Patent Publication Number: US-2022230032-A1

Title: Wireless tag reader and basket device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2021-008284, filed on Jan. 21, 2021, the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments described herein relate generally to a wireless tag reader, a basket device, and a checkout system. 
     BACKGROUND 
     In recent years, radio frequency identification (RFID) technology has started to be utilized in a distribution systems, logistics systems, and the like. In such systems, tag information stored in an RFID tag (wireless tag) attached to an article, item, or commodity is read and is used for tracking the article, item or commodity. 
     For example, in a large retailer such as a supermarket, a shopping cart to which a wireless tag reader is attached has been proposed. When a customer puts a commodity in such a shopping cart, commodity information can be read from the wireless tag on the commodity by the wireless tag reader. 
     The commodity information read by the wireless tag reader is transferred from the wireless tag reader to a checkout device according to an operation of the customer during checkout. With this configuration, the customer can perform checkout or payment with the checkout device for commodities put in the shopping cart. By adopting a shopping cart equipped with a wireless tag reader, commodity information registration (hereinafter, also referred to as commodity registration) needed for the customer to perform checkout can be easily performed. 
     However, tag information may not always be read from a wireless tag on a commodity depending on a positional relationship between the antenna of the wireless tag reader and the wireless tag. For example, if the antenna surface of the wireless tag reader and the antenna surface of the wireless tag are perpendicular or substantially perpendicular, reading performance of the wireless tag reader is deteriorated. Since a commodity can be put in the shopping cart by the customer in any orientation, the reading performance may sometimes be poor due to the positional relationship between the wireless tag and the wireless tag reader. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating a checkout system including a basket device according to a first embodiment. 
         FIG. 2  is a diagram illustrating an outline of a basket device to which a wireless tag reader is attached. 
         FIG. 3  is a diagram schematically illustrating an internal structure of a wireless tag reader. 
         FIG. 4  is a diagram schematically illustrating a structure to hold a wireless tag reader when viewed from an upper surface thereof. 
         FIG. 5  is a hardware block diagram of a wireless tag reader. 
         FIG. 6  is a functional block diagram of a wireless tag reader. 
         FIG. 7  is a diagram illustrating a holding member and a wireless tag reader according to a second embodiment in an unattached state. 
         FIG. 8  is a diagram illustrating a holding member and a wireless tag reader according to a second embodiment in an attached state. 
         FIG. 9  is a diagram schematically illustrating an internal structure of a wireless tag reader according to a third embodiment. 
         FIG. 10  is a diagram schematically illustrating a wireless tag reader according to a third embodiment when viewed from an upper surface thereof. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments provide a wireless tag reader and a basket device capable of improving performance for reading tag information. 
     In general, according to one embodiment, a wireless tag reader includes a casing, an antenna in the casing and through radio waves are transmitted to and received from a wireless tag on an article. A control device is in the casing and configured to read tag information stored in the wireless tag based on a radio wave received by the antenna. An elastic member is between an inner surface of the casing and the antenna. 
     Hereinafter, a wireless tag reader and a basket device according to embodiments will be described in detail with reference to the drawings. The present disclosure is not limited to the embodiments described below. For example, in the embodiments described below, a wireless tag reader and a shopping basket used in a mass retailer (hereinafter, also referred to as a store) such as a supermarket and to which the wireless tag reader is attached will be described. However, the wireless tag reader can be attached to any type of device that can store commodities for sale such as a shopping cart. Additionally, the wireless tag reader can be attached to a device for storing mechanical or electrical parts in a factory or the like. 
     First Embodiment 
     First, a first embodiment will be described.  FIG. 1  is a diagram illustrating a checkout system  1  including a basket device  2  according to the first embodiment. The checkout system  1  includes the basket device  2 , a portable terminal  3 , and a checkout machine  4 . 
     The basket device  2  includes a shopping basket  21  and a wireless tag reader  22  that is detachably held in the shopping basket  21 . 
     A large number of shopping baskets  21  are provided in a store and carried by customers moving in the store. The shopping basket  21  includes a holding portion  211  with the upper side open and a grip portion  212  rotatably attached to an upper end portion of the holding portion  211 . The holding portion  211  is formed in a grid pattern and holds commodities purchased by the customer inside. A wireless tag stores commodity information related to the commodity to which the wireless tag is attached. The grip portion  212  is gripped by the customer during shopping. 
     The wireless tag reader  22  is detachably held in the shopping basket  21 . The wireless tag reader  22  is attached to the shopping basket  21  by a customer or a clerk. For example, the wireless tag reader  22  is put in the holding portion  211  through an upper opening of the holding portion  211  and, as illustrated in  FIG. 2 , is placed on a bottom surface portion  213  of the shopping basket  21  and is held in the shopping basket  21  by fitting an outer peripheral surface thereof into the holding portion  211 . Once the customer&#39;s shopping is finished, the shopping basket  21  is returned to the clerk, who removes the wireless tag reader  22  from the shopping basket  21  and sets the wireless tag reader  22  in a charger to charge a battery (see  FIG. 3 ) provided in the wireless tag reader  22 . By making the wireless tag reader  22  detachable from the shopping basket  21 , a wireless tag reader  22  does not need to be attached to every one of the shopping baskets  21  in the store, and the financial burden on the store can be reduced. The wireless tag used in this embodiment is a passive type wireless tag that operates (responds) by using radio waves from the wireless tag reader  22  as a power source. 
     The portable terminal  3  is a smartphone, a tablet terminal, or the like owned by a customer or rented by a store, and stores an application program prepared for the checkout system  1 . The portable terminal  3  executes various processing related to commodity registration and checkout processing according to a customer&#39;s operation. For example, the portable terminal  3  acquires and stores commodity information read from a wireless tag by the wireless tag reader  22  by wireless communication. The portable terminal  3  transmits the stored commodity information to the checkout machine  4  by wireless communication. The commodity information includes a commodity code, a price, a commodity name, and the like of the commodity to which the wireless tag is stuck. 
     The checkout machine  4  is a so-called self-service-type checkout machine with which, for example, the customer performs a checkout operation by himself or herself. The checkout machine  4  executes checkout processing by cash payment or cashless payment such as credit payment based on the commodity information received from the portable terminal  3 . Checkout processing is processing of making payment for the commodities purchased by the customer. 
     Next, a configuration of the wireless tag reader  22  will be described in detail.  FIG. 3  is a diagram schematically illustrating an internal structure of the wireless tag reader  22 , and  FIG. 4  is a diagram schematically illustrating a structure of the wireless tag reader  22  when viewed from the upper surface thereof. The wireless tag reader  22  includes a casing  221 . 
     The casing  221  can be detachably attached to the shopping basket  21 . The casing  221  is formed in a shape that fits into the shopping basket  21  (for example, trapezoidal cross-sectional shaped), includes a placement portion  222  on the upper surface thereof, and houses a main body portion  223  inside thereof. The placement portion  222  is made of a material, for example, resin, that transmits the radio wave used by the wireless tag reader  22 . The placement portion  222  has an upper surface that is flat, and commodities to be purchased by the customer are placed thereon while the wireless tag reader  22  is held by the shopping basket  21 . 
     The main body portion  223  is formed in a substantially rectangular parallelepiped shape, for example, and one ends of coil springs  224  are respectively attached to four sides of the outer peripheral surface thereof. The other ends of the coil springs  224  are respectively attached to the inner peripheral surface of the casing  221 . With this configuration, the main body portion  223  is elastically supported in the casing  221  via the coil springs  224 . The main body portion  223  is guided in a direction along the placement portion  222  by a guide or the like formed on the casing  221 . For that reason, as the coil springs  224  extend and contract, the main body portion  223  can move in the direction along the placement portion  222  with respect to the casing  221 . When the wireless tag reader  22  is mounted on the shopping basket  21 , the main body portion  223  can move along the bottom surface portion  213 . The main body portion  223  is formed in a hollow shape, and houses an antenna  225 , a control device  226 , and a battery  227 . Each of the coil springs  224  is an elastic member that elastically supports the antenna  225  on the casing  221 , and elastically supports the main body portion  223  on the casing  221 . The elastic member is not limited to a spring member and may be made of rubber, other elastic material, or the like. 
     The antenna  225  is provided in the casing  221  and transmits and receives radio waves to and from a wireless tag stuck to a commodity. Specifically, the antenna  225  transmits a radio wave to a commodity placed on the placement portion  222 , that is, a wireless tag stuck to the commodity in the holding portion  211 , and receives a response wave transmitted by the wireless tag. In the following description, a radio wave transmitted by the antenna  225  may be referred to as an inquiry wave, and a radio wave received by the antenna  225  from the wireless tag may be referred to as a response wave. 
     The control device  226  includes various electrical components for controlling the wireless tag reader  22 . The battery  227  supplies power to each component of the wireless tag reader  22 . The battery  227  is charged when the wireless tag reader  22  is placed on a charging stand or the like. 
     As described above, the main body portion  223  is elastically supported in the casing  221 . For that reason, if a customer moves with the shopping basket  21  during shopping, an inertial force acts on the main body portion  223  due to a change in acceleration accompanying the movement, and the coil springs  224  extend and contract. With this configuration, the main body portion  223  moves in the direction along the placement portion  222  with respect to the casing  221 . 
     In one embodiment, the wireless tag reader  22  may be held on a side surface portion of the shopping basket  21 . In such a case, for example, the wireless tag reader  22  is disposed so that the antenna  225  faces the inside of the holding portion  211 . If a customer moves with the shopping basket  21 , the shopping basket  21  also moves in the vertical direction, and thus the antenna  225  moves along the side surface of the shopping basket  21  due to the inertial force applied in the vertical direction. Hereinafter, the movement of the antenna  225  and the main body portion  223  with respect to the casing  221  may be simply referred to as movement. 
     As described above, the main body portion  223  including the antenna  225  is attached to the casing  221  via the coil springs  224 , so that the main body portion  223  can be moved along the bottom surface portion  213  of the shopping basket  21 . A movable distance of the antenna  225  can be set by an elastic force of the coil springs  224 . Although the movable distance varies depends on the usage environment and the like, according to an experimental result, the antenna should be movable by, for example,  2  cm or more in order to change the positional relationship between the antenna  225  and the wireless tag to improve reading performance. Radio wave intensity of the inquiry wave transmitted from the antenna  225  is set so that the wave can reach a wireless tag disposed inside the holding portion  211  and cannot reach any wireless tag stuck to a commodity disposed on a commodity display shelf outside the holding portion  211 . 
     Subsequently, a hardware configuration of the wireless tag reader  22  will be described.  FIG. 5  is a hardware block diagram of the wireless tag reader  22 . The components shown in  FIG. 5  are included in the main body portion  223  of the wireless tag reader  22 . 
     The wireless tag reader  22  includes a control unit  200 , a storage unit  210 , an input and output controller  220 , a power supply circuit  230 , and a communication unit  240 . The control unit  200 , the storage unit  210 , the input and output controller  220 , the power supply circuit  230 , and the communication unit  240  are connected to each other via a bus  250 . 
     The control unit  200  includes a central processing unit (CPU)  201 , a read only memory (ROM)  202 , and a random access memory (RAM)  203 . The CPU  201 , ROM  202 , and RAM  203  are connected to each other via the bus  250 . 
     The CPU  201  controls the overall operation of the wireless tag reader  22 . The ROM  202  stores various programs to be executed by the CPU  201  and various data. The RAM  203  is used as a work area of the CPU  201 , and various programs and various data stored in the ROM  202  and the storage unit  210  are loaded in the RAM  203 . The CPU  201  of the control unit  200  executes various control processing of the wireless tag reader  22  according to a control program stored in the ROM  202  or the storage unit  210  and loaded in the RAM  203 . 
     The storage unit  210  is a hard disk drive (HDD) or a flash memory, and maintains stored data even if power is interrupted. The storage unit  210  stores various control programs. The control programs stored in the storage unit  210  include, for example, a program that causes the control unit  200  to perform the function of the wireless tag reader  22 . 
     The input and output controller  220  is connected to the antenna  225  and a sensor  228 . The input and output controller  220  has a function as an input and output interface for connected hardware and a function for controlling the hardware. With this configuration, the control unit  200  can transmit and receive information or data to and from the antenna  225  and the sensor  228  via the input and output controller  220 , and can control the hardware based on instructions of the control unit  200 . The sensor  228  detects that the wireless tag reader  22  is mounted on the shopping basket  21 , and is, for example, a pressure sensitive sensor provided in the casing  221 . 
     The power supply circuit  230  is connected to the battery  227 . The power supply circuit  230  is a circuit that supplies power to each hardware of the wireless tag reader  22 . The power supply circuit  230  supplies power to each hardware by stepping down a voltage supplied from the battery  227  to an operating voltage of each hardware. 
     The communication unit  240  is an interface for communicating with an external device. For example, the communication unit  240  connects to the portable terminal  3  and outputs commodity information read by the wireless tag reader  22  to the portable terminal  3 . 
     Next, a functional configuration of the control unit  200  of the wireless tag reader  22  will be described.  FIG. 6  is a functional block diagram of the wireless tag reader  22 . 
     The CPU  201  executes the control program stored in the ROM  202  or the storage unit  210  to perform the functions of a radio wave control unit  2001 , a reading unit  2002 , and an output unit  2003 . 
     The radio wave control unit  2001  controls a radio wave to be transmitted from the antenna  225 . Specifically, if the sensor  228  detects that the wireless tag reader  22  is mounted on the shopping basket  21 , the radio wave control unit  2001  controls the radio wave so as to be transmitted from the antenna  225  at predetermined intervals or continuously. If the sensor  228  detects that the wireless tag reader  22  is removed from the shopping basket  21 , the radio wave control unit  2001  stops transmitting the radio wave from the antenna  225 . Furthermore, the radio wave control unit  2001  controls radio wave intensity of the radio wave transmitted from the antenna  225  so that the radio wave can reach a wireless tag disposed inside the holding portion  211  of the shopping basket  21 , and cannot reach any wireless tag stuck to a commodity disposed on a commodity display shelf. 
     The reading unit  2002  reads tag information stored in the wireless tag based on the radio wave received by the antenna  225 . Specifically, the reading unit  2002  reads the tag information included in the response wave transmitted by the wireless tag with respect to the inquiry wave transmitted by the antenna  225 . The tag information read by the reading unit  2002  includes commodity information of the commodity to which the wireless tag is stuck. 
     The output unit  2003  controls the communication unit  240  to transmit or output the commodity information included in the tag information read by the reading unit  2002  to the portable terminal  3 . For example, the output unit  2003  controls the communication unit  240  to output commodity information in response to an instruction signal from the portable terminal  3 . 
     A use case of the basket device  2  having the configuration described above will be described. When shopping, a customer who visits a store takes out the shopping basket  21  from a shopping cart storage area and also takes out the wireless tag reader  22  from a charging stand. Next, as illustrated in  FIG. 2 , the wireless tag reader  22  is positioned on the bottom surface portion  213  of the holding portion  211  of the shopping basket  21 . In this case, the outer peripheral surface of the wireless tag reader  22  fits with the lower inner peripheral surface of the holding portion  211 , so that the wireless tag reader  22  is held in or mounted on the shopping basket  21 . In this state, the sensor  228  detects that the wireless tag reader  22  is held in the shopping basket  21 , and the wireless tag reader  22  transmits an inquiry wave from the antenna  225 . 
     The customer moves around the store with the shopping basket  21 . If there is a commodity to be purchased, the customer puts the commodity in the holding portion  211  of the shopping basket  21 . The wireless tag stuck to the commodity in the holding portion  211  receives the inquiry wave from the antenna  225  and transmits a response wave to the antenna  225 . 
     In the wireless tag reader  22 , the antenna  225  receives the response wave from the wireless tag, and the reading unit  2002  reads commodity information from the response wave. The read commodity information is output by the output unit  2003  from the communication unit  240  to the portable terminal  3 . The portable terminal  3  stores the commodity information and displays the commodity information on its own display unit. 
     Since the reading unit  2002  reads commodity information at predetermined intervals or continuously, the commodity information of the commodity can be read as soon as the customer puts a commodity in the shopping basket  21 . The reading unit  2002  repeatedly reads the commodity information of the commodity stored in the holding portion  211 , and executes a duplication check to prevent double reading of the repeatedly read commodity information based on an identifier of the read wireless tag. With this configuration, the reading unit  2002  can read the commodity information of the commodities in the shopping basket  21  without duplication. Then, if the reading unit  2002  reads new commodity information, the output unit  2003  controls the communication unit  240  to output the new commodity information to the portable terminal  3 . The portable terminal  3  sequentially stores the received commodity information and displays the received commodity information on its own display unit. The output unit  2003  may control the communication unit  240  to repeatedly output all of the commodity information repeatedly read by the reading unit  2002 . In such a case, the portable terminal  3  compares all the received commodity information with the previously received and stored commodity information, and adds, stores, and displays the newly received commodity information. 
     If the customer performs checkout, the commodity information stored in the portable terminal  3  is transmitted to the checkout machine  4  according to the operation of the customer. The checkout machine  4  executes checkout processing based on the received commodity information. 
     If the reading unit  2002  reads commodity information during the shopping described above, depending on the positional relationship between the wireless tag stuck to the commodity in the holding portion  211  and the antenna  225  of the wireless tag reader  22 , the transmission and reception of radio waves between the antenna  225  and the wireless tag may not be good and the reading unit  2002  may not be able to read the commodity information. 
     However, according to the wireless tag reader  22  of this embodiment, since the shopping basket  21  is moved during shopping, an inertial force is applied to the wireless tag reader  22 , and the main body portion  223  including the antenna  225  moves along the bottom surface portion  213  of the shopping basket  21 . For that reason, the positional relationship between the antenna  225  and the wireless tag changes as the shopping basket  21  moves during shopping. Accordingly, tag information of a wireless tag that could not be read at the point in time if the commodity was in the holding portion  211  can also be read due to the change in the positional relationship between the antenna  225  and the wireless tag, and performance for reading the commodity information of the commodity in the shopping basket  21  is improved. Moreover, the wireless tag reader of this embodiment improves the reading performance of the reading unit  2002  by a simple configuration in which the antenna  225  is attached to the casing  221  via an elastic member in view of the fact that the shopping basket  21  is moved by the customer during use and to which inertial force is applied. Accordingly, a drive mechanism for moving the antenna  225  does not need to be provided, and the configuration of the wireless tag reader  22  can be prevented from becoming complicated. 
     According to the wireless tag reader  22  of this embodiment, the main body portion  223  elastically supported on the casing  221  includes not only the antenna  225  but also electrical components of the wireless tag reader  22  such as the control device  226  and the battery  227 . For that reason, even if an impact is applied when the wireless tag reader is being removed from the shopping basket  21 , those components can be protected by a cushioning action by the coil springs  224 . That is, the coil springs  224  have a function of movably supporting the antenna  225  when the wireless tag reader  22  is being held in the shopping basket  21 , and a function of a cushioning member for protecting the device components when the wireless tag reader  22  is removed from the shopping basket  21 . For that reason, a cushioning member for protecting the device components does not need to be separately provided for when the wireless tag reader  22  is not attached to the shopping basket  21 . 
     According to the wireless tag reader  22  of this embodiment, by making the wireless tag reader  22  detachable from the shopping basket  21 , there is an advantage that the store does not need to prepare as many wireless tag readers  22  as the shopping baskets  21  and the shopping basket  21  does not disturb charging of the battery  227 . 
     The wireless tag reader  22  may be configured to be fixedly provided on the shopping basket  21 . Furthermore, a configuration in which the antenna  225  is attached to the casing  221  via the coil springs  224  is adopted as a configuration in which the antenna  225  can be moved with respect to the casing  221  by the inertial force applied to the shopping basket  21 , but is not limited to this configuration. For example, a rail on which the antenna  225  can slide may be provided on the bottom surface of the casing  221 . 
     Second Embodiment 
     The second embodiment differs from the first embodiment in that the wireless tag reader  22  includes a detachable holding member  229 .  FIG. 7  is a diagram illustrating the wireless tag reader  22  and the holding member  229  in an unattached state.  FIG. 8  is a diagram illustrating the wireless tag reader  22  and the holding member  229  in an attached state. In the following description, the same reference numerals are given to the same configurations as those of the first embodiment, and the description thereof will be omitted. 
     The wireless tag reader  22  includes the holding member  229 . The holding member  229  is detachably provided on the casing  221  and holds the casing  221  in the shopping basket  21 . Specifically, the holding member  229  is formed of an elastic member such as rubber and is mounted on the casing  221  so as to cover the casing  221 , and fits into the holding portion  211  of the shopping basket  21  to hold the casing  221  in the shopping basket  21 . 
     As illustrated in  FIG. 7 , the holding member  229  includes a top surface portion  2291  and a side surface portion  2292 . The top surface portion  2291  is formed in a rectangular shape and covers the upper surface of the casing  221  when the holding member  229  is mounted on the casing  221 . The side surface portion  2292  is formed so as to project downward from four sides of the top surface portion  2291 , and covers the side surfaces of the casing  221  when the holding member  229  is mounted on the casing  221 . In a left and right direction in  FIG. 7 , a length between the opposing inner surfaces of the side surface portion  2292  is formed to be slightly shorter than a full, expanded width of the casing  221 . In the direction orthogonal to the page surface in  FIG. 7 , the length between the opposing inner surfaces of the side surface portion  2292  can be formed to be substantially equal to the width of the casing  221  while still permitting accommodation of the casing  221  within the holding member  229 . 
     When the holding member  229  is placed in contact with the housing  221  with side surface(s)  2292  expand in the left and right direction in  FIG. 7  but the side surface portions  2292  return towards the unexpanded state, thus the holding member  229  is held against the casing  221 , as illustrated in  FIG. 8 . A plurality of types of holding members  229  having different external dimensions can be prepared, and a holding member  229  can be appropriately selected according to the size of the shopping basket  21  to which the wireless tag reader  22  is to be attached. Other than this, the method of using the basket device  2  is the same as that of the first embodiment. 
     According to the wireless tag reader  22  of this second embodiment, by selecting the appropriate holding member  229  to be mounted on the casing  221 , the wireless tag reader  22  can fit into shopping baskets  21  of different sizes. Accordingly, since different casings suitable for different shopping baskets  21  need not to be prepared, cost reduction and efficiency can be achieved. 
     Third Embodiment 
     The third embodiment differs from the first embodiment and the second embodiment in that the control device  226  and the battery  227  are fixed to the casing  221 .  FIG. 9  is a diagram schematically illustrating an internal structure of the wireless tag reader  22 .  FIG. 10  is a diagram schematically illustrating the wireless tag reader  22  when viewed from the upper surface thereof. In the following description, the same reference numerals are given to the same configurations as those of the first embodiment and the second embodiment, and the description thereof will be omitted. 
     As illustrated in  FIGS. 9 and 10 , a reader housing  30  and an antenna housing  40  are provided in the casing  221 . 
     The reader housing  30  is fixed to the casing  221  via support members  31 . The support members  31  are provided at the upper and lower positions of four corners of the reader housing  30  of a rectangular parallelepiped shape. The reader housing  30  houses the parts of the wireless tag reader  22  excluding the antenna  225 , such as the control device  226  and the battery  227 . 
     The antenna housing  40  is provided so as to be movable with respect to the casing  221  via the coil springs  224 . The antenna housing  40  houses the antenna  225 . The antenna  225  is connected to the control device  226  via a coaxial cable  50  (see  FIG. 10 ). The coaxial cable  50  connects the antenna  225  and the control device  226  with looseness that can allow the antenna housing  40  to move with respect to the reader housing  30  fixed to the casing  221 . 
     The wireless tag reader  22  is used by being attached to the bottom surface portion  213  of the shopping basket  21 , similarly to in the first embodiment. 
     According to the wireless tag reader  22  of this embodiment, since the shopping basket  21  is moved during shopping, similarly to the first embodiment, an inertial force is applied to the wireless tag reader  22  and the antenna housing  40  moves along the bottom surface portion  213  of the shopping basket  21 . For that reason, the positional relationship between the antenna  225  and the wireless tag changes as the shopping basket  21  moves during shopping, and performance for reading commodity information about a commodity in the shopping basket  21  is improved. 
     In addition, since the control device  226  and the battery  227 , which are relatively heavy in weight, of the wireless tag reader  22  do not move with respect to the shopping basket  21 , the impact on the customer with the shopping basket  21  can be reduced. 
     As described above, the wireless tag reader  22  according to the embodiments described above includes the antenna  225  that transmits and receives the radio wave to and from the wireless tag stuck to a commodity, the casing  221  that houses the antenna  225 , the reading unit  2002  that reads tag information stored in the wireless tag based on the radio wave received by the antenna  225 , and the coil spring  224  that elastically supports the antenna  225  so as to be movable with respect to the casing  221 . 
     With this configuration, by providing the wireless tag reader  22  in the shopping basket  21 , the positional relationship between the antenna  225  and the wireless tag stuck to a commodity in the shopping basket  21  can be changed as the shopping basket  21  is moved, and thus the chance for reading the tag information of the wireless tag is increased, thereby the reading performance of the wireless tag reader  22  can be improved. 
     The antenna  225  can be moved by the inertial force accompanying the movement of the shopping basket  21  without giving an impact to the antenna  225 . 
     Furthermore, the wireless tag reader  22  of the embodiments described above includes the main body portion  223  that houses the antenna  225 , the control device  226  that functions as the reading unit  2002 , and the battery  227  that supplies power to the control device  226 , and the coil spring  224  (or other elastic member) elastically supports the main body portion  223  on the casing  221 . 
     With this configuration, even if an impact is applied when the wireless tag reader  22  is being removed from the shopping basket  21 , the components in the main body portion  223  can be protected by the cushioning action by the elastic member. The coil spring  224  can have a function of movably supporting the antenna  225  while the wireless tag reader  22  is held in the shopping basket  21 , and also function as a cushioning member for protecting the components when the wireless tag reader  22  is removed from the shopping basket  21 . As such, the overall structure of the wireless tag reader  22  can be simplified since coil spring  224  (elastic member) can have a plurality of functions. 
     In addition, the wireless tag reader  22  according to the second embodiment includes a holding member  229  that is detachably provided on the casing  221  and holds the casing  221  in the shopping basket  21 . 
     With this configuration, by preparing a plurality of types of holding members  229  having different sizes, the wireless tag reader  22  can be mounted on various shopping baskets  21  having different sizes. Accordingly, the casing  221  does not need to be prepared for shopping baskets  21  having different sizes. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.