Lexmark Patent Issued for Toner Cartridge Having a Shutter & Air Duct

[news]

Lexmark Patent Issued for Toner Cartridge Having a Shutter &  Air Duct
Lexmark : Patent Issued for Toner Cartridge Having a Shutter That Includes an Air Duct Therethrough

By a News Reporter-Staff News Editor at Computer Weekly News — Lexmark International, Inc. (Lexington, KY) has been issued patent number 9037051, according to news reporting originating out of Alexandria, Virginia, by VerticalNews editors.

The patent's inventors are Leemhuis, James Richard (Lexington, KY); Hackney, Gary Neal (Georgetown, KY).

This patent was filed on May 19, 2014 and was published online on May 19, 2015.

From the background information supplied by the inventors, news correspondents obtained the following quote: "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.

"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.RTM. or VERSAPORE.RTM., 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."

Supplementing the background information on this patent, VerticalNews reporters also obtained the inventors' summary information for this patent: "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."

For the URL and additional information on this patent, see: Leemhuis, James Richard; Hackney, Gary Neal. Toner Cartridge Having a Shutter That Includes an Air Duct Therethrough. U.S. Patent Number 9037051, filed May 19, 2014, and published online on May 19, 2015. Patent URL: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=9037051.PN.&OS=PN/9037051RS=PN/9037051

Lexmark Patent Issued for Toner Cartridge Having a Shutter &  Air Duct
Lexmark : Patent Issued for Toner Cartridge Having a Shutter That Includes an Air Duct Therethrough

By a News Reporter-Staff News Editor at Computer Weekly News — Lexmark International, Inc. (Lexington, KY) has been issued patent number 9037051, according to news reporting originating out of Alexandria, Virginia, by VerticalNews editors.

The patent's inventors are Leemhuis, James Richard (Lexington, KY); Hackney, Gary Neal (Georgetown, KY).

This patent was filed on May 19, 2014 and was published online on May 19, 2015.

From the background information supplied by the inventors, news correspondents obtained the following quote: "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.

"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.RTM. or VERSAPORE.RTM., 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."

Supplementing the background information on this patent, VerticalNews reporters also obtained the inventors' summary information for this patent: "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."

For the URL and additional information on this patent, see: Leemhuis, James Richard; Hackney, Gary Neal. Toner Cartridge Having a Shutter That Includes an Air Duct Therethrough. U.S. Patent Number 9037051, filed May 19, 2014, and published online on May 19, 2015. Patent URL: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=9037051.PN.&OS=PN/9037051RS=PN/9037051

[Author]

May 28, 2015 at 12:18 PM