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 beater and sensing apparatus, the elimination of a pivotal motion between the elements of the cartridge, an enhanced method of determining the amount of toner remaining in the toner chamber, and an improved means of agitating the toner within the toner chamber.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   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 which are fully incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   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 electro-statically attracted to exposed portions of the image transfer drum. The toner is transferred 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. 
   The vast majority of commercially available desktop laser printers include replaceable or removeable toner cartridges that incorporate an image transfer drum, a toner tank, and a metering system. A drive mechanism is connected 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 agitating paddle within a cylindrical toner tank. Movement of the agitating paddle feeds toner into the metering system. The encoder wheel reports the movement of the agitating paddle wheel through the toner reservoir. 
   Previously, certain printers in the electro-photography industry have only been able to receive a toner cartridge consisting of two assemblies, a hopper and a waste bin. This dual assembly requires that the respective parts be held together with an attaching bias, such as springs. The attaching bias may fail, rendering the cartridge apparatus inoperable. Therefore, what is needed is a complete, or uni-body, and non-removable toner cartridge that integrates the hopper and the waste bin into a single unit, thereby eliminating the potential of failure inherit in the printers of the prior art. 
   SUMMARY OF INVENTION 
   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. 
   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 are fixedly interconnected 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 are fixedly interconnected 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. 
   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. 
   In another embodiment, the novel toner cartridge includes a toner beater and sensing device for use in a toner cartridge having a toner chamber including a primary shaft rotatable in the toner chamber having a plurality of support members protruding radially from the primary shaft. A sensing device pivotally connects to the primary shaft such that the sensing device rotates within the toner chamber in the same path of travel as, and in leading relation to, the support members. An encoder disk connects to one end of the primary shaft connected to the sensing device, such that the rotation of the sensing device coincides with the rotation of the encoder disk. A gear is disposed at one end of the primary shaft such that rotation of the gear causes the primary shaft to rotate within the toner chamber. 
   The toner beater and sensing device include a biasing means attached to the encoder disk and primary shaft such that the sensing device is selectively forced, when no resistance is exerted upon thereon, into leading relation to the support members as the primary shaft rotates. Adjacent to the gear, the toner beater and sensing device includes a spiral support material disposed along one of the primary shaft adjacent to the gear such that toner is urged from the perimeter of the toner chamber toward the center of the chamber. 
   In alternate embodiments, encoder disk further includes a plurality of indicia capable of detection by a printer such that detection thereof indicates the level of toner in the toner chamber. The encoder disk further includes a plurality of blades across its outer surface such that rotation of the encoder disk causes particulate matter to be blown away from the encoder disk thus cleaning the light sensor in the printer. 
   In one embodiment, the gear connected to the primary shaft is a ratcheting gear. In a general embodiment, the ratcheting gear includes a plurality of ratcheting detents radially oriented within the inner surface of the ratcheting gear. A gear disk is rotatably disposed within the ratcheting gear, equipped with a plurality of pawls adapted to be received by the detents of the ratcheting gear such that the ratcheting gear will rotate about the gear disk when the resistance on the primary shaft exceeds the force applied by the rotation of the ratcheting gear. 
   Also provided is a method of sensing the amount of toner in a toner cartridge having a toner chamber by providing a primary shaft that plurality of support members that protruding radially from the primary shaft. A sensing device is pivotally connected to the primary shaft such that the sensing device rotates within the toner chamber in the same path of travel as, and in leading relation to, the support members. An encoder disk disposed at one end of the primary shaft connected to the sensing device, such that the rotation of the sensing device is conjoint with the rotation of the encoder disk. As the mechanism rotates through the toner chamber, the sensing device comes into contact with the toner where it stops until support structures of primary driving shaft engage it and drive it through the toner. When the toner sensing device emerges from the body of toner it springs forward and the cycle begins again. A number of indicia established on the encoder disk are detected by a light source within the printer. A toner usage algorithm is defined based on the position of the indicia on the encoder disk, as detected by the light source within the printer, when the sensing device contacts the toner. The amount of toner estimated to be remaining within the toner chamber is communicated to the user by the interface provided by the printer software. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     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: 
       FIG. 1  is a perspective view of the novel toner cartridge; 
       FIG. 2  is an exploded perspective view of the novel toner cartridge; 
       FIG. 3  is an exploded perspective view of the novel toner cartridge; 
       FIG. 4  is a top perspective view of the novel toner cartridge showing one means of fastening the waste bin to the main body; 
       FIG. 4A  is a close-up top perspective view of the vent apparatus disposed within the main body; 
       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; 
       FIG. 6  is a side elevational view of the main body of the novel toner cartridge; 
       FIG. 7  is a rear perspective view of the main body of the novel toner cartridge; 
       FIG. 8  is a front perspective view of the rear housing and oval plug of the novel toner cartridge; 
       FIG. 9  is a perspective view of an alternative construction configuration of the novel toner cartridge. 
       FIG. 10  is a perspective view of the toner beater and sensing device of the novel toner cartridge; 
       FIG. 11  is an exploded perspective view of he toner beater and sensing device of the novel toner cartridge; 
       FIG. 12  is an exploded perspective view of the encoder disk and biasing means; 
       FIG. 13  is an exploded perspective view of the encoder disk and primary shaft; 
       FIG. 14  is an exploded perspective view of the ratcheting gear; 
       FIG. 15  is an exploded perspective view of the ratcheting gear; 
       FIG. 16  is a perspective view of the assembled ratcheting gear; 
       FIG. 17  is a side elevational view of the gear train of the novel toner cartridge showing; 
       FIG. 18A  is a perspective view of the operation of the sensing device and toner agitating mechanism wherein the sensing device has contacted the toner in leading relation to the support members; 
       FIG. 18B  is a perspective view of the operation of the sensing device and toner agitating mechanism wherein the sensing device has stopped in contact with the toner and the support members have continued their rotation; 
       FIG. 18C  is a perspective view of the operation of the sensing device and toner agitating mechanism wherein the support members have engaged the sensing device; 
       FIG. 18D  is a perspective view of the operation of the sensing device and toner agitating mechanism wherein the support members have begun to drive the sensing device through the toner, thus agitating the toner; 
       FIG. 18E  is a perspective view of the operation of the sensing device and toner agitating mechanism wherein the sensing device has left the toner and sprung forward in leading relation to the support members. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   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. 
   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 placed 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. 
   Construction of the Novel Toner Cartridge 
   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  30  to main body  20 . Specifically, as suggested by the alignment of parts in  FIG. 3 , trailing end of waste bin  10  is connected to the leading end of main body  20 . In similar fashion, the leading end of toner reservoir  30  is connected 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  is connected to main body  20  are disclosed more fully herein. 
   Waste Bin: The waste bin is attached to the main body either permanently or by releasable means, for the purposes of maintenance. When mechanical fasteners are employed, 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. 
   Main Body:  FIG. 6  shows the construction of main body  20  independent of waste bin  10  and rear housing  30 . 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 . 
   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  which is received by rear housing  30 , as discussed below. An opening  25   a  is disposed within male-connection point  25  through which extends the primary shaft of the beater/sensing device (discussed below) to communicate with the gear which drives the toner beater sensing device. 
   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  30 . 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 ( 73 ,  FIG. 13 ) located on the encoder disk, opposite the gear which drives the rotation thereof. This contact point prevents lateral movement of the encoder disk during operation. 
   Main body  20  is equipped with vent  24  (see  FIG. 4 ). Vent  24  permits air to enter the toner chamber as toner is expelled, thus facilitating the flow of toner. Without vent  24 , a vacuum would be created within the toner cartridge and the resulting external pressure would prevent toner from being applied. A filtration material, such as felt, is placed 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.    
   Toner chamber: As shown in  FIG. 8 , the leading edge of rear housing  30  has a perimeter of a connecting surface  38  in the fashion of a tongue-and-groove, to mate with a corresponding connecting surface  28  of main body  20  ( FIG. 7 ). Rear housing  30  includes vertical tabs  39  formed on its upper surface that engage slots  29  formed on main body  20  ( FIG. 7 ). Rear housing  30  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. 
   When rear housing  30  is mated 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 sensing device. The toner beater and sensing device 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 sensing device 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 . 
   Fill-hole  35  is disposed within the side wall of rear housing  30  ( FIG. 8 ). Fill-hole  35  is preferably oval shaped, thus allowing air to escape the toner chamber as toner is funneled into the toner chamber. Fill-cap  35   a  is inserted into fill-hole  35  so toner cannot escape there through. In one embodiment fill-cap  35   a  is releasably placed within fill-hole  35  so the cartridge can be recycled and re-filled. 
   Alternatively, the novel toner cartridge can be manufactured using two halves which are adhered together. For example,  FIG. 9  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.). 
   Beater and Sensing Device 
   One embodiment of the inventive apparatus includes a shaft assembly, denoted as whole by reference numeral  40  in  FIG. 10 , comprising, generally, a primary drive shaft  50 , having a cored-out region  52  ( FIG. 11 ) which provides a point of connection for a toner sensing device  60 . Primary shaft  50  further comprises a plurality of protruding support-members  55 , spiraling support material  56  and axle  57  upon which is mounted gear  80  for conjoint rotation therewith ( FIG. 11 ). 
   Toner sensing device  60  is pivotally connected to primary drive shaft  50 . The range of motion of sensing device  60  is between zero (0) degrees (direct contact) and an angle not to exceed one hundred eighty (180) degrees with respect to protruding support members  55  affixed to primary shaft  50  (see  FIG. 18 ). When sensing device  60  is oriented at zero (0) degrees, with relation to support members  55 , it is in its position of engagement. When sensing device  60  is oriented at its greatest distance from support members  55 , it is in its position of repose. 
   In one embodiment, toner sensing device  60  comprises a sensing device shaft  63  which resides within a cored out region  52  of primary shaft  50 . In this embodiment, sensing device  60  is spaced away from primary shaft  50  by extension arms  65 . In this manner sensing device  60  moves in an arcuate path of travel in relation to both primary shaft  50  and sensing device shaft  63 . The range of motion of sensing device  60  is between zero (0) degrees (engagement) and an angle not to exceed one hundred eighty (180) degrees with respect to protruding support members  55  affixed to primary shaft  50  (repose) (see  FIG. 18 ). 
   Opposite of gear axle  57 , primary shaft  50  is hollow  52   a  to enable insertion of encoder axle  70  into primary shaft  50  at hollow end  52   a  and thereby extend into cored-out region  52 . Encoder axle  70  thereby engages sensing device shaft  63  causing sensing device  60  to rotate as force is exerted on encoder axle  70 . Accordingly, encoder axle  70 , and therefore sensing device shaft  63 , rotate independently of primary shaft  50  when the disposition of sensing device  60  is between zero (0) degrees (direct contact) and an angle not to exceed one hundred eighty (180) degrees with respect to protruding support members  55  affixed to primary shaft  50  (see  FIG. 11 ). 
   Biasing means  72 , such as a spring, engages encoder disk  75  and primary shaft  50 , preferably at a point along shaft  50  which is outside the body of the completed cartridge, such as point  72   a . Biasing means  72  applies sufficient rotational force to encoder axle  70  (and thereby on sensing device shaft  63 ) to extend sensing device  60  to its point of repose, not greater than one hundred eighty (180) degrees from protruding support members  55  when no resistance, i.e. no toner, is exerted against sensing device  60 . 
   Accordingly, gear  80  provides the rotational force for primary shaft  50  at all times and for toner sensing device  60  when toner sensing device  60  is at its point of repose, or its minimal distance, engagement. Biasing means  72  provides rotational force for sensing device  60  when sensing device  60  is between its minimum and maximum extension range. 
   Conforming seals are used to prevent toner from leaking from the toner chamber. Two seals  63   a ,  63   b  are placed on the ends of sensing device shaft  63  at its distal ends. Conforming seal  63   a  is disposed at the distal end of sensing device shaft  63  where it abuts inner surface of cored-out region  52 . In this manner, toner is prevented from traveling through the hollow section  52   a  of primary shaft  50  and out of the toner chamber. Seal  63   b  prevents toner from infiltrating the contact space between sensing device shaft  63  and cored-out region  52  opposite encoder axle  70 , which could cause binding of sensing device shaft  63  thus interfering with its pivoting action. Conforming seals  50   a  and  50   b  insulate the distal ends of primary shaft  50  to prevent toner from escaping the chamber. 
     FIG. 12  shows a detail construction of encoder disk  75  in one embodiment of the inventive apparatus. Biasing means  72  connects to encoder wheel  75  at point  72   b . The opposite end of biasing means  72  attaches to primary shaft  50  at point  72   a  as discussed supra. The end of encoder axle  70  is provided with a contact surface  71  which engages sensing device shaft  63 . In this manner, the force exerted on encoder axle  70  by biasing means  72  transfers to sensing device shaft  63  causing it to rotate if the force exceeds the resistance. 
   Toner level indicia  78  can be disposed along any radius of encoder disk  75 . In operation a detecting source, usually a beam of light, is projected against encoding disk  75 . When the disk rotates so as to expose indicia  78  to the beam, the light passes through encoding disk  75  to a sensor which tells the printer the level of toner. Window  79  is disposed within encoder disk  75  to serve as a reference point for the toner level sensor of the printer. Any number of indicia can be used, as will be appreciated by one skilled in the art. 
   When the printer starts its initialization sequence, a light sensitive sensor in the printer identifies the position of window  79  and relays a signal to the intelligence in the host printer which references the position of the window as the home position. The home position is necessary for the printer to complete the initialization sequence. An error signal is generated when the home position cannot be determined, thus disabling operation of the printer. 
     FIG. 13  offers an alternative view of how encoder axle  70  fits within the hollow end  52   a  of primary shaft  50 . Contact surface  71  extends to sensing device shaft  33 , after passing through the hollow end  52   a  of primary shaft  50 .  FIG. 13  also depicts the outer surface of encoder disk  75 , which contains a series of blades  77 . As sensing device  60  is released from resistance (usually provided by the presence of toner), it springs forward due to the rotational force provided by biasing means  72 . The increased rotation of encoder disk  75  causes blades  77  to channel air in a fan-like motion. The fan-like action of encoder disk  75  helps to “blow-clean” any toner or other particulate matter from the toner sensing mechanism. 
   Gear  80  provides the rotational force for primary shaft  50 . Gear  80  engages the gear train of the toner cartridge (See  FIG. 17 ) which connects to the drive means of the printer through drive dog gear  90 . When a toner cartridge remains idle for a long period of time, as with storage, the toner inside can settle and become compacted. Accordingly, when the beater mechanism contacts the compacted toner, the shaft may stop when the drive gear does not. The drive gear can shear off the connecting end of primary shaft  50  causing catastrophic failure. 
   In one embodiment, the beater assembly uses a ratcheting gear mechanism  80  ( FIGS. 14–16 ), although a rigid gear drive is envisioned as well. The ratcheting gear assembly includes a ratcheting drive gear  80  with detent notches  82 . Gear disk  85  bearing ratcheting pawls  88  is disposed within gear  80 . When beater  40  contacts the compacted toner, ratcheting pawls  88  slip in ratcheting detents  82  of ratcheting gear  80 . This prevents the shearing of the shaft experienced in the prior art. Every time gear disk  85  slips and engages gear  80 , it drives the beater assembly through the toner slightly, as with a hammering movement. Ratcheting pawls  88  continue to slip within detents  82  until the beater assembly has been driven through the toner and thus softened it from its hardened state. 
   In an alternative embodiment, alternating teeth  54  on support members  55  add strength and rigidity to the support members. Teeth  54  enable support members to plow through compacted toner, or alternatively “chip away” the compacted toner through the ratcheting motion of the apparatus. 
   Operation of Sensing Apparatus 
   During the operation of the apparatus ( FIG. 18 ), toner sensing device  60  leads protruding support members  55  as primary shaft  50  and encoder axle  70  rotate ( FIG. 18A ). Sensing device  60  and support members  55  are not in contact as they move through the void of the toner container area above the body of toner. As the mechanism rotates through the toner chamber, sensing device  60  comes into contact with the toner where it stops ( FIG. 18B ) until support structures  55  of primary driving shaft  50  engage it ( FIG. 18C ) and drive it through the toner ( FIG. 18D ). When toner sensing device  60  emerges from the body of toner it springs forward and the cycle begins again ( FIG. 18E ). Through this operation, encoder axle  70  and encoder disk  75  communicate to the printer the level of toner contained within the total cartridge. Most printers employ a photo-optic system that determines the toner level by determining the location and timing measurements of voids within a timing disk (such as encoder disk  75 ) integral to the encoder axle. The printer determines the toner level by registering the point of contact where the toner level sensing device meets with the toner. 
   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. 
   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.