Patent Publication Number: US-8526846-B2

Title: Process cartridge and image forming apparatus

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     One of the aspects of the present invention relates to a process cartridge and an image forming apparatus. The image forming apparatus of the present invention forms an image on a recording medium using electrophotographic image forming process. The image forming apparatus is, for example, an electrophotographic copying machine, an electrophotographic printer (e.g., a light-emitting diode (LED) printer, a laser beam printer), and an electrophotography facsimile apparatus. 
     The recording medium is a medium on which an image is formed and is, for example, a recording sheet, an overhead projector (OHP) sheet, or the like. Further, the process cartridge is a cartridge having a processing unit and an electrophotography photosensitive drum (hereinafter referred to as a “photosensitive drum”) integrated into one unit detachably attached to the image forming apparatus. The processing unit integrated in the process cartridge is at least one unit out of a charging unit, a developing unit, and a cleaning unit. Thus, a cartridge having at least a developing unit, as the processing unit, and a photosensitive drum integrated into one unit and is detachably attached to the image forming apparatus is included in the process cartridge. 
     2. Description of the Related Art 
     A process cartridge detachably attached to an image forming apparatus includes a cleaning unit and a developing unit. The cleaning unit generally includes a photosensitive drum and a cleaning unit. The developing unit includes a developing roller configured to supply developer to a photosensitive drum, a developer supplying unit including a developer supply roller configured to supply the developer to the developing roller, and a developer container which contains the developer. 
     The developer supplying unit and the developer container are separated by a partition. The partition is provided with an opening to connect the developer supplying unit and the developer container. Through the opening, the developer in the developer container is conveyed to the developer supplying unit by a developer conveyance member provided in the developer container. 
     When the process cartridge is in the unused state, the opening portion of the developer container is hermetically sealed by a seal member. One end of the seal member is joined to a handle member. When the user mounts the process cartridge to the image forming apparatus main body, the user pulls the handle member to remove the seal member, and the opening portion is opened. 
     In addition to the above-described configuration, there is proposed a configuration where the seal member is wound after the process cartridge is mounted to the image forming apparatus main body. According to this configuration, a winding member that winds the seal member is provided on the process cartridge. When the winding member receives a drive force from a drive source provided on the image forming apparatus main body, the winding member automatically winds up the seal member and opens the opening portion. 
     However, if the winding member that winds up the winding member of the seal member and the developer conveyance member are driven by one drive source provided on the image forming apparatus main body, the increase in the load torque of the process cartridge needs to be considered. 
     Specifically, there are two types of load torque. One is a load torque which is produced when the winding member is driven and the seal member is removed from the opening portion. The other is a load torque which is produced when the developer conveyance member is driven. In the case of the process cartridge in unused state, the developer may be clumped in the developer container due to vibration during distribution. If the developer conveyance member is driven when the developer is clumped in the developer container, a greater load torque than usual will be necessary to unwind the clumped developer. 
     Considering the load torque, if a drive source that can produce a larger torque is used in the image forming apparatus, the size of the apparatus will be increased or the cost will be increased. Thus, Japanese Patent Application Laid-Open No. 2005-077742 discusses an image forming apparatus which winds the seal member before driving the developer conveyance member when the seal member of the process cartridge in the unused state is wound automatically. 
     According to such a configuration, the timing of elevation of the load torque due to the winding of the seal member and the timing of elevation of the load torque due to the driving of the developer conveyance member can be staggered. Accordingly, the load of the drive source of the image forming apparatus can be reduced, and thus downsizing of the drive source of the image forming apparatus can be realized. This also leads to downsizing of the apparatus and cost reduction. 
     However, the conventional configuration has the following drawbacks. Generally, a cleaning unit of a process cartridge includes a cleaning member used for cleaning the surface of the photosensitive drum. The cleaning member is generally a rubber blade which is formed along the longitudinal direction of one end of a sheet metal. The rubber portion of the cleaning member abuts on the surface of the cylindrical photosensitive drum. Further, the cleaning member is arranged such that it abuts on the photosensitive drum in a direction opposite to the rotation direction. 
     If the photosensitive drum is continuously driven in a state where the developer is not on the contact portion of the photosensitive drum and the cleaning member, slide friction between the photosensitive drum and the cleaning member increases, and burrs may be generated in the rubber portion of the cleaning member. 
     However, if the image forming apparatus is a type that winds the seal member, the developer is not transmitted to the developing roller until the seal member is wound. Thus, the photosensitive drum will be rotated without the developer between the cleaning member and the photosensitive drum. Accordingly, there is threat that burrs of the cleaning member may be occurred. 
     Further, if the image forming apparatus is the type described above in which the seal member is wound before the drive of the developer conveyance member, the timing the developer is conveyed to the developing roller by the developer conveyance member further delay. This is further disadvantageous to the generation of burrs of the cleaning member. 
     Thus, according to the conventional configuration, to prevent the generation of burrs of the cleaning member when the winding of the seal member is performed, a sliding agent is applied to the cleaning member or a material that can reduce the slide friction is used on the surface of the photosensitive drum. 
     SUMMARY OF THE INVENTION 
     One of the aspects of the present invention is directed to a method for staggering a timing of elevation of the load torque due to winding of a seal member of a process cartridge in unused state and a timing of elevation of the load torque due to driving of a developer conveyance member. 
     Further, one of the aspects of the present invention is directed to a developing unit, a process cartridge, and an electrophotographic image forming apparatus which can prevent generation of burrs of a cleaning member. 
     According to an aspect of the present invention, a process cartridge mountable to and removable from an image forming apparatus main body includes an electrophotographic photosensitive member, a developing roller configured to develop an electrostatic latent image formed on the electrophotographic photosensitive member by a developer, a cleaning blade configured to remove the developer from the electrophotographic photosensitive member, a developer container including an opening through which the developer is supplied to the developing roller and configured to contain the developer, a developer conveyance member rotatably supported by the developer container and configured to convey the developer to the developing roller, a driving force transmission member having a driving force transmitted from the developer conveyance member, a seal member configured to seal the opening, and a winding member configured to wind the seal member such that the opening is opened, and the driving force transmission member is configured to take a first position at which the driving force is not transmitted to the winding member and a second position at which the driving force is transmitted to the winding member, and the driving force transmission member is further configured to move from the first position to the second position after rotation of the developer conveyance member. 
     Further features and aspects of the present invention will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments, features, and aspects of the invention and, together with the description, serve to explain the principles of the invention. 
         FIGS. 1A to 1C  are partial sectional drawings of a process cartridge to illustrate the winding operation of the seal member. 
         FIG. 2  is a cross-sectional drawing of an image forming apparatus in an image forming state according to an exemplary embodiment of the present invention. 
         FIG. 3  is an oblique perspective view of the image forming apparatus according to the exemplary embodiment. 
         FIG. 4  is an oblique perspective view of the image forming apparatus in a state where an open/close door is opened. 
         FIGS. 5A and 5B  are oblique perspective views of the process cartridge. 
         FIG. 6  is a cross-sectional drawing of the process cartridge which is in a state that imaging is possible. 
         FIG. 7  is an oblique perspective view of a mounting portion of the process cartridge of the image forming apparatus. 
         FIG. 8  is an oblique perspective view of a developer container to illustrate the configuration of winding of seal member. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Various exemplary embodiments, features, and aspects of the invention will be described in detail below with reference to the drawings. 
     First, overall configuration of the image forming apparatus will be described with reference to  FIG. 2 .  FIG. 2  is a cross-sectional drawing of the image forming apparatus of the present exemplary embodiment. The image forming apparatus is in an image forming state. 
     An image forming apparatus  1  illustrated in  FIG. 2  includes four process cartridges  11  ( 11 Y,  11 M,  11 C, and  11 K) arranged parallel with being slanted with respect to horizontal direction. Each of the process cartridges  11  can be independently detachably attached to an apparatus main body  3  of the image forming apparatus  1 . The apparatus main body  3  is the portion which is left when the process cartridge  11  is removed from the image forming apparatus  1 . 
     When a user detachably attaches the process cartridge  11  (hereinafter simply referred to as the cartridge  11 ) to the image forming apparatus  1 , the user moves the cartridge  11  in the axial direction of a photosensitive drum  12  as an electrophotographic photosensitive member. In the descriptions below, the axial direction of the photosensitive drum  12  is referred to as the longitudinal direction and the direction perpendicular to the axial direction of the photosensitive drum  12  is referred to as the lateral direction. Further, regarding the image forming apparatus  1 , the upstream side of the cartridge  11  with respect to the inserting direction is referred to as the front side and the downstream side of the cartridge  11  with respect to the inserting direction is referred to as the rear side. The inserting direction of the cartridge will be described below. The left and the right sides referred to in the present embodiment are the left and the right sides when the apparatus is viewed from the front. 
     Further, in  FIG. 2 , each of the cartridges  11 Y,  11 M,  11 C, and  11 K forms an image by a developer of each of the colors yellow, magenta, cyan, and black. These colors correspond to the color separation component colors of a full-color image. The cartridge  11  includes the photosensitive drum  12 . Further, electrophotographic processing units including a charge roller (charging unit)  13 , a developing unit  14 , and a cleaning unit  15  are arranged about the photosensitive drum  12 . Additionally, a laser scanner unit  16  is provided under the photosensitive drum  12  of the apparatus main body  3 . 
     Above the photosensitive drum  12 , there is provided an intermediate transfer belt unit (a belt-type transfer unit, a transfer conveying unit)  4 . The intermediate transfer belt unit  4  includes a secondary transfer inner roller  5  arranged on the right side of the unit, and a driven roller  6  arranged on the left side of the apparatus, a tension roller  7  arranged near the driven roller  6 , and an intermediate transfer belt  4   a  which is stretched and supported by the three rollers. The intermediate transfer belt (hereinafter, the belt)  4   a  is a flexible endless belt. The above-described three rollers  5 ,  6 , and  7  are parallelly arranged in the front/back direction corresponding to the rotation shaft line direction. A The tension roller  7  is urged and transferred upward so that tension is applied to the belt  4   a.    
     At the inside of the belt  4   a  on the lower side between the driven roller  6  and the secondary transfer inner roller  5 , there are parallelly provided four primary transfer rollers  9 , being a first to a fourth primary transfer rollers (primary transfer units), along the belt  4   a  with a predetermined interval in between from the left side to the right side in the front/back direction corresponding to the rotation shaft line direction. A portion where the belt  4   a  comes into contact with the photosensitive drum  12 , in the portion where a primary transfer roller  9  is arranged, is referred to as a primary transfer portion T 1 . A belt cleaning unit  10  is provided at the outside of a curved portion of the belt  4   a  at the driven roller  6 . Further, a secondary transfer outer roller  22  is provided at the outside of a curved portion of the belt  4   a  at the secondary transfer inner roller  5 . The portion where the belt  4   a  comes into contact with the secondary transfer outer roller  22  is referred to as a secondary transfer portion T 2 . 
     A paper cassette  17  which contains a recording medium P is set under the apparatus main body  3 . Further, a recording medium conveying unit is provided along the path from the paper cassette  17  to the upper side of the apparatus main body. The recording medium conveying unit includes a pick up roller  18  arranged above the paper cassette  17 , a separation pad  19 , a conveyance path  20 , a registration roller pair  21 , and a conveying guide  23 . These components are arranged in this order from the upstream to the downstream regarding the conveying direction of the recording medium P. 
     Next, the image forming operation is described. First, the each photosensitive drum  12  is rotated according to the image forming timing and the surface of the photosensitive drum  12  is evenly charged by the charge roller  13 . Then the each photosensitive drum  12  is selectively exposed to the laser light from the laser scanner unit  16 . Accordingly, an electrostatic latent image is formed on the photosensitive drum  12 . The developing unit  14  allows developer to adhere to the electrostatic latent image and develops the electrostatic latent image. After then, a bias having opposite polarity of the developer image, is applied to the primary transfer roller  9 . The processing above is performed for each of the photosensitive drum  12  of each station. The developer images are sequentially superimposed and transferred onto the belt  4   a , so that a full-color unfixed developer image is formed. This unfixed developer image is conveyed to the secondary transfer portion T 2  by the rotation of the belt  4   a.    
     On the other hand, the recording medium P in the paper cassette  17  is picked up one by one by the pickup roller  18  and the separation pad  19  and conveyed to the conveyance path  20 . Then, the recording medium P is conveyed to the secondary transfer portion T 2  at predetermined timing by the registration roller pair  21 . After then, by an application of a transfer bias to the secondary transfer outer roller  22 , each color developer image formed on the belt  4   a  is secondary transferred onto the recording medium P collectively. In this manner, an unfixed color image is formed on the recording medium P. Then, the recording medium P, which comes out from the secondary transfer portion T 2 , is separated from the belt  4   a  and conveyed to a fixing unit  24  along the conveying guide  23 . 
     The developer image is fixed onto the recording medium P by an application of heat and pressure by a heat roller  24   a  and a pressure roller  24   b . After then, the recording medium P is conveyed through a first discharge roller pair  25 , a conveyance path  26 , and a second discharge roller pair  27 , and finally discharged from a discharge port  28  onto a discharge tray  29  at the upper portion of the apparatus. On the other hand, after the developer image is transferred onto the belt  4   a , the photosensitive drum  12  allows the developer, which is left untransferred on the surface of the photosensitive drum  12  after the primary transfer, to be removed by a cleaning blade  70 , which is a cleaning member of the cleaning unit  15 , and prepares for the next imaging process. Similarly, after the recording medium P is separated from the belt  4   a , the belt  4   a  allows the developer, which is left untransferred on the belt  4   a  after the secondary transfer, to be removed by the belt cleaning unit  10 , and prepares for the next imaging process. 
     Next, a mounting method of the process cartridge will be described.  FIG. 3  is an oblique perspective view of the image forming apparatus  1 .  FIG. 4  is an oblique perspective view of the image forming apparatus  1  having an open/close door  2  opened and having one of the four cartridges  11  pushed in or taken out halfway. 
     As illustrated in  FIG. 3 , the image forming apparatus  1  of the present invention has a handle  2   a  provided on the open/close panel  2  which is on the front side of the image forming apparatus  1 . The user pulls the open/close door  2  in the direction of the arrow S illustrated in  FIG. 4  while holding the handle  2   a , and then replaces the cartridge  11  from an opening portion  61   a.    
     When the user mounts the cartridge, the user pushes the cartridge into the image forming apparatus  1  in the direction of the arrow T. Further, when the user removes the cartridge, the user pulls the cartridge out from the image forming apparatus  1  in the direction of the arrow U. In the following description, “front side” is the upstream of the arrow T direction and “rear side” is downstream of the arrow T direction. 
     Next, the cartridge  11  of the present embodiment will be described with reference to  FIGS. 5A ,  5 B,  6 , and  7 .  FIG. 5A  is an oblique perspective view of the rear side of the cartridge having a rear side cover member removed viewed from the mounting direction.  FIG. 5B  is an oblique perspective view of the front side of the cartridge having a front side cover member removed viewed from the mounting direction.  FIG. 6  is a cross section of the cartridge  11  mounted to the apparatus main body  3 . Image forming is possible regarding the cartridge  11  in this state.  FIG. 7  is an oblique perspective view of a cartridge mounting portion of the image forming apparatus  1 . 
     The cartridge  11 Y that contains yellow developer, the cartridge  11 M that contains magenta developer, the cartridge  11 C that contains cyan developer, and the cartridge  11 K that contains black developer have the same configuration. 
     As illustrated in  FIG. 5A , the direction of the rotation shaft line O of the photosensitive drum  12  is the longitudinal direction of the cartridge  11 . At the end of the rear side of a cleaning frame body  31  viewed from the cartridge mounting direction, there are provided a drum drive coupling  34 , a development drive coupling  35 , and a regulating portion  31   a . The drum drive coupling  34  is a drum driving force receiving unit that receives a driving force that rotates the photosensitive drum  12 . The driving force is provided from the apparatus main body  3 . The development drive coupling  35  is a developing roller driving force receiving unit that receives a driving force that rotates a developing roller  71  of the developing unit  14 . The driving force is provided from the image forming apparatus  1 . 
     As illustrated in  FIG. 6 , the cartridge  11  is separated into two units. The cleaning unit  15  includes the photosensitive drum  12 , the charge roller  13 , and a cleaning member  70 . The developing unit  14  includes the developing roller  71 . 
     The photosensitive drum  12  is rotatably set on the cleaning frame body  31  of the cleaning unit  15  via bearing members  32  ( 32 F and  32 R). Further, the developer remaining on the surface of the photosensitive drum  12  is removed by the cleaning member  70 . The removed developer falls in a removed developer container  31   a . The cleaning member  70  is formed of an L-shaped plate  70   a  with a rubber portion  70   b  integrally formed with the L-shaped plate along thereof in the longitudinal direction. As illustrated in  FIGS. 5A and 5B , the rubber portion  70   b  of the cleaning member  70  is arranged along the photosensitive drum  12  in the longitudinal direction in such a manner that the rubber portion  70   b  comes into contact with the photosensitive drum  12  in the direction opposite to the rotation direction (direction of arrow A in  FIG. 6 ) of the photosensitive drum  12 . 
     Further, as illustrated in  FIG. 7 , the image forming apparatus  1  includes a drum coupling  91  that transmits the driving force generated by a drive motor (not illustrated) being a drive source to the cleaning unit  15 . The drum coupling  91  and the drum drive coupling  34  of the cleaning unit  15  are in engagement. The drive force which is generated by the drive source and transmitted via the drum drive coupling  34  rotates the photosensitive drum  12  according to the image forming operation. 
     A charge roller bearing  36  is fixed to the cleaning frame body  31  in such a manner that it can move in the direction of the arrow B. A shaft  13   a  of the charge roller  13  is rotatably fixed to the charge roller bearing  36 . The charge roller bearing  36  is pressed against the photosensitive drum  12  by a charge roller pressure application member  37 . The charge roller  13  is driven to rotate by the rotation of the photosensitive drum  12 . 
     As illustrated in  FIG. 6 , the developing unit  14  includes the developing roller  71 , which comes into contact with the photosensitive drum  12  and rotates in the direction of the arrow C, and a development frame body  38 . The developing roller  71  is rotatably supported by the development frame body  38  via development bearing members  33 F and  33 R provided on both sides of the development frame body  38 . 
     Further, a developer supply roller  72  and a developing blade  73  are provided about the developing roller  71 . The developer supply roller  72  contacts the developing roller  71  and rotates in the direction of the arrow D. The developing blade  73  regulates the developer layer on the developing roller  71 . The development frame body  38  is separated into a developer supplying unit  38   a  and a developer container  38   b  by a partition  38   c . The developer supplying unit  38   a  includes the developing roller  71 , the developer supply roller  72 , and the developing blade  73 . The developer supplying unit  38   a  is in communication with the developer container  38   b  via an opening portion  38   d  provided in the partition  38   c . The developer container  38   b  includes a developer conveyance member  74 . The developer conveyance member  74  stirs the contained developer and conveys the stirred developer to the developer supply roller  72 . The developer conveyance member  74  rotates in the direction of the arrow E, and the developer in the developer container  38   b  is conveyed to the developer supplying unit  38   a  via the opening portion  38   d.    
     The developing unit  14  fits in holes  33 Fa and  33 Ra in the development bearing members  33 F and  33 R and is rotatably connected to the cleaning unit  15  by a shaft  75  ( 75 F and  75 R) fixed to the cleaning frame body  31 . When the image forming is performed, since the developing unit  14  is urged by a pressure spring  76 , the developing unit  14  rotates about the shaft  75  ( 75 F and  75 R), and the developing roller  71  comes into contact with the photosensitive drum  12 . 
     As illustrated in  FIG. 7 , the image forming apparatus includes a development coupling  92 . The development coupling  92  transmits the driving force transmitted from the drive motor (not illustrated) being the drive source to the development drive coupling  35  of the developing unit  14 . The development drive coupling  35  is integrally connected to the end of the rear side of the developing roller  71  mounting direction. As illustrated in  FIG. 5B , a developing roller gear  85  is integrally connected to the end of the front side of the developing roller  71  mounting direction. Further, as illustrated in  FIG. 5B , a developer supply roller gear  87  is integrally connected to the front side of the developer supply roller  72  in the cartridge  7  mounting direction. A development idler gear  86  is rotatably supported at the end of the front side of the developing unit  14  in the cartridge  7  mounting direction. 
     The rotation of the developing roller  71  is started when the drive force is transmitted from the development drive coupling  35  to the development coupling  92 . Then, as illustrated in  FIG. 5B , the drive force is transmitted from the developing roller gear  85  provided on the end of the front side of the developing roller  71  to the developer supply roller gear  87  via the development idler gear  86 . The developer supply roller gear  87  is integrally connected to the developer supply roller  72 , so that the developer supply roller  72  also rotates when the developer supply roller gear  87  rotates. In order to protect the above-described gears and the like, a front side cover member  90  that covers the gears and the like is fixed to the developing unit  14  on the front side in the cartridge  7  mounting direction. 
     Next, the drive configuration of the developer conveyance member  74  will be described. As illustrated in  FIG. 5A , a stirring idler gear  77  and a stirring gear  88  are provided on the rear side of the cartridge  11 . The development drive coupling  35  includes a gear unit  35   a  which is in engagement with the stirring idler gear  77 . The stirring gear  88  is integrally connected to the developer conveyance member  74 . The drive force received by the development drive coupling  35  is transmitted to the stirring gear  88  via the stirring idler gear  77 . Thus, when the development drive coupling  35  rotates, the developer conveyance member  74  also rotates. Further, as is the front side covered by the front side cover member  90 , a rear side cover member  93  that protects the gears and the like is also fixed to the rear side of the developing unit  14 . 
     Next, the seal configuration of the developer container  38   b  according to the present embodiment will be described with reference to  FIG. 8 . 
       FIG. 8  is an oblique perspective view of the developer container  38   b . If the cartridge is in the unused state, the opening portion  38   d  of the developer container  38   b  is sealed by a seal member  80  so that the developer in the developer container  38   b  does not spill out of the cartridge  11 . The seal member  80  is made of a sheet material and, as illustrated in  FIG. 8 , the seal is bonded to the entire perimeter of the opening portion  38   d  of the developer container  38   b  by thermal welding or vibration welding. Further, the seal member  80  is folded back at a folding portion  80   a . An end  80   b , which is the end of the folding portion, extends outward from a seal opening  38   e  provided on the front side of the developer supplying unit  38   a . Further, a seal wiping member  81  is provided on the seal opening  38   e . The seal wiping member  81  is used for removing the developer attached to the seal member  80 . 
     Next, the winding configuration of the seal member  80  according to the present embodiment will be described with reference to  FIGS. 5B ,  1 A, and  1 B.  FIG. 5B  is an oblique perspective view of the front side of the cartridge  11  in the mounting direction.  FIGS. 1A and 1B  are partial sectional drawings to illustrate the winding operation of the seal member  80 . 
     As illustrated in  FIG. 5B , the end  80   b  of the seal member  80  adheres to a winding member  82 , which is a cylindrical member, with a two-sided tape or the like. The winding member  82  is rotatably supported by a winding support unit  38   f  provided on the front side of the cartridge  11  in the mounting direction of the developer container  38 . Further, a winding gear unit  82   a  is provided on one end of the winding member  82 . Furthermore, a winding idler gear  83  is rotatably supported by the developer container  38 . The winding idler gear  83  includes an idler gear unit  83   a  and a worm gear unit  83   b . The winding gear unit  82   a  is in engagement with the worm gear unit  83   b.    
     A second stirring gear  89 , which is a driving force transmission member, is provided on the front side of the developer container  38  in the cartridge  11  mounting direction. The second stirring gear  89  is integrally connected to the developer conveyance member  74 . As illustrated in  FIG. 1A , the second stirring gear  89  is rotatably supported by an attachment portion  38   g  fixed on the developer container  38 . The attachment portion  38   g  includes a first screw portion  38   h . Additionally, a second screw portion  89   a , which corresponds to the first screw portion  38   h , is provided on the inner perimeter of the second stirring gear  89 . An urging member  84  is arranged between the developer container  38  and the second stirring gear  89 . 
     The first screw portion  38   h  and the second screw portion  89   a  are in rotatably engagement with each other. When the second stirring gear  89  rotates, as illustrated in  FIG. 1B , the second stirring gear  89  moves outward in the longitudinal direction of the development frame body  38  (in the direction of the arrow F). Further, as described above, the winding member  82  and the second stirring gear  89  are covered with the cover member  90  provided on the developing unit  14 . 
     Next, the winding operation of the seal member  80  of the present embodiment will be described with reference to  FIGS. 1A to 1C .  FIGS. 1A to 1C  are partial sectional drawings to illustrate the winding operation of the seal member  80 . 
     As illustrated in  FIG. 1A , when the cartridge  11  is in the unused state, the first screw portion  38   h  of the developer container  38  and the second screw portion  89   a  of the second stirring gear  89  are in engagement with each other. In this case, the second stirring gear  89  and the idler gear unit  83   a  of the winding idler gear  83  are not in engagement with each other. The position of the second stirring gear  89  in this case is referred to as a first position. 
     In this state, if the cartridge  11  is mounted to the apparatus main body  3 , a driving force transmitted from the drive motor (not illustrated) being the drive source of the image forming apparatus  1  rotates the developer conveyance member  74  via the development drive coupling  35 . In this case, the developer in the developer container  38   b  is stirred by the rotation of the developer conveyance member  74 . 
     The rotation of the developer conveyance member  74  is transmitted to the second stirring gear  89  which is integrally connected to the developer conveyance member  74 . After a predetermined number of rotations, as illustrated in  FIG. 1B , the second stirring gear  89  moves outward with respect to the longitudinal direction of the development frame body  38  (in the direction of the arrow F). The position of the second stirring gear  89  in this case is referred to as a second position. 
     Then, when the first screw portion  38   h  and the second screw portion  89   a  are out of engagement with each other, as illustrated in  FIG. 1C , the second stirring gear  89  moves in the direction of the arrow F by the urging force of the urging member  84  and abuts on an abutting face  90   a  at the front side cover member  90 . In this case, the second stirring gear  89  engages the idler gear unit  83   a  of the winding idler gear  83  being the drive transmission member. In this manner, the drive of the second stirring gear  89  is transmitted to the winding member  82  via the winding idler gear  83 , and the winding of the seal member  80  is started. 
     When the winding of the seal member  80  is started and the opening portion  38   d  is opened, according to the developer conveyance member  74 , the developer in the developer container  38   b  is conveyed to the developer supplying unit  38   a . The developer conveyed to the developer supplying unit  38   a  is further conveyed to the developing roller  71  via the developer supply roller  72 , and supplied to the photosensitive drum  12 . Then, the developer supplied to the photosensitive drum  12  works as a sliding agent that reduces the friction between the photosensitive drum  12  and the cleaning member  70  when the winding operation of the seal member  80  is performed. 
     As described above, the winding of the seal member is performed after the drive of the developer conveyance member is performed, so that the increase in the load torque of the cartridge can be suppressed. 
     Further, the winding of the seal is performed after the drive of the developer conveyance member, so that the developer can be supplied to the developing roller and the photosensitive drum earlier than when the drive of the developer conveyance member is performed after the winding of the seal member. The developer on the photosensitive drum serves as a sliding agent that contributes to reducing the friction between the photosensitive drum and the cleaning member. Thus, the configuration of the present exemplary embodiment is effective in preventing generation of burr of the cleaning member. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all modifications, equivalent structures, and functions. 
     This application claims priority from Japanese Patent Application No. 2010-237466 filed Oct. 22, 2010, which is hereby incorporated by reference herein in its entirety.