Abstract:
An inventory-tracking unit associated with a storage unit holding items to be dispensed includes a card reader to read an access card issued to a user and a recorder to record data from items removed from the storage unit. A processor communicates with a sensor in the storage unit and with the card reader and recorder. The sensor provides item data to the processor that is associated with items removed from the storage unit. The processor compares item data received from the sensor with the data recorded by the recorder to detect coincidence. The processor generates a transaction upon coincidence of item data received from the sensor with the recorded data. A communications interface transmits the transaction to a remote site.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates generally to inventory management and in particular to a system and method for tracking inventory and to an inventory-tracking unit.  
       BACKGROUND OF THE INVENTION  
       [0002]     Inventory control is a primary concern for product retailers so that excess and insufficient inventory situations are avoided. Within a mortar and bricks environment, inventory is controlled by counting existing inventory at physical locations. Controlling inventory in this manner is however much more difficult and in fact impractical in environments where inventory is dispensed through stocked vending machines that are distributed over a large geographical area.  
         [0003]     To deal with inventory control in these environments, service personnel are dispatched along service routes according to pre-set schedules so that the vending machines can be checked for inventory levels and proper operation. As will be appreciated, during a service route all vending machines along the service route are checked. In many instances, the checks reveal that the vending machines are operating properly and hold sufficient inventory. As a result, the checks are unnecessary. In other instances, the checks reveal that the vending machines have malfunctioned and/or are depleted of inventory, resulting in potential lost sales especially if delays exist between checks.  
         [0004]     A similar problem exists in the medical supply environment where medical, surgical, biological and/or pharmaceutical supplies are stored in refrigeration units distributed throughout medical, research and/or educational facilities located at different geographical locations. In the past, dispatching medical supplies through these refrigeration units has been based on the honor system. Users removing supplies from refrigeration units are expected to list the removed supplies on charts posted on the refrigeration units so that supply usage can be tracked and costs assigned in the appropriate manner.  
         [0005]     As will be appreciated, inventory control in this medical supply environment suffers similar problems to those encountered in the vending machine environment discussed above. Routine checks of all refrigeration units must be carried out to determine the inventory level and operating status of the refrigeration units. In many cases the checks are either unnecessary or late. The latter condition can be particularly problematic in the case where a refrigeration unit fails and the temperature within the refrigeration unit rises to a point where the inventory is spoiled. Inventory shrinkage is also a problem in the medical supply environment. In many instances, users removing supplies from the refrigeration units fail to record accurately the removed items. As a result, costs for the missing inventory cannot be assigned. As will be appreciated, improvements in inventory control in these types of environments are desired.  
         [0006]     It is therefore an object of the present invention to provide a novel system and method for tracking inventory and a novel inventory-tracking unit.  
       SUMMARY OF THE INVENTION  
       [0007]     According to one aspect of the present invention there is provided an inventory-tracking unit associated with a storage unit holding items to be dispensed comprising: 
        a card reader to read an access card issued to a user;     a recorder to record data from items removed from said storage unit;     a processor communicating with a sensor in said storage unit and with said card reader and recorder, said sensor providing item data to said processor that is associated with items removed from said storage unit, said processor comparing item data received from said sensor with data recorded by said recorder to detect coincidence, said processor generating a transaction upon coincidence of item data received from said sensor with said recorded data; and     a communications interface to transmit said transaction to a remote site.        
 
         [0012]     In one embodiment, the communications interface transmits the transaction over a wireless communications link, the recorder is a barcode scanner, the card reader is designed to read a magnetic stripe on an access card and the storage unit is a refrigeration unit. A housing accommodates the card reader, barcode scanner, processor and communications interface. The housing is coupled to the storage unit and the processor is wired to the sensor. During access of the storage unit, the card reader locks the access card therein until the item data received from the sensor is coincident with the recorded data.  
         [0013]     In one embodiment, the inventory-tracking unit further comprising a locking mechanism coupled to the storage unit to inhibit access to items held therein. The locking mechanism is conditioned by the processor to a disengaged state to permit access to items held in the storage unit when a valid access card is read by the card reader. The processor communicates with at least one diagnostic sensor associated with the storage unit and transmits an alarm event to the remote site in response to alarm condition input received from the at least one diagnostic sensor.  
         [0014]     According to another aspect of the present invention there is provided an inventory-tracking system comprising: 
        a remote site; and     at least one inventory-tracking unit associated with storage unit holding items to be sensed, said inventory-tracking unit comprising: 
            an inventory-tracking unit associated with a storage unit holding items to be dispensed comprising:     a card reader to read an access card issued to a user;     a recorder to record data from items removed from said storage unit;     a processor communicating with a sensor in said storage unit and with said card reader and scanner, said sensor providing item data to said processor that is associated with items removed from said storage unit, said processor comparing item data received from said sensor with data recorded by said recorder to detect coincidence, said processor generating a transaction upon coincidence of item data received from said sensor with said recorded data; and     a communications interface to transmit said transaction to a remote site.    
               
 
         [0022]     The present invention provides advantages in that the inventory-tracking unit can be easily retrofitted to existing refrigeration units thereby to permit existing refrigeration units to be upgraded so that inventory therein can be remotely monitored and tracked over a wireless communications link. Since the inventory-tracking unit controls access to the inventory within the refrigeration unit, distribution of restricted inventory can be accurately controlled thereby to inhibit inventory loss through inventory expiry and/or shrinkage.  
         [0023]     The present invention also provides advantages in that since inventory removed from the refrigeration unit is tracked in real time, inventory within the refrigeration unit can be managed to avoid item “sell-out” conditions. Statistical information concerning inventory use can also be easily generated allowing inventory stocking procedures to be adjusted to meet inventory demand. In addition, if the refrigeration unit suffers a failure and the temperature within the refrigeration unit rises above a threshold temperature, since the operating state of the refrigeration unit is remotely monitored service personnel can be dispatched quickly to avoid inventory spoilage. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]     Embodiments of the present invention will now be described more fully with reference to the accompanying drawings in which:  
         [0025]      FIG. 1  is a front elevation view of a refrigeration unit in combination with an inventory-tracking unit in accordance with the present invention;  
         [0026]      FIG. 2  is a front elevation view of the inventory-tracking unit of  FIG. 1 ;  
         [0027]      FIG. 3  is a left side elevation view of the inventory-tracking unit of  FIG. 1 ;  
         [0028]      FIG. 4  is a right side elevation view of the inventory-tracking unit of  FIG. 1 ;  
         [0029]      FIG. 5  is a rear elevation view of the inventory-tracking unit of  FIG. 1 ;  
         [0030]      FIG. 6  is a top plan view of the inventory-tracking unit of  FIG. 1 ;  
         [0031]      FIG. 7  is a front elevation view of the interior of the inventory-tracking unit of  FIG. 1 ;  
         [0032]      FIG. 8  is a block diagram of internal circuitry within the inventory-tracking unit of  FIG. 1 ;  
         [0033]      FIG. 9  is a flowchart showing the steps performed by the inventory-tracking unit during accessing of the refrigeration unit;  
         [0034]      FIG. 10  is a schematic view of an inventory-tracking system including an inventory-tracking unit that communicates with a remote site over a wireless wide area network;  
         [0035]      FIG. 11  is a front elevation view of a refrigeration unit in combination with a top mounted inventory-tracking unit; and  
         [0036]      FIG. 12  is a schematic view of an inventory-tracking system including inventory-tracking units that communicate with a computer room over a wireless local area network. 
     
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS  
       [0037]     Turning now to  FIG. 1 , a refrigeration unit such as a freezer in which medical, surgical, biological and/or pharmaceutical supplies (hereinafter referred to as “medical supplies”) are stored, is shown and is generally identified by reference numeral  20 . An inventory-tracking unit  30  is coupled to one side of the refrigeration unit  20  to track inventory removed from the refrigeration unit. The inventory-tracking unit  30  may alternatively be mounted on the top of the refrigeration unit  20  as shown in  FIG. 11 .  
         [0038]     The refrigeration unit  20  for the most part is standard and receives power from a conventional 120 volt AC power source via an electrical cord. A door light switch is provided in the refrigeration unit  20  to sense when the door of the refrigeration unit is in an open or closed condition. As is known, when the door of the refrigeration unit  20  is opened, the door light switch closes a circuit causing an internal light within the refrigeration unit  20  to illuminate. An internal sensor antenna of the acoustic or electromagnetic type (not shown) is accommodated within the rubber seal surrounding the door frame of the refrigeration unit  20  to sense tagged items being placed in or removed from the refrigeration unit. A temperature sensor in the form of a thermistor is also provided in the refrigeration unit  20  to sense when the temperature within the refrigeration unit  20  rises above a threshold temperature.  
         [0039]     FIGS.  2  to  6  better illustrate the physical layout of the inventory-tracking unit  30 . As can be seen inventory-tracking unit  30  includes a housing  32  that is secured to the side of the refrigeration unit  20  by a plurality of suitable fasteners (not shown). The front face of the housing includes a barcode scanner or reader  34 , a display  36  and a card reader  38 . A spring-loaded solenoid door lock  40  is also provided on the front face of the housing  32  and is actuable to engage and disengage the door of the refrigeration unit to control entry into the refrigeration unit  20 . An antenna  42  is provided on one side of the housing  32  to allow the inventory-tracking unit  30  to communicate with a remote site over a wireless communication link as will be described. Ventilation holes  44  are provided in the top of the housing  32  to allow air to circulate within the housing  32  thereby to dissipate heat.  
         [0040]     Turning now to  FIG. 7 , the integrated internal physical layout of the inventory-tracking device  30  is illustrated. The inventory-tracking device  30  includes a main control board  50  that communicates with the barcode scanner  34 , the display  36 , the card reader  38  and the solenoid door lock  40 . The main control board  50  also communicates with a modem  52  that is coupled to the antenna  42  as well as with a multi-drop bus (MDB) board  54 . An audio siren  56  is also coupled to the main control board  50 .  
         [0041]     The circuitry on the main control board  50  and the multi-drop bus board  54  is illustrated in  FIG. 8  and is generally identified by reference numeral  60 . As can be seen, circuitry  60  includes a central processing unit (CPU)  62  having a real-time clock. CPU  62  communicates with a microprocessor supervisor  64  and with a plurality of interfaces via a databus  66 , namely a card reader interface  68 , a radio interface  70 , and a freezer interface  72 . Card reader interface  68  is coupled to the card reader  38 . Radio interface  70  is coupled to a wide area network (WAN) radio transceiver  74  and/or to a local area network (LAN) radio transceiver  76 . The transceivers  74  and  76  communicate with the antenna  42  thereby to permit wireless communications. The freezer interface  72  is coupled to the solenoid door lock  40 .  
         [0042]     CPU  62  further communicates with static random access memory (RAM)  80 , flash memory  82  and communications interface  84  via the databus  66 . The communications interface  84  communicates with the internal sensor antenna within the refrigeration unit  20 . The display  36  is also coupled to the databus  66  and communicates with the CPU  62 . An on-board power supply  86  provides the necessary power for operation of the inventory-tracking unit  30 . On-board power supply  86  is coupled to the electrical cord of the refrigeration unit  20  via an interconnecting harness (not shown). CPU  62  also receives conductors coupled to the door light switch within the refrigeration unit  20  via the interconnecting harness allowing a time stamp to be generated when the door of the refrigeration unit  20  is opened and then closed.  
         [0043]     The operation of the inventory-tracking unit  30  will now be described with particular reference to  FIG. 9 . When a user wishes to gain access to the refrigeration unit  20 , the user inserts their access card into the card reader  38 . When the card reader  38  detects the inserted card (step  202 ), the magnetic stripe on the access card is read (step  204 ) and the read card data is conveyed to the CPU  62  via the databus  66 . The CPU  66  in turn compares the read card data with a list of authorized users to determine if the card is valid (step  206 ). If the read card data is determined to be invalid, the user is denied access to the refrigeration unit  20 . The access card is ejected from the card reader  38  (step  208 ) and the card reader returns to a ready state waiting for another access card to be inserted therein (step  200 ). At step  206 , if the read card data is determined to be valid, the CPU  62  signals the card reader  38  to lock the access card therein (step  210 ). The CPU  62  also signals the solenoid door lock  40  via the freezer interface  72  causing the solenoid door lock to disengage the door of the refrigeration unit  20  (step  212 ). With the door of the refrigeration unit  20  unlocked, the user is able to open the refrigeration unit  20  thereby to gain access to supplies therein.  
         [0044]     When the user opens the door of the refrigeration unit and the door light switch closes the circuit to illuminate the interior light within the refrigeration unit  20 , a signal is conveyed to the CPU  62 . The CPU  62  in turn generates a time stamp using the real-time clock allowing the time the refrigeration unit  20  is in an open condition to be accurately tracked. As the user begins removing items from the refrigeration unit  20 , the tag on each removed item is detected by the internal sensor antenna. The internal sensor antenna in turn signals the CPU  62  via the communications interface  84  and databus  66  allowing the CPU  62  to maintain a count of the removed items (step  222 ).  
         [0045]     When the door of the refrigeration unit  20  is closed, the CPU  62  conditions the barcode scanner  34  to a ready state and ends the time stamp (step  224 ). As a result, the length of time each user maintains the refrigeration unit  20  opened can be monitored. Extended door open conditions that may cause undesired temperature changes within the refrigeration unit  20  can also be detected. With the barcode scanner  34  enabled, the user is required to pass the removed items beneath the barcode scanner  34  so that the barcodes on the removed items can be scanned. After each barcode is scanned, the barcode scanner  34  conveys the scanned barcodes to the CPU  62  allowing the CPU  62  to maintain a list of the scanned items (step  226 ). When the number of scanned items is equal to the removed item count, the CPU  62  signals the solenoid door lock  40  via the freezer interface  72  causing the solenoid door lock  40  to engage the door of the refrigeration unit  20  (step  230 ). The access card is then ejected from the card reader  38  (step  208 ) and the card reader returns to a ready state waiting for another access card to be inserted therein (step  200 ). As will be appreciated, since a count of removed items is maintained and compared with the list of scanned barcodes, accurate transactions involving inventory within the refrigeration unit  20  can be maintained.  
         [0046]     After a user has completed a transaction with the refrigeration unit  20 , the CPU  62  conveys the scanned barcode information to a remote site over a wireless communication link via the radio interface  70  and one of the transceivers  74  or  76 . In the scenario shown in  FIG. 10 , the inventory-tracking unit  30  conveys the transaction to a remote site  100  over a wireless wide area network  102  via radio interface  70  and WAN transceiver  74 . In the scenario shown in  FIG. 12 , inventory-tracking units  30  convey transactions to a computer room  104  over a wireless local area network  106  via radio interfaces  70  and LAN transceivers  76 .  
         [0047]     At the remote site, the received scanned barcode data is stored in a database so that an accurate real-time status of the inventory within the refrigeration unit  20  can be maintained. The maintenance of accurate inventory information allows useful sales reports to be generated and allows replenishment schedules to be adjusted to conform to inventory demand. Generated reports are posted on encrypted web pages that can be accessed by authorized users via Internet connections.  
         [0048]     Depending on the environment, the scanned barcode data may be used to debit an account associated with the user. In this case, when the debit value of the account reaches a threshold level, the remote site generates a request for funds to zero the debit value. In this manner, the access card functions as both an access and debit card i.e. similar to a smart card.  
         [0049]     If at any time, the temperature within the refrigeration unit rises above the threshold temperature as detected by the thermistor, the internal sensor antenna in the refrigeration unit  20  signals the inventory-tracking unit  30 . In response, the CPU  62  generates an alarm signal that is used to sound siren  56  and records the alarm event. The CPU  62  also conveys the alarm event to the remote site over the wireless communications link so that the alarm event can be recorded. The CPU  62  also generates and records an alarm event when the door of the refrigeration unit  20  is left open for an extended period of time above a threshold and when the compressor of the refrigeration unit is believed to be approaching its service life. These alarm events are also recorded and conveyed to the remote site over the wireless communications link. In this manner service personnel can be quickly dispatched.  
         [0050]     If desired, since the internal sensor antenna detects when items are placed into the refrigeration unit  20 , the inventory-tracking unit  30  can be programmed to maintain an item count during restocking and convey the item count to the remote site providing for complete inventory control.  
         [0051]      FIGS. 1 and 11  show a small number of inventory-tracking units  30  communicating with a remote site. Those of skill in the art will appreciate that this is for illustrative purposes only. In a typical environment, the remote site recieves transactions from a significant number of geographically distributed inventory-tracking units  30 . Also, the inventory-tracking units may be used with other types of storage units such as for example vending machines and the like. In the case of vending machines that securely hold items, the requirement for a door locking mechanism is obviated.  
         [0052]     Although embodiments of the present invention have been described, those of skill in the art will appreciate that variations and modifications may be made without departing from the spirit and scope thereof as defined by the appended claims.