Patent application number | Description | Published |
20080219701 | SQUAREWAVE CHARGING OF A PHOTORECEPTOR - Charging devices, electrostatic imaging devices, and methods generate a charging waveform having a DC bias component and an AC component for charging the imaging surface of a charge retentive member, the AC component having a substantially squarewave waveform. | 09-11-2008 |
20080226353 | APPARATUS AND METHODS FOR LOADING A DONOR ROLL UTILIZING A SLOW SPEED TRIM ROLL - An apparatus for loading one or more donor rolls of a developer unit, comprising a developer housing having a reservoir for a developer material, a rotatable first donor roll that delivers the toner onto a moving photoconductive member, a trim roll that receives developer material from the reservoir and delivers the developer material to a first magnetic brush roller that delivers toner to the first donor roll, and a rotatable second magnetic brush roll that receives the developer material from the first magnetic brush roll and delivers the toner to the first donor roll. The apparatus may further comprise a rotatable second donor roll that receives the toner from the second magnetic brush roll and delivers the toner onto the photoconductive member, and a rotatable third magnetic brush roll that receives the developer material from the second magnetic brush roll and delivers the toner to the second donor roll. The apparatus may further comprise a trim blade for trimming excess developer material from the trim roll. | 09-18-2008 |
20080226354 | APPARATUS AND METHODS FOR LOADING A DONOR ROLL - An apparatus for loading one or more donor rolls of a developer unit, comprising a developer housing having a reservoir for a developer material, a rotatable first donor roll that delivers the toner onto a moving photoconductive member, a rotatable first magnetic brush roll that receives the developer material from the reservoir and delivers the toner to the first donor roll, and a rotatable second magnetic brush roll that receives the developer material from the first magnetic brush roll and delivers the toner to the first donor roll. The apparatus may further comprise a rotatable second donor roll that receives the toner from the second magnetic brush roll and delivers the toner onto the photoconductive member, and a rotatable third magnetic brush roll that receives the developer material from the second magnetic brush roll and delivers the toner to the second donor roll. | 09-18-2008 |
20100092200 | OPTIMIZATION OF RELOAD PERFORMANCE FOR PRINTER DEVELOPMENT SYSTEMS WITH DONOR ROLLS - A method creates a printing image charge on a photoreceptor printing region of a photoreceptor within a printing apparatus and, simultaneously with the creating of the printing image charge, charges source patches on the photoreceptor outside the photoreceptor printing region. The method then transfers developer material from a donor roll to the photoreceptor. The source patches cause developer material to be removed from areas of the donor roll outside a donor roll printing region to create developer material-depleted regions. The method then reloads the donor roll with developer material using a magnetic brush and evaluates a reload function of the donor roll by characteristics of developer material on target patches with developer material in areas of the non-printing region of the photoreceptor adjacent the target patches. The method then alters the printing image charge to maintain the reload function within a predetermined range. | 04-15-2010 |
20100194842 | METHOD AND APPARATUS FOR CORRECTING BANDING DEFECTS IN A PHOTORECEPTOR IMAGE FORMING APPARATUS - A method and apparatus for correcting banding defects in a photoreceptor image forming apparatus. The method or apparatus may form one or more images using one or more laser beams to alter an electrostatic charge on a photoreceptor, check the one or more images for one or more sets of image perfections arising from electric field attenuation in the photoreceptor, and compensate for the electric field attenuation. The method or apparatus may further form a compensated image. | 08-05-2010 |
20110026945 | XEROGRAPHIC PROCESS CONTROLS SCHEDULING APPROACH TO MITIGATE COSTS OF MEASUREMENT - A method and apparatus for maintaining color consistency includes varying a sampling interval to balance the benefit of xerographic process controls regulation with the cost of sampling. The request to sample is triggered by external indicators (area coverage, carrier age, relative humidity, temperature, etc.). Before the developed mass is expected to go out of range because of the external indicators, a patch measurement is made and the system is controlled back towards its desired set-point. | 02-03-2011 |
20110280606 | DYNAMIC DONOR LOADING CONTROL FOR DEVELOPMENT SYSTEM - A method and apparatus transfer a material from first roller within a container to at least one second roller, and transfer the material from the second roller to at least one third roller. The second roller and the third roller form a loading nip at a location where the second roller is closest to the third roller. The method and apparatus transfer the material from the third roller to at least one recipient device, and measure current flow between the second roller and the third roller using a measurement device. Then, the method alters the relative rotation rate difference between the first roller and the second roller based on the current flow to maintain a predetermined density of the material at the loading nip using a controller. | 11-17-2011 |
20120148272 | METHOD AND APPARATUS FOR COMPENSATION OF BANDING FROM MULTIPLE SOURCES IN MARKING PLATFORM - A method for compensation of banding in a marking platform includes: initiating a calibration stage; marking a test pattern over multiple intervals of a lowest fundamental frequency among marking modules; obtaining image data for the test pattern from a sensor; obtaining 1x signals from sensors associated with the marking modules; and processing the image data in relation to the 1x signals to form banding profiles for multiple marking modules. Alternatively, the method may include: processing image data in relation to 1x signals to form banding profiles for multiple marking modules; determining amplitudes in multiple banding profiles exceeds a threshold to identify dominant banding profiles; and processing dominant banding profiles to form dominant banding signatures. Alternatively, the method may include: initiating a correction stage; obtaining 1x signals from sensors associated with dominant marking modules; and periodically processing dominant banding signatures and 1x signals to determine a banding compensation value. | 06-14-2012 |
20120250037 | METHOD AND APPARATUS FOR COMPENSATION OF ARBITRARY BANDING SOURCES USING INLINE SENSING AND CONTROL - A method for compensation of banding in a marking platform includes: initiating a signature learning mode; establishing a timing reference after marking modules have achieved constant velocity; marking a test pattern over multiple intervals of a lowest fundamental frequency among marking modules; obtaining image data for the test pattern from a sensor; and processing the image data in relation to the timing reference to form banding profiles for multiple banding sources. Alternatively, the method may include: initiating a cycle up stage in a phase learning mode; establishing a timing reference after marking modules have achieved constant velocity; marking a test pattern over multiple intervals of a lowest fundamental frequency among marking modules; obtaining banding image data for the test pattern from a sensor; and processing the image data with banding signatures in relation to the timing reference to form phase estimates for each banding signature. Additional embodiments are also provided. | 10-04-2012 |
20130050327 | INKJET PRINTER WITH PARTIAL IMAGE RECEIVING MEMBER HEATING - A method for operating an image receiving member in a phase change ink printer has been developed. The method includes selectively rotating the image receiving member past an activated heater to heat a first portion of the image receiving member to a first predetermined temperature that is greater than a second temperature to which a remaining portion of the image receiving member is heated by the heater. | 02-28-2013 |
20130070037 | TRANSFIX ROLLER FOR USE IN AN INDIRECT PRINTER WITH AN IMAGE RECEIVING MEMBER HAVING A THIN WALL - A transfix roller is adapted for use with a thin walled image receiving member in an indirect printer. The transfix roller is centrally supported to present a more uniform pressure profile in the nip formed with the image receiving member. An interference fit between the central shaft and the roller sleeve enables the transfix roller to be made without an additional process to secure the shaft to the sleeve. | 03-21-2013 |
20130129365 | METHOD AND SYSTEM FOR TROUBLESHOOTING CHARGING AND PHOTORECEPTOR FAILURE MODES ASSOCIATED WITH A XEROGRAPHIC PROCESS - This disclosure provides methods and systems for troubleshooting charging and photoreceptor failure modes associated with a xerographic process. Specifically, according to an exemplary method the photoreceptor decay behavior, with and without the effects of depletion, are quantified and used to determine a performance state of one or more of the charging stations and the photoreceptor surface. | 05-23-2013 |
20130216248 | METHOD AND APPARATUS FOR COMPENSATION OF BANDING FROM MULTIPLE SOURCES IN MARKING PLATFORM - A method for compensation of banding in a marking platform includes: initiating a calibration stage; marking a test pattern over multiple intervals of a lowest fundamental frequency among marking modules; obtaining image data for the test pattern from a sensor; obtaining 1× signals from sensors associated with the marking modules; and processing the image data in relation to the 1× signals to form banding profiles for multiple marking modules. Alternatively, the method may include: processing image data in relation to 1× signals to form banding profiles for multiple marking modules; determining amplitudes in multiple banding profiles exceeds a threshold to identify dominant banding profiles; and processing dominant banding profiles to form dominant banding signatures. Alternatively, the method may include: initiating a correction stage; obtaining 1× signals from sensors associated with dominant marking modules; and periodically processing dominant banding signatures and 1× signals to determine a banding compensation value. | 08-22-2013 |
20130293616 | Transfix Roller with Adaptive Center Loading for Use in an Indirect Printer - An image transfer system for use in an indirect printer includes a support roller for a transfix roller. The support roller is configured to apply pressure to a center portion of a nip formed between a transfix roller and an imaging drum while the transfix roller applies pressure to the ends of the nip. This configuration is particularly advantageous for use with imaging drums and transfix rollers having thin walls. | 11-07-2013 |
20130328983 | Inkjet Printer having an Image Drum Heater with Heater Seals - An inkjet offset printer includes a heated drum assembly having a hollow drum with an internal surface defining an internal cavity and a heater located in the internal cavity. The heater includes a reflector having a seal, and at least one heating element configured to generate heat and disposed between the reflector and the internal surface of the drum. The seal contacts the internal surface of the hollow drum to confine the generated heat within a space defined by the reflector and the internal surface of the drum. | 12-12-2013 |
20130328989 | Inkjet Printer having an Image Drum Heating and Cooling System - An inkjet offset printer includes an image receiving drum assembly having a hollow drum with an external surface and an internal surface defining an internal cavity. A heating and a cooling system located in the internal cavity provides distributed heating and cooling to the internal surface of the drum. Heating and cooling can be provided to individual regions of the internal drum surface to maintain a substantially uniform external drum surface temperature. | 12-12-2013 |
20130335473 | System and Method for Printing Full-Color Composite Images in an Inkjet Printer - An inkjet printer includes a plurality of color separation modules. Each color separation module includes an image receiving member and a printhead module configured to eject ink drops onto the image receiving member to form a color separation on the image receiving member. The printer is configured to transfix each color separation on each image receiving member to a single sheet to produce a composite ink image on the print medium after the print medium has passed by all of the color separation modules in the printer. | 12-19-2013 |
20130335476 | SYSTEM AND METHOD FOR IMPROVING TEMPERATURE UNIFORMITY OF IMAGE DRUMS - A printer includes an image drum temperature regulation system that helps reduce thermal gradients on the image drum surface. The image drum temperature regulation system includes a feedback controller and a feed-forward controller. The image drum temperature regulation system operates the heaters and fan of the image drum with reference to a temperature difference between actual temperature of the image drum and a temperature setpoint and to the thermal effect of ejecting an ink image onto the image drum. | 12-19-2013 |
20130335752 | Transfix Roller with Adjustable Crown for Use in an Indirect Printer - An indirect printer includes a system for alternating the pressure in a transfer nip by manipulating the transfer roller. The system includes a pair of pivotable collars mounted about the ends of the transfer roller. The collars are pivoted towards or away from one another to bend the transfer roller and to increase or decrease, respectively, the pressure in the longitudinal center of the nip. | 12-19-2013 |
20140028769 | SYSTEM AND METHOD FOR REDUCING ELECTROSTATIC FIELDS UNDERNEATH PRINT HEADS IN AN ELECTROSTATIC MEDIA TRANSPORT - Embodiments described herein are directed to a system for reducing electrostatic fields underneath print heads in a direct marking printing system. The system includes: one or more print heads for depositing ink onto a media substrate; a media transport for moving the media substrate along a media path past the one or more print heads; a conductive platen contacting the media transport belt; and an electrostatic field reducer that includes an alternating current corona device positioned upstream of the one or more print heads. The media transport includes a media transport belt and, when the media substrate is on the transport belt it has an electrostatic field, which can cause printing defects. The electrostatic field reducer reduces the electrostatic field on the surface of the media substrate and thereby reduces printing defects. | 01-30-2014 |
20140168313 | System And Method For Controlling Dewpoint In A Print Zone Within An Inkjet Printer - An aqueous inkjet printer includes a print zone with a relative humidity sensor and a temperature sensor. A controller identifies a dew point of air between a printhead and an intermediate imaging member with reference to the air temperature and the moisture in the air of the print zone, and identifies a target dew point with reference to the image data used to operate the printhead. The controller operates a heater and an air mover to adjust the dew point of the air between the printhead and the intermediate imaging member to the target dew point. | 06-19-2014 |
20140184712 | SEMI-CONDUCTIVE MEDIA TRANSPORT FOR ELECTROSTATIC TACKING OF MEDIA - A semi-conductive media transport is used with an ink jet printing system. A belt is held flat and slides across a conductive platen, causing electrostatic charges on the belt. The belt is made semi-conductive to prevent charge buildup. The belt has an effective surface resistivity between a lower limit to preclude a buildup of electrostatic charges, and an upper limit to enable electrostatic tacking of the media to the belt. The resistivity limits vary depending upon belt velocity, thickness, material, belt and media dielectric constant, and slot width. A pair of charged nip rollers tacks the media substrate to the belt. An AC corotron is disposed above the belt to establish a net neutral charge state on the media substrate and the belt. Platen slots directly below the ink jet print heads will maintain the net neutral charge state on the media substrate and the belt. | 07-03-2014 |
20140198164 | Inkjet Printer Having An Image Drum Heating And Cooling System - An inkjet offset printer includes an image receiving drum assembly having a hollow drum with an external surface and an internal surface defining an internal cavity. A heating and a cooling system located in the internal cavity provides distributed heating and cooling to the internal surface of the drum. Heating and cooling can be provided to individual regions of the internal drum surface to maintain a substantially uniform external drum surface temperature. | 07-17-2014 |
20140204157 | Pressure Roller Containing A Volume Of Fluid - A pressure roller for a media processing device has enhanced temperature uniformity and resists temperature increases when subjected to elevated temperatures, enabling greater dimensional stability of the pressure roller in fluctuating temperatures. The pressure roller includes a hollow cylindrical member, an elastomeric layer, and an endbell on each end of the hollow cylindrical member. A chamber is defined by an inner wall of the hollow cylindrical member and the endbells in which a volume of fluid is contained to absorb heat from the hollow cylindrical member. | 07-24-2014 |
20140267501 | Active Biased Electrodes for Reducing Electrostatic Fields Underneath Print Heads in an Electrostatic Media Transport - Embodiments described herein are directed to a system for reducing electrostatic fields underneath print heads in a direct marking printing system. The system includes: one or more print heads for depositing ink onto a media substrate; a media transport for moving the media substrate along a media path past the one or more print heads; a conductive platen contacting the media transport belt; an electrostatic field reducer that includes an alternating current charge device positioned upstream of the one or more print heads; and one or electrically isolated biased electrodes in registration with the ink deposition areas of the one or more print heads. The media transport includes a media transport belt and, when the media is on the transport belt it has an electrostatic field, which can cause printing defects. The electrostatic field reducer and electrodes reduce the electrostatic field on the surface of the media and thereby reduce printing defects. | 09-18-2014 |