Abstract:
An image forming apparatus capable of receiving a raster image from an image processing controller includes: a transmitting unit transmitting device information of the image forming apparatus to an external device via the image processing controller; a determining unit determining whether the image processing controller is in a first power condition or in a second power condition consuming lower power than the first power condition; and a control unit allowing the transmitting unit to transmit the device information to the external device in a case where the determining unit determines that the image processing controller is in the first power condition, and in a case where the determining unit determines that the image processing controller is in the second power condition, restrict the transmitting unit to transmit the device information to the external device until the image processing controller returns to the first power condition from the second power condition.

Description:
BACKGROUND 
       [0001]    1. Field 
         [0002]    The present invention relates to control of an image forming system which processes images by collaborative operation of an image processing device and an image processing controller. 
         [0003]    2. Description of Related Art 
         [0004]    Recently, the demand for realizing power saving of devices, including an image forming apparatus, is increasing. For meeting this demand, there has been proposed a technology which shifts the power condition of an image forming apparatus to a power saving condition when the image forming apparatus is not operated for a certain period or in other situations (see Japanese Patent Application Laid-Open No. 2010-2500). According to this image forming apparatus, the power condition of the image forming apparatus shifts to the power saving condition after an elapse of a certain period from the end of a printing process performed by a printer unit and a scanner process performed by a scanner unit, or after an elapse of a certain period from the end of communication with an external device. 
         [0005]    There is a type of this image forming apparatus which connects with an image processing controller capable of performing image processing in cooperation with the image forming apparatus. This image processing controller also shifts to the power saving condition when no printing data is processed for a certain period, or when no other information processing device on a network accesses the image processing controller. 
         [0006]    However, the following problems arise from this conventional system. The image forming apparatus connects with a network with the image processing controller interposed between the image forming apparatus and the network. According to this structure, transmission of information from the image forming apparatus to the outside under the power saving condition of the image processing controller is allowed only after the image processing controller is restored from the power saving condition. In this case, the image processing controller needs to be restored from the power saving condition for every transmission to the outside even when immediate transmission is not required. Therefore, improvement is still needed for this type of image forming apparatus in view of power saving and durability of devices. 
       SUMMARY 
       [0007]    It is an object of the invention to provide a mechanism capable of achieving energy saving by reducing the number of times of restoration of an image processing controller from a power saving condition, which controller functions as a data relay from an image forming apparatus. 
         [0008]    An image forming apparatus, capable of receiving a raster image from an image processing controller which generates the raster image, includes: a transmitting unit configured to transmit device information of the image forming apparatus to an external device via the image processing controller; a determining unit configured to determine whether the image processing controller is in a first power condition or in a second power condition which consumes lower power than the first power condition; and a control unit configured to allow the transmitting unit to transmit the device information to the external device in a case where the determining unit determines that the image processing controller is in the first power condition, and configured to restrict the transmitting unit to transmit the device information to the external device until the image processing controller returns to the first power condition from the second power condition in a case where the determining unit determines that the image processing controller is in the second power condition. 
         [0009]    Further features will become apparent from the following description of exemplary embodiments (with reference to the attached drawings). 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  illustrates an example of the general structure of an image forming system according to an embodiment. 
           [0011]      FIG. 2  illustrates an example of the hardware structures of an image forming apparatus and an image processing controller. 
           [0012]      FIG. 3  illustrates an example of a power source circuit of the image forming apparatus. 
           [0013]      FIG. 4  illustrates an example of the hardware structure of a network I/F. 
           [0014]      FIG. 5  illustrates an example of the software structure of the image processing controller. 
           [0015]      FIG. 6  illustrates an example of transition of the power condition of the image processing controller and the image forming apparatus. 
           [0016]      FIG. 7  is a flowchart illustrating an example of a device status information transmitting operation performed by the image forming apparatus. 
           [0017]      FIG. 8  is a flowchart illustrating an example of an e-mail receiving operation performed by the image forming apparatus. 
           [0018]      FIG. 9  is a flowchart illustrating an example of an external transmission job operation performed by the image forming apparatus. 
           [0019]      FIG. 10  illustrates an example of a maximum transmission job holding period setting window of the image forming apparatus. 
           [0020]      FIG. 11  illustrates an example of a SEND job transmission confirmation window of the image forming apparatus. 
           [0021]      FIG. 12  is a flowchart illustrating an example of operation performed by the image processing controller in a power saving condition. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    Exemplary embodiments are hereinafter described in detail with reference to the drawings. 
       &lt;General Structure of Image Forming System&gt; 
       [0023]      FIG. 1  illustrates an example of the general structure of an image forming system according to an embodiment of the invention.  FIG. 1  illustrates an image forming system (image processing system)  100 . The image forming system  100  includes an image forming apparatus (first image processing apparatus)  103 , and an image processing controller (second image processing apparatus)  102 . 
         [0024]    The image forming system  100  connects with a client computer  101  in such a condition as to be communicative with the client computer  101 . The client computer  101  and the image processing controller  102  connect with each other via a LAN  113  in such a condition as to be communicative with each other. The image processing controller  102  and the image forming apparatus  103  connect with each other via a control cable  111  and an image video cable  112 . 
         [0025]    According to this embodiment, the image forming apparatus  103  does not directly connect with the LAN  113 . In other words, the image forming apparatus  103  and the client computer  101  communicate with each other with the image processing controller  102  interposed between the image forming apparatus  103  and the client computer  101 . However, the image forming apparatus  103  may connect with the LAN  113 . In other words, the image forming apparatus  103  may directly connect with the client computer  101  in such a condition as to be communicative with the client computer  101 . 
         [0026]    The client computer  101  starts an application and issues printing instructions and others to the image forming apparatus  103 . The image processing controller  102  performs image processing in cooperation with the image forming apparatus  103 . The image forming apparatus  103  is an MFP (Multiple Function Peripheral). The image forming apparatus  103  includes a scanner unit  104 , an operation unit  105 , an MFP controller  106 , a printer unit (printer engine)  107 , a facsimile unit  108 , an IC card reader  109 , and a finisher  110 . A server  114  is a server which collects and manages device condition information about the image forming apparatus  103 . 
       &lt;Structure of Image Forming System&gt; 
       [0027]      FIG. 2  is a block diagram illustrating an example of the hardware structures of the image forming apparatus  103  and the image processing controller  102 . 
         [0028]    The scanner unit  104  of the image forming apparatus  103  reads a manuscript and inputs image data. The operation unit  105  has various types of keys and a panel. The operation unit  105  receives various types of instructions from a user by way of the various keys. The operation unit  105  displays various types of information on the panel. The MFP controller  106  controls the foregoing scanner unit  104 , printer unit  107  and other components. The MFP controller  106  will be detailed later. 
         [0029]    The printer unit  107  performs printing on a sheet based on image data. The facsimile unit  108  connects with a not-illustrated telephone line, and performs input/output processing of facsimile via the telephone line or others. The IC card reader  109  reads information from an IC card indicating identification of a user. The finisher  110  receives the sheet containing an image formed by the printer unit  107 , and performs various processes such as sheet discharging, sorting, stapling, punching, and cutting for the received sheet. 
         [0030]    The image forming apparatus  103  thus constructed performs the following functions. 
       [COPY Function] 
       [0031]    A COPY function records image data of a manuscript read by the scanner unit  104  on an HDD  211  contained in the MFP controller  106 , and allows the printer unit  107  to perform printing of recorded image data on a sheet. 
       [SEND Function] 
       [0032]    A SEND function transmits image data of a manuscript read by the scanner unit  104  to the client computer  101  via a network. 
       [BOX Function] 
       [0033]    A BOX function records image data of a manuscript read by the scanner unit  104  on the HDD  211  contained in the MFP controller  106 . Moreover, the BOX function stores image data transmitted from the client computer  101  in the HDD  211  contained in the MFP controller  106 . 
       [PRINT Function] 
       [0034]    A PRINT function allows the printer unit  107  to interpret PDL (page description language) data transmitted from the client computer  101 , and print the data. 
       &lt;Details of MFP Controller of Image Processing Apparatus&gt; 
       [0035]    The MFP controller  106  of the image forming apparatus  103  is now detailed with reference to  FIG. 2 . 
         [0036]    The MFP controller  106  includes a CPU  208 , a memory  209 , a network I/F  210 , the HDD  211 , an engine I/F  212 , a video I/F  213 , a reader I/F  215 , a facsimile I/F  216 , and a power source control unit  217 . 
         [0037]    The CPU  208  implements programs stored in a memory unit (memory  209  and HDD  211 ) to control the respective parts of the image forming apparatus  103  via a system bus  214  and perform calculations. The memory  209  functions as a work memory of the CPU  208 . The network I/F  210  transmits and receives control commands to and from the image processing controller  102  via the control cable  111 . 
         [0038]    The HDD  211  is a large-capacity memory unit, and stores various types of control programs performed by the CPU  208  and image data. A memory unit other than the HDD, such as SSD (Solid State Drive), may be equipped. 
         [0039]    The engine I/F  212  transmits and receives control commands to and from the printer unit  107 . The video I/F  213  transmits and receives image data to and from the image processing controller  102  via the image video cable  112 . The reader I/F  215  transmits and receives control commands to and from the scanner unit  104  and the operation unit  105 . The facsimile I/F  216  connects with the facsimile unit  108 . The power source control unit  217  controls power supply to the respective parts of the image forming apparatus  103 . 
       &lt;Details of Image Processing Controller&gt; 
       [0040]    As illustrated in  FIG. 2 , the image processing controller  102  includes a CPU  201 , a memory  202 , an HDD  203 , network I/Fs  204  and  205 , and a video I/F  206 . 
         [0041]    The CPU  201  implements programs stored in the memory unit (memory  202  and HDD  203 ) to control the respective parts of the image processing controller  102  via a system bus  207  and perform calculations. The memory  202  functions as a work memory of the CPU  201 . 
         [0042]    The HDD  203  is a large-capacity memory unit, and stores various types of control programs implemented by the CPU  201 , and image data. A memory unit other than the HDD, such as SSD (Solid State Drive), may be equipped. 
         [0043]    The network I/F  204  communicates with other devices including the client computer  101  via the LAN  113 . The network I/F  205  transmits and receives control commands to and from the image forming apparatus  103  via the control cable  111 . The video I/F  206  transmits and receives image data to and from the image forming apparatus  103  via the image video cable  112 . 
       &lt;Power Source Circuit Diagram of Image Forming Apparatus&gt; 
       [0044]    The power source structure of the image forming apparatus  103  is now described with reference to  FIG. 3 . 
         [0045]      FIG. 3  illustrates an example of a power source circuit of the image forming apparatus  103 . 
         [0046]    The image forming apparatus  103  includes a small-capacity first power source unit  251 , and a large-capacity second power source unit  252 . The first power source unit  251  converts alternate current power source supplied from an AC power source  256  into direct current power source (3.3 V, for example). This direct current power source is supplied to the facsimile unit  108 , the power source control unit  217 , the memory  209 , the network I/F  210 , and others. 
         [0047]    The second power source unit  252  converts the alternate current power source supplied from the AC power source  256  into direct current power source (12 V or 24 V, for example). This direct current power source is supplied to the printer unit  107 , the scanner unit  104 , the finisher  110 , the CPU  208 , the HDD  211 , and others. 
         [0048]    A rocker switch  253  and a relay  254  are provided between the AC power source  256  and the first power source unit  251 . A relay  255  is provided between the AC power source  256  and the second power source unit  252 . The rocker switch  253  is turned on or turned off in accordance with operation of a user. The condition of the rocker switch  253  (OFF condition or ON condition) is notified to the power source control unit  217  described below. 
         [0049]    The power source control unit  217  detects the condition of the rocker switch  253  (ON condition or OFF condition). In addition, the power source control unit  217  switches on-off of the relay  254  and the relay  255 . 
         [0050]    The power source control unit  217  turns on both the relay  254  and the relay  255 . As a result, power is supplied from the first power source unit  251  and the second power source unit  252  to the respective units such as the printer unit  107 , the scanner unit  104 , and the finisher  110 . Accordingly, the image forming apparatus  103  comes into a standby condition. 
         [0051]    On the other hand, the power source control unit  217  turns on the relay  254  and turns off the relay  255 . As a result, power supply from the second power source unit  252  to the printer unit  107 , the scanner unit  104  and others stops. Accordingly, the image forming apparatus  103  comes into a power saving condition  604 . In the power saving condition  604 , power is supplied only to the limited parts such as the power source control unit  217 , the memory  209 , and the network I/F  210 , and is not supplied to the other parts. 
       &lt;Block Diagram of Network I/F&gt; 
       [0052]      FIG. 4  is a block diagram illustrating an example of the hardware structure of the network I/Fs  204 ,  205 , and  210 . The network I/Fs  204 ,  205 , and  210  are network interface devices detachably attached to the image processing controller  102  and the image forming apparatus  103 . 
         [0053]    As illustrated in  FIG. 4 , each of the network I/Fs  204 ,  205 , and  210  includes a CPU  401 , a RAM  402 , a ROM  403 , a network I/F  404 , an LED  405 , an extended I/F  406 , and a system bus  407  connecting these components. The CPU  401  performs various types of controls under a control program stored in the ROM  403 . 
         [0054]    In case of the network I/F  204 , the CPU  401  connects with the LAN  113  via the network I/F  404 , and further communicates with the client computer  101  located on the LAN  113  by way of the LAN  113  in accordance with a predetermined communication protocol, for example. This structure allows the CPU  401  to receive various types of data including printing data and printing control commands transmitted from the client computer  101  and transfer the data to the image processing controller  102  via the extended I/F  406 , and thereby allows the image processing controller  102  to perform image processing, for example. 
         [0055]    The RAM  402  functions as a temporary memory area such as a main memory and a work area of the CPU  401 . The LED  405  functions as an indication unit indicating the operation condition of the network I/F  204 ,  205 , or  210 . The LED  405  indicates the electric connection condition between the network I/F  404  and the LAN  113 , and various operation conditions such as communication modes using colors and blinking patterns of an LED. 
         [0056]    The extended I/F  406  is an I/F for connection between the network I/F  204 ,  205 , or  210  and the image processing controller  102  or the image forming apparatus  103 . The extended I/F  406  connects with a PCI (Peripheral Component Interconnect) bus or the like. 
       &lt;Software Structure of Image Processing Controller&gt; 
       [0057]    The software structure of the image processing controller  102  is now described with reference to  FIG. 5 . 
         [0058]      FIG. 5  is a block diagram illustrating an example of the software structure of the image processing controller  102 . The respective functions of the software illustrated in  FIG. 5  are performed under programs stored in the memory  202  or the HDD  203  of the image processing controller  102  and read and implemented by the CPU  201 . 
         [0059]    An OS  321  is an OS (operating system) corresponding to an operating system of the image processing controller  102 . A print server application  301  is application software operated on the OS  321  and implemented by the CPU  201 . The print server application  301  includes a composition editing unit  311 , a Job control unit  312 , and an RIP processing unit  313 , and performs various processing including image processing. 
         [0060]    The composition editing unit  311  is an editing unit which performs a composition editing process for editing image data on each page into a bookbinding composition format in accordance with instructions from the client computer  101 . The Job control unit  312  is a control unit which controls printing Job in accordance with instructions from the client computer  101 . More specifically, the Job control unit  312  receives printing data from the client computer  101 , issues instructions associated with the printing data, and controls the printing order of the printing Job. The RIP processing unit  313  is a processing unit which converts PDL (Page Description Language) into a printable raster image at the time of composition by the composition editing unit  311  or at the time of actual practice of image forming processing by the Job control unit  312 . 
       &lt;Power Condition Transition of Image Processing Controller and Image Forming Apparatus&gt; 
       [0061]      FIG. 6  illustrates a transition of the power conditions of the image processing controller  102  and the image forming apparatus  103 . 
         [0062]    The power condition of each of the image processing controller  102  and the image forming apparatus  103  according to this embodiment lies in any one of a power source OFF condition  601 , a standby condition (first power condition)  602 , a job practice condition  603 , and the power saving condition (second power condition)  604 . While the four conditions are assumed in this embodiment, the power conditions according to the invention are not limited to these conditions. Each of the image processing controller  102  and the image forming apparatus  103  may lie in other power conditions. 
         [0063]    For example, the image processing controller  102  may be in a suspension condition or a hibernation condition. The suspension condition is a condition where the image processing controller  102  can be restored to the standby condition  602  at a high speed. In the suspension condition, the memory  202  is kept turned on, wherefore the image processing controller  102  starts and shifts to the standby condition  602  from the condition stored in the memory  202  as the condition of the image processing controller  102 . 
         [0064]    Similarly, the hibernation condition is a condition where the image processing controller  102  can be restored to the standby condition at a high speed. In the hibernation condition, the power condition is similar to the power source OFF condition  601 , and power supply to the respective parts of the image processing controller  102  stops. However, the different point from the power source OFF condition  601  is that the condition of the image processing controller  102  is stored in the HDD  203  before shift to the hibernation condition. Restoration of the image processing controller  102  from the hibernation condition to the standby condition is carried out at a high speed based on the information stored in the HDD  203 . 
         [0065]    The order of the high power consumption of the power condition of each of the image processing controller  102  and the image forming apparatus  103  is: Job practice condition  603 &gt;standby condition  602 &gt;power saving condition  604 &gt;power source OFF condition  601 . 
         [0066]    The respective power conditions of the image forming apparatus  103  are now described. 
         [0067]    The power source OFF condition  601  is a condition where the rocker switch  253  of the image forming apparatus  103  is turned off. In this condition, power supply to all the components of the image forming apparatus  103  stops. When the user turns on the rocker switch  253  in the power source OFF condition  601 , the image forming apparatus  103  shifts to the standby condition  602 . 
         [0068]    The standby condition  602  is a condition where the image forming apparatus  103  is waiting for execution of a job. In this condition, power is supplied to all the components of the image forming apparatus  103 . However, power is not required to be supplied to all the components of the image forming apparatus  103 . In other words, only power supply to the essential components is needed, and power supply to other components (such as operation unit  105 ) may be stopped. When receiving a job from the client computer  101  via the image processing controller  102 , the image forming apparatus  103  in the standby condition  602  shifts to the job practice condition  603 . When a factor for shift to power saving is produced in the standby condition  602 , the image forming apparatus  103  shifts to the power saving condition  604 . 
         [0069]    Examples of the factor for shift to power saving include the following examples (1) through (3). 
         [0070]    (1) The user presses a button (not illustrated) for shift to power saving. 
         [0071]    (2) A predetermined period of time elapses without execution of a printing job, a scan job or others in the standby condition  602 . 
         [0072]    (3) A predetermined period of time elapses without access to a remote UI of the image forming apparatus  103  from the client computer  101 . 
         [0073]    When the user turns off the rocker switch  253  in the standby condition  602 , the image forming apparatus  103  is shut down and shifts to the power source OFF condition  601 . Shut down in this context is a process for ending the OS and the applications so as to end the image forming apparatus  103 . 
         [0074]    The job practice condition  603  is a condition where the image forming apparatus  103  is practicing a job. In this condition, power is supplied to all the components of the image forming apparatus  103 . However, power is not required to be supplied to all the components of the image forming apparatus  103  in the job practice condition  603 . In other words, only power supply to the essential components is needed, and power supply to other components (such as operation unit  105 ) may be stopped. In addition, power supply to units not used for practicing the corresponding job may be stopped. More specifically, at the time of practicing a printing job for forming an image on a sheet, power supply to the operation unit  105 , the scanner unit  104 , and others not used for practicing the printing job may be stopped. After the end of the job in the job practice condition  603 , the image forming apparatus  103  shifts to the standby condition  602 . 
         [0075]    The power saving condition  604  is a condition where the image forming apparatus  103  is waiting in the state of power saving. In this condition, power is supplied to a part (containing the network I/F  210 ) of the components of the MFP controller  106  in the structure of the image forming apparatus  103 . Under the power saving condition  604 , power supply to the scanner unit  104 , the printer unit  107 , the operation unit  105  and others stops. When receiving a factor for restoration from power saving in the power saving condition  604 , the image forming apparatus  103  shifts to the standby condition  602 . In addition, the network I/F  210  can respond to a simple packet transmitted via the network while remaining in the power saving condition  604 . This function is referred to as a proxy response. Examples of the simple packet include ARP request, SNMP condition acquisition, ICMP neighbor discovery, and other packets. ARP represents Address Resolution Protocol. SNMP represents Simple Network Management Protocol. ICMP represents Internet Control Message Protocol. 
         [0076]    Examples of the factor for restoration form power saving include the following examples (1) and (2): 
         [0077]    (1) The user presses a button (not illustrated) for restoration from power saving. 
         [0078]    (2) The image forming apparatus  103  receives a job from the client computer  101 . 
         [0079]    The respective power conditions of the image processing controller  102  are now described. 
         [0080]    The power source OFF condition  601  is a condition where the OS of the image processing controller  102  is shut down. When the user turns on a not-illustrated power source switch in the power source OFF condition  601 , the image processing controller  102  shifts to the standby condition  602 . 
         [0081]    The standby condition  602  is a condition where the image forming apparatus  103  is waiting for execution of a job. In the standby condition  602 , power is supplied to all the components of the image processing controller  102 . When receiving a printing job from the client computer  101  in the standby condition  602 , the image processing controller  102  shifts to the job practice condition  603 . When a factor for shift to power saving is produced in the standby condition  602 , the image processing controller  102  shifts to the power saving condition  604 . 
         [0082]    Examples of the factor for shift to power saving include the following examples (1) through (3): 
         [0083]    (1) The user instructs shift to the power saving condition. 
         [0084]    (2) A predetermined period of time elapses without execution of a printing job, a scan job or others in the standby condition  602 . 
         [0085]    (3) A predetermined period of time elapses without access to a job management tool of the image processing controller  102  from the client computer  101 . 
         [0086]    The job practice condition  603  is a condition where the image processing controller  102  is practicing a job. In this condition, power is supplied to all the components of the image processing controller  102 . After the end of the job in the job practice condition  603 , the image processing controller  102  shifts to the standby condition  602 . 
         [0087]    The power saving condition  604  is a condition where the image processing controller  102  is waiting in the state of power saving. In this condition, power is supplied to the network I/Fs  204  and  205  in the structure of the image processing controller  102 . When receiving a factor for restoration from power saving in the power saving condition  604 , the image processing controller  102  shifts to the standby condition  602 . 
         [0088]    Examples of the factor for restoration from power saving include the following examples (1) and (2). 
         [0089]    (1) The user presses the power source button of the image processing controller  102 . 
         [0090]    (2) The image processing controller  102  receives a magic packet. 
         [0091]    The magic packet in this context refers to a network packet specially coded for turning on a power source of a device by way of a network. 
       &lt;Description of Operation Performed by Image Forming Apparatus When Image Forming Apparatus Transmits Device Status Information to Outside&gt; 
       [0092]    Described hereinafter with reference to a flowchart in  FIG. 7  is the operation of the image forming apparatus  103  performed when the image forming apparatus  103  transmits device status information to the external server  114  in the power saving condition of the image processing controller  102 . 
         [0093]      FIG. 7  is a flowchart illustrating an operation example of the image forming apparatus  103  performed when the image forming apparatus  103  transmits the device status information to the external server  114 . 
         [0094]    The flowchart illustrated in  FIG. 7  is carried out under a program deployed in the memory  209  and implemented by the CPU  208 . In this flowchart, the image processing controller  102  is expressed as DFE (Digital Front End). In addition, the power saving condition  604  is expressed as SLEEP. 
         [0095]    The image forming apparatus  103  regularly transmits the device status information to the external server  114 . Examples of the device status information include counter information, jam information, toner information, and error information. When the image forming apparatus  103  transmits the device status information to the external server  114 , the CPU  208  determines whether the image processing controller  102  is in the power saving condition  604  or not (S 701 ). 
         [0096]    When determining that the image processing controller  102  is not in the power saving condition  604  (No in step S 701 ), the CPU  208  allows the network I/F  210  to transmit the device status information to the external server  114  (S 706 ). 
         [0097]    On the other hand, when determining that the image processing controller  102  is in the power saving condition (Yes in step S 701 ), the CPU  208  saves and over-writes the device status information in a determined area of the HDD  211  (S 702 ). As a result, the latest device status information is stored in this area. 
         [0098]    Then, the CPU  208  determines whether the image processing controller  102  has been restored from the power saving condition or not (S 703 ). When determining that the image processing controller  102  has been restored from the power saving condition (Yes in step S 703 ), the CPU  208  allows the network I/F  210  to transmit the device status information updated in step S 602  to the external server  114  (S 706 ). 
         [0099]    On the other hand, when determining that the image processing controller  102  has not been restored from the power saving condition (No in step S 703 ), the CPU  208  shifts the flow to step S 704 . In step S 704 , the CPU  208  determines whether the elapsed time from the previous transmission of the device status information to the external server  114  exceeds a maximum transmission time interval (stored in HDD  211 , for example). When determining that the elapsed time does not exceed the maximum transmission time interval (NO in step S 704 ), the CPU  208  repeats the determinations in steps S 703  and S 704 . 
         [0100]    On the other hand, when determining that the elapsed time exceeds the maximum transmission time interval (Yes in step S 704 ), the CPU  208  shifts the flow to step S 705 . In step S 705 , the CPU  208  transmits a magic packet to the image processing controller  102  via the network I/F  210  and the control cable  111  to restore the image processing controller  102  from the power saving condition (S 705 ). Then, the CPU  208  allows the network I/F  210  to transmit the device status information updated in step S 702  to the external server  114  (S 706 ). 
         [0101]    Described herein with reference to a flowchart illustrated in  FIG. 12  is the operation of the image processing controller  102  performed when the image forming apparatus  103  transmits the device status information to the external server  114  in the power saving condition of the image processing controller  102 . 
         [0102]      FIG. 12  is a flowchart illustrating an operation example of the image processing controller  102  in the power saving condition. 
         [0103]    Under the power saving condition of the image processing controller  102 , the CPU  401  on the network I/F  205  of the image processing controller  102  monitors whether a magic packet addressed to the CPU  401  has been transmitted or not (S 1201 ). When determining that a magic packet addressed to the CPU  401  has not been received (No in step S 1201 ), the CPU  401  repeats determination in step S 1201 . 
         [0104]    On the other hand, when determining that a magic packet addressed to the CPU  401  has been received (Yes in step S 1201 ), the CPU  401  supplies power to the CPU  201  to restore the image processing controller  102  from the power saving condition (S 1202 ). The magic packet received by the image processing controller  102  in this step corresponds to the magic packet transmitted from the image forming apparatus  103  in step S 705  in  FIG. 7 . 
         [0105]    The CPU  201  restored by power supply obtains the memory data immediately before transition to the power saving condition  604  from the HDD  203 , loads the obtained data into the memory  202 , and restores the image processing controller  102  from the power saving condition  604  to the standby condition  602  (S 1203 ). 
         [0106]    Then, the CPU  201  determines whether the network I/F  205  has received the data or not (S 1204 ). When determining that the network I/F  205  has not received the data (No in step S 1204 ), the CPU  201  repeats the determination in step S 1204 . 
         [0107]    On the other hand, when determining that the network I/F  205  has received the data (Yes in step S 1204 ), the CPU  201  shifts the flow to step S 1205 . The data received in this step corresponds to the device status information transmitted from the image forming apparatus  103  in step S 706  in  FIG. 7 . 
         [0108]    In step S 1205 , the CPU  201  transfers the received data (device status information) to the LAN  113  via the network I/F  204  to transmit the device status information to the external server  114 . 
         [0109]    According to the first embodiment, on the occasion of transmission of the device status information to the external server  114 , the image forming apparatus  103  only updates the device status information and does not transmit the device status information to the external server  114  (regulates (reserves) transmission) when the image processing controller  102  is in the power saving condition. When the image processing controller  102  is restored from the power saving condition, the image forming apparatus  103  transmits the device status information to the external server  114 . This structure offers the advantages of reduction of the number of times of restoration of the image processing controller  102  from the power saving condition, and resultant reduction of power consumption. When a predetermined time elapses with transmission of the device status information kept regulated (reserved), the image processing controller  102  is restored from the power saving condition, and allowed to transmit the device status information subjected to transmission regulation (reservation). 
         [0000]    &lt;Description of Operation of Image Forming Apparatus Performed when Image Forming Apparatus Receives E-Mail&gt; 
         [0110]    Described hereinafter with reference to a flowchart in  FIG. 8  is the operation of the image forming apparatus  103  performed when the image forming apparatus  103  receives an e-mail in the power saving condition of the image processing controller  102 . 
         [0111]      FIG. 8  is a flowchart illustrating the operation of the image forming apparatus  103  performed when the image forming apparatus  103  receives an e-mail. The flowchart illustrated in  FIG. 8  is carried out under a program deployed in the memory  209  and implemented by the CPU  208 . In this flowchart, the image processing controller  102  is expressed as DFE (Digital Front End). 
         [0112]    The image forming apparatus  103  has an e-mail receiving function. The image forming apparatus  103  regularly accesses a not-illustrated external e-mail server (POP server) (i.e., transmits an e-mail reception command), and receives an e-mail. The image forming apparatus  103  automatically performs printing when receiving an e-mail. This e-mail printing function receives setting of an e-mail printing time zone. For example, when the e-mail printing time zone is set from 9 a.m. to 5 p.m., an e-mail received at a time out of the time zone from 9 a.m. to 5 p.m. is only received and not printed at that time. 
         [0113]    When the image forming apparatus  103  receives an e-mail, the CPU  208  determines whether the image processing controller  102  is in the power saving condition  604  or not (S 801 ). When determining that the image processing controller  102  is not in the power saving condition  604  (No in step S 801 ), the CPU  208  accesses the POP server (transmits an e-mail reception command thereto) and receives an e-mail (S 805 ). 
         [0114]    On the other hand, when determining that the image processing controller  102  is in the power saving condition  604  (Yes in step S 801 ), the CPU  208  shifts the flow to step S 802 . 
         [0115]    In step S 802 , the CPU  208  determines whether the image processing controller  102  has been restored from the power saving condition  604 . When determining that the image processing controller  102  has been restored from the power saving condition (Yes in step S 802 ), the CPU  208  accesses the POP server (transmits an e-mail reception command thereto), and receives an e-mail (S 805 ). 
         [0116]    On the other hand, when determining that the image processing controller  102  has not been restored from the power saving condition (No in step S 802 ), the CPU  208  determines whether the current time falls within the e-mail printing time zone (S 803 ). When determining that the current time does not lie in the e-mail printing time zone (No in step S 803 ), the CPU  208  repeats the determinations in steps S 802  and S 803 . 
         [0117]    On the other hand, when determining that the current time falls within the e-mail printing time zone (Yes in step S 803 ), the CPU  208  shifts the flow to step S 804 . In step S 804 , the CPU  208  transmits a magic packet to the image processing controller  102  via the network I/F  210  and the control cable  111  to restore the image processing controller  102  from the power saving condition. Then, the CPU  208  accesses the POP server (transmits an e-mail reception command thereto) and receives an e-mail (S 805 ). 
         [0118]    The operation of the image processing controller  102  performed when the image forming apparatus  103  receives an e-mail in the power saving condition of the image processing controller  102  is similar to the corresponding operation described in the first embodiment with reference to  FIG. 12 . However, the image processing controller  102  receives an e-mail reception command (S 1204 ) after restoration from the power saving condition (S 1202 , S 1203 ), and transfers the received e-mail reception command to the LAN  113  (S 1205 ). 
         [0119]    According to the second embodiment, on the occasion of reception of an e-mail by the image forming apparatus  103 , the image forming apparatus  103  does not receive the e-mail (regulates (reserves) transmission of e-mail reception command to e-mail server) when the image processing controller  102  is in the power saving condition. When the image processing controller  102  is restored from the power saving condition, or when the current time falls within the e-mail printing time zone, the image forming apparatus  103  receives the e-mail. This structure offers the advantages of reduction of the number of times of restoration of the image processing controller  102  from the power saving condition for reception of an e-mail in the period out of the e-mail printing time zone, and resultant reduction of power consumption. 
         [0120]    According to this embodiment, the image processing controller  102  is allowed to be restored from the power saving condition and receive an e-mail when the current time falls within the printing time zone. However, in addition to this structure, the image processing controller  102  may be also allowed to be restored from the power saving condition and receive an e-mail when the counted number of times of continuous failure of access to the POP server exceeds a predetermined number (such as ten times). The predetermined number of times of continuous failure of access to the POP server in this context corresponds to a predetermined number of times of continuous regulation (reservation) of e-mail reception command transmission by the CPU  208 . 
         [0121]    Similarly to the first embodiment, the image processing controller  102  in the second embodiment may be configured to be restored from the power saving condition and transmit an e-mail reception command after an elapse of the maximum transmission time interval from the time of the previous transmission of the e-mail reception command. 
         [0122]    Similarly to the second embodiment, the image processing controller  102  in the first embodiment may be configured to be restored from the power saving condition and transmit the device status information when the current time falls within a predetermined time zone set beforehand. 
       &lt;Description of Operation of Image Forming Apparatus Performed When Image Forming Apparatus Transmits Scan Data&gt; 
       [0123]    Described hereinafter with reference to a flowchart in  FIG. 9  is the operation of the image forming apparatus  103  performed when the image forming apparatus  103  transmits scan data in the power saving condition of the image processing controller  102 . 
         [0124]      FIG. 9  is a flowchart illustrating an operation example of the image forming apparatus  103  performed when the image forming apparatus  103  transmits scan data. The flowchart illustrated in  FIG. 9  is executed under a program deployed in the memory  209  and implemented by the CPU  208 . In this flowchart, the image processing controller  102  is expressed as DFE (Digital Front End). 
         [0125]    The image forming apparatus  103  has the SEND function which transmits scan data to the external client PC  101  and server  114 . Examples of the designation method of the transmission destination include designation using a mail address contained in an address book where the user registers transmission destinations beforehand, designation by direct input of a mail address, designation by a registered file server, designation by a file server connected with a network and searched thereon. 
         [0126]    According to the image forming apparatus  103 , the setting of the SEND operation performed in the power saving condition of the image processing controller  102  can be determined beforehand. 
         [0127]      FIG. 10  illustrates an example of a maximum transmission job holding period setting window for determining the setting of the SEND operation performed in the power saving condition of the image processing controller  102 . 
         [0128]    A setting window  1001  is displayed on the operation unit  105  to allow an administrator of the image forming system  100  to determine the setting of the SEND operation using the setting window  1001 . 
         [0129]    A button  1002  is a button for selecting an option that the maximum transmission job holding period is set. The maximum transmission job holding period in this context refers to the maximum holding period from the scan time of scan data to the transmission time of the data. When the button  1002  is selected, a desired maximum transmission job holding period is allowed to be inputted to a blank  1005 . According to the example illustrated in  FIG. 10 , the maximum transmission holding period is set to 3 hours. 
         [0130]    A button  1003  is a button for selecting an option that the maximum transmission job holding period is not set. The button  1003  is selected when immediate transmission of scan data is desired for every transmission. When an OK button  1004  is pressed, the CPU  208  stores the result of the setting in the HDD  211  of the MFP controller  106 , for example. 
         [0131]    At the start of the SEND function by the image forming apparatus  103  under the power saving condition of the image processing controller  102 , the CPU  208  changes the display of the operation unit  105  to a scan data transmission destination setting window (not illustrated) and receives the designation of the transmission destination from the user (S 901 ). 
         [0132]    When the designation of the transmission destination is inputted from the user, the CPU  208  determines the transmission destination inputted by the user (S 902 , S 903 , S 904 ). 
         [0133]    When determining that the transmission destination inputted by the user corresponds to the client PC  101  or the server  114  located on the network and referred to and searched for by the operation unit  105  (No in step S 902 , No in step S 903 , and Yes in step S 904 ), the CPU  208  shifts the flow to step S 905 . 
         [0134]    In step S 905 , the CPU  208  transmits a magic packet to the image processing controller  102  via the network I/F  210  and the control cable  111  to restore the image processing controller  102  from the power saving condition. Then, the CPU  208  actuates the scanner unit  104  and generates scan image data (S 906 ). The CPU  208  transmits the scan image data to the designated transmission destination (S 907 ). 
         [0135]    When determining that the transmission destination inputted by the user corresponds to a mail address set in an address book or others beforehand, or a registered file server (Yes in step S 902 ), the CPU  208  shifts the flow to step S 908 . When determining that the transmission destination inputted by the user corresponds to a mail address or a file server directly inputted (Yes in step S 903 ), the CPU  208  shifts the flow to step S 908 . 
         [0136]    In step S 908 , the CPU  208  actuates he scanner unit  104  and generates scan image data. The CPU  208  further stores the scan image data generated in step S 908  in a transmission job holding area of the HDD  211  (S 909 ). 
         [0137]    Then, the CPU  208  determines whether the image processing controller  102  has been restored from the power saving condition (S 910 ). When determining that the image processing controller  102  has been restored from the power saving condition (Yes in step S 910 ), the CPU  208  transmits the scan image data to the designated transmission destination (S 907 ). 
         [0138]    On the other hand, when determining that the image processing controller  102  has not been restored from the power saving condition (No in step S 910 ), the CPU  208  shifts the flow to step S 911 . In step S 911 , the CPU  208  determines whether the elapsed time from execution of scan in step S 908  exceeds the maximum transmission job holding period set beforehand. When determining that the elapsed time from execution of scan does not exceed the maximum transmission job holding time (No in step S 911 ), the CPU  208  repeats the determinations in steps S 910  and S 911 . 
         [0139]    On the other hand, when determining that the elapsed time from execution of scan exceeds the maximum transmission job holding time (Yes in step S 911 ), the CPU shifts the flow to step S 912 . In step S 912 , the CPU  208  transmits a magic packet to the image processing controller  102  via the network I/F  210  and the control cable  111  to restore the image processing controller  102  from the power saving condition. Then, the CPU  208  transmits the scan image data to the designated transmission destination (S 907 ). 
         [0140]    In the job storing process in step S 909 , a transmission confirmation window  1101  may be displayed on the operation unit  105  as illustrated in  FIG. 11 . 
         [0141]      FIG. 11  illustrates an example of the transmission confirmation window  1101  for determining the setting of the SEND operation performed in the power saving condition of the image processing controller  102 . 
         [0142]    After storing the scan data in the HDD  211 , the CPU  208  allows the SEND job transmission confirmation window  1101  to be displayed on the operation unit  105 . This display of the transmission confirmation window  1101  contains within the message a time  1103  after an elapse of the maximum transmission job holding period (set by the button  1002  in  FIG. 10 ) from the time of scan. In other words, the time displayed as the time  1103  corresponds to the time when the scan data held without transmission is to be transmitted at the latest. 
         [0143]    Accordingly, the message containing the time  1103  notifies the user about the time when the scan data is to be transmitted at the latest. Moreover, this time is printed as the scheduled transmission time under the control of the CPU  208  on the occasion of status printing performed when obtaining information about the job from the operation unit  105  of the image forming apparatus  103 . 
         [0144]    When immediate transmission of scan data is desired, the user presses a “transmit immediately” button  1102 . When the “transmit immediately” button  1102  is pressed, the CPU  208  transmits a magic packet to the image processing controller  102  via the network I/F  210  and the control cable  111  to restore the image processing controller  102  from the power saving condition. Then, the CPU  208  transmits the scan image data to the designated transmission destination. On the other hand, when an OK button  1104  is pressed, the CPU  208  holds the scan image data without transmission, and allows the data to be transmitted only at the time corresponding to the time  1103 . 
         [0145]    When storage of the scan job in the scan job storage area of the HDD  211  is not allowed due to an insufficient capacity or for other reasons at the time of storage of the scan job in step S 909 , the scan data may be transmitted immediately. In this case, the CPU  208  immediately transmits a magic packet to the image processing controller  102  via the network I/F  210  and the control cable  111  to restore the image processing controller  102  from the power saving condition. Then, the CPU  208  transmits the scan image data to the designated transmission destination. 
         [0146]    The operation of the image processing controller  102  performed when the image forming apparatus  103  transmits scan data in the power saving condition of the image processing controller  102  is similar to the corresponding operation in the first embodiment. However, the image processing controller  102  receives scan data (S 1204 ) after restoration from the power saving condition (S 1202 , S 1203 ), and transfers the received scan data to the LAN  113  (S 1205 ). 
         [0147]    According to the third embodiment, on the occasion of transmission of scan data from the image forming apparatus  103 , the image forming apparatus  103  does not transmit the scan data immediately but holds the scan data (regulates (reserves) transmission) in the HDD  211  of the image forming apparatus  103  when the image processing controller  102  is in the power saving condition. After the image processing controller  102  is restored from the power saving condition, or after the period set beforehand elapses from the time of scan, the CPU  208  transmits the scan data. This structure offers advantages of reduction of the number of times of restoration of the image processing controller  102  from the power saving condition for scan data transmission, and resultant reduction of power consumption. 
         [0148]    Similarly to the second embodiment, the image processing controller  102  in the third embodiment may be configured to be restored from the power saving condition and transmit scan data when the current time falls within a predetermined time zone. 
         [0149]    As described above, the image processing controller  102  can be maintained in the power saving condition for the longest possible time when immediate data transmission is not needed from the image forming apparatus  103  to the outside. This advantage contributes to energy saving by reduction of the number of times of restoration of the image processing controller  102  from the power saving condition, which controller  102  functions as a relay for data transmission from the image forming apparatus  103 . 
         [0150]    The respective data structures and contents discussed herein have been presented by way of example only. Obviously, these structures and contents may be constituted by other various types of structures and contents in accordance with the purpose of use and the object. 
         [0151]    While particular embodiments have been described herein, the present invention may be practiced in various forms including a system, a device, a method, a program, a memory medium and so forth. More specifically, the invention is applicable to a system constituted by a plurality of devices, or may be an apparatus constituted by a single device. 
         [0152]    In addition, structures constituted by combinations of the respective embodiments are all included in the scope of the invention. 
         [0153]    The invention may be practiced by the following processes. Software (program) under which the functions of the respective embodiments described herein are performed is supplied to a system or an apparatus via a network or using various types of memory media. The program is read and implemented by a computer (or a CPU, an MPU or the like) of the system or the apparatus. 
         [0154]    The invention is applicable to a system constituted by a plurality of devices, or an apparatus constituted by a single device. 
         [0155]    The invention is not limited to the embodiments described herein. Various modifications (including organic combinations of the embodiments) may be made to the respective embodiments, and these modifications and changes should not be excluded from the scope of the invention. In other words, structures constituted by combinations of the respective embodiments and modified examples thereof are all included in the scope of the invention. 
         [0156]    According to the present invention, energy saving is achieved by reduction of the number of times of restoration of an image processing controller from a power saving condition, which controller functions as a relay for data transmission from an image forming apparatus. 
         [0157]    Embodiments of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions recorded on a storage medium (e.g., non-transitory computer-readable storage medium) to perform the functions of one or more of the above-described embodiment(s) of the present invention, and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more of a central processing unit (CPU), micro processing unit (MPU), or other circuitry, and may include a network of separate computers or separate computer processors. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like. 
         [0158]    While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. 
         [0159]    This application claims the benefit of Japanese Patent Application No. 2013-184255, filed Sep. 5, 2013, which is hereby incorporated by reference herein in its entirety.