JP2004333547A - Color image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to form a color image in an area corresponding to the peripheral length of an intermediate transfer body and to output an image to a long paper, in a color image forming apparatus. <P>SOLUTION: The color image forming apparatus is provided with the intermediate transfer body and has two or more color modes in which the numbers of toner colors to be used are respectively different. When a color mode to which toner color constitution disabling simultaneous image formation on the intermediate transfer body is applied, is selected, a long printing for forming a color image only in an area of the paper which is less than the peripheral length of the intermediate transfer body is performed in accordance with the sub-scanning length of the paper as shown in Fig.(b). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a color image forming apparatus such as a copying machine provided with an intermediate transfer member, and more particularly to a long-size printing thereof.
[0002]
[Prior art]
Conventionally, in a monochrome image forming apparatus, there is an image forming apparatus in which an output function for a long sheet that is long in the sub-scanning direction is mounted (this is generally performed, but no known document is found). )), There is no color image forming apparatus provided with an intermediate transfer member that has an output function for long paper.
[0003]
[Problems to be solved by the invention]
Among color image forming apparatuses, in the case of a color image forming apparatus having a structure in which a developing unit is switched for each color to form an image on an intermediate transfer body in order and an image is transferred from the intermediate transfer body to a sheet, the intermediate transfer body is used. However, there is a problem that an image cannot be formed on a sheet having a size exceeding the circumference.
[0004]
The present invention has been made under such circumstances, and in a color image forming apparatus, it is possible to form a color image on an area corresponding to the peripheral length of an intermediate transfer member, and output the image to a long sheet. It is an object of the present invention to make it possible.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, in the present invention, a color image forming apparatus is configured as in the following (1) and (2).
[0006]
(1) A color image forming apparatus having two or more color modes using different numbers of toner colors,
An intermediate transfer member,
When a color mode in which a toner color configuration that cannot simultaneously form an image is applied to the intermediate transfer body is selected, depending on the sub-scanning length of the paper, a value equal to or less than the circumference of the intermediate transfer body on the paper is used. Control means for enabling image formation only in the area,
A color image forming apparatus comprising:
[0007]
(2) An image forming apparatus having one or more color modes using different numbers of toner colors,
An intermediate transfer member,
Only when the sub-scanning length of the sheet is equal to or less than the peripheral length of the intermediate transfer body, a control unit that enables selection of a color mode in which a toner color configuration capable of simultaneously forming an image on the intermediate transfer body is applied,
A color image forming apparatus.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to examples of a color image forming apparatus. The present invention is not limited to the form of the apparatus, but can be implemented in the form of a method or a program, supported by the description of the embodiment.
[0009]
【Example】
FIG. 1 is a block diagram showing a configuration of a control system in a "color image forming apparatus" (copier) according to an embodiment.
[0010]
In FIG. 1, reference numeral 101 denotes a CPU, a program for performing control by the apparatus of the embodiment (hereinafter also referred to as the apparatus), data displayed on an LCD panel 106, a copy mode program, and key input from a ROM indicated by 102. A detection program, a communication program with an external operation device, and the like are read to control the device.
[0011]
A RAM 103 stores data to be temporarily stored by a program read from the ROM 102 by the CPU 101. The CPU 101 stores and reads data in the RAM 103 as necessary. Reference numeral 104 denotes a backup RAM, which enables information set for operating the apparatus to be recorded even when the apparatus is turned off, and which is powered by a backup battery (not shown). Supplied.
[0012]
Reference numeral 105 denotes an input / output port of the CPU 101, via an apparatus connected to the CPU 101. An LCD panel 106 on the operation panel displays each copy mode, setting procedure, and the like. The LCD panel 106 includes an LCD unit of a touch panel type LCD panel. Reference numeral 107 denotes a key for operating the apparatus. Reference numeral 108 denotes a network communication I / F which connects to a network using a wired or wireless medium and communicates image data and control information with devices on the network based on a specific communication protocol. It is. Reference numeral 109 denotes a sensor, which includes a photodiode, a tact switch, a humidity sensor, and the like, includes an A / D converter depending on the type of the sensor, and monitors various states in the apparatus. A motor driver 110 drives a stepping motor and a DC motor in the apparatus.
[0013]
FIG. 2 is a cross-sectional view illustrating the overall configuration of the color image forming apparatus main body of the present embodiment.
[0014]
In FIG. 2, reference numeral 201 denotes a document reading device. The original reading device 201 has an image sensor such as a CCD and a color separation filter, and performs reciprocal scanning of the image sensor by a motor (not shown) to perform color separation on the entire image of the original placed on the original reader 201. Into electrical signals. The image converted into an electric signal by the document reading device 201 is subjected to necessary image processing by the CPU 101 and then sent to the printer unit 250.
[0015]
Reference numerals 202 to 205 denote toner units, in which toners of different colors such as BK, 203 (C (cyan)), 204 (M (magenta)), and 205 (Y (yellow)) are loaded. Reference numerals 206 to 209 denote developing units, and 206 is a BK developing unit, 207 is a C (cyan) developing unit, 208 is a M (magenta) developing unit, and 209 is a Y (yellow) developing unit. The toner units 202 to 205 are configured to supply toner to the developing units 206 to 209 by screws or the like.
[0016]
Reference numeral 210 denotes a rotary, on which the color toner units 203 to 205 and developing units 207 to 209 excluding BK are mounted. The BK developing device is installed at a position different from the rotary. Reference numeral 211 denotes a photoconductor, on which a toner image is formed by the developing units 206 to 209. By rotating the rotary 210, the developing devices 207 to 209 can be sequentially brought into close contact with the photoconductor 211. Therefore, each color toner unit cannot form an image on the photoconductor 211 at the same time. Therefore, the present apparatus transfers the toner image to the sheet after forming one or more toner images on the intermediate transfer member indicated by 214 via the photoconductor 211.
[0017]
A charger 212 charges the surface of the photoconductor 211. An exposure control unit 213 converts an electric signal into an optical signal, modulates the signal in accordance with an image signal, and irradiates the photoconductor 211 with the light signal. By this irradiation, an electrostatic latent image is generated on the photoconductor 211, and a developing device develops a toner image corresponding to the electrostatic latent image. Reference numeral 214 denotes an intermediate transfer member. The toner image developed on the photosensitive member 211 is first primarily transferred to the intermediate transfer member 214 before being transferred to a sheet. A primary transfer roller 215 is provided in the direction facing the photoconductor 211 to stably transfer the toner image to the intermediate transfer body 214. The residual toner not transferred from the photoconductor 211 to the intermediate transfer body 214 is removed by the cleaner 216. The toner image on the intermediate transfer member 214 is transported to the secondary transfer roller 217 and is transferred to a sheet.
[0018]
The secondary transfer roller 217 can be joined to or separated from the intermediate transfer member 214 by a secondary transfer roller attaching / detaching motor 218. Further, a registration roller 219 is provided to convey the sheet to the secondary transfer roller 217 at an appropriate timing. The registration roller 219 is for temporarily stopping the sheet conveyed up to immediately before, and advancing the sheet conveyance in accordance with the image forming timing, thereby transferring the toner image to an appropriate position on the sheet.
[0019]
The residual toner remaining on the intermediate transfer body 214 without being completely transferred onto the paper is collected by the intermediate transfer body cleaner 220.
[0020]
In the case of this embodiment, since there is only one exposure control unit, BK, Y, M, and C toner images cannot be formed simultaneously. Therefore, in the case of a color mode using a plurality of toner colors such as a full-color mode, the rotary 210 is rotated every time a toner image of one color is formed, and a toner image is sequentially formed on the photoconductor 211, and the intermediate transfer is performed. It is necessary to superimpose a plurality of color toner images on the body 214 and then secondary-transfer them onto paper. For this reason, in the color mode using a plurality of toner colors, image formation on paper having a sub-scanning length exceeding the circumference of the intermediate transfer member 214 is limited. On the other hand, there is no limitation in a color mode using only one toner color, such as a monochrome mode or a single color mode.
[0021]
In this embodiment, only one exposure control unit 213 is provided, but two exposure control units may be provided for color toner development and BK toner development. In this case, since it is possible to simultaneously form the toner image of the BK toner and the color toner, the color mode in which the image is formed by two colors of the BK toner and one color toner is also used in the monochrome mode or the single color mode. As described above, there is no limitation on the image forming area to the sub-scanning length of the sheet.
[0022]
As described above, in the case of a color image forming apparatus that performs image formation by switching developing units located at different positions depending on the color mode, the image formable area depends on the circumference of the intermediate transfer body and the used toner color configuration. . FIG. 3 shows an example of an output result on paper by such a color image forming apparatus. That is, in the case of the color mode in which one toner color or a combination of toner colors capable of simultaneously forming an image is used, as shown in FIG. In the case of the color mode in which an image can be formed in the area but the combination of toner colors that requires switching of the developing device, as shown in FIG. An image is formed. At this time, if the sub-scanning length of the sheet is larger than the peripheral length of the intermediate transfer member, a margin is formed at the front end, the rear end, or both. At this time, by making the front end margin equal to the rear end margin, the image forming position can be set at the center of the sheet.
[0023]
Paper 221 used for image formation by this apparatus is stored in a paper cassette 222, taken out by a paper feed roller 223, and fed. Also, it is possible to feed paper of any size by the manual feed tray 224. The fed paper 221 is temporarily stopped by the registration rollers 219 until the toner image is completely formed on the intermediate transfer body 214. When the toner image is formed on the intermediate transfer member 214, the toner image is conveyed to the secondary transfer roller 217 by the registration roller 219. At this time, the secondary transfer roller 217 is in a rotating state in contact with the intermediate transfer member 214 by the secondary transfer roller attaching / detaching motor 218, and the toner image is transferred from the intermediate transfer member 214 to the sheet on the secondary transfer roller 217. . The sheet on which the toner image has been transferred is conveyed to fixing units 225 and 226 and is heated and pressed, so that a fixed image based on the toner image is formed on the sheet.
[0024]
The sheet on which the fixed image is formed is conveyed to the sheet discharge unit 227, the sheet discharge tray 228, or the reversing path 229 during one-sided printing. Which of the sheet discharging unit 227, the sheet discharging tray 228, and the reversing path 229 the sheet is conveyed is determined by the directions of the flappers 230 and 231 driven by a solenoid (not shown). At the time of double-sided printing, the sheet on which image formation on both sides has been completed is conveyed to the paper discharge unit 227 or the paper discharge tray 228. The sheet is conveyed to the double-sided standby path 233 by the flapper 232. The sheet waiting in the double-sided standby path 233 is again conveyed to the secondary transfer roller 217 via the registration roller 219 at an appropriate timing, and the image on the back surface is formed.
[0025]
FIG. 4A shows the completion timing of the image formation on the intermediate transfer member 214, the drive timing of the registration roller 219, and the drive timing of the secondary transfer roller detachment motor 218 described above. That is, the driving of the registration roller 219 is started in response to the completion of the image formation on the intermediate transfer body 214, and the conveyance of the sheet to the secondary transfer roller 217 is started. Also, after an appropriate margin time at the front end of the paper and the paper transport time, the drive of the secondary transfer roller attaching / detaching motor 218 is started, and the intermediate transfer member 214 is sandwiched between the secondary transfer rollers 217 by sandwiching the paper. In close contact. By the above operation, the toner images are transferred onto the paper at one time in a state where the toner images of a plurality of colors are formed on the intermediate transfer body 214 in a superimposed manner.
[0026]
Reference numeral 401 shown in FIG. 5 is an operation panel of the present apparatus. Reference numeral 402 denotes a touch panel type LCD panel on the operation panel 401, which has a function of displaying an operation state of the apparatus, an operation designation performed by a user, a setting of the apparatus, and an operation input function of the user. .
[0027]
A start button 403 is a button for starting the operation of the apparatus based on the operation designation performed by the user. A stop button 404 is a button for stopping an operating device.
[0028]
Numeral 405 is a button for designating the number of copies and inputting various set values. A reset button 406 is a key for returning copy settings to initial values. A guide button 407 is a button for displaying a description in the current state on the touch panel LCD panel 402.
[0029]
A user mode button 408 is a button for shifting to a user mode for performing settings suitable for the user.
[0030]
A standby mode button 409 is used to shift to a mode for reducing power consumption when the apparatus is not used for a while or to return to the normal mode.
[0031]
Reference numeral 501 shown in FIG. 6 is a screen normally displayed on the touch panel type LCD panel 402. The display unit 502 is a message that displays the current state. Reference numeral 503 denotes a color designation, which can be selected from color / monochrome automatic selection, color, and monochrome. Reference numeral 504 denotes an input unit for enlarging / reducing an original, which can enlarge or reduce the original. Reference numeral 505 denotes double-sided designation for designating double-sided printing of a document. Reference numeral 506 denotes a sheet size designation for changing the size of the sheet to be output.
[0032]
Reference numerals 507, 508, and 509 are used to set output densities. When the light button 507 is touched, the level is reduced by one step, when the dark button 509 is touched, the level is increased by one step. The density is determined and the output density is controlled. Reference numerals 510, 511, and 512 are used to change the image mode. Touching 510 displays a character mode for a high-contrast text document, and touching 512 displays a photo mode for a photographic document with many intermediate gradations. Touching 511. Then, the mode is set to the character / photograph mode when the text document and the photo document are mixed. Reference numeral 513 denotes a mode for shifting to the application mode, in which print settings such as binding margin, bookbinding, OHP insertion, and long paper can be performed.
[0033]
When the application mode button 513 is pressed, the screen shifts to an application mode setting screen shown in FIG. A screen 601 is displayed on the touch panel LCD panel 402 in the user mode. A page continuous shooting button 602 is used to copy a double-page spread. A cover / insert button 603 is used to feed only the first sheet and the last sheet from different sheet feed trays. A reduced layout button 604 is used to reduce a document and copy the document to a predetermined position on output paper. A bookbinding button 605 is used to copy a document with a blank space in the binding direction. Reference numeral 606 denotes an OHP insertion button for alternately outputting OHP and plain paper. Reference numeral 607 denotes a binding margin setting button for designating printing by shifting the image by a designated value. An image quality adjustment button 608 is used to adjust the image quality. Reference numeral 609 denotes a negative / positive reversing button for performing a negative / positive reversal of the color of a document to perform copying. Reference numeral 610 denotes a mirror image button for making a copy by inverting the original horizontally. A long button 611 is used to copy a long sheet that is long in the sub-scanning direction.
[0034]
The cancel button 612 is a button for returning to the normal screen 501 (FIG. 6) without actually reflecting the settings made after shifting to the application mode screen 601. The OK button 613 is a button for actually reflecting the settings made on the application mode screen 601 and returning to the normal screen 501.
[0035]
When the long button 611 is touched, the long paper mode is turned on, and the color of the button 611 is inverted. At this time, if “color / monochrome automatic selection” is designated in the color designation 503 in FIG. 6, the color designation is changed to “black and white”. If the color designation is set to “color”, a warning screen as shown in a window 621 in FIG. 7B is displayed, and the user touches the confirmation button 622, and then the color designation 503 is displayed. Change to “black and white”. With the above operation, printing on long paper can be realized only in the black and white mode.
[0036]
It is to be noted that the OK button 613 is touched on the screen of FIG. 7B or the confirmation button 622 is touched on the screen of FIG. 7B to return to the display screen of FIG. Returning to step 501, if the color designation 503 is changed to "color" again, it is assumed that color output has been intentionally designated, and full-color output to long paper is performed. However, in the case of full color, there is a limitation on the sub-scanning length described above. Therefore, if the color designation is changed with the button 503 after the designation of the long document 611 on the application mode screen 601, the irregular paper size designation screen 801 shown in FIG. To indicate that the size of the long paper is input in advance.
[0037]
The irregular paper size designation screen 801 can also be called from the paper size selection screen 701 shown in FIG. 8, which is displayed when the user touches the paper selection 506 in FIG.
[0038]
A paper size selection screen 701 includes A4 paper size designation 702, A6R paper size designation 703, A4R paper size designation 704, B4 paper size designation 705, A3 paper size designation 706, B5 paper designation 707, A5R paper size designation 708, B5R paper It comprises a paper size selection button such as a size specification 709, an A5 paper size specification 710, an irregular paper size specification 711, etc., a cancel button 712 and an OK button 713. When one of the paper size selection buttons 702 to 710 is touched, the standard paper size displayed on the button can be registered as an output paper size. When the user touches the irregular paper size button 712, the screen shifts to an irregular paper size designation screen 801. The cancel button 712 is for returning to the normal screen 501 without actually reflecting the result of the paper size selection. The OK button 713 is for actually reflecting the paper size selection result and displaying the specified paper size on the display unit 502 of the normal screen 501.
[0039]
When the irregular paper size specification screen 801 is called from the paper size specification screen 701, if the sub-scanning length is set longer than the standard paper size, the paper size in the full color mode is set in the same manner as when the long mode is set. Is limited to the circumference of the intermediate transfer member, and an appropriate margin is set on the irregular-size paper size designation screen 801.
[0040]
On the irregular paper size designation screen 801, the length, width, and size of the margin can be designated. When the user touches the X direction designation portion 802, the length of the sheet can be input from the ten keys 405. The input sheet length in the X direction is displayed on the X direction display unit 804. When the user touches the Y direction designation portion 803, the width of the sheet can be input from the ten keys 405. The input paper width in the Y direction is displayed on the Y axis direction display unit 805.
[0041]
Here, if the user touches a margin designation portion 807, the user can input a margin at the front end of the sheet from the ten keys 405. The input value is displayed on the front margin display section 806. When the user touches the center margin button 808, the margin size is automatically determined based on the designated paper size and the original size, the front margin and the rear margin are made equal, and an image is formed at the center of the paper. When outputting to long paper in the full-color mode, if the sub-scanning length of the document is longer than the circumference of the intermediate transfer body, the output is performed only for the circumference of the intermediate transfer body. Reference numeral 809 denotes a cancel button for returning to the screen of the caller without reflecting the settings made on the irregular-size paper size designation screen 801 in the actual operation. An OK button 810 is used to reflect the settings made in the irregular-size paper size designation screen 801 on the actual operation and return to the caller screen. When the centering button 808 is enabled in the full-color mode, the result of image formation on the paper is that the sub-scanning length of the toner image on the paper is equal to or less than the circumference of the intermediate transfer member, as shown in FIG. , And the leading and trailing margins are equal.
[0042]
If the front end margin in the sub-scanning direction is specified on the irregular-size paper size designation screen 801, the secondary transfer roller 217 is moved to the intermediate position by the secondary transfer roller attaching / detaching motor 218 after the front end of the paper has passed the registration roller 219 during paper conveyance. By setting the time until the transfer member 214 is in close contact with the transfer body 214 longer than usual, the front margin of the sheet is adjusted. In addition, when the front margin is set to 0 without particularly setting the full-color mode even though the full-color mode is designated, image formation is performed only for the circumference of the intermediate transfer member from the front end of the sheet.
[0043]
FIG. 4B shows the timing of completing the image formation on the intermediate transfer member 214, the driving timing of the registration roller 219, and the driving timing of the secondary transfer roller attaching / detaching motor 218 described above. That is, before the image formation is completed, the driving of the registration roller 219 is started based on the image formation required time and the sheet conveyance time, and the front end of the sheet passes through the secondary transfer roller 217. At the timing when the front end of the sheet has passed the secondary transfer roller 217 by the designated front end margin, the image formation is completed, and the secondary transfer roller detaching motor 218 is driven to interpose the sheet between the secondary transfer rollers 217. The transfer member 214 is brought into close contact with the transfer member 214. With the above operation, in a state where the toner images of a plurality of colors are formed on the intermediate transfer body 214 in an overlapping manner, the toner images can be transferred at a time from a position shifted by an arbitrary margin from the front end of the sheet to form an image. is there.
[0044]
FIG. 10 shows the screen transition on the operation panel.
[0045]
With the above operations and controls, even in the full color mode, long printing can be performed only in the area less than the circumference of the intermediate transfer body regardless of the paper size and the original size. It is possible to output an image to a specified position.
[0046]
The present device includes a device having a function of communicating image data and control information with devices on the network via a network using a wired or wireless medium. As an example of an electronic information device connected to the network, there is an electronic computer (hereinafter, referred to as a computer) capable of transmitting image data to this apparatus and outputting an image. An operation and an operation of the apparatus when image data and control information are transmitted from the computer to the apparatus to form an image will be described.
[0047]
A computer connected to the apparatus via the network converts image data in the computer into a form suitable for the apparatus and transmits and prints the image data. A printer driver is used as software for specifying printing.
[0048]
Reference numeral 1001 in FIG. 11 denotes a detailed setting screen when the print image data is transmitted to the apparatus in the printer driver software. Reference numeral 1002 denotes a paper feed cassette selection unit that stores paper to be subjected to image formation in this apparatus. Reference numeral 1003 denotes a sheet direction designation unit for forming an image with the apparatus. Reference numeral 1004 denotes a designation unit for determining whether or not to perform double-sided printing when forming an image with the present apparatus. Reference numeral 1005 denotes a resolution when image formation is performed by the present apparatus, and can be selected from 300 dpi, 600 dpi, and 1200 dpi. A color designation button 1006 can be selected from color / black and white (automatic selection), color, and black and white. A manual paper size designation button 1007 is a button for shifting to a paper size designation screen. The manual feed paper size designation 1007 is enabled only when “manual feed tray” is selected in the paper feed cassette selection unit 1002, and when any other value is selected, it is grayed out and cannot be pressed. Reference numeral 1011 denotes a decision button, which is a button for applying the settings on the printer driver detailed setting screen 1001 and closing the screen. A cancel button 1012 is used to discard settings on the printer driver detailed setting screen 1001 and close the screen.
[0049]
When the manual paper size designation button 1007 is pressed, the screen shifts to a manual paper size designation screen 1101 shown in FIG. Reference numeral 1102 denotes a paper insertion direction display unit, which indicates to a user of this apparatus the direction at the time of paper insertion. Reference numeral 1103 denotes a standard paper size specification unit for specifying a standard paper size when using standard paper. Reference numerals 1104 and 1105 denote length designation units in the X and Y directions, respectively, which allow designation of the sub-scanning length and the main scanning length of the paper in units of mm, and the standard paper size designated by the standard paper size designation unit 1103. Can be displayed. Reference numeral 1106 denotes a margin designation unit which enables designation of a front end margin of a sheet separately from a margin designated by application software. Reference numeral 1107 denotes a center designation check box. When this checkbox is activated, the front margin is automatically adjusted based on the designated dimensions of the print data and the designated paper size, and the front margin and the rear margin are made equal to output an image at the center of the paper. It is to make it. An enter button 1108 is used to apply each of the above designations. A cancel button 1109 is used to return to the original screen without applying each of the above-mentioned designations.
[0050]
When the front end margin is designated by the above operation, and in the actual operation, when the paper size is larger than the circumference of the intermediate transfer body in the full color mode, the intermediate transfer is performed after the paper front end passes through the registration roller 219 during the paper conveyance. The front end margin of the paper is designated by making the time until the image formation is completed on the body 214 and the secondary transfer roller 217 is brought into close contact with the intermediate transfer body 214 by the secondary transfer roller attaching / detaching motor 218 longer than usual. Value. In addition, when the front margin is set to 0 without particularly setting the full-color mode even though the full-color mode is designated, image formation is performed only for the circumference of the intermediate transfer member from the front end of the sheet.
[0051]
As described above, according to the present embodiment, even in the full-color mode, long printing can be performed only in an area smaller than the peripheral length of the intermediate transfer body regardless of the size of the paper or the original, and the original can be printed on the intermediate transfer body. If the length is less than the circumference, it is possible to output an image to an intended position.
[0052]
That is, in a color image forming apparatus including an intermediate transfer member and a color mode having a toner color configuration that cannot form an image at the same time, when the color mode is selected, a color corresponding to the peripheral length of the intermediate transfer member is It is possible to form an image and output to long paper.
[0053]
Also, in the color mode using the single-color toner, images can be output to the entire length of the long paper without limitation.However, when the long paper is selected, the full color mode cannot be selected. The present invention provides a color image forming apparatus capable of forming an image in an area corresponding to the circumference of the intermediate transfer member of the color image forming apparatus by changing the image forming start position of the color image forming apparatus and maximizing the functions of the apparatus. It becomes possible.
[0054]
Here, the embodiments supported by the description of the above-described embodiment will be listed below.
[0055]
(1) A color image forming apparatus having two or more color modes using different numbers of toner colors,
An intermediate transfer member,
When a color mode in which a toner color configuration that cannot simultaneously form an image is applied to the intermediate transfer body is selected, depending on the sub-scanning length of the paper, a value equal to or less than the circumference of the intermediate transfer body on the paper is used. Control means for enabling image formation only in the area,
A color image forming apparatus comprising:
[0056]
(2) In the color image forming apparatus according to (1),
When the peripheral length of the intermediate transfer body is smaller than the sub-scanning length of the specified paper size, the control unit changes the paper conveyance timing according to the image size, thereby setting the front end margin of the paper to an arbitrary length. A color image forming apparatus wherein the image forming start position is shifted.
[0057]
(3) In the color image forming apparatus according to (1),
When the peripheral length of the intermediate transfer member is less than the sub-scanning length of the specified paper size, the control unit changes the paper conveyance timing according to the image size so that the front margin and the rear margin of the paper are equal. The image forming apparatus is characterized in that the image forming start position is shifted.
[0058]
(4) A color image forming apparatus having two or more color modes using different numbers of toner colors,
An intermediate transfer member,
When the sub-scanning length of the sheet exceeds the peripheral length of the intermediate transfer body, a control unit that allows selection of only a color mode in which a toner color configuration capable of simultaneously forming an image on the intermediate transfer body is applied,
A color image forming apparatus comprising:
[0059]
(5) In the color image forming apparatus according to (4),
A color image forming apparatus including a monochrome mode as a color mode in which a toner color configuration capable of simultaneously forming an image on the intermediate transfer body is applied.
[0060]
(6) In the color image forming apparatus according to (4),
A color mode that uses black and one color toner other than black as a color mode in which a toner color configuration capable of simultaneously forming an image on the intermediate transfer body is applied.
(7) In the color image forming apparatus according to (4),
A color image forming apparatus including a single color mode as a color mode in which a toner color configuration capable of simultaneously forming an image on the intermediate transfer body is applied.
[0061]
(8) In the color image forming apparatus according to (7),
A color image forming apparatus comprising, as a single color mode, a color mode using only one color of toner.
[0062]
(9) An image forming method in a color image forming apparatus including an intermediate transfer body,
Step A of selecting one of color / black and white automatic selection, color and black and white color designation,
Step B for specifying long-size printing;
When the color / monochrome automatic selection or the color is selected in the step A, when the long printing is designated in the step B, the printing is changed to the black and white printing and the long printing is performed;
An image forming method comprising:
[0063]
(10) In the image forming method according to the above (9),
Step D of selecting a color again from color / black and white automatic selection, color and black and white color designation,
When the color is selected again in the step D, a step E of performing a long printing for forming a color image only on an area not more than the circumference of the intermediate transfer body on a sheet;
An image forming method comprising:
[0064]
(11) An image forming method in a color image forming apparatus including an intermediate transfer member and having two or more color modes using different numbers of toner colors,
Selecting a color mode in which a toner color configuration that cannot simultaneously form an image is applied to the intermediate transfer body;
When the color mode in which the toner color configuration that cannot simultaneously form an image is applied is selected in the step F, only an area equal to or less than the peripheral length of the intermediate transfer body on the paper is selected according to the sub-scanning length of the paper. A step G of performing long printing for forming a color image on
An image forming method comprising:
[0065]
(12) An image forming method in a color image forming apparatus including an intermediate transfer member and having two or more color modes using different numbers of toner colors,
When the sub-scanning length of the sheet exceeds the peripheral length of the intermediate transfer body, a step H of selecting only a color mode in which a toner color configuration capable of simultaneously forming an image on the intermediate transfer body is applied;
A step I of performing long printing exceeding the circumference of the intermediate transfer body when a color mode in which a toner color configuration capable of simultaneously forming an image is applied is selected in the step H;
An image forming method comprising:
[0066]
(13) A program for implementing the image forming method according to any one of (9) to (12).
[0067]
【The invention's effect】
As described above, according to the present invention, in a color image forming apparatus including an intermediate transfer member and a color mode having a toner color configuration that cannot simultaneously form an image, when the color mode is selected, the intermediate transfer member is A color image can be formed in an area corresponding to the perimeter, and output to long paper is possible.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a control system in an embodiment.
FIG. 2 is a cross-sectional view showing the overall configuration of the embodiment.
FIG. 3 illustrates an example of an image forming position on a sheet.
FIG. 4 is a timing chart showing the operation of the embodiment.
FIG. 5 is a diagram showing an operation panel.
FIG. 6 is a diagram showing an example of a display screen of an LCD panel.
FIG. 7 is a diagram showing a display screen regarding an application mode.
FIG. 8 is a diagram showing a display screen for paper selection.
FIG. 9 is a diagram showing a screen for specifying a non-standard paper size.
FIG. 10 is a diagram showing a screen transition.
FIG. 11 is a diagram showing a detailed setting screen when transmitting a print image in the computer.
FIG. 12 is a diagram showing a manual paper size designation screen on a computer.
[Explanation of symbols]
101 CPU
106 LCD panel
214 Intermediate transfer member

Claims (2)

A color image forming apparatus having two or more color modes using different numbers of toner colors,
An intermediate transfer member,
When a color mode in which a toner color configuration that cannot simultaneously form an image is applied to the intermediate transfer body is selected, depending on the sub-scanning length of the paper, a value equal to or less than the circumference of the intermediate transfer body on the paper is used. Control means for enabling image formation only in the area,
A color image forming apparatus comprising: An image forming apparatus having one or more color modes that use different numbers of toner colors,
An intermediate transfer member,
When the sub-scanning length of the sheet exceeds the peripheral length of the intermediate transfer body, a control unit that allows selection of only a color mode in which a toner color configuration capable of simultaneously forming an image on the intermediate transfer body is applied,
An image forming apparatus comprising:

Images