Wireless tag reading device

Abstract

A wireless tag reading device of an embodiment that is for reading tag information of a wireless tag attached to an article housed in a housing portion, including: a bottom surface portion; and a plurality of side surface portions erected upward from an end of the bottom surface portion, the housing portion being surrounded by the bottom surface portion and the side surface portions, in which the wireless tag reading device includes: inside the side surface portions, an antenna that radiates a radio wave into the housing portion; a radio wave reflecting unit that is provided outside the antenna and that reflects the radio wave radiated from the antenna toward the housing portion; and a radio wave absorbing unit that is provided at an upper portion of the radio wave reflecting unit and that absorbs the radio wave radiated from the antenna. Figure 2.

Description

Wireless tag reader

[0001] An embodiment of the present invention relates to a radio tag reader.

[0002] Recently, in supermarkets, mass retailers, and other stores, wireless tag readers have been installed that attach wireless tags to items such as merchandise sold in the store and read information related to the items from the wireless tags. The items are placed in a basket, for example, and brought to a checkout booth. The wireless tag reader installed at the checkout booth uses an antenna to read all the items in the basket at once and perform payment processing for the items to be purchased.

[0003] The RFID tag reader is a box-shaped device with an opening at the top, front, or both, and a hollow storage compartment inside. A customer or a store clerk places an item or a basket containing items inside the box through the opening. The RFID tag reader emits radio waves from an antenna installed on the bottom or side of the box to the storage compartment inside the box, and reads information from the wireless tags attached to the items placed in the storage compartment.

[0004] Incidentally, wireless tag readers often include a radio wave reflector to prevent radio waves emitted from the antenna from leaking outside. The radio wave reflector reflects radio waves leaking outside toward the storage unit. In the storage unit, radio waves emitted from the antenna and radio waves reflected by the radio wave reflector are mixed. In this state, radio waves may interfere with each other, resulting in a null point where the radio waves are weak. Because radio waves from the antenna have difficulty reaching a wireless tag located at a null point, it may be difficult to read the tag information of the wireless tag.

[0005] An object of the present invention is to provide a radio tag reader that can improve the accuracy of reading tag information from a radio tag.

[0006] The radio tag reading device of the embodiment has a bottom portion and a plurality of side portions standing upward from the end of the bottom portion, and is a radio tag reading device that reads tag information of a radio tag attached to an item stored in a storage section surrounded by the bottom portion and the side portions, and is equipped with an antenna inside the side portion that radiates radio waves to the radio tag, a radio wave reflecting portion that is provided outside the antenna and reflects the radio waves radiated from the antenna toward the storage section, and a radio wave absorbing portion that is provided above the radio wave reflecting portion and absorbs the radio waves radiated from the antenna.

[0007] Fig. 1 is a perspective view showing a wireless tag reading device according to an embodiment, Fig. 2 is an explanatory cross-sectional view of the wireless tag reading device taken along line A-A, and Fig. 3 is a block diagram showing the hardware configuration of the wireless tag reading device.

[0008] Hereinafter, an embodiment will be described with reference to the drawings. In the embodiment, a product sold in a store will be described as an example of an article. Furthermore, the present invention is not limited to the embodiment.

[0009] The wireless tag reader 1 is connected to a self-service POS (Point of Sales) terminal where, for example, a customer registers and settles the items they purchase (e.g., clothing or groceries), and reads product information (product name, product price, etc.) wirelessly transmitted from a wireless tag attached to the purchased item. The wireless tag reader 1 transmits the read product information to the self-service POS terminal. The self-service POS terminal executes a payment process for the item purchased by the customer based on the product information received from the wireless tag reader 1.

[0010] Fig. 1 is a perspective view showing a radio tag reader 1 according to an embodiment. The radio tag reader 1 shown in Fig. 1 has a hollow, substantially rectangular parallelepiped or cubic shape. The radio tag reader 1 has a shield portion 11. The shield portion 11 has a bottom surface portion 12, side surfaces 13, and a rear surface portion 14.

[0011] The bottom surface portion 12 has a planar shape located at the bottom of the shield portion 11. The side surface portion 13 has two planar shapes (side surface portion 13A, side surface portion 13B) that stand upward at approximately a right angle from both the left and right sides of the bottom surface portion 12. The side surface portion 13 is integrally formed with the bottom surface portion 12. The rear surface portion 14 is provided at the rear of the wireless tag reading device 1. The rear surface portion 14 has a planar shape that stands upward at approximately a right angle from the rear part of the bottom surface portion 12. The rear surface portion 14 is formed by being fitted from above into a slit (not shown) provided on the rear side of the side surface portion 13. The rear surface portion 14 has the same structure as the side surface portion 13 and is a type of side surface portion 13.

[0012] Such a wireless tag reader 1 has a hollow structure with an opening 24 at the top that opens upward and an opening 25 at the front that opens forward, and an internal storage section 15. A customer or a store clerk places an item to be purchased or a basket K containing items on the bottom section 12, and the item is placed (stored) in the storage section 15. The customer or store clerk holds a handle K1 provided on the top of the basket K and places the basket K on the bottom section 12.

[0013] The storage section 15 is deep and wide enough to store the entire basket K. Therefore, products stored up to the upper position of the basket K fit comfortably within the storage section 15 and do not protrude upward from the storage section 15. Furthermore, products in this state do not protrude upward from the wireless tag reading device 1.

[0014] Furthermore, the product does not necessarily have to be in a basket, and may be placed directly in the storage section 15 .

[0015] The RFID tag reader 1 also has an arm 17 attached to the rear side of the side surface 13A. The arm 17 can freely extend, retract, move, and rotate upward and left and right. A display unit 18 is attached to the tip of the arm 17. The display unit 18 is, for example, a liquid crystal display, and displays information to the person operating the RFID tag reader 1. The display unit 18 displays, for example, product information corresponding to tag information received from a RFID tag as a list of products to purchase. The operation unit 19 is, for example, a touch panel provided on the display unit 18. The operation unit 19 outputs information related to a key displayed on the display unit 18 by operating a position corresponding to the key. The display unit 18 can adjust its display position and direction by extending, retracting, moving, and rotating the arm 17. The display unit 18 is usually installed at the rear of the RFID tag reader 1 (for example, at the top of the rear surface 14).

[0016] Fig. 2 is an explanatory diagram of the RFID tag reader 1, taken along the line A-A in Fig. 1. In Fig. 2, the RFID tag reader 1 has a flat bottom surface 12 and side surfaces 13 extending upward from both ends of the bottom surface 12. In Fig. 2, a side surface 13A extends upward from the right end of the bottom surface 12. In Fig. 2, a side surface 13B extends upward from the left end of the bottom surface 12.

[0017] A plurality of planar antennas 21 are housed (embedded) inside the shield section 11 of the RFID tag reader 1. Specifically, the planar antenna 211 is housed in approximately the center of the bottom section 12. The plane formed on the antenna 211 faces the up-down direction. The planar antenna 212 is housed in approximately the center of the side section 13A. The plane formed on the antenna 212 faces the left-right direction. The planar antenna 213 is housed in approximately the center of the side section 13B. The plane formed on the antenna 212 faces the left-right direction. The antenna 211 mainly radiates radio waves in the up-down direction in FIG. 2 . The antenna 212 mainly radiates radio waves in the left-right direction in FIG. 2 . The antenna 213 mainly radiates radio waves in the left-right direction in FIG. 2 . That is, the antenna 21 radiates radio waves from one surface toward the housing section 15. The antenna 21 radiates radio waves from the other surface toward areas other than the housing section 15.

[0018] Furthermore, a radio wave reflecting portion 22 is housed (embedded) inside the shield portion 11 of the RFID tag reader 1. The radio wave reflecting portion 22 has the property of reflecting radio waves radiated from other surfaces of the antenna 21 and is made of a metal plate such as aluminum. The radio wave reflecting portion 22 is disposed outside the antenna 21. Specifically, a flat radio wave reflecting portion 221 is housed in the bottom portion 12. The radio wave reflecting portion 221 is disposed outside the antenna 211 (lower side in FIG. 2 ). The side portion 13A also houses a flat radio wave reflecting portion 222. The radio wave reflecting portion 222 is disposed outside the antenna 212 (right side in FIG. 2 ). The side portion 13B also houses a flat radio wave reflecting portion 223. The radio wave reflecting portion 223 is disposed outside the antenna 213 (left side in FIG. 2 ).

[0019] The radio wave reflecting portion 221, the radio wave reflecting portion 222, and the radio wave reflecting portion 223 are integrally formed. That is, the radio wave reflecting portion 22 has the radio wave reflecting portion 221, the radio wave reflecting portion 222, and the radio wave reflecting portion 223.

[0020] The radio wave reflecting portion 222 is formed at a substantially right angle to the radio wave reflecting portion 221. The radio wave reflecting portion 223 is formed at a substantially right angle to the radio wave reflecting portion 221. The radio wave reflecting portions 222 and 223 are formed at a substantially parallel angle to each other. That is, the radio wave reflecting portion 22 is formed in a substantially U-shape with an open upper side when the RFID tag reading device 1 is viewed from the front side in FIG. 2 .

[0021] Furthermore, the upper end S of the radio wave reflecting portion 22 extends to a position where it overlaps in the vertical direction with the antennas 212 and 213. Specifically, the upper end S1 of the radio wave reflecting portion 222 extends to a position where it overlaps in the vertical direction with the antenna 212. Furthermore, the upper end S2 of the radio wave reflecting portion 223 extends to a position where it overlaps in the vertical direction with the antenna 213.

[0022] Furthermore, at the upper end S1, a planar radio wave absorbing portion 23 is laminated on the upper end S of the radio wave reflecting portion 22. Specifically, a planar radio wave absorbing portion 231 is laminated on the upper end S1 of the radio wave reflecting portion 222. Here, the vertical length of the radio wave reflecting portion 222 and the vertical length of the radio wave absorbing portion 231 are substantially the same. Furthermore, a planar radio wave absorbing portion 232 is laminated on the upper end S2 of the radio wave reflecting portion 223. Here, the vertical length of the radio wave reflecting portion 223 and the vertical length of the radio wave absorbing portion 232 are substantially the same. The radio wave absorbing portion 23 has the property of absorbing radio waves radiated from the antenna 21 and is formed of a planar plate such as ferrite. The RFID tag reading device 1 prevents radio waves from leaking to the outside by absorbing the radio waves radiated from the antenna 21.

[0023] The antennas 21 (antennas 211, 212, and 213) are connected to a coaxial cable L2 for electrical connection with the control unit 300 (see FIG. 3 ) in order to receive signals from the RFID tag reader 1 in order to emit radio waves and to transmit information received from the RFID tags to the control unit 300 of the RFID tag reader 1. The radio wave reflecting unit 22 is provided with a hole (not shown) through which the coaxial cable L2 passes in order to connect it to the antennas 21.

[0024] The rear surface 14 described above houses a radio wave reflecting portion 22 and a radio wave absorbing portion 23 , and performs the same function as the side surface 13 .

[0025] Furthermore, a strip-shaped LED (Light Emitting Diode) 16 is provided facing upward at the upper end of the side surface portion 13 (side surface portion 13A and side surface portion 13B). The LED 16 conveys various information to the operator by displaying different indication methods (lighting up, flashing, color) to indicate whether or not the reading of a wireless tag by the wireless tag reader 1 is in progress or has been completed.

[0026] In the wireless tag reading device 1 configured as described above, radio waves P1 emitted from the antenna 211 toward the storage section 15 reach the wireless tag attached to the product. The wireless tag transmits tag information as a response wave in response to the received radio waves P1. The antenna 21 receives the tag information from the wireless tag. Furthermore, radio waves P2 emitted from the antenna 211 toward the radio wave reflecting section 221 are reflected by the radio wave reflecting section 221 and reach the wireless tag attached to the product. The wireless tag transmits tag information in response to the received radio waves P2. The antenna 21 receives the tag information from the wireless tag.

[0027] Furthermore, radio waves P1 radiated from the antenna 212 toward the storage section 15 reach the wireless tag attached to the product. The wireless tag transmits tag information in response to the received radio waves P1. The antenna 21 receives the tag information from the wireless tag. Furthermore, radio waves P2 radiated from the antenna 212 toward the radio wave reflecting section 222 are reflected by the radio wave reflecting section 222 and reach the wireless tag attached to the product. The wireless tag transmits tag information in response to the received radio waves P2. The antenna 21 receives the tag information from the wireless tag. Furthermore, radio waves P3 radiated from the antenna 212 toward the radio wave absorbing section 231 are absorbed by the radio wave absorbing section 231.

[0028] Furthermore, radio waves P1 radiated from the antenna 213 toward the storage section 15 reach the wireless tag attached to the product. The wireless tag transmits tag information in response to the received radio waves P1. The antenna 21 receives the tag information from the wireless tag. Furthermore, radio waves P2 radiated from the antenna 213 toward the radio wave reflecting section 223 are reflected by the radio wave reflecting section 223 and reach the wireless tag attached to the product. The wireless tag transmits tag information in response to the received radio waves P2. The antenna 21 receives the tag information from the wireless tag. Furthermore, radio waves P3 radiated from the antenna 213 toward the radio wave absorbing section 232 are absorbed by the radio wave absorbing section 232.

[0029] Since the radio waves P1 and P2 have different phases, interference between the radio waves P1 and P2 can result in null points where the radio wave intensities cancel each other out. A wireless tag located at such a null point may be unable to receive the radio waves emitted by the antenna 21. Null points tend to occur more frequently as the vertical lengths of the radio wave reflecting portion 222 and the radio wave reflecting portion 223 are longer. However, in this embodiment, the vertical lengths of the radio wave reflecting portion 222 and the radio wave reflecting portion 223 are shortened, and the radio wave absorbing portions 231 and 232 are stacked on top of them. Therefore, the radio wave reflecting portion 22 is not present where the radio wave absorbing portions 231 and 232 are stacked, thereby reducing the number of null points. As a result, the reading accuracy of the wireless tag located within the storage portion 15 can be improved. Furthermore, the stacked radio wave absorbing portions 231 and 232 can prevent the radio waves emitted by the antenna 21 from leaking to the outside. Furthermore, since the radio wave reflecting portion 222 and the radio wave reflecting portion 223 are formed of metal, the vertical length of the radio wave reflecting portion 222 and the vertical length of the radio wave reflecting portion 223 are made short, which contributes to reducing the weight of the radio tag reading device 1.

[0030] Next, the hardware configuration of the radio tag reader 1 will be described. FIG. 3 is a block diagram showing the hardware configuration of the radio tag reader 1. As shown in FIG. 3, the radio tag reader 1 includes a CPU (Central Processing Unit) 31, a ROM (Read Only Memory) 32, a RAM (Random Access Memory) 33, a memory unit 34, and the like. The CPU 31 is the main controller. The ROM 32 stores various programs. The RAM 33 loads programs and various data. The memory unit 34 stores various programs. The CPU 31, the ROM 32, the RAM 33, and the memory unit 34 are connected to one another via a bus 35. The CPU 31, the ROM 32, and the RAM 33 constitute a control unit 300. That is, the control unit 300 executes control processing of the radio tag reader 1, which will be described later, by the CPU 31 operating in accordance with a control program stored in the ROM 32 or the memory unit 34 and loaded in the RAM 33.

[0031] The RAM 33 includes a tag information unit 331. The tag information unit 331 stores product information (product code, product name, product price, etc.) of the product purchased by the customer, which is acquired based on the tag information read by the wireless tag reading device 1.

[0032] The memory unit 34 is composed of a solid state drive (SSD), a hard disk drive (HDD), flash memory, etc., and maintains its stored contents even when power is cut off. The memory unit 34 includes a control program unit 341 and a product master 342. The control program unit 341 stores a control program for controlling the wireless tag reading device 1. The product master 342 stores product information for the product in association with an individual product number that identifies the product, or a product code for the product that includes the individual product number.

[0033] The control unit 300 is connected to an R / W (reader / writer) 38, LED 16, display unit 18, and operation unit 19 via a bus 35 and a controller 36. The display unit 18 is, for example, a liquid crystal display. The operation unit 19 is, for example, a touch panel. The R / W 38 is connected to an antenna 21 (antenna 211, antenna 212, antenna 213) via a communication line L2. The R / W 38 generates radio waves to be radiated from the antenna 21 based on information for reading wireless tags created by the control unit 300 and transmits the radio waves to the antenna 21. The R / W 38 also converts tag information received by the antenna 21 in the form of radio waves into tag information that can be analyzed by the control unit 300.

[0034] The control unit 300 is also connected to a communication unit 37 via a bus 35. The communication unit 37 is electrically connected to a self-service POS terminal via a connection line L, and is capable of transmitting and receiving information to and from the self-service POS terminal.

[0035] When the control unit 300 of the wireless tag reading device 1 detects that a basket K has been placed in the storage unit 15, it emits radio waves from the antenna 21 and receives tag information, including information identifying the product as an individual item, from the wireless tags attached to the products stored in the basket K placed in the storage unit 15. The control unit 300 then searches the product master 342 based on the tag information, obtains product information for the corresponding product, and stores it in the tag information unit 331. The control unit 300 also displays the obtained product information on the display unit 18. When the control unit 300 has finished reading the wireless tag, it lights or blinks the LED 16 to notify the operator of the reading status (for example, whether reading is in progress or has finished).

[0036] As described above, the radio tag reading device 1 in the embodiment has a bottom portion 12 and a plurality of side portions 13 extending upward from the end of the bottom portion 12, and is a radio tag reading device 1 that reads tag information of a radio tag attached to a product stored in a storage section 15 surrounded by the bottom portion 12 and the side portions 13. Inside the side portion 13, it is equipped with an antenna 21 that radiates radio waves to the radio tag, a radio wave reflecting portion 22 that is provided outside the antenna 21 and reflects the radio waves radiated from the antenna 21 toward the storage section 15, and a radio wave absorbing portion 23 that is stacked on the upper portion S of the radio wave reflecting portion 22 and absorbs the radio waves radiated from the antenna 21.

[0037] In the RFID tag reader 1 of this embodiment, the vertical length of the radio wave reflecting section 22 is shortened and the radio wave absorbing section 23 is laminated on top of it. Therefore, the radio wave reflecting section 22 is not present where the radio wave absorbing section 23 is laminated, and radio waves are not reflected at this position, so the number of points where null points occur within the storage section 15 can be reduced. As a result, the reading accuracy of the RFID tag located within the storage section 15 can be improved. In addition, the laminated radio wave absorbing section 23 can prevent radio waves radiated by the antenna 21 from leaking from the RFID tag reader 1 to the outside.

[0038] Although an embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. This embodiment can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. This embodiment and its modifications are included within the scope and spirit of the invention, and are also included in the inventions described in the claims and their equivalents.

[0039] For example, in the embodiment, a detachable rear surface portion 14 is provided. However, the rear surface portion 14 may be fixedly provided to the radio tag reading device 1. Conversely, the radio tag reading device 1 may not be provided with the rear surface portion 14. Also, a side surface portion 13 having a similar configuration to the rear surface portion 14 may be provided on the front surface opposite the rear surface portion 14. In this case, the side surface portion 13 provided on the front surface may be detachable from the radio tag reading device 1 or may be fixed to the radio tag reading device 1.

[0040] In addition, in the embodiment, a product is used as an example of the product, but the product is not limited to this and may be something other than a product.

[0041] Japanese Patent Application Laid-Open No. 2018-190255

Claims

1. A radio tag reading device that has a bottom portion and multiple side portions standing upright from the end of the bottom portion and that reads tag information of a radio tag attached to an item stored in a storage portion surrounded by the bottom portion and the side portions, wherein the radio tag reading device is equipped with, inside the side portions, an antenna that radiates radio waves to the radio tag, a radio wave reflecting portion that is provided outside the antenna and reflects the radio waves radiated from the antenna toward the storage portion, and a radio wave absorbing portion that is provided above the radio wave reflecting portion and absorbs the radio waves radiated from the antenna.

2. The RFID tag reader according to claim 1, wherein the antenna and the radio wave reflecting portion are also provided on the bottom surface below the antenna.

3. The radio tag reader according to claim 1 or 2, wherein an opening is provided on the top surface of the radio tag reader.

4. The radio tag reader according to claim 1 or 2, wherein openings are provided on the top and front surfaces of the radio tag reader.

5. The radio tag reader according to any one of claims 1 to 4, wherein the side portion provided on the rear surface of the radio tag reader is detachable.