reader

Abstract

To provide a reader capable of efficiently and reliably reading an RFID tag.SOLUTION: A reader has a detected section, a basket stand, an antenna, a detection section, moving means, and suppression means. The detected section is mounted to an outer peripheral section of a shopping basket for putting in a commodity having an RFID tag. The basket stand is a stand for placing the shopping basket. The antenna is disposed under the basket stand, and radiates electric waves communicating with an RFID tag of a commodity in the shopping basket placed on the basket stand. The detection section is disposed under the basket stand, and detects the detected section mounted to the shopping basket placed on the basket stand. The moving means moves a movable body for fixing the antenna and the detection section along the basket stand. The suppression means suppresses electric waves radiated to the outside of the shopping basket when the detection section of the movable body that travels in a state in which the antenna is disposed in an opposing area that opposes the shopping basket detects the detected section.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a reader that reads an RFID tag attached to, for example, a product. [Background technology]

[0002] The reader that reads the RFID tags on products is equipped with an antenna that emits radio waves to communicate with the RFID tag under the frame (loading area) where the shopping cart is placed on the counter. To prevent problems that reduce reading accuracy due to the orientation of the product (RFID tag) or its position in the basket, some readers have an antenna that can be moved within the loading area.

[0003] When the antenna is moved within the mounting area, there is a possibility that it may erroneously read an RFID tag outside the mounting area when it reaches the edge of the mounting area. For this reason, a technology is known that detects when the antenna has reached the edge of the mounting area and weakens the strength of the radio waves emitted from the antenna. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-49840 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, with the conventional reading device described above, if the shopping cart is placed slightly off the placement area, there is a possibility that the RFID tags of the products that extend beyond the placement area will not be read.

[0006] Furthermore, in the conventional reading device described above, when a shopping basket smaller than normal is placed in the placement area, the antenna is unnecessarily moved to an area that exceeds the size of the shopping basket, resulting in poor reading efficiency.

[0007] The problem to be solved by the embodiments of the present invention is to provide a reader that can read RFID tags efficiently and reliably. [Means for solving the problem]

[0008] A reading device according to one embodiment includes a detected part, a basket stand, an antenna, a detecting part, a moving means, and a suppressing means. The detected part is attached to the outer periphery of a shopping basket containing products with RFID tags. The basket stand is a stand on which the shopping basket is placed. The antenna is disposed under the basket stand and emits radio waves that communicate with the RFID tags of products in the shopping basket placed on the basket stand. The detecting part is disposed under the basket stand and detects the detected part attached to the shopping basket placed on the basket stand. The moving means moves a movable body to which the antenna and detecting part are fixed along the basket stand. The suppressing means suppresses radio waves emitted outside the shopping basket when the detecting part of the movable body, which is moving with its antenna disposed in an opposing area facing the shopping basket, detects the detected part. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view showing a reading device according to the first embodiment. [Figure 2] FIG. 2 is a schematic diagram showing the structure under the top plate of the reading device of FIG. [Figure 3] FIG. 3 is a perspective view of the shopping basket of FIG. 1 with a magnet attached to the bottom. [Figure 4] FIG. 4 is a block diagram showing the configuration of the reading device of FIG. [Figure 5] FIG. 5 is a diagram for explaining the operation of the reading device of FIG. [Figure 6] FIG. 6 is a diagram for explaining the operation of the reading device of FIG. [Figure 7] FIG. 7 is a diagram for explaining the operation of the reading device of FIG. [Figure 8] FIG. 8 is a schematic diagram showing the main parts of a reading device according to the second embodiment. [Figure 9] FIG. 9 is a perspective view of a shopping basket to be placed on the placement surface of the reading device of FIG. [Figure 10] FIG. 10 is a diagram for explaining the operation of the reading device of FIG. [Figure 11] FIG. 11 is a diagram for explaining the operation of the reading device of FIG. [Figure 12] FIG. 12 is a diagram for explaining the operation of the reading device of FIG. [Figure 13] FIG. 13 is a diagram for explaining the operation of the reading device of FIG. [Figure 14] FIG. 14 is a diagram for explaining the operation of the reading device of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments will be described with reference to the drawings. As shown in Fig. 1, a reading device 10 according to the first embodiment has a housing 1 equipped with a substantially rectangular top panel 2. The top panel 2 has a horizontal mounting surface 3 on which a shopping basket 20 containing products 22 with RFID tags 21 attached thereto is placed. The top panel 2 functions as a basket stand. The top panel 2 is made of a material that allows radio waves to pass through for communication with the RFID tags 21.

[0011] The reading device 10 is installed, for example, at a checkout counter next to a POS (Point Of Sales) terminal 100 (FIG. 4) that registers and settles purchases. While FIG. 1 shows an example in which two reading devices 10 are installed side by side, it is sufficient for the checkout counter to have at least one reading device 10.

[0012] In the following description, the direction in which the two reading devices 10 are lined up is referred to as the left-right direction, the direction parallel to the placement surface 3 and perpendicular to the left-right direction is referred to as the front-rear direction, and the vertical direction perpendicular to both the left-right direction and the front-rear direction is referred to as the up-down direction. In each drawing, the direction from left to right is indicated by arrow X, the direction from back to front is indicated by arrow Y, and the direction from bottom to top is indicated by arrow Z.

[0013] FIG. 2 is a perspective view of the reading device 10 with the top panel 2 removed. The reading device 10 is provided with a movable body 6 under the top panel 2, to which an antenna 4 and a magnetic sensor 5 are integrally fixed. The antenna 4 emits radio waves to communicate with an RFID tag 21 attached to an item 22 in a shopping basket 20 placed on the placing surface 3 of the top panel 2. The magnetic sensor 5 detects magnetism emitted by magnets 23, 24 (FIG. 3) attached to the shopping basket 20 placed on the placing surface 3. The magnetic sensor 5 is an example of a detection unit.

[0014] As shown in Figure 3, shopping basket 20 has two magnets 23, 24 on the outer periphery of its bottom 25. Bottom 25 of shopping basket 20 is roughly rectangular, with magnets 23, 24 provided in the centers of the short sides at both ends in the longitudinal direction. Magnets 23, 24 are attached to shopping basket 20 with, for example, adhesive. Magnets 23, 24 are an example of a detectable part. Shopping basket 20 is placed on placement surface 3 with its longitudinal direction oriented along the front-to-rear direction.

[0015] The magnets 23, 24 do not necessarily have to be provided on the bottom 25 of the shopping basket 20. The magnets 23, 24 may be attached to the outer periphery of the shopping basket 20. The outer periphery of the shopping basket 20 includes, for example, a cylindrical peripheral portion 26 extending upward from each side of the bottom 25. The magnets 23, 24 may also be attached to the peripheral portion 26 closer to the bottom 25. In order to enable the magnetic sensor 5 disposed below the placing surface 3 to efficiently detect the magnetism emitted by the magnets 23, 24, it is desirable to attach the magnets 23, 24 to the bottom 25 of the shopping basket 20 closer to the placing surface 3.

[0016] As shown in FIG. 4, the reading device 10 includes a control unit 30, a moving mechanism 40, a reader / writer 50, and a communication I / F 60.

[0017] The movement mechanism 40 moves and stops the movable body 6 in the front-rear direction along rails 7 (FIG. 2) that extend in the front-rear direction under the top board 2. The movement mechanism 40 has an actuator 41 that moves the movable body 6 and a motor 42 that drives the actuator 41. The actuator 41 may be, for example, a ball screw in which a nut fixed to the movable body 6 is screwed onto a screw shaft. In this case, the motor 42 is connected to one end of the screw shaft via a coupling. The movement mechanism 40 is an example of a movement means.

[0018] The reader / writer 50 emits radio waves via the antenna 4, and by communicating with the RFID tags, receives information about the purchased items (product information) via the antenna 4, and reads the product information of all the items 22 in the shopping cart 20. The product information includes, for example, the product name and price.

[0019] The control unit 30 transmits the product information read by the reader / writer 50 to the POS terminal 100 via the communication I / F 60. The POS terminal 100 registers the purchased product and performs payment based on the product information transmitted from the reading device 10, and collects the fee from the customer. The POS terminal 100 prints a receipt to be given to the customer.

[0020] The operation of reading the RFID tag 21 by the control unit 30 will be described below mainly with reference to Figures 5 to 7. As described above, the reader 10 of this embodiment can move the movable body 6 only in one direction, the forward and backward directions. For ease of understanding, it is assumed here that the antenna 4 and the magnetic sensor 5 are fixed to the same position on the movable body 6.

[0021] First, the reading operation in the first mode will be described. In the first mode, the control unit 30 determines the position on the placing surface 3 of the area where the bottom 25 of the shopping basket 20 faces the placing surface 3 (hereinafter referred to as the facing area) based on the detection result by the magnetic sensor 5, and switches the strength of the radio waves radiated from the antenna 4 between two levels, "strong" and "weak," based on the relative position of the facing area and the antenna 4. The radio wave strength here means the size of the range in which communication with the RFID tag 21 is possible.

[0022] First, when reading the RFID tag 21 of an item 22 placed in a shopping basket 20, the shopping basket 20 containing the item 22 is placed on the placement surface 3 of the reader 10. In a standby state before starting to read the RFID tag 21, the movable body 6 of the reader 10 is positioned at the rearmost position along the rail 7 shown in FIGS. 2 and 5. In this state, the movable body 6 is located outside the facing area. At this time, the control unit 30 is not detecting magnetism via the magnetic sensor 5, and therefore controls the reader / writer 50 to set the intensity of the radio waves radiated from the antenna 4 to "weak." Alternatively, in the standby state, the control unit 30 controls the reader / writer 50 to set the intensity of the radio waves radiated from the antenna 4 to zero.

[0023] From this state, the control unit 30 energizes the motor 42 to operate the actuator 41 of the movement mechanism 40, causing the movable body 6, which is in the standby position, to move forward along the rail 7. As the movable body 6 moves forward, the magnetic sensor 5 approaches the shopping basket 20 placed on the placement surface 3, and the control unit 30 detects the magnetism emitted from one of the magnets 23 via the magnetic sensor 5. This state is shown in Figure 6. Of the two magnets 23, 24 provided on the shopping basket 20, the one magnet 23 is the magnet that is located upstream in the direction of movement of the movable body 6. In other words, the one magnet 23 is located at the upstream end of the opposing area along the direction of movement of the movable body 6.

[0024] Based on the detection of the magnetism of one of the magnets 23 via the magnetic sensor 5, the control unit 30 determines that the antenna 4 has approached the opposing area of ​​the bottom 25 of the shopping basket 20, and controls the reader / writer 50 to switch the strength of the radio waves emitted from the antenna 4 to "strong." The strength of the radio waves after the switch is strong enough to communicate with the RFID tags 21 of the products 22 in the shopping basket 20.

[0025] Thereafter, while maintaining the radio wave intensity at "strong," the control unit 30 moves the movable body 6 forward to pass through the facing area, communicates with the RFID tags 21 of all the products 22 in the shopping cart 20, and reads the RFID tags 21 of all the products 22 in the shopping cart 20. The control unit 30 then transmits the read product information to the POS terminal 100 via the communication I / F 60.

[0026] Further thereafter, the control unit 30 determines that the antenna 4 has approached the outside of the facing area where the bottom 25 of the shopping basket 20 faces the placing surface 3 based on the detection of the magnetism emitted from the other magnet 24 via the magnetic sensor 5, and controls the moving mechanism 40 to stop the movable body 6. This state is shown in Figure 7.

[0027] At this time, the control unit 30 controls the reader / writer 50 to switch the strength of the radio waves radiated from the antenna 4 from "strong" to "weak." Alternatively, the control unit 30 controls the reader / writer 50 to set the strength of the radio waves radiated from the antenna 4 to zero when the antenna 4 is about to go out of the facing area of ​​the shopping cart 20.

[0028] As described above, when reading RFID tag 21 in the first mode, the radio wave intensity for reading RFID tag 21 can be set to "strong" only when antenna 4 is positioned in the facing area where bottom 25 of shopping basket 20 placed on placing surface 3 faces placing surface 3, and the radio wave intensity can be set to "weak" or "zero" when antenna 4 is moved to a position outside the facing area. Therefore, when reading device 10 of this embodiment operates in the first mode, it is possible to suppress radio waves that are undesirably emitted outside shopping basket 20, preventing the malfunction of erroneously reading RFID tags 21 outside shopping basket 20, and ensuring that only the RFID tags 21 of purchased items placed inside shopping basket 20 are read. Control unit 30 functions as a suppression means for suppressing the emission of unnecessary radio waves.

[0029] Furthermore, when the reading device 10 of this embodiment is operated in the first mode, it can efficiently read the RFID tags 21 of purchased items regardless of the size of the shopping basket 20. For example, when a relatively small shopping basket that holds small items or a small number of items is placed on the placing surface 3, the radio wave intensity emitted from the antenna 4 can be set to "strong" only when the antenna 4 is within the facing area facing the bottom of the small shopping basket, minimizing the travel distance of the antenna 4 and efficiently reading only the RFID tags 21 of the items in the shopping basket.

[0030] Next, the reading operation in the second mode by the reading device 10 of this embodiment will be described. In the second mode, the control unit 30 determines the position of the opposing area within the placing surface 3 where the bottom 25 of the shopping cart 20 faces the placing surface 3 based on the detection results of the magnetic sensor 5, and based on the relative position of the opposing area and the antenna 4, switches the strength of the radio waves emitted from the antenna 4 and changes the movement direction of the antenna 4.

[0031] First, when reading the RFID tag 21 of an item 22 placed in a shopping basket 20, the shopping basket 20 containing the item 22 is placed on the placement surface 3 of the reader 10. In a standby state before starting to read the RFID tag 21, the movable body 6 of the reader 10 is positioned at the rearmost position along the rail 7 shown in FIGS. 2 and 5. In this state, the movable body 6 is located outside the facing area. At this time, the control unit 30 is not detecting magnetism via the magnetic sensor 5, and therefore controls the reader / writer 50 to set the intensity of the radio waves radiated from the antenna 4 to "weak." Alternatively, in the standby state, the control unit 30 controls the reader / writer 50 to set the intensity of the radio waves radiated from the antenna 4 to zero.

[0032] From this state, the control unit 30 energizes the motor 42 to operate the actuator 41 of the movement mechanism 40, causing the movable body 6, which is in the standby position, to move forward along the rail 7. As the movable body 6 moves forward, the magnetic sensor 5 approaches the shopping basket 20 placed on the placement surface 3, and the control unit 30 detects the magnetism emitted from one of the magnets 23 via the magnetic sensor 5. This state is shown in Figure 6. Of the two magnets 23, 24 provided on the shopping basket 20, the one magnet 23 is the magnet that is located upstream in the direction of movement of the movable body 6. In other words, the one magnet 23 is located at the upstream end of the opposing area along the direction of movement of the movable body 6.

[0033] Based on the detection of the magnetism of one of the magnets 23 via the magnetic sensor 5, the control unit 30 determines that the antenna 4 has approached the opposing area of ​​the bottom 25 of the shopping basket 20, and controls the reader / writer 50 to switch the strength of the radio waves emitted from the antenna 4 to "strong." The strength of the radio waves after the switch is strong enough to communicate with the RFID tags 21 of the products 22 in the shopping basket 20.

[0034] Thereafter, while maintaining the radio wave intensity at "strong," the control unit 30 moves the movable body 6 forward to pass through the facing area, communicates with the RFID tags 21 of all the products 22 in the shopping cart 20, and reads the RFID tags 21 of all the products 22 in the shopping cart 20. The control unit 30 then transmits the read product information to the POS terminal 100 via the communication I / F 60.

[0035] Further thereafter, the control unit 30 detects the magnetism emitted from the other magnet 24 via the magnetic sensor 5, and determines that the antenna 4 has reached the outside of the facing area where the bottom 25 of the shopping basket 20 faces the placing surface 3, and controls the moving mechanism 40 to move the movable body 6 in the opposite direction. This state is shown in Figure 7.

[0036] As described above, when reading RFID tag 21 in the second mode, antenna 4 does not move out of the facing area, and radio waves for reading RFID tag 21 can be emitted only when antenna 4 is positioned in the facing area where bottom 25 of shopping basket 20 placed on placing surface 3 faces placing surface 3. Therefore, when reading device 10 of this embodiment is operated in the second mode, radio waves undesirably emitted outside shopping basket 20 can be suppressed, preventing the mistake of erroneously reading RFID tags 21 outside shopping basket 20 and ensuring that only the RFID tags 21 of purchased items placed inside shopping basket 20 are read. Control unit 30 functions as a suppression means for suppressing the emission of unnecessary radio waves.

[0037] Furthermore, when the reading device 10 of this embodiment is operated in the second mode, it can efficiently read the RFID tags 21 of purchased items regardless of the size of the shopping basket 20. For example, when a relatively small shopping basket that holds small items or a small number of items is placed on the placing surface 3, the antenna 4 can radiate radio waves only when it is within the facing area facing the bottom of the small shopping basket, and only the RFID tags 21 of the items in the shopping basket can be efficiently read.

[0038] The second embodiment will be described below with reference to Figures 8 to 14. Note that components that function similarly to the reading device 10 of the first embodiment described above are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0039] As shown in Fig. 8, a reading device 70 according to the second embodiment includes a movable body 6, to which an antenna 4 and a magnetic sensor 5 are fixed, below a top board 2. The reading device 70 includes rails 71 on which the movable body 6 is attached so as to be movable in the left-right direction. The rails 71 are movable in the front-rear direction along the rails 71. In other words, the movable body 6 can be moved in the front-rear and left-right directions within a predetermined rectangular area (movable area) along the placing surface 3 by the movement mechanism 40.

[0040] As shown in FIG. 9 , shopping basket 20 has four magnets 72, 73, 74, and 75 on the outer periphery of its bottom 25. Bottom 25 of shopping basket 20 is roughly rectangular, and magnets 72, 73, 74, and 75 are provided at its four corners. Magnets 72, 73, 74, and 75 are attached to shopping basket 20, for example, with an adhesive. Shopping basket 20 is placed on placing surface 3 with its longitudinal direction oriented along the front-to-rear direction. In the following description, it is assumed that, when shopping basket 20 is placed on placing surface 3, magnet 72 is located on the rear left side, magnet 73 is located on the front left side, magnet 74 is located on the front right side, and magnet 75 is located on the rear right side.

[0041] The magnets 72, 73, 74, and 75 do not necessarily have to be provided on the bottom 25 of the shopping basket 20. The magnets 72, 73, 74, and 75 may be attached to the outer periphery of the shopping basket 20. The outer periphery of the shopping basket 20 includes, for example, a cylindrical peripheral portion 26 extending upward from each side of the bottom 25. The magnets 72, 73, 74, and 75 may also be attached to the peripheral portion 26 closer to the bottom 25. In order to enable the magnetic sensor 5 disposed below the placement surface 3 to efficiently detect the magnetic fields emitted by the magnets 72, 73, 74, and 75, it is desirable to attach the magnets 72, 73, 74, and 75 to the bottom 25 of the shopping basket 20 closer to the placement surface 3.

[0042] The following describes an example of the operation of reading the RFID tag 21 by the control unit 30 of the reading device 70. As described above, the reading device 70 of this embodiment can move the movable body 6 in two directions, the left-right direction and the front-back direction, along the placing surface 3.

[0043] Based on the detection results of the magnetic sensor 5, the control unit 30 determines the position of the opposing area on the placing surface 3 where the bottom 25 of the shopping cart 20 faces the placing surface 3, and based on the relative position of the opposing area and the antenna 4, switches the strength of the radio waves emitted from the antenna 4 between two levels, "strong" and "weak," and changes the direction of movement of the antenna 4.

[0044] First, when reading the RFID tag 21 of the product 22 placed in the shopping basket 20, the shopping basket 20 containing the product 22 is placed on the placement surface 3 of the reading device 70 in the orientation described above. In a standby state before starting to read the RFID tag 21, the movable body 6 of the reading device 70 is positioned at the rearmost position along the rail 7 shown in Figures 8 and 10. In this state, the movable body 6 is located outside the facing area. In other words, the facing area of ​​the shopping basket 20 is a size that is included in the area in which the movable body 6 can move (movable area).

[0045] With the shopping cart 20 placed on the placement surface 3 as described above, the control unit 30 does not detect magnetism via the magnetic sensor 5, and therefore controls the reader / writer 50 to set the intensity of the radio waves radiated from the antenna 4 to "weak." Alternatively, when in a standby state, the control unit 30 controls the reader / writer 50 to set the intensity of the radio waves radiated from the antenna 4 to zero.

[0046] From this state, the control unit 30 controls the movement mechanism 40 to move the rail 71 to which the movable body 6 is attached forward along the rail 7. When the magnetic sensor 5 approaches the shopping basket 20 placed on the placement surface 3 as the movable body 6 moves forward, the control unit 30 detects, via the magnetic sensor 5, the magnetism emitted from, for example, the magnet 72 located on the rear left side. This state is shown in FIG. 11. Note that if the movable body 6 is positioned to the right along the rail 71, or if the shopping basket 20 is positioned to the left side, the magnet whose magnetism is detected via the magnetic sensor 5 may be the magnet 75 on the rear right side.

[0047] Based on the detection of the magnetism of the magnet 72 via the magnetic sensor 5, the control unit 30 determines that the antenna 4 has approached the opposing area of ​​the bottom 25 of the shopping basket 20, and controls the reader / writer 50 to switch the strength of the radio waves emitted from the antenna 4 to "strong." The strength of the radio waves after the switch is strong enough to communicate with the RFID tags 21 of the products 22 in the shopping basket 20.

[0048] Thereafter, while maintaining the radio wave intensity at "strong," the control unit 30 moves the movable body 6 forward to pass through the facing area, communicates with the RFID tag 21 of the product 22 in the shopping basket 20, and reads the RFID tag 21 of the product 22 in the shopping basket 20. The control unit 30 then transmits the read product information to the POS terminal 100 via the communication I / F 60.

[0049] Then, based on the detection of the magnetism emitted from the magnet 73 on the front left side via the magnetic sensor 5, the control unit 30 determines that the antenna 4 has reached the front outside of the facing area where the bottom 25 of the shopping basket 20 faces the placing surface 3, and controls the movement mechanism 40 to stop the forward movement of the movable body 6. This state is shown in Figure 12.

[0050] Thereafter, the control unit 30 changes the direction of movement of the movable body 6 to the right and continues to read the RFID tag 21. Then, based on the magnetic sensor 5 detecting the magnetism of the magnet 74 on the front right side, the control unit 30 stops the movement of the movable body 6 to the right. This state is shown in FIG.

[0051] After this, the control unit 30 further changes the direction of movement of the movable body 6 backward and continues reading the RFID tag 21, and stops the backward movement of the movable body 6 when the magnetic sensor 5 detects the magnetism of the magnet 75 on the rear right side. This state is shown in Figure 14. After this, the control unit 30 further changes the direction of movement of the movable body 6 leftward and continues reading the RFID tag 21, and stops the movable body 6 based on the detection of the magnetism of the magnet 72 on the rear left side by the magnetic sensor 5, and sets the strength of the radio waves radiated via the antenna 4 to zero, thereby ending the operation of reading the RFID tag 21.

[0052] As described above, according to the second embodiment, the radio wave intensity for reading the RFID tag 21 can be set to "strong" only when the antenna 4 is positioned in the facing area where the bottom 25 of the shopping basket 20 placed on the placing surface 3 faces the placing surface 3, and the radio wave intensity can be set to "weak" or "zero" when the antenna 4 is moved to a position outside the facing area. Therefore, according to this embodiment, radio waves that are undesirably emitted outside the shopping basket 20 can be suppressed, the problem of erroneously reading RFID tags 21 outside the shopping basket 20 can be prevented, and only the RFID tags 21 of purchased items placed inside the shopping basket 20 can be reliably read. In other words, the control unit 30 functions as a suppression means for suppressing the emission of unnecessary radio waves.

[0053] Furthermore, according to the second embodiment, the RFID tags 21 of purchased products can be read efficiently regardless of the size of the shopping basket 20. For example, when a relatively small shopping basket that holds small products or a small number of products is placed on the placing surface 3, the radio wave intensity emitted from the antenna 4 can be set to "strong" only when the antenna 4 is located within the facing area facing the bottom of the small shopping basket, thereby minimizing the travel distance of the antenna 4 and enabling efficient reading of only the RFID tags 21 of the products in the shopping basket.

[0054] Furthermore, according to the second embodiment, the magnet attached to the outer periphery of the shopping basket 20 placed on the placing surface 3 is detected and only the RFID tag 21 in the facing area that the shopping basket 20 faces is read, so that the RFID tag 21 of the purchased item can be reliably read no matter where the shopping basket 20 is placed within the movable area of ​​the antenna 4. In this way, by making the movable area of ​​the antenna 4 larger than the facing area of ​​the shopping basket 20, the RFID tag 21 can be reliably read without having to worry about where the shopping basket 20 is placed on the placing surface 3.

[0055] In the above-described embodiment, the magnetic sensor 5 is used as the detector for detecting the facing area of ​​the shopping basket 20, and the magnets 23, 24 (72-75) are used as the detected parts, but any other detection means may be used. For example, the magnetic sensor 5 may be omitted, and an RFID tag for detecting the facing area of ​​the shopping basket 20 may be attached to the shopping basket 20 instead of the magnet, and the facing area may be detected by reading the RFID tag attached to the shopping basket 20 via the antenna 4.

[0056] In addition, in the above-described embodiment, for ease of explanation, it is assumed that the antenna 4 and the magnetic sensor 5 are provided at the same position on the movable body 6, but in an actual device, the antenna 4 and the magnetic sensor 5 are aligned in a direction along the mounting surface 3 as shown in the figure. Therefore, in actual control, it is necessary to determine the timing for moving and stopping the movable body 6 and the timing for switching the strength of the radio waves emitted from the antenna 4, taking into consideration the horizontal misalignment between the antenna 4 and the magnetic sensor 5.

[0057] Although the embodiments of the present invention have been described above, the above-described embodiments are presented as examples and are not intended to limit the scope of the invention. The above-described embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. The above-described embodiments are included within the scope of the invention, as well as within the scope of the inventions described in the claims and their equivalents. [Explanation of symbols]

[0058] 10, 70...reading device, 2...top plate, 3...placing surface, 4...antenna, 5...magnetic sensor, 6...movable body, 7, 71...rail, 20...shopping basket, 21...RFID tag, 23, 24, 72, 73, 74, 75...magnet, 25...bottom, 26...periphery, 30...control unit, 40...moving mechanism, 50...reader / writer, 100...POS terminal.

Claims

1. a detection target attached to the outer periphery of a shopping cart containing an item having an RFID tag; a basket stand on which the shopping basket is placed; an antenna disposed under the basket stand for emitting radio waves to communicate with the RFID tags of the products in the shopping basket placed on the basket stand; a detecting unit disposed under the basket stand and configured to detect the detected unit attached to the shopping basket placed on the basket stand; a moving means for moving a movable body to which the antenna and the detection unit are fixed along the car stand; a suppression means for suppressing radio waves emitted outside the shopping cart when the detection unit of the movable body, which is moving with the antenna disposed in an opposing area facing the shopping cart, detects the detected unit; A reading device having:

2. the detected part is a magnet attached to the outer periphery of the bottom of the shopping basket, The detection unit is a magnetic sensor that detects the magnetic field emitted by the magnet. The reading device according to claim 1 .

3. The suppression means weakens the intensity of the radio waves radiated from the antenna when the detection unit of the movable body, which is moving with the antenna disposed in an opposing area opposing the shopping cart, detects the detected unit. The reading device according to claim 1 .

4. When the detection unit of the movable body, which is moving with the antenna disposed in an opposing area facing the shopping cart, detects the detected part, the suppression unit controls the movement unit to change the movement direction of the movable body so that the antenna does not move out of the opposing area. The reading device according to claim 1 .

5. A movable area in which the movable body can move is a size that includes the facing area. The reading device according to claim 1 .

Images