JP4653401B2 - Process cartridge and image forming apparatus - Google Patents

Description

  The present invention relates to a unit support device and an image forming apparatus, and more particularly to a positioning mechanism of a process cartridge in which image forming devices related to image formation are collectively stored.

  In an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a printing machine, an electrostatic latent image formed on a photosensitive member that is a latent image carrier is subjected to a visible image processing by a developing device, and a visible image is obtained. A recording output can be obtained by transferring to a sheet or the like. As one type of such an image forming apparatus, there is known the above type configured as a copying machine, a printer, a facsimile, or a multifunction machine having at least two of these functions (for example, Patent Document 1). .

  In addition to the configuration in which one photoconductor is provided for only a single color, there is a configuration in which a plurality of photoconductors are provided for forming images of a plurality of colors. In the latter case, a multicolor image including a full color image is formed. Used in cases.

  For example, as a method for obtaining a full color image, a color image formed for each photoconductor is sequentially superimposed and transferred onto a conveyed sheet using a developer such as a toner having a color complementary to the color separation color. Alternatively, there is a system in which the color image for each photoconductor is sequentially transferred to the intermediate transfer body, and then the images superimposed and transferred on the intermediate transfer body are collectively transferred to the sheet.

  On the other hand, as one of the configurations in the case of using a plurality of photoconductors, in the configuration using the latter method among the above methods, a photoconductor that can form an image for each color is superimposed on an image from this photoconductor. A so-called tandem structure is known that is juxtaposed along a belt extending direction as an intermediate transfer member to be transferred (for example, Patent Document 2).

  In a configuration capable of forming images of a plurality of colors including a tandem structure, a photoconductor for image formation for each color and an image forming device for performing image forming processing on the photoreceptor are collectively accommodated in a cartridge, A configuration has been proposed in which this is incorporated in an image forming apparatus as a process cartridge for image formation (for example, Patent Document 2).

  Each image forming device accommodated in the process cartridge is required to be defined in the positional relationship in order to prevent the occurrence of a defective image. Therefore, conventionally, a configuration has been proposed in which each of the developing device and the cleaning device, for example, devices accommodated in the process cartridge can be positioned with respect to the photosensitive member (for example, Patent Document 1).

JP 2002-6679 A (page 3, FIG. 1) JP-A-10-39718 (paragraph "0034" column, "0041" column)

  When forming multiple color images with multiple process cartridges, when storing each process cartridge for incorporation into the image forming apparatus, the positional relationship between the photosensitive members between the process cartridges is specified. It is necessary to maintain a so-called positioned state in order to prevent a color shift due to a transfer shift between the color images.

  When the process cartridge is stored in the image forming apparatus, a guide rail provided in the image forming apparatus or a drawer member that can slide while holding the cartridge is used. In some cases, it is difficult to secure a space for providing a guide rail and a pull-out member between the process cartridges.

A configuration for defining the positional relationship of each image forming device with respect to the photosensitive member accommodated in the process cartridge, not the positioning between the process cartridges, is also shown in Patent Document 2 above. No measures have been taken.
Further, when the process cartridge is attached to and detached from the image forming apparatus using the guide rail, it is immediately determined at which position of the image forming apparatus main body the guide rail that may be a relatively heavy object is provided. Although it is necessary to fit the sliding part on the process cartridge side to the guide rail, it may be difficult for general users to find the position of the guide rail immediately, and the process cartridge mounting work may be troublesome. is there.

  In view of the problems in the conventional process cartridge and the image forming apparatus including the same, the object of the present invention is to reduce the installation space when a plurality of process cartridges are arranged and the space occupied by the process cartridge. An object of the present invention is to provide a process cartridge and an image forming apparatus having a configuration capable of optimizing the positioning of the process cartridges and simplifying the mounting operation.

The invention described in claim 1 includes a cartridge having an image carrier on which a toner image is formed, and image formation for obtaining a recorded image by transferring the toner image formed on the image carrier to a transfer material In the image forming apparatus, wherein the cartridge is configured to be detachable from the image forming apparatus main body in the axial direction of the image carrier, the transfer material is the image carrier of each process cartridge. The intermediate transfer belt is in contact with the image forming apparatus , and is positioned so as to be flat and substantially parallel to the running side of the intermediate transfer belt, which supports and guides the flat lower surface portion of the cartridge case from below when the cartridge is attached to and detached from the image forming apparatus main body. A guide having a support surface and when the process cartridge is attached / detached, the process cartridge moves in a direction perpendicular to the attaching / detaching direction. A restricting means for restricting, and the restricting means includes a restricting portion protruding upward with respect to the support surface, and the restricting means protrudes upward from the support surface and constitutes a restricting portion. comprising a vertical guide portion partially bent, upper and lower guide portion, the detachable direction of the length of the process cartridge is set shorter than the length of the detachable direction of the process cartridge, said at desorption of the process cartridge It is characterized by restricting the upward movement of the process cartridge.

According to a second aspect of the present invention, when the process cartridge is mounted in the main body of the image forming apparatus, the vertical guide portion is configured to regulate the upward movement of the process cartridge halfway. A bulging portion that protrudes upward from the support surface is provided in a portion on the back side in the process cartridge detaching direction.

According to a third aspect of the present invention, there is provided a positioning portion for positioning the process cartridge in the longitudinal direction when the process cartridge is mounted in the image forming apparatus main body.

According to a fourth aspect of the present invention, the process cartridge has a handle rotatably connected between the use position and the storage position with respect to the unit case, and the handle is brought to the use position. In this case, the handle is released from the longitudinal positioning of the process cartridge.

According to the first and second aspects of the present invention, the length of the vertical guide portion for guiding the bond for the process cartridge attaching / detaching operation is set to be shorter than the length of the support surface in the longitudinal direction of the image forming apparatus main body. By this, when the process cartridge is attached or detached, the upward movement of the process cartridge can be restricted to prevent damage due to contact between the image carrier and the intermediate transfer belt, and the insertion can be completed while the movement to the information is restricted. At that time, the process cartridge can be lifted upward by the bulging portion to enable contact between the two members.

According to the third aspect of the invention, since the positioning in the longitudinal direction corresponding to the attaching / detaching direction of the process cartridge can be performed, the positioning can be performed at a predetermined position. The positional relationship between the body and the transfer body disposed in the vicinity of the process cartridge can be set under a predetermined condition.

According to the fourth aspect of the present invention, a handle capable of being connected to the road is provided at the use position and the collection position, and the positioning is canceled simply by rotating the process cartridge to the use position, that is, the position for attaching / detaching the process cartridge. Therefore, only when the process cartridge is attached or detached, it is possible to set a state in which the attachment or detachment operation can be performed using a member included in the process cartridge that is the attachment and detachment operation target.

  The best mode for carrying out the present invention will be described below with reference to the illustrated embodiments.

FIG. 1 is a schematic diagram showing an example of an image forming apparatus using a process cartridge according to an embodiment of the present invention . The image forming apparatus shown in FIG. 1 is a color printer that can form a full-color image using a tandem method. is there. In the present invention, not only the printer shown in FIG. 1 but also a copying machine, a facsimile machine, a printing machine or the like is included as an image forming apparatus.

In FIG. 1, the image forming apparatus 120 includes the following apparatuses.
Image forming devices 121Y, 121C, 121M, and 121K that form images of respective colors according to the document image, transfer devices 122 that are disposed to face the image forming devices 121Y, 121C, 121M, and 121K, and the respective image forming devices A manual feed tray 123 as a sheet supply means for supplying a recording sheet to a transfer area where the apparatuses 121Y, 121C, 121M, 121K and the transfer device 122 face each other; a paper feed cassette 124A provided in the paper feed device 124; A registration roller 130 that supplies the recording sheet conveyed from the tray 123 or the paper feed cassette 124 in accordance with the image forming timing of the image forming apparatuses 121Y, 121C, 121M, and 121K, and fixing of the sheet-like medium after transfer in the transfer region. The fixing device 110 performs the above.
Although not described in detail, the fixing device 110 undergoes processes of melting and softening and permeating the image by the action of heat and pressure using a heating roller and a pressure roller that can face each other across the conveyance path of the recording sheet. A heat roller fixing method for fixing to a recording sheet is used.

The transfer device 122 uses a belt 122A (hereinafter referred to as a transfer belt) that is wound around a plurality of rollers as a transfer body, and applies a transfer bias to a position facing the photosensitive drum in each image forming device. The transfer bias means 122Y, 122C, 122M, and 122K are arranged so that toner images formed by the respective image forming devices are sequentially superimposed and transferred by applying a transfer bias having a polarity opposite to that of the toner.
In the transfer device 122, a secondary transfer bias unit 122F for collectively transferring the toner images superimposed and transferred onto the transfer belt 122A to the recording sheet is disposed on the recording sheet conveyance path.

The image forming apparatus 120 has a larger heat capacity than that of paper such as plain paper generally used for copying, 90 K paper such as an OHP sheet, card, postcard, thick paper equivalent to a basis weight of about 100 g / m ² or more, and an envelope. Any so-called special sheet can be used as the recording sheet.

In FIG. 1, each of the image forming apparatuses 121Y, 121C, 121M, and 121K develops colors of yellow, cyan, magenta, and black, respectively, and uses the same toner color, but has the same configuration. The configuration of the image forming device 121K will be described as a representative of the image forming devices 121Y, 121C, 121M, and 121K.
The image forming device 121K includes a photosensitive drum 125K as an electrostatic latent image carrier, a charging device 127K, a developing device 126K, and a cleaning device 128K that are sequentially arranged along the rotation direction of the photosensitive drum 125K. A configuration is used in which an electrostatic latent image is formed between the device 127K and the developing device 126M according to image information corresponding to the color separated by the writing light 129K from the writing device 129. In addition to the drum shape, the electrostatic latent image carrier may have a belt shape. The image forming devices arranged around these photosensitive drums, in other words, the image forming devices are collectively contained in a process cartridge (indicated by reference numeral PC for convenience) having a unit structure having a housing shown in FIG. It is stored in.
In the image forming apparatus 120 shown in FIG. 1, since the transfer device 122 extends obliquely, the space occupied by the transfer device 122 in the horizontal direction can be reduced.

In the image forming apparatus 120 having the above configuration, image formation is performed based on the following steps and conditions. In the following description, an image forming apparatus that forms an image using the black toner denoted by reference numeral 121K on behalf of each image forming apparatus will be described, but the same applies to other image forming apparatuses. Preface.
At the time of image formation, the photosensitive drum 125K is rotationally driven by a main motor (not shown), is neutralized by an AC bias (DC component is zero) applied to the charging device 127K, and its surface potential is set to a reference potential of about −50V. Is done.
Next, the photosensitive drum 125K is uniformly charged to a potential substantially equal to the DC component by applying a DC bias superimposed with an AC bias to the charging device 127K, and the surface potential thereof is approximately −500 V to −700 V (target). The charging potential is determined by a process control unit).

  When the photosensitive drum 125K is uniformly charged, a writing process is executed. An image to be written is written for forming an electrostatic latent image using a writing device 129 in accordance with digital image information from a controller unit (not shown). That is, in the writing device 129, laser light from a laser light source that emits light based on a laser diode light emission signal binarized for each color corresponding to digital image information is converted into a cylinder lens (not shown), a polygon motor 129A, A photosensitive drum that carries an image for each color via the fθ lens 129B, the first to third mirrors, and the WTL lens. In this case, for convenience, the photosensitive drum 125K is irradiated with the irradiated portion. The surface potential on the surface of the photosensitive drum becomes approximately −50 V, and an electrostatic latent image corresponding to the image information is formed.

  The electrostatic latent image formed on the photosensitive drum 125K is subjected to visible image processing using a toner having a color complementary to the color separation color by the developing device 126K. In the developing process, an AC bias is applied to the developing sleeve. The toner (Q / M: -20 to -30 μC / g) is developed only in the image portion where the potential is lowered by the irradiation of the writing light by applying DC: −300 V to −500 V with the superimposed toner, and the toner image Is formed.

Each color toner image that has undergone a visible image process in the development process is transferred to a recording sheet that is fed out with registration timing set by a registration roller 130. The recording sheet is transferred to a roller before reaching the transfer belt 122A. The sheet is biased electrostatically to the transfer belt 122A by application of a suction bias by the sheet suction bias means configured as described above.
The transfer belt 122A is separated from the photosensitive drum by applying a bias having a polarity opposite to that of the toner by the transfer bias means 122Y, 122C, 122M, and 122BK provided in the transfer device 122 at a position facing the photosensitive drum in each image forming device. The toner image is electrostatically transferred and the superimposed toner image is collectively transferred to the recording sheet by the secondary transfer bias unit 122F.

The recording sheet that has undergone the transfer process for each color is separated from the transfer belt 122A by a driving roller of the transfer belt unit (indicated by reference numeral 122A1 in FIG. 1 for convenience), conveyed toward the fixing device 110, and added to the fixing belt 110. By passing through a fixing nip composed of a pressure roller, the toner image is fixed on the recording sheet and discharged to the paper discharge tray 132.
The image forming apparatus 120 shown in FIG. 1 can perform not only image formation on one side of a recording sheet discharged after fixing but also image formation on both sides. The recording sheet after fixing is conveyed to the reverse circulation path RP, and is fed toward the registration roller 130 by a feeding roller RP1 that is positioned at the end of the circulation path and also serves to feed out the sheet from the manual feed tray 123. Switching of the recording sheet conveyance path during image formation on one side and both sides is performed by a conveyance path switching claw RP2 disposed behind the fixing device 110.

  The physical properties including the above-described charging potential are not limited to the above values, and can of course be changed according to color, density, and the like. In FIG. 1, reference numerals T1 to T4 denote toner supply tanks used in the developing device.

FIG. 2 is a diagram for explaining the configuration of the process cartridge PC. In FIG. 2, the process cartridge PC is composed of, for example, a resin-molded housing, and an image formation for creating a black image now is performed. When the apparatus is described as an object, the housing wall facing the transfer belt 122A has an opening PC1 for exposing a part of the photosensitive drum 125K, and the housing wall facing the writing device 129 side has writing. An introduction port PC2 for the light 129K is formed.
In the process cartridge PC, the attachment / detachment direction is set in the axial direction corresponding to the longitudinal direction of the photosensitive drum 125K, and in this embodiment, the direction perpendicular to the paper surface shown in FIG. 2 is set as the attachment / detachment direction. Therefore, it can be pulled out to the front side of the paper for maintenance and inspection.

2 and 3, guide portions 1000 and 1001 are provided on the upper wall PC3 of the developing device 126K and the bottom wall PC4 of the cleaning device 128K, which are the outer walls of the process cartridge PC and that face the adjacent process cartridge. Is provided. In FIG. 3, the process cartridge for magenta is omitted.
As shown in FIG. 3, a guide portion G1 for guiding the guide portion 1000 is an image on the left side of the process cartridge PC used for yellow (Y) image formation provided on the leftmost side. It is provided in the forming apparatus 120 and can guide when the process cartridge is attached or detached. Similarly, a guide part G2 for guiding the guide part 1001 is provided on the image forming apparatus 120 on the right side of the process cartridge PC used for the black (K) image formation provided on the rightmost side in FIG. A guide is provided when the process cartridge is attached or detached.
The guide parts 1000 and 1001 are provided in a state of facing the process cartridges arranged at adjacent positions. One of the guide parts 1000 and 1001 is formed as a convex part so that the other 10001 is a male member, and the other 1001 is a female member. Thus, it is set as the structure provided with the recessed part of the shape which can accept one 1000. The guide portions 1000 and 1001 are formed to have a length in a direction perpendicular to the paper surface so as to cover a moving stroke when the process cartridge PC is attached / detached.

  Since the guide parts 1000 and 1001 are configured by a relationship of a male member and a female member, they can be fitted to each other as shown in FIG. Since the guide portion 1000 constituted by the convex portion is included in the other guide portion 1001 in which a part of the protruding length becomes a female member, the guide portion 1000 is more than the interval between the process cartridges due to the protruding length when not fitting. The interval between process cartridges when fitted can be shortened. In FIG. 4, the process cartridge for magenta is omitted.

  The guide portions 1000 and 1001 in the fitted state are in a state of abutting against the wall surfaces of the adjacent process cartridges, whereby the facing interval between the process cartridges PC is defined and the process cartridges can be positioned. ing.

  The guide portions 1000 and 1001 may be formed separately from the casing of the process cartridge PC and may be retrofitted to the casing or may be integrally formed with the casing. In the case of retrofitting, bonding or fastening is used for the housing.

In the configuration as described above, when the process cartridge PC is moved with respect to the inside of the image forming apparatus 120, the guides 1000 and 1001 provided in the process cartridge PCs arranged at adjacent positions are used. In particular, when loaded in the image forming apparatus 120, the opposed positions of the guide portions 1000 and 1001 are defined and positioned. Note that the guide portions 1000 and 1001 are portions that enable movement while supporting the weight of the process cartridge PC, so that the process cartridge can be located at a relatively distant position with respect to the vertical center of the process cartridge PC. The PC can be slid without generating any couple by receiving gravity at a relative position in the horizontal direction. Needless to say, an extra external force in the horizontal direction can be obtained by setting the dimensions of the installation positions of the guide parts 1000, 1001 in the horizontal direction of the process cartridge PC to dimensions that allow the guide parts 1000, 1001 to be fitted. The sliding is performed smoothly without adding. As a result, there is no need to provide a process cartridge PC moving guide portion or positioning portion in the image forming apparatus. Unlike these cases, the space occupied by the process cartridge PC is reduced and the apparatus is downsized. Can be planned.

Next, a partially modified configuration of the above configuration will be described.
In FIG. 5, the guide portions (indicated by reference numerals 1000 ′ and 1001 ′ for convenience) have different shapes of end portions to be fitted for each process cartridge PC.
In the embodiment shown in FIG. 4, the guide portion 1000 ′ in the left process cartridge PC has a convex tip with an inclined surface, and the guide portion 1001 ′ has an arc-shaped recess, and in the process cartridge PC shown in the center. The guide portion 1000 ′ has an arcuate convex tip that can be fitted into the guide portion 1001 ′ in the left process cartridge PC, the guide portion 1001 ′ has a rectangular recess, and the process shown on the right side. The guide portion 1000 ′ of the cartridge PC has a rectangular convex tip so that the guide portion 1000 ′ can be fitted into the guide portion 1001 ′ of the central process cartridge PC, and the guide portion 1001 ′ is a rectangular concave portion.

In the configuration described above, when an image of a different color is formed for each process cartridge, the installation position of the process cartridge PC is not erroneous. That is, since the process cartridge PC can be loaded only at the position where the fitting shapes of the guide portions 1000 ′ and 1001 ′ are aligned, the installation position of the process cartridge PC set in consideration of the transfer order is inevitably determined. Will be. As a result, the process cartridge PC stored in the image forming apparatus can be identified by the guide portions 1000 ′ and 1001 ′.

Next will be explained the features of the present invention as a target of the above-described configuration.
FIG. 6 is a vertical cross-sectional view showing an example of an image forming apparatus that forms a full-color image. The image forming apparatus shown here is a first drum-shaped photosensitive member disposed in the image forming apparatus main body 1. Or the fourth image carrier 2Y, 2C, 2M, 2BK, and the endless intermediate transfer belt 3 disposed in the image forming apparatus main body 1. The intermediate transfer belt 3 is wound around the support rollers 4, 5, 6 and is driven to rotate in the direction of arrow A.

  The intermediate transfer belt 3 is positioned above the image carriers 2Y to 2BK, and the lower running side of the intermediate transfer belt 3 is in contact with the peripheral surface of the image carriers 2Y to 2BK. The intermediate transfer belt 3 constitutes an example of a transfer material onto which toner images of different colors formed on the surface of each image carrier are transferred in a superimposed manner.

  The configuration in which a toner image is formed on each of the first to fourth image carriers 2Y, 2C, 2M, and 2BK and the toner image is transferred to the intermediate transfer belt 3 is substantially different only in the color of the toner image. Since all of them are the same, only a configuration in which a toner image is formed on the first image carrier 2Y and the toner image is transferred to the intermediate transfer belt 3 will be described.

FIG. 7 is an enlarged view showing the image carrier 2Y and each image forming device for forming a toner image on the surface of the image carrier 2Y.
The image carrier 2Y is driven to rotate clockwise in FIG. 7, and at this time, the image carrier 2Y is charged to a predetermined polarity by a charging device including a charging roller 7Y to which a charging voltage is applied. The charged image carrier 2Y is irradiated with a light-modulated laser beam L emitted from the optical writing device 8 shown in FIG. 6, thereby forming an electrostatic latent image on the image carrier 2Y. This electrostatic latent image is visualized as a yellow toner image by the developing device 9Y.

  The developing device 9Y is disposed so as to face the image carrier 2Y in close proximity to the developing case 10Y containing the dry developer D, and rotatably supported by the developing case 10Y, and through an opening formed in the developing case. The developing roller 11Y, the developing blade 31Y for regulating the amount of developer on the developing roller 11Y, and the first and second conveying screws 32Y and 33Y disposed to face the developing roller 11Y are provided. The developer D in the developing case 10Y is stirred while being conveyed by the first and second conveying screws 32Y and 33Y, and is carried and conveyed on the developing roller 11Y that rotates in the direction of the arrow. At this time, the height of the developer on the developing roller 11Y is regulated to be constant by the developing blade 31Y, and the regulated developer is conveyed to the developing area between the developing roller 11Y and the image carrier 2Y, where development is performed. The toner in the agent is electrostatically transferred to an electrostatic latent image formed on the image carrier, and the latent image is visualized as a toner image. As the developer, either a one-component developer or a two-component developer can be used. Here, a two-component developer having a toner and a carrier is used.

  A primary transfer roller 12Y is disposed on the opposite side of the image transfer body 2Y with the intermediate transfer belt 3 interposed therebetween, and a transfer voltage is applied to the primary transfer roller 12Y, so that the toner image on the image support 2Y is changed to an arrow. Primary transfer is performed on the intermediate transfer belt 3 rotating in the A direction. The transfer residual toner adhering to the image carrier 2Y after the toner image transfer is removed by the cleaning device 13Y.

  The cleaning device 13Y of this example includes a cleaning case 34Y having an opening on the side facing the image carrier 2Y, a base end portion fixedly supported by the cleaning case 34Y, and a tip portion pressed against the surface of the image carrier 2Y. A cleaning blade 35Y that removes the transfer residual toner on the image carrier 2Y and a waste toner screw 36Y that transports the removed toner to a waste toner bottle (not shown). Since a charging voltage in which an alternating current component is superimposed on a direct current is applied to the charging roller 7Y, when the image carrier 2Y that has passed through the cleaning device 13Y passes through the charging roller 7Y, it is charged at the same time as the charge removal, and the next operation is performed. Prepare for the statue.

  In the same manner as described above, a cyan toner image, a magenta toner image, and a black toner image are respectively formed on the second to fourth image carriers 2C, 2M, and 2BK shown in FIG. Are sequentially superposed on the intermediate transfer belt 3 to which the yellow toner image has been transferred, and are primarily transferred to form a composite toner image on the intermediate transfer belt 3. The transfer residual toner on each of the image carriers 2C, 2M, 2BK after the toner image transfer is removed by the cleaning device is the same as in the case of the first image carrier 2Y.

  As shown in FIG. 6, there are image forming apparatuses that operate in the same manner as the respective image forming apparatuses provided around the first image carrier 2Y around the second to fourth image carriers 2C, 2M, and 2BK. In FIG. 6, for these image forming apparatuses, C, M, and BK are used instead of the symbol Y attached to the image forming apparatus provided around the first image carrier 2Y. The code | symbol which attached | subjected is attached | subjected.

  On the other hand, as shown in FIG. 6, a paper feed cassette 14 containing a recording medium P made of, for example, transfer paper, and a paper feed device 16 having a paper feed roller 15 are arranged in the lower part of the image forming apparatus main body 1. The uppermost recording medium P is sent out in the arrow B direction by the rotation of the paper feed roller 15. The fed recording medium is fed by the registration roller pair 17 between the portion of the intermediate transfer belt 3 wound around the support roller 4 at a predetermined timing and the secondary transfer roller 18 disposed on the intermediate transfer belt 3. The At this time, a predetermined transfer voltage is applied to the secondary transfer roller 18, whereby the composite toner image on the intermediate transfer belt 3 is secondarily transferred to the recording medium P.

  The recording medium P on which the composite toner image has been secondarily transferred is further conveyed upward and passes through the fixing device 19, and at this time, the toner image on the recording medium P is fixed by the action of heat and pressure. The recording medium P that has passed through the fixing device 19 is discharged by the paper discharge roller pair 20 to the paper discharge unit 22 at the top of the image forming apparatus main body 1. Further, the transfer residual toner adhering to the intermediate transfer belt 3 after the toner image transfer is removed by the cleaning device 24.

  Toner bottles 37Y, 37C, 37M, and 37BK containing toners of yellow, cyan, magenta, and black are disposed in the upper part of the image forming apparatus main body 1 and above the process cartridges 40Y to 40BK, which will be described later. The toner bottles 37Y to 37BK are detachably attached to the image forming apparatus main body 1, and the respective color toners are replenished to the developing devices 9Y, 9C, 9M, and 9BK through conveyance paths (not shown). Is done.

  By the way, the charging device including the charging roller 7Y shown in FIG. 7, the developing device 9Y, and the cleaning device 13Y constitute an image forming device for forming a toner image on the image carrier 2Y. The same applies to the charging rollers 7C, 7M, 7BK, the developing devices 9C, 9M, 9BK and the cleaning devices 13C, 13M, 13BK provided around the image carriers 2C, 2M, 2BK.

  Here, each image carrier 2Y to 2BK on which a toner image is formed on the surface and at least one image forming device for forming the toner image on each image carrier are integrally assembled. Constructed as cartridges 40Y, 40C, 40M, and 40BK, the image forming apparatus of this example has a plurality of such process cartridges, and transfers toner images of different colors respectively formed on the respective image carriers 2Y to 2BK. The recording image is obtained by transferring to an intermediate transfer belt 3 which is an example of the material.

  In the image forming apparatus of this example, as shown in FIG. 7, the developing case 10Y and the cleaning case 34Y are formed as a unit case 41Y, and the image carrier 2Y is rotatably supported by the unit case 41Y. The image carrier 2Y, the developing device 9Y, the cleaning device 13Y, and the charging roller 7Y are integrally assembled to form a process cartridge 40Y. The same process cartridges 40C, 40M, and 40BK are configured by the other image carriers 2C, 2M, and 2BK and the image forming devices provided around the image carriers 2C, 2M, and 2BK, respectively.

  As described above, instead of integrating the image carrier, the charging device, the developing device, and the cleaning device together to form the process cartridge, the process cartridge may be constituted by the image carrier and some image forming devices. Good. For example, a process cartridge can be configured by an image carrier, and at least one of a charging device, a developing device, and a cleaning device for forming a toner image on the image carrier.

As shown in FIG. 6, the intermediate transfer belt 3 is disposed in an inclined state in which the right end side in the drawing is low and the left end side is high, and each of the image carriers 2Y to 2BK is disposed below the intermediate transfer belt 3. It is arranged along the running side. Each of the image carriers 2Y to 2BK is arranged in an oblique direction in the vertical direction along the surface moving direction of the intermediate transfer belt 3 which is an example of the transfer material. 40BK is arranged in the diagonal direction. In addition, each of the process cartridges 40Y to 40BK is configured to be attachable to and detachable from the image forming apparatus main body 1 in a direction perpendicular to the paper surface of FIGS.
In the illustrated example, the process cartridges 40Y to 40BK are attached and detached in the axial direction of the image carriers 2Y to 2BK.

  Here, as shown in FIGS. 6 and 7, guides 42Y, 42C, 42M, and 42BK fixed to the image forming apparatus main body 1 are provided in the image forming apparatus main body 1, and the guides 42Y to 42BK are provided. Includes support surfaces 43Y, 43C, 43M, and 43BK that support and guide the process cartridges from below when the process cartridges 40Y to 40BK are attached to and detached from the image forming apparatus main body 1. The support surfaces 43Y to 43BK of the guides 42Y to 42BK have different height positions corresponding to the height positions of the process cartridges.

  In the image forming apparatus shown in FIGS. 6 and 7, the support surfaces 43Y, 43C, 43M, and 43BK are arranged almost horizontally, and the support surfaces are arranged stepwise.

  In each of the guides 42Y to 42BK and the unit cases 41Y, 41C, 41M, and 41BK of the process cartridges 40Y, 40C, 40M, and 40BK, the laser beam L emitted from the optical writing device 8 reaches the image carriers 2Y to 2BK. As can be seen, light transmission windows 44Y, 44C, 44M, and 44BK are formed.

  Further, the front plate of the image forming apparatus main body 1 is disposed on the front side of each element such as the process cartridges 40Y to 40BK, the intermediate transfer belt 3, and the optical writing device 8 (not shown in FIGS. 6 and 7, but see FIG. 10). However, an opening 45 indicated by a two-dot chain line in FIG. 6 is formed in the front side plate, and the process cartridges 40Y to 40BK can be attached and detached through the opening 45.

  As shown in FIG. 10, a face plate 51 is disposed on the front side plate 50 of the image forming apparatus main body 1, and this face plate 51 is located between the open position shown in FIG. 10 and the closed position where the opening 45 is closed. Is connected to the front side plate 50 in a rotatable manner. When the process cartridges 40Y, 40C, 40M, and 40BK are mounted in the image forming apparatus main body 1 and the face plate 51 is moved to the closed position, the face plates 51 allow the image carriers 2Y to 2BK of the process cartridges 40Y to 40BK to be moved. Finally, the positioning is performed, and the image forming operation can be performed in this state.

  According to the above-described configuration, when the process cartridges 40Y to 40BK are inspected, repaired, or replaced, the process cartridges are placed on the support surfaces 43Y to 43BK, and the process cartridges are placed on the front side. The process cartridges can be pulled out or pushed inward, and the process cartridges can be attached and detached while being kept horizontal. Therefore, unlike the prior art, there is no need to fit the movable rail provided in each process cartridge to the guide rail provided in the image forming apparatus main body. Moreover, if the door (not shown) of the main body of the image forming apparatus is opened and the face plate 51 is rotated to the open position, the support surfaces 43Y to 43BK of the guides 42Y to 42BK can be immediately visually confirmed. It can be understood that each process cartridge can be guided by 43Y to 43BK and can be detached. For this reason, even a general user can easily remove and attach each process cartridge, and each process cartridge can be kept in a horizontal state at the time of removal, so that the operation can be performed more easily.

  Further, if a restricting means is provided for restricting the movement of the process cartridge in a direction perpendicular to the removal direction when the process cartridge is detached, the process cartridge is positioned next to the process cartridge when it is removed. Interference with the process cartridge can be prevented, and problems that the process cartridge is damaged can be prevented.

  For example, as shown in FIGS. 6 and 7, the guides 46Y protrude from the support surfaces 43Y to 43BK and extend in the attaching / detaching direction of the process cartridge (see FIG. 7 for details). And a groove 48 (see also FIG. 7) formed in the unit cases 41Y to 41BK of the process cartridges 40Y to 40BK is slidably fitted to the guide protrusions 46. This prevents the process cartridge from moving greatly in the horizontal direction when the cartridge is detached. Of course, each process cartridge is provided with a guide projection, and each guide is formed with a guide groove into which the guide projection is slidably fitted. By means of a regulation means comprising the guide projection and the guide groove, the process cartridge is attached and detached. Sometimes this may be prevented from moving significantly in the horizontal direction.

  Further, as shown in FIG. 7, a protrusion 52Y is provided on the side of the unit case 41Y opposite to the guide protrusion 46, and the protrusion 52Y rises with respect to the support surface 43Y when the process cartridge 40Y is attached or detached. The wall 53 can be rubbed to prevent the process cartridge 40Y from shifting. The protrusion 52Y and the wall 53 also constitute an example of a restricting means, and such a restricting means can be attached to the other process cartridges 40C, 40M, and 40BK.

  As shown in FIG. 8, the guides 42Y to 42BK are provided with guide protrusions 46Y to 46BK having different forms and mounting positions, and the process cartridges 40Y to 40BK are fitted to the guide protrusions 46Y to 46BK. Guide grooves can also be formed. FIG. 9 shows an example in which a guide groove 47Y that can be fitted to the guide protrusion 46Y located on the leftmost side in FIG. 8 is formed in the unit case 41Y of the process cartridge 40Y.

  If configured as described above, for example, the guide groove 47Y of the process cartridge 40Y shown in FIG. 9 cannot be fitted into the other guide protrusions 46C, 46M, and 46BK, so that the process cartridge 40Y is set at an incorrect position. There is no end. Only the regular process cartridges 40Y to 40BK can be set in the guides 42Y to 42BK. A guide groove may be formed in each guide, and a guide protrusion may be provided in each process cartridge so that erroneous setting of the process cartridge can be prevented in the same manner.

  As described above, if the restricting means has an erroneous setting prevention function for prohibiting the mounting of process cartridges other than the regular process cartridge, the erroneous setting of the process cartridge can be prevented in advance. Incorrect color toner can be replenished, and a problem that the image quality of the toner image deteriorates due to color mixture can be prevented.

  Further, the guides 42Y to 42BK can be supported by an elevating device (not shown) so as to be movable up and down. With this configuration, when the process cartridge is attached or detached, the process cartridge can be lowered and the image carrier can be reliably separated from the intermediate transfer belt 3, so that the slide between the image carrier and the intermediate transfer belt 3 can be performed. By rubbing, it is possible to prevent a problem that these surfaces are damaged.

  At this time, the whole of the plurality of guides 42Y to 42BK may be configured to move up and down integrally, but the guides 42Y to 42BK for guiding the process cartridges 40Y to 40BK can move up and down independently. In this case, only the necessary guide can be moved up and down, so that the process of detaching the process cartridge can be simplified.

  Further, as described above, in the image forming apparatus of this example, each process cartridge 40Y to 40BK has developing devices 9Y to 9BK that form toner images on the image carriers 2Y to 2BK, and each of the developing devices 9Y to 9BK. Toner bottles 37Y, 37C, 37M, and 37BK containing toner supplied to the devices 9Y to 9BK are detachably attached to the image forming apparatus main body 1 separately from the process cartridges 40Y to 40BK. Therefore, the user usually only needs to replace the toner bottles 37Y to 37BK, and only needs to replace the process cartridges 40Y to 40BK when it is necessary to replace them. When the toner runs out, there is no need to replace even the process cartridge, so the economic burden on the user can be reduced.

  FIG. 11 is a schematic diagram showing another example of the image forming apparatus, and the basic configuration of the image forming apparatus shown here is the same as that of the image forming apparatus shown in FIGS. That is, the image forming apparatus shown in FIG. 11 is also a process cartridge in which an image carrier on which a toner image is formed and at least one image forming device for forming a toner image on the image carrier are integrally assembled. A plurality of 40Y, 40C, 40M, and 40BK, each configured to transfer a toner image of a different color formed on each image carrier onto a transfer material including an intermediate transfer belt to obtain a recorded image; Each of the process cartridges 40Y to 40BK is arranged in an oblique direction and is configured to be detachable from the image forming apparatus main body 1. In addition, when the process cartridges 40Y to 40BK are attached to and detached from the image forming apparatus main body 1, the guides 42Y, 42C, 42M, and 42BK having the support surfaces 43Y, 43C, 43M, and 43BK that support and guide the process cartridges 40Y to 40BK from below. The support surfaces 43Y to 43BK have different height positions.

  In FIG. 11, the intermediate transfer belt is shown in a state of being accommodated in the case, and the belt is not shown in the drawing. Similarly to the intermediate transfer belt 3 shown in FIG. 6, this intermediate transfer belt is also arranged with its lower running side at an angle of about 15 degrees with respect to the horizontal plane, and each process cartridge 40Y is mounted on the intermediate transfer belt 3. A toner image is transferred from an image carrier of 40 to 40BK, and the toner image is transferred to a recording medium.

  12 is a view showing the image forming apparatus main body after the process cartridges 40Y to 40BK shown in FIG. 11 are taken out. As can be seen from this figure, this image forming apparatus is different from the image forming apparatus shown in FIGS. 6 and 7 in that the support surfaces 43Y to 43BK of the respective guides 42Y to 42BK are inclined. is there.

  In this example as well, the transfer material onto which the toner images of the respective colors formed on the respective image carriers are transferred consists of an intermediate transfer belt with which the image carrier of each process cartridge abuts, but the respective support surfaces 43Y to 43BK are intermediate. It is located substantially parallel to the lower running side of the transfer belt. Each process cartridge 40Y to 40BK is mounted in the image forming apparatus main body 1 or pulled out from the image forming apparatus main body 1 as indicated by arrows E and F in FIG. 12 while being guided by the supporting surfaces 43Y to 43BK. . Light transmissive windows 44Y to 44BK through which a laser beam emitted from the optical writing device passes are formed on the support surfaces 43Y to 43BK.

  FIG. 14 is a perspective view showing the process cartridges 40Y to 40BK, and FIG. 15 is a front view showing the process cartridges 40Y to 40BK mounted on the image forming apparatus main body guided by the guides 42Y to 42BK. 16 and 17 are perspective views showing the front side of the process cartridges 40Y to 40BK mounted in the main body of the image forming apparatus. 14 and 17, arrows E and F also indicate the direction when the process cartridge is pushed into the image forming apparatus main body and mounted, and the direction when the process cartridge is pulled out from the image forming apparatus main body, as in FIG. Yes.

  The image forming apparatus shown in FIGS. 11 and 12 is also provided with restricting means for restricting the process cartridge from moving in a direction perpendicular to the attaching / detaching direction when the process cartridge is attached / detached. As shown in FIG. 13, the restricting means has restricting portions 54Y, 54C, 54M, and 54BK made of a plate material that rises substantially perpendicularly upward with respect to the support surfaces 43Y to 43BK. Guides 42Y to 42BK having substantially L-shaped cross sections are constituted by the surface and the restricting portion.

  When the process cartridges 40Y to 40BK are attached to and detached from the image forming apparatus main body 1 as indicated by arrows F and E, the support surfaces 43Y to 43BK guide the substantially flat bottom surfaces of the process cartridges 40Y to 40BK. However, at this time, the process cartridges 40Y to 40BK come into contact with the restricting portions 54Y to 54BK by their own weights. When the process cartridges 40Y to 40BK are attached and detached, the restricting portions 54Y to 54BK support the side portions of the process cartridges and restrict the displacement movement of the process cartridges in the width direction W (see FIG. 14). In this manner, the process cartridges 40Y to 40BK are smoothly attached to and detached from the image forming apparatus main body without being shifted in the width direction W by the guides 42Y to 42BK. Note that the width direction W of the process cartridge is a width in a direction orthogonal to the longitudinal direction L of each of the process cartridges 40Y to 40BK, as shown in FIG.

  By the way, when the process cartridges 40Y to 40BK are attached to and detached from the image forming apparatus main body 1, if the image carrier of the process cartridge hits the intermediate transfer belt and rubs, the surface of the image carrier or the intermediate transfer belt is contacted. There is a risk of scratching.

  Therefore, as shown in FIGS. 12 and 13, the restricting means of the image forming apparatus of the present example includes upper and lower guide portions 55Y, 55C that restrict upward movement of the process cartridges 40Y to 40BK. 55M, 55BK. In the example shown here, plate-like vertical guide portions 55Y to 55BK are formed by cutting and raising part of the restricting portions 54Y to 54BK made of a plate material such as a sheet metal. Each of the vertical guide portions 55Y to 55BK is positioned so as to be spaced upward from the respective support surfaces 43Y to 43BK.

  On the other hand, as shown in FIG. 14, the unit case 41Y to 41BK of each of the process cartridges 40Y to 40BK is provided with an engaging portion 56 made of a projecting piece on the tip side. The front end side of the process cartridge is the back side when the process cartridge is mounted in the main body of the image forming apparatus.

  When the process cartridges 40Y to 40BK are inserted into the image forming apparatus main body 1 while being guided by the guides 42Y to 42BK, the engaging portions 56 of the process cartridges are arranged in the vertical directions shown in FIGS. The guide portions 55Y to 55BK are engaged with the lower surfaces of the guide portions 55Y to 55BK, respectively. The same applies when the process cartridges 40Y to 40BK are pulled out from the image forming apparatus main body 1. As a result, when the process cartridge is attached or detached, the process cartridge can be moved upward to prevent the image carrier from coming into contact with the intermediate transfer belt, and the image carrier can be rubbed against the surface of the intermediate transfer belt. The surface is not scratched.

  As described above, the process cartridges 40Y to 40BK, which are detachably attached to the image forming apparatus main body 1, are substantially guided by the support surfaces 43Y to 43BK. The upper and lower guide portions 55Y to 55BK provided on the side of the image forming apparatus main body 1 when the process cartridges 40Y to 40BK are attached to and detached from the image forming apparatus main body 1 are formed on the side portions of the process cartridges 40Y to 40BK. An engaging portion 56 is provided to be engaged with the upper and lower guide portions 55Y to 55BK, and the process cartridges 40Y to 40BK are restricted from moving upward. ing.

  Also, as shown in FIG. 12, the length of the vertical guide portions 55Y to 55BK in the front-rear direction of the image forming apparatus main body is set to be shorter than the length of the support surfaces 43Y to 43BK, and the process cartridges 40Y to 40BK are placed in the image forming apparatus. When inserted into the main body 1 and the process cartridge is partially inserted into the main body of the image forming apparatus, the projecting piece-like engaging portion 56 of the process cartridge is pulled out of the plate-like vertical guide portions 55Y to 55BK. It is configured. In this way, when the process cartridge has been inserted to a predetermined position in the image forming apparatus main body 1, the process cartridge can move upward, so that the image carrier of the process cartridge is transferred to the intermediate transfer. It can be brought into contact with the belt. When the process cartridges 40Y to 40BK are mounted in the image forming apparatus main body 1, the vertical guide portions 55Y to 55BK are configured to restrict the upward movement of the process cartridges 40Y to 40BK halfway. .

  In addition, in the image forming apparatus of the present example, as shown in FIG. 12, the bulging portions 57Y, 57C, 57M, and 57BK that protrude upward from the support surfaces are provided on the back side of the support surfaces 43Y to 43BK. After the process cartridges 40Y to 40BK are pushed into the image forming apparatus main body 1 and the engaging portions 56 come out of the vertical guide portions 55Y to 55BK, the respective process cartridges 40Y to 40BK are moved to the respective bulging portions 57Y. The process cartridge is lifted upward and the image carrier of each process cartridge comes into contact with the surface of the intermediate transfer belt.

  The above-described vertical guide unit and the configuration related thereto can also be applied to the image forming apparatus shown in FIGS.

  Further, when each process cartridge 40Y to 40BK is pushed into the image forming apparatus main body 1 and mounted, it is necessary to position each process cartridge at a predetermined correct position.

  Therefore, in the image forming apparatus of the present example, as shown in FIGS. 12, 13, 16, and 17, positioning holes 58Y, 58B are formed in the area on the near side of a sheet material such as a sheet metal constituting the restricting portions 54Y to 54BK. 58C, 58M, and 58BK are formed. On the other hand, as shown in FIGS. 14, 16, and 17, a reference portion including a reference protrusion 59 is provided in the front side region of the unit cases 41 </ b> Y to 41 </ b> BK of the process cartridges 40 </ b> Y to 40 </ b> BK.

  When each of the process cartridges 40Y to 40BK is inserted to the innermost position in the image forming apparatus main body 1, the reference protrusion 59 formed on each of the process cartridges, as shown in FIGS. The process cartridges fall into the positioning holes 58Y to 58BK formed in the through holes 54BK by their own weights, and engage with the positioning holes 58Y to 58BK. Accordingly, the process cartridges 40Y to 40BK are positioned in the longitudinal direction L of the process cartridges 40Y to 40BK in the image forming apparatus main body. At this time, since the process cartridges 40Y to 40BK are urged from the back side of the image forming apparatus main body 1 by urging means (not shown), for example, a compression spring, the process cartridges 40Y to 40BK are positioned in the longitudinal direction L. And is locked in its positioned position. Each positioning hole 58Y to 58BK constitutes an example of a positioning portion for positioning each process cartridge 40Y to 40BK.

  As described above, the image forming apparatus of this example includes a positioning unit that positions the process cartridges 40Y to 40BK in the longitudinal direction L when the process cartridges 40Y to 40BK are mounted in the image forming apparatus main body 1. Yes.

  In other words, each of the process cartridges 40Y to 40BK has a reference portion that engages with a positioning portion provided on the image forming apparatus body 1 side when the process cartridge is mounted in the image forming apparatus body 1. The reference portion is configured to be positioned in the longitudinal direction L by engaging the positioning portion.

  Although the process cartridge can be completely positioned by the reference portion and the positioning portion described above, the process cartridge is temporarily positioned by the reference portion and the positioning portion, and similarly to the image forming apparatus of the embodiment described above, By bringing the face plate 51 shown in FIG. 10 to the closed position, the process cartridges 40Y to 40BK can be finally positioned completely.

  When the process cartridges 40Y to 40BK are taken out from the image forming apparatus main body 1, the reference protrusion 59 of each process cartridge is removed from each positioning hole 58Y to 58BK, and the positioning in the longitudinal direction L with respect to the process cartridge is released. The process cartridge may be pulled out to the front side. At that time, it is advantageous to configure so that the positioning can be released as follows.

  As shown in FIGS. 14 to 17, a handle 60 is attached to a portion of each process cartridge 40 </ b> Y to 40 </ b> BK on the front side of the unit case. The unit cases 41Y to 41BK are pivotally mounted so as to be rotatable in the direction of the arrow Z between the use position and the storage position indicated by the symbol Y. 14, FIG. 15 and FIG. 16 show the state when the handle 60 is stored in the storage position.

  When the process cartridges 40Y to 40BK are mounted and used in the image forming apparatus main body 1, the handle 60 occupies the storage position. When taking out the process cartridge from the image forming apparatus main body 1, the handle 60 is rotated to the use position X shown in FIG. Then, the cam portion 61 provided on the proximal end side of the handle 60 contacts and pressurizes the wall surfaces of the restricting portions 54Y to 54BK made of a plate material. For this reason, the process cartridges 40Y to 40BK are slightly moved in the direction away from the restricting portions by the reaction force received from the restricting portions 54Y to 54BK. As a result, the reference protrusions 59 of the process cartridges 40Y to 40BK are disengaged from the positioning holes 58Y to 58BK. Therefore, by grasping the handle 60 and pulling it to the front side, the process cartridges 40Y to 40BK can be pulled out to the front side.

  As described above, the process cartridges 40Y to 40BK have the handle 60 connected to the unit cases 41Y to 41BK so as to be rotatable between the use position and the storage position, and the handle 60 is used. When brought to the position, the handle 60 releases the positioning of the process cartridges 40Y to 40BK in the longitudinal direction L.

  The configurations of the positioning unit, the reference unit, and the handle 60 described above can also be applied to the image forming apparatus shown in FIGS.

  The image forming apparatus shown in FIGS. 11 to 17 and other parts of the process cartridge can be configured in the same manner as the image forming apparatus and process cartridge shown in FIGS. The above description is omitted.

  In the image forming apparatus described above, the toner image formed on each image carrier is configured to be transferred to a transfer material including an intermediate transfer belt. However, the toner image formed on each image carrier is The present invention can also be applied to an image forming apparatus that directly superimposes and transfers onto a recording medium. In this case, the recording medium constitutes a transfer material to which toner images of different colors formed on the respective image carriers are transferred.

It is a schematic diagram showing an example of an image forming apparatus profile processes cartridge is applied. FIG. 2 is a view for explaining an internal structure of a process cartridge in the image forming apparatus shown in FIG. 1. It is a figure for demonstrating the movement guide structure using the process cartridge shown in FIG. It is the figure which expanded and showed a part of structure shown in FIG. It is a figure for demonstrating another example of the movement guide structure shown in FIG. 1 is a cross-sectional view illustrating an example of an image forming apparatus. FIG. 2 is an enlarged cross-sectional view of a first image carrier and an image forming apparatus provided around the first image carrier. It is sectional drawing which shows the example which provided the different guide protrusion in each guide. It is a figure which shows the process cartridge which has a guide groove fitted to a guide protrusion. It is a perspective view showing a state when a face plate pivotally attached to a front side plate of the image forming apparatus main body is rotated to an open position. It is a figure which shows the other example of an image forming apparatus. FIG. 12 is a diagram showing a state when a process cartridge is taken out from the main body of the image forming apparatus shown in FIG. 11. It is the elements on larger scale of FIG. It is an external appearance perspective view of a process cartridge. FIG. 3 is a front view of the process cartridge mounted on the image forming apparatus main body. It is a perspective view of the same state as FIG. It is a perspective view explaining the state which rotates a handle.

Explanation of symbols

1,120 Image forming apparatus body 2Y, 2C, 2M, 2BK, 125 Image carrier 3 Intermediate transfer belt 9Y, 9C, 9M, 9BK, 126 Developing device 37Y, 37C, 37M, 37BK Toner bottle 40Y, 40C, 40M, 40BK Process cartridge 42Y, 42C, 42M, 42BK Guide 43Y, 43C, 43M, 43BK Support surface 51 Face plate 54Y, 54C, 54M, 54BK Restriction part 55Y, 55C, 55M, 55BK Vertical guide part 60 Handle 121 Imaging device 1000, 1001, 1000 ', 1001' guide section
L Longitudinal direction W Width direction PC3, PC4 Opposite wall surface of cartridge housing

Claims (4)

An image forming apparatus having a cartridge assembled with an image carrier on which a toner image is formed and transferring a toner image formed on the image carrier to a transfer material to obtain a recorded image. In the image forming apparatus configured to be detachable from the image forming apparatus main body in the axial direction of the image carrier,
The transfer material comprises an intermediate transfer belt with which the image carrier of each process cartridge abuts .
A guide having a flat support surface for supporting and guiding a flat lower surface portion of the cartridge case from below when the cartridge is attached to and detached from the main body of the image forming apparatus , and a support surface positioned substantially parallel to the running side of the intermediate transfer belt ; A restriction means for restricting movement of the process cartridge in a direction perpendicular to the removal direction when the process cartridge is detached;
The restricting means includes a restricting portion protruding upward with respect to the support surface,
The regulating means comprises a vertical guide portion partially bent sheet metal constituting the restricting portion projects upwardly from the bearing surface, upper and lower guide portions, the length of the detachable direction of the process cartridge is the process An image forming apparatus, wherein the image forming apparatus is set shorter than a length of the cartridge in the attaching / detaching direction , and restricts upward movement of the process cartridge when the process cartridge is attached or detached .   When the process cartridge is mounted in the main body of the image forming apparatus, the vertical guide portion is configured to regulate the upward movement of the process cartridge halfway, and a portion of the support surface on the back side in the process cartridge removal direction The image forming apparatus according to claim 1, further comprising a bulging portion protruding upward from the support surface.   2. The image forming apparatus according to claim 1, further comprising a positioning portion for positioning the process cartridge in a longitudinal direction thereof when the process cartridge is mounted in the main body of the image forming apparatus.   The process cartridge has a handle that is pivotably connected between a use position and a storage position with respect to the unit case. When the handle is brought to the use position, the process cartridge The image forming apparatus according to claim 1, wherein the positioning in the longitudinal direction is released.

Images