JP2008145793A - Process cartridge and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process cartridge which has a developer amount detecting section projecting from the frame of the process cartridge and can achieve the miniaturization of an image forming apparatus to which a plurality of process cartridges are attached, even when the developer amount detecting section exists on a surface facing an adjacent cartridge and to provide the image forming apparatus to and from which the plurality of process cartridges can be attached and detached. <P>SOLUTION: In the process cartridge 7, the developer amount detecting section 41 detecting the amount of stored developer is projected from the side surface of one side facing a first process cartridge which is adjacent to the process cartridge 7 when the process cartridge 7 is attached to and detached from an image forming apparatus main body 100A and in the side surface of the other side facing a second process cartridge which is adjacent to the process cartridge 7 when the process cartridge 7 is attached to and detached from the image forming apparatus main body 100A, a recessed portion 45 is formed to avoid interference with the projecting portion of the developer amount detecting section 41 projecting from the adjacent second process cartridge, in attachment and detachment. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a process cartridge and an image forming apparatus that mounts a plurality of process cartridges to form an image. In particular, it is suitable for application to a color image forming apparatus.

  Here, the process cartridge is a cartridge in which a charging unit, a developing unit or a cleaning unit and an electrophotographic photosensitive drum are integrally formed, and this cartridge can be attached to and detached from the main body of the image forming apparatus. The process cartridge is a cartridge in which at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive drum are integrally formed so as to be detachable from the main body of the image forming apparatus. Further, the process cartridge refers to a cartridge in which at least the developing means and the electrophotographic photosensitive drum are integrally formed so as to be detachable from the main body of the image forming apparatus.

  The image forming apparatus forms an image on a recording medium using an electrophotographic image forming system. Examples of the image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (for example, a laser beam printer, an LED printer, etc.), a facsimile apparatus, a word processor, and the like.

  Conventionally, a so-called tandem color image forming apparatus is known as an electrophotographic image forming type color image forming apparatus. In this tandem color image forming apparatus, a plurality of, for example, four process cartridges that form toner images of each color of cyan, magenta, yellow, and black are arranged along the moving direction of the intermediate transfer member or the electrostatic transfer belt. They are arranged on a substantially straight line.

  As described above, the tandem color image forming apparatus includes a plurality of image forming units arranged in parallel to form a color image or the like, and a developer that stores toner of each color included in each cartridge. The developing operation can be performed substantially simultaneously. Therefore, a color image can be formed at high speed. On the other hand, a tandem color image forming apparatus tends to have a large installation area.

  In a tandem color image forming apparatus, an apparatus (hereinafter, referred to as a “vertical tandem system”) in which an installation area is reduced by arranging a plurality of process cartridges side by side in the vertical direction is known (for example, Patent Document 1).

  However, in the case of such a vertical tandem system, the height of the apparatus inevitably tends to increase. In particular, in recent years, the demand for desktop printers used by individuals and several people has increased, and when placed on a desk, it has been required to reduce the height of the apparatus.

Therefore, in order to suppress the height of the apparatus, there is known a system in which a plurality of process units are arranged slightly obliquely (that is, the intermediate transfer member is slightly inclined) (for example, Patent Document 2). reference).
Japanese Patent Laid-Open No. 08-190245 JP 2001-356550 A

  As described above, further downsizing of the image forming apparatus is desired.

  However, in an image forming apparatus in which a plurality of process cartridges are mounted, when the process cartridge has a developer amount detection unit protruding from the process cartridge frame, and the developer amount detection unit is on a surface facing an adjacent cartridge, The following problems occur.

  That is, the interval between adjacent cartridges is widened, and the image forming apparatus main body is enlarged.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming apparatus having a plurality of process cartridges, the process cartridge having a developer amount detection unit protruding from the process cartridge frame, and the developer amount detection unit facing an adjacent cartridge. The present invention also provides a process cartridge and an image forming apparatus in which a plurality of process cartridges can be attached and detached.

The above object is achieved by the process cartridge and the image forming apparatus according to the present invention. In summary, according to one aspect of the present invention, there is provided a process cartridge including an electrophotographic photosensitive drum, and the rotation of the photosensitive drum relative to an image forming apparatus main body in which a plurality of process cartridges are arranged in parallel. In a process cartridge that can be mounted on the image forming apparatus main body by moving in two mounting directions, a first mounting direction that is an axial direction and a second mounting direction that is an image forming operation position direction of the process cartridge,
A developer amount detection unit for detecting the amount of developer accommodated protrudes from the side surface facing the first process cartridge adjacent to the image forming apparatus main body when it is attached or detached.
The other side surface facing the adjacent second process cartridge at the time of attaching / detaching to the main body of the image forming apparatus is attached to the protruding portion of the developer amount detecting portion protruding from the adjacent second process cartridge. A recess is formed to avoid interference,
A process cartridge is provided.

According to the second aspect of the present invention, there is provided an image forming apparatus in which a plurality of process cartridges each including an electrophotographic photosensitive drum are detachably arranged side by side with respect to the image forming apparatus main body. A transfer belt for transferring a toner image formed on the electrophotographic photosensitive drum directly or onto a recording medium to be carried and transported, and the plurality of process cartridges are connected to the electrophotographic photosensitive member from the transfer belt. The second mounting is performed immediately after completion of the axial movement of the electrophotographic photosensitive drum by moving the electrophotographic photosensitive drum from the position where the drum is separated to the rotation axis of the electrophotographic photosensitive drum, which is the first mounting direction. The electrophotographic photosensitive drum is in contact with the belt surface of the transfer belt for the image forming operation in the direction, and the process cartridge In mounting is completed the image forming apparatus to the image forming apparatus main body,
The process cartridge is a process cartridge configured as described above,
In the state where the adjacent first and second process cartridges are mounted on the image forming apparatus main body, the developer amount detection of the adjacent second process cartridge is detected in the concave portion of the first process cartridge. An image forming apparatus is provided in which the protruding portion of the portion is located.

  According to the present invention, in an image forming apparatus in which a plurality of process cartridges are mounted, the process cartridge includes a developer amount detection unit protruding from the process cartridge frame, and the developer amount detection unit faces the adjacent cartridge. In this case, the image forming apparatus can be further downsized.

  Hereinafter, the process cartridge and the image forming apparatus according to the present invention will be described in more detail with reference to the drawings.

Example 1
An embodiment of an image forming apparatus according to the present invention will be described. In this embodiment, the image forming apparatus is a color electrophotographic image forming apparatus.

(Overall configuration of electrophotographic image forming apparatus)
First, an overall configuration of a color electrophotographic image forming apparatus (hereinafter referred to as “image forming apparatus”) 100 of the present embodiment will be described with reference to FIG.

  The image forming apparatus 100 shown in FIG. 1 has four process cartridges 7 (7a, 7b, 7c, 7d) that are arranged side by side with respect to the horizontal direction. The process cartridge 7 (7a to 7d) is detachably attached to the attachment opening 82b (see FIG. 3).

  Each of the process cartridges 7 (7a to 7d) includes a drum-shaped electrophotographic photosensitive member (hereinafter referred to as "photosensitive drum") 1 (1a to 1d) as an image carrier. That is, the process cartridges 7 (7a to 7d) are arranged in the image forming apparatus main body 100A so as to be aligned in a direction orthogonal to the rotational axis direction of the photosensitive drum 1 (1a to 1d).

  The photosensitive drum 1 is driven to rotate clockwise in the figure by a driving member (not shown). Around the photosensitive drum 1, the following components are arranged in order according to the rotation direction.

  That is, the cleaning member 6 (6a to 6d) for removing the toner remaining on the surface of the photosensitive drum 1 after the transfer, the charging roller 2 (2a to 2d) for uniformly charging the surface of the photosensitive drum 1, and the image information. Based on this, a scanner unit 3 (3a, 3b) for irradiating a laser beam to form an electrostatic latent image on the photosensitive drum 1 is disposed.

  Further, an electrostatic latent image formed on the photosensitive drum 1 is developed around the photosensitive drum 1 using a developer (hereinafter referred to as “toner”), and a developed image (hereinafter referred to as “toner”). The developing unit 4 (4a to 4d) is referred to as an “image”.

  A transfer unit 5 is disposed around the photosensitive drum 1. The transfer unit 5 can be used in the present invention in either case of a configuration using an intermediate transfer belt or a configuration using a paper transport belt. In this embodiment, a case where an intermediate transfer belt is used will be described.

  That is, in this embodiment, the transfer unit 5 is an intermediate transfer unit 5 that collectively transfers toner images of four colors on the photosensitive drum 1. The intermediate transfer unit 5 includes an intermediate transfer belt 5a that is stretched around rollers 56, 57, and 59 and rotates in the direction of arrow A.

  Here, the photosensitive drum 1, the cleaning member 6, the charging roller 2, and the developing unit 4 are integrally formed into a cartridge to form a process cartridge 7.

  A primary transfer roller 51 (51a to 51d) is provided at a position facing the photosensitive drum 1 with the intermediate transfer belt 5a interposed therebetween.

  Further, on the right side in FIG. 1, the intermediate transfer belt 5 a is opposed to and in contact with the secondary transfer roller 52.

  In the lower part of the image forming apparatus main body 100A, a paper feed cassette 17a for storing the recording medium S as a transfer material, a paper feed roller 54 for feeding the recording medium S, and a pair of transport rollers for transporting the recording medium S are provided. 76 is provided.

(Process cartridge)
Next, the process cartridge 7 according to this embodiment will be described with reference to FIG.

  FIG. 2 is a main cross section of the process cartridge 7 containing a developer, that is, toner.

  The cartridge 7a containing yellow toner, the cartridge 7b containing magenta toner, the cartridge 7c containing cyan toner, and the cartridge 7d containing black toner have the same configuration. Therefore, in the following description, the cartridges 7a, 7b, 7c, and 7d will be collectively referred to as the cartridge 7. Similarly, the constituent members constituting the cartridge 7 will be collectively described.

  The process cartridge 7 includes a photosensitive unit 26 as a first frame including the photosensitive drum 1, the charging roller 2, and the cleaning member 6, and a developing unit 4 as a second frame having a developing member such as the developing roller 25. It is divided into.

  The photosensitive drum 1 is rotatably attached to the cleaning frame 27 of the photosensitive unit 26 via a bearing (not shown). As described above, the charging roller 2 and the cleaning member 6 are disposed on the periphery of the photosensitive drum 1. The residual toner removed from the surface of the photosensitive drum 1 by the cleaning member 6 falls into the removed toner chamber 27a. Then, by transmitting a driving force of a driving motor (not shown) to the photosensitive unit 26, the photosensitive drum 1 is rotationally driven according to an image forming operation. A charging roller bearing 28 is attached to the cleaning frame 27 so as to be movable in the direction of arrow D passing through the center of the charging roller 2 and the center of the photosensitive drum 1. The shaft 2j of the charging roller 2 is rotatably attached to the charging roller bearing 28. The charging roller bearing 28 is in a state of being pressed toward the photosensitive drum 1 by the charging roller pressing member 46.

  The developing unit 4 includes a developing roller 25 and a developing frame 31 that rotate in the direction of arrow B in contact with the photosensitive drum 1. The developing roller 25 is rotatably supported by the developing frame 31 via bearing members (not shown) attached to both sides of the developing frame 31. Further, on the circumference of the developing roller 25, a toner supply roller 34 that contacts the developing roller 25 and rotates in the direction of arrow C and a developing blade 35 for regulating the toner layer on the developing roller 25 are respectively disposed. . Further, the toner container 31a of the developing frame 31 is provided with a toner transport member 36 for stirring the stored toner and transporting the toner to the toner supply roller 34.

  The developing unit 4 is rotatably coupled to the photoreceptor unit 26 around shafts 37R and 37L that are provided in the bearing members 32R and 32L and fit into the holes 32Rb and 32Lb. At the time of image formation of the process cartridge 7, the developing unit 4 is biased by the pressure spring 38 and thus rotates around the shaft 37, and the developing roller 25 is in contact with the photosensitive drum 1.

  Further, the developing device frame 31 is provided with a toner remaining amount detection light guide 41 as a developer amount detecting unit for detecting the amount of developer contained in the developing unit 4. In such a system in which light is transmitted through the container 31a in order to detect the remaining amount of toner, light emitted from the main body outside the container 31a is a light guide 41 made of a transparent resin member such as acrylic, PS, or PC. From the incident position, the detection position in the container 31a is passed. Then, the optical path is again guided from the emission position outside the container 31a to the light receiving position of the main body. For this reason, in this system, the light guide 41 usually protrudes outside the container 31a in order to ensure the entrance and exit of light. Furthermore, it is arranged in the vicinity of the longitudinal center in order to reduce the measurement error of the remaining amount of toner due to the inclination of the main body.

(Image forming operation)
Referring to FIG. 1, the image forming operation is as follows.

  First, the photosensitive drum 1 of each cartridge 7 is rotated in accordance with the timing of image formation by a drive transmission unit provided in the image forming apparatus main body 100A. Then, the scanner unit 3 (3a, 3b) corresponding to each process cartridge 7 is driven.

  Then, as the photosensitive drum 1 rotates, the charging roller 2 also rotates. At that time, a charging bias is applied to the charging roller 2. As a result, a uniform charge is applied to the peripheral surface of the photosensitive drum 1.

  The scanner unit 3 irradiates the peripheral surface of the photosensitive drum 1 with a laser beam L according to image information. As a result, an electrostatic latent image is formed on the peripheral surface of the photosensitive drum 1.

  A developing roller 25 rotatably supported by the developing unit 4 develops the electrostatic latent image using toner and forms a toner image on the photosensitive drum 1.

  The toner image is sequentially transferred from the photosensitive drum 1 onto the intermediate transfer belt 5a by applying a positive bias to the primary transfer roller 51 (51a to 51d), and the four color toner images are overlapped. Then, it is conveyed to the secondary transfer roller 52.

  The recording medium S as a transfer material is fed to the transport roller 76 by the paper feed roller 54 of the feeding device 17 and then transported by the registration roller pair 55. Further, the intermediate transfer belt 5a and the secondary transfer roller 52 are connected to each other. It passes through the abutting part that abuts. By applying a positive bias to the secondary transfer roller 52 at the contact portion, toner images are transferred from the intermediate transfer belt 5a to the recording medium S all at once.

  Thereafter, the recording medium S is conveyed to the fixing unit 106. Then, the developer image is thermally fixed to the recording medium S in the fixing unit 106. Thereafter, the recording medium S is discharged from the discharge unit 107 to the outside of the image forming apparatus 100.

(Mechanism for mounting the process cartridge to the image forming apparatus main body)
Next, referring to FIG. 3, a mounting mechanism for mounting the process cartridge, which is a characteristic part of the present invention, to the image forming apparatus main body 100A will be described. 3 is a left side view of FIG. 1 which is a front view.

  The process cartridge 7 is mounted in the image forming operation position of the process cartridge where the photosensitive drum 1 is in contact with the intermediate transfer belt 5a and the drum axis (rotation axis) direction of the photosensitive drum 1 (that is, the first mounting direction). That is, the intermediate transfer belt 5a needs to move in two directions with respect to the belt direction (that is, the second mounting direction).

  FIG. 3A is a diagram illustrating a state before the process cartridge 7 is attached to the image forming apparatus main body 100A. In FIG. 3A, the process cartridge 7 is mounted parallel to the drum axis in the direction of arrow E (first mounting direction) from the mounting opening 82b of the front plate 82 of the image forming apparatus main body 100A.

  FIG. 3B is a view for explaining the state of the mounting operation of the process cartridge 7 to the image forming apparatus main body 100A in the drum longitudinal direction. At that time, the guided portion 27b provided integrally with the cleaning frame 27 of the process cartridge 7 is guided while being guided while being placed on the guide portion 81a of the guide member 81 provided in the image forming apparatus main body 100A. Mounted in E direction.

  FIG. 3C is a view for explaining the state of the mounting operation when the photosensitive drum 1 of the process cartridge 7 contacts the transfer belt 5a. At that time, the guided portion 27b provided integrally with the cleaning frame 27 of the process cartridge 7 is guided while being guided while being placed on the guide portion 81b of the guide member 81 provided in the image forming apparatus main body 100A. It is mounted in the F direction (second mounting direction). By this operation, the photosensitive drum 1 moves in a direction in which it is in contact with the intermediate transfer belt 5a.

  FIG. 3D is a diagram illustrating a state in which the process cartridge 7 is completely attached to the image forming apparatus main body 100A, that is, a state in which the process cartridge 7 is attached to the image forming operation position. Here, the positioning portions 27Re and 27Le provided integrally with the cleaning frame 27 come into contact with the abutting portion 82a of the front side plate 82 and the abutting portion 83a of the rear side plate 83 of the image forming apparatus main body 100A, respectively. The cartridge 7 is completely positioned on the image forming apparatus main body 100A. In this state, the photosensitive drum 1 and the transfer belt 5a also come into contact with each other.

(Image forming device miniaturized configuration (when installed))
Next, a configuration for downsizing will be described. FIG. 4A shows a cross-sectional view of the plurality of process cartridges 7 and, in this embodiment, the process cartridges 7b and 7c are mounted on the image forming apparatus.

  The adjacent portions of the process cartridges 7b and 7c that are adjacent to each other will be described. In the process cartridge 7c, a toner remaining amount detection light guide 41c protruding from the developing frame 31c is arranged at the center in the height direction of the developing unit 4c of the process cartridge 7c.

  On the other hand, the cleaning frame 27b of the photosensitive unit 26b of the process cartridge 7b is provided with a recess 45b on the surface facing the light guide 41c.

  In a virtual plane parallel to the mounting direction G (second mounting direction) of the process cartridges 7b and 7c, the light guide 41c and the recess 45b of the cleaning frame 27b are arranged to overlap each other. That is, when the process cartridge is mounted, the adjacent process cartridges 7b and 7c are mounted on the image forming apparatus main body 100A, and the protrusion of the light guide 41c of the adjacent process cartridge 7c is in the recess 45b of the process cartridge 7b. It will rush and be positioned. Thereby, when the image forming apparatus main body is mounted, it is possible to avoid interference between the adjacent process cartridges 7b and 7c caused by the light guide 41c protruding from the process cartridge 7c.

  With such a configuration, the distance in the pitch direction B between the photosensitive drums 1b and 1c can be reduced. Therefore, it is possible to reduce the size of the image forming apparatus.

  As shown in FIG. 1, the above-described configuration is adopted not only in the process cartridges 7b and 7c but also in the other adjacent process cartridges 7, that is, between the cartridges 7a and 7b and the cartridges 7c and 7d. Have achieved.

  That is, the recess 45a of the cleaning frame 27a of the process cartridge 7a adjacent to the light guide 41b of the process cartridge 7b is arranged so as to overlap. Further, as described above, the recess 45b of the cleaning frame 27b of the process cartridge 7b adjacent to the light guide 41c of the process cartridge 7c is arranged to overlap. Furthermore, the process guide 7d is disposed so that the recess 45c of the cleaning frame 27c of the process cartridge 7c adjacent to the light guide 41d of the process cartridge 7d overlaps.

  Next, in the modified embodiment shown in FIG. 4B, the position of the light guide 41 is attached toward the lower part of the developing unit 4. At this time as well, the light guide 41 and the recess 45 of the cleaning frame 27 are arranged so as to overlap with respect to the process cartridge mounting direction G, so that the image forming apparatus can be downsized in the drum pitch direction B. .

(Image forming device miniaturization configuration))
Next, a configuration for reducing the size when the process cartridge is mounted on the image forming apparatus will be described.

  4 (a) and 4 (b) are different in the arrangement of the light guide 41 and the recess 45, but the main body and the mounting configuration are the same, so the case of FIG. 4 (a). The light guide mounting position will be described.

  A mounting operation in the process cartridge 7c adjacent to the process cartridge 7b will be described.

  First, the case where the right cartridge 7c is mounted in the state where the left cartridge 7b is mounted in FIG. 4A will be described with reference to FIGS. 5A shows the mounting position of the light guide 41c of the right cartridge 7c, and FIGS. 5B and 5C show the recess 45b of the left cartridge 7b. In the present embodiment, the recess 45b is formed along the first and second regions (regions H and J) formed in the first mounting direction of the process cartridge and along the second mounting direction. It has the 3rd field (areas I and K) which connects the 2nd field.

  As described above, the mounting of the process cartridge requires two movements in the drum axis direction and the transfer belt direction.

  First, when the right cartridge 7c moves horizontally along the guide portion 81a in FIG. 3, the locus of the light guide 41c of the right cartridge 7c is the first region of the recess 45b of the cleaning frame 27b of the left cartridge 7b. The region H is advanced.

  Further, when the cartridge 7c rides on the guide portion 81b, the cartridge 7c advances through the region I which is the third region of the concave portion 45b of the photoreceptor unit 26b.

  Thus, the light guide 41c protruding from the developing frame 31c advances in the recess 45b of the cleaning frame 27b, thereby realizing the downsizing of the image forming apparatus in the pitch direction B between the drums.

  Next, the case where the left cartridge 7b is mounted while the right cartridge 7c is mounted in FIG. 4A will be described.

  First, when the left cartridge 7b moves horizontally along the guide portion 81a in FIG. 3, the region J, which is the second region of the recess 45b of the cleaning frame 27b of the left cartridge 7b, is written to the right cartridge 7c. Mount on the guide 41c.

  Further, when the left cartridge 7b rides on the guide portion 81b, the light guide 41c is mounted so that the region K, which is the third region of the recess 45b of the cleaning frame 27b, overlaps. In this manner, the process cartridge is mounted on the image forming apparatus main body 100A while the light guide 41c of the right cartridge 7c and the recess 45b of the cleaning frame 27b of the photosensitive unit 26b of the left cartridge 7b overlap with each other. The image forming apparatus can be downsized in the pitch direction B.

  Further, the case where the process cartridge 7 is attached to the image forming apparatus main body 100A has been described above. However, the light guide 41 and the recess 45 of the cleaning frame 27 overlap when the process cartridge 7 is taken out from the image forming apparatus main body 100A. However, the image forming apparatus can be downsized in the pitch direction B between the drums by following a trajectory opposite to that at the time of mounting.

Example 2
Next, another embodiment of the image forming apparatus of the present invention will be described with reference to FIG. In this embodiment, the image forming apparatus 100 is configured such that the process cartridges 7 (7a, 7b, 7c, and 7d) are vertically arranged in the image forming apparatus. The transfer unit 5 uses a transfer belt 5b that carries and conveys the recording medium S instead of the intermediate transfer belt 5a. Therefore, the toner image on the photosensitive drum 1 (1a, 1b, 1c, 1d) is directly transferred onto the recording medium S.

  The configuration and mounting mechanism of the image forming apparatus 100 and the process cartridge 7 are the same as those in the first embodiment. Therefore, members having the same configuration and function are denoted by the same reference numerals, and detailed description thereof is the same as in the first embodiment. Use the explanation.

  FIG. 6 shows the overall configuration of the image forming apparatus 100 of this embodiment. In the present embodiment, the image forming apparatus 100 includes four process cartridge 7 mounting portions (not shown) that are arranged side by side with respect to the vertical direction. The configuration of the process cartridge 7 is the same as that of the process cartridge 7 described in the first embodiment with reference to FIG.

  Even when the process cartridges 7 (7a to 7d) are provided vertically, the mounting mechanism of the process cartridge 7 has the same configuration as the mounting mechanism in the first embodiment described with reference to FIG.

  The configuration for downsizing the image forming apparatus is the same as that in the first embodiment. That is, in the virtual plane parallel to the process cartridge mounting direction G, the light guide 41 and the recess 45 of the cleaning frame 27 of the adjacent process cartridge are arranged so as to overlap each other, thereby forming an image in the drum pitch direction B. The device is downsized.

  That is, the recess 45a of the cleaning frame 27a of the process cartridge 7a adjacent to the light guide 41b of the process cartridge 7b is arranged so as to overlap. Further, the recess 45b of the cleaning frame 27b of the process cartridge 7b adjacent to the light guide 41c of the process cartridge 7c is arranged so as to overlap. Furthermore, the process guide 7d is disposed so that the recess 45c of the cleaning frame 27c of the process cartridge 7c adjacent to the light guide 41d of the process cartridge 7d overlaps.

  Further, the process cartridge is attached to and detached from the image forming apparatus while the light guide 41 and the recess 45 of the cleaning frame 27 of the photoconductor unit 26 overlap each other, thereby reducing the size of the image forming apparatus in the pitch direction B between the drums. it can.

Example 3
Next, another embodiment of the image forming apparatus of the present invention will be described with reference to FIG. In the present embodiment, the configuration and mounting mechanism of the image forming apparatus 100 and the process cartridge 7 are the same as those in the first embodiment. Therefore, members having the same configuration and function are denoted by the same reference numerals and are described in detail. Uses the description of Example 1.

  However, in the third embodiment, the developing unit 4 of the process cartridge 7 is provided with a recess 46, and the cleaning frame 27 of the photosensitive unit 26 has a light guide 42. That is, the light guide 42 is a removed toner amount detection light guide as a developer amount detection unit that detects the amount of developer stored (accommodated) in the cleaning frame 27 that functions as a removed toner storage unit.

  FIG. 7 shows the overall configuration of the image forming apparatus 100 of this embodiment. The structure of the process cartridge 7 (7a, 7b, 7c, 7d) is shown in FIG. The cleaning frame 27 of the photosensitive unit 26 is provided with a light guide (developer amount detection unit) 42 for detecting the removed toner amount stored in the cleaning frame 27 so as to protrude from the photosensitive unit 26.

  FIG. 7 is a cross-sectional view when a plurality of process cartridges are mounted on the image forming apparatus.

  According to this embodiment, the photosensitive unit 26 of the process cartridge 7 has the removed toner amount detection light guide 42 protruding from the cleaning frame 27. The developing unit 4 is provided with a recess 46 on the surface facing the light guide 42. By arranging the light guide 42 and the recess 46 so as to overlap with the mounting direction G of the process cartridge 7, the image forming apparatus can be downsized in the pitch direction B between the drums.

(Image forming device downsizing configuration)
Next, a configuration for reducing the size when the process cartridge is mounted on the image forming apparatus will be described.

  The mounting operation in the process cartridge 7c adjacent to the process cartridge 7b will be described below.

  First, the case where the left cartridge 7b is mounted while the right cartridge 7c is mounted in FIG. 7 will be described with reference to FIG.

  As described above, the mounting of the process cartridge requires two movements in the drum axis direction and the transfer belt direction.

  First, when the left cartridge 7b advances horizontally along the guide portion 81a, the light guide 42b of the left cartridge 7b advances through the recess 46c of the developing unit 4c of the right cartridge 7c. Furthermore, when the cartridge 7b rides on the guide portion 81b, the cartridge 7b advances through the recess 46c of the developing unit 4c.

  As described above, the light guide 42b protruding from the frame 27b of the photosensitive unit 26b advances through the recess 46c, thereby realizing the downsizing of the image forming apparatus in the pitch direction B between the drums.

  Next, a case where the right cartridge 7c is mounted while the left cartridge 7b is mounted in FIG. 7 will be described.

  First, when the right cartridge 7c advances horizontally along the guide portion 81a, the concave portion 46c of the developing unit 4c of the right cartridge 7c is mounted so as to overlap the light guide 42b of the left cartridge 7b. Further, when the right cartridge 7c rides on the guide portion 81b, the concave portion 46c of the developing unit 4c of the right cartridge 7c and the light guide 42b of the left cartridge 7b are mounted so as to overlap.

  As described above, the right process cartridge 7c is mounted on the image forming apparatus while the light guide 42b and the concave portion 46c of the developing unit 4c overlap with each other, so that the size of the image forming apparatus can be reduced in the pitch direction B between the drums.

  Further, the case where the process cartridge 7 is mounted on the image forming apparatus main body 100A has been described above. However, the light guide 42 and the concave portion 46 of the developing unit overlap while the process cartridge 7 is taken out from the image forming apparatus main body 100A. By following a trajectory opposite to that at the time of mounting, the image forming apparatus can be downsized in the pitch direction B between the drums.

Example 4
Next, another embodiment of the image forming apparatus of the present invention will be described with reference to FIG. In this embodiment, the image forming apparatus 100 has a configuration in which process cartridges 7 (7a, 7b, 7c, and 7d) are vertically arranged in the image forming apparatus as in the second embodiment. The transfer unit 5 uses a transfer belt 5b that carries and conveys the recording medium S instead of the intermediate transfer belt 5a. Accordingly, the toner image on the photosensitive drum is directly transferred onto the recording medium S.

  The configuration and mounting mechanism of the image forming apparatus 100 and the process cartridge 7 are the same as those in the second embodiment (and the first embodiment). Therefore, members having the same configuration and function are denoted by the same reference numerals, For the detailed description, the description of Examples 1 and 2 is used.

  However, in the fourth embodiment, the remaining toner amount detection unit (developer amount detection unit) of the process cartridge 7 is not a light guide as in the second embodiment but a piezo method that detects an output change of a piezo element (piezoelectric element). The toner remaining amount detecting piezoelectric element 43 (43a, 43b, 43c, 43d) is used.

  The configuration and mounting mechanism of the process cartridge 7 other than the image forming apparatus, the remaining toner amount detecting piezoelectric element 43, and the downsized configuration of the image forming apparatus are the same as those in the second embodiment (and the first embodiment).

  Also in this embodiment, between the adjacent process cartridges, the toner remaining amount detecting piezoelectric element 43 and the concave portion 45 of the developing unit 4 are overlapped on each other in a virtual plane parallel to the mounting direction G of the process cartridge. To place. Further, the process cartridge 7 is attached to and detached from the image forming apparatus while the toner remaining amount detecting piezoelectric element 43 and the concave portion 45 of the developing unit 4 overlap. As a result, the image forming apparatus can be downsized in the pitch direction B between the drums.

1 is an overall configuration diagram of an embodiment of an image forming apparatus according to the present invention. FIG. 7 is a cross-sectional view showing an embodiment of a process cartridge having a light guide at the center of the developing unit and a recess in the photosensitive unit. FIG. 6 is a diagram for explaining the mounting operation of the process cartridge to the apparatus main body. It is sectional drawing for demonstrating the overlap of an adjacent process cartridge. FIG. 5A illustrates the arrangement of the light guide, FIG. 5B illustrates the concave shape of the photosensitive unit, and FIG. 5C illustrates the locus of the light guide. FIG. 6 is an overall configuration diagram of another embodiment of the image forming apparatus according to the present invention, showing a state in which a process cartridge having a light guide provided in a developing unit and a recess provided in a photosensitive unit is mounted in a vertical in-line image forming apparatus . FIG. 5 is an overall configuration diagram of another embodiment of the image forming apparatus according to the present invention, showing a state where a process cartridge having a light guide in the photosensitive unit and a recess in the developing unit is mounted. FIG. 5 is a cross-sectional view illustrating an example of a process cartridge having a light guide in a photosensitive unit and a developing unit recess. FIG. 5 is an overall configuration diagram of another embodiment of the image forming apparatus according to the present invention. In the vertical in-line image forming apparatus, a developing unit is provided with a piezo-type toner remaining amount detecting means and a photosensitive unit is provided with a recess The state where is attached.

Explanation of symbols

1 (1a to 1d) Electrophotographic photosensitive drum 2 (2a to 2d) Charging roller 3 (3a, 3b) Scanner unit 4 (4a to 4d) Development unit 5 Intermediate transfer unit 5a Intermediate transfer belt 5b Transfer belt 6 (6a to 6a) 6d) Cleaning member 7 (7a to 7d) Process cartridge 25 Developing roller 26 Photosensitive unit 27 Cleaning frame 27a Removal toner chamber 27b Guided portion 27c Abutting portion 27e (27Re, 27Le) Positioning portion 31 Developing frame 41 Toner remaining Light guide for amount detection (Developer amount detection part)
42 Light guide for detecting the amount of removed toner (developer amount detector)
43 Piezoelectric element for detecting the remaining amount of toner (developer amount detector)
45 Concave part of cleaning frame 46 Concave part of development unit 81 Guide member 81a Guide part 81b Guide part 82 Front plate 82a Abutting part 82b Mounting opening 83 Rear side plate 83a Abutting part 100 Image forming apparatus 100A Image forming apparatus main body

Claims (5)

A process cartridge including an electrophotographic photosensitive drum, wherein a first mounting direction that is a rotational axis direction of the photosensitive drum and a process cartridge with respect to an image forming apparatus main body in which a plurality of process cartridges are arranged in parallel In the process cartridge that can be mounted on the image forming apparatus main body by moving in the two mounting directions of the second mounting direction that is the image forming operation position direction,
A developer amount detection unit for detecting the amount of developer accommodated protrudes from the side surface facing the first process cartridge adjacent to the image forming apparatus main body when it is attached or detached.
The other side surface facing the adjacent second process cartridge at the time of attaching / detaching to the main body of the image forming apparatus is attached to the protruding portion of the developer amount detecting portion protruding from the adjacent second process cartridge. A recess is formed to avoid interference,
A process cartridge characterized by that.   The recess is formed along the second mounting direction with the first and second regions formed in the first mounting direction of the process cartridge, and a third connecting the first and second regions. The process cartridge according to claim 1, further comprising: A developing frame having a developer containing portion for containing a developer for developing an electrostatic latent image formed on the electrophotographic photosensitive drum, and a removal removed from the electrophotographic photosensitive drum by a cleaning member A cleaning frame having a removed developer containing portion for containing the developer,
The developer amount detection unit is provided on the developing frame body to detect the amount of developer stored in the developer storage unit, and the protrusion of the developer amount detection unit protrudes from the development frame body. And
The recess is formed in the cleaning frame;
The process cartridge according to claim 1 or 2, wherein A developing frame having a developer containing portion for containing a developer for developing an electrostatic latent image formed on the electrophotographic photosensitive drum, and a removal removed from the electrophotographic photosensitive drum by a cleaning member A cleaning frame having a removed developer containing portion for containing the developer,
The developer amount detection unit is provided in the cleaning frame body to detect the developer amount stored in the removed developer storage unit, and the protruding portion of the developer amount detection unit is separated from the cleaning frame body. Protruding,
The recess is formed in the developing frame;
The process cartridge according to claim 1 or 2, wherein An image forming apparatus in which a plurality of process cartridges each including an electrophotographic photosensitive drum is detachably arranged in parallel with the image forming apparatus main body, and is formed on the electrophotographic photosensitive drum provided in each process cartridge. A plurality of process cartridges are mounted first from a position where the electrophotographic photosensitive drum is separated from the transfer belt. In the direction of the rotation axis of the electrophotographic photosensitive drum, and the transfer for the image forming operation in the second mounting direction immediately before completion of the axial movement of the electrophotographic photosensitive drum. The electrophotographic photosensitive drum moves in a direction in contact with the belt surface of the belt, and the mounting of the process cartridge to the image forming apparatus main body is completed. In the image forming apparatus,
The process cartridge is the process cartridge according to any one of claims 1 to 4,
In the state where the adjacent first and second process cartridges are mounted on the image forming apparatus main body, the developer amount detection of the adjacent second process cartridge is detected in the concave portion of the first process cartridge. An image forming apparatus, wherein a protruding portion of the portion is located.

Images