1. Field of the Disclosure
The present disclosure relates generally to toner cartridges used in electrophotographic imaging devices such as a printer or multifunction device having printing capability, and in particular to a pressure equalization system used for toner cartridges.
2. Description of the Related Art
In toner cartridge design, it is now common practice to separate the longer lived components from those having a shorter life. This has lead to having the longer lived developing components such as the developer roll, toner adder rolls, doctor blades, the foregoing are also referred to as a developing unit, photoconductive drums, cleaning and charge rollers and a waste bin to be in separate assemblies from the toner cartridge. The toner supply, which is consumed relatively quickly in comparison to the previously described components, is provided in a reservoir in a separate toner cartridge that mates with the developer unit. The toner cartridge has a reduced number of components and is often referred to as a toner bottle even though it is more than a mere bottle for holding toner.
To deliver the toner from the toner cartridge to the developer unit, an auger in the toner cartridge may be used to feed toner from the toner cartridge via an exit port on the toner cartridge into an entry port on the developer unit and into a second auger that disperses the toner within the developer unit. As the toner is drawn out of the cartridge unit, it is augured through a shutter used for sealing the exit port of the toner cartridge when it is not inserted in the imaging apparatus.
While moving toner through the restriction formed by the shutter, auger and exit port, the opening from the exit port into the toner reservoir in the toner cartridge is relatively air tight. A low pressure condition or vacuum-like condition is created in the toner cartridge as toner is removed as air cannot enter to fill the void. If the toner cartridge were viewed as being a pump supplying toner from the toner reservoir, this low pressure condition would be analogous to cavitation in a pump.
In the same manner, as toner is augured into the developer unit, it passes through another shutter used to prevent toner from escaping the developer when the cartridge is not installed in the printer. This opening restricts airflow, therefore, as toner is dispensed into the developer unit, air must be displaced and a positive pressure is created in the developer unit. Further, the rotation of the developer roll causes the developer unit to ingest air further increasing the positive pressure in the developer unit. Toner being delivered from the toner cartridge to the developer unit must travel against this positive pressure gradient. This causes a significant reduction in the flow rate of the toner which can lead to failures such as incorrect cartridge empty indications, developer packing, or developer unit starvation.
This described pressure differential between the toner cartridge and developer unit necessitated that a vent be used to equalize the pressure between the developer unit and the toner cartridge. Previous venting methods for the toner cartridge included having a vent hole through the toner cartridge into the toner reservoir. Labyrinth type vent plugs, vent plugs of a porous material, and even foam tape have been used to vent air into the toner cartridge while preventing toner from escaping the toner cartridge through the vent hole. However, these methods were not successful in equalizing the pressure between the developer unit and the toner cartridge as these vent plug designs and foams tended to become clogged with toner. Further, even with the vent plugs being clear and the toner cartridge no longer in a low pressure state, venting of the higher pressure air in the developer unit back into the toner cartridge was problematic due to the restriction caused by the shutter for the exit port of the toner cartridge still causing the aforementioned pressure differential to exist between the toner cartridge and the developer unit.
In other previous toner cartridge designs, the developer unit and cartridge unit were permanently mated together so there was open fluid communications between the developer unit and the toner reservoir so that the entire system would become pressurized due to the ingestion of air caused by the rotation of the developer roll. In some cases, an internal vent was provided within the permanently mated developer unit and toner reservoir. These cartridges vented the higher internal air pressure to the atmosphere. The vent was typically made out of a porous woven material, such as GORTEX® or VERSAPORE®, or felt. These venting methods were all designed around the principle of letting air out of the cartridge while filtering and restricting toner particles from escaping. They also required the filter to be placed in a position on the cartridge that was not buried under toner. However, faster process speeds, larger toner loads, as well as separating the toner cartridge and developer unit make these methods inadequate.
To solve the pressure differential problem, it would be advantageous to have a pressure equalization system to give air a path to move from a high pressure developer unit to a low pressure toner cartridge through the exit port of the toner cartridge. It would be a further advantage to have such a ducting system be sealable to prevent toner from escaping the toner cartridge during shipping, storage, and when removed from the imaging apparatus. It would be a further advantage to be able to provide a high rate of toner delivery that helps avoid a number of previously mentioned toner delivery failures.
A toner cartridge for use in an imaging device according to one example embodiment includes a housing having a reservoir enclosed therein for holding a quantity of toner. The housing has an exit port in communication with the reservoir for exiting toner from the toner cartridge. A shutter is mounted on the housing and has a toner path through the shutter. The toner path includes an exit opening. The shutter is moveable between a closed position where the toner path is closed to the exit port preventing toner from exiting the toner cartridge and an open position where the exit opening is open to the exit port allowing toner to exit the toner cartridge. The shutter has an air duct therethrough separated from the toner path. The air duct has a first end in fluid communication with the exit port when the shutter is in the open position.
A shutter for use in a toner cartridge of an imaging device according to one example embodiment includes a toner path. The toner path includes an entrance opening positioned to receive toner and an exit opening positioned to exit toner from the toner path. An air duct through the shutter is separated from the toner path. The air duct has a first opening positioned next to the exit opening of the toner path. The air duct has a second opening.
The above-mentioned and other features and advantages of the disclosed embodiments, and the manner of attaining them, will become more apparent and will be better understood by reference to the following description of the disclosed embodiments in conjunction with the accompanying drawings.
It is to be understood that the present disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The present disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted,” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. In addition, the terms “connected” and “coupled” and variations thereof are not restricted to physical or mechanical connections or couplings.
Spatially relative terms such as “top”, “bottom”, “front”, “back”, “rear” and “side” “under”, “below”, “lower”, “over”, “upper”, and the like, are used for ease of description to explain the positioning of one element relative to a second element. These terms are generally used in reference to the position of an element in its intended working position within an imaging device. The terms “left” and “right” are as viewed with respect to the insertion direction of a unit into the imaging device. These terms are intended to encompass different orientations of the device in addition to different orientations than those depicted in the figures. Further, terms such as “first”, “second”, and the like, are also used to describe various elements, regions, sections, etc. and are also not intended to be limiting. Like terms refer to like elements throughout the description.
As used herein, the terms “having”, “containing”, “including”, “comprising”, and the like are open ended terms that indicate the presence of stated elements or features, but do not preclude additional elements or features. The articles “a”, “an” and “the” are intended to include the plural as well as the singular, unless the context clearly indicates otherwise.
The term “image” as used herein encompasses any printed or digital form of text, graphic, or combination thereof. The term “output” as used herein encompasses output from any printing device such as color and black-and-white copiers, color and black-and-white printers, and so-called “all-in-one devices” that incorporate multiple functions such as scanning, copying, and printing capabilities in one device. The term “button” as used herein means any component, whether a physical component or graphic user interface icon, that is engaged to initiate output.
Referring now to the drawings and particularly to
In the embodiment shown in
Controller 28 includes a processor unit and associated memory 29, and may be formed as one or more Application Specific Integrated Circuits (ASICs). Memory 29 may be any volatile or non-volatile memory or combination thereof such as, for example, random access memory (RAM), read only memory (ROM), flash memory, and/or non-volatile RAM (NVRAM). Alternatively, memory 29 may be in the form of a separate electronic memory (e.g., RAM, ROM, and/or NVRAM), a hard drive, a CD or DVD drive, or any memory device convenient for use with controller 28. Controller 28 may be, for example, a combined printer and scanner controller.
In the present embodiment, controller 28 communicates with print engine 30 via a communications link 50. Controller 28 communicates with imaging unit 32 and processing circuitry 44 thereon via a communications link 51. Controller 28 communicates with toner cartridge 35 and processing circuitry 45 therein via a communications link 52. Controller 28 communicates with media feed system 38 via a communications link 53. Controller 28 communicates with scanner system 40 via a communications link 54. User interface 36 is communicatively coupled to controller 28 via a communications link 55. Processing circuits 44, 45 may provide authentication functions, safety and operational interlocks, operating parameters and usage information related to imaging unit 32 or toner cartridge 35, respectively. Controller 28 serves to process print data and to operate print engine 30 during printing, as well as to operate scanner system 40 and process data obtained via scanner system 40.
Computer 24, which may be optional, may be, for example, a personal computer, network server, electronic tablet computer, smartphone or other hand-held electronic device, including memory 60, such as volatile or nonvolatile memory, an input device 62, such as a keyboard, and a display, such as monitor 64. Computer 24 further 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 includes in its memory a software program including program instructions that function as an imaging driver 66, e.g., printer/scanner driver software, for imaging apparatus 22. Imaging driver 66 is in communication with controller 28 of imaging apparatus 22 via communications link 26. Imaging driver 66 facilitates communication between imaging apparatus 22 and computer 24. One aspect of imaging driver 66 may be, for example, to provide formatted print data to imaging apparatus 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.
In some circumstances, it may be desirable to operate imaging apparatus 22 in a standalone mode. In the standalone mode, imaging apparatus 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 imaging apparatus 22 so as to accommodate printing and scanning functionality when operating in the standalone mode.
Print engine 30 may include a laser scan unit (LSU) 31, an imaging unit 32, a toner cartridge 35, and a fuser 37, all mounting within imaging apparatus 22. The imaging unit 32 further includes a cleaner unit 33 housing a waste toner removal system and a photoconductive drum, and a developer unit 34 that are removably mounted within imaging unit 32. In one embodiment the cleaner unit 33 and developer unit 34 are assembled together and installed into a frame to form the imaging unit 32. The toner cartridge 35 is then installed on the frame in a mating relation with the developer unit 34. Laser scan unit 31 creates a latent image on the photoconductive drum in the cleaner unit 33. The developer unit 34 has a toner sump containing toner which is transferred to the latent image on the photoconductive drum to create a toned image. The toned image is subsequently transferred to a media sheet received in the imaging unit 32 from media input tray 39 for printing. Toner remnants are removed from the photoconductive drum by the waste toner removal system. The toner image is bonded to the media sheet in the fuser 37 and then sent to an output location or to one or more finishing options such as a duplexer, a stapler or hole punch.
The toner cartridge 35 removably mates with the developer unit 34 in imaging unit 32. An exit port on the toner cartridge 35 communicates with an inlet port on the developer unit 34 allowing toner to be periodically transferred from the toner cartridge 35 to resupply the toner sump in the developer unit 34.
Referring now to
In
Various drive gears are housed within a space formed between first end cap 218 and first side wall 210 with main interface gear 228 being visible. Various interlocks and linkages may also be housed within the space formed between second end cap 220 and second side wall 212. Mounting structures 229 may be provided on the exterior surfaces of first and second side walls 210, 212 for use with the interlocks and linkages. Main interface gear 228 engages with a drive system within imaging apparatus 22 which provides torque to main interface gear 228. A paddle is rotatably mounted within toner reservoir 204 with first and second ends of a drive shaft of the paddle extending through aligned openings 244 in the first and second side walls 210, 212, respectively. A drive gear is provided on the first end of the drive shaft of the paddle and engages with main interface gear 228 either directly or via one or more intermediate gears. First side wall 210 may also be termed the “drive” or “driven” side of toner cartridge 200.
Referring to
Channel 250 comprises an open portion 252 and an enclosed portion 254. Open portion 252 is open to the toner reservoir 204 and extends from the first side wall 210 toward the second end 234 of auger 230. Enclosed portion 254 of channel 250 extends from the second side wall 212 and encloses a shutter 302 of shutter assembly 300 and the second end 234 of the auger 230. The paddle, as it rotates, delivers toner from the toner reservoir 204 into the first portion 252 of channel 250. Auger 230 is rotated via drive gear 238 to deliver toner received in channel 250 to the shutter 302 which is housed in the enclosed portion 254 of channel 250. An exit port 256 is provided through the wall 258 forming the enclosed portion 254 of channel 250. Shutter 302 rotates between a first position where it closes exit port 256 and a second position where exit port 256 is open. As illustrated (see also
As shown in
An example shutter assembly 300 for the toner cartridge 200 is shown in
In an example embodiment shutter 302 is generally cylindrical. Shutter 302 has a drive portion 312 and a hollow portion 314. Shutter 302 is inserted into the enclosed portion 254 of channel 250 aligning the hollow portion 314 of shutter 302 with the second end 234 of auger 230. Shutter 302 is rotatable within enclosed portion 254 of channel 250. Drive portion 312 passes through an opening 316 in retainer 304 and is rotatable within opening 316. Fasteners are inserted through openings 318 in retainer 304 and are received in corresponding openings in housing 202 rotatably securing shutter 302 in housing 202. Drive portion 312 has one or more keys 320 that are received into corresponding one or more keyways 324 in opening 322 of lever 306 to ensure proper orientation of lever 306 with shutter 302. Another fastener 308, such as a screw, passes through openings 322, 316 and is received in opening 326 provided on the end of drive portion 312 securing lever 306 to shutter 302. A connection pin 325 is provided at the distal end of lever 306 for attaching a drive linkage used for operating of lever 306. It will be realized that alternatively one or more keys may be provided on lever 306 and be received in corresponding one or more keyways provided in drive portion 312 of shutter 302. Other forms of fasteners may also be used.
Hollow portion 314 extends from an inner end 328 of the shutter 302 toward an outer end 330 of the shutter 302 and has an open end 332 and a closed end 334. Open end 332 and hollow portion 314 are sized to rotatably receive the second end 234 of auger 230 and provide support for auger 230. Exit opening 336 is provided through a wall 333 of hollow portion 314. A channel 337 is formed in shutter 302 between the open end 332 and exit opening 336 through which exiting toner passes on its way to the exit port 256. When the shutter 302 is in its second or open position, rotation of auger 230 pushes toner in channel 250 through channel 337 and out exit opening 336 where it falls through exit port 256.
A duct 340 having first and second ends 342, 344 passes through shutter 302 and is disposed within drive portion 312. First end 342 of duct 340 is positioned near exit opening 336. Example duct 340 is shown routed through shutter 302 along a diameter thereof and does not intersect with channel 337. However, other routings for duct 340 may be used through drive portion 312 of shutter 302. In one embodiment a deflection rib 338 is disposed near closed end 334 of hollow portion 314. Deflection rib 338 directs toner leaving exit opening 336 away from first end 342 of duct 340 and into exit port 256. Deflection rib 338 may extend into exit port 256. Deflection rib 338 helps to block exiting toner leaving exit opening 336 from entering duct 340.
A foam seal 350 is shown in
Referring to
Channel 450 comprises an open portion 452 and an enclosed portion 454. Open portion 452 is open to the toner sump 404 and extends from the first side wall 408 toward the second end 434 of auger 430. Enclosed portion 454 of channel 450 extends from the second side wall 410 and encloses a shutter 502 of shutter assembly 500 and the second end 434 of the auger 430. A slot 455 is provided in the enclosed portion. Auger 430 is rotated via drive gear 438 to deliver toner received in shutter 502 into the open portion 452 of channel 450 and then into toner sump 404. A toner entry port 456 is provided through the wall 458 of channel 450 forming the enclosed portion 454 of channel 450. Shutter 502 rotates between a first position where it closes entry port 456 and a second position where entry port 456 is open. As illustrated (see
Entry port 456 for toner (see
Referring now to
Example embodiment shutter 502 is generally cylindrical. Shutter 502 has a drive portion 512 and a hollow portion 514. Shutter 502 is inserted into the enclosed portion 454 of channel 450 aligning the hollow portion 514 of shutter 502 with the second end 434 of auger 430. Shutter 502 is rotatable within enclosed portion 454 of channel 450. Drive portion 512 passes through an opening 516 in retainer 504 and is rotatable within opening 516. Fasteners, such as screws, are inserted through openings 518 in retainer 504 and are received in corresponding openings in housing 402 rotatably and axially securing shutter 502 in housing 402. Drive portion 512 has one or more keys 520 that are received into corresponding one or more keyways 524 in opening 522 of lever 506 to ensure proper orientation of lever 506 with shutter 502. Another fastener 508, such as a screw, passes through opening 522 and is received in opening 526 provided on the end of drive portion 512 securing lever 506 to shutter 502. It will be realized that alternatively one of more keys may be provided on lever 506 and be received in corresponding one or more keyways provided in drive portion 512 of shutter 502. Also other forms of fasteners may also be used.
Hollow portion 514 extends from an inner end 528 of the shutter 502 toward an outer end 530 of the shutter 502 and has a open end 532 and a closed end 534. Open end 532 and hollow portion 514 are sized to rotatably receive the second end 434 of auger 430 and provide support for auger 430. Entry opening 536 is provided through a wall 538 of hollow portion 514. Example entry opening 536 is larger in area than exit opening 336 in shutter 302. Example entry opening 536 is illustrated as having to two or more radially offset or stepped sections 536A, 536B that are joined together to form entry opening 536. This arrangement of offset or stepped sections helps to prevent bridging by the entering toner and to ensure that an air flow path is maintained between the toner sump 404 and the toner entry port 456. A channel 537 is formed in shutter 502 between the open end 532 and exit opening 536 through which entering toner passes on its way to channel 450. When the shutter 502 is in its second or open position, rotation of auger 430 pulls toner from channel 537 and out open end 532 and into channel 450. With the shutter in its first or closed position, the shutter blocks slot 455 and the second end 434 of auger 430 and toner block the open end 532 of shutter 502.
A foam seal, similar to form seal 350, is wrapped around shutter 502. Foam seal has an opening therethrough disposed about entry opening 536. Foam seal is used to seal the space between shutter 502 and the enclosed portion 454 of channel 450 to prevent the leakage of toner around entry port 456. As is known in the art, the ends of foam seal may use curvilinear or wavy edges where they join together creating a labyrinth joint to inhibit toner leakage through this area of the foam seal 550.
In one form, the drive and hollow portions of shutters 302, 502, taper inwardly from their respective outer ends 330, 530 towards their respective inner ends 328, 528.
The portion of the air flow path from the toner sump 404 to entry port 456 may be termed the developer unit airway. By activating the toner cartridge airway, a vent is opened that allows air in the developer unit 400 to bypass the airflow restrictions in shutter assembly 300 and flow into the top of the toner cartridge 200. The higher pressure air in the developer unit 400 exits via the developer unit airway and enters toner cartridge 200 via the toner cartridge airway. This eliminates the vacuum or low pressure region in the toner reservoir 204 of toner cartridge 200 as toner is removed, allows for maximum toner flow from the exit port 256, and pressure equalization between the toner cartridge 200 and developer unit 400. The positioning of shutter assembly 500 in channel 450 and the positioning channel 450 and entry port 456 above the level of the toner contained within toner sump 404 helps to ensure that the developer unit airway remains clear.
To prevent a user from having to intervene with activating the toner cartridge airway, the passageway 260 is routed through the duct 340 of cartridge shutter 302. One advantage of this routing is that if the toner cartridge airway runs through shutter 302 of toner cartridge 200, when the toner cartridge 200 is removed, the toner therein is double sealed by the reed valve 274 and shutter 302. This prevents toner from leaking out of the cartridge during drop testing or shipping. Another advantage is that by having the toner cartridge airway run through the shutter 302 and exit port 256 locates the duct 340 directly over the developer unit toner entry port 456. This connects the duct 340 and passageway 260 to the developer unit 400 using preexisting connections, eliminating user intervention and eliminating the need to have a separate airway opening in each of the toner cartridge 200 and developer unit 400 unit which may provide another path for toner leakage. When the user installs the toner cartridge 200 into the imaging unit 100, a linkage is moved by the toner cartridge 200 actuating shutter assembly 500 and moving shutter 502 into its second or open position. When the toner cartridge 200 is fully seated in the imaging unit 100, a door over that toner cartridge 200 can then be closed by a user and a rod or plunger on the interior of the door actuates shutter assembly 300 and moving shutter 302 into its second or open position. At this time the toner cartridge airway and the developer unit airway are activated with both shutter assemblies 300, 500 being in their respective open positions.
The foregoing description of several methods and an embodiment of the invention has been presented for purposes of illustration. It is not intended to be exhaustive or to limit the invention to the precise steps and/or forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be defined by the claims appended hereto.
This patent application is a continuation application of U.S. patent application Ser. No. 13/340,830, filed Dec. 30, 2011, entitled “Imaging Apparatus Assembly with Pressure Equalization.” The present application is related to U.S. patent application Ser. No. 13/340,814, filed Dec. 30, 2011, entitled “Toner Cartridge With Pressure Equalization System” and assigned to the assignee of the present application.
Number | Date | Country | |
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Parent | 13340830 | Dec 2011 | US |
Child | 14280733 | US |