JP2018010259A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus that can suppress an image carrier to which a residual toner is concentratedly moved from being replaced earlier than the expiration of its life, while suppressing an increase in size and a reduction in usability of the apparatus.SOLUTION: An image forming apparatus 100 removes a toner remaining on a plurality of image carriers 1 after primary transfer with corresponding cleaning members 61, and charges a toner remaining on an intermediate transfer body 7 after secondary transfer with charging means 15, moves the charged toner to the image carriers 1, and removes the charged toner with the corresponding cleaning members 61. The image forming apparatus comprises a common recovery container 30 that recovers a toner removed from at least two image carriers 1 of the plurality of image carriers 1 by the corresponding cleaning members 61, and the recovery container 30 is removably attached to an apparatus body 110 of the image forming apparatus 100 independent of the plurality of image carriers 1 and the plurality of cleaning members 61.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, or a facsimile apparatus using an electrophotographic system or an electrostatic recording system.

  2. Description of the Related Art Conventionally, for example, in an image forming apparatus using an electrophotographic method, a toner image formed on a photoconductor as an image carrier is primarily transferred to an intermediate transfer member and then secondarily transferred to a transfer material such as paper. There is an intermediate transfer system. The intermediate transfer system has high media flexibility that can form an image on a wide variety of transfer materials. In particular, the color image forming apparatus has an in-line method in which a plurality of image forming portions each having a photoconductor are provided, and a toner image formed on each photoconductor is sequentially primary transferred so as to be superimposed on an intermediate transfer body. Widely used.

  In the intermediate transfer type image forming apparatus, it is necessary to clean the residual toner remaining on the intermediate transfer body without being transferred to the transfer material during the secondary transfer. As a cleaning method for the intermediate transfer member, there is the following electrostatic recovery method for electrostatically cleaning residual toner on the intermediate transfer member (Patent Document 1).

  The residual toner on the intermediate transfer member is charged to a polarity opposite to the charging polarity (normal charging polarity) of the toner at the time of development by the charging unit, and the residual toner is moved to the photosensitive member at the primary transfer portion. Since the residual toner can be moved from the intermediate transfer member to the photosensitive member at the same time as the primary transfer of the toner image from the photosensitive member to the intermediate transfer member, this cleaning method is also called a simultaneous transfer recovery method. Then, the residual toner moved to the photoconductor is removed from the photoconductor and collected by a photoconductor cleaning means for cleaning the photoconductor. As the photosensitive member cleaning means, a cleaning device including a cleaning member that removes residual toner from the photosensitive member and a cleaning container that supports the cleaning member and stores the residual toner is widely used.

JP 2009-205012 A

  In the electrostatic recovery method, the residual toner on the intermediate transfer member is intensively moved to the photosensitive member located closest to the downstream side of the charging unit in the moving direction of the intermediate transfer member. In other words, in addition to the residual toner remaining on the photoconductor during the primary transfer, the residual toner moved from the intermediate transfer body is added to the cleaning container of the cleaning device provided corresponding to the photoconductor. Become.

  Here, in order to facilitate maintenance such as replacement of the photosensitive member and disposal of the collected residual toner, the photosensitive member, the cleaning member, and the cleaning container can be integrally attached to and detached from the apparatus main body of the image forming apparatus. May be built into the cartridge. In this case, the cleaning container is replaced when the photosensitive member reaches the end of its life. However, if the residual toner on the intermediate transfer member is intensively moved to a specific photosensitive member as described above, the cleaning container becomes full of toner, and the cartridge must be replaced before the photosensitive member reaches the end of its life. There is a possibility that it will not be.

  In order to make it possible to use the cartridge until the photoconductor reaches the end of its life, it is conceivable to increase the capacity of the cleaning container. However, increasing the capacity of the cleaning container increases the size of the cartridge. Since many process devices are arranged around the photosensitive member, if the capacity of the cleaning container is increased to increase the size of the cartridge, the size of the image forming apparatus tends to increase.

  In order to use the cartridge until the photoconductor reaches the end of its life, it is conceivable that the cleaning container is separated from the photoconductor. However, for example, when the image forming apparatus can perform image formation in a plurality of image forming modes such as the full color mode and the black single color mode, the photosensitive member to which the residual toner is moved intensively from the intermediate transfer member differs depending on the image forming mode. There is. In such a case, if the cleaning container provided corresponding to each photoconductor is separated from the other elements of each cartridge, the configuration of the image forming apparatus becomes complicated and usability is reduced.

  Therefore, an object of the present invention is to suppress the replacement of the image carrier on which the residual toner is moved intensively earlier than the lifetime while suppressing the enlargement of the apparatus and the decrease in usability. An image forming apparatus is provided.

  The above object is achieved by the image forming apparatus according to the present invention. In summary, the present invention provides a plurality of image carriers that carry toner images, an intermediate transfer member that conveys a toner image that has been primarily transferred from the plurality of image carriers, to a transfer material, and a secondary transfer member. A cleaning member that is provided corresponding to each of the plurality of image carriers and removes the toner on the corresponding image carrier, and a charging unit that charges the toner on the intermediate transfer member, In the image forming apparatus in which the toner remaining on the intermediate transfer member after the secondary transfer is charged by the charging unit, moved to the image carrier and removed by the corresponding cleaning member, the plurality of image carriers A common collection container for collecting the toner removed by the corresponding cleaning member from at least two of the image carriers, wherein the collection container includes the plurality of image carriers and An image forming apparatus, wherein the serial to the plurality of cleaning members is removable independently from the apparatus body of the image forming apparatus.

  According to the present invention, it is possible to suppress the replacement of the image carrier on which the residual toner is moved intensively earlier than the lifetime, while suppressing the enlargement of the apparatus and the decrease in usability.

1 is a schematic longitudinal sectional view of an image forming apparatus according to an embodiment. It is a schematic diagram for demonstrating a contact-separation mechanism. It is a schematic sectional drawing of a cartridge. FIG. 6 is a schematic diagram of a toner conveying member. FIG. 5 is a schematic cross-sectional view of a mechanism for transporting toner to a collected toner box. FIG. 5 is a schematic perspective view of a mechanism for transporting toner to a collected toner box. It is a schematic diagram for explaining unit exchange of the image forming apparatus. It is a schematic sectional drawing of the image forming apparatus of another Example. It is a schematic sectional drawing of the cartridge in other Example. It is a schematic sectional drawing of the image forming apparatus of a comparative example.

  The image forming apparatus according to the present invention will be described below in more detail with reference to the drawings.

[Example 1]
1. FIG. 1 is a schematic sectional view of an image forming apparatus 100 according to the present embodiment. The image forming apparatus 100 according to the present exemplary embodiment is an inline type (tandem type) laser beam printer that employs an intermediate transfer method and can form a full-color image using an electrophotographic method.

  The image forming apparatus 100 includes first, second, and second toner images that form yellow (Y), magenta (M), cyan (C), and black (K) toner images, respectively, as a plurality of image forming units (stations). It has third and fourth image forming units PY, PM, PC, PK. For the same or corresponding elements in each of the image forming units PY, PM, PC, and PK, Y, M, C, and K at the end of the symbol indicating that it is an element for any color are omitted and collectively May be explained. In the present embodiment, the image forming unit P includes a photoconductor 1, a charging roller 2, an exposure device 3, a developing device 4, a primary transfer roller 5, and a cleaning device 6 which will be described later.

  A drum-type photosensitive member (photosensitive drum) 1 as an image carrier that carries a toner image is driven to rotate in the direction of an arrow R1 (clockwise) in the drawing. The surface of the rotating photosensitive member 1 is uniformly charged to a predetermined potential having a predetermined polarity (negative polarity in this embodiment) by a charging roller 2 as a photosensitive member charging unit. During the charging process, a negative charging voltage (charging bias) is applied to the charging roller 2. The surface of the charged photosensitive member 1 is scanned and exposed with a laser beam L based on image information by an exposure device (laser scanner) 3 as an exposure unit, and an electrostatic latent image (electrostatic image) is formed on the photosensitive member 1. Is formed. In the present embodiment, the exposure apparatus 3 is configured as one unit (laser optical unit) that exposes each photoreceptor 1 of each image forming unit P.

  The electrostatic latent image formed on the photosensitive member 1 is developed (visualized) by supplying toner as a developer by a developing device 4 as developing means, and a toner image is formed on the photosensitive member 1. The developing device 4 includes a developing roller 41 as a developer carrying member that conveys toner to a portion (developing portion) facing the photoreceptor 1, and a developing container 42 that contains the toner. Each of the developing containers 42Y, 42M, 42C, and 42K contains toner of each color of yellow, magenta, cyan, and black. During the development process, a development voltage (development bias) having a smaller absolute value than the charging potential of the photoreceptor 1 and a negative polarity is applied to the development roller 41. In this embodiment, the same polarity as the charging polarity of the photosensitive member 1 (negative polarity in this embodiment) is applied to the exposed portion on the photosensitive member 1 where the absolute value of the potential is reduced by exposure after being uniformly charged. ) Is charged with charged toner. That is, in this embodiment, the charging polarity (normal charging polarity) of the toner during development is negative.

  An intermediate transfer belt 7 formed of an endless belt is disposed facing each of the photoreceptors 1Y, 1M, 1C, and 1K. The intermediate transfer belt 7 is an example of an intermediate transfer member that conveys a toner image that has been primarily transferred from a plurality of image carriers to a transfer material for secondary transfer. The intermediate transfer belt 7 is stretched by a driving roller 71 that also serves as a secondary transfer counter roller, a tension roller 72, and an idler roller 73 as a plurality of stretching rollers. The intermediate transfer belt 7 is rotationally driven by a driving roller 71 in the direction of arrow R2 (counterclockwise) in the drawing. On the inner peripheral surface side of the intermediate transfer belt 7, a primary transfer roller 5, which is a roller-type primary transfer member serving as a primary transfer unit, is disposed corresponding to each photoreceptor 1. The primary transfer roller 5 is pressed toward the photoconductor 1 via the intermediate transfer belt 7 to form a primary transfer portion (primary transfer nip) N1 where the photoconductor 1 and the intermediate transfer belt 7 are in contact with each other. The toner image formed on the photoreceptor 1 as described above is electrostatically transferred (primary transfer) onto the rotating intermediate transfer belt 7 in the primary transfer portion N1. During the primary transfer process, the primary transfer roller 5 receives a primary transfer voltage, which is a DC voltage having a polarity opposite to the normal charging polarity of the toner (positive polarity in this embodiment) from the primary transfer power supply (high voltage power supply circuit) E1. Applied. For example, when forming a full-color image, yellow, magenta, cyan, and black toner images formed on the respective photoreceptors 1 are sequentially transferred so as to be superimposed on the intermediate transfer belt 7.

  On the outer peripheral surface side of the intermediate transfer belt 7, a secondary transfer roller that is a roller-type secondary transfer member as a secondary transfer unit is disposed at a position facing the driving roller 71. The secondary transfer roller 8 is pressed toward the drive roller 71 via the intermediate transfer belt 7, and passes through a secondary transfer portion (secondary transfer nip) N <b> 2 where the intermediate transfer belt 7 and the secondary transfer roller 8 are in contact with each other. Form. As described above, the toner image formed on the intermediate transfer belt 7 is transferred to a transfer material (recording material) such as paper conveyed between the intermediate transfer belt 7 and the secondary transfer roller 8 in the secondary transfer portion N2. , Electrostatically transferred (secondary transfer) onto the recording medium or sheet S. During the secondary transfer process, the secondary transfer roller 8 receives a secondary voltage from the secondary transfer power supply (high voltage power supply circuit) E2, which is a DC voltage having a polarity opposite to the normal charging polarity of the toner (positive in this embodiment). A next transfer voltage is applied. The transfer material S is loaded on the transfer material cassette 11, is fed by a pickup roller 12, and is conveyed to the registration roller 13. The transfer material S is supplied to the secondary transfer portion N2 after the skew is corrected by the registration roller 13 and then in time with the toner image on the intermediate transfer belt 7.

  The transfer material S onto which the toner image has been transferred is conveyed to a fixing device 9 as a fixing unit, where the toner image is fixed (melted and fixed) on the surface by being heated and pressed. Thereafter, the transfer material S is discharged (output) to the outside of the apparatus main body 110 of the image forming apparatus 100.

  On the other hand, residual toner (primary transfer residual toner) remaining on the photoreceptor 1 during the primary transfer process is removed from the photoreceptor 1 and collected by a cleaning device 6 as a cleaning unit. The cleaning device 6 includes a cleaning blade 61 disposed in contact with the photoreceptor 1, and a cleaning container 62 that supports the cleaning blade 61 and stores residual toner. The cleaning blade 61 is an example of a cleaning member that removes toner on the image carrier. The cleaning blade 61 is a plate-like (blade-like) member made of rubber (such as urethane rubber) as an elastic material. The cleaning blade 61 is disposed so that its longitudinal direction is substantially parallel to the longitudinal direction (rotation axis direction) of the photosensitive member 1, and one end portion (free end portion) in the short side direction is located upstream of the rotational direction of the photosensitive member 1. It is in contact with the surface of the photoreceptor 1 in the counter direction that faces. The cleaning device 6 scrapes residual toner from the surface of the rotating photoreceptor 1 with a cleaning blade 61 and stores it in a cleaning container 62. The cleaning device 6 will be described in more detail later.

  Further, the residual toner (secondary transfer residual toner) remaining on the intermediate transfer belt 7 in the secondary transfer process is recovered by an electrostatic recovery method. The cleaning of the intermediate transfer belt 7 will be described in detail later.

  The operation of each unit of the image forming apparatus 100 is controlled in an integrated manner by a control unit 120 as a control unit provided in the apparatus main body 110.

  Here, in each image forming unit P, the photosensitive member 1 and the charging roller 2, the developing device 4, and the cleaning device 6 as process means acting on the photosensitive member 1 are integrally detachable from the apparatus main body 110 (see FIG. Process cartridge) 10 (FIG. 3) is formed. In this embodiment, in the apparatus main body 110, the cartridges 10Y, 10M, 10C, and 10K are arranged side by side in the direction intersecting the gravity direction along the moving direction of the intermediate transfer belt 7.

In this embodiment, the photoreceptor 1 is configured by applying an organic photoconductor layer (OPC photoreceptor) on the outer peripheral surface of an aluminum cylinder having a diameter of 30 mm. In this embodiment, the intermediate transfer belt 7 is composed of an endless film member having a thickness of about 50 to 150 μm and having a volume resistivity of 10 ⁷ to 10 ¹⁴ Ωcm. The volume resistivity is a value obtained by applying 50 to 100 V at a temperature of 25 ° C. and a relative humidity of 50% with a high resistance meter R2340 manufactured by ADVANTEST, using a measurement probe in accordance with JIS method K6911. It is.

2. Image Forming Mode In this embodiment, the image forming apparatus 100 can perform image forming in two image forming modes, a full color mode (first mode) and a mono mode mode (second mode). In the full color mode, a toner image can be formed by the first to fourth image forming units PY, PM, PC, and PK to form a full color image. In the mono mode, it is possible to form a black monochrome image by forming a toner image only with the fourth image forming unit PK among the first to fourth image forming units PY, PM, PC, and PK.

  In the full color mode, as shown in FIG. 2A, the primary transfer roller 5 is pressed toward the photoconductor 1 in all the image forming units PY, PM, PC, PK, and the photoconductor 1 and the intermediate transfer belt. 7 is contacted.

  On the other hand, in the mono mode, as shown in FIG. 2B, the contact / separation mechanism 20 performs primary transfer from the photoreceptor 1 in the first to third image forming portions PY, PM, and PC that are not used for image formation. The roller 5 is moved away and the intermediate transfer belt 7 is separated from the photoreceptor 1. In the mono mode, in the first to third image forming units PY, PM, and PC, driving of the cartridge 10 such as the photosensitive member 1, the charging roller 2, and the developing device 4 is stopped. Thereby, unnecessary operations can be suppressed and the life of the cartridge 10 can be extended. In this embodiment, after the printing in the mono mode is completed, the intermediate transfer belt 7 is brought into contact with the photosensitive member 1 in all the image forming units PY, PM, and PC to prepare for the next printing.

3. Cleaning of the intermediate transfer belt The residual toner remaining on the intermediate transfer belt 7 at the time of secondary transfer is set to a normal charging polarity of the toner by a cleaning brush 15 as a charging member (toner charging unit), which is a brush-like charging member. Is charged to a reverse polarity (positive polarity in this embodiment).

As the cleaning brush 15, a brush configured so that conductive nylon fibers having an electric resistance of 10 ⁶ to 10 ⁹ Ω are substantially dense is used. The cleaning brush 15 is disposed so as to contact the intermediate transfer belt 7 downstream of the secondary transfer portion N2 and upstream of the primary transfer portion N1 (upstreammost primary transfer portion N1Y) in the rotation direction of the intermediate transfer belt 7. In the present embodiment, the cleaning brush 15 is fixedly disposed at a position facing the tension roller 72 via the intermediate transfer belt 7. The length of the cleaning brush 15 in the longitudinal direction (direction substantially orthogonal to the moving direction of the intermediate transfer belt 7) is equal to or longer than the length of the image forming area (area where toner images can be formed) on the intermediate transfer belt 7 in the same direction. It is. In this embodiment, the width of the cleaning brush 15 in the short direction (the moving direction of the intermediate transfer belt 7) is 4 mm. The cleaning brush 15 is arranged to be pressed toward the tension roller 72 via the intermediate transfer belt 7 so that the position of the tip of the brush fiber becomes an intrusion amount of 1.0 mm with respect to the surface of the intermediate transfer belt 7. ing. A contact portion between the cleaning brush 15 and the intermediate transfer belt 7 is a charging portion CL that charges the residual toner on the intermediate transfer belt 7 with the cleaning brush 15.

  A voltage of +1.0 to +2.0 kV can be applied to the cleaning brush 15 from the cleaning power supply (high voltage power supply circuit) E3 as a cleaning voltage that is a DC voltage having a polarity opposite to the normal charging polarity of the toner. ing. The purpose of the cleaning brush 15 is to charge the residual toner on the intermediate transfer belt 7 to an appropriate charge amount for electrostatically moving (reverse transfer) to the photoreceptor 1 at the primary transfer portion N1. The cleaning brush 15 also serves to disperse residual toner on the intermediate transfer belt 7. In this embodiment, the cleaning voltage applied to the cleaning brush 15 is set to +1.5 kV in order to give an appropriate charge to the remaining toner on the intermediate transfer belt 7.

  In the full color mode, the residual toner on the intermediate transfer belt 7 charged by the cleaning brush 15 is moved to the yellow photoreceptor 1Y. The remaining toner is removed from the yellow photoreceptor 1Y by the yellow cleaning device 6 and collected. Therefore, in the full color mode, the amount of residual toner collected by the yellow cleaning device 6Y is not limited to the primary transfer residual toner, but the secondary transfer residual toner on the intermediate transfer belt 7 is added. More than devices 6M, 6C, 6K.

  On the other hand, in the mono mode, the residual toner on the intermediate transfer belt 7 charged by the cleaning brush 15 is moved to the black photoreceptor 1K. The residual toner is removed from the black photoreceptor 1K by the black cleaning device 6K and collected. Therefore, in the mono mode, the amount of residual toner collected by the black cleaning device 6K is added to the secondary transfer residual toner on the intermediate transfer belt 7 in addition to the primary transfer residual toner. More than devices 6Y, 6M, 6C.

  The ratio at which the full color mode and the mono mode are executed differs depending on how the image forming apparatus 100 is used by the user. However, in the configuration of this embodiment, as described above, the amount of residual toner collected by the cleaning devices 6Y and 6K for yellow and black is the remaining toner collected by the cleaning devices 6M and 6C for other colors. Will be more than the amount.

4). Toner Collection Next, the remaining toner collection method in this embodiment will be described in more detail. In the following description, the first, second, third, and fourth image forming units PY, PM, PC, PK or elements thereof are prefixed with “Y”, “M”, “C”, “ K ”may be used for distinction.

  3A is a schematic cross-sectional view of Y / K cartridges 10Y and 10K in the present embodiment, and FIG. 3B is a schematic cross-sectional view of MC cartridges 10M and 10C in the present embodiment. In this embodiment, the Y / K cartridges 10Y and 10K and the M and C cartridges 10M and 10C have different configurations. In this embodiment, the Y · K cartridges 10Y and 10K and the M · C cartridges 10M and 10C are substantially different except that the color of the toner contained in the developing container 42 and the configuration of the cleaning device 6 are different. Have the same configuration.

  First, the MC cleaning devices 6M and 6C shown in FIG. 3B will be described. In the M / C cleaning devices 6M and 6C, the residual toner removed from the M / C photoconductors 1M and 1C by the M / C cleaning blades 61M and 61C falls free and the M / C cleaning container 62M serves as a recovery container. , 62C is finally collected. The M / C cleaning containers 62M and 62C together with the M / C photoreceptors 1M and 1C and the M / C cleaning blades 61M and 61C form a substantially sealed residual toner storage space. The residual toner collected in the M / C cleaning containers 62M, 62C is discarded by replacing the M / C cartridges 10M, 10C.

  Next, the Y / K cleaning devices 6Y and 6K shown in FIG. In the Y / K cleaning devices 6Y and 6K, the residual toner removed from the Y / K photoconductors 1Y and 1K by the Y and K cleaning blades 61Y and 61K is transferred to the Y and K cleaning containers 62Y and 62K as temporary collection containers. Once accommodated. The residual toner once stored in the Y / K cleaning containers 62Y and 62K is collected in common through the Y / K vertical ducts 51Y and 51K and the horizontal duct 52 (FIG. 1) constituting the transport unit 50. The toner is collected in a collected toner box 30 (FIG. 1) as a container. The Y / K cleaning containers 62Y and 62K as the temporary collection containers can be made smaller than the M / C cleaning containers 62M and 62C as the collection containers. In this embodiment, the Y / K cleaning containers 62Y and 62K have a volume as small as possible within a range in which the remaining toner can be sufficiently temporarily accommodated in relation to the conveyance capability of the container screws 63Y and 63K described later. It is configured as follows.

  Inside the Y / K cleaning containers 62Y and 62K, container screws 63Y and 63K are provided as conveying members. In this embodiment, the Y / K cartridges 10Y and 10K are mounted on the apparatus main body 110, so that drive receiving portions (not shown) for the Y / K photoconductors 1Y and 1K are provided on the apparatus main body 110. And a drum drive motor (not shown). The rotational driving force of the Y · K photoconductor 1 is transmitted to the container screws 63Y and 63K via a drive transmission unit (not shown) provided in the Y · K cartridges 10Y and 10K. Accordingly, the container screws 63Y and 63K are driven to rotate in synchronization with the Y · K photoconductors 1Y and 1K. By the container screws 63Y and 63K, the remaining toner in the Y / K cleaning containers 62Y and 62K is moved along the longitudinal direction of the Y / K cleaning blades 61Y and 61K in the rear side of the apparatus main body 110 in this embodiment (see FIGS. To the back side of the paper).

  FIG. 4 is a schematic view of an example of a screw conveyor that can be used as the container screws 63Y and 63K. The screw conveyor can convey the toner in a direction substantially parallel to the rotation axis by rotating. In this example, a screw conveyor of the type shown in FIG. 4A was used. The conveying member capable of conveying the toner is not limited to the screw conveyor, and for example, a belt method may be used.

  FIG. 5 is a schematic cross-sectional view of the Y / K vertical ducts 51 </ b> Y and 51 </ b> K and the horizontal duct 52 constituting the transport unit 50. The residual toner conveyed by the container screws 63Y and 63K passes through the discharge ports 64Y and 64K, which are openings provided at the bottom of the Y / K cleaning containers 62Y and 62K, and passes through the Y and K vertical ducts 51Y and 51K. It falls freely and moves into the lateral duct 52. Inside the horizontal duct 52, a duct screw 53 as a conveying member is provided. The residual toner that has moved into the horizontal duct 52 is conveyed toward the collected toner box 30 by the duct screw 53. In this embodiment, as the duct screw 53, a screw conveyor of the same type as the container screws 63Y and 63K is used (as described above, but not limited to this). The duct screw 53 is provided with a duct screw drive motor (not shown) as drive means provided in the apparatus main body 110, and the residual toner sent to the horizontal duct 52 along with image formation is sent to the collected toner box 30 without delay. It is driven so that it can be transported.

  FIG. 6 is a schematic perspective view of the lateral duct 52 and the collected toner box 30. The horizontal duct 52 is provided with receiving ports 54Y and 54K that are openings for receiving residual toner from the Y / K vertical ducts 51Y and 51K. The Y / K vertical ducts 51Y and 51K are joined to the horizontal duct 52 so as to communicate with the receiving ports 54Y and 54K. The collection toner box 30 has a collection port 31 connected to the horizontal duct 52, and the inside of the horizontal duct 52 communicates with the inside of the collection toner box 30 through the collection port 31.

  In the present embodiment, with the above-described configuration, the residual toner removed from the Y / K photoconductors 1Y and 1K by the Y / K cleaning devices 6Y and 6K is finally collected in the same collection toner box 30. The

  The collected toner box 30 is detachable from the apparatus main body 110 independently of the cartridges 10Y, 10M, 10C, and 10K (that is, the photoreceptor 1 and the cleaning blade 61 of each cartridge 10). When the recovery toner box 30 is attached to the apparatus main body 110, the recovery port 31 is connected to the horizontal duct 52. The residual toner collected in the collected toner box 30 is discarded when the collected toner box 30 is replaced.

5. Replacement of Cartridge and Recovery Toner Box Next, replacement of the cartridge 10 and the recovery toner box 30 will be described.

  In this embodiment, the replacement time of the cartridge 10 is determined by the rotation time of the photosensitive member 1 and the toner consumption. Any information that correlates with the amount of use of the photoconductor 1, such as the number of rotations, is not limited to the rotation time of the photoconductor 1. Similarly, any information that correlates with the amount of toner in the developing device 4 such as the remaining amount of toner, as well as the toner consumption amount, can be used. That is, the control unit 120 (FIG. 1) sequentially updates the accumulated rotation time and toner consumption of each photoconductor 1 in each cartridge 10 and stores them in a storage unit (not shown). The control unit 120 recognizes that the cartridge 10 has reached the replacement time when the rotation time of each photoconductor 1 or the cumulative value of the toner consumption reaches a preset threshold value. The control unit 120 is either one of the display device 130 (FIG. 1) disposed in the apparatus main body 110 or an external device display device (not shown) connected to be communicable with the image forming apparatus 100. The user is notified that the cartridge 10 has reached the replacement time. The external device is a personal computer or the like in which a user operates the image forming apparatus 100 via a driver installed therein.

  On the other hand, the replacement timing of the collected toner box 30 is determined based on the detection result of the detection unit that detects that the capacity of the toner stored in the collected toner box 30 has reached a predetermined capacity. That is, in this embodiment, as shown in FIG. 1, the apparatus main body 110 is provided with an optical sensor 80 as a detecting means. Further, in this embodiment, the recovery toner box 30 has a detection unit (detection) that enables the optical sensor 80 to detect the toner accumulated up to a predetermined position in the recovery toner box 30 based on the presence or absence of reflection of detection light. Window) 32 is provided. Thus, the control unit 120 recognizes from the detection result of the optical sensor 80 that the toner capacity in the collected toner box 30 has reached a predetermined capacity (the collected toner box 30 has reached the replacement time). Then, the control unit 120 notifies the user that the collected toner box 30 has reached the replacement time, using the same means as in the case of replacement of the cartridge 10.

  In this embodiment, an operator such as a user who has received the notification as described above, as shown in FIG. 7A, is a front cover 140 provided on the front surface of the apparatus main body 110 (the front side in FIG. 1). Open. As a result, as shown in FIG. 7B, the unit (cartridge 10 or recovered toner box 30) that has reached the replacement time can be replaced with a new one.

6). Effects Next, the effects of the present embodiment will be described by comparing the present embodiment with a comparative example. In the comparative example, elements having the same or corresponding functions or configurations as those in this embodiment will be described with the same reference numerals.

  FIG. 10 is a schematic cross-sectional view of the image forming apparatus 100 of the comparative example. In the image forming apparatus 100 of the comparative example, in all the image forming units PY, PM, PC, and PK, the residual toner removed from the photoreceptor 1 by the cleaning blade 61 is finally put in the cleaning container 62 as a collection container. It is configured to be collected. That is, in the image forming apparatus 100 of the comparative example, all the cleaning devices 6Y, 6M, 6C, and 6K have the same configuration as the M / C cleaning devices 6M and 6C in the present embodiment. The image forming apparatus 100 of the present embodiment and the image forming apparatus 100 of the comparative example are substantially the same in other respects.

  The capacities of the MC cleaning containers 62M and 62C in this example and all the cleaning containers 62Y, 62M, 62C, and 62K in the comparative example were set to 300 cc. This is because during the life of the cartridge 10 (10,000 sheets of image formation) when printing is repeated with a printing rate (image area ratio) of 5% for each color and a ratio of the full color mode to the mono mode of 1: 1. The capacity is sufficient to accommodate the remaining toner in each cleaning container 62. The lifetime of the cartridge 10 is set in consideration of the amount of toner consumed, the amount of wear of the photosensitive member 1, the cleaning blade 61, and the developing roller 41.

  Then, in the full color mode, the time when the Y cartridge 10Y was in a state to be replaced when the blue image was repeatedly printed as a test image at a printing rate of 100% for each color of magenta and cyan was confirmed.

  As a result, in this embodiment, the Y cartridge 10Y could be used for the set lifetime (10,000 sheets of images). In this embodiment, although Y toner is not consumed, the Y cartridge 10 is in a state where replacement is desired when the number of formed images is 10,000 due to wear of the photosensitive member 1, the cleaning blade 61, and the developing roller 41. It was.

  On the other hand, in the comparative example, the Y cartridge 10Y is in a state to be replaced when the cumulative number of images formed is 250, which is earlier than the set life of the Y cartridge 10Y. In the comparative example, the residual toner on the intermediate transfer belt 7 is accommodated in the Y cleaning container 62Y, and unlike the present embodiment, the Y cleaning container 62Y is the final collection location. Since the test image is formed in two colors with a printing rate of 100%, a large amount of toner remains on the intermediate transfer belt 7, and this is collected in a concentrated manner in the Y cleaning container 62Y. Therefore, in the comparative example, the Y cleaning container 62Y was filled with the remaining toner at the time when the number of formed images was as small as 250 sheets, and the Y cartridge 10Y was in a state to be replaced.

  Similarly, the time when the K cartridge 10K was in a state to be replaced when a black image was repeatedly printed as a test image at a printing rate of 100% in the mono mode was confirmed. As a result, as in the case of the full color mode, in this embodiment, the K cartridge 10K could be used for the set lifetime. On the other hand, in the comparative example, the K cleaning container 62K is full of the remaining toner, and the K cartridge 10K is in a state to be replaced earlier than the set life.

  In order to be able to use the Y · K cartridges 10Y and 10K for the life set by the usage amount of the photoreceptor 1 under the conditions as described above, the capacities of the Y · K cleaning containers 62Y and 62K are used. It is conceivable to increase However, in this case, the Y / K cartridges 10Y and 10K are increased in size, and the image forming apparatus 100 is easily increased in size.

  It is also conceivable that the Y / K cleaning containers 62Y, 62K are separated from the other elements of the Y / K cartridges 10Y, 10K, and can be individually replaced when the remaining toner is full. . However, in that case, the configuration of the image forming apparatus 100 becomes complicated, and usability decreases.

  On the other hand, in the configurations of the present embodiment and the comparative example, the residual toner on the intermediate transfer belt 7 is not collected in the M / C cleaning containers 62M and 62C. Therefore, the M / C cleaning containers 62M and 62C are filled with the remaining toner, and the M / C cartridges 10M and 10C are not in a state to be replaced earlier than the set lifetime.

  In general, it is rare that the image forming apparatus 100 is in a use state as in the above-described test in the market. However, it can be seen from the above-described test that the configuration of this example is effective even under the conditions as described above.

  As described above, according to this embodiment, it is not necessary to increase the capacity of the cleaning container 62 to which the residual toner on the intermediate transfer belt 7 is sent intensively. Therefore, the image forming apparatus 100 can be downsized. Further, according to the present embodiment, the cleaning container 62 provided corresponding to each photoconductor 1 can be individually attached to and detached from the apparatus main body 110 as compared with the case where the cleaning container 62 is separated from the other elements of each cartridge 10. The number of collection containers can be reduced. As a result, the configuration of the image forming apparatus 100 can be simplified, and a decrease in usability can be suppressed. Furthermore, according to this embodiment, the capacity of the collection toner box 30 that is a collection container for finally collecting the residual toner on the intermediate transfer belt 7 can be increased without increasing the size of the image forming apparatus 100. it can. This is because the collected toner box 30 does not need to be arranged around the photoreceptor 1 where many process devices are arranged, and can be arranged in an arbitrary space.

[Example 2]
Next, another embodiment of the present invention will be described. The basic configuration and operation of the image forming apparatus of this embodiment are the same as those of the first embodiment. Accordingly, in the image forming apparatus of the present embodiment, elements having the same or corresponding functions or elements as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof is omitted.

  FIG. 8 is a schematic cross-sectional view of the image forming apparatus 100 of the present embodiment. In the image forming apparatus 100 of the present embodiment, the residual toner removed from the photosensitive member 1 by the cleaning blade 61 in all the image forming units PY, PM, PC, and PK is temporarily stored in the cleaning container 62 as a temporary collection container. Be contained. The residual toner once accommodated in the cleaning container 62 passes through the vertical duct 51 (51Y, 51M, 51C, 51K) and the horizontal duct 52 constituting the conveyance unit 50, and the recovered toner as a common recovery container. Finally, it is collected in the box 30. That is, in the image forming apparatus 100 of the present embodiment, all the cleaning devices 6Y, 6M, 6C, and 6K have the same configuration as the Y / K cleaning devices 6Y and 6K in the first embodiment.

  In this embodiment, all the cartridges 10 may be provided with a cleaning container 62 as a temporary collection container that can be made smaller than the cleaning container 62 as a collection container. Therefore, it is possible to reduce the size of all the cartridges 10 and improve the usability when replacing them.

[Example 3]
Next, another embodiment of the present invention will be described. The basic configuration and operation of the image forming apparatus of the present embodiment are the same as those of the first and second embodiments. Accordingly, in the image forming apparatus of the present embodiment, elements having the same or corresponding functions or elements as those in the first and second embodiments are denoted by the same reference numerals as those in the first and second embodiments, and detailed description thereof is omitted. .

  In the present embodiment, as in the second embodiment, all the cleaning devices 6Y, 6M, 6C, and 6K have the same configuration as the Y / K cleaning devices 6Y and 6K in the first embodiment. In this embodiment, as shown in FIG. 9, the developing container 42 of the cartridge 10 disposed adjacent to the empty space by configuring the cleaning container 62 as a temporary recovery container instead of the final recovery container. Is overhanging. FIG. 9 shows a schematic cross section of the C / K cartridges 10C and 10K as a representative. In this embodiment, all the cartridges 10Y, 10M, 10C, and 10K are substantially the same except for the color of the toner. It has a configuration.

  That is, in this embodiment, the residual toner removed from the photoreceptor 1 by the cleaning blade 61 is conveyed to the rear of the apparatus main body 110 by the container screw 63. This makes it possible to effectively use the space below the cleaning blade 61 that had to be provided relatively large when the cleaning container 62 is the final recovery container. Therefore, the developing container 42 of the cartridge 10 disposed adjacent to the space can be enlarged and disposed.

  As described above, at least one photosensitive member 1 disposed adjacent to the upstream side of the photosensitive member 1 corresponding to the developing device 4 is the recovery target photosensitive member 1 whose residual toner is recovered in the recovery toner box 30. One developing device 4 can be configured as follows. That is, at least a part of the developing container 42 that forms the toner accommodating portion can be arranged at a position overlapping with the cartridge 10 including the photosensitive member 1 arranged adjacent thereto in the gravity direction. .

  According to the present embodiment, since the capacity of the toner accommodated in the developing container 42 can be increased by enlarging the developing container 42, it is possible to extend the life of the cartridge 10 due to toner consumption. Further, since the above-described space is effectively used, the developing container 42 can be enlarged without increasing the size of the image forming apparatus 100, and the toner storage capacity can be increased.

[Others]
As mentioned above, although this invention was demonstrated according to the specific Example, this invention is not limited to the above-mentioned Example.

  In the above-described embodiments, the image forming apparatus can execute the full color mode and the mono mode, and the image carrier on which the residual toner on the intermediate transfer member is intensively moved is the image carrier for yellow and black. I explained a case. However, the image forming apparatus is not limited to this, and the image forming apparatus may have any number of image forming modes in which toner images are formed on one different image carrier (or a plurality of image carriers in different combinations). May be feasible. As in the above-described embodiments, among the image carriers on which toner images are formed in the respective image forming modes, the image carrier that is disposed at the most upstream position in the moving direction of the intermediate transfer member has a residual image on the intermediate transfer member. It is easy for toner to concentrate and move. Therefore, the residual toner removed from the image carrier by the cleaning member can be finally collected in a common collection container that can be attached to and detached from the apparatus main body.

  Further, the image forming apparatus is not limited to a configuration capable of executing a plurality of image forming modes with different image carriers on which the residual toner on the intermediate transfer member is intensively moved. For example, in one image forming mode, it is considered that the residual toner on the intermediate transfer member is moved to and collected not only by one image carrier but also by two or more predetermined image carriers. It is done. In this case, the residual toner on the intermediate transfer member is intensively moved to two or more image carriers in one image forming mode. In this case, the residual toner removed from the two or more image carriers by the cleaning member can be finally collected in a common collection container that can be attached to and detached from the apparatus main body. In addition, when the residual toner removed by the cleaning member from all the image carriers is finally collected in a common collection container, the residual toner on the intermediate transfer member can be used as an arbitrary image carrier. It may be adapted to be moved to the body.

  That is, in the image forming apparatus to which the present invention is applied, the toner remaining on the intermediate transfer member after the secondary transfer is charged by the charging unit, moved to the image carrier, and removed by the corresponding cleaning member. The image forming apparatus includes a common collection container that collects toner removed from at least two of the plurality of image carriers by a corresponding cleaning member. The collection container is configured to be detachable from the apparatus main body of the image forming apparatus independently of the plurality of image carriers and the plurality of cleaning members. Typically, the image carrier that moves the toner charged by the charging means is a predetermined image carrier of the plurality of image carriers, and the collection container corresponds to at least the predetermined image carrier. The toner removed by the cleaning member is collected. Typically, there are at least two predetermined image carriers. One of the predetermined image carriers is an image carrier arranged at the most upstream position in the moving direction of the intermediate transfer member among the plurality of image carriers. In the other predetermined image carrier, a toner image is formed on the other one of the plurality of image carriers, but a toner image is formed on the other image carriers. An image carrier on which a toner image is formed in a predetermined mode in which the toner image is not formed. In other words, the other one image carrier has a toner image on the image carrier disposed upstream of the other image carrier among the plurality of image carriers in the moving direction of the intermediate transfer member. An image carrier on which a toner image is formed in a predetermined mode in which is not formed. However, the recovery container may recover the toner removed by the corresponding cleaning member from the image carrier other than the predetermined image carrier among the plurality of image carriers. The toner removed from all of the toner may be collected.

DESCRIPTION OF SYMBOLS 1 Photoconductor 4 Developing device 6 Cleaning device 7 Intermediate transfer belt 15 Cleaning brush 30 Recovery container 50 Conveying part 61 Cleaning blade 62 Cleaning container

Claims (9)

Each of a plurality of image carriers that carry a toner image, an intermediate transfer member that conveys a toner image primarily transferred from the plurality of image carriers for secondary transfer to a transfer material, and a plurality of image carriers A cleaning member for removing toner on the corresponding image carrier, and charging means for charging the toner on the intermediate transfer member,
In the image forming apparatus in which the toner remaining on the intermediate transfer member after the secondary transfer is charged by the charging unit, moved to the image carrier, and removed by the corresponding cleaning member.
A common collection container for collecting toner removed by the corresponding cleaning member from at least two of the plurality of image carriers.
The image forming apparatus, wherein the collection container is detachable from an apparatus main body of the image forming apparatus independently of the plurality of image carriers and the plurality of cleaning members.   The image carrier for moving the toner charged by the charging means is a predetermined image carrier among the plurality of image carriers, and the collection container corresponds to at least the predetermined image carrier. The image forming apparatus according to claim 1, wherein the toner removed by the cleaning member is collected.   The image forming apparatus according to claim 2, wherein the predetermined number of image carriers is at least two.   One of the predetermined image carriers is an image carrier that is disposed on the most upstream side in the moving direction of the intermediate transfer member among the plurality of image carriers, and the other one of the predetermined image carriers. One is that a toner image is formed in a predetermined mode in which a toner image is formed on the other one of the plurality of image carriers but a toner image is not formed on the other image carriers. The image forming apparatus according to claim 3, wherein the image forming apparatus is an image carrier.   One of the predetermined image carriers is an image carrier that is disposed on the most upstream side in the moving direction of the intermediate transfer member among the plurality of image carriers, and the other one of the predetermined image carriers. One of the plurality of image carriers is a toner image in a predetermined mode in which a toner image is not formed on the image carrier disposed upstream of the other one image carrier in the moving direction of the intermediate transfer member. The image forming apparatus according to claim 3, wherein the image forming apparatus is an image carrier on which is formed.   6. The collection container collects toner removed by the corresponding cleaning member from the image carrier other than the predetermined image carrier among the plurality of image carriers. The image forming apparatus according to claim 1.   The image forming apparatus according to claim 6, wherein the collection container collects toner removed by the corresponding cleaning member from all of the plurality of image carriers.   8. Each of the plurality of image carriers and the corresponding cleaning member constitutes a cartridge that can be integrally attached to and detached from the apparatus main body. The image forming apparatus described in the item. A plurality of developing devices that are provided corresponding to each of the plurality of image carriers and that supply toner to the corresponding image carriers to form a toner image, each of which includes a storage unit that stores the toner. A plurality of developing devices,
9. The image according to claim 8, wherein the developing device has at least a part of the accommodating portion disposed at a position overlapping with the cartridge including the image carrier disposed adjacent to the developing device in a direction of gravity. Forming equipment.

Images