Abstract:
An apparatus for cleaning an imaging surface with a cleaning blade including a drop seal actuator that urges a seal into position and then collects toner in the cleaner unit. The contamination seal captures falling accumulated toner from the blade which may contaminate the xerographic area when the cleaning blade is retracted from the imaging surface. Implementation of the actuator in contact with the drop seal positions the seal to contain toner within the cleaner.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates generally to a cleaner apparatus, and more particularly to an improved cleaning blade and drop seal actuator and seal in a cleaning system.  
         BACKGROUND OF THE INVENTION  
         [0002]    In the process of cleaning a photoreceptor or photoconductor, a cleaning blade is used to clean the imaging surface and toner is removed from the imaging surface which accumulates at the cleaning edge of the blade. As a result, toner contamination of the xerographic area occurs when the cleaning edge of the blade is retracted from the imaging surface. The toner that has accumulated at the blade edge falls down the imaging surface length during retraction. The toner contamination may result in copy quality defects and decreased operating efficiency of various xerographic components. In order to achieve engineering reliability, service and customer satisfaction goals improvements in cleaning blades and seals are desired to reduce such toner contamination problems.  
           [0003]    The following disclosures may be relevant to various aspects of the present invention and may be briefly summarized as follows:  
           [0004]    U.S. Pat. No. 5,966,565 relates to a cleaning seal with a soft cleaning seal tip that provides a seal between the cleaning housing and the photoconductive member in an electrophotographic machine. The cleaning seal is made of a relatively stiff material so that the cleaning seal can collect and support the toner removed from the photoconductive member. In the absence of the soft cleaning seal tip, the relatively stiff material of the cleaning seal contacting the photoconductive member excessively scratches the photoconductive member. The soft cleaning seal tip solves this problem by providing a relatively soft surface on the photoconductive member, resulting in fewer scratches on the photoconductive member. The composite cleaning seal provides the sufficient force to remove and support the toner removed from the photoconductive member while cushioning the force of the relatively stiff cleaning seal against the photoconductive member.  
           [0005]    U.S. Pat. No. 5,442,422 relates to an apparatus for cleaning an imaging surface with a hybrid cleaner that includes the implementation of a contamination seal in the cleaner unit. The contamination seal captures falling accumulated toner from the blade edge and in the brush nip, due to gravitation, which contaminates the xerographic area when the cleaner blade and disturber brush are retracted from the imaging surface. The contamination seal rests along the length of the blade portion that extends from the blade holder. In this position, the contamination seal does not touch the imaging surface to cause scratches nor does it interfere with the blade&#39;s ability to clean the imaging surface. Implementation of the contamination seal contains toner emission within the cleaner from the blade edge and brush nip.  
           [0006]    U.S. Pat. No. 4,910,560 relates to a cleaning device provided with a blade adapted to contact the peripheral surface of a photosensitive drum and wipe residual toner off of the photosensitive drum. A duct is disposed separately from the blade, and is adapted to remove the toner wiped off by the blade by air suction. In the interval between the blade and the duct, there is disposed a sealing member which serves to prevent ambient air from entering the duct through the interval. This sealing member is fixed either on a stationary region of a holder for the blade or on the basal end part of the blade integrated with the holder or on the outer surface of the duct, and contacts the duct if mounted on the holder or the blade, or contacts the blade or holder if mounted on the duct.  
           [0007]    U.S. Pat. No. 4,640,608 relates to a cleaning method which includes the cleaning blade being brought into pressure contact with the photoreceptor at least prior to the movement of the photoconductor, and moving the cleaning blade away from the surface of the photoconductor after the movement of the photoconductor is stopped with completion of the copying process. A stationary seal member allows uncleaned toner on the drum to pass therethrough but does not permit the toner removed by the cleaning blade to pass therethrough.  
           [0008]    U.S. Pat. No. 4,400,082 relates to a cleaning apparatus for removing toner remaining on a moving photoconductive member which has a resilient blade in bearing contact with surface of the photoconductive member and reciprocatingly movable laterally of the direction of movement of the surface, a seal member provided at each end of the photoconductive member and having a width in the direction of the lateral movement of the blade equal to at least the range of lateral movement of the corresponding end of the blade, the seal member being disposed in contact with the rear seal member being disposed in contact with the rear surface of the blade in the range of lateral movement of the blade end. Toner particles are thereby prevented from falling from the blade off the end of the photoconductive member.  
           [0009]    All documents cited herein, including the foregoing, are incorporated herein by reference in their entireties.  
         SUMMARY OF INVENTION  
         [0010]    In embodiments, there is provided an electrostatographic apparatus including a first member having a length, a first end, and a second end. The first end is for removing particles from a photoreceptor surface. The first end is adapted to move from an operative position contacting the photoreceptor surface to an inoperative position spaced from the photoreceptor surface. The second end is adapted to pivot and includes a second member associated therewith. A third member is spaced from the first member and has a length and a free end. The second member is adapted to contact the third member as the first member is moved to an inoperative position causing the third member to move an angular distance.  
           [0011]    In other embodiments, there is provided a customer replaceable unit including a cleaning blade assembly having a first end and a second end. The first end is for removing particles from a photoreceptor surface. The first end is adapted to move from an operative position contacting the photoreceptor surface to an inoperative position spaced from the photoreceptor surface. The second end has a protrusion thereon. A seal including a length and a free end is adapted to move from a first position to a second position as the first end of the cleaning blade assembly moves away from the photoreceptor surface and the protrusion contacts the seal at a position located a distance from the free end.  
           [0012]    In further embodiments, there is provided an apparatus for cleaning particles from a surface including a cleaning blade for removing particles from the surface. The cleaning blade is adapted to move between an operative position contacting the surface to remove particles therefrom and an inoperative position spaced from the surface. The cleaning blade includes a free blade end movable between the operative position and the inoperative position, and a pivot end for rotating about a pivot. A seal is movable between a first position and a second position in response to a protrusion on a portion of the pivot end moving in contact with the seal to urge the seal in the direction of the surface. The seal comprises a flexible sheet chosen from the group of materials consisting of polyester thermoplastics, polycarbonate, polyurethane, polyethylene, and polypropylene.  
           [0013]    In yet other embodiments, there is provided a cleaning station for cleaning toner from an endless photoconductive member in an apparatus including a cleaning housing. A cleaning blade assembly is supported by the cleaning housing. The cleaning blade assembly includes a first end and a second end. The first end is for removing particles from a photoconductive member. The first end is adapted to move from an operative position contacting the photoreceptor surface to an inoperative position spaced from the photoreceptor surface. The second end includes a protrusion thereon. A seal includes a length and a free end and is sufficiently stiff so that the seal can support the toner removed from the photoconductive member. The seal is located after the cleaning blade has removed the toner from the photoconductive member. The seal is movable from a first position to a second position as the first end of the cleaning blade assembly moves away from the photoreceptor surface such that the protrusion contacts the seal at a position located a distance from the free end.  
           [0014]    In other embodiments, there is provided a method of preventing toner contamination including: accumulating toner from a photoconductive surface on a free end of a blade, the blade comprising a pivot end including a protrusion thereon; and rotating the free end of the blade away from a surface causing the protrusion on the pivot end to pivot and contact the seal urging the seal to move toward the surface.  
           [0015]    Still other aspects of the invention will become readily apparent to those skilled in the art from the following detailed description, wherein embodiments are shown and described, simply by way of illustration. As will be realized, the invention is capable of other and different embodiments and methods of construction, and its several details are capable of modification and interchangeability in various obvious respects, all without departing from the invention. Accordingly, the drawing and description are to be regarded as illustrative in nature, and not as restrictive. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    [0016]FIG. 1 is a schematic elevational view of an embodiment of electrophotographic printing machine utilizing an embodiment of the drop seal actuator;  
         [0017]    [0017]FIG. 2 shows accumulation of toner at a cleaning edge of a cleaning blade in an operative position and a seal in contact with the photoreceptor;  
         [0018]    [0018]FIG. 3 shows retraction of the cleaning edge of the cleaning blade away from a photoreceptor and the drop seal actuator in contact with a seal; and  
         [0019]    [0019]FIG. 4 shows the return of the cleaning blade to an operative position and into contact with the photoreceptor and accumulation of toner falling into the container. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0020]    While the principles and embodiments of the present invention will be described in connection with an electrostatographic reproduction apparatus, it should be understood that the present invention is not limited to that embodiment or to that application. Therefore, it should be understood that the principles of the present invention and embodiments extend to all alternatives, modifications, and equivalents thereof.  
         [0021]    For a general understanding of the features of the present invention, reference is made to the drawings. In the drawings, like reference numerals have been used throughout to identify identical elements. FIG. 1 schematically depicts an electrophotographic printing machine incorporating the features of the present invention therein. It will become evident from the following discussion that the component with a precision aperture of the present invention may be employed in a wide variety of devices and is not specifically limited in its application to the particular embodiment depicted herein.  
         [0022]    Referring to FIG. 1 of the drawings, schematically illustrated is an electrophotographic printing or copying machine including a document positioned in a document handler  27  on a raster input scanner (RIS) indicated generally by reference numeral  28 . The RIS contains document illumination lamps, optics, a mechanical scanning drive and a charge coupled device (CCD) array. The RIS captures the entire original document and converts it to a series of raster scan lines. This information is transmitted to an electronic subsystem (ESS) which controls a raster output scanner (ROS) described below.  
         [0023]    The electrophotographic printing machine generally employs a photoconductive belt  10 . The photoconductive belt  10  may be made from a photoconductive material coated on a ground layer, which, in turn, is coated on an anti-curl backing layer. Belt  10  moves in the direction of arrow  13  to advance successive portions sequentially through the various processing stations disposed about the path of movement thereof. Belt  10  is entrained about stripping roller  14 , tensioning roller  16  and drive roller  20 . As roller  20  rotates, it advances belt  10  in the direction of arrow  13 .  
         [0024]    Initially, a portion of the photoconductive surface passes through charging station A. At charging station A, a corona generating device indicated generally by the reference numeral  22  charges the photoconductive belt  10  to a relatively high, substantially uniform potential.  
         [0025]    At an exposure station, B, a controller or electronic subsystem (ESS), indicated generally by reference numeral  29 , receives the image signals representing the desired output image and processes these signals to convert them to a continuous tone or greyscale rendition of the image which is transmitted to a modulated output generator, for example the raster output scanner (ROS), indicated generally by reference numeral  30 . Preferably, ESS  29  is a self-contained, dedicated minicomputer. The image signals transmitted to ESS  29  may originate from a RIS as described above or from a computer, thereby enabling the electrophotographic printing machine to serve as a remotely located printer for one or more computers.  
         [0026]    Alternatively, the printer may serve as a dedicated printer for a high-speed computer. The signals from ESS  29 , corresponding to the continuous tone image desired to be reproduced by the printing machine, are transmitted to ROS  30 . ROS  30  includes a laser with rotating polygon mirror blocks. The ROS is will expose the photoconductive belt to record an electrostatic latent image thereon corresponding to the continuous tone image received from ESS  29 . As an alternative, ROS  30  may employ a linear array of light emitting diodes (LEDs) arranged to illuminate the charged portion of photoconductive belt  10  on a rasterby-raster basis.  
         [0027]    After the electrostatic latent image has been recorded on photoconductive surface  12 , belt  10  advances the latent image to a development station, C, where toner, in the form of liquid or dry particles, is electrostatically attracted to the latent image using commonly known techniques. The latent image attracts toner particles from the carrier granules forming a toner powder image thereon. As successive electrostatic latent images are developed, toner particles are depleted from the developer material. A toner particle dispenser, indicated generally by the reference numeral  44 , dispenses toner particles into developer housing  46  of developer unit  38 .  
         [0028]    After the electrostatic latent image is developed, the toner powder image present on belt  10  advances to transfer station D. A print sheet  48  is advanced to the transfer station, D, by a sheet feeding apparatus,  50 . Preferably, sheet feeding apparatus  50  includes a nudger roll  51  which feeds the uppermost sheet of stack  54  to nip  55  formed by feed roll  52  and retard roll  53 . Feed roll  52  rotates to advance the sheet from stack  54  into vertical transport  56 . Vertical transport  56  directs the advancing sheet  48  of support material into the registration transport  120  of the invention herein, described in detail below, past image transfer station D to receive an image from photoreceptor belt  10  in a timed sequence so that the toner powder image formed thereon contacts the advancing sheet  48  at transfer station D. Transfer station D includes a corona generating device  58  which sprays ions onto the back side of sheet  48 . This attracts the toner powder image from photoconductive surface  12  to sheet  48 . The sheet is then detacked from the photoreceptor by corona generating device  59  which sprays oppositely charged ions onto the back side of sheet  48  to assist in removing the sheet from the photoreceptor. After transfer, sheet  48  continues to move in the direction of arrow  60  by way of belt transport  62  which advances sheet  48  to fusing station F.  
         [0029]    Fusing station F includes a fuser assembly indicated generally by the reference numeral  70  which permanently affixes the transferred toner powder image to the copy sheet. Preferably, fuser assembly  70  includes a heated fuser roller  72  and a pressure roller  74  with the powder image on the copy sheet contacting fuser roller  72 . The pressure roller is cammed against the fuser roller to provide the necessary pressure to fix the toner powder image to the copy sheet. The fuser roll is internally heated by a quartz lamp (not shown). Release agent, stored in a reservoir (not shown), is pumped to a metering roll (not shown). A trim blade (not shown) trims off the excess release agent. The release agent transfers to a donor roll (not shown) and then to the fuser roll  72 .  
         [0030]    The sheet then passes through fuser  70  where the image is permanently fixed or fused to the sheet. After passing through fuser  70 , a gate  80  either allows the sheet to move directly via output  84  to a finisher or stacker, or deflects the sheet into the duplex path  100 , specifically, first into single sheet inverter  82  here. That is, if the sheet is either a simplex sheet, or a completed duplex sheet having both side one and side two images formed thereon, the sheet will be conveyed via gate  80  directly to output  84 . However, if the sheet is being duplexed and is then only printed with a side one image, the gate  80  will be positioned to deflect that sheet into the inverter  82  and into the duplex loop path  100 , where that sheet will be inverted and then fed to acceleration nip  102  and belt transports  110 , for recirculation back through transfer station D and fuser  70  for receiving and permanently fixing the side two image to the backside of that duplex sheet, before it exits via exit path  84 .  
         [0031]    After the print sheet is separated from photoconductive surface  12  of belt  10 , the residual toner/developer and paper fiber particles adhering to photoconductive surface  12  are removed therefrom at cleaning station E. Cleaning station E includes a rotatably mounted fibrous brush in contact with photoconductive surface  12  to disturb and remove paper fibers and a cleaning blade to remove the non-transferred toner particles. The blade may be configured in either a wiper or doctor position depending on the application. Subsequent to cleaning, a discharge lamp (not shown) floods photoconductive surface  12  with light to dissipate any residual electrostatic charge remaining thereon prior to the charging thereof for the next successive imaging cycle.  
         [0032]    The various machine functions are regulated by controller  29 . The controller is preferably a programmable microprocessor which controls all of the machine functions hereinbefore described. The controller provides 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 the operator. Conventional sheet path sensors or switches may be utilized to keep track of the position of the document and the copy sheets.  
         [0033]    Reference is now made to FIG. 2, which shows a partial elevational view of a cleaning station E. The cleaning station E includes a cleaning blade  200  that contact the photoreceptor  210 . This cleaning station E is partially enclosed in a housing  220 . A brush (not shown) may be located upstream from the cleaning blade  200  and upstream from the direction of motion shown by arrow  230 , of the photoreceptor belt  210 . The brush may be used to mechanically clean and loosen toner  240  from the imaging surface of the photoreceptor  210 . The cleaning blade  200  removes the toner and other debris particles loosened and/or left behind by the brush from the photoreceptor  210 . The cleaning blade  200  is attached to a blade holder  250 . As the brush and blade  200  clean the imaging surface  12 , toner  240  removed from the imaging surface  12  accumulates at the cleaning edge of the blade  200 . The cleaning blade  200  may be mounted to a blade holder  250 , which is mounted pivotally about a pivot point  270 .  
         [0034]    A seal  260  may be mounted in the cleaning station E below the cleaning blade  200 . The seal  260  is movable and flexible and may contact or be slightly spaced from the photoreceptor  210 . The seal  260  can be made from materials such as: polycarbonate, polyurethane, polyethylene, polypropylene, polyester thermoplastics (e.g. Mylar) or any other material with low resistance to set. The seal  260  is stiff enough to prevent toner from escaping past the seal, when the seal is in contact with the photoreceptor.  
         [0035]    Reference is now made to FIG. 3, which shows a partial elevational view of a cleaning station E. In operation, a technical service representative may pull out a drawer (not shown) from the machine after the machine has been shut off. When the drawer is open, a handle  290  or a similar mechanism for rotation is exposed that allows the technical service representative to rotate the blade  200  away from the photoreceptor  210 , cause the photoreceptor  210  to assume a relaxed state, and to urge the end of the seal  260  further in the X direction to approach or contact the relaxed photoreceptor  210  as the drop seal actuator  295  urges and applies pressure to the seal  260 . The seal  260  may move an angle θ which, depending on embodiment geometry, may range up to  25  degrees. The photoreceptor  210  illustrated is in a generally relaxed state and the free end of the seal  260  may extend further in the X direction past where the photoreceptor  210  where located when in an operational state as shown in FIGS. 2 and 4. Applying pressure to the seal  260  on the photoreceptor  210  improves the capture of residual toner  240  during cleaning blade  200  retraction. The movement of the cleaning blade  200  away from the photoreceptor  210  as shown by arrow  300  cause the drop seal actuator to move into contact with the seal  260 . The toner  240  falls down the length of the seal  260  and is gathered and held at the intersection of the seal  260  and the drop seal actuator  295 . The seal  260  directs accumulated toner  240  at the blade  200  away from the xerographic area and into the container  280 .  
         [0036]    The purpose of the drop actuator seal  295  is to reduce or eliminate a toner contamination problem in the xerographic area. The increased pressure to the seal  260  upon retraction of the blade  200  and use of the drop seal actuator  295  in the cleaning system helps to prevent the contamination of the xerographic area and components, allowing for a cleaner copier or printer and help to improve copy quality, operating efficiency, reliability and life of various xerographic components such as charge devices, erase lamps and sensors. If the seal  260  has an attack angle too great, includes material that is too stiff, or has an edge that is too rough, then undue photoreceptor abrasion can occur. Premature photoreceptor abrasion greatly lessens photoreceptor life thus lowering the CRU life. If the seal  260  does not extend far enough or it is installed unevenly, then toner can easily pass over it and land onto the scorotron below. Any scorotron contamination reduces print quality and lowers the CRU life.  
         [0037]    The drop seal actuator  295  simultaneously moves into position as the cleaning blade  200  moves out of its run position. Also, the photoreceptor  210  is relaxed as the cleaning blade moves out of its cleaning position. The seal  260  has a position A during operation. Upon retraction of the cleaning blade during the process of CRU removal, the drop seal actuator  295  contacts the seal, and urges the seal  260  out of position A in the direction toward the relaxed photoreceptor  210 , and moves the seal  260  an angle θ from position A to a position A′. The end of the seal  260  in its position A′ extends further in the X direction to a region where the photoreceptor  210  may have been position in its operational position. The end of the seal  260  is then positioned to catch loose toner falling from the blade  200  and photoreceptor  210 . Toner and other debris is then directed along the seal  260  and eventually into the waste container  280 . The angle θ depends on the geometry of the cleaning unit and positioning of the relaxed photoreceptor  210 . The seal  260  in position A′ may be arcuate or include a straight portion depending on the position of the photoreceptor  210 , how far the seal extends in the X direction, whether the end of the seal  260  contacts the photoreceptor  210 , and geometry. In embodiments, angle θ may range up to 25 degrees.  
         [0038]    In FIG. 4, shown is a partial elevational view of a cleaning station E. The blade  200  is shown in contact with the photoreceptor  210  and the actuator  295  is shown moved away from the seal  260 . The seal is in a free state without contact or pressure from the drop seal actuator  295 . Residual toner  240  previously directed or captured by the seal  200  and actuator  295  is gravitationally urged toward the waste container  280  as the cleaning blade  200  is returned to it&#39;s operative position and the drop seal actuator  295  simultaneously moved out of contact and spaced away from the seal  260 . The printer or copying machine is now ready for operation again.  
         [0039]    In embodiments, the movement of the seal over an angular distance θ may range up to 25 degrees when the first member such as a cleaning blade is in an inoperative position. The angular distance θ may be increased during the process of moving the first member to an inoperative position. The third member such as a seal may not be straight when the second member such as a protrusion contacts the third member and applies pressure thereto. The second member may be a protrusion on an end of a cleaning blade. The second member may have a length, width, and thickness and be selectively positioned on the cleaning blade. There may be no opening between the second member and the third member when the second member contacts the third member. The third member may be substantially straight when the first member is in an operative position and the second member is out of contact from the third member. The third member may not be substantially straight when the first member is in an inoperative position and the second member is in contact with third member. The first member may be made of metal, the second member may be made of a urethane and the third member may be made of mylar. The urethane may be a foam. The second member and the first member may be made of one piece and the same material. The cleaning blade may be removable away from the photoreceptor surface. The apparatus may further include a waste container adapted to receive particles. The third member may include a flexible sheet chosen from the group of materials consisting of polyester thermoplastics, polycarbonate, polyurethane, polyethylene, and polypropylene. The particles may be captured by the seal and directed therealong into said waste container. The cleaning seal may be between 2-5 mils thick and be made of at least one of Mylar, and polyester. The seal may have a thickness of about 3 mils.  
         [0040]    In embodiments, the method may further include: capturing between the seal and the protrusion loose toner falling from the blade; allowing the toner to be directed along a length of the seal into the waste container; returning the cleaning blade into contact with the imaging surface; moving the protrusion out of contact with the seal and causing the seal to straighten; locating the seal with respect to the cleaning blade so that toner removed and falling past the cleaning blade is supported by the cleaning seal.  
         [0041]    In summary, the drop seal actuator is a mechanical device that provides additional protection from toner droppings falling from the cleaner system onto the charging system. The drop seal actuator is useful in systems where, for example, a Xerographic CRU has a cleaner system that is directly above the charging system. In operation, while removing the CRU from the machine, the customer actuates the belt module handle which moves the cleaner blade away from the photoreceptor. When the blade moves from the photoreceptor, excess toner may spill from the cleaner blade. To prevent contamination from falling onto the charge scorotron, a seal is located between the cleaning system and the charging system. During normal run, the seal may lightly touch the photoreceptor. At CRU removal, photoreceptor is relaxed and the seal is urged and repositioned toward the relaxed photoreceptor by contact of the drop seal actuator with the seal. The seal then catches and directs loose toner away from the charging system and reduces contamination of the charging system.  
         [0042]    While this invention has been described in conjunction with various embodiments, it is evident that many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications, and variations and their equivalents.