JP5755077B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus to which a process cartridge can be attached and detached. The electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming process. Examples of the electrophotographic image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (laser beam printer, LED (light emitting diode) printer, etc.), and the like.

  The recording medium is an image on which an image is formed using an electrophotographic image forming process. For example, a recording sheet, an OHP (Overhead projector) sheet, a label, and the like.

  Further, the process cartridge is an electrophotographic image forming apparatus in which an electrophotographic photosensitive member and at least one of a processing unit acting on the electrophotographic photosensitive member, for example, a developing unit, a charging unit, and a cleaning unit are integrally formed into a cartridge. It can be attached to and detached from the main body.

  Here, the process cartridge can be attached to and detached from the apparatus main body by the user himself, and the operability of the apparatus is very excellent.

  Conventionally, in a color electrophotographic image forming apparatus, a configuration in which a plurality of process cartridges are supported by a movable member that is movable with respect to the apparatus main body has been considered. According to this configuration, a plurality of process cartridges can be simultaneously inserted into the apparatus main body.

  Hereinafter, a conventional color electrophotographic image forming apparatus will be described with reference to FIGS.

  FIG. 6 shows a cross section of a conventional color electrophotographic image forming apparatus. The photosensitive drums 1K, 1C, 1M, and 1Y are detachably attached to the image forming apparatus main body as process cartridges 9K, 9C, 9M, and 9Y integrated with the developing rollers 5K, 5C, 5M, and 5Y. Yes.

  Hereinafter, in order to prevent the description from becoming complicated, the process cartridges 9K, 9C, 9M, and 9Y of K (black), C (cyan), M (magenta), and Y (yellow) are represented by the process cartridge 9. To do. The same applies to each related process means.

  A moving member that moves while holding the process cartridge 9 is referred to as a cartridge tray 26.

  The cartridge tray 26 is supported by a guide rail 27 with respect to the image forming apparatus main body, and is slidable in the left-right direction in FIG.

  FIG. 7 shows a state in which the cartridge tray 26 is pulled out from the image forming apparatus main body with the door 28 opened. In this state, the upper surface of each process cartridge 9 is opened, and each process cartridge 9 can be removed upward as shown in FIG.

  A color image forming apparatus having such a configuration is disclosed in Patent Document 1.

  In such a color image forming apparatus, output of a color image (full color mode) is not always required, and output of a monochrome image such as black only (monochrome mode) is often required.

  In order to meet this requirement, in Patent Documents 2 and 3, when the full color mode is selected, all the photosensitive drums 1 are brought into contact with the transfer material. There has been proposed a color image forming apparatus having a configuration in which only the black photosensitive drum 1K is brought into contact with a transfer material when the monochrome mode is selected.

JP 2007-213081 A (FIGS. 1 to 6) Japanese Patent Laying-Open No. 2005-338437 (FIG. 6) JP 2001-318508 A (FIGS. 1 and 2)

  The conventional color electrophotographic image forming apparatus described above needs to move the process cartridge 9 away from the intermediate transfer belt 18 in order to move the cartridge tray 26 in order to perform operations such as replacement of the process cartridge 9.

  In addition, a separation mechanism for switching between the full color mode and the monochrome mode is provided in order to prevent damage to the intermediate transfer belt 18 and the photosensitive drum 1 in the monochrome mode and to suppress toner deterioration due to roller rotation or the like in the process cartridge 9. Then, it becomes a complicated structure by combining with the separation mechanism that accompanies work such as replacement of the process cartridge 9, and the apparatus tends to increase in size.

  In the present invention, the mechanism for separating the plurality of process cartridges from the image bearing belt in association with the work such as process cartridge replacement is the same as the switching mechanism between the full color mode and the monochrome mode. Thereby, a mechanism can be simplified. Further, since the process cartridge is separated from the image bearing belt, a space for retracting the process cartridge is not required. Accordingly, it is possible to reduce the size of the apparatus and to realize a contact / separation mechanism between the process cartridge and the image carrying belt at low cost.

  A typical configuration of the image forming apparatus according to the present invention for achieving the above object is to develop an image carrier on which an electrostatic latent image is formed, and develop the electrostatic latent image formed on the image carrier. A process cartridge having an image forming process means for forming a toner image, an image carrier belt disposed opposite to the image carrier, and disposed on the opposite side of the image carrier across the image carrier belt The transfer means for transferring the toner image formed on the image carrier to the image carrier belt and a plurality of the process cartridges are detachably mounted and linearly along the conveying direction of the image carrier belt. And a transfer means for exposing the process cartridge to the outside from an opening provided in the main body of the image forming apparatus, and the transfer means for all colors in contact with the image carrier with the image carrier belt in between Let me A mode switching unit that switches between a color mode and a monochrome mode in which only the single color transfer unit is brought into contact with the image carrier with the image carrier belt interposed therebetween, and is used for image formation in the monochrome mode; The single-color process cartridge is disposed farthest from the opening of the image forming apparatus main body with respect to the moving direction of the moving means, and is furthest from the opening of the image forming apparatus main body in the monochrome mode. The moving means is movably provided in a state where only the monochromatic transfer means is in contact with the image carrier of the monochromatic process cartridge disposed on the image carrier belt. .

  According to the above configuration, the single-color process cartridge used for image formation in the monochrome mode is disposed farthest from the opening of the image forming apparatus main body with respect to the moving direction of the moving unit. In the monochrome mode, the moving means is in a state in which only the monochrome transfer means is in contact with the image carrier of the monochrome process cartridge disposed farthest from the opening of the main body of the image forming apparatus. It is provided so as to be movable. As a result, the mode is switched to the monochrome mode, and the moving means in which the process cartridge is detachably mounted is linearly moved along the conveying direction of the image carrier belt to remove the process cartridge from the opening provided in the image forming apparatus main body. Can be exposed outside.

  As described above, according to the present invention, the contact / separation mechanism capable of switching between the monochrome mode and the full color mode is provided. As a result, it is possible to prevent damage to the image carrier belt and the image carrier in the monochrome mode, and to suppress toner deterioration due to roller rotation in the process cartridge.

  Further, the moving means for supporting the process cartridge can be pulled out from the apparatus main body with a small contact area between the process cartridge and the image carrier belt in the monochrome mode. Thereby, it is not necessary to newly provide a contact / separation mechanism for pulling out the moving means. Further, since the process cartridge is separated from the image bearing belt, a space for retracting all the process cartridges as in the conventional example is not necessary, and a small and inexpensive apparatus can be provided.

FIG. 3 is a cross-sectional explanatory diagram illustrating a state of a full color mode in the first embodiment of the image forming apparatus according to the invention. 1 is a cross-sectional explanatory view showing a state of a monochrome mode in a first embodiment of an image forming apparatus according to the present invention. FIG. 3 is an explanatory cross-sectional view illustrating a state in which a door for taking out a process cartridge is opened in the monochrome mode in the first embodiment of the image forming apparatus according to the invention. FIG. 3 is an explanatory cross-sectional view showing a state in which the process cartridge is taken out by opening a door for taking out the process cartridge in the monochrome mode in the first embodiment of the image forming apparatus according to the present invention. FIG. 10 is an explanatory cross-sectional view showing a state in which a door for taking out a process cartridge is opened in a monochrome mode in the second embodiment of the image forming apparatus according to the present invention. It is a figure explaining the structure of the conventional image forming apparatus. It is a figure explaining the structure of the conventional image forming apparatus.

  An embodiment of an image forming apparatus according to the present invention will be specifically described with reference to the drawings.

  First, the configuration of the first embodiment of the image forming apparatus according to the present invention will be described with reference to FIGS. The image forming apparatus shown in FIGS. 1 to 4 shows an example of a laser beam printer.

<Image forming apparatus>
1 to 4, an intermediate transfer belt 18 serving as an image bearing belt is disposed opposite to the photosensitive drums 1K, 1C, 1M, and 1Y serving as an image bearing member on which an electrostatic latent image is formed. The photosensitive drums 1K, 1C, 1M, and 1Y are detachably attached to the image forming apparatus main body as process cartridges 9K, 9C, 9M, and 9Y integrated with the developing rollers 5K, 5C, 5M, and 5Y. Yes. The process cartridges 9K, 9C, 9M, and 9Y are various image forming process units that develop toner images by developing the electrostatic latent images formed on the photosensitive drums 1K, 1C, 1M, and 1Y (on the image carrier). Have

  Although not shown, the various image forming process means include a charging roller that is disposed on the outer periphery of the photosensitive drums 1K to 1Y and serves as charging means for uniformly charging the surfaces of the photosensitive drums 1K to 1Y. Further, the surface of the photosensitive drums 1K to 1Y whose surfaces are uniformly charged by the charging roller is exposed according to image information to form a laser scanner 25 as exposure means for forming an electrostatic latent image.

  Hereinafter, in order to prevent the description from becoming complicated, four process cartridges 9K, 9C, 9M, and 9Y of black (Bk), cyan (C), magenta (M), and yellow (Y) are represented by the process cartridge 9. To do. The same applies to the related image forming process means.

  Primary transfer rollers 31K, 31C, 31M, and 31Y as transfer means are disposed on the opposite side of the intermediate transfer belt 18 from the photosensitive drum 1. The primary transfer roller 31 transfers the toner image formed on the photosensitive drum 1 to the intermediate transfer belt 18.

  These primary transfer rollers 31 are in contact with the photosensitive drum 1 with the intermediate transfer belt 18 interposed therebetween, and the toner image formed on the photosensitive drum 1 is transferred to the intermediate transfer belt 18.

  In the case of forming a color image, toner images of the respective colors of black (Bk), cyan (C), magenta (M), and yellow (Y) are developed on the photosensitive drums 1K, 1C, 1M, and 1Y. The toner image is transferred while being superimposed on the intermediate transfer belt 18.

  On the other hand, the transfer material 14 such as sheets stacked on the sheet feeding tray 13 is separated and fed one by one by a separation feeding roller 15. Then, it is sent to the nip portion between the drive roller 16 and the transfer roller 17 in synchronization with the toner image formed on the intermediate transfer belt 18 by the registration roller 6.

  Then, the toner image formed on the intermediate transfer belt 18 is transferred to the transfer material 14 by the action of the transfer roller 17. Then, the toner image is heated and pressed by the fixing roller 20 and the pressure roller 21 to be melted and fixed on the transfer material 14, and then is nipped and conveyed by the discharge roller 22 and the discharge roller 23 and discharged onto the discharge tray 24. The

  The photosensitive drum 1 is detachably attached to the image forming apparatus main body as a process cartridge 9 integrated with the developing roller 5 and the like. The cartridge tray 26 is configured as a moving means for detachably mounting a plurality of process cartridges 9.

  The image forming apparatus main body is provided with guide rails 27 arranged in the left-right direction in FIG. The cartridge tray 26 is guided while being held by the guide rail 27 and moves linearly along the conveyance direction of the intermediate transfer belt 18 (the left-right direction in FIG. 4). The process cartridge 9 can be exposed to the outside from the opening 2 provided in the main body of the image forming apparatus.

  A door 28 that can open and close the opening 2 of the image forming apparatus main body is provided to be rotatable with respect to the image forming apparatus main body.

<Switching between full color mode and monochrome mode>
With reference to FIGS. 1 and 2, the configuration and functions around the primary transfer roller 31 in the present embodiment will be described. The image forming apparatus according to this embodiment forms a color image using all the photosensitive drums 1K, 1C, 1M, and 1Y. In addition, a full color mode in which the primary transfer rollers 31K, 31C, 31M, and 31Y of all colors are in contact with the photosensitive drums 1K, 1C, 1M, and 1Y with the intermediate transfer belt 18 interposed therebetween is provided.

  Furthermore, a monochrome image is formed using only the monochrome (black) photosensitive drum 1K. In addition, there is a monochrome mode in which only the single-color primary transfer roller 31K is brought into contact with the photosensitive drum 1K with the intermediate transfer belt 18 interposed therebetween. And it has the cam mechanism controlled by the control part used as the control means which is not shown in figure which becomes a mode switching means which switches a full color mode and a monochrome mode. As an example of the cam mechanism serving as the mode switching means, a separation cam 38 or the like configured as a door interlocking mechanism shown in FIG.

  The cam mechanism is switched to the monochrome mode when the power of the image forming apparatus main body is turned on, when the image forming operation is finished, or when the power is turned off. In the monochrome mode, only the monochromatic primary transfer roller 31K has the intermediate transfer belt 18 sandwiched between the photosensitive drum 1K of the monochromatic process cartridge 9K arranged on the innermost side (left side in FIG. 2) from the opening 2 of the image forming apparatus main body. Are in contact with each other.

  A single-color process cartridge 9K used for image formation in the monochrome mode is disposed farthest from the opening 2 of the image forming apparatus main body with respect to the moving direction of the cartridge tray 26 (left side in FIG. 2).

  In the monochrome mode, a monochrome primary transfer roller with the intermediate transfer belt 18 sandwiched between the photosensitive drum 1K of the monochrome process cartridge 9K disposed on the farthest side (left side in FIG. 3) from the opening 2 of the image forming apparatus main body. Only 31K contacts. In this state, the cartridge tray 26 is movably provided.

  The intermediate transfer belt 18 is rotatably stretched by a first belt unit 35 that is a first support portion and a second belt unit 36 that is a second support portion. The second belt unit 36 is provided so as to be rotatable with respect to the first belt unit 35 around the connection fulcrum 37. The first belt unit 35 is a primary transfer roller 31K provided to face the photosensitive drum 1K of the monochrome process cartridge 9K disposed on the innermost side (left side in FIG. 3) from the opening 2 of the image forming apparatus main body. Is supported rotatably. Further, the first belt unit 35 is provided with a driving roller 16 that rotationally drives the intermediate transfer belt 18 and a driven roller 3 that stretches the intermediate transfer belt 18.

  The second belt unit 36 rotatably supports the primary transfer rollers 31C, 31M, and 31Y. The primary transfer rollers 31C, 31M, and 31Y are the photosensitive drums 1C, 1M, and 1Y of the process cartridges 9C, 9M, and 9Y disposed on the opening 2 side (opening side) of the image forming apparatus main body other than the process cartridge 9K. Are provided opposite to each other. Further, the second belt unit 36 is provided with a tension roller 19 that stretches the intermediate transfer belt 18.

  Then, the monochrome primary transfer roller with the intermediate transfer belt 18 sandwiched between the photosensitive drum 1K of the monochrome process cartridge 9K disposed on the farthest side (left side in FIG. 3) from the opening 2 of the image forming apparatus main body in the monochrome mode. Only 31K contacts. In this state, the second belt unit 36 is rotated with respect to the first belt unit 35 around the connection fulcrum 37.

  The cartridge tray 26 is movably provided with the primary transfer rollers 31C, 31M, 31Y separated from the photosensitive drums 1C, 1M, 1Y. The primary transfer rollers 31C, 31M, 31Y are photosensitive drums 1C, 9C, 9M, 9Y of the process cartridges 9C, 9M, 9Y arranged on the side of the opening 2 of the image forming apparatus main body other than the single color primary transfer roller 31K (other than the transfer unit). 1M and 1Y are provided facing each other.

  FIG. 1 shows the state of the primary transfer roller 31 and the intermediate transfer belt 18 in the full color mode. FIG. 2 shows the state of the primary transfer roller 31 and the intermediate transfer belt 18 in the monochrome mode.

  When the full color mode is selected, the second belt unit 36 rotates about the connection fulcrum 37 in the counterclockwise direction of FIG. Then, the primary transfer rollers 31C, 31M, and 31Y are urged toward the photosensitive drums 1C, 1M, and 1Y. Then, the photosensitive drums 1C, 1M and 1Y are brought into contact with the photosensitive drums 1C, 1M and 1Y through the intermediate transfer belt 18 with a predetermined contact pressure. At this time, in the first belt unit 35, the primary transfer roller 31K is urged in the direction of the photosensitive drum 1K at the fixed position, and is in contact with the photosensitive drum 1K through the intermediate transfer belt 18 with a predetermined contact pressure. .

  When the monochrome mode is selected, the second belt unit 36 rotates about the connection fulcrum 37 in the clockwise direction in FIG. 2, and the primary transfer rollers 31C, 31M, and 31Y move to the photosensitive drum 1C. , 1M, 1Y.

  As shown in FIG. 2, only the monochrome (black) primary transfer roller 31K comes into contact with the photosensitive drum 1K without being separated from the photosensitive drum 1K, and a monochrome image can be formed.

<Process cartridge replacement method>
A method for replacing the process cartridge 9 according to the present embodiment will be described with reference to FIGS. The cartridge tray 26 moves in the left-right direction in FIGS. 3 and 4 along the guide rail 27 while holding the process cartridge 9.

  The cartridge tray 26 is supported by a guide rail 27 with respect to the main body of the image forming apparatus, and is provided so as to be slidable in the left-right direction in FIGS. The cartridge tray 26 holds process cartridges 9K, 9C, 9M, and 9Y.

  In the state in which the monochrome mode is selected, as shown in FIGS. 2 and 3, the photosensitive drums 1C, 1M, and 1Y are lifted from the intermediate transfer belt 18, and the cartridge tray 26 can be pulled out from the image forming apparatus main body.

  As shown in FIG. 4, with the door 28 opened and the cartridge tray 26 pulled out along the guide rail 27, the upper surface of the process cartridge 9 is opened, and each process cartridge 9 can be removed.

  When the process cartridge 9 is mounted on the image forming apparatus main body, the process cartridge 9 is mounted on the cartridge tray 26 with the cartridge tray 26 pulled out, as shown in FIG. Then, the cartridge tray 26 is pushed in the left direction in FIG. 4 along the guide rail 27 to be stored inside the image forming apparatus main body.

  The monochrome (black) process cartridge 9K that holds the photosensitive drum 1K that is in contact with the intermediate transfer belt 18 in the monochrome mode is disposed on the farthest side (left side in FIG. 3) from the opening 2 of the image forming apparatus main body. . That is, it is the farthest side (left side in FIG. 3) from the opening 2 of the image forming apparatus main body with respect to the moving direction of the cartridge tray 26 (left and right direction in FIG. 3). Thereby, when the cartridge tray 26 is pulled out, a range where the photosensitive drum 1 and the intermediate transfer belt 18 are in contact with each other can be minimized.

<Switching to monochrome mode by automatic control>
In the present embodiment, the intermediate transfer belt 18 has a detection mechanism (not shown) that detects whether the intermediate transfer belt 18 is in a full color mode or a monochrome mode. Furthermore, a control (not shown) that automatically switches to the monochrome mode when the user is assumed to operate the cartridge tray 26, such as when the image forming operation is completed, or when the image forming apparatus main body is turned on or off. It has a mechanism. Then, before the main body of the image forming apparatus becomes ready for image forming operation, the second belt unit 36 rotates in the clockwise direction in FIG. 2 around the connection fulcrum 37 to rotate the primary transfer rollers 31C, 31M, 31Y. Are separated from the photosensitive drums 1C, 1M, 1Y to switch to the monochrome mode.

  The cartridge tray 26 can be pulled out along the guide rail 27 from the image forming apparatus main body at the position of the intermediate transfer belt 18 shown in FIGS.

  Next, the configuration of the second embodiment of the image forming apparatus according to the present invention will be described with reference to FIG. In addition, what was comprised similarly to the said 1st Embodiment attaches | subjects the same code | symbol, and abbreviate | omits description. In the first embodiment, switching between the full color mode and the monochrome mode is performed by automatic control by a control unit (not shown). In the present embodiment, switching between the full color mode and the monochrome mode is performed in conjunction with the user opening the door 28.

<Switching to monochrome mode by user operation>
In this embodiment, when the cartridge tray 26 is pulled out, the monochrome mode is forcibly switched by a user operation in order to surely switch the contact state between the photosensitive drum 1 and the intermediate transfer belt 18 to the monochrome mode.

  As in the first embodiment, the door 28 is provided so as to be rotatable with respect to the image forming apparatus main body, and FIG. 5 shows a state in which the door 28 is opened. A separation cam 38 that rotates in conjunction with the user opening the door 28 contacts a cam contact portion 36 a provided in the second belt unit 36.

  Then, the second belt unit 36 is rotated around the connecting fulcrum 37 in the clockwise direction of FIG. Accordingly, only the monochrome (black) primary transfer roller 31K disposed on the farthest side (left side in FIG. 5) from the opening 2 of the image forming apparatus main body is brought into contact with the photosensitive drum 1K with the intermediate transfer belt 18 interposed therebetween. . Then, the primary transfer rollers 31C, 31M, and 31Y are separated from the photosensitive drums 1C, 1M, and 1Y and switched to the monochrome mode.

  In the monochrome mode, the cartridge tray 26 is movably provided in a state where only the primary transfer roller 31K of the monochrome (black) is in contact with the photosensitive drum 1K of the process cartridge 9K of the monochrome (black) with the intermediate transfer belt 18 interposed therebetween. . The monochromatic (black) process cartridge 9K is disposed on the farthest side (left side in FIG. 5) from the opening 2 of the image forming apparatus main body.

  The primary transfer rollers 31C, 31M, 31Y are separated from the photosensitive drums 1C, 1M, 1Y by a separation cam 38 that rotates in conjunction with the opening operation of the door 28. This operation can be switched to the monochrome mode in which the intermediate transfer belt 18 is separated from the photosensitive drums 1C, 1M, and 1Y regardless of the mode state by the automatic control in the first embodiment.

  For this reason, even if the power is cut off during the printing operation, the intermediate transfer belt 18 may be separated from the photosensitive drums 1C, 1M, 1Y in conjunction with the opening / closing operation of the door 28 by the user. I can do it. The cartridge tray 26 can be pulled out from the image forming apparatus main body along the guide rail 27. Other configurations are the same as those in the first embodiment, and the same effects can be obtained.

1, 1K, 1C, 1M, 1Y ... photosensitive drum (image carrier)
2 ... Openings 9, 9K, 9C, 9M, 9Y ... Process cartridge
26 ... Cartridge tray (moving means)
31, 31K, 31C, 31M, 31Y ... Primary transfer roller (transfer means)

Claims (4)

A process cartridge having an image carrier on which an electrostatic latent image is formed, and image forming process means for developing the electrostatic latent image formed on the image carrier to form a toner image;
An image carrier belt disposed opposite to the image carrier;
A transfer unit disposed on the opposite side of the image carrier with the image carrier belt interposed therebetween, and transferring a toner image formed on the image carrier to the image carrier;
A plurality of the process cartridges can be detachably mounted, and the process cartridges can be linearly moved along the conveying direction of the image bearing belt to expose the process cartridges from the opening provided in the image forming apparatus main body. Transportation means;
A full color mode in which the transfer means for all colors are brought into contact with the image carrier with the image carrier belt in between, and a monochrome mode in which only the single color transfer means is brought into contact with the image carrier with the image carrier belt in between Mode switching means for switching between,
Have
The monochromatic process cartridge used for image formation in the monochrome mode is disposed farthest from the opening of the image forming apparatus main body with respect to the moving direction of the moving unit,
In the monochrome mode, only the single color transfer unit is in contact with the image carrier of the single color process cartridge disposed farthest from the opening of the main body of the image forming apparatus with the image carrier belt interposed therebetween. An image forming apparatus, wherein the moving means is movably provided in a state. The image carrier belt includes a first support portion provided opposite to the image carrier of the monochromatic process cartridge disposed farthest from the opening of the image forming apparatus main body, and the other The image forming apparatus main body is rotatably stretched by a second support portion that supports the transfer unit provided to face the image carrier of the process cartridge disposed on the opening side of the image forming apparatus main body,
The second support part is provided to be rotatable with respect to the first support part,
In the monochrome mode, only the single color transfer unit is in contact with the image carrier of the single color process cartridge disposed farthest from the opening of the main body of the image forming apparatus with the image carrier belt interposed therebetween. In the state, the second support part is rotated with respect to the first support part, and the process cartridge disposed on the opening side of the image forming apparatus main body other than the single color transfer unit 2. The image forming apparatus according to claim 1, wherein the transfer unit provided to face the image carrier is separated from the image carrier and the moving unit is movably provided. The mode switching unit is disposed on the farthest side from the opening of the image forming apparatus main body in the monochrome mode when the image forming apparatus main body is turned on, at the end of an image forming operation, or when the power is turned off. 3. The image forming apparatus according to claim 1, wherein only the single color transfer unit is in contact with the image carrier of the single color process cartridge with the image carrier belt interposed therebetween. A door capable of opening and closing the opening of the image forming apparatus main body is rotatably provided with respect to the image forming apparatus main body;
In conjunction with the opening operation of the door, only the single-color transfer means disposed farthest from the opening of the image forming apparatus main body is brought into contact with the image carrier with the image carrier belt interposed therebetween. Switch to monochrome mode,
In the monochrome mode, only the single color transfer unit is in contact with the image carrier of the single color process cartridge disposed farthest from the opening of the main body of the image forming apparatus with the image carrier belt interposed therebetween. The image forming apparatus according to claim 1, wherein the moving unit is movably provided in a state.

Images