Abstract:
A toner cartridge with a uni-body construction reduces the cost of production as well as reducing the chance of failure during use. The toner cartridge includes a waste bin having a leading end that can be sculpted to mate with the cartridge-receiving cavities of a large number of printers. Additional improvements include an improved toner sifting agitator. The sifting action ensures that toner stays sufficiently fluid, and distributes evenly on the toner adder roller.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority to U.S. Provisional Patent Application No. 60/521,326, entitled, “Total Cartridge,” filed Apr. 1, 2004 and co-pending U.S. patent application Ser. No. 10/742,323 entitled “Removable Toner Cartridge Universal Adapter,” filed Dec. 19, 2003. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     Laser printers use a coherent beam of light, hence the term “laser printer,” to expose discrete portions of an image transfer drum thus attracting the printing toner. Toner is a mixture of pigment (most commonly black) and plastic particles. The toner becomes electrostatically attracted to exposed portions of the image transfer drum. The toner transfers to paper, or other medium, as it passes over the rotating image transfer drum. Subsequently, the paper is heated so that the plastic is melted thereby permanently affixing the ink to the paper.  
         [0003]     The vast majority of commercially available desktop laser printers include replaceable or removable toner cartridges that incorporate an image transfer drum, a toner tank, and a metering system. A drive mechanism connects to the drum and metering system. Modern toner cartridges often include a variety of sensors that interact with the laser printer to indicate the status of the cartridge. Indications relating to toner level, print quality and general cartridge function are often included as well. A large number of types and sizes of toner cartridges are currently available. The sensing system typically includes an encoder wheel interconnected with a rotating beater blade within a cylindrical toner tank. Movement of the beater blade feeds toner into the metering system. The encoder wheel reports the movement of the beater wheel through the rear housing.  
         [0004]     Previously, certain printers in the electro-photography industry have produced inconsistent images as a result of toner particles being unevenly distributed. What is therefore needed is a means of uniformly distributing toner as it leaves the hopper across the toner adder roller, thereby eliminating the clumping of toner particles.  
       SUMMARY OF INVENTION  
       [0005]     The long-standing but heretofore unfulfilled need for a toner cartridge that is adapted to be of an integrated construction, thereby limiting the number of elements required during manufacture, and which also includes improvements that overcome the limitations of prior art toner cartridges is now met by a new, useful, and non-obvious invention.  
         [0006]     The novel toner cartridge includes a waste bin at the leading end of the toner cartridge. A main body connects to the waste bin at a trailing end of the waste bin. The waste bin and main body fixedly interconnect to one another and are held against movement relative to one another when fully installed within said toner cartridge receiving cavity. A rear housing connects to the main body at the trailing end of the main body thereby defining a toner chamber therein. The rear housing and main body fixedly interconnect to one another and being held against movement relative to one another when manufactured. This construction creates a unibody cartridge with fewer connecting parts and no pivotal joints, which, as in the prior art, can fail.  
         [0007]     In an alternate embodiment, the waste bin includes a leading end sculpted to mate with the cartridge receiving cavity of a plurality of printers. The waste bin connects to the main body by fasteners chosen from the group consisting of adhesives, dovetail joinery, and mechanical fasteners.  
         [0008]     In another embodiment, the novel toner cartridge includes a toner cartridge adapted to fit within a toner cartridge-receiving cavity of a printer, comprising a main body, a toner chamber connected to the main body at the trailing end of the main body having an exit surface to deliver toner from the toner chamber, and a sifting agitator having a first end and a second end extending across the exit surface capable of lateral movement across the exit surface. The novel toner cartridge further comprises a cam gear having a high surface and a low surface disposed at a first end of the sifting agitator such that rotation of the cam gear alternately engages and disengages the first end of the sifting agitator as the cam gear rotates. A resilient member mounts to one end of the sifting agitator for exerting force on the agitator to return the agitator to a home position. The resilient member is mounted on the sifting agitator and has a portion engaging the interior of the toner chamber.  
         [0009]     The sifting agitator includes a plurality of lower chamber contouring fins spaced along the longitudinal axis of the sifting agitator adapted to move in lateral relation to the toner adder roller. A plurality of upper fins spaced along the longitudinal axis of the sifting agitator are adapted to contour the toner chamber. A cam pin disposed at the first end of the sifting agitator to engages the high surface of the cam gear as it rotates urging the sifting agitator to move laterally away from the cam gear. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, in which:  
         [0011]      FIG. 1  is a perspective view of the novel toner cartridge;  
         [0012]      FIG. 2  is an exploded perspective view of the novel toner cartridge;  
         [0013]      FIG. 3  is an exploded perspective view of the novel toner cartridge;  
         [0014]      FIG. 4  is a top perspective view of the novel toner cartridge showing one means of fastening the waste bin to the main body;  
         [0015]      FIG. 4A  is a close-up top perspective view of the vent apparatus disposed within the main body;  
         [0016]      FIG. 5  is an exploded perspective view of the novel toner cartridge showing an alternate means of fastening the waste bin to the main body;  
         [0017]      FIG. 6  is a side cross-section view of the main body of the novel toner cartridge;  
         [0018]      FIG. 7  is a rear perspective view of the main body of the novel toner cartridge showing the first embodiment of the sifting agitator;  
         [0019]      FIG. 7A  is a front perspective view of the main body of the novel toner cartridge;  
         [0020]      FIG. 8  is an exploded perspective view of the first embodiment of the sifting agitator;  
         [0021]      FIG. 9  is an exploded perspective view of the inter-relation of the sifting agitator, conforming seals, toner adder roller, and gear plate;  
         [0022]      FIG. 10  is a perspective view of the inter-relation of the sifting agitator, conforming seals, toner adder roller, gear plate, developer roller, and gear train;  
         [0023]      FIG. 11  is an alternate perspective view of the inter-relation of the sifting agitator, conforming seals, toner adder roller, gear plate, developer roller and gear train;  
         [0024]      FIG. 12  is an exploded perspective view of the inter-relation of the sifting agitator, conforming seals, toner adder roller, gear plate, developer roller and gear train;  
         [0025]      FIG. 13  is a side perspective view of the cam gear;  
         [0026]      FIG. 14  is a side perspective view of the gear plate;  
         [0027]      FIG. 14A  is a side perspective view of the gear plate;  
         [0028]      FIG. 15  is a front perspective view of the rear housing and oval plug of the novel toner cartridge;  
         [0029]      FIG. 16  is a perspective view of an alternative construction configuration of the novel toner cartridge. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0030]     In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part hereof, and within which are shown by way of illustration specific embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention.  
         [0031]     In a general embodiment the novel toner cartridge has a photoconductive drum on which an electrostatic image is formed. The photoconductive drum rotates in a plane perpendicular to that of the print medium passing through the toner cartridge. A recovery blade is in direct contact with the photoconductive drum. During the imaging stage, the photoconductive drum is exposed to light, usually a laser, which imprints a latent image thereon. A developing roller converts the electrostatic-image into a toner-image. Toner is then transferred to the print medium by means of static electricity, an opposite polar charge on the print medium, established by a transfer roller. The recovery blade then scrapes the waste toner from the photoconductive drum and directs it to the waste bin.  
         [0032]     Construction of the Novel Toner Cartridge  
         [0033]     Referring now to  FIGS. 1 and 2 , it will be seen that the reference numeral  1  denotes an illustrative embodiment of the novel toner cartridge as a whole. Novel toner cartridge  1  is made by interconnecting waste bin  10  and rear housing  40  to main body  20 . Specifically, as suggested by the alignment of parts in  FIG. 3 , trailing end of waste bin  10  connects to the leading end of main body  20 . In similar fashion, the leading end of rear housing  40  connects to the trailing end of main body  20  ( FIG. 2 ).  FIGS. 4 and 5  illustrate possible methods of connecting waste bin  10  with main body  20 . In one embodiment ( FIG. 3 ) waste bin  10  is positioned over the leading end of main body  20  and then lowered until the two parts are interconnected via correlating connecting mechanisms  11  located on waste bin  10  and the leading end of main body  21 . Illustrative embodiments of how waste bin  10  connects to main body  20  are disclosed more fully herein.  
         [0034]     Waste Bin: The waste bin is attached to the main body either permanently or by releasable means, for the purposes of maintenance. When employing mechanical fasteners, the fasteners ( FIG. 4 ), are located in predetermined locations such as by way of precisely positioned screw-bosses  12  located on waste bin  10 , that mate with holes  22  formed in receiving tabs on main body  20 . An alternative attachment method,  FIG. 5 , is achieved by means of an integral fastener received by a flared receiving channel  12   a , much like a dove-tail joint, on waste bin  10  that accepts a pin  22   a , on main body  20  by way of a sliding action whereby the pin and channel interlock. The wiper blade and the recovery blade are integrated with the front section.  
         [0035]     Main Body:  FIG. 6  shows the construction of main body  20  independent of waste bin  10  and rear housing  40 . Main body  20  houses the doctor bar &amp; spring, developer roller, toner adder roller, photoconductive drum, sealing members and a toner sifter (not shown). At its leading end, main body  20  has two extensions  21  at its lateral ends adapted to receive waste bin  10  (as discussed supra). Doctor bar &amp; spring, developer roller, toner adder roller, photoconductive drum, sealing members and a toner sifter (not shown) are located between extensions  21  and in trailing relation to waste bin  10 .  
         [0036]     As depicted in  FIG. 7 , the trailing end of main body  20  is open, defining a space between the lateral walls thereof. On one end of main body  20  the side wall extends outward to form a male-connection point  25 , received by rear housing  40 , as discussed below. An opening  25   a  is disposed within male-connection point  25  through which extends the primary shaft of the beater/measuring device (discussed below) to communicate with the gear which drives the toner beater measuring device.  
         [0037]     The adjacent side wall is adapted with a semi-circular inward recess defining a female-connection point  26  to receive a corresponding male-connection point on rear housing  40 . Protective cover  27  is disposed adjacent to the side wall comprising female-connection point  26  to prevent external forces, while in use or in storage, from causing damage to the moving parts of the toner cartridge. Protective cover  27  also provides a contact point for a pin located on the encoder disk of the beater mechanism, opposite the gear which drives the rotation thereof. This contact point prevents lateral movement of the encoder disk during operation.  
         [0038]     Main body  20  is equipped with vent  24  (see  FIGS. 4 and 4 A). Vent  24  permits air to enter the toner chamber as toner leaves the toner chamber, thus facilitating the flow of toner. Without vent  24 , a vacuum builds within the toner cartridge and the resulting nternal pressure would prevent the out-flow of toner. A filtration material, such as felt, fits over vent  24  to prevent toner from escaping through vent  24 . The filter material must be sufficiently permeable to allow air to pass into the toner chamber, while sufficiently impermeable to prevent the escape of toner. Air channels  24   a  allow air to flow to vent  24  when a circuit board or retaining material is placed over circuit board-receptacle  24   b.    
         [0039]     Referring again to  FIG. 7 , lower wall  30  of the toner chamber terminates at a point substantially above the bottom surface of the toner chamber. Lower wall  30  terminates as flat surface  31  ( FIG. 7A ). The exit surface of the toner extends from flat surface  31  downwardly toward the toner adder roller (not shown).  
         [0040]     Sifting agitator  100  extends across flat surface  31  ( FIG. 7A ). Turning now to  FIG. 8 , sifting agitator  100  comprises shaft  105 , upper fins  110 , lower chamber contouring fins  115 , cam pin  120 , axle  125 , biasing spring  130 , and pin  135 . In a general embodiment, sifting agitator  100  oscillates across flat surface  31  during printer operations. Toner spreads evenly across the exit surface of the toner cartridge as lower chamber contouring fins  115  sift the exiting toner.  FIGS. 9 and 10  show how lower chamber contouring fins  115  curve to fit toner adder roller  140  to ensure the closeness of sifting agitator  100  to toner adder roller  140 . In so doing, toner disperses evenly across the exit surface immediately prior to contact with toner adder roller  140 . The sifting agitator doesn&#39;t contact the adder roller but closely contours the lower surface of the toner chamber and the adder roller, thus assuring the toner stays sufficiently fluid and level near the adder roller.  
         [0041]     Conforming seals  127  and  129  are disposed at the end of sifting agitator  100  to engage gear plate  160  and prevent the escape of toner from the sides of the cartridge. Similarly, conforming seals  143 ,  145  are placed on either end of toner adder roller  140 .  
         [0042]      FIG. 11  shows how toner sifter  100  oscillates across flat surface  31 . In  FIG. 11 , drive dog gear  95  engages the drive apparatus of the printer (not shown). Rotation of drive dog gear  95  provides the rotational force for all gears in the gear train shown in  FIG. 11 . Rotation of cam gear  150  applies lateral force on sifting agitator  100  by means of a beveled inner surface which engages and disengages pin  120  ( FIG. 12 ).  
         [0043]     Lateral movement of sifting agitator  100  away from the gear train causes biasing spring  130  to compress. When cam gear  150  disengages pin  120 , biasing spring  130  expands returning sifting agitator to its home position. Spring biasing means  130  mounts on sifting agitator and engages the interior of the toner chamber by means of pin  135 . Thereby, after sifting agitator  100  is moved from its home position by cam gear  150 , the potential energy stored in biasing spring  130  is exerted against sifting agitator  100  to return it to its home position. In addition to the biasing spring shown in  FIGS. 8-11 , any resilient means for exerting the necessary force on sifting agitator  100  to return it to its home position are contemplated.  
         [0044]      FIG. 12  shows an exploded view of the connection between sifting agitator  100  and cam gear  150  through gear plate  160 . As it can be seen, shaft  105  of the sifting apparatus terminates in axle  125  which includes cam pin  120 . Conforming seal  127  rests on the outer circumferential edge of axle  125  and mates with conforming seal  129 . Conforming seal  129  correspondingly rests on ridge  165  of gear plate  160 . When fully assembled, cam pin  120  extends through gear plate  160 . The inner surface of cam gear  150  is beveled and has a high surface  155  and low surface  153 . Cam gear  150  rotates on cam axle  163  of gear plate  160 . As cam gear  150  rotates, cam pin  120  is alternatively engaged by high surface  155  and disengaged by low surface  153 . When high surface  155  engages cam pin  120  sifting agitator  100  is urged laterally away from gear plate  160 . When low surface  153  rotates to a position adjacent to cam pin  120  the potential energy stored in biasing spring  130  urges sifting agitator  100  to return to its home position. The continued rotation of cam gear  150 , and the coincident revolution of high surface  155 , coupled with the resiliency of biasing spring  130  thereby create the oscillating movement of sifting agitator  100 . Cam gear  150  is shown in greater detail in  FIG. 13 .  
         [0045]     The outer surface of gear plate  160  is shown in  FIG. 14 . As mentioned above, cam gear  150  (not shown) rests and rotates upon cam gear axle  163 . Cam gear pin  120  protrudes through gear plate  160  through aperture  167 . Cam gear axle  163  is in displanar relationship to aperture  167  to ensure that high surface  155  and low surface  153  alternately engage and disengage cam pin  120  as cam gear  150  rotates.  FIG. 14A  provides a view of the reverse side of gear pate  160 .  
         [0046]     Toner Chamber: As shown in  FIG. 15 , the leading edge of rear housing  40  has a perimeter of a connecting surface  48  in the fashion of a tongue-and-groove, to mate with a corresponding connecting surface  28  of main body  20  ( FIG. 7 ). Rear housing  40  includes vertical tabs  49  formed on its upper surface that engage slots  29  formed on main body  20  ( FIG. 7 ). Rear housing  40  can be adhered to main body  20  by any means known in the art. Illustrative examples include, but are not limited to, adhesives, welding, and mechanical fasteners.  
         [0047]     When rear housing  40  mates with main body  20 , a toner chamber is defined by the cavity formed therein. Toner is discharged from a lower portion of main body  20  and supplied to the toner-adder roller. The toner chamber holds fresh, unused toner and houses the beater and measuring bar. The toner beater and measuring bar extend from the primary drive shaft. The primary drive shaft is rotatably supported and driven, through a gear train, by a drive element in the laser printer. The toner beater and measuring bar agitate the toner, thus preventing the toner from becoming compacted. In this manner, the toner is kept sufficiently fluid to be discharged uniformly from main body  20 .  
         [0048]     Fill-hole  45  is disposed within the side wall of rear housing  40  ( FIG. 15 ). Fill-hole  45  is preferably oval shaped, thus allowing air to escape the toner chamber as toner is funneled into the toner chamber. Fill-cap  45   a  is inserted into fill-hole  45  so toner cannot escape there through. In one embodiment fill-cap  45   a  is releasably placed within fill-hole  45  so the cartridge can be recycled and re-filled.  
         [0049]     Alternatively, the novel toner cartridge can be manufactured using two halves which are adhered together. For example,  FIG. 16  shows an alternate construction method of toner cartridge  1  wherein top portion  1   a  is adhered to bottom portion  1   b . It is also contemplated that similar construction can be achieved using a left and right portion adhered along their longitudinal access. This construction also permits the addition of the elements necessary for operation (photoconductive drum, beater, toner adder roller, etc.).  
         [0050]     It will be seen that the objects set forth above, and those made apparent from the foregoing description, are efficiently attained and since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matters contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.  
         [0051]     It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween. Now that the invention has been described.