JP5853680B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus employing an electrophotographic system.

  2. Description of the Related Art Conventionally, an electrophotographic image forming apparatus that forms an image with a developer such as toner is known. In such an image forming apparatus, waste toner is generated in the image forming process.

  Therefore, various methods for treating such waste toner have been studied. For example, a method is known in which a new toner box that stores unused toner and a waste toner box that stores waste toner are integrally held in a cartridge that is detachable from the image forming apparatus.

  According to such a method, the user can replace the waste toner box without being aware of waste toner processing. In addition, since the replacement frequency of the waste toner box becomes the same as the replacement frequency of the new toner box, the capacity of the waste toner box may be configured to a fixed ratio with respect to the capacity of the new toner box. it can. Therefore, it is possible to reduce the size of the waste toner box, thereby reducing the size of the image forming apparatus.

  However, the cartridge includes a developing device integrally including a developing roller and a new toner box, and a waste toner box. To attach and detach the cartridge to and from the image forming apparatus, the developing roller is attached to the image forming apparatus. It is necessary to hold the photosensitive drum to be relatively movable.

  On the other hand, the waste toner box is connected to a means for collecting waste toner from a cleaning object, such as a photosensitive drum or a belt, and therefore needs to be held so as not to move relative to the cleaning object.

  Therefore, in order to hold the developing roller so as to be movable relative to the photosensitive drum, the developing device needs to be configured to be movable relative to the waste toner box.

  In the image forming apparatus, in consideration of the life of consumables such as a new toner box, a developing device including a developing roller, and a photosensitive drum, a consumable product having a short life, such as a new toner box or a developing device (cartridge), and It is desirable in terms of environment and running cost reduction that consumables having a relatively long life such as drums can be independently replaced.

  As an image forming apparatus that satisfies the above several requirements, an image forming apparatus including an apparatus main body and an imaging cartridge attached to the apparatus main body has been proposed (for example, see Patent Document 1). The imaging cartridge includes a process cartridge including a photoconductor and a developing device, and a toner box unit attached to the process cartridge.

  In this image forming apparatus, the toner box unit includes a new toner box that stores unused toner to be supplied to the developing device and includes a developing side rotation shaft, and a waste toner box that stores waste toner. A developing device is adjacently disposed on one side of the first toner box, and a first pressing mechanism provided in the apparatus main body is disposed on the other side of the new toner box.

  In such an image forming apparatus, the first pressing mechanism presses the lower part of the other side of the new toner box upward. Then, the new toner box is rotated about the developing side rotation shaft, and presses the developing device toward the photosensitive member. As a result, the developing roller is pressed in a direction approaching the photoconductor.

JP 2009-48138 A

  However, in the image forming apparatus described in Patent Document 1, since the upward pressing force of the first pressing mechanism is transmitted to the developing roller through the rotation of the new toner box, the developing roller is directed toward the photosensitive member. In some cases, the pressing cannot be performed stably, and the positioning accuracy between the developing roller and the photosensitive drum cannot be sufficiently achieved.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus capable of improving the relative positioning accuracy between a developing roller and a photosensitive drum while accommodating a waste developer accommodating portion in a compact manner.

(1) In order to achieve the above object, an image forming apparatus according to the present invention includes an apparatus main body, a photosensitive drum rotatably supported by the apparatus main body, and a photosensitive drum supported by the apparatus main body. On the other hand, the developing cartridge is detachably mounted.

  The developing cartridge is disposed opposite to the photosensitive drum in a state of being mounted on the apparatus main body, and includes a developing roller for supplying the developer to the photosensitive drum, and a developer accommodating portion for accommodating the developer. And a housing for accommodating a waste developer for housing the developer, and housing the developing device in a relatively movable manner.

  The casing is disposed on the opposite side of the photosensitive drum with respect to the developing roller.

  A biasing member that biases the developing roller toward the photosensitive drum is provided between the housing and the developing device.

  According to such a configuration, since the developing cartridge can be attached to and detached from the apparatus main body in a state where the photosensitive drum is supported by the apparatus main body, a developing cartridge (developing device) having a shorter life than the photosensitive drum is provided. It can be replaced independently of the photosensitive drum.

  In addition, the housing that houses the developing device is disposed on the opposite side of the photosensitive drum with respect to the developing roller, and the biasing member is provided between the housing and the developing device. The direction in which the developing roller is urged toward the photosensitive drum is substantially parallel to the direction in which the developing roller and the photosensitive drum face each other.

  Therefore, the urging force of the urging member acts along the opposing direction of the developing roller and the photosensitive drum, so that the developing roller can be stably pressed toward the photosensitive drum. The relative positioning accuracy can be improved.

Therefore, the relative positioning accuracy between the developing roller and the photosensitive drum can be improved while the waste developer accommodating portion can be accommodated in a compact manner.
(2) A drum collection unit including a drum collection unit that removes and collects the waste developer from the surface of the photosensitive drum, and a drum storage unit that stores the waste developer collected by the drum collection unit; A drum transport member for transporting the waste developer from the drum storage section to the waste developer storage section, having one end connected to the waste developer storage section and the other end connected to the drum storage section. Also good.

  According to such a configuration, the waste developer is removed from the surface of the photosensitive drum by the drum collection unit, and once collected in the drum storage unit, the waste developer is stored in the waste developer storage unit. Can do.

In this case, the waste developer container is configured so as not to move relative to the photosensitive drum, but the developing device including the developing roller is relatively movable with respect to the housing including the waste developer container. Therefore, it is possible to collect and store the waste developer on the surface of the photosensitive drum while improving the relative positioning accuracy between the developing roller and the photosensitive drum.
(3) One end of the drum transport member is connected to one end in the axial direction of the photosensitive drum in the waste developer accommodating portion, and the other end is connected to one end in the axial direction in the drum storage portion. May be.

According to such a configuration, the waste developer collected by the drum collection unit is conveyed from one side in the axial direction of the photosensitive drum to the waste developer storage unit while ensuring the efficient arrangement of the drum conveyance member. Can do.
(4) Further, the drum conveying member is configured such that at least one of the one end portion and the other end portion can be disconnected from at least one of the waste developer storage portion and the drum storage portion. You may have. In this case, the drum separation unit includes a drum opening and a drum shutter that can open and close the drum opening, and the drum opening is at least one of the drum separation unit, the waste developer storage unit, and the drum storage unit. In the state where the connection with is released, the drum shutter is closed.

  According to such a configuration, it is possible to separate the drum recovery unit disposed adjacent to the photosensitive drum and the waste developer storage unit provided in the housing. Therefore, the developing cartridge can be replaced independently of the drum collection unit.

  In this case, in a state where the connection between the drum separation unit and at least one of the waste developer storage unit and the drum storage unit is released, the waste developer leaks from the drum opening, and the apparatus main body may be soiled. is there.

In this respect, the drum opening is closed by the drum shutter in a state where the connection between the drum separation unit and at least one of the waste developer storage unit and the drum storage unit is released. The leakage of the agent can be suppressed.
(5) Also, an endless belt disposed opposite to the photosensitive drum, a belt collecting unit that removes and collects the waste developer from the belt, and a waste developer collected by the belt collecting unit. A belt collection unit including a belt storage unit, one end of which is connected to the waste developer storage unit, the other end is connected to the belt storage unit, and transports the waste developer from the belt storage unit to the waste developer storage unit. And a belt conveying member.

  According to such a configuration, the waste developer can be removed from the belt by the belt recovery unit, and once recovered in the belt storage unit, the waste developer can be stored in the waste developer storage unit. .

In this case, the waste developer accommodating portion is configured so as not to move relative to the endless belt, but the developing device including the developing roller is relatively movable relative to the housing including the waste developer accommodating portion. Therefore, the waste developer on the belt can be collected and stored while improving the relative positioning accuracy between the developing roller and the photosensitive drum.
(6) Further, the belt conveying member is configured such that at least one of the one end portion and the other end portion can be disconnected from at least one of the waste developer storage portion and the belt storage portion. You may have. In this case, the belt separation unit includes a belt opening and a belt shutter capable of opening and closing the belt opening, and the belt opening is at least one of the belt separation unit, the waste developer storage unit, and the belt storage unit. Is closed by the belt shutter.

  According to such a configuration, the belt collecting unit disposed adjacent to the belt and the waste developer accommodating portion provided in the housing can be separated. Therefore, the developing cartridge can be replaced independently of the belt collecting unit.

  In this case, in a state where the connection between the belt separation unit and at least one of the waste developer storage unit and the belt storage unit is released, the waste developer may leak from the belt opening and may contaminate the apparatus main body. is there.

In this respect, the belt opening is closed by the belt shutter in a state where the connection between the belt separation unit and at least one of the waste developer storage unit and the belt storage unit is released. The leakage of the agent can be suppressed.
(7) Also, an endless belt disposed opposite to the photosensitive drum, a belt collecting unit that removes and collects the waste developer from the belt, and a waste developer collected by the belt collecting unit. A belt collection unit including a belt storage unit, one end of which is connected to the waste developer storage unit, the other end is connected to the belt storage unit, and transports the waste developer from the belt storage unit to the waste developer storage unit. And a belt conveying member. In this case, the belt conveying member has one end connected to the other end in the axial direction of the photosensitive drum in the waste developer accommodating portion and the other end connected to the other end in the axial direction in the belt storing portion. Yes.

  According to such a configuration, the waste developer can be removed from the belt by the belt recovery unit, and once recovered in the belt storage unit, the waste developer can be stored in the waste developer storage unit. .

  In this case, the waste developer accommodating portion is configured so as not to move relative to the endless belt, but the developing device including the developing roller is relatively movable relative to the housing including the waste developer accommodating portion. Therefore, the waste developer on the belt can be collected and stored while improving the relative positioning accuracy between the developing roller and the photosensitive drum.

  In the apparatus main body, the drum conveying member is disposed on one side in the axial direction of the photosensitive drum with respect to the waste developer accommodating portion, and the belt conveying member is disposed on the photosensitive drum axis with respect to the waste developer accommodating portion. It is arranged on the other side in the direction.

  The waste developer recovered by the drum recovery unit can be transported from one side in the axial direction of the photosensitive drum to the waste developer accommodating portion, and the waste developer recovered by the belt recovery unit can be transported to the photosensitive drum axis. From the other side in the direction, it can be transported to the waste developer container.

  Therefore, an efficient arrangement of the drum conveying member and the belt conveying member can be ensured, and the waste developer recovered from the belt and the waste developer recovered from the surface of the photosensitive drum can be used as a common waste developer. It can be accommodated in the accommodating part.

As a result, the waste developer accommodating portion can be accommodated in a compact manner while ensuring efficient arrangement of the drum conveying member and the belt conveying member.
(8) Further, the housing may include a grip portion for attaching / detaching the developing cartridge to / from the apparatus main body.

According to such a configuration, the gripping portion can be gripped when the developing cartridge is attached to and detached from the apparatus main body, so that a smooth attaching and detaching operation of the developing cartridge to the apparatus main body can be ensured.
(9) Further, a plurality of photosensitive drums may be provided corresponding to a plurality of colors, and the photosensitive drums may be arranged in parallel at intervals in a direction orthogonal to the axial direction of the photosensitive drum.

  In this case, a plurality of developing cartridges are provided corresponding to each of the plurality of photosensitive drums, and an endless belt disposed opposite to the plurality of photosensitive drums is provided above the plurality of photosensitive drums in the apparatus main body. It is done.

  The direction in which the developing cartridge is attached to and detached from the apparatus main body is the same as the axial direction of the photosensitive drum.

According to such a configuration, a full-color image is formed by accommodating the developer corresponding to each of a plurality of colors (for example, yellow, magenta, cyan, and black) in the developer accommodating portions of the plurality of developing devices. can do.
(10) The apparatus main body may be provided with a holding member that fixes the housing to the apparatus main body in a state where the developing cartridge is mounted on the apparatus main body.

  According to such a configuration, since the housing is fixed to the apparatus main body by the holding member, the relative positional relationship between the urging member and the photosensitive drum can be accurately maintained.

  Therefore, the urging member can reliably urge the developing roller toward the photosensitive drum.

As a result, it is possible to further improve the relative positioning accuracy between the developing roller and the photosensitive drum.
(11) Moreover, the holding member may be arrange | positioned with respect to the housing | casing on the opposite side of the urging | biasing member.

  According to such a structure, the reaction which arises in the housing | casing by the urging | biasing force by an urging | biasing member can be firmly received by the holding member arrange | positioned on the opposite side of an urging | biasing member.

Thus, the developing roller can be firmly urged against the photosensitive drum while the housing is securely fixed to the apparatus main body. Therefore, the relative positioning accuracy between the developing roller and the photosensitive drum can be further improved.
(12) The holding member may be configured to support the housing from the lower side, and guide the attachment and detachment of the developing cartridge with respect to the apparatus main body.

  According to such a configuration, since the holding member supports the housing from the lower side, the developing roller can be reliably urged toward the photosensitive drum.

  Further, since the holding member guides the attachment / detachment of the developing cartridge during the attaching / detaching operation of the developing cartridge with respect to the apparatus main body, a stable attaching / detaching operation of the developing cartridge can be secured. Therefore, the development roller and the development device can be prevented from coming into contact with the photosensitive drum, so that the photosensitive drum can be prevented from being damaged.

  In the image forming apparatus of the present invention, it is possible to improve the relative positioning accuracy between the developing roller and the photosensitive drum while accommodating the waste developer accommodating portion in a compact manner.

1 is a cross-sectional view illustrating a color printer as an embodiment of an image forming apparatus of the present invention. It is AA sectional drawing of the color printer shown in FIG. FIG. 2 is a cross-sectional view showing a developing cartridge and a photosensitive drum shown in FIG. 1. 1A is a cross-sectional view of the drum unit, and FIG. 1B is a front view of the drum unit. FIG. 4B is a cross-sectional view of the drum unit shown in FIG. 4A, in which FIG. 4A shows a state in which the drum unit-side shutter is disposed at the closed position, and FIG. Shows the state of placement. 1 shows a state in which the developing cartridge shown in FIG. 1 is pulled out from the main casing. FIG. 2 is a right side view of the developing cartridge shown in FIG. 1, (a) shows a right side view of the black developing cartridge, (b) shows a right side view of the black developing cartridge in a state where the developing device is removed, and (c) ) Shows a right side view of other developing cartridges (yellow developing cartridge, magenta developing cartridge, and cyan developing cartridge) in a state where the developing device is removed. FIG. 2 is a rear view of the developing cartridge shown in FIG. 1, where (a) shows a rear view of the black developing cartridge, and (b) shows other developing cartridges (yellow developing cartridge, magenta developing cartridge, and cyan developing cartridge). A rear view is shown.

1. Overall Configuration of Color Printer As shown in FIG. 1, a color printer 1 as an example of an image forming apparatus is a horizontal type intermediate transfer type color printer.

  The color printer 1 is a multi-function machine that is integrally provided with a main body casing 2 as an example of an apparatus main body and a flat bed scanner 3 that is provided on the upper side of the main body casing 2 and reads image information of a document.

In the main body casing 2, the color printer 1 includes a paper feeding unit 4 for feeding paper P and an image forming unit 5 for forming an image on the fed paper P.
(1) Main Body Casing As shown in FIGS. 1 and 2, the main body casing 2 is formed in a box shape that accommodates the paper feeding unit 4 and the image forming unit 5. A main body opening 8 is formed on one side wall of the main body casing 2, and the front cover 6 closes the main body opening 8 with its lower end as a fulcrum (see FIG. 2), and the main body opening. 8 is provided to be swingable (movable) at an open position (see FIG. 6) where 8 is opened.

  In the following description, the side on which the front cover 6 is provided (the left side in FIG. 2) is the front side, and the opposite side (the right side in FIG. 2) is the rear side. In addition, when the color printer 1 is viewed from the front side, the left and right reference is used.

That is, in FIG. 1, the left side of the drawing is the left side, and the right side of the drawing is the right side. Further, the front side of the page is the front side, and the back side of the page is the rear side.
(2) Paper Feed Unit The paper feed unit 4 includes a paper feed tray 7 that stores the paper P. The paper feed tray 7 is detachably attached to the bottom of the main casing 2.

The paper P stored in the paper feed tray 7 is sent between the paper feed roller 10 and the paper feed pad 11 by the rotation of the pickup roller 9, and is fed one by one by the rotation of the paper feed roller 10. Thereafter, the sheet P is fed toward the upper registration rollers 13 so as to sequentially pass between the sheet feeding roller 10 and each pinch roller 12 by the rotation of the sheet feeding roller 10. With the rotation of the registration roller 13, the image is supplied to the image forming unit 5 (between an intermediate transfer belt 38 (described later) and a secondary transfer roller 35 (described later)) at a predetermined timing.
(3) Image Forming Unit The image forming unit 5 is disposed on the upper side of the paper feeding unit 4 and includes a process unit 14, a transfer unit 18, and a fixing unit 19.
(3-1) Process Unit The process unit 14 is disposed on the upper side of the paper feed tray 7 and includes a drum unit 15, a developing cartridge 16, and a plurality (four) of LED units 17.
(3-1-1) Drum Unit The drum unit 15 is disposed at the upper end of the process unit 14, and integrally holds a photosensitive drum 21, a charging roller 22, and a drum cleaner 23 as an example of a drum recovery unit. doing.

  A plurality (four) of photosensitive drums 21 are provided corresponding to a plurality of colors (black, yellow, magenta, cyan), and are arranged in parallel at intervals in the left-right direction.

  The charging roller 22 is provided corresponding to each of the four photosensitive drums 21 and is disposed on the lower right side of the corresponding photosensitive drum 21 so as to face and contact the photosensitive drum 21.

The drum cleaner 23 is provided corresponding to each of the four photosensitive drums 21 and is disposed on the right side of the corresponding photosensitive drum 21.
(3-1-2) Developing Cartridge A plurality (four) of developing cartridges 16 are provided corresponding to each of the plural (four) photosensitive drums, and attached to the main body casing 2 so as to be drawable in the front-rear direction. Has been.

  Each of the plurality of developing cartridges 16 is arranged below the corresponding photosensitive drum 21 and is arranged in parallel at intervals in the left-right direction.

  Specifically, a black developing cartridge 16K, a yellow developing cartridge 16Y, a magenta developing cartridge 16M, and a cyan developing cartridge 16C are sequentially arranged from the left side to the right side.

  The developing cartridge 16 includes a developing device 24 and a cartridge frame 25 as an example of a housing, which will be described in detail later.

  The developing device 24 is accommodated in a cartridge frame 25 and includes a developing roller 26.

  The developing roller 26 is rotatably supported at the upper end of the developing device 24 so as to be exposed from the upper side (upper right side), and is in contact with the photosensitive drum 21 from the lower left side.

The developing device 24 includes a supply roller 27 that supplies toner to the developing roller 26 and a layer thickness regulating blade 28 that regulates the thickness of the toner supplied to the developing roller 26. Further, the developing unit 24 stores toner as an example of a developer corresponding to each color (black, yellow, magenta, cyan) below the supply roller 27, as an example of a developer storage unit. 29.
(3-1-3) LED Unit Each of the plurality of LED units 17 is supported by the main casing 2 so as to face the corresponding photosensitive drum 21 from below. The LED unit 17 exposes the surface of the corresponding photosensitive drum 21 based on predetermined image data.
(3-2) Transfer Unit The transfer unit 18 is disposed above the process unit 14 and includes a belt unit 34 and a secondary transfer roller 35.

  The belt unit 34 is disposed along the left-right direction so as to face each of the four photosensitive drums 21 from above.

  The belt unit 34 includes a driving roller 36, a driven roller 37, an intermediate transfer belt 38 as an example of an endless belt, a plurality (four) of primary transfer rollers 39, and a belt cleaner 40 as an example of a belt recovery unit. I have.

  The driving roller 36 and the driven roller 37 are arranged to face each other with a space in the left-right direction.

  The intermediate transfer belt 38 is disposed above the photosensitive drum 21 so that the lower portion thereof is opposed to and contacted with each of the four photosensitive drums 21, and is wound around the driving roller 36 and the driven roller 37. . In addition, the intermediate transfer belt 38 is rotated in such a way that the lower portion in contact with the photosensitive drum 21 moves from the left side to the right side by the driving of the driving roller 36 and the driven roller 37.

  Each of the plurality of primary transfer rollers 39 is provided to face the corresponding photosensitive drum 21 with the lower portion of the intermediate transfer belt 38 interposed therebetween.

  The belt cleaner 40 is disposed above the left end of the intermediate transfer belt 38, and includes a belt cleaning roller 72 and a counter roller 73, as will be described in detail later.

  The belt cleaning roller 72 is provided on the upper side of the intermediate transfer belt 38 so as to face the opposing roller 73 in the vertical direction with the intermediate transfer belt 38 interposed therebetween.

The secondary transfer roller 35 is provided on the right side of the belt unit 34 so as to face the driving roller 36 with the intermediate transfer belt 38 interposed therebetween.
(3-3) Fixing Unit The fixing unit 19 includes a heating roller 41 and a pressure roller 42 that is in pressure contact with the heating roller 41 from the upper right side. .
(3-4) Image Forming Operation (3-4-1) Developing Operation The toner in the developing device 24 is supplied to the supply roller 27 and further supplied to the developing roller 26.

  The toner supplied to the developing roller 26 is regulated by the layer thickness regulating blade 28 as the developing roller 26 rotates, and is carried on the surface of the developing roller 26 as a thin layer having a constant thickness.

  On the other hand, the surface of the photosensitive drum 21 is uniformly positively charged by the charging roller 22 as the photosensitive drum 21 rotates, and then exposed by the LED unit 17. As a result, an electrostatic latent image corresponding to the image to be formed on the paper P is formed on the surface of the photosensitive drum 21.

When the photosensitive drum 21 further rotates, the toner carried on the surface of the developing roller 26 is supplied to the electrostatic latent image formed on the surface of the photosensitive drum 21. As a result, the electrostatic latent image on the photosensitive drum 21 is visualized, and a toner image by reversal development is carried on the surface of the photosensitive drum 21.
(3-4-2) Transfer / Fixing Operation The toner image carried on the surface of the photosensitive drum 21 is primarily transferred sequentially to the lower portion of the intermediate transfer belt 38 that is moved from the left side to the right side. As a result, a color image is formed on the intermediate transfer belt 38.

  The color image formed on the intermediate transfer belt 38 is secondarily transferred onto the paper P supplied from the paper supply unit 4 while the intermediate transfer belt 38 passes through a position facing the secondary transfer roller 35.

The color image transferred onto the paper P is heat-fixed on the paper P in the fixing unit 19 by being heated and pressed while the paper P passes between the heating roller 41 and the pressure roller 42. Is done.
(4) Paper Discharge The paper P on which the toner image has been fixed in the fixing unit 19 is discharged by a paper discharge roller 44 onto a paper discharge tray 45 formed on the upper surface of the main casing 2.
(5) Flatbed Scanner The flatbed scanner 3 is provided above the paper discharge tray 45. In the flatbed scanner 3, after the original is placed between the presser cover 47 and the glass surface 48, the CCD sensor 49 slides to read the image information of the original.

Then, based on the read image information of the document, the image forming unit 5 can form an image on the paper P as described above.
2. Details of Main Body Casing As shown in FIG. 2, the main body casing 2 includes an outer casing 80 that forms the outer shape of the color printer 1 and an inner casing 81 that is provided inside the outer casing 80.

  The outer casing 80 is formed in a substantially box shape that is substantially rectangular in a side view, and includes a front cover 6 at the front end.

  The inner casing 81 is formed in a substantially box shape that is substantially rectangular in side view. The inner casing 81 has a vertical length and a horizontal length that can accommodate the paper feed unit 4 (see FIG. 1) and the image forming unit 5, and is spaced apart from the outer casing 80 on the rear side. The outer casing 80 is housed.

  Further, the inner space of the inner casing 81 is partitioned by a partition wall 111.

  The partition wall 111 is formed in a substantially flat plate shape and is provided between the paper feed tray 7 and the developing cartridge 16 in the vertical direction. The inner space of the inner casing 81 is divided into the upper cartridge housing space 115 and the lower paper feed tray. The housing space 116 is partitioned.

  A holding member 20 is provided on the upper surface of the partition wall 111.

  As shown in FIGS. 1 and 2, four holding members 20 are provided so as to correspond to the four developing cartridges.

  As shown in FIG. 2, the holding member 20 is formed in a substantially U shape in a front view and a substantially tray shape extending in the front-rear direction, and the upper, front, and rear are open. The holding member 20 is formed so that the inner surface thereof conforms to the outer shape of the lower end portion of the cartridge frame 25 (described later), and the inner dimension (the length in the left-right direction and the length in the front-rear direction) is It is formed in substantially the same length as the dimension (length in the left-right direction and length in the front-rear direction).

Specifically, the holding member 20 has a left wall whose vertical length is longer than the vertical length of the right wall, and the inner side surface of the connecting portion between the left wall and the lower wall is a waste toner container. It is formed in a substantially arc shape in front view along the outer shape of the lower end portion of 31.
3. Details of Drum Unit (1) Drum Frame The drum unit 15 includes a pair of drum frames 51 that are arranged to face each other with a gap in the front-rear direction.

  As shown in FIG. 4, the drum frame 51 is formed in a substantially flat plate shape that is long in the left-right direction, and a cartridge groove 52 is formed in a lower portion thereof.

  The cartridge groove 52 is formed by cutting out a portion that overlaps the upper end of the developing device 24 of the developing cartridge 16 when projected in the front-rear direction.

  Specifically, the cartridge groove 52 corresponding to the black developing cartridge 16K extends from the center in the vertical direction at the left end edge of the drum frame 51 to the right and then inclines downward toward the right. It is missing and formed.

  Further, the cartridge grooves 52 corresponding to the other developing cartridges 16Y, 16M, and 16C (the yellow developing cartridge 16Y, the magenta developing cartridge 16M, and the cyan developing cartridge 16C) are notched upward from the lower end edge of the drum frame 51. Further, it is formed in a substantially U shape that is open downward.

  Of the pair of drum frames 51, the front drum frame 51 includes a plurality of (four) insertion ports 53 in the left-right direction so as to correspond to a plurality of drum unit-side receiving cylinders 56 (described later). It is formed at intervals.

  The insertion port 53 is formed in a portion that overlaps a drum unit-side receiving cylinder 56 (described later) when projected in the front-rear direction, and is formed in a substantially circular shape in front view that penetrates the drum frame 51 in the front-rear direction. The hole diameter of the insertion port 53 is slightly larger than the outer diameter of the pipe-side shutter 101 (described later).

  Further, between the pair of drum frames 51, the photosensitive drum 21, the charging roller 22, and the drum cleaner 23 are supported.

  As shown in FIG. 5, the photosensitive drum 21 is formed in a substantially cylindrical shape extending in the front-rear direction, and both front and rear ends thereof are rotatably supported by the drum frame 51.

The charging roller 22 is formed in a substantially cylindrical shape extending in the front-rear direction, and both front and rear ends thereof are rotatably supported by a drum frame 51 (described later).
(2) Drum cleaner As shown in FIG. 4, the drum cleaner 23 includes a drum storage portion 54 and a drum scraping blade 55 as an example of a drum recovery portion.

  As shown in FIGS. 4 and 5, the drum storage portion 54 is formed in a substantially rectangular shape that is long in the vertical direction when viewed from the front, and extends in the front-rear direction. In addition, the lower wall of the drum storage portion 54 is formed in a substantially semicircular arc shape in front view that bulges downward along a rotation locus of a first auger screw 58 (described later).

  In the drum storage portion 54, an opening 57 is formed in the left wall (see FIG. 4), and a drum waste toner discharge port 62 is formed in the lower wall (see FIG. 5).

  As shown in FIG. 4, the opening 57 is formed through the left wall of the drum storage portion 54 in the left-right direction.

  As shown in FIG. 5, the drum waste toner discharge port 62 extends in the vertical direction so that the drum storage portion 54 and the drum unit side receiving cylinder 56 (described later) communicate with each other at the front end portion of the lower wall of the drum storage portion 54. It is formed through.

  A first auger screw 58 is provided in the drum storage portion 54.

  The 1st auger screw 58 is formed so that it may extend in the front-back direction, and is arrange | positioned along the lower wall of the drum storage part 54 (refer FIG. 4). The first auger screw 58 is rotatably supported on the front wall of the drum storage portion 54 at the front end portion thereof, and is rotatably supported on the rear wall of the drum storage portion 54 at the rear end portion thereof.

  The drum storage portion 54 is integrally provided with a front side fixing portion 59, a rear side fixing portion 60, and a drum unit side receiving cylinder 56.

  The front fixing portion 59 is formed in a substantially box shape having a substantially rectangular shape when viewed from the front, and is provided on the front wall of the drum storage portion 54. The front-side fixing portion 59 has a vertical length that is shorter than the vertical length of the drum storage portion 54.

  The rear fixing portion 60 is formed in a substantially box shape having a substantially rectangular shape when viewed from the front, and is provided on the rear wall of the drum storage portion 54. The vertical length of the rear side fixing portion 60 is formed to be approximately the same as the vertical length of the drum storage portion 54.

  The drum unit-side receiving cylinder 56 is formed in a substantially cylindrical shape extending in the front-rear direction and closed at the rear end portion, and is continuous with the front end portion of the lower wall in the drum storage portion 54 at the upper portion thereof. In addition, the inner diameter of the drum unit-side receiving cylinder 56 is formed to be approximately the same as the outer diameter of the drum-side insertion portion 99 (described later).

  The drum unit-side receiving cylinder 56 includes a drum unit-side shutter 63.

  The drum unit side shutter 63 is formed in a substantially cylindrical shape whose front end is closed, and is accommodated in the drum unit side receiving cylinder 56. The outer diameter of the drum unit side shutter 63 is formed to be substantially the same as the inner diameter of the drum unit side receiving cylinder 56. The drum unit side shutter 63 is disposed at the rear end of the drum unit side receiving cylinder 56 so as to open the drum waste toner discharge port 62 in the drum unit side receiving cylinder 56 (see FIG. 5B). And a closed position (see FIG. 5A) disposed at the front end of the drum unit side receiving cylinder 56 so as to close the drum waste toner discharge port 62.

  A compression spring 64 is interposed between the rear wall of the drum unit-side receiving cylinder 56 and the front wall of the drum unit-side shutter 63, and the drum unit-side shutter 63 is always directed forward by the compression spring 64. And is placed in the closed position.

  As shown in FIG. 4, the drum scraping blade 55 is formed in a substantially flat plate shape extending in the vertical direction, and its lower end (free end) is contacted from the right side with the upper end (free end). (Base end portion) is fixed to the left peripheral portion of the opening 57 in the left wall of the drum storage portion 54.

In the drum cleaner 23, as shown in FIG. 5, the front end portion of the front side fixing portion 59 is fixed to the front drum frame 51, and the rear end portion of the rear side fixing portion 60 is fixed to the rear drum frame 51. Thus, the drum frame 51 is held.
3. Details of Belt Unit (1) Belt Cleaner The belt cleaner 40 includes a belt cleaner frame 50 as shown in FIG.

  The belt cleaner frame 50 is formed in a substantially U shape in a side view opened upward, and is disposed between a pair of side walls 66 opposed to each other with a space in the front-rear direction and a lower end portion of the pair of side walls 66. And a covering wall 67 for erected.

  As shown in FIG. 1, the side wall 66 is formed in a substantially flat plate shape that is long in the left-right direction.

  Between the pair of side walls 66, a belt recovery unit 65 and a belt storage unit 68 are held.

  The belt collection unit 65 includes a belt cleaning roller 72 and a relay roller 74.

  The belt cleaning roller 72 is formed in a substantially cylindrical shape extending in the front-rear direction, and both front and rear ends thereof are rotatably supported by a pair of side walls 66, respectively. The covering wall 67 is notched so as to expose the lower portion of the belt cleaning roller 72, and the belt cleaning roller 72 is opposed to the opposing roller 73 in the vertical direction with the intermediate transfer belt 38 interposed therebetween. Is arranged.

  The relay roller 74 is disposed on the left side of the belt cleaning roller 72 so as to contact the belt cleaning roller 72 from the left side. The relay roller 74 is formed in a substantially cylindrical shape extending in the front-rear direction, and both front and rear ends thereof are rotatably supported by a pair of side walls 66.

  The belt storage portion 68 extends in the front-rear direction, and is formed in a substantially box shape whose front and rear end portions are each closed by a pair of side walls 66.

  In addition, an opening 69 is formed through the belt storage portion 68 in the left-right direction at the lower portion of the right wall.

  A second auger screw 71 is provided in the belt storage unit 68.

  As shown in FIG. 6, the second auger screw 71 is formed so as to extend in the front-rear direction, and a front end portion thereof is rotatably supported by the front side wall 66, and a rear end portion thereof is supported by the rear side wall 66. It is rotatably supported.

  Further, as shown in FIG. 1, a scraping blade 75 is provided in the belt storage unit 68.

  The scraping blade 75 is formed in a substantially flat plate shape extending in the vertical direction, and the upper end portion (base end portion) of the scraping blade 75 is a belt storage so that the lower end portion (free end portion) is in contact with the relay roller 74 from the left side. It is fixed to the right peripheral edge of the opening 69 in the right wall of the portion 68.

  The belt storage unit 68 is connected to a belt waste toner transport pipe 70 as an example of a belt transport member.

  As shown in FIG. 6, the belt waste toner conveyance pipe 70 is formed in a substantially pipe shape, and a substantially coil spring-shaped screw 82 is accommodated therein.

  Further, the belt waste toner transport pipe 70 is formed in a substantially U shape in a side view in which both upper and lower ends are bent forward, and is inserted in the cartridge side as an example of a belt side connecting portion 76, a midway portion 77, and a belt separating portion. It is integrally formed with the part 78.

  The belt side connecting portion 76 is an upper end portion of the belt waste toner conveying pipe 70 and extends in the front-rear direction. The front end portion shares the central axis with the second auger screw 71 and communicates with the belt storage portion 68. As described above, the rear side wall 66 is fixed to the rear side wall 66, and the rear end portion extends through the rear wall of the inner casing 81.

  The intermediate portion 77 is bent downward from the rear end portion of the belt side connecting portion 76. Specifically, as shown in FIG. 1, the intermediate portion 77 is leftward from the rear end portion of the belt side connecting portion 76. After inclining downward as it goes, it bends and extends downward. Further, as shown in FIG. 6, the intermediate portion 77 is disposed between the rear wall of the outer casing 80 and the rear wall of the inner casing 81.

  The cartridge side insertion portion 78 is a lower end portion of the belt waste toner conveyance pipe 70, is bent forward from the lower end portion of the midway portion 77, and extends so as to penetrate the rear wall of the inner casing 81.

  The cartridge side insertion portion 78 has a belt waste toner discharge port 79 as an example of a belt opening.

  The belt waste toner discharge port 79 is formed to penetrate in the vertical direction at the front end portion of the lower side portion of the cartridge side insertion portion 78.

  The cartridge side insertion portion 78 includes a transport pipe side shutter 83 as an example of a belt shutter.

  The conveyance pipe side shutter 83 is formed in a substantially cylindrical shape extending in the front-rear direction, and is fitted to the cartridge side insertion portion 78 from the outside. Further, the inner diameter of the transport pipe side shutter 83 is formed to be substantially the same diameter (slightly larger) as the outer diameter of the cartridge side insertion portion 78. The transport pipe side shutter 83 closes the belt waste toner discharge port 79 and an open position (see FIG. 2) arranged at the rear end of the cartridge side insertion portion 78 so as to open the belt waste toner discharge port 79. Thus, it is slidably provided at a closed position (see FIG. 6) disposed at the front end portion of the cartridge side insertion portion 78. That is, the transport pipe side shutter 83 can open and close the belt waste toner discharge port 79.

A compression spring 84 is interposed between the rear end portion of the conveyance pipe side shutter 83 and the rear wall of the inner casing 81, and the conveyance pipe side shutter 83 is always moved forward by the compression spring 84. It is urged towards and is placed in the closed position.
4). Details of Developing Cartridge (1) Developing Frame As shown in FIG. 1, the cartridge frame 25 is formed in a substantially rectangular shape when viewed from the front, and its right side portion is partitioned as a developing device accommodating portion 32, and its left side portion is waste development. A waste toner container 31 as an example of the agent container is defined.
(1-1) Developing Device Housing Unit The developing device housing portion 32 is formed in a length in the front-rear direction capable of housing the developing device 24 as shown in FIG. Further, as shown in FIG. 7 (b), the developing device accommodating portion 32 is formed in a substantially U-shape that is opened upward, and the front wall 105 and the rear surface that are opposed to each other with an interval in the front-rear direction. The wall 106 and the lower wall 104 constructed between those lower end parts are provided.

  As shown in FIG. 8, the front wall 105 and the rear wall 106 are formed in a substantially flat plate shape that is substantially rectangular in a rear view.

  A guide hole 107 is formed in each of the front wall 105 and the rear wall 106.

  Two guide holes 107 are formed at portions corresponding to bosses 88 (described later) of the developing device 24, and two guide holes 107 are formed at intervals in the vertical direction.

  The guide hole 107 is formed in a substantially elliptical shape when viewed from the back, and is formed so as to extend along a facing direction X (described later) between the photosensitive drum 21 and the developing roller 26. The guide hole 107 has a major axis that is approximately 1.5 times as long as an outer diameter of a corresponding boss 88 (described later), and a minor diameter of the guide hole 107 is an outer diameter of the corresponding boss 88 (described later). And approximately the same diameter.

  The front wall 105 is formed with a grip portion 120 for attaching and detaching the developing cartridge 16 to and from the main casing 2.

  The grip portion 120 is formed in a substantially rectangular shape in a side view extending forward from the lower end portion of the front surface of the front wall 105.

  As shown in FIG. 3, the lower wall 104 is provided with a spring support portion 108.

  The spring support portion 108 is formed in a substantially triangular shape in front view extending in the front-rear direction.

  The spring support portion 108 is provided at the left end portion of the lower wall 104, and the upper surface facing the outer surface of the toner storage portion 29 is formed as a curved surface 110 when the developing device 24 is stored in the developing device storage portion 32. Has been. The curved surface 110 is formed in a substantially arc shape in front view that curves upward as it goes to the left.

  The spring support 108 is provided with a coil spring 109 as an example of an urging member.

  As shown in FIG. 7B, the coil spring 109 is formed in an air-core coil shape, and its axial direction is substantially parallel to a facing direction X (described later) between the photosensitive drum 21 and the developing roller 26 (described later). 3) and are fixed to the front and rear ends of the curved surface 110, respectively.

  Further, as shown in FIG. 7A, the developing device 24 is accommodated in the developing device accommodating portion 32.

  The developing device 24 is formed in a hollow cylindrical shape extending in the front-rear direction (see FIG. 1), and its front end is closed by a front wall 86 and its rear end is closed by a rear wall 87.

  In the present embodiment, the configurations relating to the front wall 86 and the rear wall 87 are the same. Therefore, in the following description, the rear wall 87 will be described in detail, and description of the front wall 86 will be omitted.

  A boss 88 is provided on the rear wall 87.

  As shown in FIGS. 7A and 8A, the boss 88 is formed in a substantially cylindrical shape that protrudes rearward from the rear wall 87. In the left portion of the rear wall 87, the boss 88 is spaced apart in the vertical direction. Two are provided apart. Further, the upper boss 88 has a larger diameter than the lower boss 88 as shown in FIG.

  7A, the developing device 24 is accommodated in the developing device accommodating portion 32 so that the boss 88 is inserted from the inside into the corresponding guide hole 107. As shown in FIG.

  As a result, the developer 24 can be relatively moved along the facing direction X (described later) between the photosensitive drum 21 and the developing roller 26 by the bosses 88 being guided in the corresponding guide holes 107. 32.

Further, as shown in FIG. 3, the coil spring 109 is disposed between the spring support portion 108 and the outer surface of the toner storage portion 29 of the developing device 24.
(1-2) Waste Toner Storage Unit As shown in FIG. 1, the waste toner storage unit 31 is formed in a substantially box shape having a substantially rectangular shape when viewed from the front in the vertical direction, and is disposed at the left end of the developer storage unit 32. It is connected.

  As shown in FIGS. 7B and 7C, the waste toner container 31 includes a third auger screw 89.

  The third auger screw 89 extends in the front-rear direction and is disposed on the upper portion of the waste toner storage unit 31 (see FIG. 1), and is rotatably supported on the front wall of the waste toner storage unit 31 at the front end thereof. The rear end portion is rotatably supported by the rear wall of the waste toner storage unit 31. Further, the rear end portion of the third auger screw 89 passes through the rear wall of the waste toner storage portion 31, and the coupling 95 is held so as not to rotate relative to the through portion.

  As shown in FIG. 7B, the third auger screw 89 in the black developing cartridge 16K is formed so that the spiral winding direction is reversed between the front half and the rear half. On the other hand, the third auger screw 89 in the other developing cartridges 16Y, 16M, and 16C (yellow developing cartridge 16Y, magenta developing cartridge 16M, and cyan developing cartridge 16C) is formed so that the spiral winding direction is the same direction. Yes.

  Further, the waste toner container 31 (hereinafter referred to as waste toner container 31K) in the black developing cartridge 16K has an insertion port 112 and a cartridge side receiving cylinder 90 as shown in FIG. 7B. ing.

  The insertion port 112 is formed to penetrate in the front-rear direction at the upper end portion of the rear wall of the waste toner storage portion 31K. The hole diameter of the insertion port 112 is formed to be substantially the same (slightly larger) as the outer diameter of the cartridge side insertion portion 78.

  The cartridge side receiving cylinder 90 is formed in a substantially cylindrical shape extending forward from the peripheral end of the insertion port 112, and the front end thereof is closed. That is, the cartridge-side receiving cylinder 90 is disposed in the waste toner container 31K.

  The cartridge-side receiving cylinder 90 has a belt waste toner receiving port 92 formed in the lower part thereof.

  The belt waste toner receiving port 92 is formed to penetrate in the vertical direction at the rear end portion of the lower portion of the cartridge side receiving cylinder 90 so as to communicate the waste toner container 31K and the cartridge side receiving cylinder 90.

  The cartridge side receiving cylinder 90 includes a cartridge side shutter 91.

  The cartridge side shutter 91 is formed in a substantially cylindrical shape extending in the front-rear direction with the rear end portion closed, and is accommodated in the cartridge side receiving cylinder 90. The outer diameter of the cartridge side shutter 91 is formed to be substantially the same as the inner diameter of the cartridge side receiving cylinder 90. The cartridge-side shutter 91 has an open position (see FIG. 2) disposed at the front end of the cartridge-side receiving cylinder 90 so as to open the belt waste toner receiving port 92 in the cartridge-side receiving cylinder 90, and a belt waste. The toner receiving port 92 is slidably provided at a closed position (see FIG. 7B) disposed at the rear end of the cartridge side receiving cylinder 90 so as to close the toner receiving port 92.

  A compression spring 93 is interposed between the front wall of the cartridge side receiving cylinder 90 and the rear wall of the cartridge side shutter 91, and the cartridge side shutter 91 is always moved rearward by the compression spring 93. It is urged towards and is placed in the closed position.

  The waste toner container 31 is connected to a drum waste toner transport pipe 96 as an example of a drum transport member.

  As shown in FIG. 7, the drum waste toner conveying pipe 96 is formed in a substantially pipe shape, and a substantially coil spring-shaped screw 94 is accommodated therein (see FIG. 1).

  Further, as shown in FIG. 7B, the drum waste toner transport pipe 96 is formed in a substantially U-shape in plan view with both front and rear ends bent toward the rear side, The unit 98 is integrally formed with a drum side insertion unit 99 as an example of a drum separation unit.

  The accommodating portion side connecting portion 97 is a left end portion of the drum waste toner conveying pipe 96 and extends in the front-rear direction. The rear end portion shares the central axis with the third auger screw 89 and is disposed in the waste toner accommodating portion 31. It is fixed to the front wall of the waste toner container 31 so as to communicate with each other.

  The midway portion 98 is bent rightward from the front end portion of the accommodating portion side connecting portion 97 and extends so as to incline upward toward the right (see FIG. 1).

  The drum side insertion portion 99 extends from the right end portion of the midway portion 98 by being bent backward.

  The drum side insertion portion 99 is formed with a drum waste toner receiving port 100 as an example of a drum opening.

  The drum waste toner receiving port 100 is formed so as to penetrate in the vertical direction at the rear end portion in the upper portion of the drum side insertion portion 99.

  In addition, the drum side insertion unit 99 includes a flange portion 102 and a pipe side shutter 101 as an example of a drum shutter.

  The flange portion 102 is provided on the outer peripheral surface of the front portion of the drum side insertion portion 99, and is formed in an annular plate shape that spreads outward in the radial direction of the drum side insertion portion 99.

  The pipe-side shutter 101 is formed in a substantially cylindrical shape extending in the front-rear direction, and is fitted to the drum-side insertion portion 99 from the outside. Further, the inner diameter of the pipe-side shutter 101 is formed to be approximately the same diameter (slightly larger) as the outer diameter of the drum-side insertion portion 99. The pipe-side shutter 101 has an open position (see FIG. 5B) disposed at the front end of the drum-side insertion portion 99 so as to open the drum waste toner receiving port 100, and the drum waste toner receiving port 100. It is slidably provided at a closed position (see FIG. 7B) disposed at the rear end portion of the drum side insertion portion 99 so as to be closed. That is, the pipe-side shutter 101 can open and close the drum waste toner receiving port 100.

A compression spring 103 is interposed between the front end portion of the pipe-side shutter 101 and the front side surface of the flange portion 102, and the pipe-side shutter 101 is always directed toward the rear side by the compression spring 103. Energized and placed in the closed position.
5). Next, the attaching / detaching operation of the developing cartridge 16 with respect to the main casing 2 will be described.

  In order to attach the developing cartridge 16 to the main casing 2, as shown in FIG. 6, first, the front cover 6 is positioned in the open position, and the grip portion 120 is gripped toward the cartridge housing space 115. The developing cartridge 16 is inserted from the front side.

  Then, the lower end portion of the cartridge frame 25 of the developing cartridge 16 is inserted into the holding member 20 from the front side. That is, the holding member 20 is arranged to support the cartridge frame 25 from below, and the developing cartridge 16 is guided by the holding member 20 and moved along the front-rear direction. At this time, the developing device 24 passes through the corresponding cartridge groove 52.

  Further, when the developing cartridge 16 is moved rearward with respect to the main casing 2, the pipe-side shutter 101 passes through the insertion port 53 from the front side as shown in FIG. The upper portion of the end portion is in contact with the lower side of the front end portion of the drum storage portion 54, and the rear end portion of the drum side insertion portion 99 is in contact with the front end portion of the drum unit side shutter 63.

  When the developing cartridge 16 is further moved rearward, the pipe-side shutter 101 is pressed forward against the urging force of the compression spring 103 by the drum storage portion 54 and disposed at the open position.

  At this time, the drum-side insertion portion 99 is inserted into the drum unit-side receiving cylinder 56 until the drum waste toner discharge port 62 and the drum waste toner receiving port 100 face each other in the vertical direction.

  As a result, the pipe-side shutter 101 and the drum unit-side shutter 63 are disposed at the open position, and the drum waste toner discharge port 62 and the drum waste toner receiving port 100 face each other in the vertical direction and communicate with each other.

  That is, as shown in FIG. 1, the drum waste toner transport pipe 96 has a left end portion (rear end portion of the accommodating portion side connecting portion 97) connected to a front end portion of the waste toner accommodating portion 31 and a right end portion (drum side). The rear end portion of the insertion portion 99 is connected to the front end portion of the drum storage portion 54.

  Further, as shown in FIG. 2, when the black developing cartridge 16 </ b> K is inserted into the cartridge housing space 115 from the front side, the peripheral end portion of the insertion port 112 in the rear wall 106 is in front of the front end portion of the transport pipe side shutter 83. The rear end portion of the cartridge side shutter 91 is in contact with the front end portion of the cartridge side insertion portion 78 (see FIGS. 6 and 7B).

  When the black developing cartridge 16K is further moved rearward, the peripheral end portion of the insertion port 112 presses the transport pipe side shutter 83 rearward against the urging force of the compression spring 84, and the transport pipe side The shutter 83 is disposed at the open position.

  At this time, the cartridge side insertion portion 78 is inserted into the cartridge side receiving cylinder 90 until the belt waste toner discharge port 79 and the belt waste toner receiving port 92 are opposed to each other in the vertical direction.

  As a result, the transport pipe side shutter 83 and the cartridge side shutter 91 are disposed at the open position, and the belt waste toner discharge port 79 and the belt waste toner receiving port 92 face each other in the vertical direction and communicate with each other.

  That is, as shown in FIG. 1, the belt waste toner transport pipe 70 has a left end (front end of the cartridge side insertion portion 78) connected to the rear end of the waste toner storage portion 31 and a right end (belt side connection). The rear end portion of the portion 76 is connected to the rear end portion of the belt storage portion 68 (see FIG. 2).

  Thus, the mounting of the developing cartridge 16 to the main casing 2 (cartridge accommodating space 115) is completed.

  At this time, the developing roller 26 of the developing cartridge 16 is brought into contact with the photosensitive drum 21 of the drum unit 15 from the lower left side as shown in FIG. That is, the developing roller 26 and the photosensitive drum 21 are opposed to each other in the facing direction X.

  Further, the spring support portion 108 of the developing device housing portion 32 is provided at the left end portion of the lower wall 104 of the cartridge frame 25 and is disposed on the opposite side of the photosensitive drum 21 with respect to the developing roller 26.

  Further, since the coil spring 109 is disposed between the curved surface 110 of the spring support portion 108 and the toner storage portion 29 so that the axial direction is substantially parallel to the facing direction X, the developing device 24 is urged. By urging along the direction Y, the developing roller 26 is urged toward the photosensitive drum 21.

  The holding member 20 accommodates the lower portion of the cartridge frame 25 and is disposed on the opposite side of the coil spring 109 with respect to the cartridge frame 25 (spring support portion 108). Thereby, the holding member 20 fixes the cartridge frame 25 to the inner casing 81.

  Note that, in order to detach the developing cartridge 16 from the main casing 2 (cartridge housing space 115), the procedure is reversed to the above-described mounting operation.

  Then, as shown in FIG. 6, the developing cartridge 16 is guided by the holding member 20 and pulled out from the cartridge housing space 115 to the front side.

  That is, the attaching / detaching direction of the developing cartridge 16 with respect to the main casing 2 and the axial direction of the photosensitive drum 21 are the same direction (front-rear direction), and the holding member 20 guides the attaching / detaching of the developing cartridge 16 to the main casing 2. .

  At this time, the connection between the drum side insertion portion 99 of the drum waste toner conveyance pipe 96 and the drum storage portion 54 (see FIG. 5B) is released, and the cartridge side insertion portion 78 of the belt waste toner conveyance pipe 70, The connection with the waste toner container 31K (see FIG. 7B) of the black developing cartridge 16K is released.

  That is, the drum side insertion portion 99 is configured to be able to be disconnected from the drum storage portion 54 (see FIG. 5B), and the cartridge side insertion portion 78 is configured to be the waste toner storage portion 31K (see FIG. 7B). ) Can be disconnected.

  The pipe-side shutter 101 is disposed at the closed position by the compression spring 103 (see FIG. 7A), and the transport pipe-side shutter 83 is disposed at the closed position by the compression spring 84.

  That is, as shown in FIG. 7A, the drum waste toner receiving port 100 is connected to the pipe side in a state where the connection between the drum side insertion portion 99 and the drum storage portion 54 (see FIG. 5B) is released. It is closed by the shutter 101. Further, as shown in FIG. 6, the belt waste toner discharge port 79 is a shutter on the conveyance pipe side when the connection between the cartridge side insertion portion 78 and the waste toner storage portion 31K (see FIG. 7B) is released. It is closed by 83.

  As described above, the attachment and detachment of the developing cartridge 16 with respect to the main casing 2 (cartridge accommodating space 115) is completed.

That is, the developing cartridge 16 is attached to and detached from the main casing 2 in a state where the photosensitive drum 21 is accommodated in the main casing 2 as described above.
6). Waste toner collection and storage (cleaning operation)
When the image forming operation of the color printer 1 is started, the first auger screw 58, the second auger screw 71, the third auger screw 89, and the drum are driven by a driving force from a driving source (motor) (not shown) in the main body casing 2. The screw 94 in the waste toner conveyance pipe 96 and the screw 82 in the belt waste toner conveyance pipe 70 rotate.

  In the image forming operation of the color printer 1, as described above, the toner image carried on the surface of the photosensitive drum 21 is primarily transferred sequentially to the lower portion of the intermediate transfer belt 38 that is moved from the left side to the right side. The

  At this time, after the primary transfer to the lower part of the intermediate transfer belt 38, the transfer residual toner (waste toner) remains on the surface of the photosensitive drum 21 without being transferred to the paper P.

  When the photosensitive drum 21 rotates, waste toner on the photosensitive drum 21 is scraped off by the drum scraping blade 55 and falls into the drum storage portion 54 through the opening 57.

  That is, the drum scraping blade 55 removes waste toner from the surface of the photosensitive drum 21 and collects it in the drum storage unit 54.

  Thereafter, the waste toner that has fallen into the drum storage unit 54 (the waste toner collected by the drum scraping blade 55) is stored in the drum storage unit 54 and the first auger screw 58 as shown in FIG. , The belt storage portion 68 is conveyed forward. Then, the waste toner that has reached the front end of the belt storage unit 68 falls from the drum waste toner discharge port 62 into the drum side insertion unit 99 through the drum waste toner receiving port 100 due to gravity.

  Waste toner that has fallen into the drum-side insertion portion 99 is conveyed from the drum-side insertion portion 99 to the storage portion-side connection portion 97 via the intermediate portion 98 by the rotation of the screw 94.

  Then, the waste toner conveyed into the storage unit side connection unit 97 is transported into the waste toner storage unit 31 by the rotation of the third auger screw 89.

  That is, the drum waste toner transport pipe 96 transports the waste toner from the drum storage unit 54 to the waste toner storage unit 31.

  Thereafter, the waste toner transported into the waste toner container 31K of the black developing cartridge 16K is transported rearward by the rotation of the third auger screw 89, and is stored in the central portion in the front-rear direction of the waste toner container 31K. The

  On the other hand, the waste toner transported into the waste toner container 31 of the other developing cartridges 16Y, 16M, and 16C is transported rearward by the rotation of the third auger screw 89, and the rear side of the waste toner container 31 Contained in the part.

  Next, as described above, the color image formed on the intermediate transfer belt 38 is applied to the paper P supplied from the paper feeding unit 4 while the intermediate transfer belt 38 passes through the position facing the secondary transfer roller 35. Secondary transfer.

  At this time, after the color image is secondarily transferred to the paper P, residual transfer toner (waste toner) remains on the intermediate transfer belt 38. When the waste toner faces the belt cleaning roller 72 due to the circumferential movement of the intermediate transfer belt 38, the waste toner is collected from the intermediate transfer belt 38 to the peripheral surface of the belt cleaning roller 72. As a result, the waste toner is removed from the intermediate transfer belt 38.

  Thereafter, when the waste toner carried on the peripheral surface of the belt cleaning roller 72 faces the relay roller 74 as the belt cleaning roller 72 rotates, the toner is discarded from the peripheral surface of the belt cleaning roller 72 to the peripheral surface of the relay roller 74. Toner adheres.

  When the relay roller 74 rotates, the waste toner on the peripheral surface of the relay roller 74 is scraped off by the scraping blade 75 and falls into the belt storage unit 68.

  Thereafter, as shown in FIG. 6, the waste toner that has fallen into the belt storage unit 68 is stored in the belt storage unit 68, and the belt storage unit 68 is directed rearward by the rotation of the second auger screw 71. And is sent from the belt reservoir 68 to the belt waste toner transport pipe 70.

  The waste toner sent into the belt waste toner conveyance pipe 70 is conveyed by the screw 82 from the belt side connecting portion 76 to the cartridge side insertion portion 78 through the intermediate portion 77.

  Then, the waste toner conveyed into the cartridge side insertion portion 78 is fed from the belt waste toner discharge port 79 through the belt waste toner receiving port 92 due to gravity, and is sent to the waste toner storage portion 31K (the waste toner in the black developing cartridge 16K). It falls into the accommodating part 31).

  Thereafter, the waste toner that has fallen into the waste toner container 31K is conveyed forward by the rotation of the third auger screw 89, and is stored in the central portion in the front-rear direction of the waste toner container 31K.

  That is, the belt waste toner transport pipe 70 transports the waste toner from the belt storage unit 68 to the waste toner storage unit 31.

Thus, the cleaning operation of the color printer 1 is completed.
7). Effects (1) In the color printer 1, as shown in FIG. 6, the developing cartridge 16 can be attached to and detached from the cartridge housing space 115 of the main casing 2 in a state where the photosensitive drum 21 is stored in the main casing 2. It is. Therefore, the developing cartridge 16 having a shorter lifetime than the photosensitive drum 21 can be replaced independently of the photosensitive drum 21.

  Further, as shown in FIG. 3, in a state where the developing cartridge 16 is housed in the cartridge housing space 115 of the main body casing 2, the spring support portion 108 of the cartridge frame 25 is on the opposite side of the photosensitive drum 21 with respect to the developing roller 26. Is arranged. Further, the developing device 24 including the developing roller 26 is accommodated so as to be movable relative to the cartridge frame 25 including the waste toner accommodating portion 31.

  And the coil spring 109 is provided in the curved surface 110 of the spring support part 108 in the front-back both ends.

  The coil spring 109 is disposed between the curved surface 110 and the outer surface of the toner accommodating portion 29 of the developing device 24 so that the axial direction is parallel to the facing direction X.

  Therefore, the biasing direction Y in which the coil spring 109 biases the developing device 24 (developing roller 26) toward the photosensitive drum 21 and the facing direction X of the developing roller 26 and the photosensitive drum 21 are substantially parallel. .

  As a result, the urging force of the coil spring 109 acts along the facing direction X between the developing roller 26 and the photosensitive drum 21, so that the developing roller 26 can be stably pressed toward the photosensitive drum 21. The relative positioning accuracy between the roller 26 and the photosensitive drum 21 can be improved.

Therefore, the relative positioning accuracy between the developing roller 26 and the photosensitive drum 21 can be improved while the waste toner storage unit 31 can be stored compactly.
(2) The drum unit 15 includes a drum cleaner 23 as shown in FIG. As shown in FIG. 4, the drum cleaner 23 includes a drum scraping blade 55 and a drum storage portion 54.

  Therefore, in the image forming operation of the color printer 1, waste toner remaining on the surface of the photosensitive drum 21 after the primary transfer is removed from the surface of the photosensitive drum 21 by the drum scraping blade 55, and the drum is temporarily stored. Part 54 can be collected.

  As shown in FIG. 5B, the drum waste toner transport pipe 96 is connected to the drum unit-side receiving cylinder 56 of the drum reservoir 54, so that the waste toner collected in the drum reservoir 54 The waste toner can be transported from the drum storage unit 54 to the waste toner storage unit 31 via the waste toner transport pipe 96 and stored in the waste toner storage unit 31.

As a result, waste toner on the surface of the photosensitive drum 21 can be collected and stored while improving the relative positioning accuracy between the developing roller 26 and the photosensitive drum 21.
(3) Further, as shown in FIG. 1, the drum waste toner transport pipe 96 has a left end portion (a rear end portion of the accommodating portion side coupling portion 97) connected to a front end portion of the waste toner accommodating portion 31, The rear end portion of the drum-side insertion portion 99 is connected to the front end portion of the drum storage portion 54.

  Therefore, the waste toner collected by the drum scraping blade 55 can be transported to the waste toner container 31 from the front side in the main body casing 2 while ensuring an efficient arrangement of the drum waste toner transport pipe 96.

Further, since the drum waste toner transport pipe 96 is fixed to the front surface of the front wall 105 of the developing device housing portion 32, the drum unit 15 is housed in the main body casing 2 and the developing cartridge 16 is attached to the main body casing 2. Smooth attachment / detachment can be ensured.
(4) Further, the drum waste toner conveying pipe 96 has a drum side insertion portion 99 as shown in FIG. The drum side insertion unit 99 includes a drum waste toner receiving port 100 and a pipe side shutter 101.

  The drum-side insertion portion 99 is connected to the drum storage portion 54 in a state where the developing cartridge 16 is mounted on the main casing 2 as shown in FIG. 5B, and as shown in FIG. In the state where 16 is detached from the main casing 2, the connection with the drum storage portion 54 (see FIG. 5B) is released.

  Therefore, the drum cleaner 23 disposed adjacent to the photosensitive drum 21 and the waste toner storage unit 31 provided in the cartridge frame 25 can be separated. As a result, the developing cartridge 16 can be replaced independently of the drum cleaner 23.

  Further, as shown in FIG. 7A, the drum waste toner receiving port 100 is connected to the pipe side in a state where the connection between the drum side insertion portion 99 and the drum storage portion 54 (see FIG. 5B) is released. It is closed by the shutter 101.

Therefore, the waste toner can be prevented from leaking from the drum waste toner receiving port 100.
(5) Further, the belt unit 34 includes an intermediate transfer belt 38 and a belt cleaner 40 as shown in FIG.

  The belt cleaner 40 includes a belt recovery unit 65 including a belt cleaning roller 72 and a relay roller 74, and a belt storage unit 68 provided with a scraping blade 75.

  Therefore, in the image forming operation of the color printer 1, the waste toner remaining on the intermediate transfer belt 38 after the secondary transfer can be removed from the intermediate transfer belt 38 by the belt cleaning roller 72. The waste toner removed by the belt cleaning roller 72 can be temporarily collected in the belt storage unit 68 from the belt cleaning roller 72 via the relay roller 74.

  As shown in FIG. 6, the belt waste toner transport pipe 70 is connected to the belt storage unit 68, so that the waste toner collected in the belt storage unit 68 is passed through the belt waste toner transport pipe 70. The toner can be conveyed from the belt storage unit 68 to the waste toner storage unit 31 and stored in the waste toner storage unit 31.

As a result, waste toner on the surface of the intermediate transfer belt 38 can be collected and accommodated while improving the relative positioning accuracy between the developing roller 26 and the photosensitive drum 21.
(6) Further, the belt waste toner transport pipe 70 has a cartridge side insertion portion 78. The cartridge side insertion portion 78 has a belt waste toner discharge port 79 and a transport pipe side shutter 83.

  The cartridge side insertion portion 78 is connected to the waste toner storage portion 31K (see FIG. 7B) of the black developing cartridge 16K in a state where the developing cartridge 16 is mounted on the main body casing 2, and the developing cartridge 16 is connected to the main body casing. In the state of being detached from the casing 2, the connection with the waste toner container 31K (see FIG. 7B) is released.

  Therefore, the belt cleaner 40 disposed adjacent to the intermediate transfer belt 38 and the waste toner storage unit 31 provided in the cartridge frame 25 can be separated. As a result, the black developing cartridge 16K can be replaced independently of the belt cleaner 40.

The belt waste toner discharge port 79 is closed by the transport pipe side shutter 83 in a state where the connection between the cartridge side insertion portion 78 and the waste toner storage portion 31K (see FIG. 7B) is released. Therefore, the waste toner can be prevented from leaking from the belt waste toner discharge port 79.
(7) Further, as shown in FIG. 1, the belt waste toner conveyance pipe 70 has a left end portion (a front end portion of the cartridge side insertion portion 78) connected to a rear end portion of the waste toner storage portion 31K of the black developing cartridge 16K. The right end portion (the rear end portion of the belt side connecting portion 76) is connected to the rear end portion of the belt storing portion 68 (see FIG. 2).

  Therefore, in the main casing 2, the drum waste toner transport pipe 96 is disposed on the front side with respect to the waste toner storage portion 31 </ b> K, and the belt waste toner transport pipe 70 is disposed on the rear side with respect to the waste toner storage portion 31 </ b> K. ing.

  The waste toner collected by the drum cleaner 23 can be conveyed from the front side to the waste toner storage unit 31K, and the waste toner collected by the belt cleaner 40 can be conveyed from the rear side to the waste toner storage unit 31K. be able to.

  As a result, efficient arrangement of the drum waste toner conveyance pipe 96 and the belt waste toner conveyance pipe 70 can be ensured, and the waste toner collected from the surface of the photosensitive drum 21 and the waste collected from the intermediate transfer belt 38 can be secured. The toner can be stored in a common waste toner storage unit 31K.

  Therefore, the waste toner storage portion 31K can be accommodated in a compact manner while ensuring efficient arrangement of the drum waste toner transport pipe 96 and the belt waste toner transport pipe 70.

Further, since the belt waste toner conveyance pipe 70 is fixed to the rear side wall 66 corresponding to the belt storage portion 68, the smooth attachment / detachment of the developing cartridge 16 to the main casing 2 can be ensured.
(8) Further, the cartridge frame 25 includes a grip portion 120 as shown in FIG.

  For this reason, when the developer cartridge 16 is attached to and detached from the main casing 2, the grip portion 120 can be gripped, so that the smooth attachment and detachment operation of the developing cartridge 16 with respect to the main casing 2 can be ensured.

  In particular, the grip portion 120 is provided not on the developing device 24 that can move with respect to the main body casing 2 but on the cartridge frame 25 that is fixed to the main body casing 2. By attaching / detaching to / from the main casing 2, a stable attaching / detaching operation of the developing cartridge 16 can be secured.

Therefore, it is possible to suppress contact between the photosensitive drum 21 and another member (for example, the developing roller 16) during the attaching / detaching operation of the developing cartridge 16 with respect to the main body casing 2, and the photosensitive drum 21 and the other member (for example, for example). It is possible to prevent damage to the photosensitive drum 21 due to contact with the developing roller 16 or the like.
(9) In addition, as shown in FIG. 1, a plurality (four) of photosensitive drums 21 are provided corresponding to a plurality of colors (black, yellow, magenta, cyan), and are arranged in parallel in the left-right direction at intervals. Is arranged.

  Further, toner corresponding to each color (black, yellow, magenta, cyan) is stored in the toner storage unit 29 of the developing device 24.

Therefore, the color printer 1 can form a full color image.
(10) Further, the partition member 111 of the inner casing 81 is provided with a holding member 20 as shown in FIG.

  Therefore, in a state where the developing cartridge 16 is mounted in the cartridge housing space 115, the lower portion of the cartridge frame 25 of the developing cartridge 16 is accommodated in the holding member 20, so that the cartridge frame 25 is fixed to the inner casing 81. it can.

  As a result, the relative positional relationship between the coil spring 109 provided on the spring support portion 108 of the cartridge frame 25 and the photosensitive drum 21 can be accurately maintained.

Therefore, the coil spring 109 can reliably bias the developing roller 26 toward the photosensitive drum 21, and can further improve the relative positioning accuracy between the developing roller 26 and the photosensitive drum 21.
(11) The holding member 20 is disposed on the opposite side of the coil spring 109 with respect to the spring support portion 108.

  Therefore, the reaction to the cartridge frame 25 due to the urging force of the coil spring 109 can be received by the partition wall 111 via the holding member 20.

As a result, the biasing force of the coil spring 109 can be reliably applied to the developing roller 26 as shown in FIG. 3 while the cartridge frame 25 is securely fixed to the partition wall 111. Therefore, the coil spring 109 can reliably bias the developing roller 26 toward the photosensitive drum 21, and can further improve the relative positioning accuracy between the developing roller 26 and the photosensitive drum 21.
(12) The holding member 20 is disposed so as to support the cartridge frame 25 from the lower side. Therefore, the biasing force of the coil spring 109 acts on the developing roller 26 with certainty, so that the developing roller 26 can be reliably biased toward the photosensitive drum 21.

  The holding member 20 guides the attachment / detachment of the developing cartridge 16 with respect to the main casing 2.

Therefore, since the smooth mounting / demounting operation of the developing cartridge 16 can be ensured, the developing roller 26 and the developing device 24 can be prevented from contacting the photosensitive drum 21. As a result, damage to the photosensitive drum 21 can be suppressed.
(13) Further, as shown in FIG. 1, a plurality (four) of developing cartridges 16 are arranged below the belt unit 34 and the photosensitive drum 21. Accordingly, the drum cleaner 23 and the belt cleaner 40 are disposed above the waste toner storage unit 31.

  Therefore, when the waste toner is transported toward the waste toner container 31 by the belt waste toner transport pipe 70 and the drum waste toner transport pipe 96, gravity can be used. As a result, the waste toner can be stably conveyed to the waste toner storage unit 31.

DESCRIPTION OF SYMBOLS 1 Color printer 2 Main body casing 16 Developer cartridge 20 Holding member 21 Photosensitive drum 23 Drum cleaner 24 Developer 25 Cartridge frame 26 Developing roller 29 Toner accommodating part 31 Waste toner accommodating part 32 Developer accommodating part 38 Intermediate transfer belt 40 Belt cleaner 54 drum Storage unit 55 Drum scraping blade 65 Belt recovery unit 68 Belt storage unit 70 Belt waste toner transport pipe 78 Cartridge side insertion unit 79 Belt waste toner discharge port 83 Transport pipe side shutter 96 drum waste toner transport pipe 99 Drum insertion unit 100 Drum waste Toner receiving port 101 Pipe side shutter 109 Coil spring

Claims (12)

The device body;
A photosensitive drum rotatably supported by the apparatus body;
A developing cartridge that is detachably attached to the apparatus main body in a state where the photosensitive drum is supported by the apparatus main body,
The developing cartridge is
A developing device provided with a developing roller that is disposed opposite to the photosensitive drum and that supplies the developer to the photosensitive drum, and a developer accommodating portion that accommodates the developer when mounted on the apparatus main body; ,
A waste developer accommodating portion for accommodating the waste developer, and a housing for accommodating the developing device in a relatively movable manner,
The housing is disposed on the opposite side of the photosensitive drum with respect to the developing roller,
An image forming apparatus, wherein a biasing member that biases the developing roller toward the photosensitive drum is provided between the housing and the developing device. A drum collection unit including a drum collection unit that removes and collects the waste developer from the surface of the photosensitive drum; and a drum storage unit that stores the waste developer collected by the drum collection unit;
One end portion is connected to the waste developer storage portion, the other end portion is connected to the drum storage portion, and a drum transport member for transporting the waste developer from the drum storage portion to the waste developer storage portion; The image forming apparatus according to claim 1, further comprising: The drum conveying member is
One end portion is connected to one end portion in the axial direction of the photosensitive drum in the waste developer accommodating portion, and the other end portion is connected to one end portion in the axial direction in the drum storage portion. The image forming apparatus according to claim 2. The drum conveying member is
At least one of the one end part or the other end part has a drum separation part configured to be able to be disconnected from at least one of the waste developer storage part or the drum storage part,
The drum separator is
A drum opening, and a drum shutter capable of opening and closing the drum opening;
The drum opening is
4. The drum shutter according to claim 3, wherein the drum shutter is closed by the drum shutter in a state where the connection between the drum separation unit and at least one of the waste developer storage unit and the drum storage unit is released. Image forming apparatus. An endless belt disposed opposite to the photosensitive drum;
A belt recovery unit comprising: a belt recovery unit that removes and recovers the waste developer from the belt; and a belt storage unit for storing the waste developer recovered by the belt recovery unit;
A belt conveying member having one end connected to the waste developer container, the other end connected to the belt reservoir, and conveying the waste developer from the belt reservoir to the waste developer container; The image forming apparatus according to claim 1, further comprising: The belt conveying member is
At least one of the one end part or the other end part has a belt separation part configured to be able to be disconnected from at least one of the waste developer storage part or the belt storage part,
The belt separating portion is
A belt opening, and a belt shutter capable of opening and closing the belt opening;
The belt opening is
6. The belt shutter according to claim 5, wherein the belt shutter is closed by the belt shutter in a state where the connection between the belt separation unit and at least one of the waste developer storage unit and the belt storage unit is released. Image forming apparatus. An endless belt disposed opposite to the photosensitive drum;
A belt recovery unit comprising: a belt recovery unit that removes and recovers the waste developer from the belt; and a belt storage unit for storing the waste developer recovered by the belt recovery unit;
A belt conveying member having one end connected to the waste developer container, the other end connected to the belt reservoir, and conveying the waste developer from the belt reservoir to the waste developer container; With
The belt conveying member is
One end portion is connected to the other end portion in the axial direction of the photosensitive drum in the waste developer accommodating portion, and the other end portion is connected to the other end portion in the axial direction in the belt storage portion. The image forming apparatus according to claim 3.   The image forming apparatus according to claim 1, wherein the housing includes a grip portion for attaching and detaching the developing cartridge to and from the apparatus main body. A plurality of the photosensitive drums are provided corresponding to a plurality of colors, and are arranged in parallel at intervals from each other in a direction orthogonal to the axial direction of the photosensitive drums.
A plurality of the developing cartridges are provided corresponding to each of the plurality of photosensitive drums,
The apparatus main body is provided with an endless belt disposed on the upper side of the plurality of photosensitive drums so as to face the plurality of photosensitive drums,
The image forming apparatus according to claim 1, wherein a direction in which the developing cartridge is attached to and detached from the apparatus main body is the same direction as an axial direction of the photosensitive drum.   The apparatus main body is provided with a holding member for fixing the casing to the apparatus main body in a state where the developing cartridge is mounted on the apparatus main body. The image forming apparatus according to any one of 1 to 9.   The image forming apparatus according to claim 10, wherein the holding member is disposed on an opposite side of the urging member with respect to the housing.   12. The image forming apparatus according to claim 10, wherein the holding member is configured to support the housing from below and guides attachment / detachment of the developing cartridge with respect to the apparatus main body.

Images