

The present invention has been made in view of the above-described problems, and the object thereof is to use as it is a package with an IC tag stored in a high-rise, multi-level warehouse such as an existing three-dimensional warehouse or automatic warehouse. To provide an automatic reading system using an automatic reading device and a forklift.
Another object of the present invention is to provide an automatic reading apparatus and an automatic reading system using a forklift capable of reading at a stretch a package with an IC tag stored in a high-rise, multistage warehouse such as a three-dimensional warehouse or an automatic warehouse using a forklift. Is to provide.

  According to the automatic reading device of the present invention, the subject is an automatic reading device that collects information by reading information of RF tags of articles stored in a warehouse, and includes a space in which a fork of a forklift can be inserted. A base, a frame disposed on the base, and a predetermined number of at least in the height direction at predetermined intervals in a direction intersecting the direction of the space in which the fork of the frame can be inserted An RF tag reading antenna and a control device having means for transmitting information acquired by the antenna, wherein the antenna is arranged in accordance with the interval between warehouse shelves, It is solved by.

With this configuration, the automatic reading device can be mounted on the forklift in the same manner as holding a normal pallet, and the automatic reading device can be mounted in the direction of the space in which the forklift can be inserted. Since the antennas arranged in the intersecting direction are arranged in accordance with the interval between the warehouse shelves, the information of the RF tag of the article on the side surface of the forklift is read and collected only by traveling on the forklift. It becomes possible.
For this reason, forklifts that take in and out goods (luggage) can be used to manage logistics by reading RF tags in existing high-rise, multi-level warehouses such as three-dimensional warehouses and automatic warehouses without any modification. Is possible.

At this time, it is preferable that the control device is configured to control the reading range of the RF tag according to the transmission output or the radiation gain, radiation characteristics, and mounting direction of the antenna.
Further, it is preferable that the control device is configured to compare an RSSI by the antenna and identify an RF tag to be read and another non-target read RF tag.
Further, it is preferable that the control device is configured such that the forklift passes only in front of the RF tag so as to recognize only the desired tag without recognizing other overread surrounding tags.
The control device recognizes the relative distance between the target RF tags based on the magnitude of the time difference between the peak apexes using the graph of the radio wave reception characteristics of the antenna that draws the peak of the received signal intensity in time series. It is preferable to constitute so.
Further, when the moving means or tag having the antenna moves, it is detected that the radio wave reception intensity changes in time series due to radio wave reflection or the like, and recognizes the movement or stationary of the forklift or the RF tag. Configure as follows.
In addition, using the fact that the radio wave reception signal strength draws a mountain-shaped graph in time series according to the radio wave radiation characteristics of the antenna, the moving means having the antenna for reading is placed in a shelf number tag (a specific easy-to-read position on the shelf). Crossing the front of the label), the return signal strength (RSSI) of the shelf number tag is used as a reference value to facilitate identification of other non-target reading tags and desired reading tags, and other non-target readings. It is preferable to configure so that only a desired tag is identified without recognizing surrounding tags as tags.
Further, it is preferable that the forklift has a function of identifying the position on the plane of the forklift and the position of the vertical surface of the forklift by reading the shelf number tag attached to a specific easy-to-read position on the shelf of the warehouse. .

  The subject is an automatic reading system using a forklift according to the present invention, wherein the automatic reading device according to claim 1 is mounted on a fork of a forklift and the forklift is driven to read an RF tag. An RF tag provided on an article and a shelf by the antenna, wherein the forklift is driven to turn on the automatic reading device and run between the shelves of a warehouse storing the article by the forklift. And storing the read information to the outside, moving the forklift to move the plane, and moving the forklift lift up to move in the vertical direction. It was possible to read RF tags on the left, right, top and bottom of Ri is resolved.

  According to the present invention, it is possible to collect information by reading the RF tag information of the article on the side of the forklift only by traveling on the forklift. Thus, it is possible to carry out physical distribution management by reading RF tags for existing high-rise, multi-level warehouses such as three-dimensional warehouses and automatic warehouses without any modification.

It is explanatory drawing of the automatic reading system using the automatic reading apparatus and forklift which concern on this invention. It is explanatory drawing of the automatic reading system using the automatic reading apparatus and forklift which concern on this invention. It is explanatory drawing of the automatic reader of the state which removed the frame. It is explanatory drawing of the automatic reader from a forklift side. It is a perspective view of an automatic reader. It is a perspective view of an automatic reader. It is a perspective view of an automatic reader. It is explanatory drawing of the automatic reader from the other side of a forklift. It is a schematic block diagram of the automatic reading system using a forklift. It is a flowchart of reading of an automatic reading device. It is explanatory drawing of the relationship between the position from the antenna of a tag, and radio wave receiving intensity. It is a graph explaining the state of RSSI before correction | amendment. It is a graph explaining the state of RSSI after correction. It is explanatory drawing that draws one mountain-shaped graph in time series by the radio wave reception signal strength by the radio wave radiation characteristic of an antenna. It is explanatory drawing of the relationship between received signal strength and time. It is explanatory drawing that draws a several mountain-shaped graph in a time series by the radio wave reception signal strength by the radio wave radiation characteristic of an antenna. It is explanatory drawing of the relationship between received signal strength and time. It is explanatory drawing that draws a several mountain-shaped graph in a time series by the radio wave reception signal strength by the radio wave radiation characteristic of an antenna. It is explanatory drawing of the relationship between received signal strength and time.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. It should be noted that members, arrangements, and the like described below do not limit the present invention, and it goes without saying that various modifications can be made in accordance with the spirit of the present invention.
1 to 19 relate to the present invention, FIGS. 1 and 2 are explanatory views of an automatic reading system using an automatic reading device and a forklift, and FIG. 3 is an explanatory view of the automatic reading device with a frame removed. 4 is an explanatory view of the automatic reading device from the forklift side, FIGS. 5 to 7 are perspective views of the automatic reading device, FIG. 8 is an explanatory view of the automatic reading device from the opposite side of the forklift, and FIG. 9 is an automatic using the forklift. 10 is a schematic configuration diagram of the reading system, FIG. 10 is a flowchart of reading by the automatic reading device, FIG. 11 is an explanatory diagram of the relationship between the position of the tag from the antenna and the radio wave reception intensity, and FIG. 12 illustrates the RSSI state before correction. FIG. 13 is a graph illustrating the RSSI state after correction, and FIG. 14 is an explanatory diagram illustrating that the radio wave reception signal strength draws one peak-shaped graph in time series according to the radio wave radiation characteristics of the antenna. 15, 17, and 19 are explanatory diagrams of the relationship between the received signal strength and time, and FIGS. 16 and 18 are graphs in which the received signal strength is a plurality of peaks in time series depending on the radio wave radiation characteristics of the antenna. It is explanatory drawing of.

  The automatic reading device 20 of this embodiment is detachably mounted by a fork 15 of the forklift 10. In general, as shown in FIGS. 1 and 2, the forklift 10 is provided with a driver's seat 12 in the upper part of the machine base 11, and a pair of masts 13 spaced apart from each other stand on the front part of the machine base 11. It is installed. A lift bracket 14 is disposed on the pair of masts 13 so as to move up and down along the mast 13. A pair of forks 15 extending toward the front of the forklift 10 are attached to the front surface of the lift bracket 14 with a gap therebetween. These forks 15 are lifted and lowered along the mast 13 together with the lift bracket 14.

  By driving the forklift 10, the automatic reader 20 described later is powered on. That is, when the ignition key (not shown) provided in the forklift 10 is turned on to drive the forklift, the automatic reader 20 is turned on based on this information.

As shown in FIGS. 1 and 2, the warehouse 40 is an existing one and is provided with shelves corresponding to the height of articles (products). A location tag 41 made of an RF tag is attached to this shelf, and position information indicated by the location tag 41 is obtained. At the same time, product information belonging to the position is linked.
On the other hand, an article (product) stored on the shelf is also attached with a product tag 42 including an RF tag in which product information including its properties and quantity is stored.

The automatic reading device 20 according to the present embodiment includes a base 21, a frame 22, an antenna 23, and a control device 24 as main components.
The base 21 of the present embodiment supports the bottom of the automatic reading device 20 and includes a space 21a into which the fork 15 of the forklift 10 can be inserted. Specifically, as shown in FIG. 3, a box having a hollow rectangular cross section is configured such that a space 21a portion is formed at an interval that allows the two forks 15 of the forklift 10 to enter. . In the present embodiment, the box has a hollow rectangular cross section, but it may be a pallet having a space with a space in which the two forks 15 of the forklift 10 can enter.

  And the frame 22 is integrally arrange | positioned at the upper part of the base 21. FIG. As shown in FIGS. 3 to 8, the frame body 22 of the present embodiment includes a bottom portion 22 a connected to the base 21, an antenna support portion 22 b that extends upward from the bottom portion 22 a and attaches the antenna 23, A frame that reinforces the antenna support portion 22b and attaches the control device, a side frame portion 22d on the front side with respect to the forklift 10, a front outer frame portion 22e, and a frame that covers the driver seat side of the forklift 10 Part 22f. The side frame portion 22d is formed at a distance so as to surround the outside of the antenna 23 on the lower side so as not to block the antenna 23 and to overlap the arrangement surface of the antenna 23, and the outer frame portion 22e. In consideration of reception by the antenna 23, a plurality of rod shapes are formed in a vertical lattice shape.

  The antenna 23 of this embodiment is for reading an RF tag, and is attached to the antenna support portion 22b disposed on the base 21 described above. This attachment is performed at a predetermined interval in a direction intersecting the direction of the space 21a into which the fork 15 of the forklift 10 can be inserted. In the present embodiment, the base 21 is attached in a direction perpendicular to the direction in which the space 21a is formed, and is arranged at predetermined intervals of four in the height direction. Here, the predetermined interval is arranged at a predetermined interval according to the height of the shelf of the existing warehouse 40 to be used. That is, the arrangement interval of the antennas 23 is arranged in accordance with the interval of the shelves of the warehouse 40. This is because the height and width of the shelves differ depending on the articles (commodities) stored in the existing warehouse 40, so the position of the antenna 23 in the height direction can be adjusted. In the present embodiment, the antenna 23 is attached to the antenna support portion 22b so as to be movable in the vertical direction and fixed at a predetermined position.

  The control device 24 of the present embodiment has means for transmitting information acquired by the antenna 23, and includes a CPU 24a and a memory (ROM, RAM, HDD, etc.) 24b. The program stored in the memory 24b is stored in the program stored in the memory 24b. Based on this, the reading range of the RF tag is controlled by the CPU 24a according to the transmission output or the radiation gain, radiation characteristic, and mounting direction of the antenna 23.

  More specifically, the control device 24 includes an RF tag reader 24c, a storage device (memory) 24b and a Wi-Fi (registered trademark) 24d connected to the reader 24c, and a Wi-Fi (registered trademark) 24d. Are connected to the battery 26 via an inverter 24h, an I / O box 24g serving as an I / O (output / input) means, and an inverter 24h. Reference numeral 28 denotes a battery charger.

  The I / O box 24g is connected to the optical sensor 27. The optical sensor 27 detects the presence or absence of an article (product) to be linked to the position information indicated by the location tag 41, and the article (to be linked) ( It is possible to detect a state where there is no (product). Although the optical sensor 27 is provided in the vicinity of the antenna 23 in the present embodiment, the present invention is not limited to this, and the optical sensor 27 can detect (non-detect) an article (product) associated with the position information. If possible, it can be attached to a predetermined position of the automatic reading device 20. Then, management is performed with an external computer device 29 via Wi-Fi (registered trademark) 30... Connected via a LAN.

The control device 24 of the present embodiment compares the RSSI by the antenna 23 and controls to identify the RF tag to be read and other non-target read RF tags.
Further, the control device 24 of the present embodiment controls the forklift 10 to identify only the desired tag without recognizing other overread surrounding tags by passing in front of the RF tag.
Furthermore, the control device 24 of the present embodiment uses a graph in which the radio wave reception signal intensity is a time series in the radio wave radiation characteristics of the antenna 23, and the target RF tags can be connected to each other depending on the magnitude of the time difference between the peak generation times. Control to recognize relative distance.

  When the RF tag attached to the forklift 10 which is a moving means having the antenna 23 or the article (product) is moved, the control device 24 of the present embodiment has the radio wave reception intensity chronologically by reflection of radio waves. The change is detected, and control is performed so as to recognize the movement and stillness of the RF tag attached to the forklift 10 or the article (product).

  The forklift 10 which is a moving means having the reading antenna 23 uses a shelf number tag (specific reading of a shelf is easy to read) using the fact that the radio wave reception signal strength draws a time-series mountain-shaped graph according to the radio wave radiation characteristics of the antenna 23. Crossing the front of the tag), the return signal strength (RSSI) of the shelf number tag is used as a reference value to facilitate identification of other non-target read tags and desired read tags, Control is performed so that only the desired tag is identified without recognizing the surrounding tag which is the target reading tag.

Further, the control device 24 reads the shelf number tag attached to a specific easy-to-read position on the shelf of the existing warehouse 40, thereby controlling the position on the plane of the forklift 10 and the position of the vertical surface of the forklift 10. To do.
That is, using the RFID technology which is an automatic recognition technology, the automatic reading device 20 has one or a plurality of antennas 23 arranged in a three-dimensional manner. In the case of a plurality of antennas 23, these antennas 23 are: It is time-division driven at high speed. In addition, it has a function that can be moved by a forklift 10 (in some cases, manual movement or some driving means such as a conveyor system) at a reading place, and automatically reads an RF tag to be read while moving. .

  Data read by the automatic reading device 20 is stored in a memory 24b in the automatic reading device 20. The data is transferred to a host system such as a data server through a wireless line / optical line. The read product information, location information, linked product information (including presence / absence) and location information are transferred in real time.

  Here, the reader 24c searches for the RF tag and reads the tag information by transmitting and receiving radio waves to and from the RF tag existing around the reader 24c. For this reason, the antenna 23 has a variable function capable of changing the transmission radio wave intensity or the reception radio wave sensitivity stepwise.

  Each article (product) is attached with an RF tag that stores a product code or the like for identifying the product. In addition, RF tags are attached to predetermined positions (such as corners) of the shelf in order to specify the shelf position and the position range of each shelf. Here, RF tags are respectively arranged in predetermined parts (for example, corners) constituting one shelf (three-dimensional rectangular parallelepiped region), and the position range of the shelf is specified by the RF tag. Yes. In the three-dimensional rectangular parallelepiped region of the shelf, the depth direction (vertical direction) of the shelf is associated with the X axis direction, the lateral direction of the shelf is associated with the Y axis direction, and the height direction of the shelf is associated with the Z axis direction. Yes.

  Generally, the inventory data includes items such as “inventory date / time”, “reader coordinate X”, “reader coordinate Y”, “reader coordinate Z”, “tag direction”, “tag distance”, and “tag ID”. Are known, and the control device 24 of the present invention also uses them. “Inventory date / time” indicates the date / time when the reader 24c collected the inventory data, and “leader coordinate X”, “leader coordinate Y”, and “leader coordinate Z” indicate the current 3 of the reader 24c when the inventory data was collected. The position data of the dimension coordinate is shown.

  The “tag direction” indicates a search direction when the reader 24c having a narrow directional antenna searches for an RF tag attached to a product or a shelf. The “tag distance” is the relative distance to the RF tag when the transmission radio wave intensity or reception radio wave sensitivity transmitted from the reader 24c is changed stepwise. In this case, if the radio wave reception signal strength described later draws a mountain-shaped graph in time series according to the radio wave radiation characteristics of the antenna, and a correspondence table of transmission radio wave intensity / reception radio wave sensitivity and distance data is provided, The tag distance can be obtained by referring to this correspondence table. “Tag ID” is tag identification information read from the RF tag, and has a 10-digit configuration as a whole. Code identifier (2 digits) + product code or shelf code (4 digits) + individual ID (4 digits) It becomes the composition of. That is, the upper two digits of the “tag ID” are information read from the RF tag attached to the product when the value is “01” in the product / shelf identification unit. "Indicates information read from the RF tag attached to the shelf. The third to sixth digits of the “tag ID” indicate a product code or shelf code identification unit, and the last four digits are individual ID identification units, that is, individual identification information for identifying individual products or shelves. is there.

In this case, every time the tag ID is read by the reader 24c, the tag ID read this time is additionally stored in the inventory data on condition that the same tag ID is not already stored in the inventory data.
In general, the product position data includes items of “product code”, “individual ID”, “product coordinate X”, “product coordinate Y”, and “product coordinate Z”, and the control device 24 of the present invention. Even use these.

The “product code” is a product code extracted from the “tag ID” when the upper two digits of the “tag ID” read from the RF tag is “01”, and the “individual ID” This is individual identification information for identification. “Product coordinates X”, “Product coordinates Y”, and “Product coordinates Z” are “Reader coordinate X”, “Reader coordinates Y”, “Reader coordinates Z”, “Tag direction”, “Tag distance” corresponding to the product. ”Indicates the location (actual position) of the product calculated based on“ ”.
As the shelf position data, each item of “shelf code”, “individual ID”, “product coordinates X”, “product coordinates Y”, and “product coordinates Z” is known, and the control device 24 of the present invention also includes these items. Is used.

  The “shelf code” is a shelf code extracted from the “tag ID” when the upper two digits of the “tag ID” read from the RF tag is “02”, and the “individual ID” This is individual identification information for identification. “Product coordinates X”, “Product coordinates Y”, and “Product coordinates Z” are “Reader coordinates X”, “Reader coordinates Y”, “Reader coordinates Z”, “Tag direction”, “Tag distance” corresponding to the shelf. The position of the shelf (actual position) calculated based on

  The shelf position range data is three-dimensional coordinate data for specifying each shelf position range for each shelf, and includes “shelf code”, “shelf coordinate range X lower limit”, “shelf coordinate range X upper limit”, and “shelf coordinate”. Each item of “range Y lower limit”, “shelf coordinate range Y upper limit”, “shelf coordinate range Z lower limit”, and “shelf coordinate range Z upper limit” is known, and the control device 24 of the present invention also uses these items. Yes. Product inventory data is data indicating the inventory status by shelf and product calculated based on product location data and shelf location data. Each item of “shelf code”, “product code”, and “stock quantity” is known. These are also used by the control device 24 of the present invention.

The automatic reading device 20 has a three-dimensional shape, and a person who controls the automatic reading device 20 can also be on board. Also, when power from a commercial power source cannot be expected, the operation is timed even when the battery is not connected to the power source.
Further, as described above, the position information indicated by the location tag 41 and the product information belonging to the position are associated with each other.

  As described above, the present invention is suitable for inventory management. By moving the automatic reader 20 having the antenna support portion 22b of the frame 22 up and down with the forklift 10, The TAG (Location Tag and Case Tag) attached to the article (product), that is, the location tag 41 and the product tag 42 can be collectively read, and inventory can be easily grasped in a short time. In particular, since the antennas 23 are arranged on the left and right sides of the automatic reading device 20, when the antenna 23 is on the front surface as in the prior art, the forklift 10 needs to face in that direction. By arranging 23, it becomes possible to read RF tags of pallets and articles (goods) on both sides through which the forklift 10 passes at once, and for picking up and reading the pallets and goods (goods) individually for transportation, Their uses are completely different. If the antenna is on the front as in the past, it is impossible to read many RF tags in a short time. However, if the antenna is on the side as in the present invention, the antenna is connected at a very high speed. A wide range of tags can be read.

  By moving the forklift 10 which is a moving body along a shelf passage of a high-rise / three-dimensional warehouse or an automatic warehouse, it is affixed to an object placed on a shelf on both sides of the passage through which the forklift in the warehouse 40 passes. The RF tag is read using the automatic reading device 20. At the same time, the location tag 41 indicating position information such as a shelf number can be read and managed using the UHF band or RFID.

Further, by mounting the automatic reading device 20 on the fork 15 of the forklift 10 and driving the forklift 10, an automatic reading system that reads the location tag 41 and the product tag 42 made of RF tags can be constructed.
First, the forklift 10 is driven by inserting an ignition key (not shown) of the forklift 10. Thereby, information (forklift drive information) indicating that the ignition key has been inserted is transmitted from the forklift 10 to a control means (CPU) (not shown) connected to the automatic reading device 20. When this control means receives forklift drive information from the forklift 10, it sends a power-on signal to turn on a power supply (not shown) connected to the automatic reader 20, and the automatic reader 20 is turned on. The

Thereafter, based on the data stored in the memory 24b in the control device 24 provided in the automatic reading device 20, the CPU 24a sends a signal (travel signal) for traveling in the warehouse 40 to the control means (not used) provided in the forklift 10. (Shown).
Based on this traveling signal, the forklift 10 travels between the shelves of the warehouse 40 in which articles are stored. At this time, the product tag 42 affixed to the article and the location tag 41 affixed to the shelf are read by the antenna 23 and the product information and the position information are stored in the memory 24 b in the control device 24 by the above configuration.

  At this time, when the forklift 10 travels at a speed of about 6 to 8 km / h, the automatic reading device 20 is moved in a plane, and when the forklift 10 is lifted up, the automatic reading device 20 is moved in the vertical direction. .

  The product information and position information read by the reader 24c connected to the antenna 23 are transmitted to the outside from the output antenna 24e via the reader 24c and Wi-Fi (registered trademark) 24d.

  As described above, the automatic reading system using the forklift 10 according to the present invention can read the location tag 41 and the product tag 42 on the left and right and top and bottom of the shelf of the warehouse 40. Therefore, by automatically running the forklift 10, it is possible to read a package with an IC tag stored in a high-rise, multi-level warehouse such as a three-dimensional warehouse or an automatic warehouse at once, and it is possible to easily manage products. .

Next, control is demonstrated using the flowchart shown in FIG.
Step S1 is an all-antenna time-division reading loop. In this step S1, radio waves are transmitted in order from all antennas connected to the reading device 24 in order of time to acquire tag information. When the process of step S1 ends, the process of step S2 is performed. The processing of step S2 is to hold information on the reading antenna / tag code / received signal strength / sensor response in time series in memory, and adds the acquisition time information to the tag information and holds it in the memory.

  After performing the process of step S2, the process of step S3 is performed. The process in step S3 is a process for moving means stop determination execution / stopping data exclusion process. The data in the memory is scanned to determine the moving apparatus stop determination. If it is determined that the mobile device is stopped, the data for that period is excluded, and then the process proceeds to the determination in step S4.

  Step S4 determines whether or not the received signal strength time series graph has drawn a mountain. More specifically, the data in the memory from which the data in the mobile device stop period is excluded is scanned to obtain the received signal strength. A series graph is drawn for each tag and antenna. As a result, when there is a mountain-shaped tag (S4: Yes), the process proceeds to step S5, and when it does not exist (S4: No), the process returns to step S1, and the processes of steps S1 to S4 are performed.

  In step S5, it is determined whether or not there is a deviation in the peak / peak occurrence time of the location / product tag. More specifically, the deviation in the peak / peak occurrence time of the location tag 41 and the product tag 42 is small. In (S5: No), it is determined that there is a product on the location, and the process of step S7 is performed. That is, in step S7, location and product tag information is transmitted to the upper server (with association), and the tag information is associated and transmitted to the upper server. Then, it returns to step S1 and performs the process of step S1 to S5.

  On the other hand, when the deviation of the peak apex time is large, or when the tag depicting the peak is only the location tag 41 (S5: Yes), it is determined that there is no product on the location, and the process of step S6 is performed. Do. That is, in step S6, only the location tag information is transmitted (not linked) to the upper server, and only the location tag information is transmitted to the upper server. Then, it returns to step S1 and performs the process of step S1 to S5.

  In the present invention, using the position of the tag from the antenna and the radio wave reception intensity (RSSI), it is utilized that the time series graph of the reception signal intensity draws a mountain due to the movement of the forklift as a mobile device or the tag, Both the main and secondary poles of radiation can be used. Further, when the sub-pole is asymmetrical, the moving direction can be detected based on its size and number.

  More specifically, the position of the RF tag from the antenna and the radio wave reception intensity (RSSI) vary depending on the distance as shown in FIG. For example, the RSSI is high in the range of 60 ° from the antenna, but the RSSI is low outside this range. Also, it varies depending on the distance. For example, during a long-distance movement or stationary period, the radio wave reception intensity (RSSI) does not draw a mountain.

  For this reason, the part which does not draw a mountain, for example, the data for the X period shown in FIG. 12 (data of the stationary period) is deleted, and the state as shown in FIG.

For example, FIG. 14 is an explanatory diagram of drawing one peak-shaped graph in time series according to the radio wave radiation characteristics of the antenna, and the direction of the forklift as a moving means, the RF tag, and the radio wave The radiation characteristics will be described. In such radio wave radiation characteristics, the received signal intensity and time have a relationship as shown in FIG.
FIG. 16 is an explanatory diagram of drawing a plurality of mountain-shaped (main pole and sub pole) graphs of the radio wave reception signal intensity in time series according to the radio wave radiation characteristics of the antenna. The RF tag and the radio wave radiation characteristics will be described. In such radio wave radiation characteristics, the received signal intensity and the time have a relationship as shown in FIG.
Further, FIG. 18 is an explanatory diagram for drawing a graph of a plurality of mountain shapes (in the case of a main pole and a sub pole and a magnitude of the sub music) in time series according to the radio wave radiation characteristics of the antenna. There will be described a moving direction of a forklift as a moving means, an RF tag, and radio wave radiation characteristics. In such radio wave radiation characteristics, the received signal intensity and time have a relationship as shown in FIG.

  Utilizing the fact that the radio wave reception signal strength as described above draws a mountain-shaped graph in time series according to the radio wave radiation characteristics of the antenna, (1) the mobile device having the reading antenna crosses in front of the tag and other Identifying only the desired tag without recognizing the overreading surrounding tag; (2) identifying only the desired tag without recognizing other overreading surrounding tags by passing the tag in front of the reading antenna; 3) Recognizing the speed of the moving device and tag, (4) Recognizing the relative distance between the target tags based on the difference in peak peak generation time, and (5) Moving the moving device and tag, and their direction and speed. (6) It is possible to recognize that the mobile device or the tag has moved or stopped.

The present invention includes the following aspects. That is,
(1) Utilizing the fact that the radio wave reception signal strength draws one or a plurality of mountain-shaped graphs in time series according to the radio wave radiation characteristics of the antenna, and others when the mobile device having the reading antenna crosses in front of the tag The reader (system) has a function of recognizing only the desired tag without recognizing the over-reading surrounding tag.
(2) Utilizing the fact that the radio wave reception signal strength draws one or more mountain-shaped graphs in time series according to the radio wave radiation characteristics of the antenna, and other overreading surrounding tags by crossing the front of the reading antenna A reader (system) having a function of identifying only a desired tag without recognition.
(3) Reading device (system) having a function of recognizing the speed of a mobile device or a tag by drawing one or a plurality of mountain graphs in time series according to the radio wave radiation characteristics of the antenna. .
(4) A reading apparatus having a function of recognizing the relative distance between target tags based on the magnitude of the time difference between peak apex occurrences, using the fact that the radio wave reception signal strength draws a mountain-shaped graph in time series according to the radio wave radiation characteristics of the antenna. (system).
(5) By using an antenna having radio wave radiation characteristics consisting of a main pole and a plurality of left and right asymmetric sub-poles, it is possible to utilize that the time-series received signal strength graphs draw a plurality of differently shaped peaks. A reading device (system) having a function of identifying movement of a moving device or a tag and its direction and speed.
(6) When the mobile device or tag having an antenna moves, the fact that the radio wave reception intensity changes in time series due to the reflection of the radio wave, etc. is used to recognize that the mobile device or tag has moved or is stationary. Reader (system) having a function to perform.

10 forklift 11 machine base 12 driver's seat 13 mast 14 lift bracket 15 fork 20 automatic reader 21 base 22 frame 21a space 22a bottom 22b antenna support 22c support frame 22d side frame 22e outer frame 22f frame body 23 Antenna 24 Controller 24a CPU
24b Memory 24c Reader 24d, 30 Wi-Fi (registered trademark)
24e I / O antenna 24f AC adapter 24g I / O box 24h Inverter 26 Battery 27 Optical sensor 28 Battery charger 29 Computer device 40 Warehouse 41 Location tag (RF tag)
42 Product tag (RF tag)

Claims (9)

An automatic reading device that reads information on RF tags of articles stored in a warehouse and collects information, and is provided with a base having a space in which a fork of a forklift can be inserted, and disposed on the base Acquired with a frame, an RF tag reading antenna disposed at a predetermined interval at least in the height direction in a direction intersecting the direction of the space in which the fork of the frame can be inserted, and the antenna A control device having means for transmitting the received information,
The automatic reading device is characterized in that the antennas are arranged at intervals in accordance with the intervals of warehouse shelves.   2. The automatic reading device according to claim 1, wherein the control device controls a reading range of the RF tag according to a transmission output or a radiation gain, a radiation characteristic, and a mounting direction of the antenna.   The automatic reading device according to claim 1 or 2, wherein the control device compares an RSSI by the antenna and identifies an RF tag to be read and another non-target reading RF tag.   4. The control device according to claim 1, wherein the forklift identifies only a desired tag without recognizing other overread surrounding tags when the forklift passes in front of the RF tag. 5. The automatic reader described in 1.   The control device recognizes the relative distance between the target RF tags based on the magnitude of the time difference between the peak generation times by using a graph in which the radio wave reception signal intensity is drawn in time series in the radio wave radiation characteristics of the antenna. The automatic reading device according to any one of claims 1 to 4.   When a moving means or tag having an antenna moves, it detects that the radio wave reception intensity changes in time series due to radio wave reflection or the like, and recognizes the movement or stationary of the forklift or the RF tag. 6. The automatic reading device according to claim 1, wherein   Utilizing the fact that the radio wave reception signal strength draws a mountain-shaped graph in time series according to the radio wave radiation characteristics of the antenna, the moving means having the antenna for reading is attached to a shelf number tag (a specific easy-to-read position on the shelf). )), The return signal strength (RSSI) of the shelf number tag is used as a reference value to facilitate identification of other non-target read tags and desired read tags, and other non-target read tags. 7. The automatic reading apparatus according to claim 1, wherein a desired tag is identified without recognizing a certain surrounding tag.   The system has a function of identifying a position on a plane of the forklift and a position of a vertical surface of the forklift by reading the shelf number tag attached to a specific easy-to-read position on a shelf in a warehouse. Item 8. The automatic reading device according to any one of Items 1 to 7. An automatic reading system that reads an RF tag by mounting the automatic reading device according to claim 1 on a fork of a forklift and driving the forklift,
By driving the forklift, the automatic reading device is turned on and travels between shelves in a warehouse that stores articles by the forklift, and reads and reads the RF tags provided on the articles and the shelves by the antenna. Information is stored and sent to the outside.
Automatic movement using a forklift that makes it possible to read RF tags on the left, right, and top and bottom of a warehouse shelf by moving in the plane by running the forklift and moving in the vertical direction by lifting the forklift. Reading system.