Abstract:
An image forming system including a print data management device and an image forming apparatus, the image forming apparatus receiving print data associated with a print job from a print data management device, if the print data is associated with a first operation and the print data management device is in an enabled state, receiving the print data from an information processing apparatus, if the print data is associated with a second operation, receiving the print data from the information processing apparatus, if the print data management device is in a disabled state, printing the print data associated with the print job on a recording medium, generating history information relating to the print job, the history information including identification information identifying whether the print job that has been printed is associated with the first operation or the second operation, and transmitting the history information to the print data management device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to and incorporates by reference the entire contents of Japanese Patent Application No. 2011-009955 filed in Japan on Jan. 20, 2011. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image forming system, a print data management device, and a method of controlling a print data management device. In particular, the present invention relates to a technique for managing history of output operations of formed images. 
     2. Description of the Related Art 
     Recently, digitization of information has been promoted and thus image processing apparatuses are inevitable. For example, a printer or a facsimile for outputting digitized information, and a scanner for digitizing documents are used. The image processing apparatus includes an imaging function, an image forming function, a communication function, and the like; and in many cases, the image processing apparatus is of a multi-function peripheral which can be used as a printer, a facsimile, a scanner, and a copy machine. 
     From among the image processing apparatuses, as a system which uses a printer to output digitized information, a pull print system is known in which a print job generated in an information processing apparatus, such as a personal computer (PC), is stored in a server; and the printer side acquires a print job through access to the server to form and output the image (for example, see Japanese Patent Application Laid-open No. 2008-107921). 
     In the system described in Japanese Patent Application Laid-open No. 2008-107921, since it is assumed that the server manages the print job, when the server is in a disabled state, it is difficult for the PC to transmit the print job, for the server to store the print job, and for the printer to acquire the print job through access to the server. With a spare server provided, it is possible to solve the above problems, but the problem with such a solution is that introduction and management of a server requires an additional cost. Moreover, since the print job is managed by a plurality of servers, log information is distributed, and thus centralized management cannot be performed. 
     When the server is in disabled state, a direct print job may be transmitted from the PC to the printer, so outputting of a printing job is not disabled. However, in this case, log information is not left on the server side during the disabled state of the server, so that centralized management of log information cannot be performed. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to at least partially solve the problems in the conventional technology. 
     According to an embodiment, there is provided an image forming system that includes: an information processing apparatus that generates and transmits print data; a print data management device that accumulates the transmitted print data and manages print data and log information concerning print data; and an image forming apparatus that prints print data, the information processing apparatus, the print data management device, and the image forming apparatus being communicably connected together. The information processing apparatus includes: a print data generating unit that generates print data, and a print data transmission unit that transmits the print data to either the print data management device or the image forming apparatus in accordance with the operation state of the print data management device. The image forming apparatus includes a print data acquiring unit that acquires the print data from the print data management device, a print data storage unit that stores the print data transmitted from the information processing apparatus into a storage medium, a print output unit that outputs the print data, and a history information holding unit that, when the print data output from the print output unit is print data received from the information processing apparatus, generates history information relating to print output added with identification information for identifying output using print data received from the information processing apparatus and stores the history information into the storage medium. The print data management device includes a print data managing unit that manages and stores the print data transmitted from the information processing apparatus into storage medium, a request print data transmission unit that transmits the print data stored in the storage medium to the image forming apparatus in response to a request from the image forming apparatus, a history information generating unit that generates history information for the print data managed by the print data managing unit, a history information acquiring unit that, from the image forming apparatus, acquires at least the history information added with the identification information from among the history information relating to print output stored in the storage medium of the image forming apparatus at a predetermined timing, and a history information managing unit that manages and stores the history information into the storage medium. 
     According to another embodiment, there is provided a print data management device for an image forming system that includes: an information processing apparatus that generates and transmits print data, the print data management device that accumulates the transmitted print data and manages the print data and log information concerning the print data, and an image forming apparatus that prints the print data. The information processing apparatus transmits the print data to either the print data management device or the image forming apparatus in accordance with the operation state of the print data management device. When the print data is print data received from the information processing apparatus, the image forming apparatus generates and outputs history information relating to print output that is added with identification information for identifying an output using print data received from the information processing apparatus and stores the history information into the storage medium. The print data management device includes: a print data managing unit that manages and stores the print data transmitted from the information processing apparatus into the storage medium; a request print data transmission unit that transmits the print data stored in the storage medium to the image forming apparatus in response to a request from the image forming apparatus; a history information generating unit that generates history information for the print data managed by the print data managing unit; a history information acquiring unit that, from the image forming apparatus, acquires at least the history information added with the identification information from among the history information relating to print output stored in the storage medium of the image forming apparatus at a predetermined timing; and a history information managing unit that manages and stores the history information into the storage medium. 
     According to still another embodiment, there is provided a method of controlling a print data management device for an image forming system that includes: an information processing apparatus that generates and transmits print data, the print data management device that accumulates the transmitted print data and manages the print data and log information concerning the print data, and an image forming apparatus that prints the print data. The information processing apparatus transmits the print data to either the print data management device or the image forming apparatus in accordance with the operation state of the print data management device. When the print data is print data received from the information processing apparatus, the image forming apparatus generates and outputs history information relating to print output that is added with identification information for identifying an output using print data received from the information processing apparatus and stores the history information into the storage medium. The method includes: storing and managing the print data transmitted from the information processing apparatus into the storage medium; transmitting the print data stored in the storage medium to the image forming apparatus in response to a request from the image forming apparatus; generating history information for the print data managed by the print data managing unit; from the image forming apparatus, acquiring at least the history information added with the identification information from among the history information relating to print output stored in the storage medium of the image forming apparatus at a predetermined timing; and storing and managing the history information into the storage medium. 
     The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating the operation form of a system according to an embodiment; 
         FIG. 2  is a block diagram schematically illustrating the hardware configuration of a job management server; 
         FIG. 3  is a block diagram illustrating the functional configuration of an image forming apparatus; 
         FIG. 4  is a block diagram illustrating the functional configuration of a job management; 
         FIG. 5  is a block diagram illustrating the functional configuration of a client terminal; 
         FIG. 6  is a sequence diagram illustrating a normal operation of a system; 
         FIG. 7  is a diagram illustrating an example of log information; 
         FIG. 8  is a sequence diagram illustrating an operation of a system; 
         FIGS. 9A to 9D  are diagrams illustrating an example of log information; 
         FIG. 10  is a flowchart illustrating the operation of a client terminal; 
         FIG. 11  is a flowchart illustrating an operation of a job management server; and 
         FIG. 12  is a flowchart illustrating the operation of a job management server. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, an embodiment will be described in detail. In this embodiment, as an example of an image forming system, a pull print system will be described in which a print job generated in an information processing apparatus, that is, print data is primarily stored in a server, the print job is acquired through access to the server from an image forming apparatus side, and image formation output is performed. 
       FIG. 1  is a diagram illustrating an example of the operation form of a system of this embodiment. As illustrated in  FIG. 1 , the system of this embodiment has a configuration in which an image forming apparatus  1   a , an image forming apparatus  1   b , a client terminal  2 , and a job management server  3  are connected together through a network. 
     The image forming apparatuses  1   a  and  1   b  (hereinafter, collectively referred to as an image forming apparatus  1 ) are multi-function peripherals (MFPs) which include an imaging function, an image forming function, a communication function, and the like, and are usable as a printer, a facsimile, a scanner, and a copy machine. In this embodiment, the image forming apparatus  1  accesses the job management server  3  in accordance with an operation of a user, acquires a print job stored in the job management server  3 , and performs image formation output. 
     The client terminal  2  is an information processing terminal which is operated by the user, and is formed as an information processing apparatus, such as a personal computer (PC). When generating and outputting a print job, in principle, the client terminal  2  of this embodiment transmits the print job to the job management server  3 , but when the job management server  3  is in the disabled state, the client terminal  2  transmits the print job to the image forming apparatus  1 . 
     The job management server  3  functions as a print data management device which receives the print job from the client terminal  2 , temporarily stores the print job, and outputs the print job in accordance with access from the image forming apparatus  1 . Accordingly, log information of the print job is accumulated in the job management server  3 . When having returned from the disabled state, the job management server  3  of this embodiment accesses the image forming apparatus  1 , and collects the log of image formation output in the image forming apparatus  1  in the disabled state. This process is one of the subject matters of this embodiment. In  FIG. 1 , the function of the job management server  3  is realized as a server, and may be realized by an MFP, such as the image forming apparatus  1 . 
     Next, the hardware configuration of the image forming apparatus  1 , the client terminal  2 , and the job management server  3  of this embodiment will be described.  FIG. 2  is a block diagram illustrating the hardware configuration of the job management server  3  of this embodiment. The image forming apparatus  1  includes an engine for realizing a scanner, a printer, or the like, in addition to the hardware configuration illustrated in  FIG. 2 . Although in the following description, the hardware configuration of the job management server  3  will be described, the same is applied to the image forming apparatus  1  and the client terminal  2 . 
     As illustrated in  FIG. 2 , the job management server  3  of this embodiment has the same configuration as a general server, a PC, or the like. That is, in the job management server  3  of the embodiment, a central processing unit (CPU)  10 , a random access memory (RAM)  20 , a read only memory (ROM)  30 , a hard disk drive (HDD)  40 , and an I/F  50  are connected together through a bus  80 . A liquid crystal display (LCD)  60  and an operating unit  70  are connected to the I/F  50 . 
     The CPU  10  is an arithmetic unit and controls the overall operation of the job management server  3 . The RAM  20  is a volatile storage medium in which information is readable and writable at high speed, and is used as a work area when the CPU  10  processes information. The ROM  30  is a nonvolatile read-only storage medium, and stores a program, such as firmware. The HDD  40  is a nonvolatile storage medium in which information is readable and writable, and stores an operating system (OS), various control programs, application programs, and the like. 
     The I/F  50  connects and controls the bus  80  and various kinds of hardware, a network, or the like. The LCD  60  is a visual user interface which is used to confirm the state of the job management server  3 . The operating unit  70  is a user interface, such as a keyboard or a mouse, which is used when the user inputs information to the job management server  3 . As described with reference to  FIG. 1 , the job management server  3  of this embodiment is operated as a server. Accordingly, the user interface, such as the LCD  60  and the operating unit  70 , may not be provided. 
     In the hardware configuration, a program stored in a storage medium, such as the ROM  30 , the HDD  40 , or an optical disk (not illustrated), is read to the RAM  20  and operated under the control of the CPU  10 . Thus, a software controller is constituted. A combination of the software controller constituted as above and hardware constitutes functional blocks which realize the functions of the image forming apparatus  1 , the client terminal  2 , and the job management server  3  of this embodiment. 
     Next, the functional configuration of the image forming apparatus  1  of this embodiment will be described with reference to  FIG. 3 .  FIG. 3  is a block diagram illustrating the functional configuration of the image forming apparatus  1  of this embodiment. As illustrated in  FIG. 3 , the image forming apparatus  1  of this embodiment has a controller  100 , an auto document feeder (ADF)  101 , a scanner unit  102 , a discharge tray  103 , a display panel  104 , a paper feeding table  105 , a printer engine  106 , a discharge tray  107 , and a network I/F  108 . 
     The controller  100  includes a main control unit  110 , an engine control unit  120 , an image processing unit  130 , an operation display control unit  140 , an input/output control unit  150 , and a log managing unit  160 . As illustrated in  FIG. 3 , the image forming apparatus  1  of this embodiment is constituted as a multi-function peripheral having the scanner unit  102  and the printer engine  106 . In  FIG. 3 , electrical connection is indicated by a solid-line arrow, and the flow of a sheet or document is indicated by a broken-line arrow. 
     The display panel  104  serves as an output interface which visually displays the state of the image forming apparatus  1 , as well as an input interface which is a touch panel and is used when the user directly operates the image forming apparatus  1  or inputs information to the image forming apparatus  1 . That is, the display panel  104  includes a function of displaying an image which is used to receive an operation of the user. The display panel  104  is realized by the LCD  60  and the operating unit  70  illustrated in  FIG. 2 . In this embodiment, the user operates the display panel  104  to issue an instruction to select and acquire a print job stored in the job management server  3 . 
     The network I/F  108  is an interface which is used when the image forming apparatus  1  performs communication with another apparatus, such as the client terminal  2  or the job management server  3 , through a network. Ethernet (Registered Trademark) or a universal serial bus (USB) interface is used. The network I/F  108  is realized by the I/F  50  illustrated in  FIG. 2 . The network I/F  108  includes a function as a FAX modem, and functions as an interface which is used when the image forming apparatus  1  performs FAX transmission and reception through a network. 
     The controller  100  is formed of a combination of software and hardware. Specifically, a program stored in a nonvolatile storage medium, such as the ROM  30  or a nonvolatile memory and the HDD  40  or an optical disk, is loaded on a volatile memory (hereinafter, referred to as a memory), such as the RAM  20 . The controller  100  is constituted by a software controller which is constituted when the CPU  10  is operated in accordance with the program and hardware, such as an integrated circuit. The controller  100  functions as a control unit which performs overall control of the image forming apparatus  1 . 
     The main control unit  110  functions to control the respective units of the controller  100 , and provides commands to the respective units of the controller  100 . The engine control unit  120  functions as a driving unit which controls or drives the printer engine  106 , the scanner unit  102 , and the like. The image processing unit  130  generates drawing information on the basis of image information to be printed and output under the control of the main control unit  110 . The drawing information is information which is used when the printer engine  106  serving as an image forming unit draws an image to be formed in an image forming operation. 
     The image processing unit  130  processes imaging data input from the scanner unit  102  to generate image data. Image data is information which is stored in the storage area of the image forming apparatus  1  or is transmitted to the job management server  3  through the network I/F  108  as the result of the scanner operation. 
     The operation display control unit  140  displays information on the display panel  104  or gives notification of information input through the display panel  104  to the main control unit  110 . The input/output control unit  150  inputs information input through the network I/F  108  to the main control unit  110 . The main control unit  110  controls the input/output control unit  150  and accesses another apparatus, such as the client terminal  2  or the job management server  3 , through the network I/F  108  and the network. 
     When image formation output is performed in the image forming apparatus  1 , the log managing unit  160  stores the log information. When storing the log information, the log managing unit  160  provides information for identifying image formation output by a print job acquired through the job management server  3  or image formation output by a print job directly input from the client terminal  2 . Log information of image formation output by a print job directly input from the client terminal  2  is transmitted in accordance with access from the job management server  3 . 
     When the image forming apparatus  1  operates as a printer, first, the input/output control unit  150  receives a print job through the network I/F  108 . That is, the input/output control unit  150  functions as a print data acquiring unit. The input/output control unit  150  transfers the received print job to the main control unit  110 . When the print job is received, the main control unit  110  performs control such that the image processing unit  130  generates drawing information on the basis of document information or image information included in the print job. 
     When the drawing information is generated by the image processing unit  130 , the engine control unit  120  performs control such that the printer engine  106  performs image formation on a sheet fed from the paper feeding table  105  on the basis of the generated drawing information. That is, the image processing unit  130 , the engine control unit  120 , and the printer engine  106  function as a print output unit. As a specific form of the printer engine  106 , an ink jet type image forming mechanism, an electrophotographic image forming mechanism, or the like may be used. A document which is subjected to image formation by the printer engine  106  is discharged to the discharge tray  107 . During this process, the log managing unit  160  stores the log information in a storage medium, such as the HDD  40 , under the control of the main control unit  110 . That is, the log managing unit  160  functions as a history information holding unit of the image forming apparatus. 
     Next, the functional configuration of the job management server  3  of this embodiment will be described with reference to  FIG. 4 . As illustrated in  FIG. 4 , the job management server  3  of this embodiment has a controller  300  and a network I/F  310 . The controller  300  includes an input/output control unit  301 , a job managing unit  302 , a log managing unit  303 , and an apparatus managing unit  304 . 
     The network I/F  310  is an interface which is used when the job management server  3  performs communication with another apparatus, such as the image forming apparatus  1  or the client terminal  2 , through a network. Ethernet (Registered Trademark) or a USB interface is used. 
     Similarly to the controller  100  of the image forming apparatus  1 , the controller  300  is formed of a combination of software and hardware, and functions as a control unit which controls the job management server  3 . Similarly to the input/output control unit  150  of the image forming apparatus  1 , the input/output control unit  301  controls transmission and reception of information through the network I/F  310 . 
     The job managing unit  302  primarily stores a print job, which is received by the input/output control unit  301  from the client terminal  2  through the network, into the storage medium, such as the HDD  40 . The print job stored in the storage medium is read and is output in accordance with access from the image forming apparatus  1 . That is, the input/output control unit  301  functions as a command reception unit, and the job managing unit  302  functions as a print data managing unit and a request print data transmission unit. The apparatus managing unit  304  holds information for managing the apparatus, such as the network address of the image forming apparatus  1  as a print job management target, that is, in this embodiment, the network addresses of the image forming apparatus  1   a  and the image forming apparatus  1   b , or the like, and manages the image forming apparatus  1 . 
     The log managing unit  303  stores the history of the print job into the storage medium, such as the HDD  40 , as the print job is stored and output by the job managing unit  302 . This embodiment resides in that the log managing unit  303  performs centralized management of log information of image formation output in the image forming apparatus  1   a  and the image forming apparatus  1   b . For this reason, when the job management server  3  returns from the disabled state, the log managing unit  303  of this embodiment acquires the log information of image formation output from the image forming apparatus  1  through the input/output control unit  301 . That is, the log managing unit  303  functions as a history information generating unit, a history information acquiring unit, and a history information managing unit of an image formation control device. 
     Next, the functional configuration of the client terminal  2  of this embodiment will be described with reference to  FIG. 5 . As illustrated in  FIG. 5 , the client terminal  2  of this embodiment has a controller  200  and a network I/F  210 , in addition to the LCD  60  and the operating unit  70  described in the embodiment The controller  200  includes an application  201 , a printer driver  202 , a user I/F controller  203 , and an input/output control unit  204 . 
     The network I/F  210  is an interface which is used when the client terminal  2  performs communication with another apparatus, such as the image forming apparatus  1  or the job management server  3 , through a network. Ethernet (Registered Trademark) or a USE interface is used. 
     Similarly to the controller  100  of the image forming apparatus  1 , the controller  200  is formed of a combination of software and hardware, and functions as a control unit which controls the client terminal  2 . Similarly to the input/output control unit  150  of the image forming apparatus  1 , the input/output control unit  204  controls transmission and reception of information through the network I/F  310 . 
     The application  201  is a software application which is constituted such that the CPU  10  performs an arithmetic operation (or, calculating operation) in accordance with a software program installed in the client terminal  2 , and which allows the user to perform browsing, editing, managing, and the like on image information or document information. The user performs image formation output for the image information or the document information through the application  201 . 
     When an instruction to perform image formation output is issued through the application  201 , the printer driver  202  generates a print job on the basis of image information or document information to be subjected to image formation output, and transmits the print job to the image forming apparatus  1  or the job management server  3  through the input/output control unit  204 . That is, the printer driver  202  functions as a print data generating unit and a print data transmission unit. The print job generated by the printer driver  202  is information which is described in a page description language (PDL). 
     The user I/F controller  203  displays a graphical user interface (GUI) of the application  201  or the printer driver  202  on the LCD  60 , and inputs information input by the user through the operating unit  70  to the application  201  or the printer driver  202 . 
     The normal operation of a pull print system having the configuration will be described with reference to  FIG. 6 .  FIG. 6  is a sequence diagram illustrating the normal operation of the pull print system of this embodiment. In the client terminal  2 , when the print job is generated on the basis of an operation of the user, as illustrated in  FIG. 6 , in S 601 , the printer driver  202  transmits the print job to the job management server  3  through the input/output control unit  204 . In the job management server  3 , in S 602 , the input/output control unit  301  receives the print job, and the job managing unit  302  stores the print job in a storage medium, such as the HDD  40 . 
     After operating the client terminal  2  to output the print job, the user operates the image forming apparatus  1 . Accordingly, in S 603 , the image forming apparatus  1  acquires a list (job list) of print jobs from the job managing unit  302  of the job management server  3  through the network, and displays the job list on the display panel  104 . At this time, user authentication or the like is performed to increase security, so that only the print job of the user is acquired. 
     The user operates the display panel  104  and selects a print job to be performed from among the displayed print jobs. Accordingly, in S 604 , the image forming apparatus  1  acquires the selected print job from the job management server  3  through the network and performs image formation output. In the job management server  3 , in S 605 , the print job is output in accordance with access from the image forming apparatus  1  and log information is stored. In the image forming apparatus  1 , in S 606 , the log information is stored as image formation output is performed. At the process of S 605  and S 606 , the log information illustrated in  FIG. 7  is generated in the log managing unit  160  and the log managing unit  303 , and is stored in a storage medium, such as the HDD  40 . 
     The acquisition of the print job may be performed when acquiring the job list. That is, in S 603 , the image forming apparatus  1  acquires the print job and the job list of the print job from the job managing unit  302  of the job management server  3 . The job list is displayed on the display panel  104 , and when the print job is selected by the user, the image forming apparatus  1  extracts the selected print job from among the print jobs stored in the storage medium, and performs image formation output. 
     Next, a characteristic operation of the pull print system of this embodiment will be described with reference to  FIG. 8 . As illustrated in  FIG. 8 , in the client terminal  2  in S 801 , when a print job is generated on the basis of an operation of the user, the printer driver  202  confirms the operation state of the job management server  3  through the input/output control unit  204 . With the confirmation in S 801 , when it is confirmed that the job management server  3  is in the disabled state in S 802 , the printer driver  202  transmits the print job to the image forming apparatus  1 . 
     At the process of S 802 , the printer driver  202  determines to which of the image forming apparatus  1   a  and the image forming apparatus  1   b  the print job will be transmitted and then transmits the print job. An apparatus to which the print job will be transmitted is determined by setting information defined in advance or designation of a user operation. 
     In the image forming apparatus  1 , in S 803 , the input/output control unit  150  receives the print job, and image formation output is performed under the control of the main control unit  110 . As described above, since the system of this embodiment is of pull print system, it is preferable that the process of S 803 , which is an outputting of formed image when a print job is directly input from the client terminal  2  to the image forming apparatus  1 , is performed in accordance with an operation of the user on the image forming apparatus  1 . 
     Under this control, for example, after the input/output control unit  150  receives the print job, the main control unit  110  temporarily stores the print job in a storage medium, such as the HDD  40 . That is, the main control unit  110  functions as a print data storage unit. The main control unit  110  can be formed of reading the print job temporarily stored in the storage medium in accordance with an operation of the user, that is, an operation signal input through the operation display control unit  140 , and performing an image formation output process in accordance with the print job. When image formation output is performed in the image forming apparatus  1 , in S 804 , the log managing unit  160  stores a log into the storage medium. 
     Through S 804 , log information illustrated in  FIG. 9A  is stored in the log managing unit  160 . As illustrated in  FIG. 9A , in the case of the log information of the print job which is directly transmitted from the client terminal  2  to the image forming apparatus  1  and executed, the value “Yes” is input to the item “direct printing”. The value “Yes” in the item “direct printing” is identification information which identifies image formation output performed in accordance with the print job directly input from the client terminal  2 . 
     Thereafter, in S 805 , when the job management server  3  returns from the disabled state, in S 806 , the log managing unit  303  of the job management server  3  accesses the image forming apparatus  1  through the input/output control unit  301 , and inquires about the presence/absence of the log information of the print job (hereinafter, referred to as a direct print job) directly input from the client terminal  2  to the image forming apparatus  1 . When there is the log information of the direct print job, that is, the log information where the value of the item “direct printing” is “Yes”, in S 807 , the log managing unit  303  acquires the log information from the image forming apparatus  1  and stores the log information into the storage medium. 
     When the log information stored in the log managing unit  303  is in the state illustrate in  FIG. 9B  before the process of S 807  is performed, after the process of S 807 , that is, after the log information illustrated in  FIG. 9A  is acquired, the state illustrate in  FIG. 9C  is reached. As illustrated in  FIG. 9C , with regard to the log information of the direct print job, the value “1a” which is a value indicating the execution in the image forming apparatus  1   a  is set to the item “direct printing”. 
     In the image forming apparatus  1 , when the log information of the direct print job is acquired by the job management server  3 , as illustrated in  FIG. 9D , the log managing unit  303  updates the log information such that the value of the item “direct printing” is changed to “collected”. Accordingly, when the job management server  3  acquires the log information concerning the direct print job again, it is possible to avoid the same log information from being acquired double. 
     Next, the operations of the client terminal  2  and the job management server  3  in the overall operation of the system illustrated in  FIG. 8  will be described.  FIG. 10  is a flowchart illustrating the operation of the client terminal  2 . As illustrated in  FIG. 10 , in S 1001 , when a job is generated by an operation of the user in the client terminal  2 , in S 1002 , the printer driver  202  confirms whether or not the job management server  3  is in operation through the network, that is, whether or not a print job is receivable. The process of S 1002  corresponds to the process of S 801  of  FIG. 8 . 
     As the result of the confirmation of S 1002 , when the job management server  3  is in operation (YES in S 1002 ), in S 1003 , the printer driver  202  transmits the print job to the job management server  3  and ends the process. The process of S 1003  corresponds to the process of S 601  of  FIG. 6 . When the job management server  3  is not in operation, that is, when the print job is not receivable (NO in S 1002 ), in S 1004 , the printer driver  202  determines the transmission destination of the print job from among the image forming apparatus  1   a  and the image forming apparatus  1   b.    
     As a method in which the printer driver  202  determines the transmission destination of the print job in S 1004 , the printer driver  202  can acquire the state of the image forming apparatus  1  through the network regularly, and can select an operable apparatus at the timing of S 1004 . The attribute of the print job, such as the type of color/monochrome and duplex printing designation, may be acquired from the print job, and an apparatus according to the attribute can be selected. A plurality of methods may be combined. 
     When the transmission destination of the print job is determined, in S 1005 , the printer driver  202  transmits the print job to the determined transmission destination through the network and ends the process. The process of S 1005  corresponds to the process of S 802  of  FIG. 8 . With this process, even when the job management server  3  is in the disabled state, the print job can be transmitted. 
       FIG. 11  is a flowchart illustrating the operation of the job management server  3 . As illustrated in  FIG. 11 , in S 1101 , when the job management server  3  returns from the disabled state, the log managing unit  303  inquires the image forming apparatus  1  of the presence/absence of the log information through the network in S 1102 . The process of S 1101  corresponds to the process of S 805  of  FIG. 8 , and the process of S 1102  corresponds to the process of S 806  of  FIG. 8 . In the image forming apparatus  1 , the log managing unit  160  transmits a list of stored log information in response to the inquiry from the job management server  3 . 
     In S 1103 , the log managing unit  303  which acquires a list of log information from the image forming apparatus  1  confirms the log information where the item “direct printing” is “Yes” as illustrated in  FIG. 9A , that is, the presence/absence of the log of the direct print job. When there is the direct print job (YES in S 1103 ), in S 1104 , the log information is acquired from the image forming apparatus  1  and stored. The process of S 1104  corresponds to the process of S 807  of  FIG. 8 . 
     The log managing unit  303  repeats the processes from S 1102  to S 1104  for all the image forming apparatuses  1  connected to the network, that is, in this embodiment, the image forming apparatus  1   a  and the image forming apparatus  1   b  (NO in S 1105 ). After the processes from S 1102  to S 1104  are performed for all the image forming apparatuses  1  (YES in S 1105 ), the process ends. 
     Although in  FIG. 11 , a case has been described where the condition of S 1101 , that is, the operation start condition refers to when the job management server  3  returns from the disabled state, the operation may be incorporated as a process in power-on reset of the job management server  3 . That is, the operation of  FIG. 11  is not limited to when the job management server  3  is in the disabled state due to an error or the like, and may be performed when the state where a print job is not receivable is changed to the state where a print job is receivable, such as power-on. 
     In  FIG. 11 , as described as the process of S 1103  and S 1104 , a case where the determination of the direct print job is performed on the job management server  3  side has been described. As another modification, the job management server  3  may acquire all pieces of log information stored in the image forming apparatus  1 , may store only log information which is not stored in the log managing unit  303 , and may discard the remaining log information. 
     The job management server  3  may access the image forming apparatus  1  to acquire only the log information of the direct print job, and the log managing unit  160  of the image forming apparatus  1  may transmit only the log information of the direct print job with the item “direct printing” of “Yes” from among the stored log information to the job management server  3 . The access to the image forming apparatus  1  to acquire only the direct print job can be defined as, for example, a notification (hereinafter, referred to as a return notification) that the job management server  3  returns from the disabled state. That is, when the image forming apparatus  1  receives the return notification from the job management server  3 , the log information of the direct print job may be transmitted to the job management server  3 . In this case, the log managing unit  303  functions as a state notification unit which gives notification of the state where the job management server  3  can receive the print job. 
     As described above, in the pull print system of this embodiment, when the job management server  3  is in the disabled state, the client terminal  2  transmits the direct print job to the image forming apparatus  1 , thereby avoiding output from being disabled. With regard to the log information concerning the direct print job, the image forming apparatus  1  adds information (hereinafter, referred to as a direct printing flag) for identifying image formation output by a print job directly input from the client terminal  2 , like the value “Yes” of the item “direct printing”. 
     When having returned from the disabled state, the job management server  3  accesses the image forming apparatus  1  to acquire log information added with a direct printing flag. Accordingly, log information of image formation output performed by the direct print job while the job management server  3  is in the disabled state is stored in the job management server  3 , such that centralized management of the log information can be performed in the job management server  3 . 
     This embodiment is premised on the pull print system. For this reason, at the timing at which the job management server  3  has returned from the disabled state, there may be a print job on standby in the image forming apparatus  1 , that is, after a print job is directly input from the client terminal  2  to the image forming apparatus  1 , there may be a print job which is not yet subjected to image formation output. In this case, it is preferable that the job management server  3  acquires the print job from the image forming apparatus  1 , and returns to the normal sequence described in  FIG. 6 . The operation of the job management server  3  for enabling the above-described form will be described with reference to  FIG. 12 . 
       FIG. 12  is a flowchart illustrating the operation of the job management server  3  described above. As illustrated in  FIG. 12 , in steps from S 1201  to S 1204 , the same process as from S 1101  to S 1104  of  FIG. 11  is performed. In S 1204 , when the log information concerning the direct print job is acquired, next, in S 1205 , the job managing unit  302  inquires about the presence/absence of an unprocessed and standby print job (hereinafter, referred to as a standby job) in the image forming apparatus  1 . 
     In the image forming apparatus  1 , in response to the inquiry from the job management server  3 , the main control unit  110  notifies the job management server  3  of the presence/absence of a standby job stored in a storage medium such as the HDD  40 . As the result of the notification from the image forming apparatus  1 , when there is a standby job (YES in S 1205 ), the job management server  3  requests the image forming apparatus  1  to transmit the standby job. That is, the job managing unit  302  functions as a print data acquisition requesting unit. 
     When the request from the job management server  3  is received, in the image forming apparatus  1 , the main control unit  110  reads the standby job stored in the storage medium, such as the HDD  40 , and transmits the standby job to the job management server  3 . That is, the main control unit  110  functions as an unprocessed data transmission unit. In the job management server  3 , in S 1206 , the input/output control unit  301  receives the standby job transmitted from the image forming apparatus  1 , and the job managing unit  302  acquires the standby job. Accordingly, as in S 602  of  FIG. 6 , the job managing unit  302  stores the print job. 
     Thereafter, as in the S 1105  of  FIG. 11 , the process of S 1202  to S 1206  repeats until the process is completed for all the image forming apparatuses  1  (NO in S 1207 ), and after the process of S 1202  to S 1206  for all the image forming apparatuses  1  is performed (YES in S 1207 ), the process ends. 
     With this process, the print job on standby is temporarily stored by the job managing unit  302  of the job management server  3 , and thereafter, image formation output is performed by the normal operation illustrated in  FIG. 6 . At the timing at which the job management server  3  has returned, when a print job on standby is not stored as log information in the image forming apparatus  1 , the log information is not collected in the job management server  3  depending on the operation illustrated in  FIG. 8 . Meanwhile, as illustrated in  FIG. 12 , a print job on standby is collected by the image forming apparatus  1 , and centralized management of log information can be performed without omission. 
     According to the embodiment, in the pull print system, it is possible to allow centralized management of log information while the server is in the disabled state. 
     Although the invention has been described with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth.