Cleaning apparatus and process cartridge

Abstract: This invention relates to a cleaning container (14) having a highly durable drum in which removed toner is efficiently accumulated by toner conveyance having a backflow preventive function and upward conveyance, and optical fill-up detection (58) is provided for detecting the container is full of removed toner before malfunction is caused. The cleaning container (14) is divided in three chambers, a cleaning chamber (43), a removed toner accumulating chamber (44) and an intermediate conveying chamber by one partition plate (41). In the cleaning chamber (43) toner is conveyed with a screw (45), and in the intermediate conveying chamber, toner is conveyed upward by a cylindrical impeller having ribs, openings and protrusions on its outer periphery, a toner receptacle and a conveying guide. In removed toner small chambers partitioned with partition ribs, toner is stored from the upstream side with a screw partially having a reversed helical configuration, and in the small chamber at the most downstream side, the fill-up is optically detected. A cleaning member (56) for fill-up detecting windows (54,55) cleans in order of a top face window, then a side face window, and has ribs for preventing toner from flowing in at both sides of the windows.

Description: BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a process cartridge used in an electrophotographic image forming apparatus. Here, the electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming system. Examples of the electrophotographic image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (e.g. a laser beam printer, an LED printer or the like), a facsimile device, a word processor and the like. For the process cartridge, at least a cleaning means and an electrophotographic photosensitive body are formed integrally into a cartridge. The cartridge is detachably attached to a main body of an image forming apparatus. Since a user can attach or detach the cartridge to or from the main body, the main body can be easily maintained. Related Background Art In a conventional image forming apparatus using an electrophotographic image forming process, an electrophotographic photosensitive body and a process means acting on the electrophotographic photosensitive body are formed integrally into a cartridge. The cartridge is detachably attached to a main body of an image forming apparatus. In this process cartridge system, since a user itself can maintain the apparatus without depending on a serviceman, operability can be remarkably enhanced. Therefore, the process cartridge system is widely used in the image forming apparatus. A developing unit is separated from a process cartridge for an image forming process in which an electrophotographic photosensitive body, a charging means and a cleaning means are integrally formed. The units can be easily detachably mounted on a main body, and used in compliance with the lifetime of each main component. In the process cartridge, removed toner resulting from cleaning is stored in a cleaning container having a sufficient storage volume to conform with the lifetime of the electrophotographic photosensitive body. When replacing the process cartridge, the cleaning container is also removed. JP-A-8-129329 discloses a cleaning device for an image carrier, wherein toner is removed from the image carrier in a first compartment, and a conveyor moves the toner to an exit from the first compartment. The toner exiting the first compartment enters a second, storage compartment, wherein a second conveyor moves the toner into the interior of the second compartment. An object of the invention is to provide a cleaning apparatus, and a process cartridge incorporating the cleaning apparatus, which can contain the removed toner effectively. Another object is to provide a cleaning apparatus and process cartridge which can extend the lifetime thereof. Still another object is to provide a cleaning apparatus and a process cartridge which can maintain the cleaning ability longer than the conventional art. Still another object is to provide a cleaning apparatus and a process cartridge in which the toner in the first chamber is fed to the opened portion by the toner convey member and then to the second chamber. According to the present invention, there is provided a cleaning apparatus as defined in claim 1. A further aspect of the invention provides a process cartridge as claimed in claim 18. Embodiments of the invention will now be described in detail with reference to the accompanying drawings, in which: Fig. 1 is a longitudinal sectional view of a color laser printer according to a first embodiment of the present invention. Fig. 2 is a longitudinal sectional view of a process cartridge according to the first embodiment. Fig. 3 is a horizontal sectional view of the process cartridge seen from above according to the first embodiment. Fig. 4 is a horizontal sectional view of the process cartridge seen from above according to the first embodiment. Fig. 5 is a horizontal sectional view of the process cartridge seen from above according to the first embodiment. Fig. 6 is a horizontal sectional view of a process cartridge seen from above according to a second embodiment of the invention. Fig. 7 is a horizontal sectional view of a process cartridge seen from above according to a third embodiment of the invention. Fig. 8 is a longitudinal sectional view of the process cartridge seen from above according to the third embodiment. Fig. 9 is a perspective view showing an upward conveying constitution according to the third embodiment. Fig. 10 is a longitudinal sectional view of a process cartridge using another conveying member according to the invention. Fig. 11 is a longitudinal sectional view of a process cartridge using another conveying member according to the invention. Fig. 12 is a longitudinal sectional view of a process cartridge using another conveying member according to the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention are now described with reference to accompanying drawings. In the following description, a short direction of a process cartridge B coincides with a conveying direction of a recording medium. Also, a longitudinal direction of the process cartridge B is a direction in which the process cartridge B is detachably attached to a main body 13, parallel with a surface of the recording medium, and intersecting (substantially orthogonal to) the conveying direction of the recording medium. Further, left and right relative to the process cartridge indicate the left and the right of the recording medium seen from above along the conveying direction of the recording medium. EMBODIMENT 1 [Entire Constitution of Image Forming Apparatus] The entire constitution of the image forming apparatus is first described referring to Fig. 1. Fig. 1 is an explanatory view of an entire constitution of a laser beam printer as a color image forming apparatus. The color laser printer is, as shown in Fig. 1, provided with an image forming portion constituted of an image carrier 15 rotating at a constant rate, a fixed black developing unit 21B and three rotatable color developing units 20Y, 20M and 20C, and an intermediate transfer body 9 for holding a color image developed by the image forming portion and transferred in multiplicity and further transferring the color image onto a transfer material 2 as the recording medium supplied from a supply portion. The transfer material 2 with the color image transferred thereon is then conveyed to a fixing portion 25 to fix the color image on the transfer material 2, and discharged via discharge rollers 34, 35 and 36 to a discharge tray 37 on a top face of the device. The rotatable color developing units 20Y, 20M and 20C and the fixed black developing unit 21B are separately detachably attached to the main body 13. The constitution of each portion of the image forming apparatus is successively described. [Electrophotographic Photosensitive Drum Unit] The process cartridge B is constituted integrally with an electrophotographic photosensitive drum 15 and a cleaning container 14 also serving as a holder of the photosensitive drum 15. The process cartridge B is detachably attached and supported relative to the main body 13, and can be easily replaced as a unit in accordance with the lifetime of the photosensitive drum 15. The photosensitive drum 15 of the embodiment is constituted by applying an organic photo-conductive layer to an outer periphery of an aluminum cylinder having a diameter of about 60mm, and rotatably supported by the cleaning container 14 also serving as the holder of the photosensitive drum 15. On the periphery of the photosensitive drum 15, a cleaning blade 16 and a primary charging means 17 are arranged. By transmitting a drive force of a drive motor (not shown) to one rear end as seen in Fig. 1, the photosensitive drum 15 is rotated counterclockwise in response to image forming operation. [Charging Means] The charging means 17 uses a contact charging method, in which a conductive roller is in contact with the photosensitive drum 15. By applying voltage to the conductive roller, a surface of the photosensitive drum 15 is uniformly charged. [Exposure Means] The photosensitive drum 15 is exposed from a scanner portion 30. Specifically, when an image signal is given to a laser diode, the laser diode radiates an image beam corresponding to the image signal to a polygonal mirror 31. The polygonal mirror 31 is rotated at high speeds by a scanner motor. The image beam reflected by the polygonal mirror 31 is exposed via an imaging lens 32 and a reflective mirror 33 selectively to the surface of the photosensitive drum 15 rotating at a constant speed. As a result, an electrostatic latent image is formed on the photosensitive drum 15. [Developing Means] To visualize the electrostatic latent image, a developing means is constituted of three rotary developing units 20Y, 20M and 20C and one black developing unit 21B for developing in color of yellow, magenta, cyan and black, respectively. The black developing unit 21B is a fixed developing unit. A sleeve 21BS is disposed opposite to the photosensitive drum 15 with a micro interval (about 300 µm) from the photosensitive drum 15, to form a visual image with black toner on the photosensitive drum 15. In the black developing unit 21B, toner in the container is fed by a feeder mechanism. An application blade 21BB in contact under pressure with an outer periphery of the developing sleeve 21BS applies a thin layer of toner onto the outer periphery of the developing sleeve 21BS rotating clockwise in Fig. 1, while giving an electric charge (frictional electrification) to the toner. By applying a developing bias to the developing sleeve 21BS, toner is developed corresponding to the electrostatic latent image on the photosensitive drum 15. Three rotary developing units 20Y, 20M and 20C are detachably supported by a developing rotary 23 dividing and rotating about a rotary rotation axis 22, respectively. When forming an image, the developing units held by the developing rotary 23 are rotated and moved centering on the rotary rotation axis 22. The specified one of the developing units is stopped at a position opposed to the photosensitive drum 15. Further, either one of developing sleeves 20YS, 20MS and 20CS is positioned opposite to the photosensitive drum 15 with a micro interval (about 300 µm), and a visual image is formed corresponding to the electrostatic latent image on the photosensitive drum 15. When forming a color image, every time the intermediate transfer body 9 is rotated once, the developing rotary 23 is rotated to perform a developing process in order of the yellow developing unit 20Y, the magenta developing unit 20M, the cyan developing unit 20C, subsequently the black developing unit 21B. Fig. 1 shows that the yellow rotary developing unit 20Y is positioned and stands still opposite to the process cartridge B. In the rotary developing unit 20Y, the toner in the container is fed by the feeder mechanism to an application roller 20YR. The application roller 20YR rotating clockwise in Fig. 1 and an application blade 20YB in contact under pressure with an outer periphery of a developing sleeve 20YS apply a thin layer of toner to the outer periphery of the developing sleeve 20YS rotating clockwise, while giving an electric charge (frictional electrification) to the toner. By applying a developing bias to the developing sleeve 20YS opposed to the photosensitive drum 15 with a latent image formed thereon, the toner is developed in accordance with the latent image on the photosensitive drum 15. For the magenta developing unit 20M and the cyan developing unit 20C, toner is developed in the same mechanism as aforementioned. The developing sleeves 20YS, 20MS and 20CS of the rotary developing units 20Y, 20M and 20C are, when rotated and moved to a developing position, connected to respective color developing high-voltage power sources and drives provided in the main body 13. The developing units are successively and selectively provided with a voltage and connected to the drives, respectively. [Intermediate Transfer Body] At the time of color image forming operation, to receive multiple transfers of a toner image four times (images of four colors Y, M, C and B) visualized by the developing units 20Y, 20M and 20C on the photosensitive drum 15, the intermediate transfer body 9 is rotated clockwise synchronously with the speed of the outer periphery of the photosensitive drum 15. The intermediate transfer body 9 having received multiple transfers, together with a transfer roller 10 with a voltage applied thereto, holds and conveys the transfer material 2, so that each toner image on the intermediate transfer body 9 is concurrently transferred in multiplicity to the transfer material 2. The intermediate transfer body 9 of the embodiment is constituted by covering the outer periphery of an aluminum cylinder 12 having a diameter of 180mm with a resilient layer 11 of an intermediate resistance sponge, an intermediate resistance rubber or the like. The intermediate transfer body 9 is rotatably supported and driven by an integrally fixed gear (not shown) to rotate. [Cleaning Means] After the toner image visualized on the photosensitive drum 15 is transferred to the intermediate transfer body 9, the cleaning means collects toner remaining on the photosensitive drum 15. The collected removed toner is stored in the cleaning container 14. In the embodiment, as shown in Fig. 2, for a moving direction of the periphery of the photosensitive drum 15, at the upstream side of a cleaning blade 16 a periphery of a cleaning roller 60 is slid with friction and moved while rotating in a reverse direction of the moving direction of the periphery of the photosensitive drum 15. The cleaning container 14 is integrally replaced at the same time when the photosensitive drum 15 is replaced at the expiry of its lifetime or complete full by the removed toner. The constitution of the cleaning container 14 is detailed later. [Sheet Supply Portion] The sheet supply portion supplies the transfer material 2 to the image forming portion, and is constituted mainly of a sheet supply cassette 1 containing plural sheets of transfer material 2, a sheet supply roller 3, a feed roller 4, a retard roller 5 for preventing overlapped sheet supply, a sheet supply guide 6 and a regist roller 8. When forming an image, the sheet supply roller 3 is driven and rotated in response to image forming operation, so that the transfer material 2 is supplied separately sheet by sheet from the sheet supply cassette 1, guided via the sheet supply guide 6 and conveyed via a conveying roller 7 to the regist roller 8. During the image forming operation, the regist roller 8 performs a nonrotating operation for stopping the transfer material 2 on standby and a rotating operation for conveying the transfer material 2 to the intermediate transfer body 9 in a predetermined sequence, and, at the subsequent transfer process, aligns an image with the transfer material 2. [Transfer Portion] The transfer portion is constituted of the swingable transfer roller 10 constituted of a metallic axis wound with an intermediate resistance foam resilient material, is movable vertically as shown in Fig. 1 and driven by a drive source. When four-color toner images are formed on the intermediate transfer body 9, i.e. when the intermediate transfer body 9 is rotated plural times, not to disturb the images, as shown by a solid line, the transfer roller 10 is positioned below and distant from the intermediate transfer body 9. Upon formation of the four-color images on the intermediate transfer body 9, in accordance with a timing when a color image is transferred to the transfer material 2, the transfer roller 10 is moved to an upper position shown by a thin line by a cam member (not shown), i.e. pushed against the intermediate transfer body 9 via the transfer material 2 with a predetermined pressure. At the same time, a bias is applied to the transfer roller 10, and the toner image on the intermediate transfer body 9 is transferred to the transfer material 2. Here, since the intermediate transfer body 9 and the transfer roller 10 are respectively driven, the transfer material 2 held between these undergoes the transfer process, and is simultaneously conveyed at a predetermined speed to the left in Fig. 1 toward the fixing portion 25 at the subsequent process. [Fixing Portion] The fixing portion 25 fixes the toner image transferred by the developing means 20 and 21 via the intermediate transfer body 9 onto the transfer material 2. As shown in Fig. 1, the fixing portion 25 is constituted of a fixing roller 26 for applying heat to the transfer material 2 and a pressure roller 27 for placing the transfer material 2 in contact with the fixing roller 26 under pressure. The rollers 26 and 27 are hollowed, have inside heaters 28 and 29, respectively, and are rotated and driven to convey the transfer material 2 at the same time. Specifically, the transfer material 2 holding the toner image is conveyed by the fixing roller 26 and the pressure roller 27, while given heat and pressure, so that the toner image is fixed on the transfer material 2. [Cleaning Container] The cleaning container 14 is detailed with reference to Figs. 2 and 3. The cleaning container 14 is provided with a partition member 41 for dividing the container into two, i.e., a cleaning chamber 43 and a removed toner accumulating chamber 44. In the vicinity of the partition member 41 disposed is a rotating screw 45 for moving the toner parallel a longitudinal direction of the photosensitive drum 15. In the vicinity of a conveying terminal end of the screw 45, an opening 46 is provided in the partition member 41. In the vicinity of the opening 46, the screw 45 has an outer periphery surrounded by a constant length of a pressure wall 42. In the cleaning chamber 43 the photosensitive drum 15 is cleaned with the cleaning blade 16 and the cleaning roller 60. According to the embodiment, in the cleaning container 14, the cleaning roller 60 abuts on the photosensitive drum 15 and rotates counterclockwise to frictionally slide on the photosensitive drum 15. Below the opening 46, a rake sheet 18 abuts with a certain angle on the photosensitive drum 15. The toner on the photosensitive drum 15 passes the abutting rake sheet 18 and enters the cleaning chamber 43. The toner is scraped off by the cleaning roller 60 and finally scraped down in the container by the cleaning blade 16. After cleaning, accumulated toner is fed by the cleaning roller 60 to the rear side of the container. In the embodiment, the cleaning roller 60 is used. When the cleaning is performed only with the cleaning blade 16, however, toner can be fed rearward by a feed blade or a stirring member instead of the cleaning roller 60. When toner reaches the vicinity of the toner conveying member constituted of the rotating screw 45, by rotation of the screw 45, toner is conveyed parallel the longitudinal direction of the photosensitive drum 15. The opening 46, which is configured so as to contact a rotation range of the screw 45 and formed in the partition member 41 for dividing the cleaning container 14 into two, is positioned at the terminal end of the conveying direction of the screw 45 outside a cleaning process range 16a. Further, the pressure wall 42 is positioned so as to surround the outer periphery of the screw 45. Therefore, the fed toner has a high particle pressure in the pressure wall 42, and securely goes via the opening 46 in the partition member 41 into the removed toner accumulating chamber 44. The screw 45 is molded in a helical form, but is not restricted to a molded screw as long as it is helical. For example, the screw 45 can be formed of a spring coil or another metallic material. In the cleaning chamber 43, a small quantity of toner always exists, but applies no excess particle pressure to the cleaning portion. Therefore, a stable cleaning can always be provided. Further, the pressure wall 42 surrounds a certain constant length of the conveying means of the screw 45, thereby preventing backflow. During operation, even when the process cartridge B is attached to or detached from the main body 13 for cleaning another unit replacement device or the body 13, the toner accumulated in the removed toner accumulating chamber 44 is prevented from flowing in reverse to the cleaning chamber 43, or a large quantity of toner is prevented from flowing over the cleaning portion. Therefore, secure cleaning can be assured. Even removed toner increased in accordance with the highly durable photosensitive drum 15 or electrophotographic photosensitive drum can be securely stored. Further, when the highly durable photosensitive drum 15 having a large number of printable sheets is removed at the expiry of its service duration, a user can easily replace or exchange the drum without manually making dirty the device, because removed toner is stored in the cleaning container 14. In the embodiment, in the removed toner accumulating chamber 44, a screw 48 used as the removed toner conveying member has a longitudinal conveying direction in reverse to the conveying direction of the screw 45 in the cleaning chamber 43. The removed toner conveyed from the cleaning chamber 43 is successively conveyed by the conveying means to the removed toner accumulating chamber 44 to accumulate. In the removed toner accumulating chamber 44 disposed is the screw 48. When the accumulated removed toner reaches the screw 48, a conveying force is generated, so that toner is fed in a rotation axis direction of the screw 48 entirely into the removed toner accumulating chamber 44. As a result, removed toner resulting from the highly durable photosensitive drum 15 can be contained sufficiently in the removed toner accumulating chamber 44. Further, as shown in Fig. 5, the helical configuration in the removed toner accumulating chamber 44 is modified in order to generate a conveying force directed in reverse to a main conveying direction at an arbitrary position, by providing a constant length of helical portion 52 at one or more places. In this constitution, the reversed helical portion 52 produces a conveying force for pushing back toner in reverse to the main conveying direction. As a result, the conveyed toner starts bulging centering on a start position of the reversed helical portion 52 from the axial direction to the radial direction. When the removed toner bulging in the radial direction becomes larger than the configuration of the reversed helical portion, toner is caught by the forward helical portions and again starts to be conveyed to a longitudinal forward conveying direction of the cleaning container 14. Also, when toner reaches a start position of the next reversed helical portion 52, toner starts accumulating centering on the reached point. By providing the reversed helical portion 52 in this manner, removed toner can be efficiently accumulated in the removed toner accumulating chamber 44. Additionally, in the removed toner accumulating chamber 44, a plurality of removed toner partition ribs 53 are provided orthogonal to the rotation axis of the screw 48, to further divide the removed toner container 14 into small chambers. The removed toner chamber partition ribs 53 may be protruded from the underside of the container 14, or constituted integrally with the partition member 41 for dividing the container into the cleaning chamber 43 and the removed toner accumulating chamber 44. Alternatively, the ribs 53 can be constituted integrally with a container lid 50 on a top face of the cleaning container 14. By partitioning the removed toner accumulating chamber 44 with the removed toner chamber partition ribs 53, removed toner can be securely stored from the upstream side of the screw 48. After toner is efficiently stored sufficiently in each upstream small chamber, toner starts accumulating in small chambers at the downstream side. Therefore, removed toner can be efficiently stored in the entire volume of the container. Further, even if a user attaches or detaches the process cartridge B to or from the main body 13, the backflow preventing effect is further enhanced by each removed toner chamber partition rib 53. As a result, the process cartridge B having the highly durable photosensitive drum 15 can be stably provided. Additionally, in the embodiment, among the small chambers partitioned by the removed toner chamber partition ribs 53, a small chamber 44E at the most downstream side is provided with a removed toner fill-up detecting means. The removed toner fill-up detecting means is optically operated. Light transmitting windows 54 and 55 are provided opposite to the top face and the rear side face of the removed toner accumulating chamber 44, respectively. By transmitting light to the small chamber 44E with light emitting and receiving portions 58 outside the process cartridge B, it is detected whether or not there exists removed toner. In the embodiment by using the aforementioned removed toner conveying member, toner is conveyed finally into the small chamber 44E. When the accumulated removed toner reaches the windows of the fill-up detection means, light from the outside is interrupted by the toner, the light receiving portion detects no light, and it is detected that the container is full of removed toner. This information is transmitted to the main body 13 and displayed directly on an operation panel or a computer, thereby informing a user that the process cartridge B is to be replaced. At this time, since the cleaning chamber 43 is not filled with removed toner, no cleaning defect arises. By providing the fill-up detecting means at the most downstream portion, regardless of the lifetime of the photosensitive drum 15, the cleaning container 14 can be prevented from being full of removed toner, thereby preventing defective cleaning. The main body 13 can be prevented from malfunctioning because of leakage of removed toner. In the fill-up detecting means according to the embodiment, the fill-up detecting windows 54 and 55 are cleaned with a rotary cleaning blade 56. The rotation direction of the cleaning blade 56 is set to a container rotation direction c, such that the fill-up detecting light transmitting window 54 on the top face of the container is first cleaned, then the fill-up detecting light transmitting window 55 is wiped. Further to prevent the toner scraped off by the cleaning blade 56 from flowing in, at both sides of the fill-up detecting light transmitting windows disposed are fill-up detecting ribs 57 for preventing backflow. Even when toner is accumulated to reach the fill-up detecting windows, at first light can be transmitted by the cleaning blade 56. As aforementioned, by providing the constitution of the cleaning container 14 and the conveying method in the cleaning chamber 43 and the removed toner accumulating chamber 44 according to the embodiment, a large volume of removed toner can be accumulated to fulfill the performance of the process cartridge B. Further, there is provided the highly safe process cartridge B which can detect if the container is full of removed toner. EMBODIMENT 2 A second embodiment of a cleaning container constitution is described referring to Fig. 6. Only the respects of the second embodiment different from the first embodiment are described. The second embodiment is constituted by providing a conveying guide along the screw 48 as the conveying means in the second conveying chamber. Since the screw 48 in the removed toner accumulating chamber 44 has removed toner chamber conveying guides 51, especially at the upstream side, removed toner is efficiently conveyed, and the upstream portion of the conveying means is advantageously prevented from packing because of excessively compressed toner. Further, the removed toner chamber conveying guides 51 have a plurality of holes. The holes are positioned to include starting and ending points of a reversed helical configuration. In the removed toner accumulating chamber 44 having such constitution, toner is positively conveyed via the holes into the removed toner accumulating chamber 44, then into the subsequent small chambers. Additionally, since the removed toner chamber conveying guides 51 are disposed across the removed toner chamber partition ribs 53, toner is effectively prevented from flowing in reverse when the cleaning container 14 is tilted. Therefore, the behavior of removed toner is effectively stabilized. Also, even when the cleaning container 14 is tilted with the downstream side having the fill-up detecting means facing downward, removed toner is effectively prevented from flowing in the fill-up detecting chamber by the removed toner chamber conveying guide 51 and the removed toner chamber partition ribs 53. Even if a small quantity of toner flows in the small chamber at the most downstream side, the fill-up detection is not affected. EMBODIMENT 3 A third embodiment of a constitution of the cleaning container 14 is described with reference to Figs. 7 to 9. Only the respects different from the aforementioned embodiments are described. The third embodiment is largely different from the other embodiments in that the cleaning container 14 is partitioned by one partition member 41 shown in Figs. 7 and 8 into three chambers, i.e., the cleaning chamber 43, the removed toner accumulating chamber 44, and a third chamber or intermediate conveying chamber 47. The opening 46 from the cleaning chamber 43 into the intermediate conveying chamber 47 is positioned outside the range of cleaning process, and provided with a function of preventing backflow, thereby providing the cleaning process stabilized for a long time. Further in the third embodiment, in the third intermediate conveying chamber 47, an impeller 63 rotating in the intermediate conveying chamber 47 and an intermediate conveying guide 65 push upward the toner conveyed from the cleaning chamber 43. The impeller 63 has one or a plurality of impeller ribs 64 at a constant height in a radial direction on an outer periphery of a cylindrical rotary body, and impeller openings 66 at the upstream side of the rotation direction. In the third embodiment, the openings 66 are provided at constant intervals at the upstream side of the impeller ribs 64, and provided with protrusions 68 having a constant length. When toner starts accumulating in the intermediate conveying chamber 47, toner is laid on the impeller ribs 64 of the impeller 63 and pushed upward along the intermediate conveying guide 65. If no protrusions 68 are provided, the pushed up toner is conveyed above the rotation center of the impeller 63, then falls along the impeller ribs 64 via the impeller openings 66 into the impeller 63. In the embodiment, however, since the protrusions 68 are provided, toner is pushed up to substantially the rotation uppermost portion of the impeller 63, then falls via the impeller openings 66 into the rotary body of the impeller 63. Above the rotation center in the impeller 63, a toner receptacle 67 is positioned as high as possible within a range not interfering with the impeller 63. Fallen toner accumulates in the toner receptacle 67. The toner receptacle 67 also serves as the toner chamber conveying guide 51 of the screw 48 of the removed toner conveying member in the removed toner accumulating chamber 44. Toner starts accumulating from the upstream side in the removed toner accumulating chamber 44. According to the constitution, in the cleaning container 14, removed toner can be efficiently fed upward in the cleaning container 14. Therefore, the cleaning container 14 can be provided for accumulating removed toner more efficiently in a limited space as compared with the conventional cleaning container. Also, the intermediate conveying chamber 47 serves as a backflow preventive means to prevent toner from accumulating in the cleaning portion. OTHER EMBODIMENTS Described are embodiments in which removed toner is conveyed from the cleaning chamber 43 to the intermediate conveying chamber 47 using other conveying members. Figs. 10, 11 and 12 show modifications of the means for conveying toner from the cleaning chamber 43 to the intermediate conveying chamber 47 in the cleaning container 14 described using Figs. 8 and 9. Only the modified respects are described. In Figs. 10, 11, regarding the movement direction of the periphery of the photosensitive drum 15, at the upstream side of the cleaning blade 16, a feed blade 61 is provided parallel with the screw 45. Fig. 10 shows the feed blade 61 having an axially perpendicular cross section shaped like a cross and extending long in the axial direction. Fig. 11 shows the feed blade 61 constituted of a rotary sheet metal 61a extending long in the axial direction and a resilient soft sheet 61b fixed to a longitudinal edge of the sheet metal 61a. The feed blade receives a drive force from the main body 13 to rotate counterclockwise, thereby moving toner to the screw 45. In Fig. 12, a feed member 62 is provided at the position of the aforementioned feed blade 61. The feed member is a roller not abutting on the photosensitive drum, and operates in substantially the same manner as the feed blade 61. As aforementioned, according to the above embodiments, even when the process cartridge is attached, detached or moved for maintenance during operation, removed toner is prevented from moving from the second chamber to the first chamber. An adequate cleaning performance can always be maintained. Also, at the time of handling, toner is prevented from leaking via the opening. According to the above embodiments, the toner conveying member is arranged along the container partition member in a longitudinal direction of the first chamber, and is a screw having an end opposed to the opening. Therefore, the volume occupied by the conveying means is small, the first chamber can be made small, and the toner containing volume of the second chamber can be enlarged. According to the above embodiments, since a pressure wall for covering the screw is provided opposite to the opening, the opening is sealed from material, and leakage of removed toner is prevented and the second chamber is provided with a conveying means for conveying toner from a side having the opening in a longitudinal direction. Therefore, even an enlarged second removed toner containing volume can be filled with removed toner, and a long use is possible. According to the above embodiments, since the conveying means provided in the second chamber is a screw, toner can be fed deep in the second chamber with a simple member; and since the screw provided in the second chamber has midway a portion twisted in a reverse direction, toner can be successively stored in the second chamber. The second chamber can be filled with toner without leaving any space. According to the above embodiments, the second chamber is partitioned in a longitudinal direction by a plurality of partition members. The screw of the second chamber is passed through the partition members. Since toner accumulates successively from a small chamber partitioned with a partition member at the upstream side of a toner conveying direction of the screw, toner does not move in the second chamber when handled. According to the above embodiments, since a small chamber at the most downstream side of the toner conveying direction of the screw in the second chamber is provided with a detecting means for detecting the fill-up with removed toner, the use beyond its limitation is prevented; since a conveying guide is provided along the screw of the second chamber for guiding toner fed by the screw so that toner does not fall, toner can be securely conveyed in the longitudinal direction of the cleaning container; and the conveying guide is provided on a portion excluding the reverse twisted portion of the screw in the second chamber, toner can be successively stored in a predetermined position of the second chamber. According to the above embodiments, toner in the first chamber is fed by the toner conveying member to the opening in the container partition member, and toner fed via the opening into the third chamber is lifted up in the third chamber to be fed to the second chamber. In the cleaning container toner particles can be easily fed higher above. As a result, there is no waste space in the cleaning container, and the cleaning container per se can be prepared in a minimum required size. Different from the prior art having a limitation that the cleaning container should be formed below a cleaning place, the cleaning container can be optionally prepared in accordance with a space in a main body. According to the above embodiments, the upward conveying means provided in the third chamber is constituted of a cylindrical rotary body, a conveying guide and a fallen toner receptacle. The cylindrical rotary body has a plurality of ribs at a constant height in a radial direction on an outer periphery of a cylindrical configuration, and has an opening at the upstream side in a rotation direction of each rib. The conveying guide is positioned at a certain distance from the outer periphery of the rotary body, and is further provided with the toner receptacle in a rotation axis direction inside the rotary body and above the rotation center of the rotary body for receiving toner falling from the opening in the rotary body. Therefore, toner fed to the third chamber can be efficiently conveyed to a high position. According to the above embodiments, since the opening at the upstream side of the rotation direction of the rib on the outer periphery of the rotary body as the upward conveying means for conveying the toner upwardly is at a certain distance from the rib, more toner can be moved in an advancing direction of the rib, and toner can be conveyed higher. According to the above embodiments, since the toner receptacle of the third chamber serves as the conveying guide of the second chamber, toner can be smoothly conveyed from the third chamber to the second chamber; and the main body is prevented from malfunctioning because of using of the cleaning apparatus full of toner. According to the above embodiments, the cleaning member surely wipes from the first detecting window in the top face, thereby preventing toner from unnecessarily flowing in and maintaining a stabilized light transmitting property; and the cleaning container has ribs with a constant height from a wall of the cleaning container at both sides with a certain distance in a rotation axis direction of the cleaning member from the detecting windows. Therefore, even when toner accumulates in the portions of the detecting windows, toner is prevented from unnecessarily flowing in, and a stabilized light transmitting property can be maintained. According to the above embodiments, since the opening between the first chamber and the second chamber is outside a range of cleaning process, in all the regions in the range of cleaning process range the toner conveying member feeds toner into the opening. Even if toner resulting from the cleaning process accumulates in the vicinity of the opening, the cleaning performance is hardly affected. As mentioned above, the toner can be effectively contained, according to the present invention.

Claims: A cleaning apparatus for use in an electrophotographic image forming apparatus for removing a toner from an electrophotographic photosensitive body, the cleaning apparatus comprising: an elongate cleaning chamber (43) having cleaning means (16,60) for removing toner from an electrophotographic photosensitive body (15) and a first conveyor (45) for transporting toner to an opening (46) at one end of the cleaning chamber (43); and a removed toner accumulating chamber (44) for receiving toner; characterised by further comprising: an intermediate chamber (47) into which toner is able to pass from the cleaning chamber (43) via the opening (46), wherein the toner is able to pass to a third conveyor (48) for removing toner from the intermediate chamber and delivering the toner removed to said removed toner accumulating chamber (44). A cleaning apparatus according to claim 1, wherein said first conveyor (45) is a screw conveyor arranged longitudinally in the elongate cleaning chamber such that an end of the first conveyor (45) is adjacent to said opening (46). A cleaning apparatus according to claims 1 or 2, wherein a pressure wall (42) is provided opposite to said opening (46) and is arranged to surround the end of said first conveyor (45) adjacent to said opening (46). A cleaning apparatus according to any preceding claim, wherein said third conveyor (48) is arranged to transport the toner into the removed toner accumulating chamber (44) from the intermediate chamber (47). A cleaning apparatus according to any preceding claim, wherein said third conveyor (48) is arranged to transport toner within said removed toner accumulating chamber (44) in a transport direction extending away from said intermediate chamber (47). A cleaning apparatus according to any preceding claim, wherein said third conveyor (48) is a screw. A cleaning apparatus according to claim 6, wherein at least one axially-extending portion of the screw has a thread of opposite hand to a remaining portion of the screw. A cleaning apparatus according to any preceding claim, wherein the removed toner accumulating chamber (44) is provided with a number of partition members (53) through each of which the third conveyor (48) passes, spaced apart to provide a series of chambers along a toner transport direction of said third conveyor (48). A cleaning apparatus according to claim 8, further comprising a detecting means (58) for detecting whether a final detecting chamber (44E) in said series of chambers is full of toner. A cleaning apparatus according to any preceding claim, wherein a conveying guide (51) is provided along said third conveyor (48) in said removed toner accumulating chamber (44) for guiding toner conveyed by the third conveyor (48). A cleaning apparatus according to claim 10 when dependent on claim 7, wherein said conveying guide (51) is discontinuous, and continuous portions of the conveying guide (51) are arranged only to guide toner conveyed by the third conveyor (48) in the toner transport direction of said third conveyor (48). A cleaning apparatus according to any one of claims 2 to 11, wherein when said cleaning apparatus is positioned for use in said electrophotographic image forming apparatus, the axis of the screw of the first conveyor (45) is lower than the axis of the screw of the third conveyor (48). A cleaning apparatus according to any preceding claim, wherein a second conveyor (63) is provided in the intermediate chamber for transporting toner to the third conveyor (48). A cleaning apparatus according to claim 13, wherein the second conveyor (63) is arranged to transport the toner upwardly from a first position adjacent said opening (46) to a second position adjacent an end of said third conveyor (48), and said second conveyor (63) comprises a cylindrical rotary body having a plurality of ribs (64) for sweeping and collecting said toner, each rib extending radially from an outer periphery of the rotary body, said conveyor (63) further comprising a conveying guide (65) which surrounds said cylindrical rotary body, a fallen toner receptacle (67), and openings (66) in the periphery of the cylindrical rotary body, where said fallen toner receptacle is provided between an axis of rotation of said cylindrical rotary body and the periphery of the cylindrical rotary body such that said openings (66) are arranged to allow toner to pass from the periphery of the cylindrical rotary body, into said fallen toner receptacle. A cleaning apparatus according to claim 14, wherein said openings (66) on the outer periphery of the rotary body of the second conveyor (63) are spaced from corresponding ribs (64). A cleaning apparatus according to claim 15, wherein the fallen toner receptacle (67) of the intermediate chamber is a continuation of the conveying guide (51) of the removed toner accumulating chamber (44). A cleaning apparatus according to any preceding claim, wherein said opening (46) is beyond an end of the cleaning means (16) in said elongate cleaning chamber (43). A process cartridge for removable attachment to a main body of an electrophotographic image forming apparatus, the process cartridge comprising; an electrophotographic photosensitive body (15); and a cleaning apparatus for removing toner from said electrophotographic photosensitive body, said cleaning apparatus including: an elongate cleaning chamber (43) having cleaning means (16, 60) for removing toner from the electrophotographic photosensitive body (15), and a first conveyor (45) for transporting toner to an opening (46) at one end of the cleaning chamber (43); and a removed toner accumulating chamber (44) for receiving toner; characterised by further comprising: an intermediate chamber (47) into which toner is able to pass from the cleaning chamber (43) via the opening (46), wherein the toner is able to pass to a third conveyor (48) for removing toner from the intermediate chamber and delivering the toner removed to said removed toner accumulating chamber (44). A process cartridge according to claim 18, wherein said first conveyor (45) is a screw conveyor arranged longitudinally in the elongate cleaning chamber such that an end of the first conveyor (45) is adjacent to said opening (46). A process cartridge according to claims 18 or 19, wherein a pressure wall (42) is provided opposite to said opening (46) and is arranged to surround the end of said first conveyor (45) adjacent to said opening (46). A process cartridge according to any one of claims 18 to 20, wherein said third conveyor (48) is arranged to transport the toner into the removed toner accumulating chamber (44) from the intermediate chamber (47). A process cartridge according to any one of claims 18 to 21, wherein said third conveyor (48) is arranged to transport toner within said removed toner accumulating chamber (44) in a transport direction extending away from said intermediate chamber (47). A process cartridge according to any one of claims 18 to 22, wherein said third conveyor (48) is a screw. A process cartridge according to claim 23, wherein at least one axially extending portion of the screw has a thread of opposite hand to a remaining portion of the screw. A process cartridge according to any one of claims 18 to 24, wherein the removed toner accumulating chamber (44) is provided with a number of partition members (53) through each of which the third conveyor (48) passes, spaced apart to provide a series of chambers along a toner transport direction of said third conveyor (48). A process cartridge according to claim 25, further comprising a detecting means (58) for detecting whether a final detecting chamber (44E) in said series of chambers is full of toner. A process cartridge according to any one of claims 18 to 26, wherein a conveying guide (51) is provided along said third conveyor (48) in said removed toner accumulating chamber (44) for guiding toner conveyed by the third conveyor (48). A process cartridge according to claim 27 when dependent on claim 24, wherein said conveying guide (51) is discontinuous, and continuous portions of the conveying guide (51) are arranged only to guide toner conveyed by the third conveyor (48) in the toner transport direction of said third conveyor (48). A process cartridge according to any one of claims 19 to 28, wherein when said cleaning apparatus is positioned for use in said electrophotographic image forming apparatus, the axis of the screw of the first conveyor (45) is lower than the axis of the screw of the third conveyor (48). A process cartridge according to any one of claims 18 to 29, wherein a second conveyor (63) is provided in the intermediate chamber for transporting toner to the third conveyor (48). A process cartridge according to claim 30, wherein the second conveyor (63) is arranged to transport the toner upwardly from a first position adjacent said opening (46) to a second position adjacent an end of said third conveyor (48) and said second conveyor (63) comprises a cylindrical rotary body having a plurality of ribs (64) for sweeping and collecting said toner, each rib extending radially from an outer periphery of the rotary body, said conveyor (63) further comprising a conveying guide (65) which surrounds said cylindrical rotary body, a fallen toner receptacle (67), and openings (66) in the periphery of the cylindrical rotary body, where said fallen toner receptacle is provided between an axis of rotation of said cylindrical rotary body and the periphery of the cylindrical rotary body such that said openings (66) are arranged to allow toner to pass from the periphery of the cylindrical rotary body, into said fallen toner receptacle. A process cartridge according to claim 31, wherein said openings (66) on the outer periphery of the rotary body of the second conveyor (63) are spaced from corresponding ribs (64). A process cartridge according to claim 32, wherein the fallen toner receptacle (67) of the intermediate chamber is a continuation of the conveying guide (51) of the removed toner accumulating chamber (44). A process cartridge according to any one of claims 18 to 33, wherein said opening (46) is beyond an end of the cleaning means (16) in said elongate cleaning chamber (43).

Inventors: MORI TOMONORI, MURAYAMA KAZUNARI, MORI, TOMONORI, MURAYAMA, KAZUNARI
Applicants: CANON KK, CANON KABUSHIKI KAISHA
Application year: 1997
Main classification: G03G21
IPC codes: G03G21