Abstract:
An indicator circuit for a storage container designed to enable remote electronic searching for file folders located within the container. Address signals from a host computer are supplied to the storage container to designate a sought file folder. The indicator circuit is activated whenever a sought file folder is located in a given container. When two or more storage containers are interconnected to receive address signals designating a sought file folder, only the indicator circuit of the storage container containing the sought file folder is activated.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates in general to storage containers designed to enable remote electronic searching for objects located within the containers. More particularly, this invention relates to an indicator circuit for such storage containers which is activated whenever a sought object is located in a given container. 
     Some known storage containers are constructed according to a unique design for enabling remote electronic searching for objects, such as file folders and documents within such file folders, located somewhere within a collection of electrically interconnected storage containers. Commonly assigned pending U.S. patent application Ser. No. 13/694,829 filed Jan. 8, 2013 for “Storage Container For Electronically Addressable File Folders And Documents”, now U.S. Pat. No. 8,963,716 issued Feb. 24, 2015, the disclosure of which is hereby incorporated by reference, discloses such a container design. With reference to  FIG. 1 , each container  10  is provided with a pair of electrically conductive support rails  17 ,  18  mounted in the container  10  interior near the top margin. The rails  17 ,  18  are laterally spaced by an amount designed to receive the ends of support braces  21 ,  22  incorporated into file folders  20  (only one illustrated in  FIG. 1  for clarity) removably placed within the container  10  to provide both mechanical support for each file folder  20  and electrical connections to circuitry including an address decoder located within one of the file folder  20  support braces  21 ,  22  (as illustrated, support brace  21 ). The circuitry in support brace  21  also includes a pair of visible indicators: a POWER ON indicator  23 , and an ADDRESS MATCH indicator  24  (each preferably an LED). The circuitry in support brace  21  is described and illustrated in commonly-assigned, co-pending U.S. patent application Ser. No. 12/803,712 filed Jul. 2, 2010 for “Documents Management Using Remote Document Location And Retrieval ”, now U.S. Pat. No. 8,994,534 issued Mar. 31, 2015, the disclosure of which is hereby incorporated by reference. 
     A container circuit board (not illustrated in  FIG. 1 ) is mounted in the container  10  and contains electronic circuitry for receiving unique address signals supplied by a host computer via a local controller which identify a folder or document to be located. The rails  17 ,  18  are individually coupled to the electronic circuitry on the container circuit board: one of the rails (rail  17 ) receives the address signals from the local controller and supplies them to all file folders  20  residing in the container  10 ; and furnishes response signals from the file folders to the electronic circuitry of the container circuit board. These response signals are coupled to the local controller, which sends the information contained in the signals to the host computer. The information in the response signals includes the identification of the storage container in which the found folder is located. Visible POWER ON indicator  23  on file folder  20  is activated whenever the folder brace  21  is ohmically connected to rails  17 ,  18  in order to signify that the file folder  20  is installed correctly and is operable. Indicator  23  is preferably an LED having a relatively low current draw when activated of no more than about 0.3 mA. Visible ADDRESS MATCH indicator  24  is activated whenever the address stored in the circuitry in folder brace  21  matches the folder address supplied to the file folder circuitry by the local controller via rail  17 . Indicator  24  is preferably an LED having a substantially larger current draw of about 15.0 mA when activated 
     Each container  10  also has a visible indicator  25  mounted on a wall (such as wall  12 ) in a position visible to a human operator standing within viewing distance of the storage container  10 . Indicator  25  is coupled to the electronic circuitry on the container circuit board and is illuminated whenever the address signals supplied by the host computer specify a file folder or document located in that container  10 . An input connector  32  and an output connector  33  are mounted on one of the walls of container  10 , such as wall  12 : the input connector  32  receives the address signals from the host computer via the local controller; the output connector  33  couples address signals from one container  10  to another container and returns search result information from any container to the local controller. The local controller sends this information to the host computer. 
       FIG. 2  illustrates a stacked array of such storage containers. As seen in this Fig., a plurality of storage containers  10 - 1 ,  10 - 2 , . . . ,  10 - n are stacked in a vertical array. Each container  10 -I has an input connector  32 - 1 ,  32 - 2 , . . . ,  32 - n ; and an output connector  33 - 1 ,  33 - 2 , . . . ,  33 - n . A local controller  45  receives address signals from a remote host computer (not shown) and supplies these signals to one of the containers  10 - 1  by means of an input cable  46  and input connector  32 - 1  of container  10 - 1 . The address input signals are coupled to the remaining containers in the stack by means of jumper cables  34 - 1 ,  34 - 2 , . . . ,  34 - n - 1  which are individually connected between the output connector  33 -I of one container  10 -I and the input connector  32 -I of the next container  10 -I. In a preferred embodiment, connectors  32 -I,  33 -I and cables  34 -I and  46  are standard USB devices. 
     The arrangement of  FIG. 2  has no provision for uniquely illuminating the visible indicator  25 -I of the container  10 -I in which the file folder  20  having the correct sought address is located. This does not pose a problem when only one container  10  is connected to the local controller  45 . However, when a plurality of storage containers  10 -I of the type described are interconnected as shown in  FIG. 2  and one of the containers holds the sought file folder, the visible indicators  25 -I of all of the storage containers  10 -I are activated. This requires a human operator to visually inspect the interior of each storage container  10 -I in the stack until the file folder having the activated ADDRESS MATCH LED  24  is located, which unduly prolongs the search process. 
     SUMMARY OF THE INVENTION 
     The invention comprises an indicator circuit for storage containers of the type described above which ensures that only the indicator of the storage container in which the sought file folder having the matching address is activated, while the rest of the container indicators in the interconnected array of storage containers remain unactivated. 
     In a broadest aspect, the invention comprises the improvement in a storage container having circuitry for enabling remote location and retrieval of documents located in file folders operationally installed within said storage container, the storage container including a base wall; a plurality of upstanding wall members connected to the base wall, the base wall and the plurality of upstanding wall members defining an enclosure volume; first and second electrically conductive support members each secured to at least one of the wall members in an essentially parallel and mutually spaced manner, the spacing between the first and second support members being sufficient to accommodate the ends of a file folder in mechanically supportive fashion; an electrical input connector secured to one of the upstanding wall members and ohmically coupled to the first and second support members for providing file folder address signals supplied by a source to at least one of the first and second support members, so that the file folder address signals are coupled to any file folder supported by the support members; and a storage container indicator; the improvement comprising an indicator control circuit for activating the storage container indicator when a file folder operationally installed on the first and second electrically conductive support members has an address matching the file folder address signals and the storage container is electrically coupled to another storage container. 
     The indicator control circuit preferably includes a fixed resistance coupled between the input connector and one of the first and second electrically conductive support members, means for sensing the voltage value at the junction of the fixed resistance and that one of the first and second electrically conductive support members, the sensing means having an input coupled to the junction and an output, and a control unit having an input coupled to the output of the sensing means and an output coupled to the storage container indicator for activating the storage container indicator when the voltage value reaches a threshold value. 
     The storage container indicator preferably comprises a light source, most preferably an LED, mounted to one of the wall members in a location visible from the exterior of the container. 
     The sensing means preferably comprises an operational amplifier and the control unit preferably comprises a microcontroller. 
     The storage container also includes an electrical output connector secured to one of the upstanding wall members and coupled to the input connector for manifesting the file folder search signals supplied by the source to at least one of the first and second support members, so that the file folder search signals can be coupled to support members located in another document storage container having an electrical input connector coupled to the electrical output connector. 
     In another aspect, the invention comprises an array of portable document storage containers for enabling remote location and retrieval of documents located in file folders received with the storage containers. The array comprises a plurality of document storage containers each having a base wall; a plurality of upstanding wall members connected to the base wall, the base wall and the plurality of upstanding wall members defining an enclosure volume; first and second electrically conductive support members each secured to at least one of the wall members in an essentially parallel and mutually spaced manner, the spacing between the first and second support members being sufficient to accommodate the ends of a file folder in mechanically supportive fashion; an electrical input connector secured to one of the upstanding wall members and ohmically coupled to the first and second support members for providing file folder address signals supplied by a source to at least one of the first and second support members, an electrical output connector secured to one of the upstanding wall members and ohmically coupled to the electrical input connector, the output connector of some (preferably all) of the document storage containers being coupled to the input connectors of other ones of the document storage containers to form an electrically intercoupled array so that the file folder address signals are coupled to any file folder supported by the support members in all of the storage containers in the intercoupled array; a storage container indicator; and an indicator control circuit for activating the storage container indicator in the storage container when a file folder operationally installed on the first and second electrically conductive support members has an address matching the file folder address signals; and 
     a controller having an output coupled to the input connector of one of the plurality of document storage containers for providing file folder search signals supplied by a source to at least one of the first and second support members of the document storage container connected thereto, the file folder search signals being coupled to all of the document storage containers in the electrically intercoupled array so that the file folder search signals are coupled to any file folder supported by the support members in any of the document storage containers in the intercoupled array. 
     The indicator control circuit preferably includes a fixed resistance coupled between the input connector and one of the first and second electrically conductive support members, means for sensing the voltage value at the junction of the fixed resistance and that one of the first and second electrically conductive support members, the sensing means having an input coupled to the junction and an output, and a control unit having an input coupled to the output of the sensing means and an output coupled to the storage container indicator for activating the storage container indicator when the voltage value reaches a threshold value. 
     The storage container indicator preferably comprises a light source, most preferably an LED, mounted to one of the wall members in a location visible from the exterior of said container. 
     In the preferred embodiment, the sensing means comprises an operational amplifier and the control unit comprises a microcontroller. 
     For a fuller understanding of the nature and advantages of the invention, reference should be made to the ensuing detailed description taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a preferred embodiment of a storage container incorporating the invention; 
         FIG. 2  is a schematic perspective view illustrating the stacked configuration of a plurality of storage containers of the type shown in  FIG. 1  and a local controller, with the storage containers electrically interconnected by means of cables; and 
         FIG. 3  is a schematic view of an indicator circuit according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning now to the drawings,  FIGS. 1 and 2  as described above illustrate a storage container system in which a plurality of essentially identical storage containers  10 -I for file folders capable of being electronically addressed by an associated local controller are arranged in a stacked configuration and electrically interconnected by means of data and power cables. Each storage container  10 -I is provided with a storage container indicator  25 -I, which in the preferred embodiment is an LED with a current draw when activated of about 15.0 mA. 
     Located within each storage container  10 -I is a storage container indicator activation circuit illustrated in  FIG. 3 . As seen in this Fig., a circuit board  50  has mounted thereon a resistor  51 , an amplifier  52 , a microcontroller unit (MCU)  53 , and an isolator circuit  58 . In the preferred embodiment, resistor  51  is a 0.5 ohm one watt resistor; amplifier  52  is a type MCP6002 operational amplifier; and MCU  53  is a type PIC 16F1823 microcontroller unit available from Microchip Technology, Inc. of Chandler, Ariz. Isolator circuit  58  is used to isolate incoming signals on positive data conductor  55  from outgoing response signals generated by MCU  53 , such as the identification of the storage container in which MCU  53  is located (the ID send signal). 
     One terminal of resistor  51  is connected to the positive data conductor  55  of a USB bus. The other terminal of resistor  51  is coupled to the active signal input of amplifier  52  and to electrically conductive rail  17 . The output of amplifier  52  is coupled to a data input of MCU  53 . A control output of MCU  53  is coupled to the anode of indicator  25  of the associated storage container. The cathode terminal of indicator  25  is connected to the negative data conductor  56  of the USB bus. 
     In operation, an incoming address on positive data conductor  55  is coupled via resistor  51  and rail  17  to the electronic circuitry in brace  21  of all folders operationally installed in all storage containers interconnected in the manner described above with reference to  FIG. 2 . When the incoming address matches the address stored in the electronic circuitry in one of the braces  21 , such as the brace  21  illustrated in  FIG. 3 , the visible ADDRESS MATCH indicator  24  on that brace  21  is activated. Activation of the visible ADDRESS MATCH indicator  24  causes substantial current to flow through resistor  51  of the storage container containing the addressed brace  21 . This causes the output of amplifier  52  to change state, which signals MCU  53  to generate a signal to activate the storage container visible indicator  25 . Since the incoming address is unique, no other folder brace visible indicator  24  will be activated. Consequently, only the storage container visible indicator  25  in the storage container in which the addressed folder is located will be activated. As a result, a human operator can merely look for the storage container having the activated visible indicator  25  and proceed to that storage container to retrieve the sought file folder  20 . 
     As noted above, each file folder  20  is provided with a visible POWER ON indicator  23  which is activated whenever the associated file folder  20  is operationally installed in the storage container. In establishing the initial parameters for the storage container indicator activation circuit, the total current draw of the visible POWER ON indicators  23  for the maximum number of file folders  20  which can be accommodated by a given storage container is calculated and the resultant value is used to set the operating threshold of amplifier  52 . This ensures that amplifier  52  will only signal MCU  53  to generate the activation signal for visible indicator  25  when an address match has occurred within a file folder  20  in that storage container. 
     As will now be apparent, storage containers incorporating the invention afford the advantage of providing a unique observable response to the presentation of a file folder address to a file folder having electronic circuitry containing that file folder address. In particular, one and only one of the storage container visible indicators  25  will be activated in response to an address match between an address presented on the data conductor  55  of the data bus and a folder address stored in the folder brace circuitry. Since only one storage container visible indicator  25  will be activated, locating the storage container housing the sought folder identified by the presented address on the bus is reduced to a simple matter of looking for the storage container with the activated visible indicator  25 . 
     Although the above provides a full and complete disclosure of the preferred embodiments of the invention, various modifications, alternate constructions and equivalents will occur to those skilled in the art. For example, while the invention has been described and illustrated with reference to a visible indicator  25 , it is equally applicable to storage container arrays having audible indicators, or a combination of both visible and audible indicators. In addition, while the invention has been described and illustrated in the context of an array of vertically stacked storage containers, it is equally applicable to an array of storage containers which are arranged horizontally or both horizontally and vertically. Moreover, the invention is also conformable to other types of storage container bus interconnection arrangements than the cable arrangement shown and described. One such alternate interconnection arrangement is shown and described in commonly-assigned, co-pending U.S. patent application Ser. No. 13/987,352 filed Jul. 16, 2013 for “Two Stage Draw Latch For Stackable Storage Box With Removable Cover”, now U.S. Pat. No. 9,187,210 issued Nov. 17, 2015, the disclosure of which is hereby incorporated by reference. Therefore, the above should not be construed as limiting the invention, which is defined by the appended claims.