Patent Publication Number: US-2010110508-A1

Title: Printing apparatus having common scanning and printing feed path

Description:
BACKGROUND 
     Disclosed are printing apparatus having a common scanning and printing feed path. 
     In a typical printing apparatus, media such as paper will be stored in a tray or trays. When printing occurs, typically the paper will be pulled from the tray and fed through a printing feed path. Typically the paper will be driven through the printing feed path by rollers such as drive rollers. Where the printer is an electrophotographic printer, the rollers will drive the paper along the printing feed path to printing elements such as a photoreceptor, fuser, and the like. Where the printer is an ink jet printer, the drive rollers will drive the paper along the printing feed path to printing elements such as an inkjet printhead, a print assembly, a pressure roll, and the like. 
     Some typical printing apparatus will also include a scanning function. A typical printing apparatus with such scanning function may include a document handler for inputting pages. Such document handler typically has an input tray for inputting a media sheet, and has a scanning feed path through which the media sheet is fed past a scanning device, such as a full width scanning array, and typically to an output tray. 
     These printing apparatus with scanning and printing functionality thus typically include two separate subassemblies, one including the printing feed path and associated elements, and another including the scanning feed path and associated elements. The use of two such subassemblies and associated elements requires extra space and makes the printing/scanning device large. 
     SUMMARY 
     According to aspects of the embodiments, there is provided an apparatus including a media feed tray holding media to be printed, a media printing feed path along which the media to be printed are fed from the media feed tray, a scanner feed tray holding media to be scanned, and a scanner feed path along which the media to be scanned are fed from the scanner feed tray, wherein the scanner feed path overlaps with at least a portion of the media printing feed path, and a corresponding method. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a schematic view of an electrophotographic apparatus. 
         FIG. 2  illustrates a diagram of a printing apparatus. 
         FIG. 3  illustrates a diagram of a printing apparatus. 
     
    
    
     DETAILED DESCRIPTION 
     While the present invention will be described in connection with preferred embodiments thereof, it will be understood that it is not intended to limit the invention to that embodiment. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. 
     The embodiments include a printing apparatus, including a media feed tray holding media to be printed, a media printing feed path along which the media to be printed are fed from the media feed tray, a scanner feed tray holding media to be scanned, and a scanner feed path along which the media to be scanned are fed from the scanner feed tray, wherein the scanner feed path overlaps with at least a portion of the media printing feed path. 
     The embodiments further include an image production apparatus, that includes a printing feed path along which media to be printed is fed, the printing feed path for directing the media to be printed to a scanning device, a photoreceptor and a fuser, and a scanning feed path along which media to be scanned is fed, the scanning feed path overlapping with a portion of the media feed path, the scanning feed path for directing media to be scanned to the scanning device. 
     The embodiments further include a method of controlling operations in a printing apparatus. The method includes directing media to be printed from a media feed tray along a printing feed path, directing media to be scanned along a scanner feed path to a scanning device, wherein the scanner feed path overlaps with at least a portion of the printing feed path. 
     In as much as the art of electrophotographic printing is well known, the various processing stations employed in the  FIG. 1  printing machine will be shown schematically and their operation described briefly with reference thereto. Various other printing machines could also be used including an inkjet or other type of printer, and this is only an example of a particular printing machine that may be used with the invention. 
       FIG. 1  is a partial schematic view of a digital imaging system, such as the digital imaging system of U.S. Pat. No. 6,505,832, which is hereby incorporated by reference. The imaging system is used to produce an image such as a color image output in a single pass of a photoreceptor belt. It will be understood, however, that it is not intended to limit the invention to the embodiment disclosed. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims, including a multiple pass color process system, a single or multiple pass highlight color system, and a black and white printing system. 
     Referring to  FIG. 1 , an Output Management System  660  may supply printing jobs to the Print Controller  630 . Printing jobs may be submitted from the Output Management System Client  650  to the Output Management System  660 . A pixel counter  670  is incorporated into the Output Management System  660  to count the number of pixels to be imaged with toner on each sheet or page of the job, for each color. The pixel count information is stored in the Output Management System memory. The Output Management System  660  submits job control information, including the pixel count data, and the printing job to the Print Controller  630 . Job control information, including the pixel count data, and digital image data are communicated from the Print Controller  630  to the Controller  490 . 
     The printing system preferably uses a charge retentive surface in the form of an Active Matrix (AMAT) photoreceptor belt  410  supported for movement in the direction indicated by arrow  412 , for advancing sequentially through the various xerographic process stations. The belt is entrained about a drive roller  414 , tension roller  416  and fixed roller  418  and the drive roller  414  is operatively connected to a drive motor  420  for effecting movement of the belt through the xerographic stations. A portion of photoreceptor belt  410  passes through charging station A where a corona generating device, indicated generally by the reference numeral  422 , charges the photoconductive surface of photoreceptor belt  410  to a relatively high, substantially uniform, preferably negative potential. 
     Next, the charged portion of photoconductive surface is advanced through an imaging/exposure station B. At imaging/exposure station B, a controller, indicated generally by reference numeral  490 , receives the image signals from Print Controller  630  representing the desired output image and processes these signals to convert them to signals transmitted to a laser based output scanning device, which causes the charge retentive surface to be discharged in accordance with the output from the scanning device. Preferably the scanning device is a laser Raster Output Scanner (ROS)  424 . Alternatively, the ROS  424  could be replaced by other xerographic exposure devices such as LED arrays. 
     The photoreceptor belt  410 , which is initially charged to a voltage V 0 , undergoes dark decay to a level equal to about −500 volts. When exposed at the exposure station B, it is discharged to a level equal to about −50 volts. Thus after exposure, the photoreceptor belt  410  contains a monopolar voltage profile of high and low voltages, the former corresponding to charged areas and the latter corresponding to discharged or developed areas. 
     At a first development station C, developer structure, indicated generally by the reference numeral  432  utilizing a hybrid development system, the developer roller, better known as the donor roller, is powered by two developer fields (potentials across an air gap). The first field is the AC field which is used for toner cloud generation. The second field is the DC developer field which is used to control the amount of developed toner mass on the photoreceptor belt  410 . The toner cloud causes charged toner particles to be attracted to the electrostatic latent image. Appropriate developer biasing is accomplished via a power supply. This type of system is a noncontact type in which only toner particles (black, for example) are attracted to the latent image and there is no mechanical contact between the photoreceptor belt  410  and a toner delivery device to disturb a previously developed, but unfixed, image. A toner concentration sensor  200  senses the toner concentration in the developer structure  432 . 
     The developed but unfixed image is then transported past a second charging device  436  where the photoreceptor belt  410  and previously developed toner image areas are recharged to a predetermined level. 
     A second exposure/imaging is performed by device  438  which comprises a laser based output structure which is utilized for selectively discharging the photoreceptor belt  410  on toned areas and/or bare areas, pursuant to the image to be developed with the second color toner. At this point, the photoreceptor belt  410  contains toned and untoned areas at relatively high voltage levels, and toned and untoned areas at relatively low voltage levels. These low voltage areas represent image areas which are developed using discharged area development (DAD). To this end, a negatively charged, developer material  440  comprising color toner is employed. The toner, which by way of example may be yellow, is contained in a developer housing structure  442  disposed at a second developer station D and is presented to the latent images on the photoreceptor belt  410  by way of a second developer system. A power supply (not shown) serves to electrically bias the developer structure to a level effective to develop the discharged image areas with negatively charged yellow toner particles. Further, a toner concentration sensor  200  senses the toner concentration in the developer housing structure  442 . 
     The above procedure is repeated for a third image for a third suitable color toner such as magenta (station E) and for a fourth image and suitable color toner such as cyan (station F). The exposure control scheme described below may be utilized for these subsequent imaging steps. In this manner a full color composite toner image is developed on the photoreceptor belt  410 . In addition, a mass sensor  110  measures developed mass per unit area. Although only one mass sensor  110  is shown in  FIG. 1 , there may be more than one mass sensor  110 . 
     To the extent to which some toner charge is totally neutralized, or the polarity reversed, thereby causing the composite image developed on the photoreceptor belt  410  to consist of both positive and negative toner, a negative pre-transfer dicorotron member  450  is provided to condition the toner for effective transfer to a substrate using positive corona discharge. 
     Subsequent to image development a sheet of support material  452  is moved into contact with the toner images at transfer station G. The sheet of support material  452  is advanced to transfer station G by a sheet feeding apparatus  500 , described in detail below. The sheet of support material  452  is then brought into contact with photoconductive surface of photoreceptor belt  410  in a timed sequence so that the toner powder image developed thereon contacts the advancing sheet of support material  452  at transfer station G. 
     Transfer station G includes a transfer dicorotron  454  which sprays positive ions onto the backside of sheet  452 . This attracts the negatively charged toner powder images from the photoreceptor belt  410  to sheet  452 . A detack dicorotron  456  is provided for facilitating stripping of the sheets from the photoreceptor belt  410 . 
     After transfer, the sheet of support material  452  continues to move, in the direction of arrow  458 , onto a conveyor  600  which advances the sheet to fusing station H. Fusing station H includes a fuser assembly, indicated generally by the reference numeral  460 , which permanently affixes the transferred powder image to sheet  452 . Preferably, fuser assembly  460  comprises a heated fuser roller  462  and a backup or pressure roller  464 . Sheet  452  passes between fuser roller  462  and pressure roller  464  with the toner powder image contacting fuser roller  462 . In this manner, the toner powder images are permanently affixed to sheet  452 . After fusing, a chute, not shown, guides the advancing sheet  452  to a catch tray, stacker, finisher or other output device (not shown), for subsequent removal from the printing machine by the operator. The fuser assembly  460  may be contained within a cassette, and may include additional elements not shown in this figure, such as an endless fuser belt or endless fuser web (not the fuser cleaner web) around the fuser roller  462 . In typical printing machines, this belt or web has been kept relatively short to minimize the size of the fuser assembly or cassette. 
     After the sheet of support material  452  is separated from photoconductive surface of photoreceptor belt  410 , the residual toner particles carried by the non-image areas on the photoconductive surface are removed therefrom. These particles are removed at cleaning station I using a cleaning brush or plural brush structure contained in a housing  466 . The cleaning brushes  468  are engaged after the composite toner image is transferred to a sheet. 
     Controller  490  regulates the various printer functions. The controller  490  is preferably a programmable controller, which controls printer functions hereinbefore described. The controller  490  may provide a comparison count of the copy sheets, the number of documents being recirculated, the number of copy sheets selected by the operator, time delays, jam corrections, etc. The control of all of the exemplary systems heretofore described may be accomplished by conventional control switch inputs from the printing machine consoles selected by an operator. Conventional sheet path sensors or switches may be utilized to keep track of the position of the document and the copy sheets. 
     The foregoing description illustrates the general operation of an electrophotographic printing machine incorporating the fuser apparatus of the present disclosure therein. Not all of the elements discussed in conjunction with  FIG. 1  are necessarily needed for effective use of the invention. Instead, these elements are described as a machine within which embodiments of the invention could operate. 
       FIG. 2  illustrates a printing apparatus  210 , also known as an image production apparatus, which may be an electrophotographic apparatus, in greater detail. The printing apparatus  210  includes media trays  212 , which store media such as paper for printing or copying. Any number of media trays  212  may be used. The media may be driven from the media trays  212  along a printing feed path by drive rollers  214 , to a photoreceptor  224  and a fuser  226 , for example. After printing, the media may exit from the printing apparatus through the assembly  228  and the printing exit tray  230 . The printing apparatus  210  may include any of the elements of the  FIG. 1  digital imaging system, even though not shown in  FIG. 2 . 
     A document handler  234  may be included from which media may traverse a document handler feed path  238  to be output at document handler output tray  236 . The document handler  234  may be used for the scanning of media, for example. 
     The printing apparatus  210  may also include a scanner feed tray  316 . The scanner feed tray  316  can feed media to be scanned into the printing apparatus  210 , where it may be scanned by scanning device  218 , for example. Scanning device  218  may be a duplex scanning device, such as full-width array bars or the like. The scanning device  218  is placed within the same printing feed path as media from the media trays  212 . However, media from scanner feed tray  316  does not follow the entire printing feed path, but instead exits from the printing feed path at scanner feed path  220 , where it may be directed to the scanner output tray  222 , which may be formed as an integral part of a cover of the printing apparatus  210 . Thus, media to be scanned from the scanner feed tray  316  does not proceed to the photoreceptor  224  or to the fuser  226 . 
     The printing apparatus  310  illustrated in  FIG. 3  includes media feed trays  312 , from which media may be driven along a printing feed path by drive rollers  314 , to a photoreceptor  324  and a fuser  326 , for example. After printing, the media may exit from the printing apparatus through the assembly  328  and the printing exit tray  330 . The printing apparatus  310  may include any of the elements of  FIG. 1  digital imaging system, even though not shown in  FIG. 3 . 
     The printing apparatus  310  may also include a scanner feed tray  316 . The scanner feed tray  316  can feed media to be scanned into the printing apparatus  310 , where it may be scanned by scanning device  318 , for example. Scanning device  318  may be a duplex scanning device, such as full-width array bars or the like. The scanning device  318  is placed within the same printing feed path as media from the media trays  312 . However, media from scanner feed tray  316  does not follow the entire printing feed path, but, after being diverted by diverter gate  332 , exits from the printing feed path and continues in scanner feed path  320 , where it may be directed to the scanner output tray  322 , which may be formed as an integral part of a cover of the printing apparatus  310 . 
     In the embodiment of  FIG. 3 , the document handler  234  has been eliminated. All scanning functions can be accomplished with the scanner feed tray  316  and the scanning device  318 . Typical printing apparatus that include a scanning function often include such a document handler which can be bulky and increase the cost of production. Elimination of the document handler  234  saves space and eliminates separate feed paths. By sharing the feed path for scanning and printing, space is saved, cost is reduced, and the printing apparatus may be more compact. 
     The controller  490  of  FIG. 1  may have instructions loaded via a computer readable medium. The embodiments may include computer-readable medium for carrying or having computer-executable instructions or data structures stored thereon. Such computer-readable medium can be any available medium that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, such computer-readable medium can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code means in the form of computer-executable instructions or data structures. When information is transferred or provided over a network or another communications connection (either hard wired, wireless, or combination thereof to a computer, the computer properly views the connection as a computer-readable medium. Thus, any such connection is properly termed a computer-readable medium. Combinations of the above should also be included within the scope of the computer-readable medium. 
     Computer-executable instructions include, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing device to perform a certain function or group of functions. Computer-executable instructions also include program modules that are executed by computers in stand-alone or network environments. Generally, program modules include routines, programs, objects, components, and data structures, and the like that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of the program code means for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described therein. The instructions for carrying out the functionality of the disclosed embodiments may be stored on such a computer-readable medium. 
     It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.