Abstract:
A method of reattaching a toner seal to a toner frame having a developer containing portion for containing a developer therein, a developer supplying opening for supplying the developer therethrough from the developer containing portion, in order to seal the developer supplying opening, which method includes (a) the detaching step of detaching the already taken-up toner seal from a take-up spool for taking up the toner seal, (b) the sticking step of sticking the toner seal on the toner frame so as to seal the developer supplying opening, (c) the folding-back step of folding back the toner seal from the end portion of the stuck portion of the toner seal, and (d) the attaching step of attaching the free end portion of the folded-back toner seal to the take-up spool for taking up the toner seal to unseal the developer supplying opening so that the operation of a detecting lever for detecting that a predetermined amount of the toner seal has been taken up to unseal the developer supplying opening may be restricted by the toner seal.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a method of reattaching a toner seal for sealing a developer supplying opening for supplying a developer from a developer containing portion. 
     2. Related Background Art 
     In image forming apparatuses using the electrophotographic image forming process, there has heretofore been adopted a process cartridge system in which an electrophotographic photosensitive member and process means acting on the electrophotographic photosensitive member are integrally made into a cartridge which is detachably mountable on the main body of the image forming apparatus. According to this process cartridge system, the maintenance of the apparatus can be done by a user himself without resorting to a serviceman and therefore, operability could be improved markedly. So, this process cartridge system is widely used in the image forming apparatuses. 
     In such a process cartridge, provision is made of a photosensitive drum, and developing means is used to impart a developer (toner) to a latent image formed on the photosensitive drum. This developing means comprises a developing frame holding a developing roller or the like for feeding the toner to the photosensitive drum, and a toner frame containing the toner therein and connected to the developing frame. Before use, an opening portion provided in the connecting portion between the toner frame and the developing frame is sealed by a seal member. There is conceived an image forming apparatus in which a process cartridge provided with a seal automatic unsealing device for automatically unsealing the seal member sealing the opening portion of the toner frame when the process cartridge is mounted on the main body of the image forming apparatus in case of the first use and the seal automatic take-up device of the process cartridge can be driven. 
     The process cartridge refers to charging means or cleaning means and developing means and an electrophotographic photosensitive drum integrally made into a cartridge which is made detachably mountable to the main body of an image forming apparatus. It also refers to at least one of charging means and cleaning means and developing means and an electrophotographic photosensitive drum integrally made into a cartridge which is made detachably mountable to the main body of the image forming apparatus. It further refers to at least developing means and an electrophotographic photosensitive drum integrally made into a cartridge which is made detachably mountable to the main body of the apparatus. 
     However, in a developer containing portion provided with the aforedescribed toner seal automatic unsealing device, no consideration has been given to easily reattaching the toner seal. 
     So, the present invention solves the above-noted problem. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a method of reattaching a toner seal. 
     It is another object of the present invention to provide a toner seal reattaching method capable of easily reattaching a toner seal. 
     It is another object of the present invention to provide a toner seal reattaching method capable of easily effecting the refilling of a developer containing portion provided with a toner seal automatic unsealing device with a developer. 
     It is another object of the present invention to provide a method of reattaching a toner seal to a toner frame having a developer containing portion for containing a developer therein and a developer supplying opening for supplying the developer therethrough from the developer containing portion, in order to seal the developer supplying opening, comprising; 
     (a) the detaching step of detaching the already taken-up toner seal from a take-up spool for taking up the toner seal; 
     (b) the sticking step of sticking the toner seal on the toner frame so as to seal the developer supplying opening; 
     (c) the folding-back step of folding back the toner seal from the stuck end portion thereof; and 
     (d) the attaching step of attaching the leading end portion of the folded-back toner seal to the take-up spool for taking up the toner seal to unseal the developer supplying opening in the state of restricting by the toner seal the operation of a detecting lever for detecting that a predetermined amount of the toner seal has been taken up to unseal the developer supplying opening. 
     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 
     FIG. 1 is a longitudinal cross-sectional view showing the construction of an image forming apparatus using a toner container according to an embodiment of the present invention. 
     FIG. 2 is a vertical cross-sectional view of a developing device. 
     FIG. 3 is a perspective view showing a state in which a toner seal is attached to the toner container according to the embodiment of the present invention. 
     FIG. 4 is a side view of a toner seal automatic unsealing mechanism. 
     FIG. 5 is a side view of the toner seal automatic unsealing mechanism. 
     FIG. 6 is a perspective view showing a state in which the toner seal has been completely taken up. 
     FIG. 7 is a perspective view showing a state in which the toner seal has been taken away from a take-up spool. 
     FIG. 8 is a perspective view showing a state in which the toner seal has been reattached. 
     FIG. 9 is a perspective view showing a state in which the reattached toner seal has been folded back. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An embodiment in which the present invention is applied to a developing cartridge according to the present invention and a color laser beam printer as an example of an image forming apparatus using the same will hereinafter be specifically described with reference to the drawings. FIG. 1 is a cross-sectional view showing the construction of the image forming apparatus using the developing cartridge according to the present invention, and FIGS. 2 and 3 are a vertical cross-sectional view of the developing cartridge according to the present invention and a perspective view showing the construction of a developer container, respectively. 
     Reference is first had to FIG. 1 to describe the general construction of the image forming apparatus according to the present invention. In FIG. 1, the image forming apparatus transfers toner images formed on the surface of a photosensitive drum  2  which is image forming means comprised of an electrophotographic photosensitive member rotated at a predetermined speed to an intermediate transfer member  3  a predetermined number of times, thereafter collectively transfers the toner images on the intermediate transfer member  3  to a transfer material  5  fed from a cassette  4  which is a feed portion, and transports the transfer material to a fixing device  6 , whereafter the transfer material is delivered to a delivery portion  8  in the upper portion of the main body  1  of the image forming apparatus by delivery rollers  7 . 
     Also, an image forming portion  9  comprising a black developing device  9 B fixed relative to the main body  1  of the image forming apparatus, and rotatable color developing devices  9 Y,  9 M and  9 C of three colors (yellow, magenta and cyan) is provided in proximity to the photosensitive drum  2 , and latent images formed on the photosensitive drum  2  are developed by the image forming portion  9 , and the developed images are multilayer-transferred onto the intermediate transfer member  3 , whereby a color image is formed. 
     The rotatable color developing devices  9 Y,  9 M,  9 C and the stationary black developing device  9 B which are an example of a developing cartridge are discretely detachably mountable to the main body  1  of the apparatus. 
     A process cartridge  10  is constructed integrally with the photosensitive drum  2  and a cleaning container  11  serving also as a holder for the photosensitive drum  2  and for collecting the residuals on the surface of the photosensitive drum  2 . This process cartridge  10  is detachably supported relative to the main body  1  of the apparatus, and is designed to be easily interchangeable in accordance with the service life of the photosensitive drum  2 . 
     The photosensitive drum  2  in the present embodiment is comprised of a cylinder having a diameter of about 62 mm and formed of aluminum, and an organic photoconductor layer applied to the outer side of the cylinder, and is supported for rotation relative to the cleaning container  11  serving also as the holder for the photosensitive drum  2 . Near the outer periphery of the photosensitive drum  2 , there are disposed a cleaning blade  12  which is cleaning means for removing the residuals on the surface of the photosensitive drum  2 , and primary charging means  13  for charging the surface of the photosensitive drum  2 . 
     Also, the photosensitive drum  2  is rotated in the direction indicated by the arrow “a” in FIG. 1 correspondingly to the image forming operation by the driving force of a drive motor, not shown, being transmitted to one end thereof on the back side of the plane of the drawing sheet of FIG.  1 . 
     The primary charging means  13  uses the contact charging method, and the primary charging means  13  which is an electrically conductive roller is brought into contact with the photosensitive drum  2  and a voltage is applied to the primary charging means  13  to thereby uniformly charge the surface of the photosensitive drum  2 . 
     The exposure of the photosensitive drum  2  is effected from a scanner portion  14  disposed in the upper portion of the main body  1  of the apparatus. That is, when an image signal is given to a laser diode, this laser diode applies image light corresponding to the image signal to a polygon mirror  15 . 
     This polygon mirror  15  is rotated at a high speed by a scanner motor, and the surface of the photosensitive drum  2  being rotated at a predetermined speed is selectively exposed to the image light reflected by the polygon mirror  15  through the intermediary of an imaging lens  16  and a reflecting mirror  17 , and as the result, an electrostatic latent image is formed on the surface of the photosensitive drum  2 . 
     The image forming portion  9  for visualizing the electrostatic latent image, as previously described, is comprised of three color developing devices  9 Y,  9 M,  9 C and a black developing device  9 B enabling the color development in yellow, magenta, cyan and black. 
     The black developing device  9 B is a stationary developing device, and a sleeve  9 BS which is a developing rotary member for supplying the photosensitive drum  2  with a black toner which is a developer is disposed at a position opposed to the photosensitive drum  2  with a minute spacing (of the order of 300 μm) relative to the photosensitive drum  2 , and forms a visible image by the black toner correspondingly to the electrostatic latent image on the photosensitive drum  2 . 
     On the other hand, each of the three color developing devices  9 Y,  9 M,  9 C contains therein a toner corresponding to 7,000 pages (A4 size, 5% coverage rate) and is detachably supported by a developing rotary  9   b  rotated about a shaft  9   a . 
     In case of image formation, the respective color developing devices  9 Y,  9 M,  9 C are rotatively moved about the shaft  9   a  while being supported by the developing rotary  9   b , and predetermined one of the color developing devices  9 Y,  9 M,  9 C is stopped at a position opposed to the photosensitive drum  2 , and sleeves  9 YS,  9 MS and  9 CS which are developing rotary members for supplying the photosensitive drum  2  with yellow, magenta and cyan toners which are developers are positioned so as to be opposed to the photosensitive drum  2  with a minute spacing (of the order of 300 μm) relative to the photosensitive drum  2 , whereafter visible images by the color toners are formed correspondingly to the electrostatic latent image on the photosensitive drum  2 . 
     During color image formation, the developing rotary  9   b  is rotated for each one full revolution of the intermediate transfer member  3 , and the developing step is executed in the order of the yellow developing device  9 Y, the magenta developing device  9 M, the cyan developing device  9 C and the black developing device  9 B. 
     In FIG. 1, there is shown a state in which the yellow developing  9 Y is positioned in opposed relationship with the photosensitive drum  2  and is at rest. The yellow developing device  9 Y feeds the developer to a supplying roller  9 YR which is a supplying rotary member for supplying the developer to the surface of the sleeve  9 YS, by a toner feeding mechanism in a developing container for containing the developer therein, and applies a thin layer of toner to the surface of the sleeve  9 YS rotated clockwisely in FIG. 1, by a developing blade  9 YB brought into pressure contact with the outer peripheries of the supplying roller  9 YR and sleeve  9 YS rotated clockwisely in FIG. 1, and induces charges (triboelectrification) in the toner. A developing bias is then applied to the sleeve  9 YS opposed to the photosensitive drum  2  on which the latent image is formed to thereby effect toner development on the photosensitive drum  2  in conformity with the latent image. 
     With regard also to the magenta developing device  9 M and the cyan developing device  9 C, supplying rollers  9 MR,  9 CR which are supplying rotary members and sleeves  9 MS,  9 CS which are developing rotary members and developing blades  9 MB,  9 CB act by a mechanism similar to that described above and the toner developing steps are executed. 
     Also, the respective sleeves  9 YS,  9 MS,  9 CS of the rotatable developing devices  9 Y,  9 M,  9 C are connected to high voltage sources and driving means for respective color development provided in the main body  1  of the apparatus when the respective developing devices  9 Y,  9 M,  9 C are rotatively driven to the developing position, and a voltage is sequentially and selectively applied during each color development and rotative driving is effected. 
     During the color image forming operation, the intermediate transfer member  3  receives the multilayer transfer of the toner images on the photosensitive drum  2  visualized by the respective developing devices  9 Y,  9 M,  9 C,  9 B four times (images of the four colors yellow, magenta, cyan and black) and therefore, it is rotated clockwisely in FIG. 1 in synchronism with the outer peripheral speed of the photosensitive drum  2 , and the intermediate transfer member  3  which has received the multilayer transfer transports the transfer material  5  by nipping the latter between itself and the transfer roller  18  having a voltage applied thereto, whereby the color toner images on the intermediate transfer member  3  are multilayer transferred to the transfer material  5  at a time. 
     In the present embodiment, the intermediate transfer member  3  comprises of a cylinder  3   a  made of aluminum having a diameter of 186 mm of which an outer peripheral is coated with an elastic layer  3   b  such as a medium-resistance sponge and a medium-resistance rubber. The intermediate transfer member  3  is supported to be rotated by a gear (not shown) integrally fixed thereto receiving a drive force. 
     The cleaning means for the photosensitive drum  2  is for removing any toners remaining on the photosensitive drum  2  after the toner images visualized on the photosensitive drum  2  by the developing devices  9 Y,  9 M,  9 C,  9 B are transferred to the intermediate transfer member  3 , and the removed toners are stored in the cleaning container  11 . The amount of the removed toners stored in the cleaning container  11  does not fill the cleaning container  11  earlier than the service life of the photosensitive drum  2  and accordingly, the cleaning container  11  is interchanged simultaneously with the interchange of the photosensitive drum  2  at the end of its service life. 
     The feed portion is for feeding the transfer material  5  to the image forming portion  9 , and is comprised of a cassette  4  containing a plurality of transfer materials  5  therein, and transporting means such as a pickup roller  19 , a feed roller  20 , a double feed preventing retard roller  21 , a feed guide  22 , a transport roller  23  and a registration roller  24 . 
     During image formation, the pickup roller  19  is rotatively driven in conformity with the image forming operation and picks up the transfer materials  5  in the cassette  4 , and the transfer materials are then separated and fed one by one by the cooperative action of the feed roller  20  and the retard roller  21 , and are guided by the feed guide  22  and come to the registration roller  24  via the transport roller  23 . During the image forming operation, the registration roller  24  performs the non-rotating operation of causing the transfer material  5  to come to a halt and stand by and the rotating operation of transporting the transfer material  5  toward the intermediate transfer member  3  at a predetermined sequence, and effects the registration between the image and the transfer material  5  during the transferring step which is the next step. 
     The transfer portion comprises a rockable transfer roller  18 , which in turn comprises a metal shaft and a medium-resistance foamed elastic material wound around the outer periphery thereof, and is movable in a vertical direction in FIG.  1  and is rotatively driven. 
     During the time when toner images of the four colors are being formed on the intermediate transfer member  3 , i.e., during the time when the intermediate transfer member  3  is rotated a plurality of times, the transfer roller  18  is downwardly retracted and spaced apart from the intermediate transfer member  3  so as not to disturb those images, and after the toner images of the four colors are formed on the intermediate transfer member  3 , the transfer roller  18  is urged against the intermediate transfer member  3  with predetermined pressure by a cam member, not shown, with the transfer material  5  interposed therebetween in timed relationship with the transfer of the color images to the transfer material  5 . At this time, a bias is applied to the transfer roller  18  and the toner images formed on the intermediate transfer member  3  are transferred to the transfer material  5 . 
     The intermediate transfer member  3  and the transfer roller  18  are driven independently of each other and therefore, the transfer material  5  nipped between the two is transported leftwardly as viewed in FIG. 1 at a predetermined speed simultaneously with the transferring step being executed, and is sent to the fixing device  6  which is the next step. 
     The fixing device  6  is for fixing the toner images formed by the developing devices  9 Y,  9 M,  9 C,  9 B and transferred onto the transfer material  5  through the intermediate transfer member  3 , and comprises a fixing roller  6   a  for applying heat to the transfer material  5 , and a pressure roller  6   b  for urging the transfer material  5  against the fixing roller, and the rollers  6   a  and  6   b  are hollow rollers having heaters  6   a   1  and  6   b   1 , respectively, therein, and the transfer material  5  is nipped between and transported by the fixing roller  6   a  and the pressure roller  6   b  and has heat and pressure applied thereto, whereby the toner images are fixed on the transfer material  5 . 
     The construction of the toner container using the present invention and the toner seal reattaching step will now be described in detail with reference to FIGS. 2 to  6 . 
     FIG. 3 is a perspective view showing a state in which a toner seal is attached to the toner container according to the present invention. 
     The frame of the developing devices  9 Y,  9 M,  9 C,  9 B, as shown in FIG. 2, has the toner container  25  containing the toners therein and a developing frame  25 A supporting the developing sleeves  9 YS,  9 MS,  9 CS,  9 BS, the developing blades  9 YB,  9 MB,  9 CB,  9 BB and the toner supplying rollers  9 YR,  9 MR,  9 CR,  9 BR, the toner container  25  and the developing frame  25 A being connected together. 
     In FIG. 3, the reference numeral  25  designates a toner container, and the reference character  25   a  denotes an opening in the toner container for supplying the toner therethrough. A toner seal  26  for sealing the opening  25   a  is attached to the opening  25   a  portion of the toner container  25  from the area  26   a  of one end thereof to the area  26   b  of the other end thereof in the lengthwise direction of the opening  25   a  (a direction parallel to the developing sleeve) as by the hot welding method in such a manner as to completely close the opening  25   a  portion of the toner container  25 . After having been attached, the toner seal  26  is folded back at a fold-back portion  26 c, and is put upon the portion thereof attached to the marginal edge of the opening  25   a . The end portion  26   d  of the toner seal is attached to a toner seal take-up spool  27  as by glueing or clasping. The take-up spool  27  is orthogonal to the lengthwise direction of the toner seal  26 , and is rotatably supported by the toner container  25 . A detecting lever  28  for detecting that the toner seal  26  has been completely pulled is in a position  28   a  in which it is detecting that the toner seal  26  is not being pulled. In this state, drive is transmitted to the take-up spool  27  by a driving mechanism, not shown, whereby the take-up spool  27  is rotated and takes up the toner seal  26 . 
     FIG. 6 is a perspective view showing a state in which the toner seal has been completely taken up. 
     As shown in FIG. 2, the toner container  25  has the toner supplying opening  25   a  in a wall portion  25   w . The opening  25   a  is sealed by the toner seal  26  which will be described later. The toner container  25  and a developing frame  25 A have their respective flanges  25   f  and  25 Af ultrasonically welded thereto. Or the flanges  25 Af and  25   f  are made to abut against each other with a sealing packing interposed therebetween and are detachably fastened to each other. 
     The developing sleeve  9 YS, the toner supplying roller  9 YR and the developing blade  9 YB are mounted on the developing frame  25 A. 
     The foregoing description made of the developing device  9 Y also applies to the constructions of the developing devices  9 M and  9 C. 
     The black developing device  9 B is independently mounted and dismounted with respect to the main body of the printer, and differs in shape from the color developing devices  9 Y,  9 M,  9 C, but is similar in construction to the color developing devices  9 Y,  9 M,  9 C with the exception that it has no toner supplying roller, and likewise has a toner seal  26  for sealing the opening  25   a  in the toner container  25 . 
     The construction of an example of a toner seal automatic unsealing mechanism will now be described in detail with reference to FIGS. 3 to  6 . 
     FIG. 4 shows the state before the toner seal  26  is taken up, and FIG. 5 shows the state after the toner seal  26  has been taken up. A side holder  25 E is fixed to the lengthwise end portion of the toner container  25 . Idler gears  31 ,  32 ,  33 , a partly toothless gear  34   a  and a second bevel gear  35  are rotatably supported on a plurality of dowels  25 E 2  provided on the side holder  25 E. An idler gear  31  first meshing with a developing sleeve gear  9   g  is rotatably supported on the side holder  25 E. The developing sleeve gear  9   g  is fixed to one end of the developing sleeve  9 YS coaxially therewith. Subsequently, an idler gear  32  and an,idler gear  33  for reducing the rotative drive from the developing sleeve gear  9   g  to a predetermined number of revolutions successively mesh with each other and are supported. Each of the idler gears  31  and  32  is a two-stage gear and the transmission of the rotation thereof is effected by the pinion (small gear) of the two-stage gear meshing with the gear wheel (large gear) of the partner two-stage gear. Further, the second bevel gear  35  meshing with a first bevel gear  27   a  formed integrally with the take-up spool  27  is in meshing engagement with the idler gear  33  through the partly toothless gear  34   a , and by these gear trains, the driving force inputted from the main body of the printer (the main body of the image forming apparatus) is transmitted to the take-up spool  27 . The second bevel gear  35  has a gear  35   a  integrally therewith. The gear  35   a  is a spur gear and is in meshing engagement with the partly toothless gear  34   a.    
     A toothless clutch  34  is comprised of a partly toothless gear  34   a  having a toothless portion  34   b  lacking some of the teeth thereof (about ⅕ to {fraction (1/10)} of the total teeth), and a spring  36  having one end thereof hooked onto a shaft  34   c  at the tip end of an arm formed integrally with the lengthwisely inner end surface of the partly toothless gear  34   a  to thereby give a rotational force to the partly toothless gear  34   a . The other end of the spring  36  is hooked onto a spring hook  25 E 1  provided on the side holder  25 E. The spring  36  is a tension coil spring. The meshing engagement between the idler gear  33  and the partly toothless gear  34   a  is once interrupted in the toothless portion  34   b  of the partly toothless gear  34   a  when the drive is inputted. At that time, the partly toothless gear  34   a  receives a rotational force from the spring  36  and therefore, the partly toothless gear  34   a  is rotated to a position in which it comes into meshing engagement with the idler gear  33  and accordingly, the two gears  33  and  34   a  again come into meshing engagement with each other. This series of interruption and meshing engagement are repetitively effected for each one full revolution of the partly toothless gear  34   a , and in the state as shown in FIG. 4, before the toner seal  26  is taken up, the meshing engagement between the toothless clutch  34  and the idler gear  33  is continuously kept. Further, a projected portion  34   d  for releasing the meshing engagement between the toothless clutch  34  and the idler gear  33  is formed on the lengthwisely outer end surface of the partly toothless gear  34   a  integrally therewith. 
     Also, detecting means  38  for detecting the take-up of the toner seal  26  and a stopper  39  responsive thereto to release the drive transmission to the take-up spool  27  are provided on the side holder  25 E. The detecting means  38  is held for rotation about an aperture  38   a  fitted on a shaft  25 E 3  provided on the side holder  25 E, and a toner seal detecting lever  28  extending therefrom is designed to abut against the vicinity of the end portion  26   d  of the toner seal  26  (see FIG.  3 ), and this detecting lever  28  is biased toward the vicinity of the end portion  26   d  of the toner seal  26  by a spring  41 . Further, a stopper  39  is formed on the detecting lever  28  integrally therewith, and is operated in operative association with the detecting lever  28  of the detecting means  38  detecting the completion of the take-up of the toner seal  26 , and abuts against the projected portion  34 d of the toothless clutch  34 . The spring  41  has one end thereof engaged with a spring hook  38   e  provided on the tip end portion of an arm  38   d  provided integrally with the detecting means  38  and has the other end thereof engaged with the side holder  25 E. The spring  41  is a tension coil spring. 
     Description will now be made of the specific operation of an automatic unsealing mechanism for the toner seal  26  in the above-described construction. 
     When as shown in FIG. 3, the toner seal  26  is not taken up, the detecting lever  28  of the detecting means  38  abuts against the end portion  26   d  of the folded-back portion of the toner seal  26  and the position thereof is restricted as shown in FIG. 4, and at this time, the stopper  39  is retracted from its abutting position against the projected portion  34   d  of the toothless clutch  34  and the spring  41  is in its pulled state. 
     When in this state, a developing cartridge (which refers to the developing devices  9 Y,  9 S,  9 C) D is mounted on the main body  1  of the image forming apparatus, drive is inputted from a driving gear, not shown, in the main body  1  of the image forming apparatus to a driven input gear (not shown) provided on the opposite end surface of the take-up spool  27 . This driven input gear is in meshing engagement with a developing sleeve gear  9   h  mounted on a flange  9   c  on the side opposite to the lengthwise one end of the developing sleeve  9 YS ( 9 MS,  9 CS,  9 BS) on which the take-up spool  27  is disposed, and rotatively drives the developing sleeve  9 YS ( 9 MS,  9 CS,  9 BS). Thereby, the drive is transmitted from the above-described developing sleeve gear  9   g  to the idler gear  31 , the idler gear  32 , the idler gear  33 , the partly toothless gear  34   a , the gear  35   a , the second bevel gear  35  and the first bevel gear  27   a  by the gear train, and the take-up spool  27  is rotated. 
     Thus, the toner seal  26  is sequentially taken up onto the take-up spool  27  from the state shown in FIG. 3 wherein the opening  25   a  is sealed, and when it is completely taken up by the take-up spool  27 , the opening  25   a  is opened and the toner is supplied to the developing sleeve  9 YS ( 9 MS,  9 CS,  9 BS). 
     Next, when as shown in FIG. 6, the toner seal  26  is completely taken up by the take-up spool  27 , the detecting lever  28  of the detecting means  38  comes to be not restricted by the toner seal  26  and accordingly, is rotatively moved about the aperture  38   a  in the biasing direction of the spring  41  and detects the completion of the take-up of the toner seal  26 . At this time, the stopper  39  is operated in operative association with the detection of the completion of the take-up (the rotative movement), and the tip end thereof is pivotally moved on the locus of the projected portion  34   d  and abuts against the projected portion  34   d  of the toothless clutch  34  and therefore, the drive transmission to the take-up spool  27  is released. When the stopper  39  abuts against the outer periphery of the projected portion  34   d , the front face of the projected portion  34   d  in the direction of movement thereof abuts against the stopper  39  because the stopper  39  is in the locus of the projected portion  34   d  when next the projected portion  34   d  has come round. 
     The interruption of the driving of the toothless clutch  34  will now be described. After the detecting means  38  detects the completion of the take-up of the toner seal  26 , the stopper  39  is moved to a position in which it can abuts against the projected portion  34   d  of the toothless clutch  34 . In this state, the idler gear  33  and the partly toothless gear  34   a  are still in meshing engagement with each other and the projected portion  34   d  has not yet arrived at a position in which it abuts against the stopper  39 , and the drive is not yet interrupted. Thereafter, when the toothless clutch  34  receives a driving force from the idler gear  33  and is rotated thereby, the toothless portion  34   b  of the partly toothless gear  34   a  arrives at a position for meshing with the idler gear  33 , and the meshing engagement between the two gears is interrupted. At this time, the partly toothless gear  34   a  receives a clockwise rotational force from the spring  36  and therefore tries to again rotate to a position in which it meshes with the idler gear  33 , but before that, the projected portion  34   d  abuts against the stopper  39  and therefore, the partly toothless gear  34   a  keeps a state in which the drive transmission is interrupted without the teeth thereof again meshing with the idler gear  33 . When the drive to this partly toothless gear  34   a  is interrupted, the drive to the second bevel gear  35  and the first bevel gear  27   a  is also cut off and therefore, it never happens that the arrive is again applied to the take-up spool  27 . Accordingly, more than necessary rotative drive is not applied to the take-up spool  27  after the take-up of the toner seal  26 , and the scattering of the toner and the production of abnormal sounds or the like by the beating-on caused by the end portion of the toner seal  26  striking against the members on the peripheral surface of the toner container can be prevented and further, it becomes possible to mitigate the load of the drive motor in the main body  1  of the image forming apparatus after the take-up of the toner seal  26 . 
     Referring to FIG. 6, the toner seal  26  is completely taken up by the toner seal take-up spool  27 . Here, the toner seal take-up detecting lever  28  is in a position  28   b  in which it detects that the toner seal  26  is in its taken-up state. In this state, the driving force of a driving mechanism, not shown, is interrupted by the toner seal detecting lever  28  and the driving force is not transmitted to the toner seal take-up spool  27 . 
     (Method of Reattaching the Toner Seal) 
     For the reattachment of the toner seal  26 , the connection between the toner container  25  and the developing frame  25 A shown in FIG. 2 is released. If this connection is the fastening by a faster, for example, a small screw, when the small screw is removed, the toner container  25  and the developing frame  25 A are separated from each other, and the developing frame  25 A is detached while supporting the developing sleeve  9 YS ( 9 MS,  9 CS,  9 BS), the developing blade  9 YB ( 9 MB,  9 CB,  9 BS) and the toner supplying roller  9 YR ( 9 MR,  9 CR). When it is detached, the toner seal  26  is in a state as shown in FIG. 6 wherein it has been taken up onto the take-up shaft  27 . The opening  25   a  in the toner container is opened. 
     If the toner container  25  and the developing frame  25 A are ultrasonically welded together, the toner seal automatically take-up mechanism mounted on the toner container  25  is bodily detached with a side cover and the flange  25   f  portion of the toner container  25  is eliminated, or the developing sleeve, the developing blade and the toner supplying roller are detached from the developing frame  25 A and the flange  25 Af of the developing frame  25 A is eliminated to thereby separate the two from each other. After the reattachment of the toner seal which will be described later, in this case, the toner container  25  and the developing frame  25 A are welded together with a liner of the eliminated thickness interposed between the flanges  25   f  and  25 Af. 
     FIG. 7 is a perspective view showing a state in which the toner seal  26  shown in FIG. 6 has been taken away from the take-up spool  27 . 
     The toner seal  26  which, in FIG. 6, has twined around the toner seal take-up spool  27  is taken away by the toner seal take-up spool  27  being rotated in a direction opposite to the direction in which the toner seal  26  is taken up. In this state, the toner seal take-up detecting lever  28  is in the position  28   b  in which it detects that the toner seal  26  is in its taken-up state. 
     FIG. 8 is a perspective view showing a state in which the toner seal has been reattached. 
     In FIG. 8, the toner seal  26  is welded to the toner container  25  from the area  26   a  to the area  26   b  by the use of the heat welding method or the like, and is in a state in which it completely closes the opening  25   a  in the toner container. In this state, the end portion  26   d  of the toner seal  26  is in a free state. Again here, the toner seal take-up detecting lever  28  is in the position  28   b  in which it detects that the toner seal  26  is in its taken-up state. 
     FIG. 9 is a perspective view showing a state in which the reattached toner seal  26  has been folded back. 
     In FIG. 9, the toner seal  26  welded to the toner container  25  from the area  26   a  to the area  26   b  is folded back in a fold-back portion  26   c.  Again in this state, the end portion  26   d  is in a free state. Also, again here, the toner seal take-up detecting lever  28  is in the position  28   b  in which it detects that the toner seal  26  is in its taken-up state. 
     Lastly, as shown in FIG. 3, the end portion  26   d  of the folded-back toner seal is attached to the toner seal take-up spool  27 . As this time, the toner seal take-up detecting lever  28  is returned from the position  28   b  in which it detects that the toner seal  26  is in its taken-up state to the position  28 a in which it detects that the toner seal  26  is not being pulled. 
     Thereafter, a toner cap closing a toner supplying opening, not shown, formed in the toner container  25  is opened to thereby refill the toner container  25  with the toner, and the toner cap is closed. Next, the toner container  25  and the developing frame  25 A are connected together to thereby obtain the developing devices  9 Y,  9 M,  9 C,  9 B as a developing cartridge. 
     As described above, the reattachment of the toner seal can be accomplished easily, and even in a toner container provided with a toner seal automatic take-up mechanism, the reattachment of the toner seal can be accomplished easily. 
     While the invention has been described with reference to the structure 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.