Patent Publication Number: US-11378897-B2

Title: Toner container having an encoded member and an alignment guide for locating a sensor relative to the encoded member

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This application is a continuation application of U.S. patent application Ser. No. 16/820,962, filed Mar. 17, 2020, entitled “Toner Container Having an Encoded Member and an Alignment Guide for Locating a Sensor Relative to the Encoded Member,” which is a continuation-in-part application of U.S. patent application Ser. No. 16/690,203, filed Nov. 21, 2019, now U.S. Pat. No. 10,859,944, issued Dec. 8, 2020, entitled “Toner Container Having a Common Input Gear for a Toner Agitator Assembly and an Encoded Member,” which is a continuation application of U.S. patent application Ser. No. 16/157,495, filed Oct. 11, 2018, now U.S. Pat. No. 10,527,967, issued Jan. 7, 2020, entitled “Toner Container Having a Common Input Gear for a Toner Agitator Assembly and an Encoded Member.” U.S. patent application Ser. No. 16/820,962, filed Mar. 17, 2020, entitled “Toner Container Having an Encoded Member and an Alignment Guide for Locating a Sensor Relative to the Encoded Member” also claims priority to U.S. Provisional Patent Application Ser. No. 62/822,088, filed Mar. 22, 2019, entitled “Toner Container Having an Encoded Member and Positioning Features for Locating a Sensor Relative to the Encoded Member,” the content of which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     1. Field of the Disclosure 
     The present disclosure relates generally to image forming devices and more particularly to a toner container having an encoded member and an alignment guide for locating a sensor relative to the encoded member. 
     2. Description of the Related Art 
     In electrophotographic image forming devices, one or more replaceable toner containers may be used to supply toner for printing onto sheets of media. Each toner container often includes a toner agitator assembly that agitates and mixes toner stored in a toner reservoir to prevent the toner from clumping and that moves the toner to an outlet of the toner container. It is often desired for each toner container to communicate characteristics of the toner container to the image forming device for proper operation. For example, it may be desired to communicate such information as authentication or validation information, toner fill amount, toner color, toner type, etc. 
     SUMMARY 
     A toner container for use in an electrophotographic image forming device according to one example embodiment includes a housing having a top, a bottom, a front and a rear positioned between a first side and a second side of the housing of the toner container. The housing of the toner container has a reservoir for holding toner. An outlet on the front of the housing of the toner container is in fluid communication with the reservoir for exiting toner from the toner container. An input gear is positioned at the first side of the housing of the toner container for mating with a corresponding output gear in the image forming device when the toner container is installed in the image forming device. The toner container includes an encoded member that is encoded with identifying information of the toner container and that is operatively connected to the input gear such that rotation of the input gear causes movement of the encoded member for communicating the identifying information of the toner container to a sensor of the image forming device when the toner container is installed in the image forming device. At least a portion of the encoded member is exposed on the first side of the housing of the toner container. A first alignment guide on the first side of the housing of the toner container is positioned axially outboard of the encoded member relative to a rotational axis of the input gear and is positioned below an exposed portion of the encoded member. The first alignment guide includes a top surface that is unobstructed to contact a sensor housing in the image forming device from below when the toner container is installed in the image forming device. At least a portion of the top surface of the first alignment guide inclines upward and rearward toward the top and the rear of the housing of the toner container for contacting and lifting the sensor housing in the image forming device upward during insertion of the toner container into the image forming device with the front of the housing of the toner container leading the insertion for aligning the sensor of the image forming device with the exposed portion of the encoded member. 
     Embodiments include those wherein the encoded member is rotatably connected to the input gear such that rotation of the input gear causes rotation of the encoded member. In some embodiments, the encoded member is positioned on an axially outboard face of the input gear that faces away from the reservoir. In some embodiments, the top surface of the first alignment guide includes a front portion and a rear portion. The front portion of the top surface of the first alignment guide is positioned closer to the front of the housing of the toner container than the rear portion of the top surface of the first alignment guide is to the front of the housing of the toner container. The front portion of the top surface of the first alignment guide inclines upward and rearward toward the top and the rear of the housing of the toner container. At least a portion of the rear portion of the top surface of the first alignment guide is positioned higher than the rotational axis of the input gear. In some embodiments, at least a portion of the rear portion of the top surface of the first alignment guide extends rearward of the rotational axis of the input gear. 
     Embodiments include those wherein the first alignment guide extends outward sideways from the first side of the housing of the toner container. 
     Some embodiments include a second alignment guide on the first side of the housing of the toner container. In some embodiments, the second alignment guide includes a frontward facing surface that faces toward the front of the housing of the toner container. The frontward facing surface extends upward from a rear end of the top surface of the first alignment guide. The frontward facing surface is unobstructed to contact the sensor housing in the image forming device when the toner container is installed in the image forming device for limiting a position of the sensor of the image forming device in a direction from the front of the housing of the toner container toward the rear of the housing of the toner container. 
     In some embodiments, the second alignment guide includes a first guide surface and a second guide surface. The second guide surface is positioned rearward of the first guide surface such that the second guide surface is positioned closer to the rear of the housing of the toner container than the first guide surface is to the rear of the housing of the toner container. The first guide surface inclines outward sideways and rearward away from the first side and toward the rear of the housing of the toner container. The second guide surface inclines inward sideways and rearward toward the second side and toward the rear of the housing of the toner container. The first and second guide surfaces are unobstructed to contact the sensor housing in the image forming device during insertion of the toner container into the image forming device for moving the sensor housing in the image forming device axially relative to the rotational axis of the input gear during insertion of the toner container into the image forming device. In some embodiments, the second alignment guide leads rearward along the first side of the housing of the toner container to the exposed portion of the encoded member. In some embodiments, at least a portion of each of the first and second guide surfaces is positioned closer to the front of the housing of the toner container than the exposed portion of the encoded member is to the front of the housing of the toner container, and at least a portion of each of the first and second guide surfaces is positioned higher than a portion of the top surface of the first alignment guide. 
     A toner container for use in an electrophotographic image forming device according to another example embodiment includes a housing having a top, a bottom, a front and a rear positioned between a first side and a second side of the housing of the toner container. The housing of the toner container has a reservoir for holding toner. An outlet on the front of the housing of the toner container is in fluid communication with the reservoir for exiting toner from the toner container. An input gear is positioned at the first side of the housing of the toner container for mating with a corresponding output gear in the image forming device when the toner container is installed in the image forming device. The toner container includes an encoded member that is encoded with identifying information of the toner container and that is rotatably connected to the input gear such that rotation of the input gear causes rotation of the encoded member for communicating the identifying information of the toner container to a sensor of the image forming device when the toner container is installed in the image forming device. The encoded member is positioned on an axially outboard face of the input gear that faces away from the reservoir. A first alignment guide on the first side of the housing of the toner container is positioned axially outboard of the encoded member relative to a rotational axis of the input gear. The first alignment guide overlaps with the axially outboard face of the input gear as viewed from the first side of the housing of the toner container. The first alignment guide includes a top surface that is unobstructed to contact a sensor housing in the image forming device from below when the toner container is installed in the image forming device. At least a portion of the top surface of the first alignment guide inclines upward and rearward toward the top and the rear of the housing of the toner container for contacting and lifting the sensor housing in the image forming device upward during insertion of the toner container into the image forming device with the front of the housing of the toner container leading the insertion for aligning the sensor of the image forming device with the encoded member. 
     Embodiments include those wherein the top surface of the first alignment guide includes a front portion and a rear portion. The front portion of the top surface of the first alignment guide is positioned closer to the front of the housing of the toner container than the rear portion of the top surface of the first alignment guide is to the front of the housing of the toner container. The front portion of the top surface of the first alignment guide inclines upward and rearward toward the top and the rear of the housing of the toner container. At least a portion of the rear portion of the top surface of the first alignment guide is positioned higher than the rotational axis of the input gear. In some embodiments, at least a portion of the rear portion of the top surface of the first alignment guide extends rearward of the rotational axis of the input gear. 
     Embodiments include those wherein the first alignment guide extends outward sideways from the first side of the housing of the toner container. 
     Some embodiments include a second alignment guide on the first side of the housing of the toner container. In some embodiments, the second alignment guide includes a frontward facing surface that faces toward the front of the housing of the toner container. The frontward facing surface extends upward from a rear end of the top surface of the first alignment guide. The frontward facing surface is unobstructed to contact the sensor housing in the image forming device when the toner container is installed in the image forming device for limiting a position of the sensor of the image forming device in a direction from the front of the housing of the toner container toward the rear of the housing of the toner container. 
     In some embodiments, the second alignment guide includes a first guide surface and a second guide surface. The second guide surface is positioned rearward of the first guide surface such that the second guide surface is positioned closer to the rear of the housing of the toner container than the first guide surface is to the rear of the housing of the toner container. The first guide surface inclines outward sideways and rearward away from the first side and toward the rear of the housing of the toner container. The second guide surface inclines inward sideways and rearward toward the second side and toward the rear of the housing of the toner container. The first and second guide surfaces are unobstructed to contact the sensor housing in the image forming device during insertion of the toner container into the image forming device for moving the sensor housing in the image forming device axially relative to the rotational axis of the input gear during insertion of the toner container into the image forming device. In some embodiments, at least a portion of each of the first and second guide surfaces is positioned closer to the front of the housing of the toner container than the rotational axis of the input gear is to the front of the housing of the toner container, and at least a portion of each of the first and second guide surfaces is positioned higher than a portion of the top surface of the first alignment guide. 
     A toner container for use in an electrophotographic image forming device according to another example embodiment includes a housing having a top, a bottom, a front and a rear positioned between a first side and a second side of the housing of the toner container. The housing of the toner container has a reservoir for holding toner. An outlet on the front of the housing of the toner container is in fluid communication with the reservoir for exiting toner from the toner container. An input gear is positioned at the first side of the housing of the toner container for mating with a corresponding output gear in the image forming device when the toner container is installed in the image forming device. The toner container includes an encoded member that is encoded with identifying information of the toner container and that is operatively connected to the input gear such that rotation of the input gear causes movement of the encoded member for communicating the identifying information of the toner container to a sensor of the image forming device when the toner container is installed in the image forming device. At least a portion of the encoded member is exposed on the first side of the housing of the toner container. A first alignment guide on the first side of the housing of the toner container leads rearward along the first side of the housing of the toner container to the exposed portion of the encoded member. The first alignment guide includes a first guide surface that inclines outward sideways and rearward away from the first side and toward the rear of the housing of the toner container. The first guide surface is unobstructed to contact a sensor housing in the image forming device during insertion of the toner container into the image forming device with the front of the housing of the toner container leading the insertion for moving the sensor housing in the image forming device axially relative to a rotational axis of the input gear during insertion of the toner container into the image forming device. 
     Embodiments include those wherein the encoded member is rotatably connected to the input gear such that rotation of the input gear causes rotation of the encoded member. In some embodiments, the encoded member is positioned on an axially outboard face of the input gear that faces away from the reservoir. In some embodiments, at least a portion of the first guide surface is positioned closer to the front of the housing of the toner container than the rotational axis of the input gear is to the front of the housing of the toner container, and at least a portion of the first guide surface is positioned higher than the rotational axis of the input gear. 
     Embodiments include those wherein the first alignment guide includes a second guide surface that is positioned rearward of the first guide surface such that the second guide surface is positioned closer to the rear of the housing of the toner container than the first guide surface is to the rear of the housing of the toner container. The second guide surface inclines inward sideways and rearward toward the second side and toward the rear of the housing of the toner container. The second guide surface is unobstructed to contact the sensor housing in the image forming device during insertion of the toner container into the image forming device for moving the sensor housing in the image forming device axially relative to the rotational axis of the input gear during insertion of the toner container into the image forming device. 
     Some embodiments include a second alignment guide on the first side of the housing of the toner container. The second alignment guide is positioned axially outboard of the encoded member relative to the rotational axis of the input gear and is positioned below the exposed portion of the encoded member. The second alignment guide includes a top surface that is unobstructed to contact the sensor housing in the image forming device from below when the toner container is installed in the image forming device. At least a portion of the top surface of the second alignment guide inclines upward and rearward toward the top and the rear of the housing of the toner container for contacting and lifting the sensor housing in the image forming device upward during insertion of the toner container into the image forming device for aligning the sensor of the image forming device with the exposed portion of the encoded member. 
     Some embodiments further include a third alignment guide on the first side of the housing of the toner container. The third alignment guide includes a frontward facing surface that faces toward the front of the housing of the toner container. The frontward facing surface extends upward from a rear end of the top surface of the second alignment guide. The frontward facing surface is unobstructed to contact the sensor housing in the image forming device when the toner container is installed in the image forming device for limiting a position of the sensor of the image forming device in a direction from the front of the housing of the toner container toward the rear of the housing of the toner container. 
    
    
     
       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 according to one example embodiment. 
         FIG. 3  is a front perspective view of the toner cartridge shown in  FIG. 2 . 
         FIG. 4  is a rear perspective view of the toner cartridge shown in  FIGS. 2 and 3 . 
         FIG. 5  is an exploded view of the toner cartridge shown in  FIGS. 2-4  showing a toner agitator assembly of the toner cartridge according to one example embodiment. 
         FIG. 6  is a side elevation view of the toner cartridge shown in  FIGS. 2-5  showing an encoded member of the toner cartridge according to one example embodiment. 
         FIG. 7  is a side elevation view of the encoded member of the toner cartridge according to one example embodiment. 
         FIG. 8  is a side elevation view of a drive train of the toner cartridge according to one example embodiment. 
         FIG. 9  is a top plan view of a portion of the toner cartridge shown in  FIGS. 2-6  according to one example embodiment. 
         FIG. 10  is a side elevation view of a sensor assembly of an image forming device according to one example embodiment. 
         FIG. 11  is a top plan view of the sensor assembly shown in  FIG. 10 . 
         FIG. 12  is an exploded view of the sensor assembly shown in  FIGS. 10 and 11 . 
         FIG. 13  is a top plan view showing the position of the toner cartridge relative to the sensor assembly as the toner cartridge enters the image forming device according to one example embodiment. 
         FIG. 14  is a top plan view showing the position of the toner cartridge relative to the sensor assembly with the toner cartridge advanced further into the image forming device from the position shown in  FIG. 13  showing an axial alignment guide of the toner cartridge contacting a sensor housing of the sensor assembly. 
         FIGS. 15A and 15B  are a top plan view and a side elevation view, respectively, showing the position of the toner cartridge relative to the sensor assembly with the toner cartridge advanced further into the image forming device from the position shown in  FIG. 14 . 
         FIGS. 16A and 16B  are a top plan view and a side elevation view, respectively, showing the position of the toner cartridge relative to the sensor assembly with the toner cartridge advanced further into the image forming device from the position shown in  FIGS. 15A and 15B  showing a vertical alignment guide of the toner cartridge contacting the sensor housing of the sensor assembly. 
         FIGS. 17A and 17B  are a top plan view and a side elevation view, respectively, showing the position of the toner cartridge relative to the sensor assembly with the toner cartridge advanced further into the image forming device from the position shown in  FIGS. 16A and 16B . 
         FIGS. 18A and 18B  are a top plan view and a side elevation view, respectively, showing the position of the toner cartridge relative to the sensor assembly with the toner cartridge in its final installed position in the image forming device. 
     
    
    
     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 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  200 , a toner cartridge  100 , a user interface  36 , a media feed system  38 , a media input tray  39 , a scanner system  40 , a drive motor  70  and a sensor  300 . 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 electronic memory  29 . The processor may include one or more integrated circuits in the form of a microprocessor or central processing unit 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). Memory  29  may be in the form of a separate 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. 
     In the example embodiment illustrated, controller  28  communicates with print engine  30  via a communications link  50 . Controller  28  communicates with imaging unit  200  and processing circuitry  44  thereon via a communications link  51 . Controller  28  communicates with toner cartridge  100  and processing circuitry  45  thereon 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 . Controller  28  communicates with drive motor  70  via a communications link  56 . Controller  28  communicates with sensor  300  via a communications link  57 . Controller  28  processes print and scan data and operates print engine  30  during printing and scanner system  40  during scanning. Processing circuitry  44 ,  45  may provide authentication functions, safety and operational interlocks, operating parameters and usage information related to imaging unit  200  and toner cartridge  100 , respectively. Each of processing circuitry  44 ,  45  includes a processor unit and associated electronic memory. As discussed above, the processor may include one or more integrated circuits in the form of a microprocessor or central processing unit and may include one or more application-specific integrated circuits (ASICs). The memory may be any volatile or non-volatile memory or combination thereof or any memory device convenient for use with processing circuitry  44 ,  45 . 
     Computer  24 , which is optional, may be, for example, a personal computer, including electronic 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 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 a laser scan unit (LSU)  31 , toner cartridge  100 , imaging unit  200  and a fuser  37 , all mounted within image forming device  22 . Imaging unit  200  is removably mounted in image forming device  22  and includes a developer unit  202  that houses a toner reservoir and a toner development system. In one embodiment, the toner development system utilizes what is commonly referred to as a single component development system. In this embodiment, the toner development system includes a toner adder roll that provides toner from the toner reservoir of developer unit  202  to a developer roll. A doctor blade provides a metered uniform layer of toner on the surface of the developer roll. In another embodiment, the toner development system utilizes what is commonly referred to as a dual component development system. In this embodiment, toner in the toner reservoir of developer unit  202  is mixed with magnetic carrier beads. The magnetic carrier beads may be coated with a polymeric film to provide triboelectric properties to attract toner to the carrier beads as the toner and the magnetic carrier beads are mixed in the toner reservoir of developer unit  202 . In this embodiment, developer unit  202  includes a magnetic roll that attracts the magnetic carrier beads having toner thereon to the magnetic roll through the use of magnetic fields. Imaging unit  200  also includes a cleaner unit  204  that houses a photoconductive drum and a waste toner removal system. 
     Toner cartridge  100  is removably mounted in imaging forming device  22  in a mating relationship with developer unit  202  of imaging unit  200 . An outlet port on toner cartridge  100  communicates with an inlet port on developer unit  202  allowing toner to be periodically transferred from toner cartridge  100  to resupply the toner reservoir in developer unit  202 . 
     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  204 . Toner is transferred from the toner reservoir in developer unit  202  to the latent image on the photoconductive drum by the developer roll (in the case of a single component development system) or by the magnetic roll (in the case of a dual component development system) to create a toned image. The toned image is then transferred to a media sheet received by imaging unit  200  from media input tray  39  for printing. Toner may be transferred directly to the media sheet by the photoconductive drum or by an intermediate transfer member that receives the toner from the photoconductive drum. 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 , toner cartridge  100  and imaging unit  200  are shown according to one example embodiment. Imaging unit  200  includes a developer unit  202  and a cleaner unit  204  mounted on a common frame  206 . Developer unit  202  includes a toner inlet port  208  positioned to receive toner from toner cartridge  100 . As discussed above, imaging unit  200  and toner cartridge  100  are each removably installed in image forming device  22 . Imaging unit  200  is first slidably inserted into image forming device  22 . Toner cartridge  100  is then inserted into image forming device  22  and onto frame  206  in a mating relationship with developer unit  202  of imaging unit  200  as indicated by the arrow A shown in  FIG. 2 , which also indicates the direction of insertion of imaging unit  200  and toner cartridge  100  into image forming device  22 . This arrangement allows toner cartridge  100  to be removed and reinserted easily when replacing an empty toner cartridge  100  without having to remove imaging unit  200 . Imaging unit  200  may also be readily removed as desired in order to maintain, repair or replace the components associated with developer unit  202 , cleaner unit  204  or frame  206  or to clear a media jam. 
     With reference to  FIGS. 2-5 , toner cartridge  100  includes a housing  102  having an enclosed reservoir  104  ( FIG. 5 ) for storing toner. Housing  102  includes a top  106 , a bottom  107 , first and second sides  108 ,  109 , a front  110  and a rear  111 . Front  110  of housing  102  leads during insertion of toner cartridge  100  into image forming device  22  and rear  111  trails. In one embodiment, each side  108 ,  109  of housing  102  includes an end cap  112 ,  113  mounted, e.g., by fasteners or a snap-fit engagement, to side walls  114 ,  115  of a main body  116  of housing  102 . In this embodiment, housing  102  includes main body  116  as well as various attachments (direct and indirect) thereto forming the overall body of toner cartridge  100  including, for example, end caps  112 ,  113 . An outlet port  118  in fluid communication with reservoir  104  is positioned on front  110  of housing  102  near side  109  for exiting toner from toner cartridge  100 . Housing  102  may include legs  120  on bottom  107  to assist with the insertion of toner cartridge  100  into image forming device  22  and to support housing  102  when toner cartridge  100  is set on a flat surface. A handle  122  may be provided on top  106  or rear  111  of housing  102  to assist with insertion and removal of toner cartridge  100  into and out of image forming device  22 . 
     Sides  108 ,  109  may each include a positioning guide  124  that extends outward from the respective side  108 ,  109  to assist the insertion of toner cartridge  100  into image forming device  22 . Positioning guides  124  travel in corresponding guide slots in image forming device  22  that guide the insertion of toner cartridge  100  into image forming device  22 . In the example embodiment illustrated, a positioning guide  124  is positioned on the outer side of each end cap  112 ,  113 . Positioning guides  124  may run along a front-to-rear dimension  126  of housing  102 , which extends from front  110  to rear  111 , as shown in  FIGS. 3 and 4 . 
     With reference to  FIG. 5 , in the example embodiment illustrated, a toner agitator assembly  130  is rotatably positioned within toner reservoir  104 . Toner agitator assembly  130  includes an auger  132  having first and second ends  132   a ,  132   b  and a spiral screw flight. Auger  132  is positioned in a channel  128  that runs along the front  110  of housing  102  from side wall  114  to side wall  115 . Channel  128  is oriented generally horizontal when toner cartridge  100  is installed in image forming device  22 . Auger  132  includes a rotational axis  133 . In operation, auger  132  rotates in an operative rotational direction  138 . Rotation of auger  132  in operative rotational direction  138  delivers toner in channel  128  to outlet port  118 , which is positioned at the bottom of channel  128  so that gravity assists in exiting toner through outlet port  118 . Channel  128  includes an open portion  128   a  and may include an enclosed portion  128   b . Open portion  128   a  is open to toner reservoir  104  and extends from side wall  114  toward second end  132   b  of auger  132 . Enclosed portion  128   b  of channel  128  extends from side wall  115  and encloses second end  132   b  of auger  132 . In this embodiment, outlet port  118  is positioned at the bottom of enclosed portion  128   b  of channel  128 . 
     Toner agitator assembly  130  also includes a rotatable drive shaft  134  and one or more toner agitators  136  in the form of extensions outward from drive shaft  134 . Drive shaft  134  includes a rotational axis  135 . In the example embodiment illustrated, rotational axis  135  of drive shaft  134  is parallel to rotational axis  133  of auger  132 . In operation, drive shaft  134  rotates in an operative rotational direction  139 . Toner agitators  136  rotate with drive shaft  134  around rotational axis  135  when drive shaft  134  rotates in operative rotational direction  139 . As drive shaft  134  rotates in operative rotational direction  139 , toner agitators  136  agitate and mix the toner stored in toner reservoir  104  and, in the embodiment illustrated, move toner toward channel  128  where auger  132  moves the toner to outlet port  118 . In the example embodiment illustrated, first and second ends of drive shaft  134  extend through aligned openings in side walls  114 ,  115 , respectively. However, drive shaft  134  may take other positions and orientations as desired. Bushings may be provided on an inner side of each side wall  114 ,  115  where drive shaft  134  passes through side walls  114 ,  115 . 
     A drive train  140  on housing  102  is operatively connected to auger  132  and drive shaft  134  and may be positioned within a space formed between end cap  112  and side wall  114 . Drive train  140  includes an input gear  142  that engages with a corresponding output gear in image forming device  22  that provides rotational motion from drive motor  70  in image forming device  22  to input gear  142 . Input gear  142  is rotatable about a rotational axis  141 . In the embodiment illustrated, rotational axis  141  is orthogonal to front-to-rear dimension  126 . As shown in  FIG. 3 , in one embodiment, a front portion of input gear  142  is exposed at the front  110  of housing  102  near the top  106  of housing  102  where input gear  142  engages the output gear in image forming device  22 . In the embodiment illustrated, a front portion of input gear  142  is exposed in a cutout  158  formed in a front portion of end cap  112 . With reference back to  FIG. 5 , in the embodiment illustrated, drive train  140  also includes a drive gear  144  on one end of drive shaft  134  that is connected to input gear  142  either directly or via one or more intermediate gears to rotate drive shaft  134 . In the embodiment illustrated, drive train  140  also includes a drive gear  146  on first end  132   a  of auger  132  that is connected to input gear  142  either directly or via one or more intermediate gears to rotate auger  132 . 
     With reference to  FIGS. 5-7 , toner cartridge  100  includes an encoded member  150  that is movably connected to drive train  140 , either directly or indirectly to input gear  142 . In the example embodiment illustrated, encoded member  150  includes a rotatable disk  152  operatively connected to drive train  140 , such as, for example, positioned on an outboard face  143  of input gear  142 , coaxially with input gear  142  as illustrated. Disk  152  may be formed integrally with input gear  142  or separately attached to input gear  142 . In other embodiments, encoded member  150  is, for example, translatable, such as by way of a rack and pinion arrangement or a cam and follower arrangement. Information pertaining to toner cartridge  100  is encoded on encoded member  150 . Encoded member  150  is detectable by sensor  300  in image forming device  22  when toner cartridge  100  is installed in image forming device  22  permitting sensor  300  to communicate the encoded information of toner cartridge  100  to controller  28  of image forming device  22  via communications link  57 . The encoded information may include, for example, authentication information such as a signature, serial number, or other identifier for authenticating or validating toner cartridge  100  upon installation of toner cartridge  100  in image forming device  22  or periodically during use of toner cartridge  100 . The encoded information may include, for example, characteristics of toner cartridge  100  such as toner color, initial toner fill amount, toner type, geographic region, manufacture location, manufacture date, etc. 
     In the example embodiment illustrated, authentication information is encoded on encoded member  150  by randomly distributed magnetized particles  154  dispersed on disk  152 , e.g., on the surface of disk  152  and/or within disk  152 . Particles  154  are distributed randomly such that it is difficult to reproduce the exact distribution and alignment of particles  154  thereby making the distribution difficult to copy. In this embodiment, sensor  300  is positioned in close proximity to encoded member  150  when toner cartridge  100  is installed in image forming device  22 , such as, adjacent to and facing the outboard side of disk  152  as schematically illustrated in  FIG. 7 . At predetermined times, such as upon the installation of a new toner cartridge in image forming device  22 , sensor  300  measures the magnetic field of disk  152  in one, two or three orthogonal dimensions as disk  152  rotates due to rotation of input gear  142  by motor  70 . The magnetic field values measured by sensor  300  are communicated to controller  28  via communications link  57 . Controller  28  may then compare the magnetic field values received from sensor  300  to values stored during manufacture in non-volatile memory of processing circuitry  45  of toner cartridge  100 . Controller  28  may confirm the authenticity of toner cartridge  100  to controller  28  if the magnetic field values received from sensor  300  match the values stored in non-volatile memory of processing circuitry  45 . 
     While the example embodiment illustrated includes information encoded by a random distribution of magnetized particles and detection by measuring the magnetic field of the particles, it will be appreciated that information may be encoded by a random distribution of non-magnetized particles and detection may occur according to other means, such as, for example, by measuring an optical property of the particles. Further, in lieu of a random pattern, information may be encoded according to a predetermined pattern using any suitable indicia and detection method. However, as discussed above, it is preferred for authentication information to be encoded according to a random pattern so that encoded authentication information is more difficult for a counterfeiter to reproduce. 
     With reference to  FIG. 6 , in the example embodiment illustrated, at least a portion of encoded member  150  is exposed on the exterior of toner cartridge  100 , e.g., above rotational axis  141  of input gear  142 , for reading by sensor  300 . For example, in the embodiment illustrated, encoded member  150  is exposed through a cutout  156  in end cap  112  that is positioned above rotational axis  141  of input gear  142 . Although it is preferred for at least a portion of encoded member  150  to be exposed for reading by sensor  300  in order to ensure an accurate reading of encoded member  150 , in other embodiments, encoded member  150  may be covered by a relatively thin material, e.g., in place of cutout  156 , so long as sensor  300  is still able to accurately read encoded member  150  through the material. 
       FIG. 8  shows drive train  140  in greater detail according to one example embodiment. In the example embodiment illustrated, input gear  142  is a compound gear that includes a first portion  142   a  that mates with the corresponding output gear in image forming device  22  when toner cartridge  100  is installed in image forming device  22  and a second portion  142   b  that meshes with drive gear  144  in order to provide rotational motion to drive shaft  134 . First portion  142   a  of input gear  142  also meshes with an idler gear  147  that, in turn, meshes with a compound idler gear  148 . Compound idler gear  148  includes a first portion  148   a  that meshes with idler gear  147  and a second portion  148   b  that meshes with drive gear  146  in order to provide rotational motion to auger  132 . It will be appreciated that the embodiment illustrated in  FIG. 8  is merely an example and that drive train  140  may take many suitable configurations for transferring rotational motion from input gear  142  to toner agitator assembly  130  and to encoded member  150 . 
     In some embodiments, in operation, controller  28  drives motor  70  in a first rotational direction to drive toner agitator assembly  130  and in a second rotational direction to perform a reading of encoded member  150  by sensor  300 . In particular, when controller  28  drives motor  70  in the first rotational direction, input gear  142  rotates in a first rotational direction  149   a  and, in turn, rotates auger  132  and drive shaft  134  in operative rotational directions  138 ,  139  to feed toner from toner cartridge  100  to developer unit  202 . When controller  28  drives motor  70  in the second rotational direction, input gear  142  rotates in a second rotational direction  149   b . Sensor  300  is configured to read encoded member  150  as input gear  142  rotates in rotational direction  149   b . In this manner, sensor  300  is able to perform a reading of encoded member  150  separately from a toner feed operation so that the authenticity or validity of toner cartridge  100  may be checked prior to the first use of toner cartridge  100  or at other times when toner cartridge  100  is not in use. 
     In some embodiments, toner agitator assembly  130  includes a one-way clutch that limits the rotational motion of at least one component of toner agitator assembly  130  to its operative rotational direction. For example, the one-way clutch may limit auger  132  and/or drive shaft  134  to its operative rotational direction  138 ,  139 . For example, the one-way clutch may be operatively connected to drive gear  144  such that when input gear  142  rotates in rotational direction  149   a , drive shaft  134  rotates in operative rotational direction  139  and when input gear  142  rotates in rotational direction  149   b , drive shaft  134  is decoupled and does not rotate with input gear  142 . In this manner, drive shaft  134  and toner agitators  136  do not rotate while sensor  300  performs a reading of encoded member  150 . As a result, torque on drive shaft  134  and toner agitators  136  from toner stored in reservoir  104  does not affect the movement of encoded member  150  thereby permitting better control of encoded member  150  while sensor  300  performs a reading of encoded member  150  and improving the accuracy of the reading performed by sensor  300 . Further, in some embodiments, toner agitators  136  may include flexible wipers that could displace or become damaged upon rotating counter to operative rotational direction  139 . Decoupling drive shaft  134  from input gear  142  when input gear  142  rotates in rotational direction  149   b  prevents this from occurring. 
     With reference back to  FIG. 6 , toner cartridge  100  includes a vertical alignment guide  160  positioned on side  108  of housing  102 , e.g., on an outer side of end cap  112 . In the embodiment illustrated, alignment guide  160  is positioned axially outboard of input gear  142  and encoded member  150  relative to rotational axis  141 . In this embodiment, alignment guide  160  is positioned below the portion of encoded member  150  exposed through cutout  156 . Alignment guide  160  is positioned to contact a housing of sensor  300  when toner cartridge  100  is installed in image forming device  22  and to position sensor  300  vertically relative to encoded member  150  as discussed in greater detail below. Alignment guide  160  includes a top surface  162  that is unobstructed (i.e., by any other portion of toner cartridge  100 ) to contact a housing of sensor  300  from below in order to lift sensor  300  upward during insertion of toner cartridge  100  into image forming device  22  and in order to support the housing of sensor  300  from below when toner cartridge  100  is in its final installed position in image forming device  22  to maintain vertical alignment of sensor  300  with encoded member  150  during operation as discussed in greater detail below. In the embodiment illustrated, alignment guide  160  is formed as an extension outward sideways from side  108  of housing, such as away from an outer side of end cap  112 . Top surface  162  includes a front portion  164  and a rear portion  166 . In the embodiment illustrated, front portion  164  and rear portion  166  combine to form a continuous top surface  162 . Front portion  164  of top surface  162  is positioned further forward (toward front  110  of housing  102 ) than rear portion  166  of top surface  162 . That is, front portion  164  of top surface  162  is positioned closer to front  110  of housing  102  than rear portion  166  of top surface  162  is to front  110  of housing  102 , and rear portion  166  of top surface  162  is positioned closer to rear  111  of housing  102  than front portion  164  of top surface  162  is to rear  111  of housing  102 . 
     Front portion  164  of top surface  162  of alignment guide  160  inclines upward and rearward, toward top  106  and rear  111 , such that front portion  164  of top surface  162  is positioned higher as it extends rearward toward rear  111  of housing  102 . Front portion  164  of top surface  162  may include a planar surface (including one or multiple planar facets) that inclines upward and rearward, a curved surface (e.g., a convex surface as viewed from above) that inclines upward and rearward, or a combination thereof. As discussed in greater detail below, during insertion of toner cartridge  100  into image forming device  22 , front portion  164  of top surface  162  contacts a housing of sensor  300  and lifts sensor  300  upward relative to toner cartridge  100  due to the incline of front portion  164  of top surface  162 . Front portion  164  of top surface  162  leads rearward to rear portion  166  of top surface  162 . In the embodiment illustrated, a portion of front portion  164  of top surface  162  extends lower than rear portion  166  of top surface  162 . 
     As discussed in greater detail below, rear portion  166  of top surface  162  of alignment guide  160  contacts a housing of sensor  300  and sets the final vertical position of sensor  300  relative to toner cartridge  100  when toner cartridge  100  is in its final installed position in image forming device  22  in order to align sensor  300  vertically with disc  152  of encoded member  150  during operation of toner cartridge  100 . In the example embodiment illustrated, rear portion  166  of top surface  162  is positioned higher than rotational axis  141  of input gear  142  and of disc  152 , and at least a portion of rear portion  166  of top surface  162  extends rearward (toward rear  111  of housing  102 ) of rotational axis  141  of input gear  142  and of disc  152 . However, rear portion  166  of top surface  162  may take other positions relative to rotational axis  141  depending on the location of the segment of encoded member  150  to be read by sensor  300 . 
     Rear portion  166  of top surface  162  overlaps with outboard face  143  of input gear  142 , including a portion of encoded member  150  on input gear  142  exposed through cutout  156 , as viewed from side  108  of housing  102  (i.e., as viewed in  FIG. 6 ) in order to permit sensor  300  to read encoded member  150  when a housing of sensor  300  is in contact with rear portion  166  of top surface  162 . In the embodiment illustrated, cutout  156  extends upward from rear portion  166  of top surface  162  such that a portion of encoded member  150  is exposed directly above rear portion  166  of top surface  162  for reading by sensor  300 . In the example embodiment illustrated, rear portion  166  of top surface  162  is positioned lower than a topmost portion of the gear teeth of input gear  142  and lower than at least a portion of the magnetized particles  154  on disc  152  of encoded member  150  in order to permit sensor  300  to read encoded member  150  when a housing of sensor  300  is in contact with rear portion  166  of top surface  162 . In the embodiment illustrated, rear portion  166  of top surface  162  is positioned immediately adjacent to encoded member  150 , e.g., spaced a few millimeters along an axial dimension of input gear  142  from encoded member  150 , in order to permit sensor  300  to be positioned in close proximity to encoded member  150  when toner cartridge  100  is installed in image forming device  22 . 
     In some embodiments, rear portion  166  of top surface  162  is formed by a planar portion of top surface  162 . In the example embodiment illustrated, rear portion  166  of top surface  162  is parallel to a bottom contact surface  125  of positioning guide  124  on side  108  of toner cartridge  100 . When toner cartridge  100  is installed in image forming device  22 , bottom contact surface  125  of positioning guide  124  contacts a top surface of a corresponding guide rail in image forming device  22  to define the vertical position of toner cartridge  100  relative to image forming device  22 . In the embodiment illustrated, bottom contact surface  125  of positioning guide  124  is defined by a pair of rounded bottom contact surfaces  125   a ,  125   b  that extend downward in a convex manner from the rest of positioning guide  124 . As shown in  FIG. 6 , an imaginary line  125   c  formed by the bottommost points of rounded bottom contact surfaces  125   a ,  125   b  of positioning guide  124  on side  108  of housing  102  is parallel to rear portion  166  of top surface  162  as depicted by imaginary line  168 . 
     In some embodiments, toner cartridge  100  also includes a rear stop  170  positioned on side  108  of housing  102 , e.g., on an outer side of end cap  112 . Stop  170  is positioned at a rear end of alignment guide  160 . Stop  170  includes a frontward facing surface  172  that faces toward front  110  of housing  102 . Frontward facing surface  172  may include, for example, a vertical or primarily vertical surface. Frontward facing surface  172  is unobstructed (i.e., by any other portion of toner cartridge  100 ) to contact the housing of sensor  300  in order to limit the position of sensor  300  in a direction from front  110  toward rear  111  along front-to-rear dimension  126  when toner cartridge  100  is in its final installed position in image forming device  22  in order to ensure that sensor  300  is aligned with encoded member  150  along front-to-rear dimension  126 . In the example embodiment illustrated, frontward facing surface  172  extends upward from a rear end of rear portion  166  of top surface  162  of alignment guide  160 , and frontward facing surface  172  is spaced rearward (toward rear  111  of housing  102 ) from rotational axis  141  of input gear  142  and of disc  152 . 
     With reference to  FIGS. 6 and 9 , in the example embodiment illustrated, toner cartridge  100  includes an axial alignment guide  180  positioned on side  108  of housing  102 , e.g., on an outer side of end cap  112 . As discussed in greater detail below, alignment guide  180  is positioned to contact a housing of sensor  300  during insertion of toner cartridge  100  into image forming device  22  and to move the housing of sensor  300  axially relative to rotational axis  141  in order to ensure that the housing of sensor  300  clears front edges of input gear  142  and disc  152  and to guide the housing of sensor  300  to cutout  156  for reading encoded member  150 . In the embodiment illustrated, alignment guide  180  is positioned directly in front of cutout  156 , closer to front  110  of housing  102  than cutout  156  is to front  110  of housing  102 . Alignment guide  180  leads rearward along side  108  of housing  102  toward the portion of encoded member  150  exposed through cutout  156 . 
     Alignment guide  180  includes a first guide surface  182  and a second guide surface  184  that is positioned rearward of first guide surface  182 . That is, first guide surface  182  is positioned closer to front  110  of housing  102  than second guide surface  184  is to front  110  of housing  102 , and second guide surface  184  is positioned closer to rear  111  of housing  102  than first guide surface  182  is to rear  111  of housing  102 . First guide surface  182  inclines outward sideways and rearward, away from side  108  of housing  102  and toward rear  111  of housing  102 , such that first guide surface  182  is positioned further outward sideways as it extends rearward toward rear  111  of housing  102 . First guide surface  182  may include a planar surface (including one or multiple planar facets) that inclines outward sideways and rearward, a curved surface that inclines outward sideways and rearward, or a combination thereof. Second guide surface  184  inclines inward sideways and rearward, toward reservoir  104  and opposite side  109  of housing  102  and toward rear  111  of housing  102 , such that second guide surface  184  is positioned further inward sideways as it extends rearward toward rear  111  of housing  102 . Second guide surface  184  may include a planar surface (including one or multiple planar facets) that inclines inward sideways and rearward, a curved surface that inclines inward sideways and rearward, or a combination thereof. 
     In the embodiment illustrated, a third guide surface  186  is positioned between first guide surface  182  and second guide surface  184  along front-to-rear dimension  126 . In this embodiment, first guide surface  182  leads rearward to third guide surface  186 , and third guide surface  186  leads rearward to second guide surface  184 . Third guide surface  186  has a substantially constant position along an axial dimension of rotational axis  141 . That is, in the embodiment illustrated, third guide surface  186  does not angle or incline inward sideways or outward sideways as it extends frontward or rearward. In other embodiments, first guide surface  182  leads directly to second guide surface  184  as desired. Guide surfaces  182 ,  184 ,  186  are unobstructed (i.e., by any other portion of toner cartridge  100 ) to contact the housing of sensor  300  during insertion of toner cartridge  100  into image forming device  22  and to move the housing of sensor  300  axially relative to rotational axis  141  during insertion of toner cartridge  100  into image forming device  22 . 
     In the embodiment illustrated, at least a portion of each of first, second and third guide surfaces  182 ,  184 ,  186  of alignment guide  180  is positioned higher than rotational axis  141  and higher than top surface  162  of vertical alignment guide  160 . In the embodiment illustrated, first and third guide surfaces  182 ,  186  are spaced forward, toward front  110  of housing  102 , from rotational axis  141 . In this manner, each of first and third guide surfaces  182 ,  186  is positioned closer to front  110  of housing  102  than rotational axis  141  is to front  110  of housing  102 . Further, at least a portion of second guide surface  184 , such as a point where second guide surface  184  begins to angle inward sideways and rearward, is spaced forward, toward front  110  of housing  102 , from rotational axis  141 , i.e., closer to front  110  of housing  102  than rotational axis  141  is to front  110  of housing  102 . The positioning of guide surfaces  182 ,  184 ,  186  allows alignment guide  180  to contact the housing of sensor  300  during insertion of toner cartridge  100  into image forming device  22  prior to sensor  300  reaching cutout  156  or encoded member  150  in order to ensure that the housing of sensor  300  clears front edges of input gear  142  and disc  152  and to guide the housing of sensor  300  to cutout  156  for reading encoded member  150 . 
     With reference to  FIG. 9 , in the embodiment illustrated, at least a portion of each of first and second guide surfaces  182 ,  184  extends further outward sideways from side  108  of housing  102  than input gear  142  and disc  152  of encoded member  150  extend from side  108  of housing  102  in order to ensure that the housing of sensor  300  clears front edges of input gear  142  and disc  152  during insertion of toner cartridge  100  into image forming device  22 . Third guide surface  186  is also positioned further outward sideways relative to side  108  of housing  102  than input gear  142  and disc  152  of encoded member  150  extend from side  108  of housing  102 . In the embodiment illustrated, disc  152  of encoded member  150  extends further outward sideways from side  108  of housing  102  than an innermost axial (relative to rotational axis  141 ) portion of each of first and second guide surfaces  182 ,  184  in order to permit the housing of sensor  300  to directly contact disc  152  of encoded member  150  when toner cartridge  100  is in its final installed position in image forming device  22  and sensor  300  is aligned with cutout  156 . 
     With reference to  FIGS. 10-12 , a sensor assembly  302  of image forming device  22  is shown according to one example embodiment. Sensor assembly  302  includes sensor  300  mounted to a sensor housing  304 . Sensor housing  304  is, in turn, mounted to a portion of a frame  306  of image forming device  22 . Frame  306  runs along front-to-rear dimension  126  of toner cartridge  100  when toner cartridge  100  is installed in image forming device  22 . Frame  306  is positioned in close proximity with and generally faces side  108  of toner cartridge  100  when toner cartridge  100  is installed in image forming device  22 . Frame  306  includes a guide slot  308  formed therein that receives positioning guide  124  on side  108  of toner cartridge  100  during insertion of toner cartridge  100  into image forming device  22 . Guide slot  308  is defined by a gap formed between a bottom guide rail  310  and a top guide rail  312 . A top surface  311  of bottom guide rail  310  contacts bottom contact surface  125  of positioning guide  124  on side  108  of toner cartridge  100  when toner cartridge  100  is installed in image forming device  22  to define the vertical position of toner cartridge  100  at side  108  relative to image forming device  22 . Guide slot  308  extends primarily along front-to-rear dimension  126  of toner cartridge  100 . A rear end  314  of guide slot  308  shown in  FIG. 10  is positioned proximate to rear  111  of toner cartridge  100  when toner cartridge  100  is installed in image forming device. 
     An output gear  316  is exposed on a portion of frame  306  above top guide rail  312  in the embodiment illustrated. Output gear  316  is operatively connected to motor  70  in image forming device  22  and mates with corresponding input gear  142  of toner cartridge  100  when toner cartridge  100  is installed in image forming device  22  in order to provide rotational motion to input gear  142 . 
     Frame  306  also includes a sensor mount  320  that is positioned above top guide rail  312  in the embodiment illustrated. Sensor housing  304  is mounted to sensor mount  320  of frame  306  in a manner that permits sensor housing  304  to move relative to frame  306 . Sensor mount  320  includes a top guide wall  322 , a bottom guide wall  323 , a front guide wall  324  and a rear guide wall  325  that aid in positioning sensor housing  304  vertically and along front-to-rear dimension  126  of toner cartridge  100  relative to frame  306 . Sensor mount  320  also includes an end wall  326  that aids in positioning sensor housing  304  axially relative to rotational axis  141  of toner cartridge  100  relative to frame  306 . 
     In the example embodiment illustrated, sensor  300  includes one or more hall-effect sensors  330  mounted on a printed circuit board  332 . Hall-effect sensor(s)  330  are configured to measure the magnetic field of magnetized particles  154  on disc  152  of encoded member  150  in one, two or three orthogonal dimensions as disc  152  rotates. Printed circuit board  332  facilitates communication of the magnetic field measurements obtained by hall-effect sensor(s)  330  to controller  28  of image forming device  22  by way of communications path  57 . Printed circuit board  332  having sensor  300  is fixedly mounted to sensor housing  304 . In the embodiment illustrated, a portion of sensor  300  is exposed through a cutout  334  on an outer face  336  of sensor housing  304  to permit an unobstructed reading of the magnetic field of magnetized particles  154  of encoded member  150  by sensor  300 . Outer face  336  of sensor housing  304  is positioned at an innermost end of sensor housing  304  along rotational axis  141  of toner cartridge  100  (nearest toner cartridge  100 ) and faces toward side  108  of toner cartridge  100 . 
     With reference to  FIG. 10 , sensor housing  304  includes a top  340 , a bottom  341 , a front side  342  and a rear side  343  that are positioned in close proximity to inside surfaces of top guide wall  322 , bottom guide wall  323 , front guide wall  324  and rear guide wall  325 , respectively. In the embodiment illustrated, sensor housing  304  and sensor mount  320  are sized to permit vertical movement of sensor housing  304  relative to sensor mount  320  of frame  306 . Upward movement of sensor housing  304  relative to frame  306  is limited by contact between top  340  of sensor housing  304  and top guide wall  322  of sensor mount  320 , and downward movement of sensor housing  304  relative to frame  306  is limited by contact between bottom  341  of sensor housing  304  and bottom guide wall  323  of sensor mount  320 . In the embodiment illustrated, sensor housing  304  and sensor mount  320  are sized to limit lateral movement along front-to-rear dimension  126  of toner cartridge  100  in comparison with the amount of vertical movement permitted. Forward lateral movement of sensor housing  304  along front-to-rear dimension  126  relative to frame  306  is limited by contact between front side  342  of sensor housing  304  and front guide wall  324  of sensor mount  320 , and rearward lateral movement of sensor housing  304  along front-to-rear dimension  126  relative to frame  306  is limited by contact between rear side  343  of sensor housing  304  and rear guide wall  325  of sensor mount  320 . 
     In the example embodiment illustrated, sensor housing  304  is biased by one or more springs downward and rearward along front-to-rear dimension  126 , i.e., toward bottom guide wall  323  and rear guide wall  325  of sensor mount  320 . In the embodiment illustrated, an extension spring  360  biases sensor housing  304  downward and rearward along front-to-rear dimension  126 . A first end  362  of extension spring  360  is anchored to top guide wall  322 , and a second end  363  of extension spring  360  is anchored to front guide wall  324 . A corner  344  of sensor housing  304  formed at an intersection of top  340  and front side  342  contacts a coil portion  364  of extension spring  360  that is intermediate ends  362 ,  363  and displaces coil portion  364  from its natural position along a straight line between ends  362 ,  363  causing coil portion  364  to bend around corner  344  of sensor housing  304 . The bending of coil portion  364  of extension spring  360  around corner  344  of sensor housing  304  causes coil portion  364  to remain in constant contact with corner  344  of sensor housing  304  and to apply a bias force on corner  344  of sensor housing  304  that urges sensor housing  304  downward and rearward as indicated by the arrow F 1  in  FIG. 10 . Corner  344  may include a chamfered surface  345  that provides a contact surface that is less likely to catch or snag on coil portion  364  of extension spring  360 . 
     With reference to  FIGS. 11 and 12 , in the embodiment illustrated, sensor housing  304  and sensor mount  320  are sized to permit axial movement of sensor housing  304  relative to sensor mount  320  of frame  306  along rotational axis  141  of toner cartridge  100 . In the embodiment illustrated, a vertical post  346  extends upward from top  340  of sensor housing  304 . Post  346  is received by an elongated slot  328  formed in top guide wall  322  of sensor mount  320 . Slot  328  is elongated axially relative to rotational axis  141  permitting post  346  to move axially within slot  328  relative to rotational axis  141 . Although not shown, in the example embodiment illustrated, bottom  341  of sensor housing  304  includes a post substantially identical to post  346  and bottom guide wall  323  of sensor mount  320  includes an elongated slot substantially identical to elongated slot  328 . The relationship between the posts of sensor housing  304  and the elongated slots of sensor mount  320  permit sensor housing  304  to move relative to frame  306  axially along rotational axis  141 , toward and away from side  108  of toner cartridge  100 . It will be appreciated that the post/slot interface of sensor housing  304  and sensor mount  320  may be reversed to instead include one or more guide posts on sensor mount  320  and one or more corresponding elongated guide slots in sensor housing  304  as desired to permit movement of sensor housing  304  relative to frame  306  axially along rotational axis  141  of toner cartridge  100 . 
     In the example embodiment illustrated, sensor housing  304  is biased by one or more springs outward from frame  306  (toward side  108  of toner cartridge  100 ) along rotational axis  141 , away from end wall  326  of sensor mount  320 . In the embodiment illustrated, a compression spring  370  biases sensor housing  304  outward from frame  306  (toward side  108  of toner cartridge  100 ) along rotational axis  141 . A first end  372  of compression spring  370  is positioned against end wall  326  of sensor mount  320 , and a second end  373  of compression spring  370  is positioned against a surface of sensor housing  304  and/or printed circuit board  332  that faces end wall  326 . Compression spring  370  applies a bias force on sensor housing  304  that urges sensor housing  304  outward from frame  306  (toward side  108  of toner cartridge  100 ) as indicated by the arrow F 2  in  FIG. 11 . The force applied by compression spring  370  urges the posts of sensor housing  304  toward the innermost ends (nearest toner cartridge  100 ) of the elongated slots of sensor mount  320  in the embodiment illustrated. 
     In the embodiment illustrated, sensor housing  304  includes first and second chamfered surfaces  348 ,  349  that facilitate smooth contact between sensor housing  304  and axial alignment guide  180  of toner cartridge  100  during insertion of toner cartridge  100  into image forming device  22  as discussed in greater detail below. First chamfered surface  348  is formed at an intersection of outer face  336  with front side  342  of sensor housing  304 . Second chamfered surface  349  is formed at an intersection of outer face  336  with rear side  343  of sensor housing  304 . In the embodiment illustrated, each chamfered surface  348 ,  349  is formed as a planar facet that is angled from outer face  336  toward the respective front side  342  and rear side  343  of sensor housing  304 . As desired, rounded surfaces may be used at the intersections of outer face  336  with front side  342  and rear side  343  of sensor housing  304  in place of the planar surfaces illustrated. 
       FIGS. 13-18B  sequentially illustrate the interaction between sensor housing  304  in image forming device  22  and the corresponding alignment guides on toner cartridge  100  during insertion of toner cartridge  100  into image forming device  22 .  FIG. 13  is a top plan view showing the position of toner cartridge  100  relative to frame  306  as toner cartridge  100  enters image forming device  22  when a front end of positioning guide  124  on side  108  of toner cartridge  100  enters guide slot  310  on frame  306 . Arrow  190  indicates the direction of insertion of toner cartridge  100  into image forming device  22  with front  110  of toner cartridge  100  leading.  FIG. 13  shows first guide surface  182  of axial alignment guide  180  of toner cartridge  100  approaching chamfered surface  349  of sensor housing  304  as toner cartridge  100  advances in direction of insertion  190 . Prior to contact between axial alignment guide  180  of toner cartridge  100  and sensor housing  304 , sensor housing  304  is fully extended outward along rotational axis  141 , toward side  108  of toner cartridge  100  as a result of the bias applied by compression spring  370  with post  346  of sensor housing  304  in contact with an innermost end  329   a  (nearest toner cartridge  100 ) of elongated slot  328 . 
       FIG. 14  is a top plan view showing the position of toner cartridge  100  relative to frame  306  with toner cartridge  100  advanced along direction of insertion  190  from the position shown in  FIG. 13 . As toner cartridge  100  advances further into image forming device  22  along direction of insertion  190 , first guide surface  182  of axial alignment guide  180  of toner cartridge  100  contacts chamfered surface  349  of sensor housing  304 . The force applied to chamfered surface  349  of sensor housing  304  by first guide surface  182  of axial alignment guide  180  as toner cartridge  100  advances overcomes the bias force applied to sensor housing  304  by compression spring  370  causing sensor housing  304  to retract along rotational axis  141 , toward frame  306  and away from side  108  of toner cartridge  100 , as a result of the angle of first guide surface  182 . When sensor housing  304  retracts, toward frame  306  and away from side  108  of toner cartridge  100 , post  346  of sensor housing  304  moves away from innermost end  329   a  of elongated slot  328  and toward outermost end  329   b  of elongated slot  328  as shown in  FIG. 14 . 
       FIGS. 15A and 15B  are a top plan view and a side elevation view, respectively, showing the position of toner cartridge  100  relative to frame  306  with toner cartridge  100  advanced along direction of insertion  190  from the position shown in  FIG. 14 .  FIG. 15B  shows the positions of sensor  300 , sensor housing  304  and sensor mount  320  relative to side  108  of toner cartridge  100  illustrated schematically in dashed line in order to avoid obscuring the features of toner cartridge  100 . As shown in  FIG. 15A , as toner cartridge  100  advances further into image forming device  22  along direction of insertion  190 , first guide surface  182  of axial alignment guide  180  of toner cartridge  100  clears and passes chamfered surface  349  of sensor housing  304 , and third guide surface  186  of axial alignment guide  180  of toner cartridge  100  contacts outer face  336  of sensor housing  304 . Contact between third guide surface  186  of axial alignment guide  180  and outer face  336  of sensor housing  304  maintains a substantially constant retracted axial position of sensor housing  304  relative to rotational axis  141  as toner cartridge  100  continues to advance as a result of the substantially constant position of third guide surface  186  along the axial dimension of rotational axis  141 .  FIG. 15B  shows front portion  164  of top surface  162  of vertical alignment guide  160  approaching bottom  341  of sensor housing  304 . Prior to contact between vertical alignment guide  160  of toner cartridge  100  and sensor housing  304 , sensor housing  304  is in its lowest vertical position as a result of the bias applied by extension spring  360  with bottom  341  of sensor housing  304  in contact with bottom guide wall  323  of sensor mount  320 . 
       FIGS. 16A and 16B  are a top plan view and a side elevation view, respectively, showing the position of toner cartridge  100  relative to frame  306  with toner cartridge  100  advanced along direction of insertion  190  from the position shown in  FIGS. 15A and 15B . As shown in  FIG. 16A , as toner cartridge  100  advances further into image forming device  22  along direction of insertion  190 , third guide surface  186  of axial alignment guide  180  of toner cartridge  100  maintains contact with and slides across outer face  336  of sensor housing  304  maintaining the retracted axial position of sensor housing  304  relative to rotational axis  141 . As shown in  FIG. 16B , as toner cartridge  100  advances further into image forming device  22  along direction of insertion  190 , front portion  164  of top surface  162  of vertical alignment guide  160  of toner cartridge  100  contacts bottom  341  of sensor housing  304 . The force applied to bottom  341  of sensor housing  304  by front portion  164  of top surface  162  of vertical alignment guide  160  as toner cartridge  100  advances overcomes the bias force applied to sensor housing  304  by extension spring  360  causing sensor housing  304  to lift upward as a result of the angle of front portion  164  of top surface  162 . When sensor housing  304  lifts upward, bottom  341  of sensor housing  304  lifts upward away from bottom guide wall  323  of sensor mount  320  as shown in  FIG. 16B . 
       FIGS. 17A and 17B  are a top plan view and a side elevation view, respectively, showing the position of toner cartridge  100  relative to frame  306  with toner cartridge  100  advanced along direction of insertion  190  from the position shown in  FIGS. 16A and 16B . As shown in  FIG. 17A , as toner cartridge  100  advances further into image forming device  22  along direction of insertion  190 , third guide surface  186  of axial alignment guide  180  of toner cartridge  100  clears and passes outer face  336  of sensor housing  304 , and second guide surface  184  of axial alignment guide  180  of toner cartridge  100  contacts chamfered surface  348  of sensor housing  304 . As toner cartridge  100  continues to advance along direction of insertion  190 , the bias force applied to sensor housing  304  by compression spring  370  causes sensor housing  304  to gradually extend along rotational axis  141 , away from frame  306  and toward side  108  of toner cartridge  100  as limited by contact between chamfered surface  348  of sensor housing  304  and second guide surface  184  of axial alignment guide  180  due to the angle of second guide surface  184 . When sensor housing  304  extends, away from frame  306  and toward side  108  of toner cartridge  100 , post  346  of sensor housing  304  moves back toward innermost end  329   a  of elongated slot  328  and away from outermost end  329   b  of elongated slot  328  as shown in  FIG. 17A . As shown in  FIG. 17B , as toner cartridge  100  advances further into image forming device  22  along direction of insertion  190 , rear portion  166  of top surface  162  of vertical alignment guide  160  of toner cartridge  100  contacts bottom  341  of sensor housing  304 . Contact between rear portion  166  of top surface  162  of vertical alignment guide  160  of toner cartridge  100  and bottom  341  of sensor housing  304  sets the final vertical position of sensor housing  304  relative to toner cartridge  100  in order to align sensor  300  vertically with the portion of disc  152  of encoded member  150  exposed in cutout  156  to be read by sensor  300 . 
       FIGS. 18A and 18B  are a top plan view and a side elevation view, respectively, showing the final position of toner cartridge  100  relative to frame  306  when toner cartridge  100  is in its final installed position in image forming device  22 . As shown in  FIG. 18A , as toner cartridge  100  advances further into image forming device  22  along direction of insertion  190  toward the final installed position of toner cartridge  100  in image forming device  22 , second guide surface  184  of axial alignment guide  180  of toner cartridge  100  clears chamfered surface  348  of sensor housing  304 , and sensor housing  304  reaches its final axial position along rotational axis  141  relative to toner cartridge  100  in order to set the axial distance from sensor  300  to disc  152  of encoded member  150 . In the example embodiment illustrated, contact between outer face  336  of sensor housing  304  and disc  152  sets the final axial position of sensor housing  304  relative to toner cartridge  100 . In other embodiments, contact between outer face  336  of sensor housing  304  and a portion of housing  102 , such as a portion of the outer side of end cap  112  positioned above cutout  156 , sets the final axial position of sensor housing  304  relative to toner cartridge  100 . As shown in  FIG. 18B , as toner cartridge  100  advances further into image forming device  22  along direction of insertion  190  toward the final installed position of toner cartridge  100  in image forming device  22 , rear portion  166  of top surface  162  of vertical alignment guide  160  of toner cartridge  100  maintains contact with and slides across bottom  341  of sensor housing  304  maintaining the final vertical position of sensor housing  304  relative to toner cartridge  100 . In the embodiment illustrated, forward facing surface  172  of rear stop  170  contacts rear side  343  of sensor housing  304  when toner cartridge  100  is in its final installed position in image forming device  22 , and contact between forward facing surface  172  of rear stop  170  and rear side  343  of sensor housing  304  sets the final position of sensor housing  304  relative to toner cartridge  100  along front-to-rear dimension  126  of toner cartridge  100  in order to align sensor  300  along front-to-rear dimension  126  with the portion of disc  152  of encoded member  150  to be read by sensor  300 . In other embodiments, because of the limited freedom of movement of sensor housing  304  relative to sensor mount  320  along front-to-rear dimension  126 , rear stop  170  may be omitted so long as precise alignment of toner cartridge  100  relative to image forming device  22  along front-to-rear dimension  126  is achieved. 
     While the example embodiment illustrated includes various alignment guides for engaging sensor  300  positioned on side  108  of toner cartridge  100 , near top  106  of toner cartridge  100 , it will be appreciated that the alignment guides of toner cartridge  100  that engage and position sensor  300  relative to toner cartridge  100  may be positioned in other suitable locations and orientations depending on the positions and orientations of encoded member  150  and sensor  300 . For example, in another embodiment, sensor housing  304  is biased upward instead of downward, and vertical alignment guide  160 , rear stop  170  and axial alignment guide  180  are flipped vertically relative to the embodiment shown in  FIG. 6  such that rear stop  170  and axial alignment guide  180  are positioned lower than vertical alignment guide  160 , and a portion of a bottom surface of vertical alignment guide  160  angles downward and rearward for contacting and moving sensor housing  304  downward against its bias during insertion of toner cartridge  100  into image forming device  22  with front  110  of housing  102  leading. The alignment guides of toner cartridge  100 , encoded member  150  and sensor  300  may take other suitable positions and orientations as desired. 
     Further, while the example embodiments discussed above include a toner agitator assembly  130  that includes a rotatable auger  132  and a rotatable drive shaft  134  having toner agitators  136  extending outward therefrom, it will be appreciated that toner agitator assembly  130  may include any suitable combination of rotating, shifting, reciprocating or otherwise movable toner agitators, which may take many shapes, forms, sizes and orientations. For example, the toner agitator(s) may include any suitable combination of one or more paddles, augers, rakes, combs, scoops, plows, arms, extensions, prongs, flaps, mixers, conveyors, screws, etc. 
     While the example embodiment shown in  FIG. 2  includes a pair of replaceable units in the form of toner cartridge  100  and imaging unit  200 , it will be appreciated that the replaceable unit(s) of image forming device  22  may employ any suitable configuration as desired. For example, in one embodiment, the main toner supply for image forming device  22 , developer unit  202  and cleaner unit  204  are housed in one replaceable unit. In another embodiment, the main toner supply for image forming device  22  and developer unit  202  are provided in a first replaceable unit (with the developer roll or magnetic roll of developer unit  202  forming the outlet of the first replaceable unit) and cleaner unit  204  is provided in a second replaceable unit. Further, while the example image forming device  22  discussed above includes one toner cartridge  100  and corresponding imaging unit  200 , in the case of an image forming device configured to print in color, separate replaceable units may be used for each toner color needed. For example, in one embodiment, the image forming device includes four toner cartridges and four corresponding imaging units, each toner cartridge containing a particular toner color (e.g., black, cyan, yellow or magenta) and each imaging unit corresponding with one of the toner cartridges to permit color printing. Further, while the example embodiments illustrated pertain to a toner agitator assembly  130 , an encoded member  150  and various alignment guides of a toner cartridge  100 , it will be appreciated that they may apply to a toner agitator assembly, an encoded member and alignment guides of any toner container including, for example, a developer unit, an imaging unit or a waste toner container. 
     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.