Electrostatographic reproduction machine having a motion-defect-free cleaning method and assembly

Information

  • Patent Grant
  • 6430387
  • Patent Number
    6,430,387
  • Date Filed
    Wednesday, December 20, 2000
    23 years ago
  • Date Issued
    Tuesday, August 6, 2002
    21 years ago
Abstract
A motion-defect-free assembly and a method of minimizing cleaning apparatus induced motion quality disturbances in a moving belt photoreceptor of a toner image reproduction machine are provided. The assembly for practicing the method includes at least one resilient member located to each side of the moving belt photoreceptor at a desired belt cleaning station along a path of movement of the belt photoreceptor, and a cleaning apparatus that is mounted at the cleaning station and that includes at least one separately moveable cleaning member. The cleaning apparatus also includes a moveable frame having frame locating members, and the at least one separately moveable cleaning member. The motion-defect-free assembly also includes a drive and control system for first moving the moveable frame into contact with each of the locating members and for then separately moving, relative to the moveable frame, the at least one separately moveable cleaning member into contact and cleaning engagement with the moving belt photoreceptor, thereby minimizing cleaning apparatus induced motion quality disturbances in the moving belt photoreceptor.
Description




BACKGROUND OF THE INVENTION




This invention relates generally to electrostatographic image reproduction machines, and more particularly concerns an electrostatographic reproduction machine having a motion-defect-free cleaning method and assembly for preventing motion related image defects.




In an electrostatographic image reproduction machine, a photoconductive member is charged to a substantially uniform potential to sensitize the surface thereof. The charged portion of the photoconductive member is exposed to a light image of an original document being reproduced. Exposure of the charged photoconductive member selectively dissipates the charge thereon in irradiated areas. This records an electrostatic latent image on the photoconductive member corresponding to the informational areas contained within the original document being reproduced.




After the electrostatic latent image is recorded on the photoconductive member, the latent image is developed by bringing developer material containing charged toner particles, for example, black toner particles, into contact therewith. Developer material can be single component comprised only of charged toner particles, or it may be dual component comprising carrier particles and toner particles that are triboelectrically charged when admixed or mixed with the carrier particles. In either case, bringing the developer material into contact with the latent image forms a toner image on the photoconductive member which is subsequently transferred to a copy sheet. The copy sheet is then separated from the photoconductive member and the toner powder is fed on the copy sheet through a fusing apparatus where it is heated to permanently affix it to the copy sheet, thus forming a black and white copy of the original document.




Multi-color electrostatographic image reproduction machines which use multi-colored toners are substantially identical in each color image forming process to the foregoing process of black and white image reproduction which uses only black toner. However, rather than forming a single latent image on the photoconductive member, several single color latent images corresponding to color separated light images of the original document are recorded thereon. Each single color electrostatic latent image is developed with toner particles of a color complementary thereto. This process may be performed in a single pass of the photoconductive member, or in multipasses thereof during which image formation is repeated over a plurality of cycles, for forming different colored images using their respective complementarily colored toner particles. Each single color toner powder image is thus formed on the photoconductive member in superimposed registration with the other toner powder images.




This creates a composite multi-layered toner powder image which is then transferred directly, or via an intermediate transfer member, onto a copy sheet. The copy sheet is then separated from the photoconductive member or from the intermediate transfer member and fed through a fusing apparatus for permanently affixing the toner image to the copy sheet. This creates a hard color copy of the original multi-color document.




In multipass multi-color image reproduction machines which have a photoconductive belt member, it is necessary for the cleaning system therein to be capable of engaging the photoconductive member to clean, as well as, retracting from the photoconductive member in order to allow image formation. In order to sustain a desired machine output rate, it is also necessary for the cleaning system to be accurately locatable “on the fly”.




Unfortunately, there is a major problem that results from motion quality disturbances as a retracted cleaner re-engages the photoconductive member “on the fly”. It has been found that conventional cleaning systems, such as brush cleaners with supporting frames that directly contact a photoconductor assembly itself, ordinarily cannot be located accurately for cleaning without the motion of such frames having an undesirable impact on the photoconductive member or photoreceptor, and thereby causing motion related defects or image disturbance defects. Conventional attempts to reduce such impact by reducing the speed of the cleaning housing or frame at contact, ordinarily result in unacceptably high levels of impact force.




There is therefore a need for a cleaning system that will solve such motion quality impact problems.




SUMMARY OF THE INVENTION




In accordance with one aspect of the present invention, there is provided a motion-defect-free method of minimizing cleaning apparatus induced motion quality disturbances in a moving belt photoreceptor of a toner image reproduction. The method includes the steps of providing at least one resilient member to each side of the moving belt photoreceptor and at a desired belt cleaning station along a path of movement of the belt photoreceptor, and mounting a cleaning apparatus that includes a moveable frame having frame locating members, and at least one separately moveable cleaning member at the cleaning station. The motion-defect-free method also includes the steps of first moving the moveable frame into contact with each of the locating members, and for then separately moving, relative to the moveable frame, the at least one separately moveable cleaning member, into contact and cleaning engagement with the moving belt photoreceptor, thereby minimizing cleaning apparatus induced motion quality disturbances in the moving belt photoreceptor.




In accordance with another aspect of the present invention, there is provided a motion-defect-free cleaning assembly for minimizing cleaning apparatus induced motion quality disturbances in a moving belt photoreceptor of a toner image reproduction. The assembly includes at least one resilient member located to each side of the moving belt photoreceptor at a desired belt cleaning station along a path of movement of the belt photoreceptor, and a cleaning apparatus that is mounted at the cleaning station and that includes at least one separately moveable cleaning member and a moveable frame having frame locating members. The motion-defect-free assembly also includes a drive and control system for first moving the moveable frame into contact with each of the locating members and for then separately moving, relative to the moveable frame, the at least one separately moveable cleaning member into contact and cleaning engagement with the moving belt photoreceptor, thereby minimizing cleaning apparatus induced motion quality disturbances in the moving belt photoreceptor.











BRIEF DESCRIPTION OF THE DRAWINGS




In the detailed description of the invention presented below, reference is made to drawings, in which:





FIG. 1

is a schematic illustration of an exemplary electrostatographic reproduction machine incorporating a dual mode development unit operating time control apparatus and method in accordance with the present invention;





FIG. 2

is a schematic illustration of the motion-defect-free cleaning apparatus of the present invention in a retracted position; and





FIG. 3

is a schematic illustration of the motion-defect-free cleaning apparatus of the present invention in an engaged and cleaning position.











DETAILED DESCRIPTION OF THE INVENTION




For a general understanding of the features of the present invention, reference is made to the drawings, wherein like reference numerals have been used throughout to identify the same or similar elements. On the contrary, the following description 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.




Referring to

FIG. 1

, there is depicted an exemplary electrostatographic reproduction machine, such as a multipass color electrostatographic reproduction machine


8


. As is well known, the color copy process typically involves a computer generated color image which may be conveyed to an image processor


136


, or alternatively a color document


72


which may be placed on the surface of a transparent platen


73


. A scanning assembly


124


, having a light source


74


illuminates the color document


72


. The light reflected from document


72


is reflected by mirrors


75


,


76


, and


77


, through lenses (not shown) and a dichroic prism


78


to three charged-coupled linear photosensing devices (CCDs)


79


where the information is read. Each CCD


79


outputs a digital image signal the level of which is proportional to the intensity of the incident light.




The digital signals represent each pixel and are indicative of blue, green, and red densities. They are conveyed to the IPU


136


where they are converted into color separations and bit maps, typically representing yellow, cyan, magenta, and black. IPU


136


stores the bit maps for further instructions from an electronic subsystem (ESS)


80


including the apparatus and method for dual mode control of the operating or “on” time for the development units of the machine


8


(to be described in detail below).




The ESS


80


is preferably a self-contained, dedicated minicomputer having a central processor unit (CPU), electronic storage, and a display or user interface (UI). The ESS is the control system which, with the help of sensors and connections


80


B as well as a pixel counter


80


A, reads, captures, prepares and manages the image data flow between IPU


136


and scanning assembly


124


. In addition, the ESS


80


is the main multi-tasking processor for operating and controlling all of the other machine subsystems and printing operations. These operations include imaging, development, sheet delivery and transfer, and cleaning using the cleaning method and assembly


200


in accordance with the present invention. Such operations also include various functions associated with subsequent finishing processes. Some or all of these subsystems may have micro-controllers that communicate with the ESS


80


.




The multipass color electrostatographic reproduction machine


8


employs a photoreceptor


10


in the form of a belt having a photoconductive surface


11


on an electroconductive substrate, and a backside


13


. Preferably the surface


11


is made from an organic photoconductive material, although numerous photoconductive surfaces and conductive substrates may be employed. The belt


10


is driven by means of motor


20


having an encoder attached thereto (not shown) to generate a machine timing clock. Photoreceptor


10


moves along a path defined by rollers


14


,


18


, and


16


in a counter-clockwise direction as shown by arrow


12


.




Initially, in a first imaging pass, the photoreceptor


10


passes through charging station AA where a corona generating devices, indicated generally by the reference numeral


22


,


23


, on the first pass, charge photoreceptor


10


to a relatively high, substantially-uniform potential. Next, in this first imaging pass, the charged portion of photoreceptor


10


is advanced through an imaging station BB. At imaging station BB, the uniformly charged belt


10


is exposed to the scanning device


24


forming a latent image by causing the photoreceptor to be discharged in accordance with one of the color separations and bit map outputs from the scanning device


24


, for example black. The scanning device


24


is a laser Raster Output Scanner (ROS). The ROS creates the first color separation image in a series of parallel scan lines having a certain resolution, generally referred to as lines per inch. Scanning device


24


may include a laser with rotating polygon mirror blocks and a suitable modulator, or in lieu-thereof, a light emitting diode array (LED) write bar positioned adjacent the photoreceptor


10


.




At a first development station CC, a non-interactive development unit, indicated generally by the reference numeral


26


, advances developer material


31


containing carrier particles and charged toner particles at a desired and controlled concentration into contact with a donor roll, and the donor roll then advances charged toner particles into contact with the latent image and any latent target marks. Development unit


26


may have a plurality of magnetic brush and donor roller members, plus rotating augers or other means for mixing toner and developer. A special feature of non-interactive development is that adding and admixing can continue even when development is disabled. Therefore the timing algorithm for the adding and admixing function can be independent of that for the development function, as long as admixing is enabled whenever development is required.




These donor roller members transport negatively charged black toner particles for example, to the latent image for development thereof which tones the particular (first) color separation image areas and leaves other areas untoned. Power supply


32


electrically biases development unit


26


. Development or application of the charged toner particles as above typically depletes the level and hence concentration of toner particles, at some rate, from developer material in the development unit


26


. This is also true of the other development units (to be described below) of the machine


8


.




Accordingly, different jobs of several documents being reproduced, will cause toner depletion at different rates depending on the sustained, copy sheet area toner coverage level of the images thereof being reproduced. In a machine using two component developer material as here, such depletion undesirably changes the concentration of such particles in the developer material. In order to maintain the concentration of toner particles within the developer material (in an attempt to insure the continued quality of subsequent images), the adding and admixing function of the development unit must be operating or turned “on” for some controlled period of time in order for the device


127


to replenish the development unit


26


with fresh toner particles from a source


129


. Such fresh toner particles must then be admixed with the carrier particles in order to properly charge them triboeletrically.




On the second and subsequent passes of the multipass machine


8


, the pair of corona generating devices


22


and


23


are employed for recharging and adjusting the voltage level of both the toned (from the previous imaging pass), and untoned areas on photoreceptor


10


to a substantially uniform level. A power supply is coupled to each of the electrodes of corona generating devices


22


and


23


. Corona generating devices


22


and


23


substantially eliminate any voltage difference between toned areas and bare untoned areas, as well as to reduce the level of residual charge remaining on the previously toned areas, so that subsequent development of different color separation toner images is effected across a uniform development field.




Scanning device


24


is then used on the second and subsequent passes of the multipass machine


8


, to superimpose subsequent latent images of a particular color separation image, by selectively discharging the recharged photoreceptor


10


. The operation of scanning device


24


is of course controlled by the controller, ESS


80


. One skilled in the art will recognize that those areas developed or previously toned with black toner particles will not be subjected to sufficient light from the scanning device


24


as to discharge the photoreceptor region lying below such black toner particles. However, this is of no concern as there is little likelihood of a need to deposit other colors over the black regions or toned areas.




Thus on a second pass, scanning device


24


records a second electrostatic latent image on recharged photoreceptor


10


. Of the four development units, only the second development unit


42


, disposed at a second developer station EE, has its development function turned “on” (and the rest turned “off”) for developing or toning this second latent image. As shown, the second development unit


42


contains negatively charged developer material


40


, for example, one including yellow toner. The toner


40


contained in the development unit


42


is thus transported by a donor roll to the second latent image recorded on the photoreceptor


10


, thus forming additional toned areas of the particular color separation on the photoreceptor


10


. A power supply (not shown) electrically biases the development unit


42


to develop this second latent image with the negatively charged yellow developer material


40


. As will be further appreciated by those skilled in the art, the yellow colorant is deposited immediately subsequent to the black so that further colors that are additive to yellow, and interact therewith to produce the available color gamut, can be exposed through the yellow toner layer.




On the third pass of the multipass machine


8


, the pair of corona generating devices


22


and


23


are again employed for recharging and readjusting the voltage level of both the toned and untoned areas on photoreceptor


10


to a substantially uniform level. A power supply is coupled to each of the electrodes of corona generating devices


22


and


23


. The corona generating devices


22


and


23


substantially eliminate any voltage difference between toned areas and bare untoned areas, as well as to reduce the level of residual charge remaining on the previously toned areas so that subsequent development of different color toner images is effected across a uniform development field. A third latent image is then again recorded on photoreceptor


10


by scanning device


24


. With the development functions of the other development units turned “off”, this image is developed in the same manner as above using a third color toner


55


contained in a development unit


57


disposed at a third developer station GG. An example of a suitable third color toner is magenta. Suitable electrical biasing of the development unit


57


is provided by a power supply, not shown.




On the fourth pass of the multipass machine


8


, the pair of corona generating devices


22


and


23


again recharge and adjust the voltage level of both the previously toned and yet untoned areas on photoreceptor


10


to a substantially uniform level. A power supply is coupled to each of the electrodes of corona generating devices


22


and


23


. The corona generating devices


22


and


23


substantially eliminate any voltage difference between toned areas and bare untoned areas as well as to reduce the level of residual charge remaining on the previously toned areas. A fourth latent image is then again created using scanning device


24


. The fourth latent image is formed on both bare areas and previously toned areas of photoreceptor


10


that are to be developed with the fourth color image. This image is developed in the same manner as above using, for example, a cyan color toner


65


contained in development unit


67


at a fourth developer station II. Suitable electrical biasing of the development unit


67


is provided by a power supply, not shown. Following the black development unit


26


, development units


42


,


57


, and


67


are preferably of the type known in the art which do not interact, or are only marginally interactive with previously developed images. For examples, a DC jumping development system, a powder cloud development system, or a sparse, non-contacting magnetic brush development system are each suitable for use in an image on image color development system as described herein. In order to condition the toner for effective transfer to a substrate, a negative pre-transfer corotron member negatively charges all toner particles to the required negative polarity to ensure proper subsequent transfer.




Since the machine


8


is a multicolor, multipass machine as described above, only one of the plurality of development units,


26


,


42


,


57


and


67


may have its development function turned “on” and operating during any one of the required number of passes, for a particular color separation image development. The remaining development units must thus have their development functions turned off. As pointed out above and to be addressed below, the conventional approach is to use the same timing for the development function and the adding and admixing function, which causes design and operating conflicts in determining and effecting a control method for the “on” time for each development unit, particularly during sustained high area toner coverage jobs, in order to insure continued reproduction of high quality images without risking a quality or productivity degradation, or customer dissatisfaction.




Still referring to

FIG. 1

, during the exposure and development of the last color separation image, for example by the fourth development unit


67


a sheet


44


of support material is advanced to a transfer station JJ by a sheet feeding apparatus


30


. During simplex operation (single sided copy), a blank sheet


44


may be fed from tray


15


or tray


17


, or a high capacity tray


45


thereunder, to a registration transport


21


, in communication with controller


81


, where the sheet


44


is registered in the process and lateral directions, and for skew position. One skilled in the art will realize that trays


15


,


17


, and


45


each hold a different sheet type. The speed of the sheet


44


is adjusted at registration transport


21


so that the sheet arrives at transfer station JJ in synchronization with the composite multicolor image on the surface of photoconductive belt


10


.




Registration transport


21


receives a sheet


44


from either a vertical transport


23


or a high capacity tray transport


25


and moves the received sheet


44


to a pretransfer baffle


27


. The vertical transport


23


receives the sheet from either tray


15


or tray


17


, or the single-sided copy from duplex tray


28


, and guides it to the registration transport


21


via a turn baffle


29


. Sheet feeders


35


and


39


respectively advance a copy sheet


44


from trays


15


and


17


to the vertical transport


23


by chutes


41


and


43


. The high capacity tray transport


25


receives the sheet


44


from tray


45


and guides it to the registration transport


21


via a lower baffle


45


. A sheet feeder


46


advances copy sheets


44


from tray


45


to transport


25


by a chute


47


.




The pretransfer baffle


27


guides the sheet


44


from the registration transport


21


to transfer station JJ. Charge limiter


49


located on pretransfer baffle


27


restricts the amount of electrostatic charge a sheet


44


can place on the baffle


27


thereby reducing image quality problems and shock hazards. The charge can be placed on the baffle from either the movement of the sheet


44


through the baffle or by the corona generating devices located at transfer station JJ. When the charge exceeds a threshold limit, charge limiter


49


discharges the excess to ground.




Transfer station JJ includes a transfer corona device


54


which provides positive ions to the backside of the copy sheet


44


. This attracts the negatively charged toner powder images from photoreceptor belt


10


to the sheet


44


. A detack corona device


56


is provided for facilitating stripping of the sheet


44


from belt


10


.




A sheet-to-image registration detector


110


is located in the gap between the transfer and detack corona devices


54


and


56


to sense variations in actual sheet


44


to image registration and provides signals indicative thereof to ESS


80


and controller


81


while the sheet


44


is still tacked to photoreceptor belt


10


. After transfer, the sheet


44


continues to move, in the direction of arrow


58


, onto a conveyor


59


that advances the sheet


44


to fusing station KK.




Fusing station KK includes a fuser assembly, indicated generally by the reference numeral


60


, which permanently fixes the transferred color image to the copy sheet


44


. Preferably, fuser assembly


60


comprises a heated fuser roller


109


and a backup or pressure roller


113


. The copy sheet


44


passes between fuser roller


109


and backup roller


113


with the toner powder image contacting fuser roller


109


. In this manner, the multi-color toner powder image is permanently fixed to the sheet


44


. After fusing, chute


66


guides the advancing sheet


44


to feeder


68


for exit to a finishing module (not shown) via output


64


. However, for duplex operation, the sheet


44


is reversed in position at inverter


70


and transported to duplex tray


28


via chute


69


. Duplex tray


28


temporarily collects sheets


44


whereby sheet feeder


33


then advances it to the vertical transport


23


via chute


34


. The sheet


44


fed from duplex tray


28


receives an image on the second side thereof, at transfer station JJ, in the same manner as the image was deposited on the first side thereof. The completed duplex copy exits to the finishing module (not shown) via output


64


.




Referring now to

FIGS. 1-3

, the multipass color electrostatographic reproduction machine


8


includes a cleaning station LL where the image bearing or photoreceptor surface


11


of the photoreceptor


10


is cleaned using the motion-defect-free cleaning method and assembly


200


of the present invention. As illustrated in

FIG. 1

, after the sheet


44


of support material is separated from photoreceptor


10


, residual toner particles remaining on the photoreceptor surface are removed in accordance with the present invention, and in preparation for subsequent use.




As discussed in the background, multi-color image reproduction machines, such as the machine


8


, which make multiple passes with the photoreceptor


10


, ordinarily require the cleaning system therein to be capable of retracting from the photoreceptor during image formation, and engaging the photoreceptor for cleaning. The locational accuracy required from these cleaning systems is such that “on the fly” locating could be employed. However, the resulting motion quality impact on the photoreceptor causes motion related defects or image disturbance defects. In other words, the cleaning system must retract during the multiple passes required for multicolor image formation. It is only after the image is transferred, that the cleaning system re-engages. A major problem which results particularly from the re-engagement, is motion quality disturbances or defects. Such systems and their method are thus not motion-defect-free, particularly where the photoreceptor is in the form of a belt.




To solve this major problem, there is provided in accordance with the present invention, a method of minimizing cleaning apparatus induced motion quality disturbances in a moving belt photoreceptor


10


of a toner image reproduction machine


8


. The method includes the steps of (i) providing at a desired belt cleaning station LL along a path of movement of the belt photoreceptor, at least one resilient member


206


,


208


to each side of the moving belt photoreceptor; (ii) mounting at the cleaning station LL, a cleaning apparatus


210


that includes at least one separately moveable cleaning member


212


,


214


, and a moveable frame


216


having frame locating members


217


,


218


and supporting the at least one separately moveable cleaning member


212


,


214


; and (iii) first moving the moveable frame


216


towards the moving belt photoreceptor


10


and towards the at least one resilient member


206


,


208


. A drive and control system (not shown) including the ESS


80


, is used in combination with the other elements of the present invention, for timing, moving and locating the frame and cleaning members of the motion-defect-free cleaning assembly


200


of the present invention.




The method also includes the steps of (iv) next contacting each of the locating members


217


,


218


of the moveable frame


216


to the at least one resilient member


206


,


208


; and (v) then separately moving, relative to the moveable frame


216


, the at least one separately moveable cleaning member


212


,


214


into cleaning contact with the moving belt photoreceptor


10


, thereby minimizing cleaning apparatus induced motion quality disturbances in the moving belt photoreceptor. The positioning step preferably comprises positioning a backer bar


202


,


204


against the backside


13


of the moving belt photoreceptor


10


, and at least one resilient or spring loaded member


206


,


208


to each side of the moving belt photoreceptor


10


. The backer bar


202


,


204


is mounted for effectively supporting a backside


13


of the moving belt photoreceptor


10


during cleaning, and as such preferably extends from one side to the other thereof.




The mounting step comprises mounting at the cleaning station LL, a cleaning apparatus that includes at least one moveable cleaning member or brush


212


,


214


, and the moveable frame


216


supporting the at least one cleaning brush. The providing step as shown preferably comprises providing at least a pair of backer bars


202


,


204


and a pair of resilient or spring loaded members


206


,


208


on each side of the belt photoreceptor


10


(only one side of the belt is visible from the drawings). The cleaning apparatus thus also includes a pair of separately moveable cleaning brushes


212


,


214


.




For carrying out the method of the present invention, a motion-defect-free cleaning assembly


200


is provided. As illustrated, the motion-defect-free cleaning assembly


200


includes at least one, and preferably a plurality of backer bars


202


,


204


for effectively supporting the backside


13


of the moving belt photoreceptor


10


during cleaning, and at least one, preferably a plurality of resilient members


206


,


208


positioned to each side of the moving belt photoreceptor


10


at the desired belt cleaning station LL. The motion-defect-free cleaning assembly


200


also includes a cleaning apparatus


210


mounted to the frame of the machine at the desired belt cleaning station LL for cleaning the image carrying surface of the belt photoreceptor


10


.




The cleaning apparatus


210


includes at least one separately moveable cleaning member, for example, cleaning brushes


212


,


214


, and the moveable frame


216


which in turn supports the cleaning brushes, a plurality of locating members


217


,


218


for first contacting and locating against the resilient members


206


,


208


prior to the cleaning brushes


212


,


214


contacting and engagingly cleaning a portion of the surface


11


of the moving belt photoreceptor


10


. As described above, each of the resilient members


206


,


208


comprises a spring member. As described above, the motion-defect-free assembly


200


includes a drive and control system (including the ESS


80


) for first moving the moveable frame


216


into contact with each of the locating members


217


,


218


and for then separately moving, relative to the moveable frame


216


, the at least one separately moveable cleaning member


212


,


214


into contact and cleaning engagement with the moving belt photoreceptor


10


, thereby minimizing cleaning apparatus induced motion quality disturbances in the moving belt photoreceptor.




When the cleaning assembly


200


is properly located for re-engagement with the moving belt photoreceptor, only the fibers of the cleaning members or brushes


212


,


214


actually contact the photoreceptor, and only after the mass and kinetic energy of the moving cleaning apparatus frame had already been absorbed by the resilient or spring loaded members


206


,


208


. The only motion related forces impacting the moving belt photoreceptor


10


from such contact and re-engagement, come from deflection of the brush fibers of the brushes


212


,


214


. This is fairly straight forward and cost effective, and importantly minimizes motion quality impacts and defects significantly.




Depending on the locational accuracy specified, pins


220


and locating holes


222


can be used or spring loaded members can be added to the moveable frame


216


of the cleaning apparatus


210


. By first locating the cleaning apparatus frame or moveable frame


216


to resilient members


206


,


208


of the machine frame, and then contacting the moving belt photoreceptor


10


only with the fibers of the brushes


212


,


214


, the result is an absolute minimum possible motion quality impact.




The cleaning apparatus


210


is located via the two locating pins


220


, and holes or slots


220


in a back plate


224


on the inboard (IB) side, and two similar locating pins, and holes or slots on the outboard (OB) side. These locating holes or slots


220


, IB and OB, preferably are held within 0.35 mm, relative to machine datum. The locating pins


220


, and OB, which are preferably on the back plate


224


, similarly are held within 0.07 mm TP relative to the center of a donor roll within the cleaning apparatus moveable frame or housing


216


.




Each brush


212


,


214


will be held within 0.07 mm relative to a brush arm pivot (not shown), and a cam follower (not shown) for the brushes will be held within 0.07 mm, relative to the brush arm pivot. The donor roll which travels with the brushes will similarly be held within 0.07 mm relative to the-brush arm pivot, as well as will a camshaft for the cam follower by the brushes. Four cleaning assembly set screws (not shown) are provided and are adjustable to +/−0.127 mm, relative to the brushes


212


,


214


. The backer bars


202


,


204


themselves can be spring loaded against the cleaning assembly set screws.




As can be seen, there has been provided a motion-defect-free assembly and a method of minimizing cleaning apparatus induced motion quality disturbances in a moving belt photoreceptor of a toner image reproduction machine are provided. The assembly for practicing the method includes at least one resilient member located to each side of the moving belt photoreceptor at a desired belt cleaning station along a path of movement of the belt photoreceptor, and a cleaning apparatus that is mounted at the cleaning station and that includes at least one separately moveable cleaning member. The cleaning apparatus also includes a moveable frame having frame locating members, and the at least one separately moveable cleaning member. The motion-defect-free assembly also includes a drive and control system for first moving the moveable frame into contact with each of the locating members and for then separately moving, relative to the moveable frame, the at least one separately moveable cleaning member into contact and cleaning engagement with the moving belt photoreceptor, thereby minimizing cleaning apparatus induced motion quality disturbances in the moving belt photoreceptor.




While the invention has been described with reference to the structure herein disclosed, it is not confined to the details as set forth and is intended to cover any modification and changes that may come within the scope of the following claims.



Claims
  • 1. A method of minimizing cleaning apparatus induced motion quality disturbances in a moving belt photoreceptor of a toner image reproduction machine, the method comprising the steps of:a. providing at a desired belt cleaning station, a resilient member behind and to each side of the moving belt photoreceptor; b. mounting at the cleaning. station, a cleaning apparatus including at least one separately moveable cleaning member, and a moveable frame having frame locating members and supporting the at least one separately moveable cleaning member; c. first moving the moveable frame towards the moving belt photoreceptor and the resilient member to each side; d. next contacting each of the locating members of the moveable frame to the resilient member; and e. then separately moving, relative to the moveable frame, the at least one separately moveable cleaning member into cleaning contact with the moving belt photoreceptor, thereby minimizing cleaning apparatus induced motion quality disturbances in the moving belt photoreceptor.
  • 2. The method of claim 1, where said providing step comprises positioning at least one spring loaded backer bar behind and to each side of the moving belt photoreceptor at a belt cleaning station along a path of movement of the moving belt photoreceptor.
  • 3. The method of claim 1, where said at least one moveable cleaning member comprises a cleaning brush supported by a moveable frame.
  • 4. The method of claim 1, wherein said providing steps comprises providing at least one spring loaded backer bar supporting a backside of the moving belt photoreceptor and extending to each side thereof.
  • 5. The method of claim 1, wherein said providing step comprises providing at least a pair of spring loaded backer bars supporting a backside of the moving belt photoreceptor, and each spring loaded backer bar extending to each side of the moving belt photoreceptor.
  • 6. The method of claim 5, wherein said at least one moveable cleaning member comprises a pair of separately moveable cleaning brushes.
  • 7. A cleaning assembly for minimizing cleaning apparatus induced motion quality disturbances in a moving belt photoreceptor of a toner image reproduction machine, the cleaning assembly comprising:a. a plurality of resilient members positioned behind and to each side of the moving belt photoreceptor at a desired belt cleaning station; and b. a cleaning apparatus mounted to a frame of the machine at the desired belt cleaning station, said cleaning apparatus including: (i) at least one separately moveable cleaning member, and (ii) a moveable cleaner frame supporting said cleaning member and having frame locating members for locating against said resilient members prior to said cleaning member contacting and cleaning a portion of a surface of said moving belt photoreceptor.
  • 8. The cleaner assembly of claim 7, wherein each said resilient member comprises a spring loaded backer bar supporting a backside of the moving belt photoreceptor, and extending to each side the moving belt photoreceptor.
  • 9. The cleaner assembly of claim 7, wherein said cleaning member comprises a fibrous cleaning brush.
  • 10. A multipass color electrostatographic reproduction machine for producing color toner images without cleaning apparatus motion related image defects, the color electrostatographic reproduction machine comprising:(a) a machine frame; (b) a moving belt photoreceptor mounted to said machine frame and having an image bearing surface; (c) means for forming toner images electrostatically on said image bearing surface; (d) means for transferring the toner images from said image bearing surface onto a receiving substrate; and (e) a cleaning assembly for minimizing cleaning apparatus induced motion quality disturbances in said moving belt photoreceptor, said cleaning assembly comprising: (i) a plurality of resilient members positioned to each side of said moving belt photoreceptor and at a desired belt cleaning station; and (ii) a cleaning apparatus mounted to said machine frame at the desired belt cleaning station, said cleaning apparatus including at least one separately moveable cleaning member, and a moveable cleaner frame supporting said cleaning member and having locating members for locating against said resilient members prior to said cleaning member contacting and cleaning a portion said image bearing surface of said moving belt photoreceptor.
US Referenced Citations (2)
Number Name Date Kind
5669055 Thayer et al. Sep 1997 A
5930575 Fornalik et al. Jul 1999 A