Patent Publication Number: US-6907205-B2

Title: Coupling arrangement including drum and flange

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority to U.S. provisional application No. 60/384,107, to Himes et al., filed May 31, 2002, the disclosure of which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a coupling arrangement including an optical photo-conductive (OPC) drum and a flange (e.g., a driving flange and/or a driven flange) in an electro-photographic (EP) machine, and more particularly to a coupling arrangement including a protrusion of the OPC drum disposed in a receiving portion of the flange. 
     2. Discussion of the Related Art 
     In a known electro-photographic (EP) machine, such as a photocopier, a laser printer, and a facsimile, a known process cartridge is removably mounted to a known main assembly. 
     The main assembly of the EP machine generally includes, among other components, a housing, a control panel disposed within the housing for controlling an image forming process, an electronic control system that is operated by the control panel, a motor that is controlled by the control system, a gear train that is driven by the motor, and electrical contacts for delivering power to the process cartridge that is inserted into and retained within grooves or channels formed in opposing side walls of the housing. The main assembly generally also includes an optical projection system and a central processor that controls a sequence and a timing of the optical projection system during a known image forming operation. 
     The process cartridge generally includes, among other components, an optical photo-conductive (OPC) drum, and a driving gear for driving one or more components of the process cartridge, such as a charging device, a developing device, and a cleaning device. 
     During the known image forming operation, the OPC drum undergoes a charging portion and a discharging portion of a charging/discharging cycle to ultimately create a developer image (e.g., a toner image) on a recording material (e.g., a sheet of paper, a transparent sheet, etc.). Briefly, during the charging portion of the charging/discharging cycle, the charging device uniformly charges an exterior surface of the OPC drum. The optical projection system projects image containing information in the form of a laser light to selectively discharge a portion of the exterior surface of the OPC drum, thereby forming a latent image on the OPC drum. The developing device applies a developer (e.g., a toner) to the partially charged exterior surface of the OPC drum. The developer is electro-statically attracted to the charged areas of the OPC drum, thereby forming the developer image. The developer image is then transferred from the exterior surface of the OPC drum to the recording material. 
     In the known process cartridge, the exterior surface of the OPC drum is coated with an electrically resistive coating to improve a quality of the image produced during the image forming process. Examples of known electrically resistive coatings include hard anodization with aluminum oxide (Al 2 O 3 ) and oxidized surfaces. Generally, during a coating process, the OPC drum is submerged in the electrically resistive coating, such that an interior surface of the OPC drum, as well as the exterior surface, is coated with the electrically resistive coating. 
     It is known that the coated interior surface of the OPC drum must be sufficiently grounded for the OPC drum to undergo the required discharging portion of the charging/discharging cycle. In a known grounding or earthing arrangement, a grounding plate is disposed beneath the driving gear and within an interior portion of the OPC drum. The grounding plate includes a plurality of first radially extending projections that contact the interior surface of the OPC drum. To satisfactorily ground the OPC drum with the coated interior surface, the electrically resistive coating must be removed from a contact area of the interior surface through a separate and additional process (i.e., a process after the coating of the OPC drum), such that the first projections can achieve electrical connection with the interior surface of the OPC drum. An example of a known process for removing the electrically resistive coating includes a laser scribing operation. The grounding plate also includes a plurality of second radially extending projections that contact an electrically conductive shaft extending through the driving gear. 
     Thus, during assembly of the known process cartridge, the grounding plate is aligned with and inserted into the OPC drum, such that the first projections of the grounding plate achieve electrical connection with the contact areas of the OPC drum. The driving gear is then secured to the OPC drum by known securing means, thereby preventing relative movement and rotation, and preventing disassembly, among the OPC drum, the driving gear, and the grounding plate. Examples of securing means include an adhesive and a press fit arrangement. The electrically conductive shaft extends through the driving gear, and achieves electrical connection with the second projections of the grounding plate. By these arrangements, the OPC drum is sufficiently grounded through the grounding plate and the electrically conductive shaft. 
     However, the known OPC drum assembly suffers from a number of disadvantages. For example, during curing of the adhesive, care must be taken to maintain precise alignment and to prevent relative rotation and movement of the driving gear and the grounding plate relative to the OPC drum. Failure to maintain precise alignment may result in failure to achieve sufficient grounding of the OPC drum. The requirement to maintain precise alignment acts as an impediment to an automatic assembly of the OPC drum assembly. Further, the inadvertent use of an undesirably large volume of adhesive may result in adhesive flow into undesired portions of the known OPC drum assembly, and may degrade performance of the OPC drum assembly. The use of an undesirably small volume of adhesive may result in poor bond formation and inadequate bond strength between the OPC drum and the driving gear, and may reduce a useful life of the OPC drum assembly. Further, the press fit arrangement requires a relatively high degree of mechanical precision of each of the OPC drum and the driving gear (e.g., tolerances related to cylindricity of the driving gear and the OPC drum) to achieve satisfactory securing of the OPC drum and the driving gear. Such disadvantages increase a manufacturing time and/or a manufacturing cost of the known OPC drum assembly. 
     SUMMARY OF THE INVENTION 
     The present invention provides a coupling arrangement having an optical photo-conductive drum including drum exterior and interior surfaces surrounding and extending along a longitudinal axis, the drum exterior surface facing away from the longitudinal axis, and the drum interior surface facing toward the longitudinal axis and including first and second open ends and at least one protrusion disposed apart from the first and second open ends. A flange includes a flange interior surface disposed in the first open end, a flange exterior surface disposed outside of the first open end, a flange side surface connecting the flange interior and exterior surfaces, and at least one receiving portion. The at least one protrusion is disposed in the at least one receiving portion. 
     The present invention further provides an optical photo-conductive drum. A drum exterior surface surrounds and extends along a longitudinal axis, the drum exterior surface facing away from the longitudinal axis. A drum interior surface surrounds and extends along the longitudinal axis, the drum interior surface facing toward the longitudinal axis and including first and second open ends. At least one protrusion is disposed apart from the first and second open ends. 
     The present invention further provides a process cartridge adapted to be removably mounted on an electro-photographic machine including a coupling arrangement. The coupling arrangement has an optical photo-conductive drum including drum exterior and interior surfaces surrounding and extending along a longitudinal axis, the drum exterior surface facing away from the longitudinal axis, and the drum interior surface facing toward the longitudinal axis and including first and second open ends and at least one protrusion disposed apart from the first and second open ends. A flange includes a flange interior surface disposed in the first open end, a flange exterior surface disposed outside of the first open end, a flange side surface connecting the flange interior and exterior surfaces, and at least one receiving portion. The at least one protrusion is disposed in the at least one receiving portion. 
     The present invention further provides an electro-photographic machine, including a main portion and a coupling arrangement removably mounted on the main portion. The coupling arrangement has an optical photo-conductive drum including drum exterior and interior surfaces surrounding and extending along a longitudinal axis, the drum exterior surface facing away from the longitudinal axis, and the drum interior surface facing toward the longitudinal axis and including first and second open ends and at least one protrusion disposed apart from the first and second open ends. A flange includes a flange interior surface disposed in the first open end, a flange exterior surface disposed outside of the first open end, a flange side surface connecting the flange interior and exterior surfaces, and at least one receiving portion. The at least one protrusion is disposed in the at least one receiving portion. 
     The present invention further provides a coupling arrangement having an optical photo-conductive drum including drum exterior and interior surfaces surrounding and extending along a longitudinal axis, the drum exterior surface facing away from the longitudinal axis, and the drum interior surface facing toward the longitudinal axis and including first and second open ends and a first structure for securing disposed apart from the first and second open ends. A flange includes a flange interior surface disposed in the first open end, a flange exterior surface disposed outside of the first open end, a flange side surface connecting the flange interior and exterior surfaces, and a second structure for securing. The first structure for securing is disposed in the second structure for securing. 
     The present invention further provides a method of assembling a coupling arrangement including an optical photo-conductive drum having a drum exterior surface and a drum interior surface including first and second open ends. The method includes inserting a flange including a receiving portion in the first open end, and forming a protrusion on the optical photo-conductive drum, the protrusion being received in the receiving portion. 
     The present invention still further provides a coupling arrangement produced by a method of assembling a coupling arrangement including an optical photo-conductive drum having a drum exterior surface and a drum interior surface including first and second open ends. The method includes inserting a flange including a receiving portion in the first open end, and forming a protrusion on the photo-conductive drum, the protrusion being received in the receiving portion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete appreciation of the present invention, and many of the attendant advantages thereof, will be readily ascertained and/or obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: 
         FIG. 1  shows an exploded isometric view of a coupling arrangement including an optical photo-conductive (OPC) drum and a flange according to the present invention. 
         FIG. 2  shows an elevation view of the flange of FIG.  1 . 
         FIG. 3  shows an elevation view of another embodiment of a flange according to the present invention. 
         FIG. 4  shows an elevation partial cross-sectional view of the coupling arrangement of FIG.  1 . 
         FIG. 5  shows a cross-sectional view of a photocopier including a process cartridge with the coupling arrangement of FIG.  1 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Examples of preferred embodiments of the present invention will now be described with reference to the drawings, wherein like reference numbers throughout the several views identify like and/or similar elements. 
     The figures show an example of a coupling arrangement that can include an optical photo-conductive (OPC) drum and a flange (e.g., a driving flange and/or a driven flange) of a process cartridge removably mounted to a main assembly of an electro-photographic (EP) machine. 
     In certain preferred embodiments of the present invention, the coupling arrangement has an OPC drum that includes drum exterior and interior surfaces surrounding and extending along a longitudinal axis, the drum exterior surface facing away from the longitudinal axis, and the drum interior surface facing toward the longitudinal axis and including first and second open ends and at least one protrusion disposed apart from the first and second open ends. The flange includes a flange interior surface disposed in the first open end, a flange exterior surface disposed outside of the first open end, a flange side surface connecting the flange interior and exterior surfaces, and at least one receiving portion. The at least one protrusion is disposed in the at least one receiving portion. By this arrangement, the OPC drum can be secured with and prevented from rotation and/or movement relative to the flange. The coupling arrangement can be secured without the use of additional securing means, such as an adhesive and/or a press fit arrangement. Further, the coupling arrangement can withstand an application of a predetermined axial and/or torsional force, such that material properties of the OPC drum and/or the flange can determine a strength of the coupling arrangement. 
     Specifically, as shown in the figures, a coupling arrangement  100  according to the present invention can include, among other components, an optical photo-conductive (OPC) drum  10 , a flange (e.g., a driving flange and/or a driven flange)  20 , a grounding shaft  30 , and a grounding plate  40 , examples of which are discussed below. 
     During an image forming process, an electro-static latent image and a subsequent developer image (i.e., a toner image) can be formed on the OPC drum  10  for transfer to a recording material (e.g., a sheet of paper, a transparent sheet, etc.). Thus, although the drawings show certain preferred embodiments of the OPC drum  10 , it is to be understood that the OPC drum  10  can be of any type on which an electro-static latent image and/or a developer image can be formed. 
     As shown in the figures, the OPC drum  10  can include a drum exterior surface  11  and a drum interior surface  12 , both of which can extend about along, and can be about coaxial with, a longitudinal axis  13 . The drum exterior surface  11  can face away from the longitudinal axis  13 , and the drum interior surface  12  can face toward the longitudinal axis  13 . By this arrangement, the drum exterior and interior surfaces  11  and  12  can define the OPC drum  10 , such that the OPC drum  10  can be about cylindrical in shape. The drum interior surface  12  can include first and second open ends  14  and  15 , respectively. 
     At least one of the drum exterior surface  11  and the drum interior surface  12  can include an electrically resistive coating, such as a hard anodization with aluminum oxide (Al 2 O 3 ) and/or oxidized surfaces. The electrically resistive coating can be formed on the drum exterior surface  11  to improve a quality of the image formed thereon in the image forming process, and the electrically resistive coating can be formed on the drum interior surface  12  as a consequence of the formation of the coating on the drum exterior surface  11  (e.g., by submerging the OPC drum  10  into the coating during a known coating process). The electrically resistive coating can be sufficiently electrically resistive so as to impede a discharging portion of a charging/discharging cycle of the OPC drum  10 , such that removal of a portion of the electrically resistive coating from at least one contact area  16  of the drum interior surface  12  can improve electrical connection therewith, and can achieve the image formed in the image forming process. The electrically resistive coating can be removed from the at least one contact area  16  ( FIG. 4 ) of the drum interior surface  12  by at least one known resistive coating removal method, such that the OPC drum  10  can be grounded. In a preferred embodiment of the invention, the electrically resistive coating can be removed from two contact areas  16  of the drum interior surface  12 , and can be removed by a laser scribing operation. The OPC drum  10  can be of any material that can be used in the formation of the latent image and/or in the formation of the developer image, such as aluminum. 
     The OPC drum  10  can include at least one protrusion  17  ( FIG. 4 ) to be disposed in a receiving portion of the flange  20 , and the at least one protrusion  17  can be disposed apart from the first and second open ends  14  and  15  of the OPC drum  10 . By this arrangement, the OPC drum  10  can be secured with and can be prevented from rotation and/or movement relative to the flange  20 . The coupling arrangement  100  can be secured without the use of additional securing means, such as an adhesive and/or a press fit arrangement between the OPC drum  10  and the flange  20 . Further, the coupling arrangement  100  can withstand an application of a predetermined axial and/or torsional force, such that material properties of the OPC drum  10  and/or the flange  20  can determine a strength of the coupling arrangement  100 . Specifically, because portions of the OPC drum  10  and the flange  20  can be used to connect the OPC drum  10  and the flange  20 , the weaker of the respective portions of the OPC drum  11  and the flange  20  defines the strength of the coupling arrangement  100 . 
     In a preferred embodiment of the invention, the at least one protrusion  17  can have a shape that can be a consequence of methods of assembling the coupling arrangement  100 . Preferably, the at least one protrusion  17  can have a shape that includes one or more of an arc, an ellipse, a circle, and a polygon (such as a triangle, a rectangle, a square, a diamond, a pentagon, a hexagon, a heptagon, an octagon, etc.), as well as combinations of these and other shapes. Thus, although the drawings show certain preferred shapes of the at least one protrusion  17 , it is to be understood that the at least one protrusion  17  can be of any shape, so long as the at least one protrusion  17  can be disposed in a receiving portion of the flange  20 . 
     In a preferred embodiment of the invention, the at least one protrusion  17  can include a plurality of protrusions  17  that are spaced at a variety of locations on the drum interior surface  12 , and more preferably can include two (2) protrusions  17  that are about equally spaced about the drum interior surface  12 . Further, the plurality of protrusions  17  can correspond to a plurality of receiving portions of the flange  20 . Thus, in a preferred embodiment of the invention, the OPC drum  10  can include two (2) protrusions  17  that are about equally spaced about the drum interior surface  12  and that correspond to two (2) receiving portions on the flange  20 . 
     Further details of the at least one protrusion  17  are discussed below with reference to methods of assembling the coupling arrangement  100 . 
     As shown in the drawings, the flange  20  (e.g., a driving flange that can be used to drive at least one component of at least one of a process cartridge that includes the coupling arrangement  100  and the EP machine and/or a driven flange) can include a flange interior surface  21  that can be disposed within the first open end  14  of the OPC drum  10 , and can include a flange exterior surface  22  that can be disposed opposite to the flange interior surface  21  and outside of the first open end  14 . The flange interior and exterior surfaces  21  and  22  can be about parallel to one another and can be about perpendicular to a longitudinal axis  23  of the flange  20 , and the longitudinal axis  23  can be about perpendicular to the longitudinal axis  13  of the OPC drum  10  when the flange  20  is inserted into the first open end  14  of the OPC drum  10 . 
     The flange interior surface  21  can include one or more grounding alignment posts (not shown) corresponding to one or more alignment voids in the grounding plate  40  to aid in assembly of the coupling arrangement  100 , and more particularly to aid in the insertion of the grounding plate  40  with the flange  20  into the OPC drum  10 . The grounding alignment posts of the flange  20  and the corresponding alignment voids of the grounding plate  40  can be of a known type having an “x” or cross-shaped cross-section. The flange interior surface  21  can include a plurality of grounding alignment posts, and can include at least four (4) grounding alignment posts that correspond to at least four (4) alignment voids in the grounding plate  40 . 
     A flange side surface  24  can extend between the flange interior and exterior surfaces  21  and  22  and can be about perpendicular to the longitudinal axis  23 . The flange side surface  24  can include a first profile  25  disposed adjacent to the flange exterior surface  22  and can include a second profile  26  disposed adjacent to the flange interior surface  21 , the first and second profiles  25  and  26  extending along the longitudinal axis  23 . The first profile  25  can include one or more geared driving teeth for driving at least one component of at least one of the process cartridge and the EP machine. The second profile  26  can be disposed within the OPC drum  10 , and can be sized to achieve an interference fit with the drum interior surface  12  of the OPC drum  10 . The first profile  25  can have a maximum diameter that is equal to or greater than a maximum diameter of the second profile  26 , such that the flange side surface  24  can have a stepped profile. By this arrangement, when the flange interior surface  21  is inserted into the OPC drum  10 , a step of the flange side surface  24  can abut an end of the first open end  14  of the OPC drum  10 , such that complete insertion of the flange  20  into the OPC drum  10  can be achieved. 
     The flange  20  can include a grounding shaft opening  27  that extends between the flange interior surface  21  and the flange exterior surface  22  to communicate an interior and an exterior of the OPC drum  10 . The grounding shaft opening  27  can be sized to achieve an interference fit with one or more surfaces of the grounding shaft  30 . The grounding shaft opening  27  can be about concentric with, and can be about perpendicular to, the longitudinal axis  23  of the flange  20 . The flange  20  can be of any material that can be used to drive at least one component of at least one of the process cartridge and the EP machine during the image forming process, such as an engineering plastic resin that can include at least one of a thermoplastic and/or a thermoset. Examples of such plastics can include polyacetals, nylons, and/or polyesters. 
     The flange  20  can include at least one receiving portion  28  to receive the at least one protrusion  17  of the OPC drum  10 . By this arrangement, the OPC drum  10  can be secured with and can be prevented from rotation and/or movement relative to the flange  20 . The coupling arrangement  100  can be secured without the use of additional securing means, such as an adhesive and/or a press fit arrangement between the OPC drum  10  and the flange  20 . Further, the coupling arrangement  100  can withstand an application of a predetermined axial and/or torsional force, such that material properties of the OPC drum  10  and/or the flange  20  can determine a strength of the coupling arrangement  100 . Specifically, because portions of the OPC drum  10  and the flange  20  can be used to connect the OPC drum  10  and the flange  20 , a weaker of the respective portions of the OPC drum  10  and the flange  20  can define the strength of the coupling arrangement  100 . 
     In a preferred embodiment of the invention, the at least one receiving portion  28  can have a shape that corresponds to the shape of the at least one protrusion  17  as a consequence of methods of assembling the coupling arrangement  100 . Preferably, the at least one receiving portion  28  can have a shape that includes one or more of an arc, an ellipse, a circle, and an equivalent arcuate shape, and a polygon (such as a triangle, a rectangle, a square, a diamond, a pentagon, a hexagon, a heptagon, an octagon, etc.), as well as combinations of these and other shapes. Thus, although the drawings show certain preferred shapes of the at least one receiving portion  28 , it is to be understood that the at least one receiving portion  28  can be of any shape, so long as the at least one receiving portion  28  can receive the at least one protrusion  17  of the OPC drum  10 . Further, the at least one receiving portion  28  can be formed during an initial manufacturing process of the flange  20  (e.g., during an injection molding of the flange  20 ), and/or can be formed after an initial manufacturing process of the flange  20  (e.g., by machining after the flange  20  is substantially otherwise completed). 
     The at least one receiving portion  28  can be disposed on the flange side surface  24  of the flange  20 . In a preferred embodiment of the invention, the at least one receiving portion  28  can be disposed on the second profile  26  of the flange side surface  24  that can be disposed in the first open end  14  of the OPC drum  10 . Although the drawings show certain preferred locations of the at least one receiving portion  28 , it is to be understood that the at least one receiving portion  28  can be disposed at any position along the second profile  26 , including at a position that can be adjacent to an edge of the first profile  25  of the flange side surface  24 , and/or at a position that can be disposed apart from an edge of the first profile  25 . 
     In a preferred embodiment of the invention, the at least one receiving portion  28  can include a plurality of receiving portions  28  that are spaced at a variety of locations on second profile  26 , and more preferably can include two (2) receiving portions  28  that are about equally spaced on the second profile  26 . Further, the plurality of receiving portions  28  can correspond to the plurality of protrusions  17  of the OPC drum  10 . Thus, in a preferred embodiment of the invention, the flange  20  can include two (2) receiving portions  28  that are about equally spaced on the second profile  26  and that correspond to two (2) protrusions  17  of the OPC drum  10 . Further, one or more of the at least one protrusion  17  (e.g., either or both of the protrusions  17 ) can be disposed in the at least one receiving portions  28  (e.g., either of both of the receiving portions  28 ) such that the protrusion(s)  17  cannot be easily removed from the receiving portion(s)  28  after insertion thereinto. 
     In a preferred embodiment of the invention, the at least one receiving portion  28  can be in the form of at least one blind void (i.e., a void closed at one end). 
     Further details of the at least one receiving portion  28  are discussed below with reference to methods of assembling the coupling arrangement  100 . 
     The flange  20  can optionally include an adhesive channel (not shown) that can be used in conjunction with the receiving portion  28  to secure with the OPC drum  10 . The adhesive channel can be disposed on the flange side surface  24  of the flange  20 , and can be disposed on the second profile  26  of the flange side surface  24  that can be disposed in the first open end  14  of the OPC drum  10 . Further, it is to be understood that the adhesive channel can be disposed at any position along the second profile  26 , including at a position that can be adjacent to an edge of the first profile  25  of the flange side surface  24 , and/or at a position that can be disposed apart from an edge of the first profile  25 . 
     As shown in the drawings, the grounding shaft  30  can include a first end  31  and can include a second end  35  extending about along an axis  39 . At least one of the first end  31  and the second end  35  can include one or more faces, such that at least one of the first end  31  and the second end  35  can have a polygonal cross-section. 
     The first end  31  can include a driving engagement  32  for driving the OPC drum  10  during the image forming process. The driving engagement  32  can be sized, shaped, oriented, and/or otherwise disposed such that the grounding shaft  30  can be driven during the image forming process. Thus, although the drawings show certain preferred shapes of the driving engagement  32 , it is to be understood that the driving engagement  32  can be of any shape, so long as the driving engagement  32  can be used to drive the OPC drum  10 . The second end  35  can include a contact portion  36  that can contact a portion of the grounding plate  40  to achieve electrical connection therewith. 
     As shown in the drawings, the grounding plate  40  can include one or more outwardly extending contacts  41  to achieve electrical connection with the one or more contact areas  16  of the OPC drum  10 , and can include one or more inwardly extending contacts  42  to achieve electrical connection with the grounding shaft  30 . 
     The outwardly extending contacts  41  can be sized, shaped, and/or oriented, and the number of the contacts  41  can be chosen, such that the desired electrical connection can be achieved with the one or more contact areas  16  of the OPC drum  10 . 
     As discussed above, the inwardly extending contacts  42  can contact the contact portion  36  of the grounding shaft  30  inserted through the grounding shaft opening  27  of the flange  20 . Similar to the contacts  41 , one or more attributes of the contacts  42  can be chosen such that the desired electrical connection can be achieved between the grounding plate  40  and the grounding shaft  30 . 
     Further, one or more of the attributes of the contacts  42  can be chosen such that an interference fit can be achieved between the grounding plate  40  and the grounding shaft  30 . Specifically, in certain preferred embodiments of the present invention, the inwardly extending contacts  42  can achieve an interference fit with the contact portion  36  of the grounding shaft  30 . 
     The grounding plate  40  can also include one or more alignment voids (not shown) corresponding to the one or more grounding alignment posts of the flange  20  to aid in assembly of the coupling arrangement  100 . Preferably, a center portion  43  of the grounding plate  40  can include a plurality of alignment voids having an “x” or cross-shaped cross-section that corresponds to the cross-section of the grounding alignment posts of the flange  20 . The grounding plate  40  can also include a variety of materials that can achieve the desired electrical connection. Examples of such materials can include a metal or a metal coating such as copper, iron, aluminum, and/or phosphor bronze. 
     Thus, by the above arrangement, grounding of the OPC drum  10  (i.e., grounding of the grounding plate  40  with the drum interior surface  12  of the OPC drum  10 , and grounding of the grounding plate  40  with the grounding shaft  30 ) can be achieved. 
     Methods of assembling the coupling arrangement  100  according to the present invention can include inserting the flange  20  having the at least one receiving portion  27  in the first open end  14  of the OPC drum  10 . The at least one protrusion  17  can be formed on the OPC drum  10 , such that the at least one protrusion  17  can be received in the corresponding receiving portion  28  of the flange  20 . 
     The at least one protrusion  17  can be formed by a punching operation, wherein the OPC drum  10  can be punched to form the at least one protrusion  17 . In certain preferred embodiments of the invention, one or more of the drum exterior and interior surfaces  11  and  12  can be punched to plastically deform at least the drum interior surface  12  and subsequently to form the at least one protrusion  17 , and/or can be punched through the drum exterior and interior surfaces  11  and  12  to form the at least one protrusion  17 . One or more of the drum exterior and interior surfaces  11  and  12  can be punched with a tool having a shape corresponding to a shape of the at least one receiving portion  28  of the flange  20 . 
     Methods of assembling the coupling arrangement  100  can include orienting the flange  20 , and/or orienting the receiving portion  28  of the flange  20 , to a predetermined position. In certain preferred embodiments of the invention, the flange  20  can include a guide portion  29 , with which the flange  20  and the receiving portion  28  are oriented with respect to. Preferably, the guide portion  29  can include one or more posts that can be detected by a detector, and more preferably that can be detected by a mechanical detector (such that the guide portion  29  acts as a mechanical stop) and/or by a light detector (such as a laser beam). Thus, it is understood that the method of assembling the coupling arrangement  100  can be automated, and can be performed by an apparatus that can orient the at least one receiving portion  28  of the flange  20  to a predetermined position, and form the at least one protrusion  17  in the OPC drum  10 , such that the at least one protrusion  17  of the OPC drum  10  can be disposed in the at least one receiving portion  28  of the flange  20 . 
     As shown in  FIG. 5 , the assembled coupling arrangement  100  can be disposed in an electro-photographic machine  200 , such as a photocopier. In a preferred embodiment of the invention, the coupling arrangement  100  can be disposed in a process cartridge  300  (e.g., the coupling arrangement  100  and a flange for connection with the electro-photographic machine  200 ) adapted to be removably mounted to the electro-photographic machine  200 , and more specifically can be configured to mount to a main portion  210  of the electro-photographic machine.