Patent Publication Number: US-2007115493-A1

Title: Image forming apparatus, client device, client device control method, and storage medium storing driver program in client device

Description:
PRIORITY INFORMATION  
      This application claims priority to Japanese Patent Application No. 2005-333938 filed on Nov. 18, 2005, which is incorporated herein by reference in its entirety.  
     BACKGROUND  
      1. Technical Field  
      The present invention relates to an image forming system in which a print restriction specified for each user in an image forming apparatus is reflected in the settings of a client device.  
      2. Related Art  
      Conventionally, a printer, a multifunction machine, or the like shared by multiple users has been used in conjunction with a-printing management server or the like to realize functions of measuring and managing monochrome (black and white) and color printed records, usage track records organized by user or by division, and others. Such a printer or a multifunction machine often further includes a restriction function for specifying an output limit for each user employing the above-described functions of measuring and managing, to prohibit the printer or the multifunction machine from outputting documents beyond that output limit.  
     SUMMARY  
      A method for controlling an image forming system wherein a print restriction is stored in a client device and an image forming apparatus, and print data is created by the client device using the print restriction stored in the client device and printed from the image forming apparatus, is provided. The method includes an inquiry step of issuing an inquiry from the client device to the image forming apparatus according to a print instruction from a user to determine whether or not the print restriction stored in the client device differs from the print restriction stored in the image forming apparatus, and a print data output step in which the print restriction stored in the client device is updated to the print restriction obtained from the image forming apparatus by the client device when there is a difference between the print restrictions, the print data is created using the updated print restriction, and the created print data is output to the image forming apparatus. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      An embodiment of the present invention will be described in detail based on the following figures, wherein:  
       FIG. 1  schematically shows a configuration of an image forming system according to an embodiment of the present invention;  
       FIG. 2  is a message diagram for explaining a flow of information exchanged between an image forming apparatus and a client device according to the embodiment of the present invention;  
       FIG. 3  is another message diagram for explaining the flow of information exchanged between the image forming apparatus and the client device according to the embodiment of the present invention;  
       FIG. 4  is a still another message diagram for explaining the flow of information exchanged between the image forming apparatus and the client device according to the embodiment of the present invention;  
       FIG. 5  is a diagram showing an example of screen display associated with an update of a print restriction displayed by a printer driver according to the embodiment of the present invention; and  
       FIG. 6  is a diagram showing an example of screen display associated with print settings of the printer driver according to the embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION  
      Referring to the drawings, an embodiment of the present invention will be described below.  
       FIG. 1  is a diagram schematically showing a configuration of an image forming system  1  according to the present embodiment. The image forming system  1  includes a client device  14 , an image forming apparatus  10  which performs color and monochrome printing, and a print restriction database  12  in which print restrictions for each user are managed. The client device  14  is connected via a network  20  to the image forming apparatus  10 . The image forming apparatus  10  may be implemented by a multifunction machine combining the functions of a color/monochrome printer, a copier, a scanner, a facsimile, and the like.  
      The print restriction database  12  stores user specific print restrictions. An operator can change the user specific print restrictions as required. As shown in  FIG. 1 , the print restriction database  12  stores a user A specific print restriction  41 , a user B specific print restriction  42 , and a user C specific print restriction  43 .  
      Each client device  14  stores at least one of the print restrictions associated with each user of the client device  14 . Further, the client device  14  has a printer driver  31  which creates data to be printed by an image forming unit in the image forming apparatus  10 . Each printer driver  31  retrieves the print restrictions, or the user specific print restrictions (user A, B, and C specific print restrictions.  41  to  43 ) stored in the image forming apparatus in response to a print data output request from the user (user A˜user C) to create print data using the retrieved print restrictions, and outputs the created print data to the image forming apparatus  10 .  
      In the example shown in  FIG. 1 , the user A uses both of the client devices  14   a  and  14   b,  while the user B uses only the client device  14   a,  and the user C uses only the client device  14   b.    
      In response to a print request from the client device, the image forming apparatus  10  looks up the print restriction for each user stored in the print restriction database  12 , and determines whether or not the print request satisfies the print restriction. If the print request satisfies the print restriction, the image forming apparatus  10  enables printing and outputs a color or monochrome printout  16 . If the print request does not satisfy the print restriction, on the other hand, the image forming apparatus  10  disables the printing.  
      FIGS.  2  to  4  are message diagrams for explaining a flow of information exchanged between the image forming apparatus and the client device according to this embodiment.  
      In a process shown in  FIG. 2 , an operator previously specifies settings for all users who perform printing using the image forming apparatus  10 . Here, the process will be described with respect to a user A as an example. The operator creates the user A specific print restriction  41  necessary for the user A to output a print using the image forming apparatus  10  (step S 10 ).  FIG. 2  shows an example of the user A specific print restriction  41  which may include, for example, an identifier for identifying the print restriction of the user, an upper limit for the number of pages which can be output in one step, and an upper limit for the monthly total number of output pages, separately organized for color and monochrome printing.  
      Although, in  FIG. 2 , the user A specific print restriction  41  stored in the image forming apparatus  10  is sent to the client device  14   a  and registered in the client device  14   a  (step S 12 ), this step S 12  is provided here as one example and may be eliminated. When step S 12  is not provided, the user A specific print restriction  41  may be obtained, for example, according to an instruction from the user via a printer driver  31   a,  which will be described later, and registered in the client device  14   a.    
      The identifier of the user A specific print restriction  41  may be configured with a combination of a user name and a date and time when the print restriction is created or updated, such as, for example, “usera2005/01/12” as shown in  FIG. 2 . The identifier is not limited to the combination of the user name and the date and time, however, and may be configured with a combination of the user name and a version number of the print restriction, or a value with which a state of update can be judged, such as a hash value of the print restriction.  
      Then, the operator can make modifications to the user A specific print restriction  41  in the image forming apparatus  10 . If the operator modifies the user A specific print restriction  41 , for example, such that color printing is prohibited and the number of pages output in one process for monochrome printing is changed from unlimited pages to 100 pages, and the modified settings are not sent to the client device  14   a  after the modifications have been made, there arises a discrepancy between the modified user A specific print restriction  41  and the user A specific print restriction  41  stored in the client device  14   a  (step S 16 ).  
      In this situation, if the user A issues a request for color printing, the request is generally rejected by the image forming apparatus  10 .  
      As a possible configuration for eliminating the occurrence of such a rejection, the image forming apparatus  10  may force regular transmission of the print restriction retained in the image forming apparatus  10  to the client devices  14   a,    14   b,  and others, regardless of the presence or absence of the modifications. However, such a configuration is not preferable because the forced regular transmission significantly increases the load on the network in cases where the print restriction must be sent to a great number of client devices and where the variety of the print restrictions to be specified is great. Accordingly, processes shown in  FIGS. 3 and 4  may be more preferably performed in the present embodiment.  
      In the process shown in  FIG. 3 , when the user A instructs color printing, for example, in step S 18 , the printer driver  31   a  reads out the user A specific print restriction  41  stored in the client device  14   a  (step S 19 ) and sends the identifier of the read out user A specific print restriction  41  from the client device  14   a  to the image forming apparatus  10  (step S 20 ). If the client device  14   a  stores no print restriction, the printer driver  31   a  transmits information of “no identifier” (not illustrated) to the image forming apparatus  10 .  
      Next, the image forming apparatus  10  compares the transmitted identifier “usera2005/01/12” (or information of “no identifier”) with an identifier “usera2005/02/20” of the user A specific print restriction  41  stored in the print restriction database  12  to determine whether or not the print restriction is updated (step S 22 ). The print restriction may be determined to have been updated when there is a difference between the identifiers. Alternatively, only date and time portions of the identifiers may be compared, and the print restriction may be determined to have been updated when the date and time portion of the identifier stored in the print restriction database  12  denotes a later date and time relative to that denoted by the date and time portion of the transmitted identifier.  
      After determining the update in step S 22 , the image forming apparatus  10  outputs the user A specific print restriction  41  to the client device  14   a  (step S 28 ). The client device  14   a,  on the other hand, receives and stores the user A specific print restriction  41  output from the image forming apparatus  10  (step S 30 ).  
      In the process of  FIG. 4 , the printer driver  31   a  compares the identifier of the user A specific print restriction  41  newly stored in step S 30  with the identifier of the prestored user A specific print restriction  41  (step S 32 ). Upon detection of the update to the print restriction, the printer driver  31  displays a window (refer to  FIG. 5 ) to notify the user of the update of print restriction information (step S 34 ).  
      In the window shown in  FIG. 5 , the printer driver  31   a  provides the user with two messages “restriction information has been updated” and “proceed to download the print restriction from the server?”. To cancel downloading of the print restriction, the user can click a “cancel” button  62  which causes the print driver  31   a  to end processing.  
      When it is necessary to check detailed information in the window shown in  FIG. 5 , the user can click a “display details” button  63 , which invokes another window including detailed information of the printer driver  31   a  as shown in  FIG. 6 . Then, the printer driver  31   a  reflects the restriction information obtained in accordance with determination of the update to the print restriction onto print settings of the printer driver  31   a  and displays the print settings including updated information (step S 32 ).  
      As a result, the printer driver  31   a  displays information of the print restriction that “color printing is unavailable. Up to  100  pages are printed in one step” in a message area  65  shown in  FIG. 6 , and displays a “color mode” pull-down switch  66  set to a monochrome mode in a state where changing of the mode is disabled.  
      When an OK button  64  is selected to close the window of print settings shown in  FIG. 6 , the window of  FIG. 5  reappears. Next, when the user clicks an OK button  61  of  FIG. 5  to update the restriction information, the printer driver  31   a  detects the input as an instruction for updating the restriction information (step S 36  in  FIG. 4 ) and performs update processing (step S 38  in  FIG. 4 ). Consequently, the printer driver  31   a  updates the print restriction stored in the printer driver  31   a  based on the user A specific print restriction  41  stored in the previous step (step S 38  in  FIG. 4 ).  
      Next, in step S 42 , the printer driver  31   a  generates print data described in a page description language (PDL) using the updated user A specific print restriction  41 . The generated print data is output by the printer driver  31   a  to the image forming apparatus  10 . Upon receipt of the print data, the image forming apparatus  10  performs printing after confirming that the print restriction is satisfied (step S 48 ).  
      In the determination as to whether or not the print restriction is updated (step S 22 ) in  FIG. 3 , when “no update” is determined, the operation proceeds to step S 42 . In step S 42 , the printer driver  31   a  generates print data without updating the user A specific print restriction  41 , and outputs the generated print data to the image forming apparatus  10 . Upon receipt of the print data, the image forming apparatus  10  performs printing after confirming that the print restriction is satisfied (step S 48 ).  
      Because the printer driver  31  outputs the identifier including the user name for each print request from the user, it is preferable that processing for protecting data, such as encryption, be employed in communication between the image forming apparatus  10  and the client device  14 .  
      In the above-described embodiment, information regarding restrictions on print functions that are supplied to the user by the image forming apparatus  10  is registered as the print restriction in the image forming apparatus  10  and the client device  14   a.  As an example modification, user specific setting information, such as a user specific header or footer to be inserted in a page image in printing operation, may be added to the print restriction. With this configuration, when user specific setting information is newly specified or altered in the image forming apparatus  10 , the specified or altered setting information is automatically registered in the client device  14   a  used by the corresponding user according to the scheme of the above-described example.  
      Although, in the above example modification, the restrictions on the print functions of the image forming apparatus  10  and the user specific setting information are registered as the print restriction in the image forming apparatus  10  and the client device  14   a,  driver management information, such as a version number used for managing the update to the printer driver  31  in the client device  14   a,  may be added in the image forming system  1 , to separately detect the presence or absence of updates to the print restriction and the printer driver  31   a.    
      More specifically, in response to the print request from the user, the client device  14   a  sends the identifier of the print restriction  41  stored in the client device  14   a  and the management information of the printer driver  31   a  to the image forming apparatus  10 . Upon receipt of the identifier and the management information, the image forming apparatus  10  compares the received identifier and management information with the identifier and management information retained in the image forming apparatus  10  to individually determine, for each of the print restrictions and the printer driver  31   a,  whether or not an update is present. When the image forming apparatus  10  detects an update to the print restriction, the update is automatically registered in the client device  14   a  according to the scheme of the above-described embodiment. On the other hand, when the image forming apparatus  10  detects the update to the printer driver  31 , the update to the printer driver  31   a  is sent to the client device  14   a.  Upon receipt of the update, the client device  14   a  notifies the user of a request for updating the printer driver  31   a  and updates the printer driver  31   a  according to instructions from the user.  
      Although the embodiment of the present invention was described with a certain degree of detail using specific examples, it is to be understood that the invention is not limited thereto. It is further understood by those skilled in the art that various changes and modifications may be made in the invention without departing from the spirit and scope thereof.