Write heating architecture for dual mode imaging systems

A dual mode imaging system includes an ink jet device for imaging non-erasable media and a write device for imaging erasable media. A media transport subsystem is provided for supplying non-erasable and erasable media to one of the ink jet device and the write device. A heat source is incorporated into the media transport subsystem, and particularly in connection with a guide baffle of the ink jet device, the heat source heating erasable media to a temperature suitable for imaging at the write device.

FIELD OF THE INVENTION

This invention relates generally to imaging and, more particularly, to imaging both reversible write erasable media and non-erasable paper in an imaging system.

BACKGROUND OF THE INVENTION

Paper documents are often promptly discarded after being read. Although paper is relatively inexpensive, the quantity of discarded paper documents is enormous and the disposal of these discarded paper documents raises significant cost and environmental issues. It would, therefore, be desirable for paper documents to be reusable, to minimize both cost and environmental issues.

Erasable media is that which can be reused many times to transiently store images, the images being written on and erasable from the erasable media. For example, photochromic paper employs photochromic materials to provide an imageable surface. Typically, photochromic materials can undergo reversible or irreversible photoinduced color changes in the photochromic containing layer. In addition, the reversible photoinduced color changes enable imaging and erasure of photochromic paper in sequence on the same paper. For example, a light source of a certain wavelength can be used for imaging erasable media, while heat can be used for inducing erasure of imaged erasable media. An inkless erasable imaging formulation is the subject of U.S. patent application Ser. No. 12/206,136 filed Sep. 8, 2008 and titled “Inkless Reimageable Printing Paper and Method” which is commonly assigned with the present application to Xerox Corp., and is incorporated in its entirety herein by reference.

Because imaging of erasable media has unique requirements, it has previously required dedicated equipment. In particular, a UV source can be required to image the erasable media, and heat can be required to erase an imaged erasable media. In addition, specific temperature parameters are required for each of the imaging and erasing of erasable media. While traditional imaging devices are suitable for performing conventional imaging of non-erasable media, their architecture can be insufficient for handling erasable media alone or in combination with non-erasable media.

Thus, there is a need to overcome these and other problems of the prior art and to provide a dual mode imaging device in which both erasable media and non-erasable paper can be selectively imaged. Even further, the dual mode imaging device should be capable of interchangeably sharing imaging components.

SUMMARY OF THE INVENTION

According to various embodiments, the present teachings include a dual mode imaging system. This system includes an ink jet device for imaging non-erasable media; a write device for imaging erasable media; a media transport subsystem for supplying non-erasable and erasable media to one of the ink jet device and the write device; and a heat source incorporated into the media transport subsystem, the heat source heating erasable media to a temperature suitable for imaging at the write device.

According to various embodiments, the present teachings include a dual mode imaging device. The device includes an ink jet device for imaging non-erasable media; a write device for imaging erasable media; and a heat source incorporated into a paper advance guide baffle of the ink jet device, an imaging temperature of an erasable medium established by the heat source.

According to various embodiments, the present teachings also include a method of dual mode imaging. This method includes incorporating a heat source with a paper advance guide baffle of an ink jet imaging device, the guide baffle forming a common media path for each of erasable media and non-erasable media; establishing, via the heat source, an imaging temperature of an erasable medium; selectively imaging erasable media at the imaging temperature with a write device; selectively imaging non-erasable media with the ink jet device; and cooling an imaged erasable medium.

It should be noted that some details of the figures have been simplified and are drawn to facilitate understanding of the inventive embodiments rather than to maintain strict structural accuracy, detail, and scale.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the present embodiments (exemplary embodiments) of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. In the following description, reference is made to the accompanying drawings that form a part thereof and in which is shown by way of illustration specific exemplary embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the invention. The following description is, therefore, merely exemplary.

As used herein, the term “erasable media” refers to transient material that has the appearance and feel of traditional paper, including cardstock and other weights of paper. Erasable media can be selectively imaged and erased.

As used herein, imaged erasable media refers to erasable media having a visible image thereon, the image a result of, for example, ultraviolet (UV) imaging of the erasable media.

As used herein, non-imaged erasable media refers to erasable media which has not been previously imaged, or erasable media having an image erased therefrom and available for UV imaging. An exemplary erasable medium is described in connection withFIG. 1below.

As used herein, the term “non-erasable” refers to traditional media of the type used in any conventional imaging such as ink jet, xerography, or liquid ink electrophotography, as known in the art. An example of a non-erasable traditional medium can be conventional paper.

FIG. 1depicts an exemplary erasable medium100in accordance with the present teachings. It should be readily apparent to one of ordinary skill in the art that the erasable medium100depicted inFIG. 1represents a generalized schematic illustration and that other layers can be added or existing layers can be removed or modified.

As shown inFIG. 1, the erasable medium100can include a substrate110and a photochromic material120incorporated into or on the substrate110. The photochromic material120can provide a reversible writing (i.e. erasable) image-forming component on the substrate110.

The substrate110can include, for example, any suitable material such as paper, wood, plastics, fabrics, textile products, polymeric films, inorganic substrates such as metals, and the like. The paper can include, for example, plain papers such as XEROX® 4024 papers, ruled notebook paper, bond paper, and silica coated papers such as Sharp Company silica coated paper, Jujo paper, and the like. The substrate110, such as a sheet of paper, can have a blank appearance.

In various embodiments, the substrate110can be made of a flexible material and can be transparent or opaque. The substrate110can be a single layer or multi-layer where each layer is the same or different material and can have a thickness, for example, ranging from about 0.05 mm to about 5 mm.

The photochromic material120can be impregnated, embedded or coated to the substrate110, for example, a porous substrate such as paper. In various embodiments, the photochromic material120can be applied uniformly to the substrate110and/or fused or otherwise permanently affixed thereto.

Portion(s) of photochromic material of an imaged erasable medium100can be erased. In order to produce the transition from a visible image to an erased medium, heat can be applied to the erasable medium100at a temperature suitable for effecting the erasure. For example, at a temperature between about 80° C. to about 200° C., the erasable medium100can be completely erased. In certain embodiments, the erasable medium can be erased at ambient temperature and with light in the visible spectrum. In order to re-image the erased (or image an original) erasable medium100, the erasable medium100can be heated to a temperature of between about 55° C. to about 80° C. before writing using, for example, UV exposure.

It will be appreciated that other types of erasable media, other than photochromic paper, can be used in connection with the exemplary embodiments herein. Such types of erasable media are intended to be included within the scope of the disclosure.

While the temperatures for processing erasable media can be achieved and maintained in a single mode device for imaging and erasing erasable media, the following describes an exemplary incorporation of a dual mode imaging system capable of processing erasable media as well as producing traditional (non-erasable) prints and copies. The traditional prints and copies can be produced by ink jet. The ink jet can include aqueous ink jet, solid ink jet and gel ink jet.

FIG. 2depicts an exemplary dual mode imaging system200incorporating each of an ink jet printer and an erasable media write system in accordance with the present teachings. It should be readily apparent to one of ordinary skill in the art that the dual mode imaging system200depicted inFIG. 2represents a generalized schematic illustration and that other components can be added or existing components can be removed or modified.

As shown inFIG. 2, the dual mode imaging system200can include housing210with media input220and output230locations. In addition, the dual mode imaging system200can include a conventional imaging subsystem240, an erasable media write subsystem260, a temperature management subsystem250, a user interface280, a control system290, and an administrator interface295.

The housing210can be of a material and size to accommodate the exemplary components of the dual mode imaging system200. In certain embodiments, the housing210can include a desktop device. The housing210can further include a full size floor supported device. Sizes for each are known in the art and not intended to limit the scope of the invention.

The media inputs220can include one or more input trays for each of an erasable media and non-erasable media. As used herein, if an erasable media is in the original state, i.e. not previously imaged, it can also be referred to as an “erased” erasable media for ease of description. For the erasable media, separate input trays can be provided for each of erased and imaged erasable media in order to distinguish an operation within the dual mode imaging system200relevant to each. Other combinations of media are intended to be within the scope of the disclosure. Although the input trays are initially labeled by example and purposes of discussion according to the type of media therein; their relative arrangement both interior and exterior to the housing210can be altered according to a configuration of components within the housing210.

In embodiments, a sensor225can be provided to detect a type of media entering the dual mode imaging device200. The sensor225can be proximate each input tray220, incorporated in the input tray220, or interior of the housing210. For example, the sensor225can detect an erasable media100and control system290can select activation or use of one of a conventional imaging subsystem240or the erasable media write subsystem260.

The selected medium can be moved along an imaging path in the direction noted by the arrows. Single sheets of the selected medium are fed from input220by document feed roll222driven by a motor M under the control of a printer controller (not shown). The input220can be spring biased by biasing mechanism224which forces the top sheet of a stack of media into contact with the feed roller222. A top most medium, in contact with the feed roller222, is transported into the temperature management subsystem250, details of which are described further in connection withFIGS. 3A and 3B.

The conventional imaging subsystem240can include components suitable for imaging a non-erasable media. In certain embodiments, the imaging subsystem240can include an ink jet imaging system. The conventional ink jet imaging subsystem240can include a translating ink jet printhead depositing black and/or colored ink drops through a plurality of nozzles is supported by a housing which moves back and fourth across the non-erasable medium, on a guide rail242and a supporting shelf244as known in the art. Multiple print heads printing different colors are within the scope of this invention as well as a single printhead being segmented for printing different colors. The ink jet subsystem240can include any of solid ink jet, gel ink jet and aqueous ink jet whose structure and function are known in the art.

In certain embodiments, the write subsystem260can include imaging components suitable for imaging erasable media. For example, the write subsystem260can UV image an erasable media. In embodiments, UV imaging can be implemented once the erasable media reaches a predetermined temperature. An exemplary UV imaging temperature of an erasable media can be from about 50° C. to about 80° C. A UV imaging temperature can further be from about 60° C. to about 70° C. The UV imaging temperature can be about 65° C. Other UV, IR or similar imaging temperatures can be set according to a type of erasable media and such imaging temperatures are intended to be included within the scope of the invention.

In embodiments, the write subsystem260can include a heat source. The heat source can heat the erasable medium to a temperature suitable for imaging, for example, UV imaging. The heat source will be further described in connection withFIG. 3, below.

A front face of each of the conventional imaging device240and write subsystem260are substantially parallel to the medium being imaged. The imaging device240and write subsystem260, which travel orthogonally to the direction that the medium travels, deposit ink droplets or radiantly images the medium in an image wise fashion. The image deposited or otherwise formed on the medium includes text and/or graphic images, the creation of which is controlled by controllers290and295, in response to electrical signals transmitted through a cable246coupled to the imaging device240. A star wheel248or other known drive mechanism picks up the lead edge of an imaged medium and pulls the medium into the output230.

In certain embodiments, a user interface280can be provided in the housing210. The user interface280can include control components, responsive to user input, for directing the functions of the dual mode imaging system200. In certain embodiments, the dual mode imaging system200can be configured through the user interface280to start up in an erasable media imaging mode or conventional printing (of non-erasable media) mode.

In certain embodiments, an administrator interface295can be provided via network connection to the housing210. The administrator interface295can include control options directing the functions of the dual mode imaging system. In certain embodiments, the dual mode imaging system200can be configured through the administrator interface295to start up in an erasable media imaging mode or regular (non-erasable media) printing mode.

Job selection can be executed at the user interface280. Alternatively, job selection can be executed at the administrator interface295. In a third alternative, job selection can be executed at the user's personal computer print dialog box through the properties link to the print driver controls. Alternatively, the user interface280can prompt the operator to check for the proper media at the job start. The user interface280can further be responsive to the sensor225and the sensor225can be responsive to input at the user interface280.

FIGS. 3A and 3Bdepict exemplary internal architecture300in accordance with the present teachings. The internal architecture300can be provided to selectively heat, cool, and image one of erasable media and non-erasable media within the dual mode imaging device200. Effective erasable media imaging and erase requires the erasable media to be heated to a specified temperature during the writing process. The erase step requires the erasable media to be heated to an even higher temperature. In small office devices, it can be extremely important to have a simple and effective design in order to minimize the base product cost and energy usage.

The internal architecture300can provide localized heating of an erasable media as part of a write operation. It should be readily apparent to one of ordinary skill in the art that the internal architecture300depicted inFIGS. 3A and 3Brepresents generalized schematic illustrations and that other components can be added or existing components can be removed or modified.

Current versions of erasable media, particularly that utilizing UV writing on erasable photochromic media, require heating the erasable medium. Heating can be to a temperature between about 55° C. to about 80° C. Heating can further be to a temperature between about 60° C. to about 70° C. For example, heating can be to a temperature of about 65° C. Exemplary architecture herein can maintain the erasable media at a desired temperature without wasting energy.

As shown inFIGS. 3A and 3B, the internal architecture300can include a media feed320, a media drive wheel370, a media guide baffle324, a temperature management subsystem350, and a media support guide380. The media guide baffle324can further include a heat source326incorporated therein. The media support guide380can also include each of a heating device382and a cooling device384incorporated therein or adjacent thereto. Imaging devices340/360can be positioned at a discharge of a transported medium from the drive wheel370. The imaging device340can include an erasable media imaging system and the imaging device360can include a conventional imaging system. Conventional imaging systems can include ink jet imaging systems. Ink jet imaging systems can include aqueous ink jet, solid ink jet, and gel ink jet.

In general, erasable and non-erasable media can be supplied to the temperature management subsystem350at the media feed320and transported by the media drive wheel370to the media support guide380. The guide baffle324can be positioned to oppose a surface of the media not in contact with the drive wheel370. It will be appreciated that use of the term media herein can include at least one of erasable media (including an erased or original erasable media) and non-erasable paper.

In embodiments, the media feed320can include any known media feed or input suitable for supplying media to dual mode imaging device200. By way of example, the media feed320can include one or more input trays. The media feed320can include take-up rollers322in connection with the input tray. Multiple media feeds320can be utilized according to a type of media input into the dual mode imaging device200.

In embodiments, the drive wheel370can include one or more wheels for transporting the media from the feed320to the support guide380. The drive wheel370can be activated and rotated by internal mechanisms and powered by a motor “M” as known in the art. The drive wheel370can transport media in a predetermined path from feed to imaging, and ultimately to an output. The output can be internal to the dual mode imaging device200, and the output can external to the dual mode imaging device200.

In embodiments, the guide baffle324can substantially correspond in shape to an outer peripheral surface of the drive wheel370. For example, the guide baffle324can be arcuate in shape. The guide baffle324can be of a length to span a predetermined surface of the drive wheel370. In certain embodiments, the guide baffle324can be of a length to encompass a full length of a media transported by the drive wheel370. However, other lengths of the guide baffle324are considered as being within the scope of this disclosure. It will be appreciated that while the guide baffle324is depicted as arcuate, any suitable configuration can be envisioned, according to an end imaging device. For example, the guide baffle324can be substantially flat to correspond to belt feeding of media as known in the art.

As depicted, a heat source326can be provided in connection with the guide baffle324. In certain embodiments, the heat source326can include heater elements formed within the guide baffle324. For example, the heater elements of the heat source324can include resistive heating elements. The heat source326can include one or more layers of heat imparting material formed on one or more of an inner surface and an outer surface of the guide baffle324(FIG. 3B). Although the heat source326is depicted as being formed on the inner surface of the guide baffle324, it will be appreciated that the heat source326can be formed on an outer surface of the guide baffle324without intending to limit the scope of the invention.

The heat source326, as formed on an inner or outer surface of the baffle324, can include heat tape, such as a resistive heat tape, or a heat pad such as that manufactured by OEM Heaters. It will be appreciated that the heat source326can cover part or an entirety of the guide baffle324, whether internally, on the inner surface, or on the outer surface thereof. In embodiments, the heat source324can be localized to provide localized heating of the substrate as part of a write operation on erasable media as will be described further.

The guide baffle324can be spaced apart from the drive wheel370by a predetermined and constant spacing. The guide baffle324can be spaced a distance to accommodate the heat source326provided thereon, and thereby space the heat source326from media transported on the drive wheel370. As such, the heat source326can be positioned to heat the erasable media without damaging the media. It will be appreciated that the guide baffle324and hence heat source326can be positioned to effect any desired proximity to the drive wheel370without contacting the media being transported by the drive wheel370. The heat source326can be of a dimension to heat all or a portion of the erasable media transported by the drive wheel370. The heat source326can be of an intensity to heat the erasable media throughout a thickness of the erasable media. The heat source326can further be of an intensity to heat only that surface of the erasable media exposed to the heat source326.

In embodiments, and shown by way of example inFIG. 3B, an insulative material328can be provided on an external surface of the guide baffle324. The insulative material328can be formed to overlay or encompass any heat source formed on the external surface of the guide baffle324. Insulation can minimize heat loss and improve temperature control in connection with the heat source326and guide baffle324. The insulative material328can include one or more layers of air, low thermal conductivity foam, polystyrene foam, and the like.

In embodiments, the support guide380can be positioned at a dispatch point (region) where the erasable medium is released from the drive wheel370. The support guide388can be of a length to accommodate a part or an entirety of the erasable medium released from the drive wheel370according to a configuration of the dual mode imaging device200. In general, the support guide380can maintain the erasable medium flat during imaging of or writing on the medium, typically by providing a substantially flat support surface. The support guide380can further include a support guide heat source382incorporated therein. The support guide heat source382can include at least one of an internal and external heat source. The internal heat source can include resistive or similar internal heater, powered by the dual mode imaging device or otherwise. The external heat source can include, for example, a heat pad positioned on a surface of the support guide380facing imaging systems340and360. The support guide heat source382can maintain a correct temperature of an erasable medium during exposure by the translating erasable media write system340.

The support guide380can also include a cooling device384incorporated therein or adjacent thereto. In embodiments, the cooling device384can be positioned internal to the support guide380. Likewise, the cooling device384can be positioned external to the support guide380. The cooling device384can be positioned proximate a trailing end (as determined by a media transport) of the support guide380, including above, below, or above and below the trailing end of the support guide380. As such, cooling air can lower a temperature of an imaged erasable medium immediately subsequent to imaging by the erasable media write system340, thereby maintaining a maximum possible optical density of an imaged erasable medium. In embodiments, the cooling air can limit the temperature of possible touch points on imaged erasable medium.

The cooling device384can include active cooling of erasable media. In an active cooling, the cooling device384can direct a flow of cooling medium, such as cold air, onto an imaged erasable media. Active cooling can take place for a period of time and temperature suitable to reduce a temperature of the imaged erasable media to an ambient or other temperature. Ambient temperature can include a temperature below an imaging temperature. For example, ambient temperature can include room temperature. Further, active cooling can take place for a period of time and at a temperature suitable to reduce the temperature of the imaged erasable media to a UV imaging temperature. In certain embodiments, the cooling device384can include a fan. In certain embodiments, the cooling device384can include cold plates, rollers, condensers, and similar cooling apparatus acting on or adjacent to the imaged erasable media.

The described heating and cooling architecture can also minimize heat generated internally of the dual mode imaging device200, and allow for a conventional ink jet printing system to be incorporated into the dual mode imaging device200. Specifically, the conventional ink jet printing system360can be incorporated into the same housing as the erasable media write system340.

It will be appreciated that the temperature management subsystem350can be utilized to generate heat which can dry an ink deposited on a surface of a conventional non-erasable medium. More specifically, support guide heat source382can generate an amount of heat sufficient to dry a conventional ink. Even further, it will be appreciated that the support guide cooling device384can be utilized to cool a heated non-erasable medium.

FIG. 4depicts an exemplary dual mode imaging system400incorporating each of a solid ink printer and an erasable media write system in accordance with the present teachings. It should be readily apparent to one of ordinary skill in the art that the dual mode imaging system400depicted inFIG. 4represents a generalized schematic illustration and that other components can be added or existing components can be removed or modified.

As shown inFIG. 4, an internal configuration of an alternative dual mode imaging system400can include conventional imaging components and an erasable media write device460. The conventional imaging components can include solid ink imaging components such as a full width solid ink print head440, an intermediate transfer drum442, a drum cleaner444, a pressure roller446, a controller490and a memory492. A heater450can be provided in advance of the pressure roller446and operable as a media transport device in connection with each of the conventional imaging components and the erasable media write device460as will be further described. One of an erasable media and a non-erasable media420can pass through the configuration, including the media transport device, in the direction of arrow421as shown.

The memory492can include, for example, any appropriate combination of alterable, volatile or non-volatile memory, or non-alterable or fixed memory. The alterable memory, whether volatile or non-volatile, can be implemented using any one or more of static or dynamic RAM, a floppy disk and disk drive, a writeable or re-writeable optical disk and disk drive, a hard drive, flash memory or the like. Similarly, the non-alterable or fixed memory can be implemented using any one or more of ROM, PROM, EPROM, EEPROM, an optical ROM, such as CD-ROM or DVD-ROM disk, and disk drive or the like. It should also be appreciated that the controller490and/or memory492may be a combination of a number of component controllers or memories all or part of which may be located outside the printer400.

When configured to print an ink image on the intermediate transfer drum442, the one or more print heads within the full width print head440, under control of the controller490, is positioned in close proximity to the intermediate transfer drum442. As a result, under control of the controller490, the full width print head440ejects ink droplets onto the intermediate transfer drum to form ink images thereon. While ink droplets are being deposited on the intermediate transfer drum442, the pressure roller446is not in contact with the intermediate transfer drum442.

Once an image or images have been printed on the intermediate transfer drum442, according to either of a known single pass method or multi-pass method and under control of the controller490, the solid ink jet printer400converts to a configuration for transferring and fixing the image or images from the intermediate transfer drum442onto the non-erasable medium420. According to this configuration, non-erasable medium420is transported to a position between the movable or positionable transfixing roller446and intermediate transfer drum442, as indicated by arrow421. The transfixing roller446applies pressure against the back side of the non-erasable medium420in order to press the front side of the non-erasable medium against the intermediate transfer drum442. The transfixing roller446can be heated to aid in transfixing the image to the non-erasable medium.

In addition, heater450can be positioned along the feed path in advance of the transfixing roller446. The heater450can be, for example, configured as a plate. The heater plate can include resistors formed therein, heat tape formed on one or more surfaces of the heater. The heater450can generate a temperature suitable for heating either an erasable medium or non-erasable medium passing thereover, as required by a function of the dual mode imaging device400. For example, the heater plate450can preheat a non-erasable medium420to aid in transfixing the image thereto. The pressure created by the transfixing roll446on the back side of the heated non-erasable medium420facilitates the transfixing (transfer and fusing) of the image from the intermediate transfer drum442onto the non-erasable medium420.

Further, the heater450can preheat an erasable medium420to a temperature suitable for imaging by the erasable media write device460.

In certain embodiments, the erasable media write device460can include imaging components suitable for imaging erasable media. For example, the erasable media write device460can UV image an erasable media once the erasable media reaches a predetermined temperature. An exemplary UV imaging temperature of an erasable media can be from about 50° C. to about 80° C. A UV imaging temperature can further be from about 60° C. to about 70° C. The UV imaging temperature can be about 65° C. Other UV, IR or similar imaging temperatures can be set according to a type of erasable media and such imaging temperatures are intended to be included within the scope of the invention.

In embodiments, the erasable media write device460can include the heater450as the heat source. The heater450can heat the erasable medium to a temperature suitable for imaging, for example, UV imaging.

The rotation or rolling of both the intermediate transfer drum442and transfixing roll446, as shown by arrows442,447, respectively, not only transfix the images onto the non-erasable medium420, but also assist in transporting the medium between them.

Once an image is transferred from the intermediate transfer drum442and transfixed to a medium420, the transfixing roll446is moved away from the intermediate transfer drum442and the intermediate transfer drum442continues to rotate and, under the control of the controller490, any residual ink left on the intermediate transfer drum442is removed by well known drum maintenance procedures at a maintenance station, such as drum cleaner444.

The image deposited or otherwise formed on the medium can include text and/or graphic images, the creation of which is controlled by controller490. A user interface480can be included in the imaging device. The user interface480can include control components, responsive to user input, for directing the functions of the dual mode imaging system400. In certain embodiments, the dual mode imaging system400can be configured through the user interface480to start up in an erasable media imaging mode or conventional printing (of non-erasable media) mode.

Job selection can be executed at the user interface480. Alternatively, job selection can be executed at the user's personal computer print dialog box through the properties link to the print driver controls. Alternatively, the user interface480can prompt the operator to check for the proper media at the job start.