Patent Publication Number: US-8989632-B2

Title: Toner anti-bridging agitator for an image forming device

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application Ser. No. 61/620,403, filed Apr. 4, 2012, entitled “Toner Anti-Bridging Agitator for an Imaging Device,” the content of which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     1. Field of the Disclosure 
     The present disclosure relates generally to electrophotographic image forming devices and more particularly to an anti-bridging agitator for an image forming device. 
     2. Description of the Related Art 
     In toner cartridge design, it is now common to separate components having a longer life from those having a shorter life into separate replaceable units. Relatively longer life components such as a developer roll, a toner adder roll, a doctor blade and a photoconductive drum are positioned in one replaceable unit (an “imaging unit”). The image forming device&#39;s toner supply, which is consumed relatively quickly in comparison with the components housed in the imaging unit, is provided in a reservoir in a separate replaceable unit in the form of a toner cartridge that mates with the imaging unit. In this configuration, the number of components housed in the toner cartridge is reduced in comparison with traditional toner cartridges. 
     To deliver toner from the toner cartridge to the imaging unit, an auger in the toner cartridge may be used to feed toner from an exit port on the toner cartridge into an entrance port on a developer unit of the imaging unit. The developer unit may include a second auger in proximity to the entrance port that disperses the toner within the developer unit. While the toner cartridge and the imaging unit are in high temperature storage or shipping conditions, toner stored therein may tend to clump together. When the toner cartridge and imaging unit are then installed in an image forming device, the clumped toner may form a bridge that disrupts or blocks toner flow from the toner cartridge to the imaging unit. Accordingly, a mechanism for keeping the pathway from the toner cartridge to the imaging unit free from packed toner is desired in order to improve toner delivery. 
     SUMMARY 
     A removable unit for an electrophotographic image forming device according to one example embodiment includes a housing having an inner volume forming a toner reservoir and a channel for accumulating toner. An auger advances toner within the channel and has a rotational axis and a flight. An agitator is mounted on an inner surface of the housing and is positioned to extend toward the auger. The agitator has a first segment and a second distal segment connected to the first segment. When the auger rotates, the flight of the auger engages the agitator causing movement of the second distal segment to push toner accumulated in the channel into the auger. 
     A toner conveyance assembly for an electrophotographic image forming device according to one example embodiment includes a channel for accumulating toner. An auger advances toner within the channel and has a rotational axis and a flight. An agitator is positioned to extend towards the auger. The agitator has a first segment and a second distal segment connected to the first segment. When the auger rotates, the flight of the auger engages the agitator causing movement of the second distal segment to push toner accumulated in the channel into the auger. 
     An agitator for a toner delivery device according to one example embodiment includes a base for mounting on an inner surface of a housing of the toner delivery device. A resiliently deflectable first segment is connected to the base. A second distal segment is connected to the first segment. The first segment and the second distal segment are positioned to extend toward an auger of the toner delivery device and engage a flight of the auger when the auger rotates causing movement of the second distal segment to push toner into the auger. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings incorporated in and forming a part of the specification, illustrate several aspects of the present disclosure, and together with the description serve to explain the principles of the present disclosure. 
         FIG. 1  is a block diagram of an imaging system according to one example embodiment. 
         FIG. 2  is a perspective view of a toner cartridge and an imaging unit of  FIG. 1  according to one example embodiment. 
         FIG. 3  is an exploded view of the toner cartridge shown in  FIG. 2 . 
         FIG. 4  is a perspective view of a toner exit port of the toner cartridge shown in  FIG. 2 . 
         FIG. 5  is a perspective view of a toner entrance port of a developer unit of the imaging unit shown in  FIG. 2 . 
         FIG. 6  is a cutaway view of the exit port of the toner cartridge of  FIG. 4  in communication with the entrance port of the developer unit of  FIG. 5 . 
         FIG. 7  is a perspective view of an agitator according to one example embodiment. 
         FIGS. 8A and 8B  are a side view and a front view, respectively, of the agitator shown in  FIG. 7  positioned to engage an auger of the toner cartridge. 
         FIG. 9  is a perspective view of an agitator according to a second example embodiment. 
         FIGS. 10A and 10B  are sectional front views of a portion of the toner cartridge of  FIG. 2  showing the agitator of  FIG. 9  at different moments of operation. 
         FIG. 11  is a perspective view of a portion of the developer unit of  FIG. 2  showing an agitator according to another example embodiment. 
         FIG. 12  is a top perspective view of the agitator of  FIG. 11  engaging a cam surface of a shutter. 
         FIGS. 13A and 13B  are front views showing the agitator of  FIG. 11  engaging an auger of the developer unit at different moments of operation. 
         FIG. 14  is a perspective view showing an alternative embodiment of a side-to-side sliding agitator. 
         FIGS. 15A and 15B  are cutaway illustrations of a first side and a second side of a paddle, respectively, having a cam surface for engaging a pin of the side-to-side sliding agitator of  FIG. 14 . 
         FIG. 16  shows an alternative embodiment of an up and down sliding agitator. 
         FIGS. 17A-C  show an alternative embodiment of an oscillating agitator;  FIG. 17A  shows an oscillating agitator positioned to engage an auger;  FIGS. 17B and 17C  show the agitator of  FIG. 17A  at different moments of operation. 
         FIG. 18  is a side view of an alternative embodiment of an agitator according to another example embodiment. 
         FIG. 19  shows an alternative embodiment of a plurality of rotatable agitators. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, reference is made to the accompanying drawings where like numerals represent like elements. The embodiments are described in sufficient detail to enable those skilled in the art to practice the present disclosure. It is to be understood that other embodiments may be utilized and that process, electrical, and mechanical changes, etc., may be made without departing from the scope of the present disclosure. Examples merely typify possible variations. Portions and features of some embodiments may be included in or substituted for those of others. The following description, therefore, is not to be taken in a limiting sense and the scope of the present disclosure is defined only by the appended claims and their equivalents. 
     Referring now to the drawings and more particularly to  FIG. 1 , there is shown a block diagram depiction of an imaging system  20  according to one example embodiment. Imaging system  20  includes an image forming device  22  and a computer  24 . Image forming device  22  communicates with computer  24  via a communications link  26 . As used herein, the term “communications link” generally refers to any structure that facilitates electronic communication between multiple components and may operate using wired or wireless technology and may include communications over the Internet. 
     In the example embodiment shown in  FIG. 1 , image forming device  22  is a multifunction machine (sometimes referred to as an all-in-one (AIO) device) that includes a controller  28 , a print engine  30 , a laser scan unit (LSU)  31 , an imaging unit  32 , a toner cartridge  35 , a user interface  36 , a media feed system  38  and media input tray  39  and a scanner system  40 . Image forming device  22  may communicate with computer  24  via a standard communication protocol, such as for example, universal serial bus (USB), Ethernet or IEEE 802.xx. Image forming device  22  may be, for example, an electrophotographic printer/copier including an integrated scanner system  40  or a standalone electrophotographic printer. 
     Controller  28  includes a processor unit and associated memory  29  and may be formed as one or more Application Specific Integrated Circuits (ASICs). Memory  29  may be any volatile or non-volatile memory or combination thereof such as, for example, random access memory (RAM), read only memory (ROM), flash memory and/or non-volatile RAM (NVRAM). Alternatively, memory  29  may be in the form of a separate electronic memory (e.g., RAM, ROM, and/or NVRAM), a hard drive, a CD or DVD drive, or any memory device convenient for use with controller  28 . Controller  28  may be, for example, a combined printer and scanner controller. 
     the example embodiment illustrated, controller  28  communicates with print engine  30  via a communications link  50 . Controller  28  communicates with imaging unit  32  and processing circuitry  44  thereon via a communications  51 . Controller  28  communicates with toner cartridge  35  and processing circuitry  45  therein via a communications link  52 . Controller  28  communicates with media feed system  38  via a communications link  53 . Controller  28  communicates with scanner system  40  via a communications link  54 . User interface  36  is communicatively coupled to controller  28  via a communications link  55 . Processing circuitry  44 ,  45  may provide authentication functions, safety and operational interlocks, operating parameters and usage information related to imaging unit  32  and toner cartridge  35 , respectively. Controller  28  processes print and scan data and operates print engine  30  during printing and scanner system  40  during scanning. 
     Computer  24 , which is optional, may be, for example, a personal computer, including memory  60 , such as RAM, ROM, and/or NVRAM, an input device  62 , such as a keyboard and/or a mouse, and a display monitor  64 . Computer  24  also includes a processor, input/output (I/O) interfaces, and may include at least one mass data storage device, such as a hard drive, a CD-ROM and/or a DVD unit (not shown). Computer  24  may also be a device capable of communicating with image forming device  22  other than a personal computer such as, for example, a tablet computer, a smartphone, or other electronic device. 
     In the example embodiment illustrated, computer  24  includes in its memory a software program including program instructions that function as an imaging driver  66 , e.g., printer/scanner driver software, for image forming device  22 . Imaging driver  66  is in communication with controller  28  of image forming device  22  via communications link  26 . Imaging driver  66  facilitates communication between image forming device  22  and computer  24 . One aspect of imaging driver  66  may be, for example, to provide formatted print data to image forming device  22 , and more particularly to print engine  30 , to print an image. Another aspect of imaging driver  66  may be, for example, to facilitate the collection of scanned data from scanner system  40 . 
     In some circumstances, it may be desirable to operate image forming device  22  in a standalone mode. In the standalone mode, image forming device  22  is capable of functioning without computer  24 . Accordingly, all or a portion of imaging driver  66 , or a similar driver, may be located in controller  28  of image forming device  22  so as to accommodate printing and/or scanning functionality when operating in the standalone mode. 
     Print engine  30  includes laser scan unit (LSU)  31 , toner cartridge  35 , imaging unit  32 , and a fuser  37 , all mounted within image forming device  22 . Imaging unit  32  is removably mounted in image forming device  22  and includes a developer unit  34  that houses a toner reservoir (or toner sump) and a toner delivery system. The toner delivery system includes a toner adder roll that provides toner from the toner sump to a developer roll. A doctor blade provides a metered uniform layer of toner on the surface of the developer roll. Imaging unit  32  also includes a cleaner unit  33  that houses a photoconductive drum and a waste toner removal system. Toner cartridge  35  is also removably mounted in imaging unit  32  in a mating relationship with developer unit  34  of imaging unit  32 . An exit port on toner cartridge  35  communicates with an entrance port on developer unit  34  allowing toner to be periodically transferred from a reservoir in toner cartridge  35  to resupply the toner sump in developer unit  34 . 
     The electrophotographic printing process is well known in the art and, therefore, is described briefly herein. During a printing operation, laser scan unit  31  creates a latent image on the photoconductive drum in cleaner unit  33 . Toner is transferred from the toner sump in developer unit  34  to the latent image on the photoconductive drum by the developer roll to create a toned image. The toned image is then transferred to a media sheet received in imaging unit  32  from media input tray  39  for printing. Toner remnants are removed from the photoconductive drum by the waste toner removal system. The toner image is bonded to the media sheet in fuser  37  and then sent to an output location or to one or more finishing options such as a duplexer, a stapler or a hole-punch. 
     Referring now to  FIG. 2 , a toner cartridge  200  and an imaging unit  300  are shown according to one example embodiment. Imaging unit  300  includes a developer unit  301  and a cleaner unit  302  mounted on a common frame  303 . As discussed above, imaging unit  300  and toner cartridge  200  are each removably installed in image forming device  22 . Imaging unit  300  is first slidably inserted into image forming device  22 . Toner cartridge  200  is then inserted into image forming device  22  and onto frame  303  in a mating relationship with developer unit  301  of imaging unit  300  as indicated by the arrow shown in  FIG. 2 . This arrangement allows toner cartridge  200  to be removed and reinserted easily when replacing an empty toner cartridge without having to remove imaging unit  300 . Imaging unit  300  may also be readily removed as desired in order to maintain, repair or replace the components associated with developer unit  301 , cleaner unit  302  or frame  303  or to clear a media jam. 
     Referring now to  FIG. 3 , toner cartridge  200  includes a housing  202  having an enclosed reservoir  220  for holding a quantity of toner therein. Housing  202  may be viewed as having a top or lid  204  mounted on a base  206 . Base  206  is formed by first and second side walls  214 ,  216  connected to adjoining front and rear walls  208 ,  209  and bottom  207 . In one embodiment, top  204  is ultrasonically welded to base  206  thereby forming enclosed reservoir  220 . First and second end caps  210 ,  212  are mounted to side walls  214 ,  216 , respectively. First and second end caps  210 ,  212  may be snap fitted into place or attached by screws or other fasteners. First and second end caps  210 ,  212  each include guides  226  to assist the insertion of toner cartridge  200  into image forming device  22  for mating with developer unit  301 . Various gears are housed within a space formed between first end cap  210  and first side wall  214 . At least a portion of a main interface gear  218  is exposed between first end cap  210  and first side wall  214  at the front of toner cartridge  200  to allow main interface gear  218  to engage with a drive system in imaging apparatus  22  that provides torque to main interface gear  218 . As a result, first side wall  214  may be referred to as the “drive” or “driven” side of toner cartridge  200 . Various interlocks and/or linkages may be housed within the space formed between second end cap  212  and second side wall  216 . A paddle  260  is rotatably mounted within toner reservoir  220 . First and second ends of a drive shaft  262  of paddle  260  extend through aligned openings (not shown) in first and second side walls  214 ,  216 , respectively. A drive gear  224  is provided on the first end of drive shaft  262  that engages with main interface gear  218  either directly or via one or more intermediate gears. 
     A channel  240  extends along the width of front wall  208  between first and second side walls  214 ,  216 . In one embodiment, channel  240  is positioned above the axis of rotation of drive shaft  262  of paddle  260 . Channel  240  may be integrally molded as part of front wall  208  or be formed as a separate component attached to front wall  208 . Channel  240  is generally horizontal when toner cartridge  200  is installed in image forming device  22 . An auger  230  having first and second ends  232 ,  234 , and a spiral screw flight  236  is positioned within and extends along the length of channel  240 . First end  232  of auger  230  extends through a bushing  238  ( FIG. 6 ) in first side wail  214 . A drive gear (not shown) is positioned on first end  232  of auger  230  that engages with main interface gear  218  either directly or via one or more intermediate gears. 
     Channel  240  includes an open portion or trough  242  and a substantially enclosed portion  244 . Trough  242  is open to toner reservoir  220  and extends from first side wall  214  toward second side wall  216 . Enclosed portion  244  of channel  240  extends from second side wall  216  and encloses second end  234  of auger  230 . As paddle  260  rotates, it delivers toner from toner reservoir  220  into trough  242 . With reference to  FIGS. 3 and 4 , auger  230  is rotated via the drive gear on first end  232  of auger  230  to deliver toner received in channel  240  to a shutter  270  housed in enclosed portion  244  of channel  240 . Shutter  270  regulates whether toner is permitted to exit toner cartridge  200  through an exit port  256  provided in front wall  208  and shown in  FIG. 4 . Exit port  256  is disposed at the bottom of channel  240  so that gravity will assist in exiting toner through exit port  256 . 
     With reference to  FIGS. 5 and 6 , developer unit  301  includes a housing  304  having a toner sump  305  formed by a rear wall  306 , first and second side walls  308 ,  310  and a bottom (not shown). A channel  340  extends along the width of and near the top of rear wall  306 . Channel  340  may be integrally molded as part of rear wall  306  or be formed as a separate component attached to rear wall  306 . An auger  330  having first and second ends  332 ,  334 , and a spiral screw flight  336  is positioned within and extends along the length of channel  340 . First end  332  of auger  330  extends through first side wall  308 . A drive gear (not shown) is positioned on first end  332  of auger  330  that engages with an input coupler  309  ( FIG. 2 ) of developer unit  301  either directly or via one or more intermediate gears. Input coupler  309  receives torque at its axial end from a drive system in image forming device  22  to drive various rotatable components in developer unit  301  including auger  330 . 
     Channel  340  includes an open portion or trough  342  and a substantially enclosed portion  344 . Trough  342  is open to toner sump  305  and extends from first side wall  308  toward second side wall  310 . Enclosed portion  344  of channel  340  extends from second side wall  310  and encloses second end  334  of auger  330 . An entrance port  356  is provided through a wall  358  of enclosed portion  344  of channel  340 . Entrance port  356  of developer unit  301  aligns with exit port  256  of toner cartridge  200  when toner cartridge  200  is installed on frame  303  and mated with imaging unit  300 . As illustrated in  FIG. 5 , entrance port  356  is disposed at the top of channel  340  so that gravity will assist toner entry into developer unit  301 . In one example form, entrance port  356  is larger in area than exit port  256  to prevent bridging by the toner exiting toner cartridge  200  and entering developer unit  301 . 
     A shutter  370  positioned in enclosed portion  344  of channel  340  regulates whether toner is permitted to enter developer unit  301  through entrance port  356 . Second end  334  of auger  330  extends into shutter  370  allowing auger  330  to distribute the incoming toner along channel  340 . Trough  342  includes a plurality of openings (not shown) spaced along its length. The openings extend through a bottom portion of trough  342 . Auger  330  is rotated via the drive gear on first end  332  of auger  330  to distribute toner received from exit port  256  of toner cartridge  200  along the length of trough  342 . The openings in trough  342  allow incoming toner to be distributed substantially evenly into toner sump  305 . Channel  340  is disposed above toner sump  305  allowing the entering toner to drop into toner sump  305 . 
       FIG. 6  illustrates the toner flow path (shown as the solid arrow labeled “TFP”) between toner cartridge  200  and developer unit  301 . In operation, toner is first passed from reservoir  220  to channel  240  by paddle  260 . Auger  230  then advances the toner through shutter  270  and out exit port  256 . The toner falls via gravity from exit port  256  into entrance port  356  of developer unit  301 . The toner is passed through shutter  370  and distributed along channel  340  by auger  330 . The toner then drops through the openings in trough  342  into toner sump  305  where it is held for use by developer unit  301 , Shutters  270 ,  370  of toner cartridge  200  and developer unit  301  are moved from closed positions to open positions as toner cartridge  200  is mated with imaging unit  300  to allow toner to flow from toner cartridge  200  to developer unit  301 . Shutters  270 ,  370  are moved from open positions to closed positions as toner cartridge  200  is separated from imaging unit  300  in order to prevent toner leakage from toner cartridge  200  or developer unit  301 . 
     As discussed above, toner under high temperature storage or shipping conditions may tend to clump or bridge in channels  240 ,  340  above augers  230 ,  330 . In some instances, the clumped or bridged toner may block additional toner from being transported through channel  240  or channel  340  potentially causing toner starvation. To address this potential problem, an agitator is provided in channel  240  of toner cartridge  200  and/or channel  340  of developer unit  301  to break up any clumped toner.  FIGS. 6 and 7  show one example agitator  400 . Agitator  400  includes a base  402  that mounts to an inner surface of housing  202  above channel  240  as shown in  FIG. 6 . Agitator  400  may also be provided in developer unit  301  as desired by mounting base  402  to an inner surface of housing  304  above channel  340 . A resiliently deflectable member  404  extends in a cantilevered manner from base  402 . Deflectable member  404  includes a first segment  404 A that connects to base  402  and a second segment  404 B connected to the distal end of first segment  404 A. In one embodiment, first segment  404 A extends from base  402  in the form of a resiliently deflectable arm and second segment  404 B forms a tab or paddle on the end of first segment  404 A. In this embodiment, second segment  404 B has a substantially planar undersurface  410  for pushing toner toward auger  230  as discussed below. In the example embodiment shown in  FIG. 7 , agitator  400  attaches to housing  202  or housing  304  via a fastener (not shown) mounted through a fastener hole  408  in base  402 ; however, agitator  400  may be mounted by any suitable method such as, for example by an adhesive applied between base  402  and housing  202  or housing  304 . 
       FIGS. 8A and 8B  show a side view and a front view, respectively, of agitator  400  mounted relative to auger  230 . As illustrated in  FIG. 8A , in the example embodiment illustrated, first segment  404 A extends from base  402  in a substantially vertical direction relative to cartridge  200  and is laterally offset from the rotational axis  231  of auger  230 . As shown in  FIG. 8B , first segment  404 A has an arcuate profile that engages flight  236  of auger  230  like a cam. The arcuate profile of first segment  404 A has a radius that is sized to span a pitch  236 P of flight  236  of auger  230 . The arcuate profile allows first segment  404 A to maintain contact with auger  230  as auger  230  rotates preventing agitator  400  from floating and vibrating thereby reducing the likelihood of undesired noise. Second segment  404 B extends away from first segment  404 A along a plane that is transverse to the rotational axis  231  of auger  230  such that second segment  404 B forms an acute angle Θ with respect to the rotational axis  231  of auger  230  when agitator  400  is in its free state. This enables agitator  400  to have a larger working area for disturbing clumped toner. In one example embodiment, undersurface  410  forms an angle Θ of about 45 degrees with respect to the rotational axis  231  of the auger  230  when agitator  400  is in its free state. 
     Agitator  400  extends into the rotational path of auger  230  such that deflectable member  404  oscillates up and down as auger  230  rotates in order to break up any clumped or bridged toner in channel  240 . Specifically, as auger  230  rotates, first segment  404 A of deflectable member  404  rides up and down the roots  237 A and crests  237 B of flight  236 . When first segment  404 A contacts a crest  237 B, first segment  404 A temporarily deflects causing second segment  404 B to travel away from auger  230 . As auger  230  rotates further and first segment  404 A returns to a root  237 A, second segment  404 B travels back toward auger  230 . The oscillating movement of agitator  400  allows second segment  404 B to serve as a paddle to push toner accumulating above channel  240  toward auger  230  so that the toner may be moved by auger  230 . 
       FIG. 9  shows another example embodiment of an agitator  450  that includes a plurality of resiliently deflectable members  404 - 1 ,  404 - 2 ,  404 - 3 ,  404 - 4 , each having a form similar to deflectable member  404  of agitator  400  and formed unitarily with an elongated base  452 . It is understood that agitator  450  may include any number of deflectable members as desired. With reference to  FIGS. 10A and 10B , agitator  450  is shown mounted on an inner surface of housing  202  such as an inner surface of top  204 . Of course agitator  450  may also be mounted to housing  304  of developer unit  301  as desired. Agitator  450  is positioned to generally extend toward auger  230  such that a longitudinal axis of agitator  450  is substantially parallel to the rotational axis  231  of auger  230 . Like agitator  400  discussed above, each of the first segments  404 A of resiliently deflectable members  404 - 1 ,  404 - 2 ,  404 - 3 ,  404 - 4  extends from elongated base  452  in a cantilevered manner and has an arcuate profile sized to span a pitch  236 P of flight  236  of auger  230 . As a result, each of the first segments  404 A is positioned to maintain contact with auger  230  as auger  230  rotates. Further, in order to maintain a more constant torque on auger  230 , resiliently deflectable members  404 - 1 ,  404 - 2 ,  404 - 3 ,  404 - 4  are preferably spaced apart from each other and arranged such that adjacent members  404 - 1 ,  404 - 2 ,  404 - 3 ,  404 - 4  are not lifted at the same time. For example, as shown in  FIG. 10A , when first segments  404 A of resiliently deflectable members  404 - 2  and  404 - 4  engage a crest  237 B of auger  230 , the immediately adjacent resiliently deflectable members  404 - 1  and  404 - 3  engage a root  237 A of auger  230 . As auger  230  rotates to a second position shown in  FIG. 10B , resiliently deflectable members  404 - 1  and  404 - 3  engage a crest  237 B and resiliently deflectable members  404 - 2  and  404 - 4  engage a root  237 A. Torque variation is preferably minimized in order to reduce the load on a motor in image forming device  22  that drives auger  230 . If resiliently deflectable members  404 - 1 ,  404 - 2 ,  404 - 3 ,  404 - 4  were positioned to rise and fall at the same time, the torque on auger  230  would be higher when resiliently deflectable members  404 - 1 ,  404 - 2 ,  404 - 3 ,  404 - 4  raised and lower when resiliently deflectable members  404 - 1 ,  404 - 2 ,  404 - 3 ,  404 - 4  fell. 
       FIGS. 11-13B  show an agitator  500  according to another example embodiment for use in developer unit  301 . As shown in  FIG. 11 , agitator  500  is positioned to extend through an aperture  346  in enclosed portion  344  of channel  340  and into an aperture  374  in shutter  370  to agitate toner in an area that otherwise may be particularly susceptible to clogging. With reference to  FIG. 12 , agitator  500  includes a base  512  and a resiliently deflectable member  501  that extends from base  512 . In the example embodiment illustrated, base  512  attaches to housing  304  by a fastener (not shown) mounted through a fastener hole  514 ; however, it will be appreciated that base  512  may be attached by any suitable method. In this embodiment, base  512  further includes a locating hole  516  that receives a corresponding peg on housing  304  to ensure that base  512  is located accurately relative to housing  304 . Of course this configuration may be reversed as desired such that base  512  includes a locating peg and housing  304  includes a corresponding hole or recess. Resiliently deflectable member  501  includes a connecting segment  502  that extends from base  512  in a cantilevered manner. As shown in  FIG. 11 , connecting segment  502  curves around the front of channel  340  to a position above auger  330 . An arm segment  504  extends from connecting segment  502  above auger  330  toward shutter  370 . Arm segment  504  includes an arcuate profile that is sized and shaped to engage the flight  336  of auger  330  like first segment  404 A discussed above. A distal segment  506  extends from arm segment  504  above apertures  346  and  374 . In the example embodiment illustrated, distal segment  506  includes a protuberance  506 A that projects toward apertures  346  and  374  to push toner toward auger  330 . 
     With reference to  FIGS. 13A and 13B , like agitators  400  and  450 , agitator  500  is actuated by the rotation of auger  330 . Specifically, as auger  330  rotates, contact between arm segment  504  and auger  330  causes resiliently deflectable member  501  to deflect up and down. This oscillating motion causes protuberance  506 A of distal segment  506  to move into and out of apertures  346  and  374  to break up compacted toner and push toner toward auger  330 . With reference back to  FIG. 11 , a locating post  510  extends substantially perpendicularly from distal segment  506  to locate and limit the movement of distal segment  506  toward and away from apertures  346  and  374 . Locating post  510  extends over arcuate wall  348  of enclosed portion  344  of channel  340 . Arcuate wall  348  defines a hard stop position of locating post  510  thereby limiting further movement of distal segment  506  toward aperture  346 . With reference back to  FIG. 12 , shutter  370  includes a cam surface  376  that engages distal segment  506  when shutter  370  moves from the open position to the closed position in order to clear protuberance  506 A from aperture  374  to allow shutter  370  to close. 
       FIG. 14  shows a side-to-side sliding agitator  600  according to another example embodiment. Sliding agitator  600  includes a base  606  that spans along the length of channel  240  and/or  340  in front of or behind auger  230  and/or  330 . A plurality of fingers  602  extend from base  606  above auger  230  and/or  330 . In the example embodiment illustrated, fingers  602  have a substantially curved profile that wraps partly around the top of auger  230 . A pin  604  extends from base  606  into the path of a rotating member such as paddle  260  of toner cartridge  200 . As shown in  FIGS. 15A and 15B , in this embodiment, paddle  260  includes a pair of alternating cam surfaces  264 ,  266 , one on each radial end of paddle  260 . Specifically,  FIG. 15A  shows a first cam surface  264  on the first radial end  260 A of paddle  260 .  FIG. 15B  shows a second cam surface  266  on the second radial end  260 B of paddle  260 . First cam surface  264  and second cam surface  266  are inclined in opposite directions such that first cam surface  264  and second cam surface  266  engage pin  604  on opposite sides during the rotation of paddle  260 . As paddle  260  rotates, first cam surface  264  pushes pin  604  laterally to one side and second cam surface  266  pushes pin  604  laterally to the opposite side. This causes agitator  600  to oscillate back and forth from side to side to help break up compacted toner and to cause the toner to fall toward auger  230 . 
       FIG. 16  shows an up and down sliding agitator  650  according to one example embodiment. Agitator  650  includes an elongated body  652  that spans the length of channel  240  or  340  and has distal ends that are supported in respective vertical slots  654  on each side wall of toner cartridge  200  or developer unit  301 . Vertical slots  654  limit the movement of agitator  650  to substantially up and down only. A plurality of curved runners  656  extend downward from body  652  and ride on the flight  236  or  336  of auger  230  or  330 . As auger  230  or  330  rotates, runners  656  ride up and down the flight  236  or  336  lifting and lowering agitator  650 . This up and down motion agitates toner positioned above auger  230  or  330  causing it to fall toward auger  230  or  330  into channel  240  or  340 . It will be appreciated that runners  656  may have different shapes as desired so long as their engagement with flight  236  or  336  causes agitator  650  to oscillate up and down. 
       FIGS. 17A-C  show another example agitator  700 . In this embodiment, agitator  700  includes a rotatable member  701  that spans along the length of channel  240  or  340 . A plurality of spaced apart, substantially inverted V-shaped arms  702  extend radially from rotatable member  701 . A cam  704  is positioned near an end of auger  230  or  330  that engages arms  702  as auger  230  or  330  rotates. Specifically, as auger  230  or  330  rotates, cam  704  pushes arms  702  in an alternating manner causing agitator  700  to rotate about the longitudinal axis of rotatable member  701 . This causes arms  702  to rock from one side to the other in the area surrounding auger  230  as illustrated in  FIGS. 17B and 17C  to break up compacted toner. It will be appreciated that arms  702  may take on other shapes as desired. 
       FIG. 18  shows an additional example embodiment of an agitator. In this embodiment, auger  230  or  330  is provided with a plurality of fingers  750  extending radially therefrom. Fingers  750  are formed of a flexible and resilient material. As auger  230  or  330  rotates in the direction indicated in  FIG. 18 , fingers  750  positioned adjacent to the open area above channel  240  or  340  extend from the top of auger  230  or  330  upwardly and outwardly to break up any compacted toner above auger  230  or  330 . As auger  230  or  330  rotates further, fingers  750  bend as they ride into trough  242  or  342 . 
       FIG. 19  shows another example embodiment in the form of rotating agitators  800 . Each agitator  800  rotates about an axis of rotation  802  and includes one or more projections or teeth  804  that extend outwardly from agitator  800 . Agitators  800  are driven by auger  230  or  330  such that as auger  230  or  330  rotates (in the direction indicated by the arrow below auger  230  in  FIG. 19 ), teeth  804  are displaced by flight  236  or  336  causing agitators  800  to rotate about their respective axes  802  (as indicated in  FIG. 19 ). This rotation causes teeth  804  to break up toner positioned above channel  240  or  340  causing the toner to fall toward auger  230  or  330 . 
     The foregoing description illustrates various aspects of the present disclosure. It is not intended to be exhaustive. Rather, it is chosen to illustrate the principles of the present disclosure and its practical application to enable one of ordinary skill in the art to utilize the present disclosure, including its various modifications that naturally follow. All modifications and variations are contemplated within the scope of the present disclosure as determined by the appended claims. Relatively apparent modifications include combining one or more features of various embodiments with features of other embodiments.