Abstract:
An image forming apparatus includes a first acquiring unit, a determination unit, a second acquiring unit, and a notifying unit. The first acquiring unit acquires first settable region information on a plane-shaped recording medium in other image forming apparatus. The first settable region information indicates a first settable region on which a registration mark is settable. The determination unit determines a first region based on the first settable region information. The first region is a region on which the registration mark is formable in a cascade printing system including the image forming apparatus and the other image forming apparatus. The second acquiring unit acquires second settable region information on the plane-shaped recording medium. The second settable region information indicates a second settable region on which the registration mark is formable in the plane-shaped recording medium. The notifying unit provides invalidity information indicating the registration mark is possible invalid.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims priority under 35 USC 119 from Japanese Patent Application No. 2010-050230, filed Mar. 8, 2010. 
     BACKGROUND 
     Technical Field 
     This invention relates to an image forming apparatus and a computer readable medium. 
     SUMMARY OF THE INVENTION 
     According to an aspect of the invention, an image forming apparatus includes a first acquiring unit, a determination unit, a second acquiring unit, and a notifying unit. The first acquiring unit acquires first settable region information on a plane-shaped recording medium in other image forming apparatus. The first settable region information indicates a first settable region on which a registration mark is settable. The determination unit determines a first region based on the first settable region information. The first region is a region on which the registration mark is formable in a cascade printing system including the image forming apparatus and the other image forming apparatus. The second acquiring unit acquires second settable region information on the plane-shaped recording medium. The second settable region information indicates a second settable region on which the registration mark is formable in the plane-shaped recording medium. When the second region is not involved in the first region, the notifying unit provides invalidity information indicating the registration mark is possible invalid. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments of the invention will be described in detail based on the following figures, wherein: 
         FIG. 1  is a perspective view of a cascade printing system of an exemplary embodiment of the invention; 
         FIG. 2  is a block diagram of the cascade printing system of the exemplary embodiment of the invention; 
         FIG. 3  is a flowchart to show an example of the operation of the exemplary embodiment of the invention; and 
         FIG. 4  is a flowchart to show an example of the operation of the exemplary embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     (General Configuration) 
     An example using the invention will be discussed below.  FIG. 1  shows an example of a cascade printing system using the invention.  FIG. 1  shows a cascade printing system  10 . The cascade printing system  10  has a function of forming an image on the surface and the back of a continuous sheet of paper of an example of a plane-shaped recording medium using image forming apparatus  12  and  14 . 
     The image forming apparatus  12  is placed upstream in a sheet conveying path and stores a continuous sheet wound like a roll. A continuous sheet P with an image formed on one side in the image forming apparatus  12  is sent to a buffer device  18 . The buffer device  18  bends the continuous sheet being conveyed in the apparatus and has a function of suppressing slack, twist, a floppy state, excessive tension, etc., of the continuous sheet P. 
     A surface and back inversion device  16  is placed downstream from the buffer device  18 . The surface and back inversion device  16  inverts the surface and the back (up and down) of the continuous sheet and sends the sheet P to the downstream image forming apparatus  14 . The image forming apparatus  14  prints on the side opposite to the side of the continuous sheet P printed in the image forming apparatus  12 . The image forming apparatus  14  includes a winding mechanism for winding the continuous sheet where image forming terminates. 
     The image forming apparatus  12  and the image forming apparatus  14  form an image according to electrophotography. That is, although not shown in the figure, each of the image forming apparatus  12  and the image forming apparatus  14  includes a photoconductive drum, an exposure device for exposing for forming an electrostatic latent image on the photoconductive drum, a developing device for developing the electrostatic latent image in toner and forming a toner image, a transfer device for transferring the toner image to a continuous sheet, and a fixing device for fixing the toner image transferred onto the continuous sheet. 
     The image forming apparatus  12  includes a sheet feed device (sheet supply device) for storing a wound continuous sheet and feeding the continuous sheet while unwinding the continuous sheet. The image forming apparatus  14  includes a sheet winding device for winding the continuous sheet where an image is formed. 
     The image forming apparatus  12  and the image forming apparatus  14  are different models and differ in specification. The image forming apparatus  12  is a model that may use a continuous sheet formed with pin feed holes for conveying a sheet on both sides. The image forming apparatus  14  is a model not compatible with a continuous sheet formed with pin feed holes. 
     By the way, to print on both sides of a continuous sheet P in the cascade printing system  10  as illustrated in  FIG. 1 , a registration mark functioning as a mark is used to register the positions of surface and back images. That is, when an image is formed on a first side in the image forming apparatus  12 , a registration mark is formed at the same time. When an image is formed on a second side in the image forming apparatus  14 , the registration mark is optically detected by an optical sensor of the image forming apparatus  14  and an image is formed in the image forming apparatus  14  on the second side matched with the position of the image formed on the first side based on the registration mark. 
     The registration mark functions as display indicating position information in the continuous sheet P detected by the downstream image forming apparatus  14  and is formed in an inconspicuous location in the proximity of a margin of the continuous sheet or the like. The area in which the registration mark may be formed in the image forming apparatus  12  and the area in which the registration mark may be detected in the image forming apparatus  14  do not match. This is caused by whether or not the apparatus is compatible with a continuous sheet formed with pin feed holes. 
     This point is discussed below: A continuous sheet formed with pin feed holes and a continuous sheet formed with no pin feed holes differ in the dimension between the margin of the sheet and the image forming area. Thus, the image forming apparatus  12  and  14  differ in handling the registration mark and the area in which the registration mark may be formed in the image forming apparatus  12  and the area in which the registration mark may be detected in the image forming apparatus  14  do not become the same. 
     The registration mark has the two modes: One in which the registration mark is formed on the side where the image forming apparatus  12  forms an image and the other in which the registration mark is formed on the back side of the side. The mode may be selected by setting operation as operation of a control panel described later. 
     The image forming apparatus  12  includes an operation panel  20 . The operation panel  20  is a touch panel display and an interface for making various settings of the image forming apparatus  12  and operating the image forming apparatus  12 . The image forming apparatus  14  includes an operation panel  21 . The operation panel  21  is a touch panel display and an interface for making various settings of the image forming apparatus  14  and operating the image forming apparatus  14 . 
     (Configuration of Control System) 
       FIG. 2  shows the configuration of a control system of the cascade printing system  10  as shown in  FIG. 1 . The image forming apparatus  12  includes a controller section  30 , a transmission and reception processing section  31 , an image forming processing management section  32 , a resource management processing section  33 , and a sheet information data storage section  34 . The controller section  30  includes a function as a computer and has a function of controlling the operation of the image forming apparatus  12 . The transmission and reception processing section  31  has a function of transmitting and receiving (namely, communicating) data to and from a controller section  40 , the operation panel  20 , and the operation panel  21  through a communication line  50  of a LAN, etc. 
     The image forming processing management section  32  manages the processing operation in the image forming apparatus  12  in the image forming operation. For example, the timing of exposure to the photoconductive drum, the transfer timing of a toner image, and the like are controlled by a control signal output from the image forming processing management section  32 . The resource management processing section  33  manages sheet information concerning a continuous sheet, various set conditions, etc. The sheet information handled in the resource management processing section  33  also contains information concerning the area in which the above-described registration mark on a continuous sheet may be formed (may be detected). The resource management processing section  33  also executes processing described later with reference to  FIG. 3 . In the resource management processing section  33 , a setting section  331  for performing various types of setting processing in  FIG. 3 , an acquisition section  332  for performing various types of acquisition processing, a comparison section  333  for making a comparison on which various determinations are based, and an informing section  334  for performing processing to perform informing processing are implemented as software. 
     The sheet information data storage section  34  stores sheet information handled by the resource management processing section  33 . In addition, the controller section  30  includes a CPU, a memory area, and an interface function to function as a computer. 
     The controller section  40  includes a similar configuration to that of the controller section  30 . However, since the image forming apparatus  12  and  14  are different models, fine control and handled data differ because of the model difference. However, the basic function of each function section is the same as that of the controller section  30  described above and therefore the controller section  40  will not be discussed. 
     (Operation Example) 
     An example of the operation of the configuration shown in  FIG. 1  will be discussed.  FIG. 3  is a flowchart to show an example of the operation. The flowchart of  FIG. 3  is executed in the resource management processing section  33  of the controller section  30  of the image forming apparatus  12  placed upstream in the sheet convey path. 
     A program for executing the flowchart of  FIG. 3  is stored in a memory area (for example, in a hard disk unit forming the sheet information data storage section  34 ) in the controller section  30  and is read to an appropriate memory area for execution. The program may be stored in a server or an appropriate storage medium and be provided therefrom. 
     To use the system in  FIG. 1 , the operation panel  20  or  21  is operated by an operator and various settings are made. In the system in  FIG. 1 , in operation control, the controller section  30  (see  FIG. 2 ) of the upstream image forming apparatus  12  becomes the host and thus setting made by operating the operation panel  21  is sent to the controller section  30  through the communication line  50 . 
     When operation of setting mentioned above is started (step S 301 ), the setting operated by the operator is made (step S 302 ). Next, whether or not the system is a dual association system is determined (step S 303 ). If the system is a dual association system as shown in  FIG. 1 , the process goes to step S 304 ; if the image forming apparatus is used singly, the process goes to step S 311 . 
     At step S 304 , whether or not setting operation of common set conditions is performed is determined. The common set conditions are conditions of settings which are previously provided and are stored in the sheet information data storage section  34  and may be used by the image forming apparatus  12  and  14  in common. The common set conditions contain a condition for setting a common area in which a registration mark may be formed in both apparatus. A plurality of common set conditions are previously provided considering models predicted in combination. 
     If setting operation of the common set conditions is performed at step S 302 , the process goes from step S 304  to step S 305  and the common set condition is acquired. At this time, one condition of candidates (for example, the highest one in the list) is selected and is acquired. After step S 305 , information concerning the continuous sheet to be used is acquired (step S 306 ). The information concerning the continuous sheet contains information about the range in which a registration mark may be formed on the continuous sheet. Then, the area in which the registration mark may be formed (settable area) in the cascade printing system  10  in  FIG. 1  is set based on the description acquired at step S 305  (step S 307 ) and the process goes to step S 313  described later. 
     The process returns to step S 304  and if the common set conditions are not set, the process goes to step S 308 . At step S 308 , information concerning the continuous sheet to be used is acquired and next, information of the area in which the registration mark may be detected (settable area) in the image forming apparatus  14  of another apparatus forming the cascade printing system  10  is acquired from the image forming apparatus  14  (S 309 ). The area in which the registration mark may be formed (settable area) in the cascade printing system  10  is determined based on the acquired description (step S 310 ). 
     For example, at step S 310 , a comparison is made between information of the area in which the registration mark may be formed, set by the operator and the range of the position of the registration mark that may be handled by the image forming apparatus  14  acquired from the image forming apparatus  14 , and a common area is extracted therefrom and is set to the area in which the registration mark may be formed (settable area) in the cascade printing system  10 . 
     The process returns to step S 303  and if the system is a cascade printing system, information of the continuous sheet to be used is acquired (step S 311 ) and next the area in which the registration mark may be formed (settable area) in the image forming apparatus (in this case, the image forming apparatus  12 ) is acquired (step S 312 ) and the processing is terminated (step S 316 ). This processing flow is the same as that of a usual image forming apparatus. 
     If step S 307  or S 310  is executed, the process goes to step S 313 . At step S 313 , a comparison is made between the range in which the registration mark may be formed on the continuous sheet obtained from the acquired information of the continuous sheet and the settable area (the area in which the registration mark may be formed, seen from the cascade printing system side) determined at step S 307  or S 310 , and whether or not the former is contained in the latter is determined. 
     If the determination at step S 313  is NO, the possibility that the positioning mark will not normally function occurs. If the positioning mark does not normally function, the function of registering the image position on the surface and the back of the continuous sheet. 
     At step S 313 , if the range in which the registration mark may be formed on the continuous sheet is contained in the area in which the registration mark may be formed (in the settable area) seen from the cascade printing system  10  side, the positioning mark functions effectively in the cascade printing system  10  and thus the processing is terminated (step S 316 ). 
     On the other hand, at step S 313 , if the range in which the registration mark may be formed on the continuous sheet is not contained in the area in which the registration mark may be formed, seen from the cascade printing system  10  side, there is a possibility that a defective condition may occur in the double-sided print operation as described above and thus the process goes to step S 314 . At step S 314 , whether or not the common set conditions are set at step S 302  is determined again as at step S 304 . 
     If the common set conditions are set, step S 305  is again executed, an unselected common setting condition at this point in time is selected, and processing of step S 306  and the later is repeated. 
     When the process goes from step S 314  to step S 305 , if an unselected common setting condition does not exist, an error message of “common setting condition that may be used does not exist” or the like is provided (not shown in the figure) and the process returns to S 302 . In this case, setting is again made from the beginning. 
     If the common set conditions are not set at step S 314 , the process goes to step S 315  and an error message is provided. At step S 315 , display to the effect that an error exists in the setting concerning the forming position of the registration mark is produced on the operation panel operated by the operator. If an error message is provided at step S 315 , the process returns to step S 302  and setting is again made from the beginning. 
     (Priority) 
     When two image forming apparatus are used in combination, if an area in which a registration mark may be formed is set so that the registration mark functions in both the two apparatus, it does not match the range in which the registration mark may be formed on a used continuous sheet in some cases. In the embodiment, the matching is determined at step S 313  and if the matching is not ensured, an error message is provided at step S 315 . 
     Accordingly, the operator is informed of occurrence of a defective condition that the registration mark does not effectively function and it is made possible for the operator, to grasp existence of a problem in setting of the registration mark. 
     That is, when different models of image forming apparatus are used in combination in the image forming system, whether or not there is a possibility that the registration mark will not effectively function is determined (step S 313 ) and the user is informed of the determination result (step S 315 ). Thus, fruitless print operation wherein double-sided printing is not effectively performed may be circumvented. 
     According to processing of step S 304  and the later, preset setting that may be used in common in the image forming apparatus  12  and  14  is selected. Thus, if dual association connection of different models is made, two image forming apparatus are operatively associated and the operation in which the registration mark effectively functions may be set without performing intricate setting operation separately for each image forming apparatus. 
     (Another Processing Example) 
       FIG. 4  is a flowchart to show one of application examples of the processing in  FIG. 3 . In the processing in  FIG. 4 , after step S 303 , whether or not the two image forming apparatus making up the system are the same model is determined (step S 303 ′). In the example, if the two image forming apparatus are the same model, the process goes to step S 311 ; otherwise, the process goes to step S 304 . Others are the same as those in  FIG. 3 . According to the processing in  FIG. 4 , a dual association system using the same model may also be covered. 
     (Others) 
     Each common set condition may be provided for each combination pattern of models to be combined, table data may be stored, and the common set condition appropriate for the combined models may be selected from the table data. 
     As the functions of the registration mark, in addition to a mark used for registration at double-sided printing time, functions of informing the downstream image forming apparatus of position information in a continuous sheet such as a function of specifying the fold position, a function of specifying the position of staple processing, and a function of specifying the cut portion in postprocessing after image forming may be named. Any one or two or more of the functions may be used. 
     The common set conditions may be generated based on internal information of the image forming apparatus  12  and  14 . In this case, the resource management processing section  33  performs the following processing: First, the resource management processing section  33  acquires information concerning the area in which a registration mark may be formed in the image forming apparatus  12  from the sheet information data storage section  34  and further acquires information concerning the area in which the registration mark may be detected in the image forming apparatus  14  from sheet information data storage section  44 . A common area in the two areas is extracted and is adopted as the common setting condition. 
     INDUSTRIAL APPLICABILITY 
     The invention may be used for the art of forming an image on a continuous record medium using image forming apparatus of different models. 
     The foregoing description of the exemplary embodiment of the present invention has been provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and various will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, thereby enabling other skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.