JP2009086417A - Electrophotographic image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic image forming apparatus for detachably attaching process cartridges (PY, PM, PC, PK) to an apparatus body A, having a simple constitution for preventing an interior of the apparatus body A from being contaminated by toner flying during an opening and closing operation of a shutter in a toner transfer section between a toner supplying apparatus 34 and the process cartridges P, when the cartridges P are detached, and to provide an elimination means for shielding and cleaning a vibration-proof glass, in an image exposure apparatus. <P>SOLUTION: When a moving member 42 for supporting the cartridges P and a toner replenishing apparatus 34 is drawn to a drawing position which is outside the apparatus body A and the cartridges are replaced, the shutter is closed for the first time and the toner transfer section is shielded, or the shutter is opened and the toner transfer section is opened. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electrophotographic image forming apparatus in which a process cartridge is attached to and detached from an apparatus main body.

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

  The process cartridge is an apparatus body of an electrophotographic image forming apparatus in which an electrophotographic photosensitive drum and at least one of process means acting on the drum, such as a charging means, a developing means, and a cleaning means, are integrally formed into a cartridge. Can be attached to and detached from. The charging means is a process means for uniformly charging an electrophotographic photosensitive drum (hereinafter referred to as a drum) to a predetermined polarity and potential. The developing means is a process means for developing the electrostatic latent image formed on the drum as a toner image (developer image). The cleaning means is a process means for cleaning the surface of the drum after the toner image is transferred to another object.

  In the present invention, the process cartridge is a cartridge in which the electrophotographic photosensitive drum and at least developing means as process means are integrated into a cartridge and can be attached to and detached from the apparatus main body.

  The apparatus main body is an electrophotographic image forming apparatus portion excluding the process cartridge.

  Since the process cartridge can be attached to and detached from the apparatus main body by the user himself, the apparatus main body can be easily maintained.

  2. Description of the Related Art In recent years, image forming apparatuses that employ an electrophotographic system have become full-color, and four or more process cartridges (hereinafter referred to as cartridges) that form toner images of various colors are arranged. In order to reduce the size of the main body of the device and eliminate image defects due to the types of recording media such as plain paper, cardboard, and OHP sheets, the toner images formed on the drums of each cartridge are sequentially superimposed on the intermediate transfer belt. First transfer. A configuration in which the primary transfer toner image on the intermediate transfer belt is secondarily transferred to a recording medium is often used.

  Patent Documents 1 and 2 disclose an image forming apparatus in which each cartridge is disposed below the intermediate transfer belt, and an image exposure device for the drum is disposed below each cartridge. With this configuration, the distance from the cartridge to the secondary transfer portion can be shortened as much as possible, and the time until the secondary transfer of the toner image created by the primary transfer onto the intermediate transfer belt can be shortened, thereby shortening the print time. Is possible.

  As the cartridge is used for image formation, the developer (toner) contained in the developing means is consumed sequentially. Therefore, there is an image forming apparatus having a configuration in which a toner replenishing device for quantitatively replenishing toner contained in a toner cartridge or a toner hopper to the developing means of the cartridge is provided in the apparatus main body. When the cartridge is mounted on the main body, the toner inlet on the cartridge side and the toner outlet on the toner replenishing device correspond to each other, so that a proper amount of toner is supplied from the toner replenishing device to the cartridge side in a timely manner. Is done. A first shutter is disposed at the toner inlet portion on the cartridge side, and a second shutter is disposed at the toner outlet portion on the toner supply device side. When the cartridge is mounted on the apparatus main body, the first and second shutters are in the open position, and the toner inlet portion on the cartridge side and the toner outlet portion on the toner supply device side are open. It corresponds by the state. The first and second shutters are closed in conjunction with the movement of the cartridge in the removing direction when the cartridge is removed from the apparatus main body, and the toner inlet portion on the cartridge side and the toner outlet portion on the toner supply device side Is configured to be shielded. Further, the first and second shutters open in conjunction with the movement of the cartridge in the mounting direction when the cartridge is mounted on the apparatus main body, and the toner inlet portion on the cartridge side and the toner outlet portion on the toner supply device side Are configured to correspond to each other in an opened state.

  There is also an image forming apparatus having a configuration in which a cartridge, a toner cartridge, and a toner replenishing device are integrally attached to and detached from the apparatus main body. Also in this image forming apparatus, a first shutter is disposed at the toner inlet portion on the cartridge side, and a second shutter is disposed at the toner outlet portion on the toner supply device side. When the cartridge is mounted on the apparatus main body, the first and second shutters are in the open position, and the toner inlet portion on the cartridge side and the toner outlet portion on the toner supply device side are opened. is doing. As a result, an appropriate amount of toner is supplied from the toner supply device side to the cartridge side in a timely manner. To remove the cartridge from the apparatus main body, before the cartridge is pulled out from the apparatus main body, the first and second shutters are closed so that the toner inlet portion on the cartridge side and the toner outlet portion on the toner supply device side are shielded from each other. To do. The cartridge, the toner cartridge, and the toner replenishing device are integrally pulled out from the apparatus main body. When the cartridge is mounted on the apparatus main body, the cartridge, the toner cartridge, and the toner replenishing device are integrally pushed into the apparatus main body and moved to the mounting position. Thereafter, the first and second shutters are opened to open the toner inlet portion on the cartridge side and the toner outlet portion on the toner supply device side, respectively.

  By the way, in the image forming apparatus configured as described above, the opening and closing operations of the first and second shutters when the cartridge is attached to and detached from the apparatus main body are performed in a state where the cartridge exists in the apparatus main body. For this reason, image exposure is caused by a slight amount of scattered toner on the outside of the toner inlet portion on the cartridge side and the toner outlet portion on the toner supply device side due to the opening and closing operations of the first and second shutters. Falls on the device. The scattered toner falling on the image exposure apparatus stains the dust-proof glass that prevents the optical components of the image exposure apparatus from being stained.

  The dirt on the dust-proof glass partially blocks the image exposure light such as laser light emitted from the dust-proof glass, thereby causing deterioration of the formed image and affecting the optical characteristics. In particular, when the image exposure apparatus is provided in the lower part of the apparatus main body and the emission opening part faces upward, there is a strong risk of contamination on the dust-proof glass.

  Patent Document 2 discloses a technique for preventing and cleaning the dust-proof glass of the image exposure apparatus (optical unit) as described above. In this configuration, when the cartridge is attached to or detached from the apparatus main body, the vibration-proof glass on the image exposure apparatus is shielded and cleaned in conjunction with the opening operation of the apparatus main body opening that needs to be opened.

With this configuration, it is possible to prevent the scattered toner generated when the cartridge is attached and detached from adhering to the dustproof glass. In addition, it is possible to clean dust and toner dirt that has accumulated in the dust-proof glass before the cartridge is attached and detached.
JP 2003-287939 A JP 2004-085899 A

  The present invention is a further development of the conventional configuration described above. An object of the present invention is to prevent toner contamination in the apparatus main body caused by scattered toner accompanying opening / closing operation of a shutter when a cartridge is attached / detached with a simple configuration. In this way, an electrophotographic image forming apparatus is provided in which it is possible to omit the shielding of the image exposure apparatus from the vibration-proof glass and the arrangement of the cleaning means.

A typical configuration of the electrophotographic image forming apparatus according to the present invention for achieving the above object is as follows:
An electrophotographic process cartridge having an electrophotographic photosensitive drum and at least developing means for developing a latent image formed on the electrophotographic photosensitive drum with toner as process means acting on the electrophotographic photosensitive drum. In an electrophotographic image forming apparatus that detachably attaches to an apparatus main body of an image forming apparatus and forms an image on a recording medium.
An opening through which the process cartridge is inserted in order to insert the process cartridge into the inside of the apparatus main body and to remove the process cartridge from the inside of the apparatus main body;
A rail member is slidably held, and supports the process cartridge and a toner replenishing device that replenishes toner to the process cartridge. The process cartridge passes through the opening and is attached to the main body of the apparatus. A movable member capable of taking a drawer position that can be attached and detached on the outside, and a mounting position for mounting the process cartridge inside the apparatus main body;
A first toner transfer unit that transfers toner from the toner supply device to the process cartridge;
A first shutter for opening and closing an opening provided in the process cartridge, which constitutes the first toner passing portion, so as to shield and open the first toner passing portion; A second shutter for opening and closing the opening;
And the first shutter and the second shutter are closed when the moving member is pulled out to the pulling position and the process cartridge is replaced, thereby shielding the first toner passing portion. Or the first shutter and the second shutter are opened to open the first toner transfer unit.

  According to the present invention, in a state where the moving member supporting the process cartridge is pulled out to the pulling position outside the apparatus main body, the first and second shutters that shield and open the first toner transfer portion can be opened and closed. Made. Therefore, even if scattered toner is generated in accordance with the opening and closing operations of the first and second shutters, it is outside the apparatus main body, and therefore, the scattered toner does not fall on the image exposure apparatus in the apparatus main body. Defects can be prevented.

[Example 1]
<< Description of Overall Schematic Configuration of Electrophotographic Image Forming Apparatus Example >>
FIG. 1 is an external perspective view of the electrophotographic image forming apparatus of this embodiment, FIG. 2 is a schematic front view of the image forming apparatus, and FIG. 3 is a partially enlarged view of FIG.

  This image forming apparatus 1 is an inline type / intermediate transfer type electrophotographic image forming apparatus (copier, printer, facsimile, or the like) capable of forming a single color, a plurality of colors, or a full color image on a recording material S as a recording medium. MFP). Further, the image forming apparatus 1 can remove the first to fourth process cartridges P (PY, PM, PC, PK) from an image forming apparatus main body (hereinafter referred to as an apparatus main body) A. This is a process cartridge attaching / detaching method used by attaching.

  Here, regarding the image forming apparatus 1 of the present embodiment, the front side or the near side is the side on which the open / close door 2 is provided. The back side or the back side is the opposite side. The front-rear direction is a direction from the back side to the front side (front direction) and the opposite direction (rear direction). Left and right are left or right when the image forming apparatus 1 is viewed from the front side. The left-right direction is a direction from left to right (left direction) and the opposite direction (right direction). The apparatus main body A is an image forming apparatus portion other than a process cartridge (hereinafter referred to as a cartridge). With respect to the cartridge or its constituent members or the constituent members on the apparatus main body side, the longitudinal direction means the axial direction of an electrophotographic photosensitive drum (hereinafter referred to as drum) 4 as an image carrier or a direction parallel to the axial direction. is there. Regarding the cartridge, in the longitudinal direction, a side to which driving is transmitted from the apparatus main body side is referred to as a driving side, and the opposite side is referred to as a non-driving side.

  A document reading device (image scanner) B is disposed on the upper side of the apparatus main body A. On the lower side of the apparatus main body A, four first to fourth paper feed cassettes (paper feed units) C1, C2, C3, and C4 are arranged in four upper and lower stages. A manual feed tray C5 is disposed on the right side surface of the apparatus main body A. The manual feed tray C5 can be folded and stored in the right side surface of the apparatus main body A when not in use. D is an external input device (external host device) such as a personal computer / facsimile device and is electrically connected to a controller (control board, control circuit unit (CPU)) E built in the apparatus main body A via an interface. ing. The controller E controls the overall operation of the image forming apparatus.

  A cartridge housing portion 3 for housing each cartridge P is provided at the center of the apparatus main body A. The cartridges P are arranged and mounted at positions where images can be formed, arranged in the storage unit 3 in a vertically slanting direction downward from the left side to the right side with the longitudinal direction being the front-rear direction. That is, the leftmost first cartridge PY is the highest, the second cartridge PM is lower, the third cartridge PC is lower, the rightmost fourth cartridge PK is the lowest, and the lower right and upside They are arranged in an oblique direction.

  Let F be a virtual plane that passes through each rotation center O of the drum 4 of each cartridge P when each cartridge P is mounted at a position where an image can be formed in the storage unit 3. The inclination angle of the virtual plane F with respect to the horizontal plane G is defined as θ. In this embodiment, the inclination angle θ is set to approximately 20 °. In this way, the horizontal width of the apparatus main body A can be suppressed by arranging the plurality of cartridges P in the diagonally up and down direction.

  Each cartridge P has the same electrophotographic process mechanism except that the color of the developer (hereinafter referred to as toner) accommodated in the developing device is different. In the storage unit 3, a rotational driving force is transmitted from the apparatus main body A side to each cartridge P mounted at a position where an image can be formed, and a bias (charging bias, developing bias, etc.) is supplied (not shown). ).

  Each cartridge P of this embodiment includes an electrophotographic photosensitive drum (hereinafter referred to as a drum) 4 as an image carrier, and a charging device 5, a developing device 6, and a drum cleaner device as process means acting on the drum 4. 7 is integrally assembled in the cartridge frame 8. In this embodiment, the drum 4 is a negatively chargeable OPC photosensitive member, and has an aluminum drum base and a photoconductive layer formed on the peripheral surface of the drum base. A charging roller is used as a charging member of the charging device (charging means) 5. A developing roller is used as a developing member of the developing device (developing means) 6. A cleaning blade is used as a cleaning member of the drum cleaner device (cleaning means) 7.

  The first cartridge PY contains yellow (Y) toner in the developing container, and forms a Y toner image on the surface of the drum 4. The second cartridge PM contains magenta (M) toner in the developing container, and forms an M toner image on the surface of the drum 4. The third cartridge PC contains cyan (C) toner in the developing container, and forms a C toner image on the surface of the drum 4. The fourth cartridge PK contains black (K) toner in the developing container and forms a K toner image on the surface of the drum 4.

  Below each cartridge P, a laser exposure device (laser scanner) 9 as an image exposure device (image information exposure means) for the drum 4 is disposed. The laser exposure apparatus 9 includes a laser diode (not shown) as a laser light emitting element, a polygon mirror 11 rotated by a scanner motor 10, an imaging lens 12, a reflection mirror 13, and the like. Further, the laser exposure device 9 has an upward laser light emission opening 14 with respect to the drum 4 of each cartridge P, and a dust-proof glass 15 which is a light transmission member for dust prevention is provided. The laser light emitting element is a laser light emitting means for emitting light corresponding to a time-series electric digital pixel signal of image information given thereto.

  Further, an intermediate transfer belt unit 15 is disposed above each cartridge P. This unit 15 is a transfer means for primary transfer by superimposing a toner image formed on the drum 4 of each cartridge P on an intermediate transfer belt (hereinafter referred to as a belt) 16. The unit 15 includes a right driving roller 17 and an auxiliary roller 18 and a left tension roller 19, and a flexible endless belt 16 is wound around the three rollers 17, 18, and 19. Has been supported. And the belt 16 is arrange | positioned so that it may become diagonal with respect to a horizontal direction.

  In the cartridge storage portion 3, the drum 4 of each cartridge P mounted at a position where image formation is possible is in contact with the lower surface of the belt portion on the lower side of the belt 16. The contact portion is a primary transfer portion. A primary transfer roller 20 facing each drum 4 is disposed inside the belt 16 and is pressed against the upper surface of the drum 4 via the belt 16. The belt 16 is circulated and moved by the driving roller 17 in the counterclockwise direction indicated by the arrow at a speed corresponding to the rotational speed of the drum 4 in a state where the lower belt portion is in contact with the upper surface of all the drums 4 Driven. That is, the drive roller 17 includes a gear (not shown) on the roller shaft, and is driven to rotate by a drive gear (not shown) on the apparatus main body A side that meshes with the gear.

  A predetermined primary transfer voltage (bias) is applied to each primary transfer roller 20 at a predetermined control timing. The intermediate transfer belt unit 15 is held by a transfer frame 21 disposed in the apparatus main body A. Further, the transfer frame 21 incorporates a primary transfer power source 22 for applying a predetermined primary transfer voltage to each primary transfer roller 20.

  Here, the entire intermediate transfer belt unit 15 and the transfer frame 21 holding the intermediate transfer belt unit 15 are referred to as an intermediate transfer belt device.

  The drive roller 17 also serves as a secondary transfer counter roller, and the secondary transfer roller 23 is in contact with the drive roller 17 via the belt 16. A contact portion between the secondary transfer roller 23 and the belt 16 is a secondary transfer portion. A predetermined secondary transfer voltage is applied to the secondary transfer roller 23 from a secondary transfer power source (not shown) at a predetermined control timing.

  A belt cleaner device 24 that cleans the outer surface of the belt 16 is disposed at a belt suspension portion of the tension roller 19.

  The document reader B optically scans the image of the document set on the document reader B, and separates and reads the three primary colors of RGB (red, green, and blue) using a photoelectric conversion element. The read RGB signals are input to an image processing unit (not shown) of the controller E. The controller E controls the laser exposure device 9 to modulate the laser beams LY, LM, LC, and LK modulated according to each color separation read image information (electrical image information) from the document reading device B from the first to the fourth. Output to the drums 4 of the cartridges PY, PM, PC, and PK, respectively.

  In the laser exposure apparatus 9, the modulated laser beam output from a laser diode (not shown) is irradiated to the polygon mirror 11 that is rotationally driven. The polygon mirror 11 deflects and scans the irradiated laser beam. The laser light reflected from the polygon mirror 11 is emitted upward from an upward laser light emission opening 14 having an imaging lens 12, a reflection mirror 13, and a dust-proof glass 15, and the drum 4 of each cartridge P is scanned and exposed.

  In the printer mode, electrical image information input from the personal computer as the external input device D to the controller E is processed by the image processing unit, and the image forming apparatus 1 functions as a printer. In the facsimile reception mode, the electrical image information input from the counterpart facsimile machine as the external input device D to the controller E is processed by the image processing unit, and the image forming apparatus 1 functions as a facsimile reception apparatus. In the facsimile transmission mode, the electrical image information of the original photoelectrically read by the original reading apparatus B is transmitted by the controller E to the counterpart facsimile receiving apparatus as the external input device D, and the image forming apparatus 1 is used as the facsimile transmitting apparatus. Function.

  The operation for forming a full-color image is as follows. When an image formation start signal is issued, the controller E starts an image forming operation of the image forming apparatus. That is, the drums 4 of the first to fourth cartridges PY, PM, PC, and PK are rotationally driven at a predetermined speed (process speed) in the clockwise direction of the arrow by the driving device on the apparatus body A side. The belt 16 is also rotationally driven at a speed corresponding to the speed of the drum 4 in the counterclockwise direction of the arrow (forward direction with respect to the drum rotation). The laser exposure device 9 is also driven. In synchronization with this drive, in each cartridge P, the surface of the drum 4 is uniformly charged to a predetermined polarity and potential by a charging roller 5 to which a predetermined charging voltage is applied from a charging voltage power source (not shown). In this embodiment, the surface of the drum 4 is uniformly charged to a predetermined negative potential. The laser exposure device 9 scans and exposes the uniformly charged surface of each drum 4 with laser beams LY, LM, LC, and LK modulated according to the image information signals of the respective colors. Laser light output from the laser exposure device 9 enters the cartridge frame 8 from the bottom up through the slit window 8a provided on the bottom surface side of the corresponding cartridge P. Then, the lower surface of the drum 4 is scanned and exposed through a gap passage between the charging device 5 and the developing device 6. Thereby, an electrostatic latent image corresponding to the image information signal of the corresponding color is formed on the surface of each drum 4. The formed electrostatic latent image is developed (visualized) as a toner image by the developing roller of the developing device 5. In many cases, so-called image exposure and reversal development are used in combination. In this embodiment, negative toner (negatively charged toner) is adhered to the exposed bright portion of the drum 4 by a developing roller to which a developing bias having the same polarity as the charged polarity (negatively charged) of the drum 4 is applied. The latent image is developed as a toner image.

  By the electrophotographic image forming process operation as described above, a Y toner image corresponding to the yellow component of the full color image is formed on the drum 4 of the first cartridge PY. Then, the toner image is primarily transferred onto the belt 16. The primary transfer roller 20 is applied with a primary transfer voltage of a predetermined potential having a positive polarity that is opposite to the charging polarity of the toner. Similarly, an M color toner image corresponding to the magenta component of the full color image is formed on the drum 4 of the second cartridge PM. Then, the toner image is primary-transferred superimposed on the Y-color toner image already transferred onto the belt 16. Similarly, a C-color toner image corresponding to the cyan component of the full-color image is formed on the drum 4 of the third cartridge PC. Then, the toner image is primary-transferred superimposed on the Y color + M color toner image already transferred onto the belt 16. Similarly, a K toner image corresponding to the black component of the full color image is formed on the drum 4 of the fourth cartridge PK. Then, the toner image is primary-transferred superimposed on the Y color + M color + C color toner image already transferred onto the belt 16.

  In this way, a four-color full-color unfixed toner image of Y color + M color + C color + K color is synthesized and formed on the belt 16.

  In each cartridge P, the transfer residual toner remaining on the surface of the drum 4 after the primary transfer is removed from the drum surface by the drum cleaner device 7.

  On the other hand, the sheet feeding mechanism of the designated sheet feeding unit among the first to fourth sheet feeding cassettes C1, C2, C3, C4 and the manual feed tray C5, which are a plurality of sheet feeding units, operates, and The recording material S stored in the paper feeding unit is separated and fed. The fed recording material S is conveyed upward by a vertical conveyance path 25 formed substantially vertically and reaches the nip portion of the registration roller pair 26. The registration roller pair 26 sends the recording material S to the secondary transfer portion in synchronization with the toner image formation timing on the belt 16. That is, recording is performed so that the leading end of the recording material S reaches the secondary transfer portion in accordance with the timing at which the leading end of the unfixed full-color toner image synthesized and formed on the rotating belt 16 reaches the secondary transfer portion. The material S is conveyed by timing. As a result, the unfixed full-color toner image on the belt 16 is secondarily transferred in batch to the surface of the recording material S that is nipped and conveyed from the bottom to the top of the secondary transfer portion. While the recording material S is nipped and conveyed to the secondary transfer roller 23, a predetermined secondary transfer having a polarity opposite to the toner charging polarity from a secondary transfer voltage power source (not shown) is performed. A voltage is applied.

  The recording material S that has exited the secondary transfer portion is separated from the surface of the belt 16 and conveyed further upward in the vertical conveyance path 25, and is a fixing portion that is a pressure contact portion between the fixing roller 27a and the pressure roller 27b of the fixing device 27. It is introduced into the nip part. Then, while the recording material S is nipped and conveyed through the fixing nip portion, an unfixed full-color toner image is heated and pressurized and fixed on the surface of the recording material S. Then, the recording material S exits the fixing device 27 and is discharged as a full-color image formed product onto a paper discharge tray 29 which is the upper surface of the apparatus main body A by the paper discharge device 28.

  Further, the secondary transfer residual toner (waste toner) remaining on the surface of the belt 16 after the secondary transfer of the toner image to the recording material S is removed from the belt surface by the belt cleaner device 24.

  The image forming apparatus 1 is configured such that an additional additional paper discharge device 30 can be disposed as an optional unit above the paper discharge device 28.

  In the mono color print mode, only the cartridge of the selected color is controlled to perform the image forming operation.

In the case of the duplex printing mode, the recording material S is conveyed as follows. That is, the rear end portion of the recording material S on which the first surface image has been formed is discharged to the discharge tray 29 by the discharge device 28 through the fixing device 27 to the final discharge roller pair 28 a of the discharge device 28. However, the paper discharge roller pair 28a is controlled to rotate in reverse at the timing when the nip portion has not yet been removed. As a result, the recording material S is transported back to the double-sided transport path 31 and transported downward, and is retransmitted in a state where it is reversed with respect to the registration roller pair 26. Thereafter, as in the case of the single-sided printing mode, the recording material S is reintroduced into the secondary transfer portion by the rotational drive of the registration roller pair 26, and the secondary toner image on the second surface from the belt 16 side. The image is transferred and then introduced again into the fixing device 27. As a result, the recording material S on which the image has been formed on both the first surface and the second surface is discharged to the discharge tray 29 by the discharge device 28 in which the rotation of the discharge roller pair 28a is returned to the normal rotation. In the image forming apparatus of this embodiment, the four cartridges PY, PM, PC, and PK are arranged in the order of yellow, magenta, cyan, and black from the upstream side in the moving direction of the belt 16. The arrangement of each cartridge is not limited to this color order.

  FIG. 4 is a schematic development view of a toner supply system for the developing device 6 of the cartridge P and a waste toner recovery system from the drum cleaner device 7.

  A developing container 6a, which is a developer container of the developing device 6 of each cartridge P, is supplied from a toner cartridge T (TY, TM, TC, TK) containing toner of a corresponding color by a toner replenishing device 34. The toner is replenished quantitatively. Each toner cartridge T and toner supply device 34 are separate devices from the cartridge P. The toner cartridge T and the toner replenishing device 34 communicate with each other at a toner transfer portion (mutual communication opening portion) 33. Then, the toner in the toner cartridge T is sequentially supplied and supplied into the toner replenishing device 34 by the toner transfer unit 33. The toner in the toner cartridge T is agitated by the rotation of the agitating blade member 32 and broken into blocks.

  The toner replenishing device 34 and the developing container 6 a in the cartridge P are in communication with each other at the first toner transfer unit 36. In the first toner transfer section 36, the toner in the toner replenishing device 34 is quantitatively replenished into the developing container 6a by controlling the rotation of the screw shaft 35. For example, a means for detecting the remaining toner amount (or developer concentration (toner ratio relative to the carrier)) of each cartridge P is provided, and the controller E causes the detected remaining amount value to be compared with a preset threshold value. When the detected remaining amount reaches the threshold value, the screw shaft 35 of the toner replenishing device 34 is rotated by a predetermined number of rotations to quantitatively replenish the toner in the toner replenishing device 34 into the developing container 6a. By this toner replenishment control, the toner amount (or developer concentration) in the developing container 6a is maintained within a predetermined range. The toner in the developing container 6a and the toner replenished in the developing container 6a are circulated and conveyed while being stirred and mixed in the developing container 6a by the screw shafts 6b and 6c. A part of it is carried on the developing roller 6 d and consumed for developing the electrostatic latent image formed on the drum 4.

  Further, in each cartridge P, the transfer residual toner (waste toner) remaining on the surface of the drum 4 after the primary transfer of the toner image to the belt 16 is removed from the drum surface by the cleaning blade 7a of the drum cleaner device 7 and the cleaner container 7b. Accumulate inside. The waste toner in the cleaner container 7b is conveyed to one end side (non-driving side) in the longitudinal direction of the container by the screw shaft 7c, and is collected to the waste toner collecting apparatus 39 through the waste toner conveying apparatus 38. The waste toner collection device 39 is a waste toner box that stores waste toner conveyed by the waste toner conveyance device 38. The waste toner conveying device 38 and the waste toner collecting device 39 are separate devices from the cartridge P. The cleaner container 7 b in the cartridge P and the waste toner conveying device 38 communicate with each other at the second toner transfer unit 37. Then, the waste toner in the cleaner container 7 b is sent to the waste toner conveying device 38 by the second toner transfer unit 37.

  Although omitted in FIG. 4, the opening on the cartridge P side and the opening on the toner replenishing device 34 side, which constitute the first toner transfer unit 36, are respectively the first and the first for opening and closing the openings. Two shutters (toner shutters) are provided. The first and second shutters 36 are opened and closed by opening and closing operations of the first and second shutters. In addition, a third shutter (waste toner shutter) for opening and closing the opening is disposed in the opening on the cartridge P side constituting the second toner transfer portion 37. By opening and closing the third shutter, the second toner transfer portion 37 is opened and shielded. The first, second, and third shutters will be described later.

  In addition, waste toner that accumulates in the belt cleaner device 24 that removes secondary transfer residual toner from the intermediate transfer belt 16 is also sent to a waste toner storage device 39 from a communication unit (not shown) and collected.

<Cartridge replacement method>
An opening / closing door (opening / closing member: hereinafter referred to as a door) 2 is provided on the front side of the apparatus main body A. The door 2 can be opened and closed with respect to the apparatus main body A about a horizontal axis (hinge axis) 2b in the left-right direction on the lower side of the door. FIG. 1 shows a state in which the door 2 is raised with the hinge shaft 2b as a center and rotated in the direction to be closed with respect to the apparatus main body A. A handle 2 a is provided on the door 2. FIG. 5 shows a state in which the door 2 is opened by being pivoted almost horizontally toward the front side about the hinge shaft 2b. By opening the door 2, the opening 41 on the front side of the apparatus main body A is opened, and the image forming housing 42 as a moving member (front access pull-out tray) inside the apparatus main body is exposed.

  The image forming housing 42 includes cartridges PY, PM, PC, and PK, toner cartridges TY, TM, TC, and TK for each cartridge, a toner supply device 34, a waste toner transport device 38 for each cartridge P, and waste toner. A collection device 39 is supported.

  Rail members 44L and 44R (FIG. 6) that can be expanded and contracted horizontally in the front-rear direction are disposed on the inner side of the left frame 43L and the inner side of the right frame 43R of the main body casing that forms the skeleton of the apparatus main body A, respectively. . The image forming housing 42 is slidably held by the left and right rail members 44L and 44R.

  Accordingly, the image forming housing 42 supports the cartridge P, the toner cartridge T, the waste toner conveying device 38, and the waste toner collecting device 39, and as a process device, the left and right rail members 44L and 44R are attached to the apparatus main body A. It can move horizontally in the front-rear direction.

  The cartridges PY, PM, PC, and PK are supported by being arranged in the left-right direction with respect to the image forming housing 42 such that the axial direction of the drum 4 included in the cartridge is parallel to the moving direction of the image forming housing 42. Has been. The toner cartridges TY, TM, TC, and TK, the toner supply device 34, the waste toner transport device 38, and the waste toner collection device 39 are disposed and supported on the front frame plate portion of the image forming housing 42.

  Then, the image forming case 42 is moved by the rail members 44L and 44R, passes through the opened opening 41, and can be attached to and detached from the image forming case 42 outside the apparatus main body A (see FIG. 6. FIG. 7) can be taken. Further, the image forming housing 42 is moved by the rail members 44L and 44R, passes through the opening 41, and is mounted at a mounting position for mounting the cartridge P on the cartridge mounting portion 3 inside the apparatus main body A (FIG. 2 and FIG. 2). 3 ・ Figure 5) can be taken.

  In a state in which the image forming housing 42 is moved to a predetermined mounting position, four positioning pins 45 (FIG. 9) provided to protrude rearward on the image forming housing 42 side are provided on the apparatus main body A side. Are fitted in the four positioning holes 46 (FIG. 10). As a result, the mounting position accuracy of the image forming housing 42 in the apparatus main body A is ensured, and the cartridges PY, PM, PC, and PK are mounted in the cartridge storage unit 3 in the apparatus main body A at positions where image formation is possible. It is kept in the state that was done.

  When replacing the cartridge P, the closed door 2 is opened (FIG. 5). In this embodiment, in conjunction with the opening and turning of the door 2, the intermediate transfer belt devices 15 and 21 are lifted and turned upward by a predetermined angle around the support shaft 21a (FIGS. 2 and 3). It is held in its pivot position. Although the interlocking mechanism between the door 2 and the intermediate transfer belt devices 15 and 21 is omitted in the drawing, a cam mechanism, a link mechanism, and the like that move the intermediate transfer belt devices 15 and 21 up and down in conjunction with the opening and closing rotation of the door 2. It can be configured appropriately. By the upward rotation of the intermediate transfer belt devices 15 and 21, the belt 16 is held in a separated state from the state in which the belt 16 is in contact with the upper surface of the drum 4 of each cartridge P. In this embodiment, an interlocking mechanism that rotates and holds the intermediate transfer belt devices 15 and 21 upward in conjunction with the opening and rotation of the door 2 causes the intermediate transfer belt devices 15 and 21 to move from the drum 4. It is a separation means for separating.

  Therefore, the user grasps an appropriate position of the image forming case 42 exposed from the opening 41, and slides the image forming case 42 horizontally from the apparatus main body A by the rail members 44L and 44R. Due to the forward movement of the image forming housing 42, the positioning pin 45 comes out of the positioning hole 46 (positioning release). Further, the coupling of the drive input section on the cartridge P side to the drive output sections 47 and 48 (FIG. 10) on the apparatus body A side is released (drive release). Further, the continuity of the power receiving system on the cartridge P side with respect to the power feeding system on the apparatus main body A side is cut off (power supply cancellation). Then, as shown in FIGS. 6 and 7, the image forming housing 42 passes through the opening 41, and the cartridge P is fully pulled out to a predetermined drawing position where it can be attached and detached outside the apparatus main body A. The laser exposure device 9 disposed on the lower side of the cartridge P and the intermediate transfer belt devices 15 and 21 disposed on the upper side remain in the apparatus main body A and are supported. Since the intermediate transfer belt devices 15 and 21 are moved to a state in which the belt 16 is separated from the drum 4 of the cartridge P, rubbing between the drum 4 and the belt 16 occurs during the drawing movement of the image forming housing 42. Absent. Therefore, scratches and memory caused by rubbing between the drum 4 and the belt 16 can be prevented.

  By pulling out the image forming housing 42, the entire cartridges PY, PM, PC, and PK held in the image forming housing 42 pass through the opening 41 and are exposed to the outside of the apparatus main body A. Is released. When the image forming housing 42 is pulled out by a predetermined sufficient amount, further pulling out is prevented by stopper portions (not shown) of the rail members 44L and 44R. Further, the state in which the image forming housing 42 is pulled out horizontally to a predetermined drawing position is stably maintained by the rail members 44L and 44R.

  The belt cleaner device 24 and the waste toner storage device 39 communicate with each other through a communication unit (not shown) when the image forming housing 42 is located at the mounting position. The connecting portion is separated by pulling out the image forming housing 42. At this time, the connecting portion on the belt cleaner device 24 side is closed by the shutter, and leakage of waste toner is prevented. The shutter is opened when the image forming housing 42 is located at the mounting position, and the communication portion of the belt cleaner device 24 communicates with the communication portion of the waste toner storage device 39.

  The image forming housing 42 detachably supports the individual cartridges P from above at the drawing position. Therefore, the cartridge P to be replaced is grasped and lifted upward and removed from the image forming housing 42. Then, a new cartridge P is mounted and supported on the image forming housing 42 from above.

  In conjunction with the movement of the cartridge in the direction in which the cartridge P is removed from the image forming housing 42, first and second shutters, which will be described later, close to operate, and the first toner passes the toner from the toner supply device 34 to the cartridge P. The transfer part 36 is shielded. In addition, a third shutter, which will be described later, is also closed, and the second toner transfer unit 37 that transfers the waste toner from the cartridge P to the waste toner conveying device 38 is shielded. Conversely, in conjunction with the movement of the cartridge P in the mounting direction of the cartridge P in the image forming housing 42, the first and second shutters open to pass the toner from the toner supply device 34 to the cartridge P. The first toner transfer unit 36 is opened. In addition, the third shutter is also opened, and the second toner transfer unit 37 that transfers the waste toner from the cartridge P to the waste toner conveying device 38 is opened.

  As described above, when the image forming housing 42 is pulled out to the drawing position and the cartridge to be replaced is replaced, the image forming housing 42 is moved further into the apparatus main body A by the stopper portion (not shown). Push it in enough until it is blocked. In this state, the positioning pin 45 on the image forming housing 42 side is fitted into the positioning hole 46 on the apparatus main body A side. As a result, the image forming housing 42 is positioned in the apparatus main body A, and the cartridges PY, PM, PC, and PK are held in the cartridge storage portion 3 in the apparatus main body A in a state where they are mounted at positions where image formation is possible. Is done. Further, the drive input section on the cartridge P side is coupled to the drive output sections 47 and 48 (FIG. 10) on the apparatus main body A side. Further, the power receiving system of each cartridge P becomes conductive with respect to the power feeding system on the apparatus main body A side. Since the intermediate transfer belt unit 15 is moved to a position where the belt 16 is separated from the drum 4 of each cartridge P, rubbing between the drum 4 and the belt 16 occurs during the pushing movement of the image forming housing 42. Absent. Therefore, scratches and memory caused by rubbing between the drum 4 and the belt 16 can be prevented.

  Then, the door 2 is closed. In conjunction with the closing and turning of the door 2, the intermediate transfer belt devices 15 and 21 are turned and lowered about the support shaft 21a. As a result, the belt 16 returns to the state in contact with the upper surface of the drum 4 of the cartridges PY, PM, PC, and PK.

"cartridge"
11, 12 and 13 are external perspective views of the cartridge P in different viewing directions. The cartridge P is an assembly in which the axial direction HH of the drum 4 is the front-rear direction and the front-rear direction is the longitudinal direction.

  The drum 4 is rotatably supported between a front bearing portion 51 and a rear bearing portion 52 respectively disposed on a front frame plate portion (front plate) 8b and a rear frame plate portion (rear plate) 8c of the cartridge frame body 8. Arranged. The rear bearing portion 52 is provided with a first coupling fitting portion 53 as a drum drive input portion. The drum fitting output 53 (FIG. 10) on the apparatus main body A side is coupled to the coupling fitting portion 53 so that driving input is made. Thereby, the drum 4 is driven. The rear frame plate portion 8c of the cartridge frame 8 is provided with a second coupling fitting portion 54 as a developing drive input portion. A drive input is made by the development drive output section 48 (FIG. 10) on the apparatus body A side being coupled to the coupling fitting section 54. As a result, the developing roller 6d and the screw shafts 6b and 6c of the developing device 6 are driven.

  The cartridge P is provided with an electrical contact for bias application (not shown) for the charging roller 5 and an electrical contact for bias application (not shown) for the developing roller 6d. These electrical contacts are in electrical contact with intermediate electrical contacts (not shown) provided on the image forming housing 42 side in a state where the cartridge P is mounted on the image forming housing 42. The intermediate electrical contact is in electrical contact with a body electrical contact (not shown) on the apparatus body A side in a state where the image forming housing 42 is mounted in the apparatus body A. As a result, the power feeding system on the apparatus main body A side and the power receiving system on the cartridge P side are connected.

  In the above cartridge P, the rear frame plate portion 8c side provided with the coupling fitting portions 53 and 54 is the drive side, and the opposite front frame plate portion 8b side is the non-drive side.

  Further, a first toner passing portion 36 between the developing container 6a and the toner replenishing device 34 is formed on the non-driving side upper surface portion of the cartridge frame 8 corresponding to the non-driving side upper surface portion of the developing container 6a of the cartridge P. An opening 55 on the cartridge side is disposed. A first shutter 56 for opening and closing the opening 55 is provided.

  The first shutter 56 is disposed so as to be slidable in the lateral direction of the cartridge along the upper surface of the cartridge frame 8, and is constantly urged to move in a direction to close the opening 55 by an urging member (spring or the like) 57. ing. The closing direction of the first shutter 56 is the mounting (insertion) direction of the cartridge P with respect to the image forming housing 42, and the opening direction is the opposite direction. In a free state in which the cartridge P is removed from the image forming housing 42, the first shutter 56 moves in the closing direction until it is received by the abutting member 58 and blocks the opening 55.

  In addition, the front frame plate portion 8b portion of the cartridge frame 8 corresponding to the non-driving side end portion of the cleaner container 7b of the drum cleaner device 7 has a rotating cylinder type first provided with an opening 59a in a part of the peripheral surface. 3 shutters (waste toner shutters) 59 are provided. The third shutter 59 is held in a rotational angle posture in which the opening 59a faces upward when the cartridge P is detached from the image forming housing 42. In the present embodiment, the third shutter 59 is in a shutter-closed state where the opening 59a faces upward, and the opening 59a faces upward, so that waste toner leaks from the cleaner container 7b. Is blocked.

《Image housing》
FIG. 14 is an external perspective view of a single image forming housing. The image forming housing 42 is made of synthetic resin, sheet metal, or composite material, and accommodates four cartridges PY, PM, PC, and PK by connecting the front and rear, left and right frame plate portions 42a, 42b, 42c, and 42d. The frame part which can do is comprised.

  Four recesses 60 (first positioning portions) for receiving the front bearing portions 51 (first positioned portions) of the respective cartridges P are formed in the front frame plate portion 42a. Further, a hole 61 for arranging the waste toner conveying device 38 is formed.

  Four recesses 62 (second positioning portions) for receiving the rear bearing portions 52 (second positioned portions) of the cartridges P are formed in the rear frame plate portion 42b. Further, four holes 63 through which the four development drive output units 48 (FIG. 10) on the apparatus main body A side enter and exit are formed.

  As shown in FIGS. 15 and 16, a toner cartridge TY / TM / TC / TK, a toner supply device 34, a waste toner conveying device 38, and a waste toner collecting device 39 are disposed outside the front frame plate portion 42a. . Four toner supply pipe portions 64 for the respective cartridges P protrude from the inside of the front frame plate portion 42a. Each pipe portion 64 has an opening 65 (FIGS. 21 and 22) on the toner supply device side that constitutes a first toner transfer portion 36 that transfers toner from the toner supply device 34 to the cartridge P, and the opening 65. A second shutter 71 for opening and closing is provided. In addition, inside the front frame plate portion 42a, four upward openings 67 on the side of the waste toner conveying device 38 constituting the second toner passing portion 37 for passing the waste toner from each cartridge P to the waste toner conveying device 38. Is arranged.

  In addition, first and second guide rails 68 and 69 for attaching and detaching the cartridge P to the image forming housing 42 are disposed inside the front frame plate portion 42a and inside the rear frame plate portion 42a, respectively. ing. The first and second guide rails 68 and 69 are arranged in four sets corresponding to the first to fourth cartridges PY, PM, PC, and PK.

<Attachment / detachment of cartridge to / from image forming housing and shutter opening / closing interlock mechanism>
In the present embodiment, the first and second guide rails 66 and 67 are disposed so as to be inclined downward to the left when the image forming housing 42 is viewed from the front side. The cartridge P is attached to the image forming housing 42 in the following manner. That is, the cleaner container 7d side of the cartridge P is grasped. The cartridge P is tilted to the left in accordance with the inclination of the guide rails 66 and 67, as shown in FIGS. insert. Then, the lower surface portions of the non-drive side and the drive side of the cartridge P are placed on the first and second guide rails 66 and 67, respectively. Further, the cartridge P is inserted into the image forming housing 42 while being slid downward along the guide rails 66 and 67. Finally, the front bearing portion 51 and the rear bearing portion 52 are received by being fitted and engaged with the recesses 60 and 62 on the front frame plate portion 42a side and the rear frame plate portion 42b side of the image forming housing 42, respectively. . Thus, the cartridge P is supported by the guide rails 66 and 67 and the recesses 60 and 62 and is mounted in a state of being positioned with respect to the image forming housing 42.

  As described above, the first shutter 56 of the cartridge P is held in a state where the upward opening 55 is closed by the urging member 57 in the free state in which the cartridge P is detached from the image forming housing 42. Yes. Further, the third shutter 59 is also held in a shutter-closed rotation angle posture in which the opening 59a faces upward.

  The opening 65 (FIGS. 21 and 22) of the toner supply pipe portion 64 of each toner supply device 34 faces downward. The second shutter 71 for opening and closing the opening 65 is disposed so as to be slidable in the left-right direction along the opening surface of the opening 65, and the opening 65 is opened by a biasing member (spring or the like) 72. Always urged to move in the closing direction. The closing direction of the second shutter 71 is opposite to the mounting direction of the cartridge P with respect to the image forming housing 42, and the opening direction is the opposite direction. In a state where the cartridge P is detached from the image forming housing 42, the second shutter 71 moves in the closing direction until it is received by an abutting member (not shown) to shield the opening 65.

  FIG. 21 shows the middle of the insertion movement of the cartridge P with respect to the image forming housing 42. In the middle of this insertion movement, both the first shutter 56 and the second shutter 71 are still in the state in which the openings 55 and 65 are closed.

  When the cartridge P is further inserted, the upper bent edge portion 56a of the first shutter 56 comes into contact with and is received by the abutting portion 64a of the toner supply pipe portion 64. Further, the abutting portion 8 d of the cartridge P abuts on the downward bent edge portion 71 a of the second shutter 71. When the cartridge P is further inserted, the first shutter 56 is received by the abutting portion 64a of the toner supply pipe portion 64. Therefore, the biasing member 57 is attached to the cartridge P to be inserted and moved. It moves in the opening direction relative to the forces. Further, the second shutter 71 is pushed by the cartridge P moving in the insertion direction and moves in the opening direction together with the cartridge P against the urging force of the urging member 72. Thus, in conjunction with the insertion movement of the cartridge P, the first and second shutters 56 and 71 open each other, and the opening 55 corresponds to the opening 65. Then, when the cartridge P is finally positioned and mounted with respect to the image forming housing 42, both the first and second shutters 56 and 71 are fully opened as shown in FIG. , The opening 55 matches the opening 65. That is, the opening 55 on the cartridge side corresponding to the opening 55 on the toner replenishing device 34 side corresponding to the first toner passing portion 36 is in an open state.

  Further, the third shutter 59 is still held in the shutter-closed rotation angle posture with the opening 59a facing upward in the middle of the insertion movement of the cartridge P with respect to the image forming housing 42 (FIG. 22). When the cartridge P is further inserted, the pinion gear 59b provided concentrically with the third shutter 59 meshes with the rack gear portion 66a provided on the first guide rail 66. When the cartridge P is further inserted, the pinion gear 59b rotates counterclockwise in FIG. 22 by meshing with the rack gear portion 66a. That is, the third shutter 59 rotates counterclockwise in conjunction with the movement of the cartridge P in the mounting direction. Then, in a state where the cartridge P is finally positioned and mounted with respect to the image forming housing 42, the third shutter 59 rotates approximately 180 °. Due to the rotation of the third shutter 59, the opening 59 a faces downward and matches the upward opening 67 on the waste toner conveyance device 38 side. In the present embodiment, the third shutter 59 is in the shutter open state with the rotation angle posture in which the opening 59a faces downward. In other words, the cartridge-side opening 59a constituting the second toner transfer portion 37 and the waste toner conveying device 38-side opening 67 correspond to each other, and the second toner transfer portion 37 is opened.

  The above-described movement operation of the first and second shutters 56 and 71 from the closed position to the open position and the rotation operation of the third shutter 59 from the closed position to the open position are the image forming housing 42 of the cartridge P. This is done in the final stage of the movement process.

  On the other hand, the removal of the cartridge P attached to the image forming housing 42 is performed by grasping the cartridge P on the cleaner container 7d side and moving upward along the guide rails 66 and 67 in the direction opposite to the cartridge mounting direction. It is slid and removed from the image forming housing 42.

  As the cartridge P is removed, the first shutter 56 received by the abutting portion 64a of the toner supply pipe portion 64 is urged by the urging force of the urging member 57 against the cartridge P moving in the removal direction. Move relatively in the closing direction. The second shutter 71 also moves in the closing direction by the urging force of the urging member 72 together with the cartridge P to be removed and moved. When the cartridge P is further removed and moved, the first shutter 56 is closed and moved by the urging force of the urging member 72 until it is received by the abutting member 58 to conceal the opening 55. The second shutter 71 is also closed and moved by the urging force of the urging member 72 until the second shutter 71 is received by an abutting member (not shown) to conceal the opening 65. That is, in conjunction with the movement of the cartridge P in the removal direction, the cartridge-side opening 55 and the toner replenishing device 34-side opening 65 constituting the first toner transfer section 36 are respectively connected to the first and second openings. Concealed by shutters 56 and 71. This is the concealment state of the first toner transfer unit 36.

  Further, the third shutter 59 rotates back in the clockwise direction opposite to the cartridge mounting movement in FIG. 23 when the cartridge P is removed and the pinion gear 59b is engaged with the rack gear 66a. That is, the third shutter 59 rotates in the clockwise direction in conjunction with the movement of the cartridge P in the removal direction, so that the shutter is opened from the lower side of the opening to the closed state of the upper side of the opening, and the pinion gear 59b is moved to the rack gear portion 66a. Deviate from. As a result, the cartridge-side opening 59a constituting the second toner transfer portion 37 faces upward, and moves away from the opening 67 on the waste toner conveying device 38 side. This is the concealment state of the second toner transfer unit 37.

  The movement operation of the first and second shutters 56 and 71 from the open position to the closed position and the rotation operation of the third shutter 59 from the open position to the closed position are the image forming housing 42 of the cartridge P. This is done in the initial stage of the removal movement process.

  As described above, the apparatus main body A has a drawer position where the cartridge P is supported and the cartridge P can be attached / detached outside the apparatus main body A, and a mounting position for mounting the cartridge P inside the apparatus main body A. An image forming housing 42 as a moving member to be obtained is provided. A toner cartridge T, a toner supply device 34, a waste toner transport device 38, and a waste toner collection device 39 for the cartridge P are supported on the image forming housing 42. Then, in a state where the image forming housing 42 is pulled out to the outside of the apparatus main body A, the first toner transfer unit 36 and the second toner transfer unit 37 are opened and shielded. Accordingly, the first and second shutters 56 and 71 in the first toner transfer unit 36 and the third shutter 59 in the second toner transfer unit 37 are opened and closed on the laser exposure device 9 in the apparatus main body A. It is possible to prevent the scattered toner from dropping due to the operation and to prevent image defects.

  In addition, the opening and closing operations of the first and second shutters 56 and 71 in the first toner transfer unit 36 and the third shutter 59 in the second toner transfer unit 37 are performed by attaching and detaching the cartridge P with respect to the image forming housing 42. It is performed in conjunction with. By doing so, the first and second shutters 56 and 71 and the third shutter 59 are opened and closed only at the timing of cartridge replacement with respect to the image forming housing 42, so that the number of times of opening and closing the shutter can be drastically reduced, and the toner scatters. Is very low.

[Example 2]
The present embodiment will be described with reference to FIGS. Constituent members / portions common to the image forming apparatus according to the first exemplary embodiment are denoted by the same reference numerals, and description thereof is omitted.

  As in the first embodiment, the image forming housing 42 that is a moving member supports a cartridge P, a toner cartridge T, a toner supply device 34, a waste toner conveying device 38, and a waste toner collecting device 39. In this embodiment, intermediate transfer belt devices 15 and 21 including a belt cleaner device 24 are further supported on the image forming housing 42 as a process cartridge replacement cover. Accordingly, when the door 2 is opened and the image forming housing 42 is pulled out from the inside of the apparatus main body A to the front outer side by the rail members 44L and 44R, the intermediate transfer belt apparatuses 15 and 21 including the belt cleaner device 24 are also included in the apparatus main body A. Is pulled out to the outside (FIG. 23).

  The intermediate transfer belt devices 15 and 21 are arranged on the upper side of the cartridges PY, PM, PC, and PK supported by the image forming housing 42, and center on the left support shaft 21a with respect to the image forming housing 42. The cartridge P is supported so as to be openable and closable (can be turned upside down). Then, the intermediate transfer belt devices 15 and 21 are arranged in the state shown in FIG. It is possible to switch to a closed position that has been pushed down. Further, as shown in FIG. 24, it is possible to switch to an open posture in which a predetermined angle is raised. H1 is a rotation direction to the closing posture of the intermediate transfer belt devices 15 and 21, and G1 is a rotation direction to the opening posture. A handle 21 b is provided on the right side of the upper surface of the transfer frame 21 for opening and closing the intermediate transfer belt devices 15 and 21. When the intermediate transfer belt devices 15 and 21 are changed to the closed position, the lower surface of the belt 16 of the intermediate transfer belt unit 15 is in contact with the upper surface of the drum 4 of each cartridge P. Further, when the intermediate transfer belt devices 15 and 21 are opened and rotated at a predetermined angle, the opening posture is stably held by a stopper mechanism (not shown). When the intermediate transfer belt devices 15 and 21 are changed to the open posture, the upper portion of each cartridge P is largely opened. Thereby, similarly to the case of the first embodiment, the replacement work of each cartridge P with respect to the image forming housing 42 can be performed. When the cartridge to be replaced is replaced, the stopper mechanism is released, and the intermediate transfer belt devices 15 and 21 are changed to the closed position shown in FIG. Then, the image forming housing 42 is sufficiently pushed into the apparatus main body A and moved to close the door 2.

  In the present embodiment, in conjunction with the opening / closing rotation of the intermediate transfer belt device 15, 21, the second toner on the toner replenishing device 34 side in the first toner delivery unit 36 that delivers toner from the toner replenishing device 34 to the cartridge P is used. The shutter 71 is opened and closed. That is, in this embodiment, when the intermediate transfer belt device 15/21 is rotated in the G1 direction and the H1 direction, the gear 73 is coaxially fixed to the support shaft (rotation shaft) 21a of the intermediate transfer belt device 15/21. Through the gear train 74, the opening / closing rack 75 moves in the J1 and K1 directions. The open / close rack 75 moves in the J1 direction in conjunction with the rotation in the G1 direction when the intermediate transfer belt devices 15 and 21 are changed from the closed posture to the open posture. Conversely, the open / close rack 75 moves in the K1 direction in conjunction with the rotation in the H1 direction when the intermediate transfer belt device 15 or 21 is changed from the open position to the closed position.

  Therefore, when the intermediate transfer belt device 15 or 21 is opened and the cartridge P is removed from the image forming housing 42, the open / close rack 75 moves in the J1 direction. In conjunction with the movement of the opening / closing rack 75 in the J1 direction, the shutter moving member 77 and the second shutter 71 move in the L2 direction (shutter closing direction) via the gear 76 connected to the opening / closing rack 75 (FIG. 26). ). As a result, the first toner transfer section 36 from the toner supply device 34 to the cartridge P is blocked. Then, the cartridge P can be removed by extracting the cartridge P from the image forming housing 42 in the S1 direction. Conversely, the cartridge P is inserted and set in the image forming case 42 in the T1 direction, and the intermediate transfer belt devices 15 and 21 are switched to the closed posture. Then, the open / close rack 75 moves in the K1 direction, the shutter moving member 77 and the second shutter 71 move in the L1 direction (shutter opening direction), and the first toner transfer unit 36 from the toner supply device 34 to the cartridge P. Is opened and toner can be supplied (FIG. 27).

  Further, in this embodiment, the third shutter 59 and the fourth shutter 79 in the second toner transfer section 37 are interlocked with the rotation of the intermediate transfer belt devices 15 and 21 in the G1 direction and the H1 direction. Open and close. The third shutter 59 is a waste toner shutter that opens and closes the opening of the waste toner outlet portion on the cartridge P side, and the fourth shutter 79 is the opening 67 (FIG. 16) of the waste toner inlet portion on the waste toner conveying device 38 side. A waste toner shutter that opens and closes.

  The third and fourth shutters 59 and 79 and the opening / closing mechanism thereof will be described with reference to FIGS. Referring to FIGS. 28 to 30, the gear portion 78 provided on the open / close rack 75 and the gear 81 on the rotation shaft 80 of the fourth shutter 79 on the waste toner conveying device 38 side mesh with each other, and the fourth shutter 79 is engaged. Rotate. Then, in a state where the cartridge P is mounted in the image forming housing 42, the third shutter 59 (FIG. 31) on the cartridge P side of the fourth shutter 79 is the V1 portion as shown in FIG. Join with. As a result, the fourth shutter 79 on the waste toner conveying device 38 side and the cartridge P side on the second side are disposed via the open / close rack 75 in conjunction with the rotation of the intermediate transfer belt devices 15 and 21 in the G1 direction and the H1 direction. The three shutters 59 can be opened and closed together. That is, when the intermediate transfer belt devices 15 and 21 are opened, the third and fourth shutters 59 and 79 are closed and rotated in conjunction with this, and the second toner transfer portion 37 is shielded (see FIG. 32 (a)). Then, the cartridge P is removed from the image forming housing 42 in a state where the second toner transfer portion 37 is shielded. Further, the cartridge P is mounted on the image forming housing 42 in a state where the second toner transfer portion 37 is shielded. After that, the intermediate transfer belt devices 15 and 21 are closed, and in conjunction therewith, the third and fourth shutters 59 and 79 are opened and rotated to open the second toner transfer portion 37. ((B) of FIG. 32). This makes it possible to treat waste toner. In FIGS. 29 and 30, reference numeral 38a denotes a screw shaft or a flexible rotating coil member which is disposed in the waste toner conveying device 38 and conveys toner. In FIG. 32, 79a indicates an opening on the fourth shutter 79 side, and ta indicates waste toner in the cleaner container 7b.

  In this embodiment, the intermediate transfer belt devices 15 and 21 are used as process cartridge replacement covers, and the first and second toner transfer portions 36 and 37 are interlocked with the opening and closing rotation of the intermediate transfer belt devices 15 and 21. The shutters 71, 79 and 59 were opened and closed. As the process cartridge replacement cover, an object other than the intermediate transfer belt device 15 or 21 that moves when accessed may be used.

  As described above, the toner shutter and the waste toner shutter are opened and closed in conjunction with the access of the cartridge, and the toner or waste toner transfer section is shut off and opened, so that the image forming apparatus main body is scattered. Image defects due to toner drop do not occur.

  In this embodiment, since the shutter is opened and closed after the cartridge P is set in the image forming housing 42, the amount of scattered toner due to the opening and closing of the shutter is very small.

  Further, since the shutter is opened / closed only when the cartridge is replaced, an image forming apparatus with few shutters opened / closed and almost no scattered toner can be realized.

[Other matters]
1) The cartridge P may not be provided with the drum cleaner 7, and the waste toner on the tram 4 may be transferred to the intermediate transfer belt 16 and collected by the belt cleaner 24.

  2) It is also possible to adopt a cleaner-less cartridge configuration in which the transfer residual toner on the drum 4 is simultaneously collected by the developing device 6 and the drum cleaner device 7 is omitted.

  3) Although the electrophotographic image forming apparatus shown in the embodiment uses four cartridges, the number of cartridges is not limited to four. Arbitrary plural or one may be sufficient.

  4) Instead of the intermediate transfer system, it is also possible to adopt an apparatus configuration that directly transfers the toner image formed on the drum 4 to a recording material that is a recording medium.

The perspective view of the electrophotographic image forming apparatus of an Example Longitudinal front schematic view of this image forming apparatus Partial enlarged view of FIG. Development schematic diagram of toner supply system for cartridge developing device and recovery system for waste toner from drum cleaner Perspective view of the image forming apparatus with the front door opened 1 is a perspective view of an image forming apparatus in a state where an image forming housing is pulled out (part 1). The perspective view of the image forming apparatus in the state where the image forming housing is pulled out (Part 2) A perspective view of the image forming housing supporting the cartridge, the toner cartridge, the waste toner conveying device, and the waste toner collecting device as seen from the front side A perspective view of the image forming housing supporting the cartridge, the toner cartridge, the waste toner conveying device, and the waste toner collecting device as seen from the rear side. A perspective view of the image forming apparatus with the front door opened and the image forming housing removed Perspective view of cartridge (Part 1) Perspective view of cartridge (2) Perspective view of cartridge (Part 3) Perspective view of a single image forming housing that does not support the cartridge, toner cartridge, waste toner conveying device, and waste toner collecting device A perspective view of the image forming housing supporting the toner cartridge, the waste toner conveying device, and the waste toner collecting device as seen from the front side. A perspective view of the image forming housing supporting the toner cartridge, the waste toner conveying device, and the waste toner collecting device as seen from the rear side. The figure which shows the attachment point of the cartridge (the 1) Diagram showing cartridge installation procedure (Part 2) Diagram showing the cartridge installation procedure (Part 3) Diagram showing how to install cartridge (Part 4) Diagram showing how to install cartridge (Part 5) Diagram showing how to install cartridge (Part 6) FIG. 9 is a perspective view of the image forming apparatus according to the second embodiment in a state where an image forming housing is pulled out. Further, a perspective view of the intermediate transfer belt device in an opened state Enlarged perspective view of the main part with the intermediate transfer belt device opened Explanatory drawing of the interlocking mechanism of the opening and closing of the intermediate transfer belt device and the second shutter (part 1) Explanatory drawing of the interlocking mechanism of the opening and closing of the intermediate transfer belt device and the second shutter (part 2) Explanatory drawing of the 4th shutter Explanatory drawing of the interlocking mechanism of the opening and closing of the intermediate transfer belt device and the fourth shutter (part 1) Explanatory drawing of the interlocking mechanism of the opening and closing of the intermediate transfer belt device and the fourth shutter (part 2) Partial perspective view of the third shutter arrangement side of the cartridge Combined diagram of fourth shutter and third shutter

Explanation of symbols

  1 .... Electrophotographic image forming apparatus, A ... Device body, B ... Image reading device, C1 to C5 ... Paper feeding unit, P (PY / PM / PC / PK) ... Process cartridge, 4 .... Electronic Photosensitive drum, 5 .... Charging roller, 6 .... Developing device, 7 .... Drum cleaner device, 9 .... Image exposure device (laser exposure device), 15 .... Intermediate transfer belt unit, T (TY.TM.TC) .. TK) .. toner cartridge 34..toner replenishing device 38..waste toner transport device 39..waste toner collecting device 42..imaging housing (moving member) 36..first toner , Second toner transfer unit, 56, first shutter, 71, second shutter, 59, third shutter, 79, fourth shutter

Claims (12)

An electrophotographic process cartridge having an electrophotographic photosensitive drum and at least developing means for developing a latent image formed on the electrophotographic photosensitive drum with toner as process means acting on the electrophotographic photosensitive drum. In an electrophotographic image forming apparatus that detachably attaches to an apparatus main body of an image forming apparatus and forms an image on a recording medium.
An opening through which the process cartridge is inserted in order to insert the process cartridge into the inside of the apparatus main body and to remove the process cartridge from the inside of the apparatus main body;
A rail member is slidably held, and supports the process cartridge and a toner replenishing device that replenishes toner to the process cartridge. The process cartridge passes through the opening and is attached to the main body of the apparatus. A movable member capable of taking a drawer position that can be attached and detached on the outside, and a mounting position for mounting the process cartridge inside the apparatus main body;
A first toner transfer unit that transfers toner from the toner supply device to the process cartridge;
A first shutter for opening and closing an opening provided in the process cartridge, which constitutes the first toner transfer section, in order to shield and open the first toner transfer section (36); A second shutter for opening and closing an opening provided in the replenishing device;
And the first shutter and the second shutter are closed when the moving member is pulled out to the pulling position and the process cartridge is replaced, thereby shielding the first toner passing portion. The electrophotographic image forming apparatus, wherein the first shutter and the second shutter are opened to open the first toner transfer unit.   The image exposure apparatus for the electrophotographic photosensitive drum is located below the process cartridge supported by the moving member in a state where the moving member is located at the mounting position. 2. The electrophotographic image forming apparatus according to 1.   The electrophotographic image forming apparatus according to claim 1, wherein the moving member supports a plurality of process cartridges.   The plurality of process cartridges contains a process cartridge containing black toner, a process cartridge containing cyan toner, a process cartridge containing magenta toner, and a yellow toner. The electrophotographic image forming apparatus according to claim 3, wherein the electrophotographic image forming apparatus is a process cartridge.   In the state where the moving member is located at the mounting position, the electrophotographic photosensitive drum is formed on the electrophotographic photosensitive drum in contact with the electrophotographic photosensitive drum above the process cartridge supported by the moving member. There is an intermediate transfer belt device for transferring a toner image, and has a separating means for separating the intermediate transfer belt device from the electrophotographic photosensitive drum, and the intermediate transfer belt device is separated from the electrophotographic photosensitive drum. 5. The electrophotographic image forming apparatus according to claim 1, wherein in the state, the moving member is pulled out to the drawing position or moved to the mounting position. 6.   The first shutter and the second shutter are closed in conjunction with movement of the process cartridge in the removal direction from the moving member when the moving member is pulled out to the drawing position. 6. The electrophotographic image forming apparatus according to claim 1, wherein the electrophotographic image forming apparatus opens in conjunction with movement of the moving member in the mounting direction. The process cartridge has a cleaning means for removing waste toner from the electrophotographic photosensitive drum,
The moving member supports a waste toner transport device and a waste toner collection device that stores waste toner transported by the waste toner transport device,
A second toner transfer unit that transfers waste toner from the process cartridge to the waste toner conveying device;
A third shutter for opening and closing an opening provided in the process cartridge, which constitutes the second toner transfer portion, in order to shield and open the second toner transfer portion;
When the moving member is pulled out to the drawing position and the process cartridge is replaced, the third shutter closes and the second toner passing portion is shielded, or the third 7. The electrophotographic image forming apparatus according to claim 1, wherein the shutter is opened to open the second toner transfer portion. 8.   The third shutter closes in conjunction with the movement of the process cartridge in the removal direction from the moving member when the moving member is pulled out to the drawing position, and the process shutter is attached to the moving member. The electrophotographic image forming apparatus according to claim 7, wherein the electrophotographic image forming apparatus opens in conjunction with movement in a direction. The process cartridge has a cleaning means for removing waste toner from the electrophotographic photosensitive drum,
The moving member supports a waste toner transport device and a waste toner collection device that stores waste toner transported by the waste toner transport device,
A second toner transfer unit that transfers waste toner from the process cartridge to the waste toner conveying device;
A third shutter for opening and closing an opening provided in the process cartridge, which constitutes the second toner transfer portion, so as to shield and open the second toner transfer portion; and the waste toner transport device A fourth shutter for opening and closing the opening provided in
And when the process cartridge is replaced when the moving member is pulled out to the pull-out position, the third shutter and the fourth shutter are closed to block the second toner passing portion. The electrophotographic image according to claim 1, wherein the third shutter and the fourth shutter are opened to open the second toner passing portion. Forming equipment.   The third shutter and the fourth shutter are closed in conjunction with the movement of the process cartridge in the removal direction from the moving member when the moving member is pulled out to the drawing position. The electrophotographic image forming apparatus according to claim 9, wherein the electrophotographic image forming apparatus performs an opening operation in conjunction with a movement of the moving member in a mounting direction.   The process cartridge replacement cover is opened and closed. The moving member is pulled out to the drawing position, and the third and fourth shutters are opened and closed in conjunction with opening and closing of the process cartridge replacement cover. 11. The process cartridge is attached to and detached from the moving member after the second toner transfer portion is blocked or opened by opening and closing the third and fourth shutters. Electrophotographic image forming apparatus.   The toner image formed on the electrophotographic photosensitive drum while in contact with the electrophotographic photosensitive drum when the process cartridge replacement cover is supported by the moving member so as to be openable and closable. The electrophotographic image forming apparatus according to claim 11, wherein the electrophotographic image forming apparatus is an intermediate transfer belt apparatus that transfers the toner.

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