Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2015-012005 filed Jan. 26, 2015. 
     BACKGROUND 
     (i) Technical Field 
     The present invention relates to a cleaning device and an image forming apparatus. 
     (ii) Related Art 
     In the related art, image forming apparatuses that form images using toner, and cleaners that clean residual toner using a cleaning blade, are known. 
     SUMMARY 
     According to an aspect of the invention, there is provided a cleaning device including: 
     a removal member that forms piled bodies of residual objects at a contact location and removes residual objects from a surface of a target cleaning member by contacting with the surface in a linear manner and rubbing against the surface; and 
     a smoothing member that smooths out the piled bodies by moving along the contact location. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein: 
         FIG. 1  shows a schematic configuration of a printer of an image forming apparatus according to an exemplary embodiment; 
         FIG. 2  is a perspective view that schematically shows a cleaning blade periphery inside a photosensitive member cleaner; 
         FIG. 3  is a side view that schematically shows a cleaning blade periphery inside the photosensitive member cleaner; 
         FIG. 4  shows another example of a smoothing member; and 
         FIG. 5  is a graph that represents results in which the abrasion of the cleaning blade is compared in an example and comparative examples. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. 
       FIG. 1  shows a schematic configuration of a printer of an image forming apparatus according to the exemplary embodiment. 
     A printer  10  that is shown in  FIG. 1  is a monochrome printer, and an image signal created outside the printer  10 , which represents images, is input to the printer  10  via a signal cable or the like, which is not shown. A control unit  11 , which controls the movements of each constituent element inside the printer  10 , is provided in the printer  10 , and the image signal is input to the control unit  11 . Further, in the printer  10 , the formation of images based on the image signal is performed under the control of the control unit  11 . 
     A paper sheet tray  21  is provided in a lower section of the printer  10 , and sheets of paper P are accommodated in the paper sheet tray  21  in a piled up state. The paper sheet tray  21  is configured so as to be capable of being freely withdrawn in order to replenish the sheets of paper P. 
     The sheets of paper P inside the paper sheet tray  21  are delivered to a registration roller  24  by a pickup roller  22  and a handling roller  23 . A transport timing of the sheets of paper P that arrive at the registration roller  24  is adjusted and the sheets of paper P are further transported. 
     A cylindrical photosensitive member  12 , which rotates with an orientation shown by an arrow A, is provided in the printer  10  above the registration roller  24 . Further, a charging device  13 , an exposure device  14 , a developing device  15 , a transfer device  16 , and a photosensitive member cleaner  17  are arranged in the vicinity of the photosensitive member  12 . The photosensitive member  12  corresponds to an example of an image holding member that is referred to in the present invention, a component in which the exposure device  14  and the developing device  15  are combined corresponds to an example of a formation device that is referred to in the present invention, and the transfer device  16  corresponds to an example of a transfer device that is referred to in the present invention. 
     The charging device  13  charges the surface of the photosensitive member  12 , and the exposure device  14  forms an electrostatic latent image by exposing the surface of the photosensitive member  12  in accordance with the image signal that is delivered from the control unit  11 . A toner image is formed as a result of the electrostatic latent image being developed by the developing device  15 . In this instance, the charging device  13  may be a contact type charging device that is provided with a charging roller or the like, or may be a non-contact type charging device that is provided with an electrical discharge wire or the like. The exposure device  14  may be an exposure device in which laser light is set as a light source, or may be an exposure device in which an LED or the like is set as the light source. In addition, the developing device  15  may be a developing device that uses a so-called two component developing agent in which a toner and a carrier are mixed, or may be a developing device that uses a developing agent in which a toner is the main component. 
     In this instance, the above-mentioned registration roller  24  feeds out the sheets of paper P so that the sheets of paper P reach a position that faces the transfer device  16  matching a timing with which toner images on the photosensitive member  12  reach the position. Further, the toner images on the photosensitive member  12  are transferred onto the sheets of paper P that are fed out by the transfer device  16 . 
     Toner (residual toner) that remains on the photosensitive member  12  after the transfer of toner images is removed from the photosensitive member  12  by the photosensitive member cleaner  17 . A rubber cleaning blade  170  is provided in the photosensitive member cleaner  17 , and the cleaning blade  170  has a long plate shape that extends along a direction which the cylindrical photosensitive member  12  extends. Further, the cleaning blade  170  contacts with the photosensitive member  12  in a linear manner at a side thereof that extends along the photosensitive member  12 . For convenience, there are cases in which the side that contacts with the photosensitive member  12  will be referred to as the edge of the cleaning blade  170 . Since the photosensitive member  12  rotates in contrast to the cleaning blade  170  being fixed, the cleaning blade  170  rubs against the surface of the photosensitive member  12  at the edge, and scrapes away and removes residual objects (such as residual toner, an external additive that is mixed in the toner, and paper dust that is derived from the sheets of paper P) from the surface of the photosensitive member  12  as a result of this action. This kind of photosensitive member cleaner  17  corresponds to a cleaning device according to the exemplary embodiment, and the cleaning blade  170  corresponds to an example of a removal member that is referred to in the present invention. 
     The sheets of paper P that receive the transfer of toner images progress further in the direction of an arrow B, and the toner images are fixed onto the sheets of paper P as a result of receiving heating and pressurization due to a fixing unit  18 . As a result of this, images that are formed from fixed toner images are formed on the sheets of paper P. 
     The sheets of paper P that pass through the fixing unit  18  progress in a direction of an arrow C toward a discharge unit  19 , are further delivered in a direction of an arrow D by the discharge unit  19 , and are discharged to a paper discharge holder  20 . 
     Given that, when residual objects are scraped away from the photosensitive member  12  surface by the cleaning blade  170 , a portion of the scraped away residual objects remains along the edge of the cleaning blade  170 , and piled bodies called toner dams and external additive dams are formed. Residual objects are reliably scraped away as a result of the presence of the piled bodies, and the maintenance of the piled bodies is required in the maintenance of the cleaning ability of the cleaning blade  170 . 
     However, for example, there is a concern that, a localized load will be applied to the cleaning blade  170  at locations with few piled bodies, and that the cleaning blade  170  will become damaged due to friction with the photosensitive member  12 , and therefore, that the cleaning ability thereof will be reduced when deviations occur in residual objects on the photosensitive member  12 , and piled bodies are unevenly distributed along the edge in cases in which one kind of image is formed continuously, or the like. Further, there are cases in which striped image defects occur when the cleaning ability falls in this manner. 
     In such an instance, a procedure for alleviating uneven distribution of the piled bodies is carried out on the photosensitive member cleaner  17  of the printer  10  that is shown in  FIG. 1 . 
       FIGS. 2 and 3  schematically show a cleaning blade periphery inside a photosensitive member cleaner,  FIG. 2  is a perspective view, and  FIG. 3  is a side view. 
     Multiple moving rods  171 , which extend so as to protrude toward the edge of the cleaning blade  170  are arranged inside the photosensitive member cleaner  17  along the edge. The moving rods  171  protrude from a downstream side toward an upstream of surface movement of the photosensitive member  12 . 
     As shown above, the edge of the cleaning blade  170  scrapes away residual objects from the photosensitive member  12  surface, and as a result, piled bodies  175  are formed along the edge of the cleaning blade  170 . Further, the tip end of each moving rod  171  protrudes to a position that reaches the piled bodies  175  but does not contact with the cleaning blade  170 . The moving rods  171  correspond to an example of a smoothing member that is referred to in the present invention. 
     The multiple moving rods  171  are supported by a support member  172  in a state of protruding from the support member  172 . Further, the support member  172  is held so as to be freely moveable in a direction that runs along the edge, and a gear  172   a  is formed on a side surface of the support member  172 . In addition, a so-called rack and pinion structure is formed by a pinion gear  173  engaging with the gear  172   a  of the support member  172 , and the pinion gear  173  rotates due to a motor  174 , which is controlled by the control unit  11  that is shown in  FIG. 1 . Each moving rod  171  moves along the edge of the cleaning blade  170  as a result of the pinion gear  173  rotating, and as a result, the piled bodies  175  are smoothed by the tip end of each moving rod  171 . Deviations in the piled bodies  175  are suppressed as a result of the piled bodies  175  being smoothed out, and a localized load on the cleaning blade  170  is reduced. Consequently, the cleaning ability of the cleaning blade  170  is maintained. 
     For example, the movement of the moving rods  171  is executed during pauses in image formation or the like. In addition, since multiple moving rods  171  are arranged along the edge, the piled bodies  175  are smoothed out across the entire length of the edge of the cleaning blade  170  as a result of each moving rod  171  moving a distance of an extent of a mutual interval, and the smoothing is completed in a short time. 
     Next, another example of a smoothing member that is referred to in the present invention will be described. 
       FIG. 4  shows another example of a smoothing member. 
     In this instance, an example in which a moving brush  176  is provided as a smoothing member, is shown. A tip end of the moving brush  176  is branched into multiple parts, and the piled bodies  175  are effectively smoothed out by the moving brush  176  that has this kind of branched tip end. 
     Next, the contribution of the smoothing member will be described based on an example. 
       FIG. 5  is a graph that represents results in which the abrasion of the cleaning blade is compared in an example and comparative examples. 
     In  FIG. 5 , respective abrasion amounts of the cleaning blade in a comparative example 1, in which toner with an average particle diameter of 7.0 μm is used and the smoothing member is not arranged, a comparative example 2, in which toner with an average particle diameter of 4.0 μm is used and the smoothing member is not arranged, and an example 1, in which toner with an average particle diameter of 4.0 μm is used and the same smoothing member as the example that is shown in  FIGS. 2 and 3  is arranged, are shown in a bar graph that represents a relative ratio in which the case of the comparative example 1 is set as 1.0. In the comparative example 2, the abrasion amount of the cleaning blade is increased by approximately five times in comparison with the comparative example 1. This increase in the abrasion amount is remarkable in small diameter toner in which the average particle diameter is 4.5 μm or less. Conversely, in cases in which the average particle diameter of the toner is larger than 7.0 μm, there is not a much difference from the abrasion amount of the example 1. 
     By the graph shown in  FIG. 5 , the fact that the abrasion amount in the example 1 is suppressed to an abrasion amount that does not differ much from the comparative example 1, is confirmed. In other words, in small diameter toner with an average particle diameter of 4.5 μm or less in which increases in the abrasion amount of the cleaning blade occur, the fact that the suppression of the abrasion amount as a result of providing the smoothing member is remarkable, is confirmed. Specifically, the increase in the abrasion amount is remarkable in a case of a volume average particle diameter of 4.8 μm or less. 
     Additionally, in the description of the above-mentioned exemplary embodiment, an example in which the smoothing member that is referred to in the present invention is moved using a rack and pinion method is shown, but the smoothing member that is referred to in the present invention may be moved using a belt driving method. 
     In addition, in the above-mentioned exemplary embodiment, a monochrome printer is shown byway of example, but the present invention may also be applied to a color device, and may also be applied to a facsimile, a copy machine, or a multifunction machine. 
     In addition, in the above-mentioned exemplary embodiment, a device that forms toner images using an electrophotography method is shown by way of example, but the formation device that is referred to in the present invention may be a device that directly draws toner images onto an image holding member using an electrode array or the like. 
     In addition, in the above-mentioned exemplary embodiment, a transfer device that directly transfers toner images from a photosensitive member to the sheets of paper is shown by way of example, but the transfer device that is referred to in the present invention may also be a device that indirectly transfers from an image holding member to a recording medium via an intermediate transfer member or the like. 
     In addition, in the above-mentioned exemplary embodiment, the sheets of paper are shown as a recording medium by way of example, but the recording medium that is referred to in the present invention may be OHP sheets, or may be plastic paper or the like. 
     The foregoing description of the exemplary embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.

Technology Category: g