CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. provisional patent application Ser. No. 61/125, 512 filed Apr. 25, 2008. This application is also a continuation in part application of U.S. patent application Ser. No. 11/598,964 filed Nov. 14, 2006. 
     
    
     FIELD OF INVENTION 
       [0002]    The present invention relates to electrophotography, particularly methods and apparatus for remanufacturing toner cartridges. 
       BACKGROUND 
       [0003]    Generally, printers embed toner on paper by relying on electrical charges occurring within the printer cartridges. Printer cartridges typically include a toner hopper, a primary charge roller, and a drum. The toner is typically stored in the toner hopper and carries a negative charge. The drum is typically given a charge by a primary charge roller or PCR. The charge of the drum is typically more positive than the charge of the toner, and thus the drum is able to attract the toner. Once the drum is given a charge by the PCR and a print pattern is set, the drum gets coated with toner. The drum that is coated with toner then rolls over a sheet of paper, which is usually given a negative charge by the PCR. The charge of the paper is less negative than the charge of the toner, and thus the paper attracts the toner. The toner is embedded on the paper according to the print pattern. 
         [0004]    Used printer cartridges of fax machines, copiers, inkjet printers, and laser printers are often remanufactured. The drum is usually one of the components that wears out from usage and gets replaced during remanufacturing. In some printer cartridges, such as those manufactured by Hewlett Packard company having model numbers HP 1600, HP 2600, and HP 2605, the drum  2  may be attached to one end of the printer cartridge  4  by a drum flange  6  ( FIG. 1 ). The drum flange  6  may be positioned in between the drum  2  and the cartridge end cap  8 . Referring to  FIG. 2 , a drum portion  10  of the drum flange  6  may be inserted through the drum  2  and an end cap portion  12  of the drum flange  6  may be inserted through the cartridge end cap  8 . The drum flange  6  attaches the drum  2  to the printer cartridge  4  by being connected to both the drum  2  and the cartridge end cap  8 . It can be realized that the drums are attached to the cartridges in a manner that may require breaking the cartridges. 
         [0005]    It is desirable to be able to detach the drums from printer cartridges without having to break parts of the cartridges. This helps preserve the appearance of the cartridges and minimizes remanufacturing steps. Methods and apparatus for efficiently and quickly detaching the drums from the cartridges are desired and are addressed by the present invention. 
       BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE PRESENT INVENTION 
       [0006]    The present invention includes a device for detaching a drum from a cartridge, the device comprising a drive means for driving a drive shaft and a drive shaft attached to the driving means, the drive shaft being configured to drive a drum flange into the drum. 
         [0007]    The present invention also includes a method of removing a drum from a printer cartridge, the drum being attached to the printer cartridge by at least one drum flange, the drum having a hollow interior, the method comprising driving the drum flange towards the interior of the drum. 
         [0008]    The present invention also includes a device for detaching a drum from a printer cartridge, the drum comprising a drum flange that attaches the drum to the printer cartridge, the device comprising: a pressure transmitting device; and a rod operatively connected to the pressure transmitting device, wherein the pressure transmitting device and the rod are configured to apply pressure to the drum flange and cause the drum to be detached from one end of the printer cartridge. 
         [0009]    The above description sets forth, rather broadly, a summary of embodiments of the present invention so that the detailed description that follows may be better understood and contributions of the present invention to the art may be better appreciated. Some of the embodiments of the present invention may not include all of the features or characteristics listed in the above summary. There may be, of course, other features of the invention that will be described below and may form the subject matter of claims. In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of the construction and to the arrangement of the components set forth in the following description or as illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is substantially a perspective view of a waste hopper and drum section of an existing printer cartridge for which the devices and printer remanufacturing methods of the present invention may be applied. 
           [0011]      FIG. 2  is substantially a cross-section view of the drum of the printer cartridge in  FIG. 1  attached to the end cap of the printer cartridge. 
           [0012]      FIG. 3  is substantially a front view of an embodiment of the drum removal device of the present invention. 
           [0013]      FIG. 4  is substantially a front view of another drum removal device embodiment showing cartridges being positioned thereon for drum removal. 
           [0014]      FIG. 5  is substantially a cross-section view of the drum of the printer cartridge in  FIG. 1  with one end being detached from the end cap of the printer cartridge. 
           [0015]      FIG. 6  is substantially a perspective view of an embodiment of the printer cartridge receptacle of the present invention. 
           [0016]      FIG. 7  is substantially a top plan view of the push rods of the drum removal device embodiment of  FIG. 3 . 
           [0017]      FIG. 8  is substantially a front view of the top side of the frame of another drum removal device embodiment. 
           [0018]      FIG. 9  is substantially a perspective view of the drum removal device embodiment of  FIG. 8  with frame doors and bottle jack covers. 
           [0019]      FIG. 10  is substantially a view of another method of printer cartridge drum removal of the present invention. 
           [0020]      FIG. 11  is substantially a front view of another embodiment of the drum removal device of the present invention. 
           [0021]      FIG. 12  is substantially a front view of another embodiment of a drum flange driver of the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part of this application. The drawings show, by way of illustration, specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. 
         [0023]    The order in which the steps are presented below is not limited to any particular order and does not necessarily imply that they have to be performed in the order presented. It will be understood by those of ordinary skill in the art that the order of these steps can be rearranged and performed in any suitable manner. It will further be understood by those of ordinary skill in the art that some steps may be omitted or added and still fall within the spirit of the invention. 
         [0024]    The present invention provides various devices and techniques for removing an organic photoconductor (“OPC”) or drum from a printer cartridge. Referring now to  FIG. 3 , an embodiment of the drum removal device  20  preferably includes a pressure transmitting device  22  attached to a printer cartridge stage  24 . The printer cartridge stage  24  is preferably configured to hold one or multiple printer cartridges that have OPCs that need to be detached from the printer cartridges. The printer cartridge stage  24  preferably includes a plurality of rings  26  and  28  to controllably hold ends of printer cartridges. The number of rings  26  and  28  and the size of the stage  24  may vary depending on the number of printer cartridges that are desired to be serviced. 
         [0025]    The drum removal device embodiment preferably also includes a frame  30  that has four interconnected sides a top side  32 , a bottom side  34 , and a pair of parallel vertical sides  36  and  38 . The pressure transmitting device  22  is preferably attached to the bottom side  34  of the frame  30 . The top side  32  of the frame  30  preferably includes a plurality of push rods  40  and  42 . In the preferred embodiment, the pressure transmitting device  22  is preferably a bottle jack, which is known in the art. The bottle jack may include a cylinder  44  that houses a main lift (not shown). The main lift is preferably connected to the stage  24 . The main lift may be connected to a lever  46 . The bottle jack may also include a release stem  48  to release the pressure to the main lift thereby lowering the main lift and consequently the stage  24 . A plurality of biasing devices  50  and  52 , such as springs, may be attached to the stage  24  to assist the main lift in lowering the stage  24 . 
         [0026]    Referring now to  FIG. 4 , in use, one or plurality of printer cartridges  54  may be positioned vertically on the stage  24 . Each end  56  of the printer cartridge is preferably positioned within the ring  26  or  28 . The push rod  40  or  42  is preferably inserted through the opposite end of the printer cartridge. The bottle jack lever  46  may then be pumped to lift the main lift and the stage  24 . As the stage  24  elevates, the cartridge end  58  that is in contact with the push rod  40  or  42  is subjected to pressure from the push rod  40  or  42  and the pressure transmitting device  22 . The push rod  40  or  42  eventually pushes a drum flange  6  of the OPC  2  ( FIG. 5 ) through the cylindrical interior of the OPC  2  causing the OPC  2  to be detached from the cartridge end cap  8 . 
         [0027]    Referring now to  FIG. 6 , the structures of the stage  24  and the rings  26  and  28  will now be explained in detail. Stage  24  is preferably a substantially flat piece of material, such as stainless steel. The rings  26  and  28  are preferably removably attached to the stage  24 . Each ring  26  or  28  is preferably cylindrical and has open ends. One end of each ring is preferably attached to the stage  24 , and the opposite end preferably includes a notch  29  to accommodate a piece of the printer cartridge, such as its handle, to further secure the printer cartridge to the ring. 
         [0028]    With reference now to  FIG. 7 , the structure and components of the push rods  40  and  42  will now be explained in detail. Each push rod  40  or  42  preferably includes an elongate body  62 . Adjacent and perpendicularly attached to the middle of each elongate body  62  is a rod stop  64 . Each push rod  40  or  42  preferably includes a biasing device  66  positioned around the lower half of each push rod and past each of the rod stop  64 . Referring now to  FIG. 8 , each push rod  40  or  42  may either be in a locked or unlocked position relative to the top side  32  of the frame  30 . When the printer cartridge is being positioned within the frame  30 , the push rod is preferably unlocked. When one end of the printer cartridge is positioned within the ring  26  or  28  and the push rod  40  or  42  is inserted within the other end of the printer cartridge, the push rod  40  or  42  may be pushed down towards the ground until the rod stop  64  reaches the slot  68  of the top side  32  of the frame. The push rod  40  or  42  may be turned to engage the rod stop  64  with the slot  68  thereby locking the push rod  40  or  42 . It can be appreciated that the locking of the push rod  40  or  42  allows the pressure transmitting device  22  to apply pressure to the printer cartridge that is adequate to push the drum flange into the interior of the OPC. 
         [0029]    It is noted that in other embodiments, the pressure transmitting device  22  may be in a form of a mechanical jack, a pneumatic device, a hydraulic device, or a combination of a pneumatic and hydraulic device, all of which are known in the art. Other embodiments, such as shown in  FIG. 9 , may include doors  70   a  and  70   b  that may be positioned around the top portion of the frame and may pivot on one of the vertical sides  36  or  38  of the frame  30 . The doors  70   a  and  70   b  may provide a user some protection against objects that may fly out of the printer cartridge during the OPC removal. The drum removal device may also include a cover  72  surrounding the pressure transmitting device  22 . The cover  22  may define slots that would accommodate the lever  46  and the release stem  48 . 
         [0030]    Referring now to  FIG. 10 , the present invention provides additional methods of detaching a drum  120  from a printer cartridge  122 . The drum may be detached from the printer cartridge by providing pressure that can move or drive a drum flange, which attaches the drum  120  to the printer cartridge  122 , towards the interior of the drum. In one embodiment, the drum flange  6  may be tapped using an appropriately sized center punch  124  and a hammer  126  ( FIG. 10 ). The center punch  124  is preferably appropriately sized to preferably penetrate through the end cap  128  of the printer cartridge. For instance, in HP2600 printers, a center punch with ⅜ inch of diameter can penetrate through the end cap. 
         [0031]    Referring now to  FIG. 11 , another embodiment of a drum removal device is shown that includes a fixture  150 , a base  152 , a pair of driveably shaft mounts  154  and  156  attached to the base  152 , and a cartridge mount  158  also attached to the base  152 . A driveable shaft  160  may be inserted within the shaft mounts  154  and  156 . A connecting rod  164  may be attached to the driveable shaft  160  and the lever  164  so that when the lever  164  is pushed down, the connecting rod  162  causes the driveable shaft  160  to move forward towards the cartridge mount  158  thereby providing a driving action for the driveable shaft  160  to push the drum flange inside the drum. It is noted that the driveable shaft  160  may be driven by other mechanisms. For instance, the driveable shaft  160  may be threaded so that it can be driven using a worm gear or a drill. The driveable shaft  160  may also be provided with an air powered driving mechanism. A cartridge (not shown) may be placed on the fixture  150  by allowing the cartridge mount  158  to receive a portion of one end of the cartridge, such as an end cap, and inserting the driveable shaft  160  to the opposite end of the cartridge where the driveable shaft  160  can contact and push the flange (not shown) towards the inside of the drum (not shown). 
         [0032]    In another embodiment shown in  FIG. 12 , a clamp  132 , such as a straight line action clamp from De-Sta-Co Workholding company of Auburn Hills, Mich. may be used in lieu of the driveable shaft  160 , connecting rod  162 , and lever  164 . The clamp preferably  132  includes a lever  134  and a handle  136 . The lever  134  is preferably connected to a drive shaft  138 . As the lever  314   134  is moved by moving the handle  136 , the lever  134  preferably causes a sliding or driving motion to the drive shaft  138 , which subsequently drives the drum flange out of one of the printer cartridge end caps and towards the inside of the drum. The drive shaft of the clamp  132  may be positioned so that it is in line with the flange and can drive the drum flange into the drum. An additional hold-down clamp (not shown) may be added to the fixture to further prevent printer cartridge movement during the detachment of the drum. 
         [0033]    It can now be realized that the present invention facilitates the removal of the drum with little or no requirement of having to break any portion of the cartridge. This advantage is highly beneficial in the remanufacturing of cartridges, as the appearance of the cartridge is preserved. Additionally, since the removal of the drum by the present invention reduces or avoids having to break any portion of cartridges, the present invention avoids extraneous steps of having to put back broken cartridges. It can also be realized that the present invention provides new techniques for efficiently removing and replacing a toner cartridge drum in a high volume printer cartridge remanufacturing environment. 
         [0034]    Although the description above contains many specifications, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. For example, various mechanisms for driving the drum bearing hub inside the drum may be used. The invention is capable of other embodiments and of being practiced and carried out in various ways. The invention is not limited in its application to the details of the construction and to the arrangement of the components set forth in the above description or as illustrated in the drawings.
A device for detaching a drum from a printer cartridge, the drum comprising a drum flange that attaches the drum to the printer cartridge, the device comprising: a pressure transmitting device; and a rod operatively connected to the pressure transmitting device, wherein the pressure transmitting device and the rod are configured to apply pressure to the drum flange and cause the drum to be detached from the printer cartridge.