Patent Publication Number: US-2012038942-A1

Title: Image forming apparatus and image forming method

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority from Provisional U.S. Applications 61/372,423 filed on Aug. 10, 2010, the entire contents of which are incorporated herein by reference. 
    
    
     FIELD 
     Embodiments described herein relate generally to an image forming apparatus and an image forming method. 
     BACKGROUND 
     A multi function peripheral (hereinafter referred to as an MFP) of related art can print an image on a sheet based on digital book data as one of image data. 
     In an image forming apparatus including the MFP of the related art, in order to form a book from the digital book data, an optimizing process (for example, magazine sort, 2-in-1 process) to optimize the digital book data, two-sided printing, saddle stitch and the like are required to be set as a print mode. 
     However, the user is required to operate a control panel and to perform the various settings one by one. Accordingly, to form a book from digital book data by using the image forming apparatus of the related art is very troublesome for the user. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic structural view showing an image forming apparatus of a first embodiment. 
         FIG. 2  is a block diagram showing an electrical structure of the image forming apparatus of the first embodiment. 
         FIG. 3  is a flowchart showing an image forming method of the first embodiment. 
         FIG. 4  is a view showing a setting screen of a digital book print mode displayed on a control panel device. 
         FIG. 5  is an explanatory view for explaining magazine sort. 
         FIG. 6  is an explanatory view for explaining a 2-in-1 process. 
         FIG. 7  is an explanatory view for explaining a saddle stitch. 
         FIG. 8  is a flowchart showing an image forming method of a second embodiment. 
         FIG. 9  is a view showing a selection screen of digital book print modes displayed on a control panel device. 
     
    
    
     DETAILED DESCRIPTION 
     In general, according to one embodiment, an image forming apparatus includes a determination part, a display part, an image processing part, an image forming part, an inversion conveyance part, a finishing part and a main control part. The determination part determines whether image data is digital book data. If the determination part determines that the image data is the digital book data, the display part automatically displays a digital book print mode for forming a book from the digital book data. The image processing part arithmetically processes the digital book data. The image forming part forms an image based on the digital book data on a sheet. The inversion conveyance part inverts the sheet on one side of which the image is formed by the image forming part and conveys the sheet to the image forming part. The finishing part finishes the sheet on which the image is formed by the image forming part. The main control part includes the determination part and the image processing part, and automatically controls at least one of the image processing part, the inversion conveyance part and the finishing part specified based on the digital book print mode displayed on the display part. 
     According to another embodiment, an image forming method includes determining whether image data is digital book data, displaying a digital book print mode, controlling at least one of an image processing part, an inversion conveyance part and a finishing part, and forming a book. The digital book print mode is a digital book print mode for forming a book from the digital book data, and is automatically displayed if the determination is that the image data is the digital book data. At least one of the image processing part, the inversion conveyance part and the finishing part is automatically controlled based on the displayed digital book print mode. Here, the image processing part arithmetically processes the digital book data. The inversion conveyance part inverts a sheet on one side of which an image is formed by an image forming part to form the image based on the digital book data on a sheet, and conveys the sheet to the image forming part. The finishing part finishes the sheet on which the image is formed by the image forming part. The book is formed by an image forming apparatus including the image processing part, the inversion conveyance part and the finishing part which are controlled based on the digital book print mode, and the image forming part. 
     According to another embodiment, an image forming method includes determining whether image data is digital book data, displaying a digital book print mode, controlling an image processing part, an inversion conveyance part and a finishing part, and forming a book. The digital book print mode is a digital book print mode for forming a book from the digital book data, and is automatically displayed if the determination is that the image data is the digital book data. The image processing part, the inversion conveyance part and the finishing part are automatically controlled based on the displayed digital book print mode. Here, the image processing part performs an optimum arithmetic processing for forming the book on the digital book data. The inversion conveyance part inverts a sheet on one side of which an image is formed by an image forming part to form the image based on the digital book data on a sheet, and conveys the sheet to the image forming part. The finishing part includes a saddle stitch part that staples a center part of the sheets on which the image is formed by the image forming part and folds the sheets in two along the center part of the sheet. The book is formed by an image forming apparatus including the image processing part, the inversion conveyance part and the finishing part which are controlled based on the digital book print mode, and the image forming part. 
     Hereinafter, an image forming apparatus and an image forming method of embodiments will be described. 
     First Embodiment 
       FIG. 1  is a schematic structural view showing an image forming apparatus of a first embodiment. An image forming apparatus  10  shown in  FIG. 1  includes an MFP (Multi Function Peripheral or Multi Function Printer)  11  and a finisher  12  as a finishing part. 
     The MFP  11  includes a scanner part  13 , an image forming part  14  and a sheet conveyance part  15 . The scanner part  13  reads a document image, and forms image data based on the read image. 
     The scanner part  13  includes an auto document feeder  16  (hereinafter referred to as an ADF  16 ) and a scanner device  17 . 
     The ADF  16  feeds a document to the scanner device  17 . The scanner device  17  reads the document image and forms the image data based on the read image. 
     The scanner device  17  includes a document glass  17   a  on which the document fed from the ADF  16  is placed, an optical unit  17   b  to irradiate the document with light and condenses reflected light from the document, and a CCD scanner unit  17   c  to read the light from the optical unit  17   b . The scanner device  17  reads the document image by these components. 
     The image forming part  14  includes a printer device  25  including a photoconductive drum  18 , a charging device  19 , a developing device  20 , a transfer charger  21 , a peeling charger  22 , a cleaner  23  and a charge removing LED  24 . Besides, the image forming part  14  includes a laser device  26 . The charging device  19 , the developing device  20 , the transfer charger  21 , the peeling charger  22 , the cleaner  23  and the charge removing LED  24  constituting the printer device  25  are provided around the photoconductive drum  18  in this order in an arrow q rotation direction of the photoconductive drum  18 . 
     The charging device  19  uniformly charges a surface of the photoconductive drum  18 . The laser device  26  irradiates laser light to the photoconductive drum  18 , the surface of which is charged, based on the image data formed by the scanner part  13  or digital book data captured into the image forming apparatus  10  through an after-mentioned external connection part, and forms an electrostatic latent image. The developing device  20  supplies toner to the surface of the photoconductive drum  18  on which the electrostatic latent image is formed, and forms a toner image based on the electrostatic latent image. The transfer charger  21  transfers the toner image formed on the surface of the photoconductive drum  18  onto a sheet. By this, the image forming part  14  forms the toner image on the sheet. Incidentally, the peeling charger  22  performs AC corona discharge, and peels the sheet, which adhered to the photoconductive drum  18  at the time of transfer, from the photoconductive drum  18 . The cleaner  23  removes toner remaining on the surface of the photoconductive drum  18  after the toner image is transferred. The charge removing LED  24  removes the electric charge of the surface of the charged photoconductive drum  18 . 
     The image forming part  25  includes a fixing device  27 . The fixing device  27  includes a heat roller  28  and a press roller  29 . In the fixing device  27 , the heat roller  28  and the press roller  29  nip and convey a sheet, heat and press the toner image formed on the sheet, and fix the toner image on the sheet. 
     The image forming part  14  forms the toner image on the sheet, fixes the toner image and prints the image based on the image data or the digital book data on the sheet. 
     The sheet conveyance part  15  conveys a sheet supplied from cassette mechanisms  30   a  to  30   d  containing sheets of different sizes or a sheet supplied from a manual feed mechanism  31  including a paper feed tray  31   a  to a specified portion. The sheet conveyance part  15  includes an inversion conveyance part  32  and an aligning roller  33 . 
     The inversion conveyance part  32  includes an upper and lower paper discharge roller pair  34 , and an inversion part  35 . The upper and lower paper discharge roller pair  34  negatively rotate, and convey the sheet on one side of which an image is printed to the inversion part  35 . The inversion part  35  inverts the sheet conveyed by the upper and lower paper discharge roller pair  34 , and again conveys the sheet to the image forming part  14 . That is, the inversion conveyance part  32  inverts the sheet so that an image is formed on the other side of the sheet on one side of which an image is formed, and conveys the sheet to the image forming part  14 . 
     The aligning roller  33  aligns a leading edge of the sheet supplied from one of the cassette mechanisms  30   a  to  30   d , the manual paper feed mechanism  31  and the inversion conveyance part  32 , and conveys the sheet to the photoconductive drum  18  in synchronization with the toner image. 
     Besides, the MFP  11  includes a paper sensor  36  and a sheet discharge unit. The paper sensor  36  is provided downstream of the fixing device  27 , and detects the leading edge of the sheet. The sheet discharge unit is the upper and lower paper discharge roller pair  34  included in the inversion conveyance part  32 , and these positively rotate, so that the sheet on one side or both sides of which the image is formed is discharged to a paper discharge part  37  of the MFP  11  or the finisher  12  attached to the MFP  11 . 
     Incidentally, the MFP  11  includes a gate mechanism  38 . The gate mechanism  38  is a mechanism to discharge a sheet in a direction toward either of the paper discharge part  37  and the finisher  12 . The upper and lower paper discharge roller pair  34  as the sheet discharge unit discharge the sheet on which the image is printed in the direction determined by the gate mechanism  38 . 
     The finisher  12  is disposed adjacently to the MFP  11 . The finisher  12  is a paper discharge mechanism of an option of the MFP  11 , and finishes the sheet on which an image is printed by the image forming part  14  and which is discharged from the MFP  11 . For example, the finisher  12  shown in  FIG. 1  includes, as a finishing mechanism, a staple part  39  to staple a sheet bundle, a saddle stitch part  40  to fold a sheet in two and to staple a specified position of a fold line, and a cutter part  41  to form a cut line for forming a heading tag in the sheet. 
     The finisher  12  includes a paper discharge tray  42  to which the sheet stapled or sorted by the staple part  39  is discharged, and a fixed tray  43 , and includes a paper discharge tray  44  to which a sheet bundle folded in two by the saddle stitch part  40  is discharged. 
     The staple part  39  includes an inlet roller  45 , a paper feed roller  46 , a stand-by tray  47 , a processing tray  48 , a vertical alignment roller  49 , a stapler  50  and a conveyance belt  51 . 
     The inlet roller  45  receives the sheet discharged by the upper and lower paper discharge roller pair  34  as the sheet discharge unit of the MFP  11  through the cutter part  41  and a conveyance roller  52  of the finisher. The inlet roller  45  sends the received sheet in one of dotted line arrow directions shown in the drawing. For example, when the inlet roller  45  sends the received sheet to the paper feed roller  46 , the paper feed roller  46  sends the sheet received from the inlet roller  45  to the stand-by tray  47 . 
     The stand-by tray  47  stacks sheets and has an openable structure. When a specified number of sheets are stacked, the stand-by tray  47  is opened, and the sheets drop to the processing tray  48  by their own weight or an operation of a drop assistant member. The processing tray  48  is disposed below the stand-by tray  47 , and stacks the sheets dropped from the stand-by tray  47 . 
     The sheets stacked on the processing tray  48  are guided to the stapler  50  by the vertical alignment roller  49  and are stapled. The processing tray  48  aligns and stacks the sheets while the stapler  50  staples the sheets. 
     The conveyance belt  51  conveys the stapled sheets to the paper discharge tray  42 . The sheets conveyed by the conveyance belt  51  are discharged to the paper discharge tray  42  through a discharge port  53 . The paper discharge tray  42  moves up and down as indicated by an arrow in the drawing, and receives the sheets. 
     The finisher  12  can discharge the sheets to the paper discharge tray  42  without stapling. In this case, the sheets on the stand-by tray  47  are not dropped to the processing tray  48 , but are discharged to the paper discharge tray  42  through the discharge port  53 . Besides, the finisher  12  includes an aligning device to align the conveyed sheets in the width direction, and can sort and discharge the sheets by using the aligning device. Further, in the finisher  12 , when no finishing in addition to stapling is performed, the sheet conveyed from the MFP  11  is discharged to the paper discharge tray  42  or the fixed tray  43  as it is. 
     The saddle stitch part  40  includes a stack tray  54 , a guide belt  55 , a stapler  56 , a folding roller pair  57 , a blade  58  and a discharge roller pair  59 . 
     The stack tray  54  receives sheets conveyed from the MFP  11  through a paper path  60  in the finisher  12 . The sequentially conveyed sheets are stacked on the stack tray  54  and become a sheet bundle. 
     The guide belt  55  conveys the sheet bundle formed on the stack tray  54  to the stapler  56 . When a center part of the sheet bundle reaches the stapler  56 , the guide belt  55  once stops, and the stapler  56  staples the center part of the sheet bundle. Besides, the guide belt  55  lowers the stapled sheet bundle so that the center part of the sheet bundle stops at a position of a nip point of the folding roller pair  57 . 
     When the sheet bundle is lowered to this position, the blade  58  arranged at a position opposite to the folding roller pair  57  projects the center part of the sheet bundle to the nip point of the folding roller pair  57 , and pushes the sheet bundle into a space between the folding roller pair  57 . The folding roller pair  57  rotate while folding and nipping the sheet bundle, and fold the sheet bundle in two. The sheet bundle folded in two is conveyed by the discharge roller pair  59  as indicated by an arrow in the drawing, and is discharged to the paper discharge tray  44 . 
     A press mechanism  61  to press the sheet or the sheet bundle folded in two and a stopper  62  to receive the discharged sheet or sheet bundle are provided in the vicinity of the paper discharge tray  44 . 
     Incidentally, the finisher  12  includes guide rollers  63   64  to guide the sheet discharged from the MFP  11  along the paper path  60 . Besides, the finisher  12  includes, at an exit of the conveyance roller  52 , a gate  65  to convey the sheet discharged from the MFP  11  to the staple part  39  side or the saddle stitch part  40  side. The gate  52  is switched so that the sheet is conveyed to the staple part  39  side or the saddle stitch part  40  side. 
     The cutter part  41  is arranged between, for example, the MFP  11  and the staple part  39 . Incidentally, the arrangement position of the cutter part  41  is not limited to the illustrated position, and may be any position as long as the position is located upstream of the saddle stitch part  40 . 
     The cutter part  41  forms a U-shaped cut line in the center of the sheet in the conveyance direction. When the cut line is formed by the cutter part  41 , and when the sheet is folded in two by the saddle stitch part  40 , an area defined by the cut line rises, and a heading tag is formed. 
     Incidentally, since the cutter part  41  is for forming the heading tag, when formation of the tag is not required, the sheet sent from the MFP  11  passes through the cutter unit  41  without formation of the cut line. 
       FIG. 2  is a block diagram showing an electric structure of the image forming apparatus  10  of the first embodiment. The image forming apparatus  10  includes a main control part  70  to control the whole apparatus. The main control part  70  includes a CPU, and includes an image processing part  71  to arithmetically process digital book data and image data formed by the scanner part  13 , a determination part  72  to determine whether image data is digital book data, and an inner storage device including a ROM  73 , a RAM  74  and a page memory  75 . 
     The image data formed by the scanner part  13 , the image data or the digital book data received from the outside of the image forming apparatus  10 , or the like is once stored in the page memory  75 . The image processing part  71  arithmetically processes the image data or the digital book data stored in the page memory  75 , and again stores in the page memory  75 . 
     The ROM  73  stores a control program for controlling the image forming apparatus  10 . The image forming apparatus  10  is controlled in accordance with the control program. 
     The RAM  74  stores information relating to a digital book print mode. 
     The main control part  70  is connected with the scanner part  13 , the ADF  16 , the image forming part  14 , the inversion conveyance part  32 , a control panel  76 , an external connection part  77  and a finisher control part  78 , and controls these. 
     The control panel  76  includes a display part  79  formed of, for example, a touch panel. A user operates the control panel  76 , and can give various instructions for printing to the image forming apparatus  10 . 
     The external connection part  77  enables transmission and reception of various data between the image forming apparatus  10  and the outside of the apparatus  10 , and captures the digital book data, the image data or the like into the image forming apparatus  10  from the outside of the apparatus  10 . The external connection part  77  connects the image forming apparatus  10  to a network such as, for example, the Internet, and connects the image forming apparatus  10  and the network such as the Internet so as to enable mutual communication. The interface for connection in this case is Bluetooth (registered trademark), wireless LAN or the like. Besides, the external connection part  77  may be a terminal for connecting the external storage device such as a flash memory and the image forming apparatus  10  so as to enable mutual communication. 
     The finisher control part  78  is connected to the staple part  39 , the saddle stitch part  40  and the cutter part  41  of the finisher  12 , and controls these. Since the finisher control part  78  is connected to the main control part  70 , the MFP  11  and the finisher  12  operate in cooperation with each other. 
     The control of the saddle stitch part  40  by the finisher control part  78  includes control of the stapler  56 , control of the blade  58 , and rotation control of the folding roller pair  57  and the discharge roller pair  59 . 
     In the image forming apparatus  10  shown in  FIG. 2 , if the determination part  72  determines that image data is digital book data, the image process ing part  71  performs an optimum arithmetic processing for forming a book from the digital book data. The optimum arithmetic processing is, for example, magazine sort or 2-in-1 process (process of converting digital book data of two pages into digital book data of one page). A specific example of these processes will be described later. 
     The display part  79  of the control panel  76  automatically displays a digital book print mode for forming a book from digital book data. 
     When the digital book print mode is displayed on the display part  79  of the control panel  76 , the control part  70  controls at least one of the image processing part  71 , the inversion conveyance part  32  and the finisher control part  78  so that various processes specified in the displayed digital book print mode are executed. 
     Next, an image forming method of the first embodiment will be described with reference to  FIG. 3 .  FIG. 3  is a flowchart showing the image forming method of the first embodiment. 
     First, the determination part  72  of the main control part  70  determines whether the image data to be printed is the digital book data (Act  101 ). This determination is automatically performed when the digital book data is captured into the image forming apparatus  10  through the external connection part  77 . Besides, when the digital book data is previously stored in the page memory  75 , the determination is performed when the user operates the control panel  76  and selects printing of the digital book data. 
     When the digital book data is captured into the image forming apparatus  10  through the external connection part  77 , the digital book data is stored in the page memory  75 . 
     If the determination is that the image data to be printed is not the digital book data (Act  101 , NO), the main control part  70  sets a normal print mode (Act  102 ). The setting of the normal print mode may be suitably performed by user&#39;s operation of the control panel  76 . 
     If the determination is that the image data to be printed is the digital book data (Act  101 , YES), the main control part  70  reads information relating to the digital book print mode from the RAM  74 , and automatically displays a setting screen of the digital book print mode as shown in  FIG. 4  on the display part  79  of the control panel  76  (Act  103 ). 
     The digital book print mode for printing the digital book data is displayed on the setting screen of the digital book print mode shown in  FIG. 4 . The digital book print mode includes optimum arithmetic processing to form a book from digital book data, for example, magazine sort and 2-in-1 process, two-sided printing, and saddle stitch. 
     Incidentally, the digital book print mode is displayed on the setting screen of the digital book print mode shown in  FIG. 4 , and further, a selection request for a sheet size to be printed and a selection request for a page range of digital book data to be printed are displayed for the user. 
     The user specifies the sheet size and the page range (Act  104 ) in response to the selection requests for the sheet size and the page range at Act  103 . The user operates the control panel  76  so that this specification is performed. 
     When the sheet size and the page range are specified, the main control part  70  controls the sheet conveyance part  15  to take out a sheet of the specified sheet size from one of the cassette mechanisms  30   a  to  30   d , and fetches the digital book data within the specified page range from the page memory  75 . 
     Next, the main control part  70  sets the digital book print mode in the image forming apparatus  10  (Act  105 ) based on the digital book print mode displayed on the display part  79  of the control panel  76  at Act  103 . When the digital book print mode shown in  FIG. 4  is set, the main control part  70  controls the main processing part  71 , the inversion conveyance part  32  and the finisher control part  78 . 
     When the digital book print mode is set, the main control part  70  controls the image processing part  71 . The controlled image processing part  71  performs, as the optimum arithmetic processing to form the book from the data, the magazine sort and the 2-in-1 process on the digital book data. 
       FIG. 5  is a view for explaining the magazine sort. As shown in  FIG. 5 , when the magazine sort is set as the optimum arithmetic processing, the image processing part  71  rearranges the digital book data having the page number of 1 to n as described below. 
     First, the image processing part determines whether the page number (n) of the final page (n-th page) is a multiple of 4. 
     Next, digital book data which becomes blank sheets of k pages (k=0 or 1 or 2 or 3) is added to the final page of the digital book data, so that the total page number of the digital book data and the digital book data which becomes the blank sheets becomes a multiple of 4. When n is the multiple of 4, k is 0, and when n is not the multiple of 4, k is one of 1, 2 and 3. 
     As described below, the magazine sort is performed on temporal digital book data in which the digital book data which becomes the blank sheets is appropriately added to the digital book data. 
     As shown in  FIG. 5 , in the magazine sort, page data arranged in order of 1, 2, 3, 4, . . . , n+k−3, n+k−2, n+k−1, n+k is rearranged in order of n+k, 1, 2, n+k−1, n+k−2, 3, 4, n+k−3 . . . . 
     The digital book data rearranged in this way is again stored in the page memory  75 . 
     Incidentally, the magazine sort is performed when the 2-in-1 process is set as another optimum arithmetic processing. When a 4-in-1 process (process of converting digital book data of four pages into digital book data of one page) is set as another similar optimum arithmetic processing, the magazine sort is performed as described below. 
     That is, first, a determination is made as to whether the page number (n) of the final page (n-th page) is a multiple of 8, and blank pages are appropriately added so that the whole page number becomes the multiple of 8, and the temporal digital book data is formed. 
     Thereafter, page data arranged in order of 1, 2, 3, 4, 5, 6, 7, 8 . . . , n+k−7, n+k−6, n+k−5, n+k−4, n+k−3, n+k−2, n+k−1, n+k has only to be rearranged in order of n+k−1, n+k, 1, 2, 3, 4, n+k−3, n+k−2, n+k−5, n+k−4, 5, 6, 7, 8, n+k−7, n+k−6, . . . . 
       FIG. 6  is a view for explaining the 2-in-1 process. As shown in  FIG. 6 , when the 2-in-1 process is set as an optimum arithmetic processing, the image processing part  71  sequentially fetches the digital book data, on which the magazine sort is performed, from the page memory  75  in units of two pages from the first page, converts digital book data of two pages fetched at one time into digital book data of one page, and stores in the page memory  75 . Incidentally, when the data is stored in the page memory  75 , a contraction process is performed so that the digital book data of two pages has the same size as the size of each page of the digital book data before the 2-in-1 process is performed. 
     When the 4-in-1 process is set as the optimum arithmetic processing, data is fetched from the page memory  75  in units of four pages from the first page, and digital book data of four pages fetched at one time is converted into digital book data of one page and is stored in the page memory  75  after the contraction process is performed. 
     When the digital book print mode is set at Act  105 , or the normal print mode is set at Act  102 , the main control part  70  starts printing in accordance with the setting (Act  106 ). 
     At Act  106 , when the digital book print mode is set, the main control part  70  controls the inversion conveyance part  32  so that the images based on the arithmetically processed digital book data are printed on both sides of the sheet of the specified size in the image forming part  14 . The image forming part  14  prints the images based on the arithmetically processed digital book data on both sides of the sheet by the controlled inversion conveyance part  32 . 
     Further, when the images based on the arithmetically processed digital book data are printed on both sides of the sheet, the main control part  70  controls the finisher control part  78  so that saddle stitch is performed to a bundle of sheets on both sides of each of which the images are printed based on the arithmetically processed digital book data. 
     When the finisher control part  78  is controlled, as shown in  FIG. 7 , the saddle stitch part  40  staples the sheet bundle by driving a C-shaped sheet binding member  81  into a center part of a sheet bundle  80 , and pushes the center part of the sheet bundle  80  into a space between the folding roller pair  57  by the blade  58 . 
     When the folding roller pair  57  fold the sheet bundle, the sheet bundle folded in two is conveyed by the discharge roller pair  59  and is discharged to the paper discharge tray  44 . 
     The saddle stitch is performed to the sheet bundle as stated above, so that a book is formed from the digital book data. 
     According to the image forming apparatus and the image forming method of the embodiment described above, when the determination is that the image data to be printed is the digital book data, the digital book print mode for forming the book from the digital book data is automatically displayed on the display part  79  of the control panel  76 , and this mode is automatically set to the image forming apparatus  10 . Accordingly, the user can easily print the digital book and forms the book. 
     Second Embodiment 
     Since the structure of an image forming apparatus of a second embodiment is the same as the image forming apparatus  10  shown in  FIG. 1 , the description thereof is omitted, and an image forming method of the second embodiment will be described below. 
     The image forming method of the second embodiment is different from the image forming method of the first embodiment in that plural digital book print modes are stored in a RAM  74 , and the user can select one print mode from the plural digital book print modes. This method will be described below. 
       FIG. 8  is a flowchart showing the image forming method of the second embodiment. 
     First, similarly to the image forming method of the first embodiment, a main control part  70  determines whether image data to be printed is digital book data (Act  201 ). When the determination is that the image data is not the digital book data (Act  201 , NO), the main control part  70  sets a normal print mode (Act  202 ). 
     At Act  201 , when the determination is that the image data is the digital book data (Act  201 , YES), the main control part  70  reads information relating to the plural digital book print modes stored in the RAM  74 , and automatically displays the plural digital book print modes as shown in  FIG. 9  on a display part  79  of a control panel (Act  203 ). 
     In  FIG. 9 , as the digital book print modes, a mode  1  and a mode  2  are displayed. The mode  1  is a mode similar to the print mode described in the first embodiment. The mode  2  is a mode in which the saddle stitch of the mode  1  is replaced by saddle folding. 
     The user selects one print mode from the plural digital book print modes displayed as in  FIG. 9 . The user operates the control panel  76  so that this selection is performed. 
     When the user selects one print mode from the plural digital book print modes, the main control part  70  displays a setting screen of the selected digital book print mode on the display part  79  of the control panel  76  similarly to  FIG. 4  (Act  204 ). Further, on this setting screen, when the user specifies the page range of the digital book data and specifies the size of a sheet to be printed (Act  205 ), the main control part  70  fetches the digital book data within the specified page range from a page memory  75 , and controls a sheet conveyance part  15  so that a sheet of the specified sheet size is taken out from one of cassette mechanisms  30   a  to  30   d . Next, the main control part  70  sets the digital book print mode displayed on the display part  79  of the control panel  76  at Act  204  to the image forming apparatus (Act  206 ), or when the normal print mode is set at Act  202 , the main control part  70  starts printing in accordance with the setting (Act  207 ). 
     Incidentally, in the mode  2  shown in  FIG. 9 , the saddle folding means that in a saddle stitch part  40  of a finisher  12 , a sheet bundle is folded in two without stapling the sheet bundle. 
     Also in the image forming apparatus and the image forming method of this embodiment described above, when the determination is that the image data to be printed is the digital book data, the digital book print mode for forming a book from the digital book data is automatically displayed on the display part  79  of the control panel  76 , and this mode is automatically set to the image forming apparatus  10 . Accordingly, the user can easily print the digital book and forms the book. 
     Further, according to the image forming apparatus and the image forming method of this embodiment, the plural digital book print modes are displayed on the display part  79  of the control panel  76 , and the user can select one mode from these. Accordingly, the user can form a more desirable book. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions. 
     For example, the digital book print mode is not limited to the print mode shown in the embodiment. For example, the user operates the control panel  76  and can appropriately specify the digital book print mode. Accordingly, the digital book print mode may be, for example, only the magazine sort and two-sided printing. 
     The various digital book print modes specified as stated above are stored in the RAM  74  of the main control part  70 . When the determination part  72  determines that the image data is the digital book data, the specified digital book print mode is read from the RAM  74  and is displayed on the display part  79 , and this print mode is set to the image forming apparatus  10 . In this case, the main control part  70  controls at least one of the image processing part  71 , the inversion conveyance part  32  and the finisher control part  78  according to the specified digital book print mode.