JP3931961B2 - Image forming apparatus, process cartridge and developing device used therefor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus such as a copying machine or a printer. In particular, in a method of visualizing a latent image on an image carrier with a developer, it is possible to replenish the developer and collect the waste developer. And an image forming apparatus, a process cartridge used in the image forming apparatus, and a developing device.
[0002]
[Prior art]
Conventionally, as an example of this type of image forming apparatus, for example, an electrophotographic system, a latent image is formed on an image carrier such as a photosensitive drum by scanning light, for example, and a visible image is formed by a developer. Generally, after transfer (development), the image is transferred to a sheet such as paper.
At this time, for example, when the two-component development method is used, the toner or the toner and the carrier are periodically replenished as the toner is consumed (for example, Japanese Patent Laid-Open Nos. 9-185234 and 8-15971). In addition, if the developer is circulated for a long time in the developing device, the characteristics of the developer (such as the chargeability of the carrier) deteriorate, so this kind of deteriorated developer is recovered. (For example, Japanese Patent Laid-Open No. 2-6978).
[0003]
[Problems to be solved by the invention]
By the way, among the prior arts of this type, for example, in the former prior art, the toner can be replenished, but the waste developer cannot be recovered.
In this regard, in the latter prior art (for example, Japanese Patent Laid-Open No. 2-6978), it may be possible to collect waste developer and supply toner in the same casing.
However, for example, since the waste developer in the developing device is heavy with a mixture of carriers, it is extremely difficult to lift and transport the waste developer to the same housing where toner is supplied.
For example, a method of lifting and transporting the waste developer using an endless belt (for example, JP-A-8-123275) may be effective, but there is a concern that the cost is increased in terms of the complexity of the mechanism and the durability of the belt.
[0004]
In addition, since a latent image is formed by scanning light on the image carrier, it is essential to select a position that does not interfere with the incident position of the scanning light for the layout of the toner supply box and the waste developer recovery box. is there.
For example, in a mode in which a sheet onto which a visible image is transferred on an image carrier is conveyed upward in a substantially vertical direction, a toner replenishment box and waste development on the lower side (corresponding to the downstream side) from the scanning light incident position If the agent recovery box is arranged, for example, when considering a model change in which the toner replenishment amount is to be increased, the amount of the toner replenishment box increases, which affects the position of the sheet tray disposed on the lower side, for example. Thus, not only is the specification change associated with the change in the toner replenishment amount different, but it is difficult to share it, and conversely, a dead space is likely to occur above the scanning light incident position.
[0005]
On the other hand, if a toner replenishment box and a waste developer recovery box are arranged above the scanning light incident position (corresponding to the upstream side), the developing unit of the normal developing device is located more than the incident position of the scanning light. Since it is disposed on the lower side, a replenishment path and a recovery path that communicate between the toner replenishment box and the waste developer recovery box and the developing unit are required.
At this time, both the supply path from the toner supply box and the recovery path from the waste developer recovery box need to be installed in two systems without interfering with each other at a position outside the incident path of the scanning light. Accordingly, a technical problem arises that the longitudinal dimension of the apparatus is increased and the apparatus is unnecessarily enlarged.
[0006]
The present invention has been made to solve the above technical problems, and can easily cope with changes in specifications such as downsizing of the apparatus and developer replenishment amount without causing dead space in the apparatus. The present invention provides an image forming apparatus capable of achieving both a developer replenishing function and a waste developer collecting function, and a process cartridge and a developing device used therefor.
[0007]
[Means for Solving the Problems]
  That is, in the present invention, as shown in FIG. 1, latent image forming means 2 for forming a latent image on an image carrier 1 is used.,Developing device 3 that visualizes the latent image formed on image carrier 1 with a developer.And a transfer device 10 for transferring the visible image formed on the image carrier 1 to the sheet S, an image forming engine provided in the device main body 7, and an upper portion of the device main body 7 and the device main body. 7 is provided with a discharge tray 7b having an inclined portion that is lower on the discharge port side from which the sheet S is discharged and becomes higher as the distance from the discharge port increases, and a sheet supply device provided below the image forming engine in the apparatus body 7. The sheet S supplied from the sheet supply device is transported from the lower side to the upper side on one side of the apparatus main body 7 and discharged to the discharge tray 7b through the transfer portion of the transfer device 10.In the image forming apparatus, the developing device 3 includes a developing housing 4 in which a developer is accommodated.Developer can be replenishedDeveloper supply box 5 andThe waste developer in the development housing 4 can be collected.The waste developer recovery boxes 6 are connected to each other,Below the inclined portion of the discharge tray 7bLatent image writing position P on the image carrier 1On the upper side acrossThe developer supply box 5 is disposed, and the latent image writing position PThe developing housing 4 andWaste developer collection box 6Horizontally adjacentInstalledFurther, the developer supply box 5 and the waste developer collection box 6 are configured as one unit with the scanning light path for latent image writing interposed therebetween, and the developer supply box 5 and the waste are disposed with respect to the development housing 4. The developer recovery box 6 can be integrally separated.It is characterized by this.
[0008]
In such technical means, the present case is intended for all image forming apparatuses of a type in which a latent image is visualized by the developing device 3, and is not limited to a monochrome machine, for example, the image carrier 1 The present invention can also be applied to a tandem type color machine arranged in plural.
Further, the developing device 3 can specify any developer as long as it performs developer replenishment and waste developer recovery, and it can be used only as a carrier medium for the supplied toner, including a two-component developer. An embodiment using a magnetic carrier can be selected as appropriate.
Further, the developer supply box 5 includes a wide range of containers for supplying developer (toner, toner + carrier).
Furthermore, the waste developer collection box 6 includes a wide range of containers for collecting waste developer (mainly a deteriorated developer in the developing device 3 but not excluding cleaned waste toner). .
[0009]
  The latent image writing position P is used as a reference when a latent image is formed on the image carrier 1 when the developer supply box 5 and the waste developer collection box 6 block the latent image writing position. Due to not being able to.
  As in this embodiment, the latent image writing position PUpwardDeveloper supply box 5DownIf the waste developer collection box 6 is provided, the developer replenishment function and the waste developer collection function can be made compatible while effectively using the space in the apparatus.
  In particular,Above the latent image writing position PThe reason why the developer replenishment box 5 is disposed is that it is easy to cope with a change in capacity.
[0010]
  In this embodiment, the developer supply box 5 and the waste developer collection box 6 are configured as one unit.ing.
  In this case, a separate waste developer collection box 6 is not provided, and full detection of the waste developer collection box 6 is unnecessary.
  Further, in this type of image forming apparatus, the apparatus main body 7 is detachably mounted, and the image carrier 1 and at least one process unit 9 (9a: for example, charging unit, 9b: for example, cleaning unit) are incorporated. The process cartridge 8 is provided with the developer supply box 5 and the waste developer collection box 6.thingIs preferred.
  According to this aspect, the process cartridge 8 can be attached to and detached from the apparatus main body 7 with both the boxes 5 and 6 included.
[0011]
Furthermore, the developer supply box 5 and the waste developer collection box 6 are preferably detachable from the process cartridge 8.
In this case, the developer replenishment box 5 and the waste developer collection box 6 can be independently replaced, and the process cartridge 8 can be effectively used.
It is also preferable that the image carrier cartridge including at least the image carrier 1 is detachable from the process cartridge 8.
In this case, the image carrier cartridge can be uniquely replaced, and the process cartridge 8 can be effectively used.
Further, it is preferable that the process cartridge 8 is detachable from above by opening the opening / closing cover 7a at the top of the apparatus body 7.
In this case, the detachability of the process cartridge 8 can be improved, and the cost of the apparatus main body 7 can be reduced by sharing the opening / closing cover 7a.
[0012]
  Image forming apparatusIsThe visible image on the image carrier 1 is, for example,Transfer deviceA mode in which the sheet S transferred by the sheet 10 is conveyed from the lower side toward the upper side.AndA developer replenishment box 5 is disposed above the latent image writing position P of the image carrier 1, and at the lower side of the latent image writing position P.Development housing 4 andA waste developer recovery box 6 is provided.It is a thing.
  In this case, it is preferable to dispose the developer supply box 5 above the latent image writing position P in that the degree of freedom in layout of the developer supply box 5 (easy to cope with an increase in capacity) is increased.
  Furthermore, in an aspect provided with a substantially vertical sheet path, a discharge tray 7b for storing discharged sheets may be provided above the developer supply box 5.
  At this time, the dead space below the discharge tray 7 b can be effectively used as the installation space for the developer supply box 5.
[0013]
Further, in a mode in which a substantially vertical sheet path is provided, as a preferable communication structure between the developer supply box 5 and the development housing 4, the supply port of the developer supply box 5 is located above the developer accommodating portion of the development housing 4. The new developer from the developer supply box 5 can be supplied to the developing housing 4 via a supply path at a position deviated from the latent image writing position P on the image carrier 1. An embodiment is mentioned.
Further, in a mode provided with a substantially vertical sheet path, as a preferable communication structure between the waste developer collection box 6 and the development housing 4, the collection port of the waste developer collection box 6 serves as a waste developer of the development housing 4. There is a mode in which the waste developer discharged from the developing housing 4 is displaced upward from the discharge port, and conveyed to the recovery port of the waste developer recovery box 6 positioned above via the rotary transport body. .
Here, as the rotary conveyance body, a rotary fin may be rotatably provided in the ring-shaped fixed frame, and the waste developer may be scooped up by the rotary fin, or a temporary receiving portion may be provided on the ring-shaped rotary member. It may be appropriately selected, for example, by appropriately partitioning and rotating the ring-shaped rotating member itself so that the waste developer accommodated in the temporary receiving portion is rotated.
[0014]
The present invention is not limited to the above-described image forming apparatus, but also covers a process cartridge 8 and a developing device 3 used in the image forming apparatus as shown in FIG.
[0015]
Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
Embodiment 1
FIG. 2 is an explanatory view showing Embodiment 1 of the image forming apparatus according to the present invention.
In FIG. 1, the image forming apparatus includes, for example, an electrophotographic image forming engine 21 in the apparatus main body 20, a sheet supply device 22 below the image forming engine 21 in the apparatus main body 20, and an apparatus main body. 20 is configured as a discharge tray 27, and a sheet S sent from the sheet supply device 22 to the back side (corresponding to the left side in FIG. 2) in the apparatus main body 20 is guided to the image forming engine 21 and the discharge tray 27. The conveyance path 23 is provided in a substantially vertical direction.
[0016]
In the present embodiment, the image forming engine 21 employs, for example, an electrophotographic system, and includes a photosensitive drum 31, a charging device (charging roll in this example) 32 that charges the photosensitive drum 31, and An exposure device 33 such as a laser scanning device for writing an electrostatic latent image (hereinafter referred to as a latent image) on the charged photosensitive drum 31, a developing device 34 for developing the latent image on the photosensitive drum 31, and a photosensitive member. A transfer device (transfer roll in this example) 35 that transfers a visible image (toner image) on the drum 31 to the sheet S and a cleaning device 36 that cleans residual toner on the photosensitive drum 31 are provided.
A registration roll 24 for positioning and conveying the sheet S is provided on the upstream side of the photosensitive drum 31 in the sheet conveying path 23, and a fixing device 25 is provided on the downstream side of the photosensitive drum 31 in the sheet conveying path 23. And a discharge roll 26 is provided immediately before the discharge tray 27.
[0017]
Further, in the present embodiment, most of the devices of the image forming engine 21 are integrally configured as a process cartridge 40.
That is, the process cartridge 40 used in the present embodiment includes the photosensitive drum 31, the charging device 32, the developing device 34, and the cleaning device 36 as shown in FIGS. It is detachably mounted and has a so-called CRU (Customer Replaceable Unit) configuration.
In this example, the photosensitive drum 31, the charging device 32, and the cleaning device 36 integrally form the photosensitive cartridge 41 and are detachably attached to the process cartridge 40.
[0018]
Here, in the photosensitive cartridge 41, the charging device 32 is arranged on the upstream side (corresponding to the upper side in this example) of the latent image writing position P of the photosensitive drum 31 in the cartridge case 411. A cleaning device 36 is disposed on the upstream side.
In this example, the cleaning device 36 includes a part of the cartridge case 411 as a cleaning case 360, a cleaning blade 361 provided at the opening edge of the cleaning case 360 and disposed in contact with the photosensitive drum 31. A transport paddle 362 that is provided near the opening of the cleaning case 360 and transports the residual toner scraped off by the cleaning blade 361 to the heel side of the cleaning case 360.
[0019]
On the other hand, the developing device 34 adopts, for example, a two-component developing method, and as shown in FIGS. 3 and 4, the downstream side of the latent image writing position P of the photosensitive drum 31 (the lower side in this example). 2) has a developing housing 51 opened to the photosensitive drum 31 side, and a developing roll 52 is disposed facing the opening of the developing housing 51. On the back side of the developing roll 52, developing is performed. A pair of agitating / conveying augers 53 and 54 to which the agent is agitated and conveyed are provided, and the developer agitated and conveyed by the agitating and conveying augers 53 and 54 is transferred to the developing roll 52 and developed by a trimming member (not shown). The developer layer thickness on the roll 52 is regulated, and the developer is supplied to the developing position on the photosensitive drum 31.
[0020]
Further, the developing device 34 includes a toner cartridge 42 on the back side of the developing housing 51.
As shown in FIGS. 3 and 4, the toner cartridge 42 is disposed so as to extend in the vertical direction across the latent image writing position P of the photosensitive drum 31. While a scanning passage 62 through which scanning light from the exposure device 33 passes is opened at a site corresponding to the position P, toner is provided on the upstream side (upper side in this example) of the latent image writing position P of the cartridge case 61. A replenishment box 63 is disposed, and a waste developer collection box 64 is disposed on the downstream side (lower side in this example) of the latent image writing position P.
[0021]
In the present embodiment, the toner replenishment box 63 is a cylindrical box extending along the axial direction of the developing roll 52, and a toner agitator 631 is disposed therein so that the toner does not harden in one place. Stir and mix.
A toner supply duct 65 is connected in communication between the toner supply box 63 and the development housing 51, and the toner supply duct 65 is positioned away from the scanning passage 62 so as not to block the scanning passage 62. Is provided.
The toner supply duct 65 has a toner receiving portion 651 corresponding to a long hole-shaped supply port 632 opened in a part of the toner supply box 63, and from the outer end in the longitudinal direction of the toner receiving portion 651. A connecting pipe 652 communicates with a replenishing port 511 (disposed below the replenishing port 632 of the toner replenishing box 63), and the received toner in the toner receiving part 651 is connected to the connecting pipe 652 by a predetermined amount. A dispense auger 653 to be supplied to the side is arranged.
[0022]
In the present embodiment, the waste developer recovery box 64 is a substantially deformed fan-shaped box that extends along the axial direction of the developing roll 52, and has a recovery port 641 at the upper part of one side thereof. A leveling agitator 642 for leveling the collected waste developer is disposed inside.
On the other hand, a discharge port 512 for discharging the waste developer in the development housing 51 (the normal discharge port 512 is disposed below the collection port 641) is opened at one end in the longitudinal direction of the development housing 51. The deteriorated developer in the housing 51 is periodically discharged from the discharge port 512.
One or a plurality of the discharge ports 512 may be provided so as to be normally opened at a predetermined height position, or a shutter or the like that opens and closes at an appropriate timing may be added.
A waste developer transport mechanism 66 is provided between the recovery port 641 of the waste developer recovery box 64 and the discharge port 512 of the development housing 51.
[0023]
The waste developer transport mechanism 66 is disposed on the side of the development housing 51 and the toner cartridge 42 as shown in FIGS. 4 to 6, for example. The waste developer collection box 64 has a recovery port 641 and a developer. A discharge duct 512 of the housing 51 is hermetically connected by a connection duct 661, a ring-shaped space portion 662 is formed in a part of the connection duct 661, and a recovery fin 663 is disposed in the ring-shaped space portion 662. Is.
Here, as the recovery fins 663, a mode in which a plurality of fin members 665 are provided at predetermined intervals around the rotor 664 is used, and among the connection ducts 661 that define the ring-shaped space portion 662, the recovery fins 663. The recovery port 641 is disposed at a position facing the fin movement locus, and a communication port 666 is opened at a portion corresponding to the recovery port 641. Note that it is possible to reduce the cost if the recovery fins 663 are manufactured by resin molding or the like.
[0024]
Further, in the present embodiment, the process cartridge 40 includes a cartridge holder 401 for holding each photosensitive member cartridge 41, the toner cartridge 42, and other devices as shown in FIG. Is provided with a movable holder 402 to which the toner cartridge 42 is pressed in a swingable manner, and the engagement state between the movable holder 402 and the engagement piece 611 on the toner cartridge 42 side is released, whereby the toner cartridge 42 is removed from the cartridge holder 401. Is made to leave. In FIG. 4, the engagement piece 611 of the toner cartridge 42 is not shown.
[0025]
The process cartridge 40 is provided with a drive transmission system 70.
For example, as shown in FIGS. 7 and 8, the drive transmission system 70 has a drive motor 71 fixed to the apparatus body 20 side, and a drive coupling gear 73 that meshes with a drive shaft gear 72 of the drive motor 71. A coupling 74 is provided, and the drive coupling gear 73 is supported so as to be movable in the axial direction with respect to the apparatus body 20, and the drive coupling gear 73 is separated from the process cartridge 40 by a biasing spring 75. Further, the drive shaft gear 72 and the drive coupling gear 73 are both helical gears, and a torque limiter 76 is attached to the drive coupling gear 73 shaft.
On the other hand, the cartridge holder 401 of the process cartridge 40 is provided with a CRU side coupling 77, and the CRU side coupling 77 is releasably connected to the drive side coupling 74.
[0026]
In the present embodiment, the drive transmission system 70 operates as follows.
That is, when the drive motor 71 is transmitted in a predetermined direction, a thrust force in the direction of arrow A in the figure is generated at the meshing portion of the drive shaft gear 72 and the drive coupling gear 73 due to the rotational direction and the torque limiter 76 load. . Then, the driving side coupling 74 is coupled to the CRU side coupling 77 against the biasing force of the biasing spring 75 by this thrust force.
On the other hand, when the drive motor 71 is stopped, the thrust force disappears in the meshing portion of the drive shaft gear 72 and the drive coupling gear 73, so that the drive side coupling 74 is moved backward by the biasing force of the biasing spring 75, The connection state between the drive side coupling 74 and the CRU side coupling 77 is released.
When releasing the coupled state of the coupling, the drive motor 71 is rotated in the reverse direction to that at the time of coupling, and thereby the meshing portion of the drive shaft gear 72 and the drive coupling gear 73 is in the direction opposite to that at the time of coupling. A thrust force may be generated to release the connection state between the two.
If such a connection release mechanism is used, a separate separate part is not required for releasing the coupling of the coupling, and the structure of the connection release mechanism can be simplified correspondingly.
[0027]
Next, the operation of the image forming apparatus according to the present embodiment will be described.
As shown in FIG. 2, in the process cartridge 40, the photosensitive drum 31 is charged by the charging device 32, and a latent image is formed on the photosensitive drum 31 by the exposure device 33, and then visible by the developing device 34. An image (toner image) is formed.
On the other hand, the sheet is fed from the sheet supply device 22 to the sheet conveyance path 23 at a predetermined timing, positioned by the registration roll 24 and then conveyed to the transfer site.
Then, the toner image on the photosensitive drum 31 is transferred to a sheet by the transfer device 35, and after the unfixed toner image on the sheet is fixed by the fixing device 25, the fixed sheet is discharged to the discharge tray 27. . The residual toner on the photosensitive drum 31 is cleaned by the cleaning device 36.
[0028]
In such an image forming process, the scanning light from the exposure device 33 reaches the latent image writing position P of the photosensitive drum 31 through the scanning path 62 of the process cartridge 40. There is no concern of impairing exposure scanning.
In the developing device 34, the amount of toner consumption increases as the image forming process proceeds. However, according to the algorithm of the toner supply control device (not shown), new toner in the toner supply box 63 enters the development housing 51 through the toner supply duct 65. It is replenished sequentially.
The new toner replenished in the developing housing 51 is agitated and mixed with the developer in the developing housing 51 by the agitating / conveying augers 53 and 54, and supplied to the developing roll 52 side with a predetermined charging characteristic. The developer held on the developing roll 52 is supplied to the developing area with the photosensitive drum 31.
[0029]
Further, in the developing device 34, a part of the developer in the developing housing 51 is circulated and moved in the developing housing 51 by the agitating / conveying augers 53 and 54 without being used for development.
Since such a developer is deteriorated and it becomes difficult to maintain charging characteristics and the like, in this embodiment, waste developer (mainly deteriorated developer) is periodically discharged from the discharge port 512 of the development housing 51. Alternatively, it is discharged at a predetermined timing.
As shown in FIGS. 4 and 5, the waste developer is transported to the recovery fins 663 in the waste developer transport mechanism 66 and enters the waste developer recovery box 64 through the recovery port 641 of the waste developer recovery box 64. After falling and recovered, the material is appropriately leveled by a leveling agitator 642.
[0030]
A layout of the process cartridge 40 in the apparatus main body 20 is shown in FIG.
As a comparative form, a toner cartridge 42 ′ (in this example, only a toner replenishing box 63 ′ is provided) is incorporated downstream of the latent image writing position P of the photosensitive drum 31 (downward in this example). A process cartridge 40 'is shown.
Here, when comparing the process cartridge 40 according to the present embodiment with the process cartridge 40 ′ according to the comparative embodiment, the bottom position of the process cartridge 40 according to the present embodiment is in the comparative embodiment. Compared with the sheet feeding device 22 and the like disposed in the lower part of the apparatus main body 20, the restrictions on the layout are eliminated.
[0031]
In the present embodiment, since the toner supply box 63 is disposed on the upstream side (the upper side in this example) of the latent image writing position P of the photosensitive drum 31, the apparatus main body is compared with the comparative embodiment. The occupied space in the space above the scanning light line k in 20 increases. However, originally, in the comparative form, the lower space of the discharge tray 27 in the apparatus main body 20 was a dead space D. Therefore, the dead space D is effectively used, and the space occupied by the toner supply box 63 is Therefore, when using the process cartridge 40 according to the present embodiment, it is not necessary to significantly change the upper specification of the apparatus main body 20.
Further, even when the toner supply amount in the toner supply box 63 is increased, for example, if the upper space in the apparatus main body 20 is used effectively, the upper specification (discharge tray) of the apparatus main body 20 is used. 27 around) is almost unchanged.
Therefore, the apparatus main body 20 can be shared when constructing image forming apparatuses of various specifications.
In addition, even if the upper specification of the apparatus main body 20 is unavoidably changed, a slight specification change such as slightly raising the position of the discharge tray 27 is sufficient. For this reason, when the lower space of the apparatus main body 20 is compressed as in the comparative embodiment, a large specification change such as changing the layout on the sheet supply apparatus 22 side is required. So, no major specification changes are required.
[0032]
Next, the attaching / detaching operation of the process cartridge 40 according to the present embodiment will be described.
In the present embodiment, a cartridge receiving portion 80 in which the process cartridge 40 is detachable is formed in the apparatus main body 20, and this cartridge receiving portion 80 is a guided portion of the cartridge holder 401 of the process cartridge 40. A guide portion 81 such as a guide groove that is movably engaged is provided.
In this embodiment, a part of the bottom wall of the discharge tray 27 is formed as an opening / closing cover 82, and the opening when the opening / closing cover 82 is released is a work opening 83 for attaching / detaching the process cartridge 40. It has come to be used as.
[0033]
First, when removing the process cartridge 40 from the apparatus main body 20, for example, as shown in FIG. 10, after opening the opening / closing cover 82, the process cartridge 40 is pulled out from the cartridge receiving portion 80 of the apparatus main body 20 through the work opening 83. What should I do?
In this state, for example, when the photoconductor cartridge 41 is replaced, the photoconductor cartridge 41 may be removed from the process cartridge 40 as shown in FIG.
As shown in FIG. 3, the cartridge case 411 of the photoconductor cartridge 41 has engaging portions 412 that can be freely engaged with and disengaged from the plurality of engaged portions 403 on the cartridge holder 401 side. On the other hand, it is detachably positioned and mounted.
[0034]
In the present embodiment, the toner cartridge 42 can be removed from the process cartridge 40.
In this case, as shown in FIG. 12, the movable holder 402 of the cartridge holder 401 is moved down to release the restraint state of the toner cartridge 42 by the movable holder 402, and then the toner cartridge 42 is substantially removed from the cartridge holder 401. What is necessary is just to make it pull out upwards.
Here, in the present embodiment, the toner cartridge 42 may be replaced after the process cartridge 40 is taken out from the apparatus main body 20, but the process cartridge 40 is removed from the apparatus main body 20 as shown in FIG. In addition, it is possible to release the restraint state of the toner cartridge 42 by the movable holder 402, and then draw the toner cartridge 42 from the process cartridge 40 substantially upward. It is kept good.
[0035]
In particular, in the present embodiment, since the photosensitive cartridge 41 and the toner cartridge 42 that are detachable from the process cartridge 40 are provided, the lifetimes of the respective cartridges are different, but they are effectively used up to the respective longest expiration dates. This is preferable.
In this embodiment, since the toner supply box 63 and the waste developer recovery box 64 are integrally provided in the toner cartridge 42, the toner supply box 63 and the waste development can be replaced by replacing the toner cartridge 42. It is possible to replace the agent recovery box 64 at the same time.
Therefore, according to the present embodiment, it is not necessary to use another cartridge for collecting the waste developer, and the operability can be improved and the cost can be reduced. Furthermore, since it is only necessary to define the replacement timing of the toner cartridge 42 by detecting empty of the replenished toner, it is not necessary to detect whether the waste developer collection box 64 is full.
[0036]
Further, in the present embodiment, the toner cartridge 42 includes a toner replenishment box 63 and a waste developer collection box 64. For example, as shown in FIG. 14, waste toner from the cleaning device 36 is accommodated. Different waste developer collection boxes 68 may be added as necessary.
[0037]
【The invention's effect】
  As described above, according to the present invention, the layout of the developer replenishment box and the waste developer collection box is devised so that the latent image writing position on the image carrier is sandwiched between them.DirectionThe developer supply box on the side,DirectionOn the sideDevelopment housing andSince the waste developer collection box is provided, the developer replenishment function and the waste developer collection function can be compatible while satisfying the demand for downsizing the apparatus.
  In particular, in the present invention, the latent image writing position is overwritten.DirectionSince the developer supply box is disposed on the side, for example, in an image forming apparatus that conveys a sheet substantially upward in the vertical direction, the upper space of the latent image writing position is not set as a dead space. It can be effectively used as a developer replenishment space, and can easily cope with changes in specifications such as the developer replenishment amount with little influence on other elements.
  Furthermore, since the developer replenishment box and the waste developer collection box are integrated into one unit, it is not necessary to use a separate cartridge for collecting the waste developer, and the operability can be improved and the cost can be reduced. Furthermore, since it is only necessary to define the replacement timing of the unit including both boxes by detecting empty of the replenishment developer, it is not necessary to detect the fullness of the waste developer collection box.
[0038]
Further, according to the process cartridge and the developing device used in the image forming apparatus according to the present invention, it is possible to easily cope with a change in specifications such as downsizing of the image forming apparatus and a developer replenishment amount, and a dead space is generated in the apparatus. Therefore, it is possible to easily realize an image forming apparatus that can achieve both the developer replenishing function and the waste developer collecting function.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an outline of an image forming apparatus, a process cartridge, and a developing device according to the present invention.
FIG. 2 is an explanatory diagram illustrating an overall configuration of the image forming apparatus according to the first embodiment.
FIG. 3 is an explanatory diagram showing details of a process cartridge used in the present embodiment.
FIG. 4 is an exploded perspective view of a main part of a process cartridge including a waste developer conveyance mechanism.
FIG. 5 is an explanatory diagram showing details of a process cartridge including a waste developer conveyance mechanism.
6A is an explanatory view showing a waste developer transport mechanism, and FIG. 6B is a cross-sectional explanatory view taken along line BB in FIG. 6A.
FIG. 7 is an explanatory diagram showing a drive transmission system of a process cartridge.
8 is a view as seen from an arrow VIII in FIG.
FIG. 9 is an explanatory diagram showing a layout difference between a process cartridge according to an embodiment and a process cartridge according to a comparative embodiment;
FIG. 10 is an explanatory diagram showing an example of a process cartridge attaching / detaching operation according to the present embodiment.
FIG. 11 is an explanatory diagram showing a relationship between a process cartridge and a photosensitive cartridge.
FIG. 12 is an explanatory diagram showing a relationship between a process cartridge, a developer supply box, and a waste developer collection box.
FIG. 13 is an explanatory diagram showing an example of replacement work of a developer supply box and a waste developer recovery box.
FIG. 14 is an explanatory view showing a modified form of a development supply box and a waste developer collection box.
[Explanation of symbols]
  DESCRIPTION OF SYMBOLS 1 ... Image carrier, 2 ... Latent image formation means, 3 ... Developing apparatus, 4 ... Developing housing, 5 ... Developer supply box, 6 ... Waste developer collection box, 7 ... Apparatus main body, 7a ... Opening / closing cover, 7b ... Ejection tray, 8 ... process cartridge, 9 (9a, 9b) ... process unit, 10 ... transferapparatus, P ... latent image writing position, S ... sheet

Claims (9)

A latent image forming means for forming a latent image on the image carrier, a developing device for visualizing the latent image formed on the image carrier with a developer , and a visible image formed on the image carrier An image forming engine provided in the apparatus main body, including a transfer device for transferring an image to a sheet;
A discharge tray provided at an upper part of the apparatus main body and having an inclined portion that is lower on the discharge outlet side from which the sheet of the apparatus main body is discharged and becomes higher as the distance from the discharge outlet increases;
A sheet supply device provided below the image forming engine in the apparatus main body,
In the image forming apparatus of the aspect in which the sheet supplied from the sheet supply apparatus is conveyed from the lower side to the upper side on one side of the apparatus main body and discharged to the discharge tray through the transfer portion of the transfer apparatus.
The developing device communicates with each other a developer replenishment box capable of replenishing the developer and a waste developer collection box capable of recovering the waste developer in the development housing in a development housing in which the developer is accommodated.
Lower the a lower inclined portion of the discharge tray on the upper sides of the latent image writing position on the image bearing member is disposed to the developer-supply box, and, across the latent image writing position On the side, the developing housing and the waste developer recovery box are disposed adjacent to each other in the horizontal direction ,
Further, the developer supply box and the waste developer recovery box are configured as one unit with the scanning light path for latent image writing interposed therebetween, and the developer supply box and the waste developer recovery box are provided with respect to the development housing. An image forming apparatus characterized by being separable integrally . The image forming apparatus according to claim 1.
A process cartridge that is detachably attached to the apparatus main body and includes an image carrier and at least one process unit;
An image forming apparatus, wherein the process cartridge includes the developer supply box and a waste developer recovery box. The image forming apparatus according to claim 2 .
An image forming apparatus, wherein the developer supply box and the waste developer collection box are detachable from the process cartridge. The image forming apparatus according to claim 2 or 3 ,
An image forming apparatus, wherein an image carrier cartridge including at least an image carrier is detachable from a process cartridge. The image forming apparatus according to claim 2 ,
An image forming apparatus, wherein the process cartridge is detachable from above by opening an opening / closing cover at an upper part of the apparatus main body. The image forming apparatus according to claim 1 ,
The replenishment port of the developer replenishment box is offset above the developer accommodating portion of the development housing, and the new developer from the developer replenishment box is positioned away from the latent image writing position on the image carrier. An image forming apparatus configured to be supplied to a developing housing through a supply path. The image forming apparatus according to claim 1 ,
The collection port of the waste developer collection box is offset above the waste developer discharge port of the development housing, and the waste developer discharged from the development housing is disposed above the rotating conveyance body. An image forming apparatus, wherein the image forming apparatus is transported to a recovery port of an agent recovery box. A process cartridge used in the image forming apparatus according to claim 2 . A developing device for use in an image forming apparatus according to any one of claims 1 to 7.

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