Abstract:
A remanufacturing method for a process cartridge, wherein the process cartridge is detachably mountable to a main assembly of an electrophotographic image forming apparatus, and the process cartridge including, an electrophotographic photosensitive drum having, at one longitudinal end, a drive receiving portion for receiving came driving force from the main assembly of the electrophotographic image forming apparatus; a drum frame rotatably supporting the electrophotographic photosensitive drum; a developing frame for supporting a developing roller for developing a latent image formed on the electrophotographic photosensitive drum; a developer frame accommodating a developer to be used for a developing operation of the developing roller; a first side cover fixed to 1 longitudinal ends of the drum frame and the developer frame; and a second side cover fixed to the other ends of the drum frame and the developer frame; an image transfer opening formed along a longitudinal direction of the electrophotographic photosensitive drum for permitting transfer of a visualized image provided by the developing roller onto a recording material; a drum supporting shaft having a first shaft portion inserted through a flange portion fixed to the drum frame and the electrophotographic photosensitive drum at the other of the drum frame, and a second shaft portion rejected out of the second side cover through an opening formed therein and extended oppositely from the first shaft portion with the flange portion there between, the method comprising: (a) a first holing step of holing the second side cover around the second shaft portion of the drum supporting shaft to form a first hole; (b) a drum shaft removing step of removing the drum supporting shaft from the drum frame by operation through the first hole formed by the first holing step; (c) a photosensitive drum removing step of removing the electrophotographic photosensitive drum from the drum frame through the transfer opening; (d) a photosensitive drum insertion step of inserting the electrophotographic photosensitive drum into the drum frame through the transfer opening; (e) a drum shaft mounting step of mounting the drum supporting shaft on the drum frame; and (f) a refilling step of filling developer in the developer frame.

Description:
FIELD OF THE INVENTION AND RELATED ART  
         [0001]    The present invention relates to a process cartridge remanufacturing method. Here, a process cartridge means a cartridge in which a minimum of a developing means and an electrophotographic photoconductive member are integrally disposed, and which is removable mountable in the main assembly of an electrophotographic image forming apparatus.  
           [0002]    An electrophotographic image forming apparatus includes an electrophotographic copying machine, an electrophotographic printer(for example, LED printer, laser beam printer, and the like), an electrophotographic facsimile, an electrophotographic word processor, and the like.  
           [0003]    In an electrophotographic image forming apparatus, a process cartridge system has long been employed. According to this system, an electrophotographic photoconductive member, and a single or plurality of processing means, which act on the electrophotographic photoconductive member, are integrated into a form of a cartridge removably mountable in the main assembly of the image forming apparatus. This system enables a user him/her self to maintain the apparatus without relying on a service person, immensely improving the operability of the apparatus. Thus, the process cartridge system has been widely used in the field of an image forming apparatus.  
           [0004]    A process cartridge such as the one described above forms an image on recording medium with the use of developer (toner) contained therein. Therefore, the amount of the developer therein gradually reduces with image formation, eventually to a level below which it fails to form an image satisfactory in quality to the user who purchased the process cartridge. At this point, the process cartridge loses its commercial value.  
           [0005]    Thus, it has long been desired to realize a simple method for remanufacturing a process cartridge so that a process cartridge which has lost its commercial value due to the depletion of the developer therein can be marketed again.  
         SUMMARY OF THE INVENTION  
         [0006]    The primary object of the present invention is to provide a simple method for remanufacturing a process cartridge.  
           [0007]    Another object of the present invention is to provide a method for remanufacturing a process cartridge, the commercial value of which has been lost due to the consumption of the developer therein to a level below which the process cartridge fails to forms an image satisfactory in quality to a user who has purchased the process cartridge.  
           [0008]    According to an aspect of the present invention, there is provided a remanufacturing method for a process cartridge, wherein the process cartridge is detachably mountable to a main assembly of an electrophotographic image forming apparatus, and the process cartridge including, an electrophotographic photosensitive drum having, at one longitudinal end, a drive receiving portion for receiving came driving force from the main assembly of the electrophotographic image forming apparatus; a drum frame rotatably supporting the electrophotographic photosensitive drum; a developing frame for supporting a developing roller for developing a latent image formed on the electrophotographic photosensitive drum; a developer frame accommodating a developer to be used for a developing operation of the developing roller; a first side cover fixed to 1 longitudinal ends of the drum frame and the developer frame; and a second side cover fixed to the other ends of the drum frame and the developer frame; an image transfer opening formed along a longitudinal direction of the electrophotographic photosensitive drum for permitting transfer of a visualized image provided by the developing roller onto a recording material; a drum supporting shaft having a first shaft portion inserted through a flange portion fixed to the drum frame and the electrophotographic photosensitive drum at the other of the drum frame, and a second shaft portion rejected out of the second side cover through an opening formed therein and extended oppositely from the first shaft portion with the flange portion there between, the method comprising: (a) a first holing step of holing the second side cover around the second shaft portion of the drum supporting shaft to form a first hole; (b) a drum shaft removing step of removing the drum supporting shaft from the drum frame by operation through the first hole formed by the first holing step; (c) a photosensitive drum removing step of removing the electrophotographic photosensitive drum from the drum frame through the transfer opening; (d) a photosensitive drum insertion step of inserting the electrophotographic photosensitive drum into the drum frame through the transfer opening; (e) a drum shaft mounting step of mounting the drum supporting shaft on the drum frame; and (f) a refilling step of filling developer in the developer frame.  
           [0009]    These and other objects, features, and advantages of the present invention will become more apparent upon consideration of the following description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    [0010]FIG. 1 is a longitudinal sectional view of an electrophotographic image forming apparatus.  
         [0011]    [0011]FIG. 2 is a longitudinal sectional view of a process cartridge.  
         [0012]    [0012]FIG. 3 is an exploded perspective view of a process cartridge.  
         [0013]    [0013]FIG. 4 is a perspective view illustrating a forming method for a sealing member for a process cartridge.  
         [0014]    [0014]FIG. 5 is a perspective view illustrating a forming method for a sealing member for a process cartridge.  
         [0015]    [0015]FIG. 6 is a rear view of a process cartridge with a side cover omitted.  
         [0016]    [0016]FIG. 7 is a front view of a process cartridge with a side cover omitted.  
         [0017]    [0017]FIG. 8 is a front view of a toner seal for a toner accommodating container.  
         [0018]    [0018]FIG. 9 is a sectional view illustrating a layer structure of a toner seal member.  
         [0019]    [0019]FIG. 10 is a sectional front view of a toner accommodating container before welding.  
         [0020]    [0020]FIG. 11 is a sectional front view of a toner accommodating container after welding.  
         [0021]    [0021]FIG. 12 is a perspective view illustrating a connecting method of a side cover for the process cartridge.  
         [0022]    [0022]FIG. 13 is a perspective view around the side cover, illustrating a remanufacturing method of a process cartridge.  
         [0023]    [0023]FIG. 14 is a front view illustrating a remanufacturing method of a process cartridge.  
         [0024]    [0024]FIG. 15 is a bottom plan view of the process cartridge, illustrating a showing of a remanufacturing method.  
         [0025]    [0025]FIG. 16 is a sectional front view of a cleaning frame and a developing device, illustrating a remanufacturing method for a process cartridge.  
         [0026]    [0026]FIG. 17 is a perspective view around a side cover, illustrating a remanufacturing method of a process cartridge.  
         [0027]    [0027]FIG. 18 is a perspective view, illustrating toner refilling operation in a remanufacturing method of a process cartridge.  
         [0028]    [0028]FIG. 19 is a bottom plan view of a process cartridge, illustrating a remanufacturing method of a process cartridge. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0029]    Hereinafter, the preferred embodiments of the present invention will be described with reference to FIGS.  1 - 9 . In the following embodiments, the lengthwise direction means a direction which is perpendicular to the recording medium conveyance direction, and is parallel to the surface of the recording medium being conveyed.  
         [0030]    (Embodiment 1)  
         [0031]    (Description of Process Cartridge and Image Forming Apparatus Main Assembly)  
         [0032]    [0032]FIG. 1 shows the vertical section of a typical electrophotographic image forming apparatus, perpendicular to the lengthwise direction, and FIG. 2 shows the vertical section of a typical process cartridge, perpendicular to the lengthwise direction.  
         [0033]    The process cartridge P in this embodiment is structured as shown in FIG. 2. In other words, the process cartridge P comprises: a drum holding frame, which hereinafter will be called cleaning frame  13 , in which a charge roller  12  as a charging means, and a cleaning blade  14  as a cleaning means, are disposed around an electrophotographic photoconductive drum  11 ; a developing means holding frame, as a developing apparatus D, which supports a development roller  18  and development blade  26 ; a toner storage container in which stirring members  34 ,  35 , and  36  for stirring the toner are provided, and to which a toner storage lid  31  is welded.  
         [0034]    A drum protection shutter  19  for protecting the photoconductive drum  11  is supported by the drum holding frame  13 . These frame and shutter are integrated into the form of a cartridge P, which can be mount or dismount, into or from, the image forming apparatus main assembly C, without subjecting the processing means to an undue amount of force, by grasping a handle  10  provided on the top surface of the toner storage lid  31 .  
         [0035]    The shutter  9  takes a closed position at which it completely covers the transfer opening  13   n , or an open position at which it fully exposes the transfer opening n. More specifically, as the cartridge P is moved out of the apparatus main assembly C, it moves from the open position to the closed position, preventing the photoconductive drum  11  from being physically damaged, or from being exposed to external light, and as the cartridge P is mounted into the apparatus main assembly C, it moves from the closed position to the opening position, exposing the transfer opening  13   n , allowing the photoconductive drum  11  to directly oppose a transfer roller  5 . The transfer opening  13   n  is narrow and long, and its dimension in terms of the lengthwise direction of the photoconductive drum  11  exceeds the image formation range in terms of the lengthwise direction of the photoconductive drum  11 . The dimension of the transfer opening  13   n  in terms of the direction perpendicular to the lengthwise direction of the photoconductive drum  11  is greater than the diameter of the photoconductive drum  11 . The transfer opening  13   n  is located between the drum holding frame  13  and developing means holding frame  17 . In terms of the lengthwise direction, the position of one of the edges of the transfer opening  13   n  coincides with the position of the inward surface of the bearing cover portion  13   h  extending downward from the cleaning frame  13 , whereas the position of the other edge coincides with the position of the inward surface of the bearing cover portion  30   m  extending downward from the bottom cover  29  attached to the developer container  30 . The bearing cover portions  13   h  and  30   m  are connected to each other at a joint  44 , forming an arcuate portion, the center of which virtually coincides with the axial line of the photoconductive drum  11 . The peripheral surface of the photoconductive drum  11  is exposed through this transfer opening  13   n.    
         [0036]    As described above, the positions of the short edges, that is, the edges at the lengthwise ends, of the transfer opening  13   n  coincide with those of the inward surfaces of the bearing cover portions  13   h  and  30   m.    
         [0037]    The cartridge P is mounted in an image forming apparatus such as the one shown in FIG. 1, to be used for image formation.  
         [0038]    The photoconductive drum  11  is charged by the charge roller  12 , and selectively exposed by an exposing apparatus  8 , in accordance with the image formation data. As a result, an electrostatic latent image is formed. The exposing operation by the exposing apparatus  8  is carried out in synchronism with the conveyance of the sheet S by a registration roller pair  3 .  
         [0039]    Meanwhile, the toner in the toner storage unit  16  is conveyed to the development means holding frame  17 , in which it is borne in a thin layer on the peripheral surface of the development roller  18  by the development blade  26 . Then, development bias is applied to the development roller  18  so that the toner is supplied to the latent image on the peripheral surface of the photoconductive drum  11 . As a result, a toner image is formed on the peripheral surface of the photoconductive drum  11 . This toner image is transferred onto the aforementioned sheet S, which is being conveyed through the transfer station after having been conveyed thereto by the conveying rollers  7 , by the application of bias voltage to the transfer roller  5 . Then, the sheet S is conveyed to a fixing apparatus  4 , in which the toner image is fixed to the sheet S. Then, the sheet S is discharged into a delivery portion  2  on top of the apparatus main assembly, by sheet discharge rollers  1 . Meanwhile, the residual toner, that is, the developer remaining on the peripheral surface of the photoconductive drum  11 , is removed by the cleaning blade  14 , and is collected into the drum holding frame  13 .  
         [0040]    (Structure of Process Cartridge Frame)  
         [0041]    Next, the developing apparatus and its adjacencies will be described further in detail.  
         [0042]    [0042]FIGS. 2 and 3 shows the structure of the cartridge P in this embodiment. The developing apparatus D of the cartridge P places the toner from the toner storage unit  16  onto the peripheral surface of the development roller  18 , and then, supplies the toner on the peripheral surface of the development roller  18  to the peripheral surface of the photoconductive drum  11 , in accordance with the latent image on the peripheral surface of the photoconductive drum  11 , by applying development bias to the development roller  18 .  
         [0043]    The development roller  18  is cylindrical, and is formed of a metallic material such as aluminum or stainless steel. It contains a magnetic roller  18   a.    
         [0044]    [0044]FIG. 3 is an exploded perspective view of the cartridge P, for showing the components and structure of the cartridge P. The positional relationships between the toner storage unit  16  and side covers  19  and  20  become accurately fixed as the positioning joggles  30   a  protruding from the outward surfaces of the side walls, in terms of the lengthwise direction, of the developer holding frame  30 , into the center holes of the bosses  19   c  and  20   c  of the end covers  19  and  20 , respectively. The cleaning frame  13  rotationally supports the drum  11 , with the interposition of a bearing  41  and a drum shaft  40  located at the lengthwise ends, one for one. The positioning joggle  19   b  and  20   b  are fitted into the center holes of the positioning bosses  13   b , one for one. As a result, the cleaning frame  13  becomes fixed to the end covers  19  and  20  as is the toner storage unit  16 .  
         [0045]    In other words, the frame  13  and unit  16  are held together by the end covers  19  and  20 . The shaft  40  is provided with a flange portion  40   a , a first shaft portion  40   b , and a second shaft portion  40   c . The flange portion  40   a  is the portion by which the shaft  40  is attached to the frame  13 , and the a first shaft portion  40   b  is the portion to be inserted into the center hole of the flange  11   a  of the drum  11 . The second shaft portion  40   c  perpendicularly protrudes from the outward surface of the flange portion  40   a  (therefore, in the direction opposite to the direction in which the first shaft portion  40   b  protrudes), long enough to project outward through the hole  19   a  of the end cover  19 . The aforementioned flange  11   a  is guided by a U-shaped groove  13   g  (contoured by a dotted line in FIG. 3, and contoured by a solid line in FIG. 17) in the inward surface of the frame  13 , when the drum  11  is mounted in the frame  13 . Further, the flange  11   a  has a guide portion  11   a   1  for temporarily keeping the drum  11  accurately positioned relative to the frame  13  until the attachment of the shaft  40 . This guide portion  11   a   1  is cylindrical, and is smaller in diameter than the portion of the flange  11   a , from the outward surface of which it perpendicularly projects. Its axial line coincides with that of the drum  11 .  
         [0046]    Referring to FIGS. 2 and 3, the developing means holding frame  17  of the developing apparatus D supports developing members such as the development roller  18 , development blade  12 , and the like. It is connected to the frame  13 , with the pins inserted in the holes  13   a  (FIG. 6) of the frame  13  and the holes  17   a  of the developing means holding frame  17 , being enabled to pivot about the axial line of the holes  17   d  ( 13   a ). Here, referring to FIG. 6, which shows one of the lengthwise ends of the cartridge P, with the end cover  20  removed, a tension coil spring  22  is stretched between the frame  13  and frame  17 , being attached to the spring anchoring portions  13   c  and  17   f  projecting from the frames  13  and  17 , respectively.  
         [0047]    Next, referring to FIG. 3, and FIG. 7 which shows the lengthwise end of the cartridge opposite to the end shown in FIG. 6, a compression coil spring  27  is fitted in a groove  19   e  of the cover  19 , being compressed so that it presses the development roller bearing  17   e , which is secured to the lengthwise end of the frame  17 , rotationally supporting one of the lengthwise ends of the development roller  18 . With the presence of the force from the spring  22 , a pair of spacer rings  18   b , which are greater in radius by an amount equivalent to the development gap (approximately 300 μm) than the photoconductive drum  11  and are concentrically fitted around the lengthwise end portions of the development roller  18 , are kept pressed upon the peripheral surface of the photoconductive drum  11 , outside the image formation range. With the provision of this structural arrangement, a gap is provided between the developing means holding frame  17  and developer holding frame  13 .  
         [0048]    In this embodiment, the gap between the developing apparatus D and developer holding frame  30  is sealed with a sealing member in the formed of follows, which is made by folding and pasting a jointing sheet  21  attached to the developer holding frame  30  with the inter position of a jointing plate  23 . The jointing sheet  21  in this embodiment is no more than 1 mm in thickness. However, the jointing sheet thickness may be more than 1 mm, provided that the substance selected as the material for the jointing sheet  21  is such that even if it is made into a jointing sheet thicker than 1 mm, it does not prevent the bellows-like jointing member, into which the jointing sheet is fold, from remaining flexible.  
         [0049]    Referring to FIG. 12, the outwardly edge  13   d  of the cleaning frame  13 , the outward edge  16   a  of the toner storage unit  16 , and inward edge  19   i  of the cover  19 , are structured so that as the combination of the drum holding frame  13  and toner storage unit  16  is joined with the cover  19 , a groove (unshown) is formed, into which melted resin is flowed through the gate  19   h  of the cover  19 . As melted resin is flowed into this groove, the frame  13 , unit  16 , and cover  19  are solidly secure to each other. The, the cover  20  is also joined with the combination of the frame  13  and unit  16 , in the same manner as is the cover  19 , completing the cartridge P.  
         [0050]    The charge roller  12  comprises a metallic core  12   c , and a cylindrical rubber layer (FIG. 3) fitted around the metallic core  12   c . The electrical resistance of the rubber layer is in the mid range. Referring to FIG. 17, the frame  13  is provided with a guide-way  13   i , which extends in the lengthwise direction of the frame  13  in parallel to the axial line of the photoconductive drum  11 , astride the axial line of the photoconductive drum  11 , in terms of the direction perpendicular to the lengthwise direction of the photoconductive drum  11 . In this guide-way  13   i , a charge roller bearing  12   a  is slidably fitted. In this bearing  12   a , the metallic core  12   c  of the charge roller  12  is rotationally fitted. At the rear end of the cartridge P, a compression coil spring  12   b  is disposed between the guide-way  13   i  and bearing  12   a . The spring  12   b  is fitted around a projection of the charge roller bearing  12   a , with the anchoring portion of the spring  12   b  tightly fitted around the base portion of the projection, facilitating the process cartridge assembly. With this structural arrangement, the charge roller  12  is kept pressed upon the drum  11 , by the pressure applied to the charge roller  12  by the resiliency of the spring  12   b  through the bearing  12   b . Incidentally, the charge roller  12  is rotated by the rotation of the photoconductive drum  11 .  
         [0051]    (Method for Forming Pouch-like Sealing Member)  
         [0052]    Next, referring to FIGS. 4 and 5, a method for forming the pouch-like sealing member from the jointing sheet  21  is roughly described. Referring to FIG. 4, the jointing sheet  21  is provided with holes  21   a  and  21   b , the sizes of which are approximately the same as, or greater than, those of the holes  23   b  and  17   b  of the jointing plate  23  and developing means holding frame  17 , respectively. The jointing sheet  21  is attached to the edges of the holes  23   b  and  17   b  of the jointing plate  23  and developing means holding frame  17 , by the edge portions  21   c  and  21   e  of the holes.  
         [0053]    In this embodiment, the jointing sheet  21  is attached to the developing means holding frame  17  and jointing plate  23  by a thermal welding method, such as a thermal sealing method or an impulse sealing method. However, ultrasonic welding, adhesive, adhesive tape, or the like methods, may be used.  
         [0054]    After being attached to the developing means holding frame  17  and jointing plate  23 , the jointing sheet  21  is folded in the direction indicated by an arrow mark, as shown in FIG. 5, so that the holes  21   a  and  21   b  squarely face each other (holes  23   b  and  17   b  squarely face each other). Then, the two sections of the jointing sheet  21  created by the folding are attached to each other, by the entirety of the edge portion  21   d , creating a bellows-like (pouch-like) member. The means for attaching the above described two sections of the jointing sheet  21  may also be a thermal welding method such as a heat sealing method or an impulse sealing method, a ultrasonic welding, adhesive, adhesive tape, or the like.  
         [0055]    Next, the jointing plate  23  is attached to the developer container  30 , leaving partially unwelded or unpasted to provide a gap through which a toner seal  24  can be passed. In this embodiment, the portion  23   a  is welded or pasted to the surface  30   h  (FIG. 10) of the developer container  30  provided with a hole  32  as a toner delivery hole, except for the area across which the toner seal  24  is kept pressed by a toner sealing member  25  (FIG. 3).  
         [0056]    The provision of the above described structural arrangement, in other words, the placement of the a pouch-like bellows formed of the jointing sheet  21  between the mutually facing surfaces of the container  30  and frame  17  minimizes the resistance which occurs as the distance between the mutually facing surfaces of the frame  30  and frame  17  varies. Further, the placement of the jointing sheet  21  between the jointing plate  23  and developing means holding frame  17  makes it possible to attach the jointing plate  23  in a manner to cover the toner seal  24 . With the provision of this arrangement, the toner sealing member  25  can be placed in the gap through which the toner seal  24  is passed, preventing toner leak (FIG. 6).  
         [0057]    The provision of the jointing plate  23  makes simpler the configuration of the welding table necessary for welding the jointing sheet  21  to the mutually facing surfaces of the frame  17  and jointing plate  23 , compared to that necessary in the absence of the jointing plate  23 , that is, when the jointing sheet  21  has to be directly pasted to the frame  30 .  
         [0058]    Further, the provision of the jointing plate  23  makes it possible to assemble the developing means holding frame  17 , jointing plate  23 , and jointing sheet  21  into a unit which can be easily attached to the container  30 . The frame  17  and unit  16  jointed together into a development unit.  
         [0059]    (Mounting or Dismounting of Process Cartridge into or out of Apparatus Main Assembly)  
         [0060]    [0060]FIG. 1 is a sectional view of an image forming apparatus, in which the cartridge P is ready for image formation. In order to dismount the cartridge P in the state shown in FIG. 2, a lever (unshown) located on the front wall of the apparatus main assembly C is to be rotated. As the lever is rotated, an arm  28  is rotated in the direction indicated by an arrow mark (I). As a result, the left side of the cartridge P, with reference to the drawing, is raised by a part (unshown) of the arm  28 . As the left side of the cartridge P is raised, the cartridge P rotates, while being raised, about the guide portions  15   b  rested on the guide rails  111  of the apparatus main assembly C, until the guide portions  15   a , with which only the back side of the cartridge P is provided, aligns with the guide rails  110  of the apparatus main assembly C. In this state, the cartridge P is to be pulled toward the front side of the apparatus main assembly C, in the direction perpendicular to the plane of the FIG. 1. As the cartridge P is pulled, the guide portions  15   a  transfers onto the guide rails  110 , and the cartridge P becomes disengaged from the arm  28 . Then, the cartridge P can be pulled straight out of the apparatus main assembly C.  
         [0061]    The procedure for mounting the cartridge P into the apparatus main assembly C is reverse to the above described dismounting procedure. In other words, the cartridge is to be inserted into the apparatus main assembly C, with the guide portion  15   a  and fulcrum  15   b  aligned with the rails  110  and  111 , in the direction perpendicular to the plane of the FIG. 1. As the cartridge is inserted inward of the apparatus main assembly C, the top left portion of the cartridge P is caught by the arm  28  before the guide portion  15   a  becomes disengaged from the rail  110 . Then, as the cartridge P is pushed further into the apparatus main assembly C, the guide portion  15   a  disengages from the rail  110 . Then, a lock (unshown) of the arm  28  is to be disengaged, and the aforementioned lever (unshown) on the front side of the apparatus main assembly C is to be rotated to rotate the arm  28  in the direction opposite to the direction indicated by the arrow mark (I). The rotation of the arm  28  is assisted by the weight of the cartridge P itself.  
         [0062]    As the cartridge P approaches the position at which the cartridge can form an image, the second shaft portion  40   c  of the drum shaft  40  (FIG. 3) protruding outward of the cover  19 , through the aforementioned hole  19   a  of the cover  19 , shown in FIG. 3, fits into the drum shaft positioning recess (unshown) of the apparatus main assembly C, being therefore accurately positioned (drum bearing  41  on the cover  20  side protrudes outward through the hole  20   a  of the cover  20 ). As a result, the cartridge P is accurately positioned relative to the apparatus main assembly C, and therefore, the photoconductive drum  11  is accurately positioned relative to the apparatus main assembly C, because the axial lines of the photoconductive drum  11 , drum bearing  41 , and drum shaft  40  coincide.  
         [0063]    The side wall of the cover  19 , which surrounds the second shaft portion  40   c , makes contact with the inward surface of the portion of apparatus main assembly C with the recess (unshown) in which the shaft portion  40   c  fits. As a result, the position of the cartridge P relative to the apparatus main assembly C in terms of the lengthwise direction is accurately fixed. With the provision of the above described structural arrangement, even a process cartridge (P), which is heavy because of a large amount of toner contained in the developer container  30 , can be smoothly mounted into, or dismounted from, the apparatus main assembly C. Incidentally, the cartridge P is also provided with a handle  19   g  (FIG. 12), in addition to the handle  10  on the top surface. The handle  19   g  is attached to the second cover  19 , being on the front side in terms of the direction in which the cartridge P is mounted or dismounted. The provision of the additional handle  19   g  makes it easier to carry the cartridge P, and also to handle the cartridge P at the beginning of the mounting of the cartridge P or the end of the dismounting of the cartridge P.  
         [0064]    The flange  11   b  of the drum  11 , on the driven side, comprises a journal portion  11   b   1 , which is rotationally supported by the bearing  41 , and a driving force receiving portion  11   b   2 , which projects from the journal portion  11   b   1 . The driving force receiving portion  11   b   2  is in the form of a triangular pillar which is twisted about its axial line, and has a cross section in the form of an equilateral triangle. It is driven by the driving shaft on the apparatus main assembly C side, being fitted into the twisted triangular hole (unshown) of the driving shaft.  
         [0065]    (Description of Toner Storage Unit)  
         [0066]    Next, referring to FIGS. 8, 9,  10 , and  11 , the unit  16  will be described. The unit  16  comprises the container  30 , toner storage lid  31 , and stirring members  34 ,  35 , and  36 . Referring to FIG. 8, the container  30  is provided with the developer delivery hole  32  through which the toner is sent out to the developing means holding frame  17 . The hole  32  is covered with the seal  24 , which is thermally welded to the unit  16 , along the surrounding edge of the hole  32  (FIG. 8). A referential code  50  stands for the welded portion (hatched portion).  
         [0067]    The toner seal  24  in this embodiment has a laminar structure, having:  
         [0068]    a 12 μm thick polyester layer (strength providing layer:  24   i  in FIG. 9),  
         [0069]    a 7 μm thick aluminum foil layer (laser beam blocking layer:  24   j  in FIG. 9),  
         [0070]    a 50 μm thick polyester layer (tear guiding layer:  24   k  in FIG. 9), and  
         [0071]    a 50 μm thick sealant layer (adhesive layer:  24   l  (el) in FIG. 9), listing from the top layer.  
         [0072]    Tear lines  24   e  of the seal  24 , along which the seal  24  is torn open, have been subjected to a laser-cut process for creating gaps in the tear guiding layer, along the tear lines  24   e . FIG. 9 is a sectional view of the seal  24 . The seal  24  has a gap  24   h  created by a laser. The provision of the aluminum foil layer  24   j  which blocks a laser beam prevents the top polyester layer, or the strength providing layer  24   i , from being damaged by the laser beam, assuring satisfactory sealing performance. The provision of the aluminum foil layer also causes the stress to concentrate to the gap  24   h  when the seal  24  is pulled to be opened, ensuring that the seal  24  is torn along the tear lines  24   e.    
         [0073]    Referring to FIG. 10, within the container  30 , the stirring members  34 ,  35 , and  36  are provided, which send the toner to the developing means holding frame  17  through the toner delivery hole  32 , while stirring the toner. The stirring members  34 ,  35 , and  36  comprise: shaft  34   c ,  35   c , and  36   c ; stirring blades  34   a ,  35   a , and  36   a ; and blade holders  34   b ,  35   b , and  36   b , by which the stirring blades  34   a ,  35   a , and  36   a , are held to the shafts  34   c ,  35   c , and  36   c , respectively. In this embodiment, the blade  34   a  is formed of 50 μm thick PPS sheet, and blades  35   a  and  36   a  are formed of approximately 100 μm thick PPS sheet. The stirring members  34 ,  35 , and  36  all rotate in the same direction (clockwise in FIG. 2). The stirring member  34 , that is, the stirring member nearest to the developing means holding frame  17  rotates at approximately 20 rpm, and the other two stirring members  35  and  36  rotate at approximately 5 rpm.  
         [0074]    The bottom wall of the container  30  is shaped so that its cross section looks as if it is made by connecting three semicircles:  30   c ,  30   d , and  30   e , the centers of which coincide with the axial lines of the shafts  34   c ,  35   c , and  36   c , respectively. The distances from the axial lines of the shafts  34   c ,  35   c , and  36   c  to the tips of the blades  34   a ,  35   a , and  36   a , when the blades are straight, are made greater than the radii of the semicircular portions  30   c ,  30   d , and  30   e , respectively, making it possible for the blades  34   a ,  35   a , and  36   a  to stir the toner while scraping the bottom wall of the container  30 . Therefore, even after the remaining amount of the toner becomes small due to toner delivery, the blades can scrape the toner away from the bottom wall, and send the toner to the developing means holding frame  17 , reducing the amount of the unusable toner, or the toner which fails to be delivered and remains in the developer holding container  30 . In this embodiment, the distances the blades  34   a ,  35   a , and  36   a  hypothetically invade into the semicircular portions  30   c ,  30   d , and  30   e , respectively, of the bottom wall are 2-4 mm.  
         [0075]    Within the container  30 , a bridge-like rib  30   b  is provided, which extends from the internal surface  30   i  of the wall  30   h  to which the aforementioned jointing plate  23  is attached in a manner to cover the hole  32 , to the rear wall  30   k , in terms of the cartridge mounting direction, of the container  30 . The bottom edge of the rib  30   b  is contoured so that it does not interfere with the installation of the stirring member  34  into the container  30 , being slanted across the portion  30   j  near the edge of the hole  32 , and being arcuate across the portion  30   m  next to the rear wall  30   k.    
         [0076]    The lid  31  is provided with isolation ribs  31   a  and  31   b , which extend in the lengthwise direction of the cartridge. In terms of the direction perpendicular to the lengthwise direction of the cartridge, the positions of the isolation ribs  31   a  and  31   b  virtually coincide with the position of the joint  30   f  between the semicircular portions  30   c  and  30   d , and the position of the joint  30   g  between the semicircular portions  30   d  and  30   e , of the bottom wall of the container  30 . In order for the ribs  31   a  and  31   b  not to interfere with the rib  30   b  within the developer container  30 , the center portions  31   c  of the rib  31   a  and  31   b  have been cut out (FIG. 3). After the installation of the stirring members  34 ,  35 , and  36  into the container  30 , the lid  31  and container  30  are welded to each other by ultrasonic welding or vibration welding, completing the toner storage unit  16 . The gaps  37  and  38  left between the ribs  31   a  and  31   b  and the protruding joints  30   f  and  30   g  are the gaps necessary for sending out the toner. In this embodiment, the gaps are approximately 10 mm-30 mm wide.  
         [0077]    After assembling the unit  16  as described above, the container  30  is filled with the toner through the toner inlet  30     1    (el), and is sealed with a toner cap  39 , completing the unit  16 .  
         [0078]    The inlet  30     1    (el) is provided as a filling opening at one of the lengthwise ends of the container  30 .  
         [0079]    (Embodiment 1 of Process Cartridge Remanufacturing Method in Accordance with Present Invention)  
         [0080]    Next, a method for overhauling the cartridge P in this embodiment will be described.  
         [0081]    As shown in FIG. 13, the process cartridge P is fixed by a chuck of a milling machine. A peripheral portion of a drum supporting shaft  40  (hatched portion Q) projected out of the side cover  19  is cut off using an end mill V. In this embodiment, the milling cutter is used for the cutting, but another cutting tool such as an ultrasonic cutter, a heated blade, or another rotating cutter (a auger cutter having a hollow cylindrical end, for example). The portion cut out of the side cover  19  (the inside portion of the hatched portion Q) is pulled off the drum supporting shaft  40 , by which the hole  19   r  is formed. In the similar manner, the portion of the side cover  19  corresponding to the toner filling opening  301  provided in the toner accommodating container  30  (hatched portion R) is cut off, by which a hole  19   t  is formed.  
         [0082]    Thereafter, a tool is inserted through the hole  19   r  shown in FIG. 14 to a thread the small screws  61  fixing the flange portion  40   a  of the drum supporting shaft  40  to the cleaning frame  13 . Then, the drum supporting shaft  40  is pulled out of the cleaning frame  13  through the hole  19   r . FIG. 15 is a bottom view of the process cartridge P. In this FIGURE., projected portions  13   c ,  13   f  extended integrally from the cleaning frame  13  adjacent the longitudinal end portion of the image transfer opening  13   n  covers neighborhoods of the longitudinal ends of the photosensitive drum  11 . Each of the surfaces of the projected portions  13   c ,  13   f  opposed to the photosensitive drum  11  are provided with a magnet (unshown) for collecting the toner, a small amount of which may scatter at the longitudinal end portions of the cleaning blade  14 .  
         [0083]    A guide portion  11   a   1  of a flange  11   a  provided at one end of the photosensitive drum  11  is covered by bearing cover portions  13   h ,  30   m  which is a frame defining a short side of the transfer opening  13   n . In this embodiment, the projected portions  13   e ,  13   f  are cut off by a cutter, an ultrasonic cutter or another cutting tool to remove a part (indicated by hatching) of the frame covering the guide portion  11   a   1 . Then, a flange  11   a  side of the photosensitive drum  11  is raised to incline the process cartridge, and the photosensitive drum  11  is pulled out through the transfer opening  13   n  in the direction indicated by an arrow Y. In this manner, the photosensitive drum  11  can be taken out of the process cartridge P. FIG. 16 illustrates the process cartridge P from which the photosensitive drum  11  has been removed.  
         [0084]    Thereafter, as desired, the charging roller  12  and/or the cleaning blade  14  is removed.  
         [0085]    In FIG. 16, the charging roller bearing  12   a  is sandwiched in the lower end of the guideway  13   i  in the slightly narrowed space which opens to the outside, and is stopped against the spring force of the compression coil spring  12   b . When the charging roller  12  is pulled toward the transfer opening  13   n , the charging roller bearing  12   a  expands the guideway  13   i  against the elastic force, and the assembled charging roller bearing  12   a  and compression coil spring  12   b  are dismounted. The charging roller  12  is first removed through the transfer opening  13   n , and then the small screws  62  securing the cleaning blade  14  to the cleaning frame  13  are unthreaded, and thereafter, the cleaning blade  14  is removed. At this time, the small screws  62  are unthreaded by a ratchet driver or a similar electric driver having a cross-type tip end. If the amount of the toner removed from the surface of the photosensitive drum  11  and contained in the cleaning frame  13  is large, the toner is removed. This is done by vacuum suction using a suction nozzle (unshown) inside into the removed toner container portion through the transfer opening  13   n . Simultaneously, the air may be supplied. After toner is removed from the cleaning frame  13 , a new cleaning blade or the same cleaning blade  14  that has been removed, if it is reusable, is mounted by small screws  62  to the cleaning frame  13 . In addition, a new charging roller or the removed charging roller  12  is mounted.  
         [0086]    The description will be made as to insertion of the photosensitive drum  11 . If the photosensitive drum  11  is reusable, the removed one is remounted. When the photosensitive drum  11  is inserted into the cleaning frame  13 , the process cartridge P is placed on the Table such that transfer opening  13   n  faces up, and is inclined such that flange portion  11   a  side takes a slightly upper position. Then, the flange portion  11   b  is inserted through the transfer opening  13   n  into a hole of the bearing  41 . Thereafter, the flange portion  11   a  side is placed in the cleaning frame  13 . The drum supporting shaft  40  is inserted through the hole  19   r  formed in the earlier step in the side cover  19 . Then, the shaft portion  40   b  is engaged into the center hole of the flange  11   a . The drum supporting shaft  40  is securedly fixed to the cleaning frame  13  by small screws  61 . As shown in FIG. 17, a cylindrical positioning member  43  for positioning in the longitudinal direction is mounted to the shaft portion  40   c  of the drum supporting shaft  40  by press-fitting or adhesive material. An end surface  43   a  of the positioning member  43  takes substantially the same longitudinal position as the cut portion of the side cover  19 , and when the process cartridge P is mounted to the main assembly C of the apparatus, it functions to determine the position of the process cartridge P in the longitudinal direction.  
         [0087]    Here, the positioning member  43  is cylindrical, and the inner diameter of the hollow portion is substantially equal to the outer diameter of the shaft portion  40   c . What is important is that position of the end surface  43   a  in the longitudinal direction relates the position of the process cartridge P in the longitudinal direction when it is mounted to the main assembly C of the apparatus, and therefore, the configuration and the mounting method of the positioning member  43  may be modified in various ways.  
         [0088]    Subsequently, the toner is filled. The toner cap  39  mounted to the toner filling opening  301  of the toner accommodating container  30  is removed through the hole  19   t  formed in the side cover  19 , and as shown in FIG. 18, the filling port  301  is made to take a higher position, and then a funnel  29  is inserted into the filling port  301 . Then, a desired amount of the toner T is filled into the filling port  301 . After the toner is filled, the removed toner cap  39  is mounted if it is reusable. If the toner cap  39  is damaged, for example, a new toner cap is used to seal the filling port  301 . After the toner is filled into the toner accommodating container  30 , the toner deposited around the filling port  301  is removed.  
         [0089]    In this manner, the process cartridge P is remanufactured.  
         [0090]    In this embodiment, in the photosensitive drum  11  removing step, the hole is formed in the side cover  19 ; the drum supporting shaft  40  is removed; the projected portions  13   e ,  13   f  and the part of the portion defining the short side of the transfer opening  13   n  is cut off; and then the photosensitive drum  11  is removed. However, the order of the steps is not limited to this. For example, in an alternative order, the projected portions  13   e ,  13   f  and the frame defining the short side of the transfer opening  13   n , that is, a part of the bearing cover portions  13   h ,  30   m  is cut off, and then the side cover  19  is holed, and thereafter, the drum supporting shaft  40  is removed, whereafter the photosensitive drum  11  is taken out. In this embodiment, the positioning member  43  is mounted after the drum supporting shaft  40  is mounted. However, the drum supporting shaft  40  may be mounted to the cleaning frame  13  after the positioning member  43  is mounted to the drum supporting shaft  40 . When the toner filling opening is provided at the side cover  20  side, the side cover  20  is holed so that hole  19   t  is formed in the side cover  20 , and the toner is filled.  
         [0091]    As regards the refill of the toner, it would be considered that hole is formed in a part of the toner accommodating container  30  or the toner accommodation cap  31  constituting the toner accommodating unit  16  not in the side cover  19 , and the toner is filled through the whole, and then the hole is sealed by a tape or a plate material (sealing member). This, however, would result in falling of the chips of resin material into the toner accommodating container  30  the side cover  19  is holed. According to this embodiment, the hole is formed in the side cover  19 , and the toner cap  39  is removed, and thereafter, the toner is filled through the filling port  301 . Therefore, the problem does not arise.  
         [0092]    (Embodiment 2)  
         [0093]    Embodiment 2 all the present invention will be described. Since this embodiment is different from Embodiment 1 in the step of removing the photosensitive drum  11  only, the description will be made only as to the points different from Embodiment 1.  
         [0094]    In the photosensitive drum  11  removing step in Embodiment 1, the hole is formed in the side cover  19 , and the drum supporting shaft  40  is removed, and then the projected portions  13   e ,  13   f  and the part of the frame defining the short side of a transfer opening is cut off, and thereafter, the photosensitive drum  11  is removed. In Embodiment    2   , a part of the photosensitive drum  11  is cut off in place of cutting off a part of each of the bearing cover portions  13   h ,  30   m  which is the frame defining the short side of the transfer opening, and then the photosensitive drum  11  is removed.  
         [0095]    This will be described in detail. In FIG. 19, a thin cutter or the like is inserted through a gap SL between the flange  11   a  of the photosensitive drum  11  and the short side of the transfer opening  13   n , and the guide portion  11   a   1  of the flange  11   a  is cut off. Then, similarly to Embodiment 1, the projected portions  13   e ,  13   f  are cut out. The side cover  19  is partly cut off around the drum supporting shaft  40  to form a hole  19   r , and the drum supporting shaft  40  is taken out. Thereafter, the process cartridge P is remanufactured.  
         [0096]    If the photosensitive drum  11  is not reusable due to wearing or the like, the central portion of the drum, rather than the guide portion  11   a   1 , is cut to divide it into two parts, which are then taken out of the cleaning frame  13 .  
         [0097]    As described in the foregoing with respect to Embodiments 1 and 2, the hole is formed in the side cover  19 , and the drum supporting shaft  40  is removed, and then the photosensitive drum  11  is taken out through the transfer opening  13   n , thus disassembling the process cartridge P; t photosensitive drum  11  is inserted through the transfer opening  13   n , and the drum supporting shaft  40  is mounted, and then the toner is filled, by which the process cartridge P is remanufactured.  
         [0098]    In the process cartridge P described in the embodiments, the positioning in the longitudinal direction is carried out by the portion of the side cover  19  around the drum supporting shaft  40 , and therefore, the positioning member  43  is mounted. When the other portion of the process cartridge is used for the positioning, it is not necessary to mount the positioning member  43 .  
         [0099]    Similarly, if the process cartridge P does not have the projected portions  13   e ,  13   f , the step of cutting the projected portions  13   e ,  13   f  off is omitted; if the process cartridge P does not have the guide portion  11   a   1  of the flange  11   a , it is not necessary to cut off the part of the frame defining the short side of the transfer opening  13   n  or the part of the photosensitive drum  11 .  
         [0100]    Those processes in the process cartridge remanufacturing methods in accordance with the present invention may be changed in order as necessary.  
         [0101]    The above described embodiments of the present invention include a process cartridge remanufacturing method which involves simultaneously a substantial number of process cartridges with an expired service life, as well as a process cartridge remanufacturing method which involves a single process cartridge with an expired service life. In the case of the former, a substantial number of expired cartridges are recovered, and disassembled. Then, the components removed from the disassembled cartridges are sorted into groups of the identical components. Then, as large as possible a number of cartridges are reassembled from the groups of sorted recyclable components, and some new replacement components for the nonrecyclable old components. In the case of the latter, the expired cartridges are remanufactured one by one. In other words, each time an expired cartridge is recovered, it is disassembled, and reassembled using the same old components removed therefrom, some new replacement components for the nonrecyclable old components, or some old recyclable components removed from the other recovered cartridges.  
         [0102]    The present invention includes any of the following cases:  
         [0103]    (1) each expired cartridge is overhauled using only the components therein;  
         [0104]    (2) each expired cartridge is overhauled using, in principle, the components therein, with the exception of the new replacement components, or the recyclable old components from the other expired cartridge, which replace the original components nonrecyclable due to service life expiration, damages, malfunctions, or the like;  
         [0105]    (3) a plurality of expired cartridges are overhauled together; the components removed from the plurality of expired cartridges are sorted into groups of the identical components, and as large as possible a number of cartridges are reassembled using only the components from the groups of the original components; and  
         [0106]    (4) a plurality of expired cartridges are overhauled together; the components removed from the plurality of expired cartridges are sorted into groups of the identical components, and as large as possible a number of cartridges are reassembled using, in principle, the components from the groups of the original components, except for a certain number of new replacement components which replace the original components nonrecyclable due to service life expiration, damages, malfunctions, or the like.  
         [0107]    The aforementioned components means the structural components disclosed in the claim portion of this specification, that is, the components which make up the above described portions of the cartridge. It also includes the smallest components or units, into which the cartridge can be disassembled.  
         [0108]    As described above, the present invention is a realization of a simple method for remanufacturing a process cartridge.  
         [0109]    While the invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth, and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.