Patent Publication Number: US-2012031971-A1

Title: Storage rack with automatic tag reading device and product for placement in such a storage rack

Description:
CROSS-REFERENCE 
     The present application is a continuation of U.S. patent application Ser. No. 12/064,458, filed Aug. 22, 2006, and entitled ‘Storage Rack with Automatic Tag Reading Device and Information Processing System Comprising such a Storage Rack’, the entirety of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     This invention relates to a storage rack with automatic tag reading device and a product for placement in such a storage rack. The invention may be used, for example, for storage of hospital supplies, medical products and medications and replenishment of such stocks. 
     BACKGROUND 
     The use of electronic tags, such as RFID (RadioFrequency IDentification) tags poses numerous problems when they are in the presence of metallic parts, such as metallic cans used for the storage of objects, liquids or food. The electromagnetic field used to read these electronic tags is in fact disturbed by the metallic parts, impairing, if not preventing, communication with the electronic tag. 
     SUMMARY 
     This invention aims to overcome these disadvantages. 
     According to a an aspect of the invention, a product having the shape of a rectangular parallelepiped comprises at least one metallic part with at least one narrow edge, an electronic tag having one antenna positioned substantially perpendicular to a narrow edge of said at least one metallic part, and a paper label positioned on at least one of the following sides of the product: (i) a side opposite to a side of the product bearing said electronic tag, and (ii) a side of the product adjacent to a side of the product bearing said electronic tag on one of its small sides. 
     When the product is stored, in a stack or vertically in a cabinet, the user is encouraged to position it so that its paper label is visible. Due to this position, the electronic tag is positioned toward an antenna positioned so as to read the electronic tag. The electronic tag can be read despite the proximity of the metallic part and the electronic tag. 
     The electronic tag antenna advantageously has a width, measured in the direction of the thickness of the metallic part, greater than the thickness of the edge of the metallic part opposite which the antenna is positioned. 
     The product as outlined above advantageously comprises said electronic tag on one of its four smallest sides. 
     According to a further aspect of the invention, a rack comprises means to read electronic tags comprising at least one antenna in at least one of wall of said rack and shelves supporting products as outlined above. 
     The reading means advantageously comprise a plurality of antennas and electronic signal generation circuits adapted to successively control the generation of electromagnetic fields by different sets of antennas. 
     Thanks to these arrangements, antennas oriented along different axes, which can be orthogonal to one another, can be read successively. 
     Advantages, aims and special features of this rack are similar to those of the product as outlined above. 
     Various aspects of this invention, their main characteristics and their special characteristics may be combined to form an efficient product identification system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other advantages, aims and features of this invention will appear on reading the following description, given for a non-limiting explanatory purpose and referring to the attached drawings in which: 
         FIG. 1  is a diagrammatic representation of a first mode of realization of a rack according to this invention; 
         FIG. 2  is a diagrammatic representation of a second mode of realization of a rack according to this invention; 
         FIG. 3  is a diagrammatic representation of a first shape of antenna incorporated in a rack illustrated in  FIG. 1  or  2 ; 
         FIG. 4  is a diagrammatic representation of a second shape of antenna incorporated in a rack illustrated in  FIG. 1  or  2 ; 
         FIG. 5  is a diagrammatic representation of a third shape of antenna incorporated in a rack illustrated in  FIG. 1  or  2 ; 
         FIG. 6  represents a product especially adapted to be stored in a rack as illustrated in  FIG. 1 ; 
         FIG. 7  represents, as a logic diagram, the operation of a rack as illustrated in  FIG. 1  or  2 ; 
         FIG. 8  represents a information processing system according to this invention and comprising a plurality of racks as illustrated in  FIG. 1  or  2  and 
         FIG. 9  represents a flowchart showing the operation of the information processing system illustrated in  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a rack  100  comprising, in or on its back wall  105 , an antenna  110 , in its upper part, electronic circuits  115 , shelves  120  supporting products  125  equipped with electronic tags  160 , an electric lock  150 , a communication means  155 , two doors  130  of which one supports a reader  135  to read an identification card  140  and a display  145 , a door closure sensor  170  and an emergency opening button  175 . 
     The rack  100 , the shelves  120  and the doors  130  are made from rigid materials, for example wood, glass or plastic. 
     The antenna  110  is connected to the back wall  105 , for example by gluing, stapling or inclusion. The antenna  110  may have one of the antenna shapes illustrated in  FIGS. 3 to 5 . 
     The electronic tags  160  and the electronic circuits  115  are of type known in the field of radio frequency identification (RFID). They comprise, in a known manner, a signal generation circuit adapted to successively generate signals for each antenna or set of antenna incorporated in the rack (see also  FIG. 2 ) and a circuit for reception of signals modulating said magnetic field. 
     The electronic circuits  115  may comprise, for example, a processor and circuits specific to the field of RFID electronic tags. These are adapted to supply to the antenna  110 , at times predetermined according to the closure of the doors  130 , a signal enabling generation an electromagnetic field. This electromagnetic field is used to power the electronic tags  160  and transmit messages, requests or instructions to the tags  160 . The electronic circuits  115  are also adapted to detect the signals transmitted by the electronic tags  160 , by modulation of the magnetic field transmitted by the antenna  110 , to process these signals, to identify the electronic tags and to transmit these identifiers to the communication means  155 . 
     The electronic circuits  115  are also adapted to process the signals from the card reader  135  to identify a user and, to control the operation of the electric lock  50 , detect the closure of the doors via the sensor  170  and control the contents of the display  145 . 
     The electronic circuits  115  are also adapted to unlock the electric lock  150  when the emergency opening button  175  is pressed. 
     The operation of the electronic circuits  115  is detailed with reference to  FIG. 7 . 
     The electric lock  150  is of known type. It is used to lock the doors  130 . The communication means  155  allows remote communication with a computer, a server or a information processing system comprising a network, according to known techniques, on wired or wireless support. The communication means  155  may comprise, for example, a modem. 
     The identification card  135  reader  140  is, for example, of type known in the field of radio frequency identification. In this case, each card  140  comprises a transponder, or electronic tag and the reader  135  comprises an antenna for transmission and reception of magnetic fields, which are modulated so as to exchange data required to identify the cards  140 . 
     As a variant, the reader  135  may be replaced by a biometric identification device of known type, to identify the users accessing the content of the rack  100 . 
     The display  145  is of known type, for example a Liquid Crystal Display (LCD screen) and used to display visible messages to users, for example instructions for their identification, for the positioning of products  125  in the rack  100  and to display warnings if the number of products of a given reference reaches a predetermined value or if one of the products is approaching its use-by-date. 
     The door closure sensor  170  is of known type, for example dry contact or Hall effect type. It is preferably incorporated in the electric lock  150 . 
     Preferably, when the back wall supports an antenna, arrangements are made so that the electronic tags cannot be placed in the immediate vicinity of this antenna. For example, the back wall in front of each antenna is made slightly thicker, projecting into the rack. 
       FIG. 2  shows, in a rack  200 , the same elements as in  FIG. 1 , the shelves and the products not being shown for clarity reasons, as well as an antenna  205 , in or on the back wall  105  of the rack  200 , and antennas  210 ,  215 ,  220 ,  225 ,  230  and  235 , placed two by two in or on the side walls  240  and  245  and central wall  250  of the rack  200 . In this case, the electronic circuits  115  are adapted to multiplex the uses of the antennas to successively query the electronic tags  160  whose antennas are positioned according to orthogonal axes. 
       FIG. 3  shows that a first shape of antenna  300  incorporated in a rack illustrated in  FIG. 1  or  2  consists of a figure-8, i.e. two coplanar loops  305  and  310 , the conductor forming this antenna going alternately through one or the other of the two loops, with opposite directions of rotation. In this figure, only one coil has been represented, it being understood that the antenna actually comprises a large number of superimposed coils. 
     Consequently, when the current flows through the two coplanar loops, in one of the loops it flows in the clockwise direction and, simultaneously, in the other loop it flows in the anticlockwise direction. This configuration generates an electromagnetic field over an extended volume near the back wall  105  of the rack. 
       FIG. 4  shows that a second shape of antenna  400  incorporated in a rack illustrated in  FIG. 1  or  2  consists of three coplanar loops  405 ,  410  and  415 , the conductor forming this antenna going alternately through the three loops, with directions of rotation alternately clockwise and anticlockwise. In this figure, only one coil has been represented, it being understood that the antenna actually comprises a large number of superimposed coils. 
     Consequently, when the current flows through the three coplanar loops, in at least one of the loops it flows in the clockwise direction and, simultaneously, in at least one other loop it flows in the anticlockwise direction. This configuration generates an electromagnetic field over an extended volume near the back wall  105  of the rack. 
       FIG. 5  shows that a third shape of antenna  500  incorporated in a rack illustrated in  FIG. 1  or  2  consists of four coplanar loops  505 ,  510 ,  515  and  520 , the conductor forming this antenna going alternately through the four loops, with directions of rotation alternately clockwise and anticlockwise. In this figure, only one coil has been represented, it being understood that the antenna actually comprises a large number of superimposed coils. 
     Consequently, when the current flows through the four coplanar loops, in two of these loops it flows in the clockwise direction and, simultaneously, in the other two loops it flows in the anticlockwise direction. This configuration generates an electromagnetic field over an extended volume near the back wall  105  of the rack. 
     In the case of the rack illustrated in  FIG. 2 , for example, the back wall supports both an antenna as illustrated in  FIG. 3  and an antenna as illustrated in  FIG. 4  and each side or central wall supports an antenna as illustrated in  FIG. 3 . The inventors discovered, in fact, that this configuration covered the entire interior volume of the rack  200  without leaving any dead areas, with the electromagnetic fields successively transmitted by the various antennas. 
       FIG. 6  shows a product  125  comprising a paper label  165  and the electronic tag  160 . The product comprises a metallic part  610  (in this case a metallic or metalized bag) which is thin, in other words of thickness less than one quarter of its largest dimension, on at least one of its edges  605 . The electronic tag  160  has an antenna  615  which is positioned substantially perpendicular to a thin edge of the metallic part  610 . 
     The antenna  615  preferably has a width, measured in the direction of the thickness of the metallic part  610 , greater than the thickness of the edge  605  of the metallic part opposite which the antenna is positioned. 
     The inventors have discovered that, with these characteristics, the electronic tag could be read despite the proximity of the metallic part and the electronic tag. 
     In  FIG. 6 , the product  125  has the shape of a rectangular parallelepiped and comprises the electronic tag on one of its four smallest sides. The product  125  also comprises a paper label  165  positioned on a side of the product opposite the side of the product bearing said electronic tag. In this case, the paper label  165  shows the reference “duo M8H”. 
     As a variant, the paper label  165  is positioned on one side of the product adjacent to a side of the product bearing said electronic tag  160  on one of its small sides. 
     Consequently, when the user stores the product  125 , in a stack or vertically in the rack  100  or  200 , he is encouraged to position it so that its paper label  165  is visible. Due to this position, the electronic tag  160  is positioned towards the back wall of the rack or towards one of its shelves, allowing the electronic tags  165  to be read by an antenna positioned on or in the back wall or a shelf, respectively. 
     The inventors discovered, in fact, that with this configuration: 
     the user could read the text shown on the paper label  165 , without moving the product  125 , when the rack doors  130  are open or through these doors  130  when they are transparent, and 
     the electronic tags  160  were positioned near to and opposite the antenna supported by the back wall  105  of the rack. 
     When the product  125  is flat, for example with a thickness of 10 mm to 12 mm, the electronic tag  160  preferably comprises an elongated antenna  615 , for example measuring 8 mm×80 mm. 
     As show in  FIG. 7 , an initialization step  702  is first carried out, during which associations are defined between:
         electronic tag identifiers and product references,   electronic tag identifiers and product use-by-dates,   minimum numbers of products of each reference below which products with this reference must be reordered and   card identifications with user identifications.       

     This step  702  can be carried out by reading data in a local and/or remote database, as indicated with reference to  FIG. 9 . 
     The rack circuits then perform a first read of the electronic tags present in the rack by successively generating magnetic fields on the various sets of antennas incorporated in the rack, step  704 , associate them with product references, step  706 , transmit this information remotely, step  708 , and go into standby while leaving the identification card  140  reader  135  switched on and displaying, on the display, the rack use instructions. 
     When a user comes to open the rack, he is identified, step  710 , his identifier is stored, step  712 , and the rack lock is unlocked, step  714 . 
     When the rack door closure sensor indicates that the doors are closed, step  716 , the lock is locked, step  718 , and the time which has elapsed since the doors were closed is measured, step  720 . 
     When this duration reaches a first predetermined value, for example ten seconds, step  722 , the electronic tags of the products present in the rack are read, step  724 , by successively using the rack antennas. 
     When the time which has elapsed since the rack was closed reaches a second predetermined value, for example one minute, step  726 , the electronic tags of the products present in the rack are read, step  728 , by successively using the rack antennas. 
     The list of identifiers obtained during steps  724  and  728  are then compared and, if they are different, additional reads of the electronic tag identifiers are carried out, at predetermined time intervals, for example one minute between two reads, until three successive reads give the same list, step  730 . 
     The electronic tag identifiers are then associated with product references, step  732 , and this information is transmitted remotely, step  734 . 
     The list of products present is then compared with the list of products previously present, step  736 , and the identification of the user who opened the rack is associated with the references and identifiers of the products which have been added to or removed from the rack, step  738 , and this information is transmitted remotely, step  740 . 
     During a step  742 , a check is then carried out to determine, for one or more product references, whether the number of products present in the rack is less than or equal to a predetermined value. If yes, during a step  744 , a local warning is triggered, this information is transmitted remotely and the references of the missing products are shown on the display. 
     Then, if the result of step  742  is negative or after step  744 , during a step  746 , a check is carried out to determine whether the use-by-date of at least one product present in the rack lies within a future of predetermined duration, for example one month. If yes, during a step  748 , a local warning is triggered, this information is transmitted remotely and the references of the products concerned are shown on the display. 
     Then, if the result of step  746  is negative or after step  748 , the rack circuits go into standby while leaving the identification card  140  reader  135  switched on and displaying, on the display, the rack use instructions, before returning to step  710 . 
       FIG. 8  shows a information processing system  800  comprising a plurality of racks  802  to  810 , as illustrated in  FIG. 1  or  2  and connected together and to local workstations  815 ,  820  and  825 , by local networks respectively  830 ,  835  and  840 , a server  845  connected to said local networks, by an external network  850  and external workstations  855  and  860  connected, via the external network  850 , to the server  845 . 
     The workstations  815 ,  820 ,  825 ,  855  and  860 , as well as the server  845  are of known type and each comprises a microprocessor and communication means, for example a modem, enabling them to communicate with the networks to which they are directly connected. 
     The local workstations implement several user interfaces. A first user interface is used to display the inventory of products present in the various racks of the product user center and, possibly, to launch a read of all the tags on the products present in the rack to check the inventory, for example before a medical operation. This user interface can also be used to access the history of previous inventories. 
     A second user interface is used to manage automatic renewals and transmit them to the server which forwards them to the suppliers concerned. This restocking can be carried out at fixed times, for example at the end of the working day to avoid renewing a product which is put back in a rack after having been removed, for example in preparation for surgery. 
     A third user interface is used to assign a complex meaning to an identification card, for example assignment of the products which will be taken from a rack with this card in a specific time interval, to an operating theatre, a patient, a user or a doctor. This assignment allows management of the products consumed during an operation and their invoicing, it being understood that the products put back later into one of the racks, identified by their electronic tags, are recredited to the stock of products. 
     The external network  850  is, for example, the Internet. 
     In addition, the server  845  comprises a database  875 , means of selective access  880  to the database by the workstations  815 ,  820 ,  825 ,  855  and  860 , a warning computer program  890  and a monitoring computer program  895 . 
     The database  875  contains information concerning the products contained in the racks  802  to  810 . 
     The workstations  855  and  860  are implemented by suppliers of products likely to be stored in racks, preferably equipped with paper labels and electronic tags placed on opposite sides of these products. 
     The workstation  815  and the racks  802  and  804  are located in a first product user center and contain products from suppliers implementing the workstations  855  and  860 . 
     The workstation  820  and the racks  806  and  808  are located in a second product user center and contain products from suppliers implementing the workstations  855  and  860 . 
     The workstation  825  and the rack  810  are located in a third user center and contain products from suppliers implementing the workstations  855  and  860 . 
     The means of selective access  880  to the database are of known type, for example authentication software (for example with user name and password or with card or biometric recognition) or signature software and are adapted to allow each product user center to access its own stock of products contained in the racks  802  to  810 , irrespective of the product suppliers. 
     The means of selective access  880  are also adapted to allow each supplier to access, for all product user centers, the stock level, in the racks  802  to  810 , of its own products. 
     The warning computer program  890  is adapted to trigger warnings when a minimum number of products of a particular reference has been reached in the stock of a product user center. This warning can be used to increase the number of products to be renewed to avoid further warnings. 
     The monitoring computer program  895  is used to produce a sales report for each supplier, giving a summary of the references by product user center and/or by territory. 
     Since each workstation of a product user center can be connected by the Internet to the server  845 , it can be identified and receive information concerning the products in stock, i.e. entering a rack or leaving a rack in the product user center concerned. Each workstation of a product user center can also consult the delivery delays for the products stored in order to manage their renewal. 
     As shown on  FIG. 9 , an initialization step  902  is carried out to initialize the various computer devices, during which the database of the product references and suppliers, and the means of authenticating the users and/or the various workstations likely to access the database, are created. 
     Then, during a step  904 , each rack supplies a first list of products it contains, this list being automatically renewed each time the doors of these racks are closed and completed by warnings and user identifications, as explained previously. 
     During a step  906 , the server aggregates the data received by product user center, by supplier and by user. 
     During a step  908 , the server determines whether a request to access the database has been received. If not, return to step  904 . If the result of step  908  is positive, during a step  910 , the user and/or the workstation attempting to access the database are identified. 
     If the identification fails, return to step  904 . If the identification succeeds, during a step  912 , a check is carried out to determine whether the user and/or the workstation attempting to access the database is a product user center workstation or a supplier workstation. 
     If it is a product user center, access is allowed to all its own stock of products contained in the racks of this product user center, irrespective of the product suppliers, step  914 . 
     It is also allowed, step  916 , to renew products with the suppliers, in which case the renewal request is sent to the suppliers concerned. The product user center therefore selects, in the database, the product references and quantities to renew the stock, the renewal forms being automatically distributed between the suppliers of the references concerned. 
     If, during step  912 , a supplier is found to be accessing, during a step  918 , this supplier is allowed to access, simultaneously for all the product user centers, the stock level, in said racks, of its own products. 
     The supplier is also allowed, step  920 , to update its product references, prices and delivery delays and to consult the renewal forms sent to it. The server can therefore be used to produce a sales report for each supplier, giving a summary of the references by product user center and/or by territory, according to known techniques. 
     After step  916  or  920 , a check is carried out to determine whether a warning has been received from a rack, step  922 , and, if yes, this warning is transferred to the workstation of the product user center concerned, step  924 . Then, if the result of step  922  is negative or after step  924 , return to step  904 . 
     As can be seen from the above example, there is a significant improvement over the existing techniques by providing an installation which can be used to manage simply and efficiently the stock of medical equipment in the product user centers and to manage the flow of equipment between the suppliers and these product user centers while allowing the suppliers to manage their stock stored in each product user center. This equipment may be disposable equipment or equipment that can be recycled, in particular equipment used for the fitting of some prostheses.