Abstract:
A cleaning device includes a removal member that removes residual objects from a surface of a target cleaning body by contacting with the surface in a linear manner and rubbing against the surface and forms a piled body which is constructed of a portion of the residual objects at a contact location, and a pressure device that presses the piled body to increase a strength of the piled body.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2015-007403 filed Jan. 19, 2015. 
     BACKGROUND 
     Technical Field 
     The present invention relates to a cleaning device and an image forming apparatus. 
     SUMMARY 
     According to an aspect of the invention, there is provided a cleaning device including:
         a removal member that removes residual objects from a surface of a target cleaning body by contacting with the surface in a linear manner and rubbing against the surface and forms a piled body which is constructed of a portion of the residual objects at a contact location; and   a pressure device that presses the piled body to increase a strength of the piled body.       

    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein: 
         FIG. 1  is a schematic configuration drawing of a printer that is a first exemplary embodiment of an image forming apparatus of the present invention; 
         FIG. 2  is a drawing that schematically shows a cleaning blade periphery inside a photosensitive body cleaner; 
         FIG. 3  is a drawing that shows an aspect during reversal in a reinforcement action of a piled body; 
         FIG. 4  is a drawing that shows an aspect during pressure in the reinforcement action of the piled body; 
         FIG. 5  is a drawing that shows an aspect during normal rotation return in the reinforcement action of the piled body; 
         FIG. 6  is a drawing that schematically shows a cleaning blade periphery inside a photosensitive body cleaner in a second exemplary embodiment; 
         FIG. 7  is a drawing that shows an aspect during reversal in a reinforcement action of a piled body in the second exemplary embodiment; 
         FIG. 8  is a drawing that shows an aspect during a second reversal in the reinforcement action of the piled body in the second exemplary embodiment; 
         FIG. 9  is a drawing that shows an aspect during pressure in the reinforcement action or the piled body in the second exemplary embodiment; 
         FIG. 10  is a drawing that shows an aspect during normal rotation return in the reinforcement action of the piled body in the second exemplary embodiment; 
         FIG. 11  is a drawing that schematically shows a cleaning blade periphery inside a photosensitive body cleaner in a third exemplary embodiment; 
         FIG. 12  is a drawing that shows an aspect during normal image formation in the third exemplary embodiment; 
         FIG. 13  is a drawing that shows an aspect during pressure in a reinforcement action of a piled body in the third exemplary embodiment; and 
         FIG. 14  is a drawing that shows an aspect during posture return in the reinforcement action of the piled body in the third exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. 
     First Exemplary Embodiment 
       FIG. 1  is a schematic configuration drawing of a printer that is the first exemplary embodiment of an image forming apparatus of the present invention. 
     A printer  10  that is shown in  FIG. 1  is a monochrome printer, and an image signal created outside the printer  10 , which represented by images, is input to the printer  10  via a signal cable, 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 are 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 stored 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 separating roller  23 . A transport timing of 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 body  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 unit  13 , an exposure unit  14 , a developing unit  15 , a transfer unit  16 , and a photosensitive body cleaner  17  are arranged in the vicinity of the photosensitive body  12 . The photosensitive body  12  corresponds to an example of an image holding body that is referred to in the present invention, a component in which the exposure unit  14  and the developing unit  15  are combined corresponds to an example of formation equipment that is referred to in the present invention, and the transfer unit  16  corresponds to an example of a transfer device that is referred to in the present invention. 
     The charging unit  13  charges the surface of the photosensitive body  12 , and the exposure unit  14  forms an electrostatic latent image by exposing the surface of the photosensitive body  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 unit  15 . In this instance, the exposure unit  14  may be an exposure device in which laser light is set as a light source, or may be an exposure device in which LEDs or the like are set as the light source. In addition, the developing unit  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. A so-called external additive is mixed into the toner in the developing agent, the particle size of the external additive is smaller than that of toner particles, and the external additive is adhered to the surface of the toner particles. Furthermore, it is desirable that the external additive is processed with oil content such as silicone oil. 
     In this instance, the above-mentioned registration roller  24  feeds out sheets of paper P so as to reach a position that faces the transfer unit  16  matching a timing with which toner images on the photosensitive body  12  reach the position. Further, the toner images on the photosensitive body  12  receive the action of the transfer unit  16 , and are transferred onto the sheets of paper P that are fed out. 
     Toner (residual toner) that remains on the photosensitive body  12  after the transfer of toner images is removed from the photosensitive body  12  by the photosensitive body cleaner  17 . A rubber cleaning blade  170  is provided in the photosensitive body cleaner  17 , and the cleaning blade  170  has a long plate shape that extends along a direction which the cylindrical photosensitive body  12  extends. Further, the cleaning blade  170  contacts with the photosensitive body  12  in a linear manner at a side thereof that extends along the photosensitive body  12 . For convenience, there are cases in which the side that contacts with the photosensitive body  12  will be referred to as the edge of the cleaning blade  170 . Since the photosensitive body  12  rotates in contrast to the cleaning blade  170  being fixed, the cleaning blade  170  rubs against the surface of the photosensitive body  12  at the edge, and scrapes away and removes residual objects (such as residual toner, the external additive that is mixed in with the toner, and paper dust that is derived from the sheets of paper P) from the surface of the photosensitive body  12  as a result of this action. This kind of cleaning blade  170  corresponds to an example of a removal member that is referred to in the present invention. 
     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 pressure due to a fixing unit  18 . As a result of this, images that are formed from 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 platform  20 . 
     Given that, when residual objects are scraped away from the photosensitive body  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 important to the maintenance of the cleaning ability by the cleaning blade  170 . In particular, since the particle diameter of the external additives is small, damage to the cleaning blade  170  due to abrasion is prevented by gaps between the edge and the photosensitive body  12  surface, gaps between particles of toner, and the like being filled in, and therefore, the cleaning ability of the cleaning blade  170  is improved. 
     However, for example, there is a concern that, the cleaning blade  170  will become damaged doe to friction with the photosensitive body  12 , and therefore, the cleaning ability thereof will be reduced when the residual objects on the photosensitive body  12  are decreased and the piled bodies are reduced as a result in cases in which low concentration images are formed continuously, or the like. Further, there are cases in which striped image defects occur when the cleaning ability falls in this manner. In a case in which the toner is a toner with a small diameter of less than or equal to 4.5 μm, damage to the cleaning blade  170  is remarkable in accordance with the continuance of low concentration images. 
     In such an instance, a device for maintaining the piled bodies is applied to the photosensitive body cleaner  17  of the printer  10  that is shown in  FIG. 1 . 
       FIG. 2  is a drawing that schematically shows a cleaning blade periphery inside a photosensitive body cleaner. 
     In the present exemplary embodiment, a pressure unit  171 , is provided on an upstream side (that is, a transfer unit  16  side) of a location at which the cleaning blade  170  and the surface of the photosensitive body  12  contact, with one another. The pressure unit  171  includes a solenoid  172  and a pressure member  173 , and the pressure member  173  is attached to a tip of a core of the solenoid  172 . In addition, the pressure unit  171  also includes a drawn spring  174  that draws the pressure member  173  and a main body of the solenoid  172  toward one another. The actions of the pressure unit  171  are controlled by the control unit  11  that is shown in  FIG. 1 , the pressure member  173  is drawn up to the top of  FIG. 2  by the drawn spring  174  when the solenoid  172  is off, and the pressure member  173  is pushed by the solenoid  172  and moves toward the bottom of  FIG. 2  when the solenoid  172  is turned on. The pressure unit  171  corresponds to an example of a pressure device that is referred to in the present invention. 
     Actions of the present exemplary embodiment which is provided with this kind of pressure unit  171  will be described next. 
     During normal image formation, as shown in  FIG. 2 , the surface of the photosensitive body  12  moves to a right direction in the drawing, the surface of the photosensitive body  12  is scrubbed by the edge of the cleaning blade  170 , and residual objects are scraped away. As a result of this, piled bodies  175  of the residual objects are generated along the edge of the cleaning blade  170 . In the present exemplary embodiment, the piled bodies  175  are formed by toner dams  175   a  that, are mainly formed from toner, and external additive dams  175   b  that are mainly formed from external additive, and since the particle diameter of the external additive is small, the external additive dams  175   b  are formed in locations that are closer to the edge than the toner dams  175   a . Additionally, in  FIG. 2 , the toner dams  175   a  and the external additive dams  175   b  are shown conceptually, and the specific shapes and the like thereof are not shown accurately. 
     In a case in which image formation by the printer  10  satisfies a condition such as reaching a predetermined number of sheets for example, a reinforcement action of the piled bodies  175  is performed as a result of the control of the control unit  11  that is shown in  FIG. 1  during a pause of an interval in image formation. 
       FIGS. 3 to 5  are drawings that show a reinforcement action of piled bodies. 
     When the reinforcement action of the piled bodies is initiated, the control unit  11  gives an instruction for the reversal of the photosensitive body  12 . As shown in  FIG. 3 , the photosensitive body  12  is reversed to an extent that the piled bodies  175  move from the edge of the cleaning blade  170  to below (that is, a facing location between the pressure unit  171  and the photosensitive body  12 ) the pressure unit  171 . 
     After reversal in this manner, as shown in  FIG. 4 , pressure is performed by the pressure unit  171 . That is, the solenoid  172  pushes the pressure member  173  out as a result of a driving signal being delivered from the control unit  11  to the solenoid  172 , and the piled bodies  175  are pressed between the pressure member  173  and the photosensitive body  12 . For example, it is preferable that the pressure be 3.0 g/cm 2 , as a result of this pressure, the piled bodies  175  are pressed together and reinforced. In addition, as a result of the pressure, oil component seeps out from the external additive that is included in the piled bodies  175 , and the oil exhibits an effect of solidifying the piled bodies  175 , and an effect of improving the lubrication of the photosensitive body  12  surface. 
     The piled bodies  175  that are pressed in this manner are returned to the edge of the cleaning blade  170  as shown in  FIG. 5 . That is, the drawn spring  174  draws the pressure member  173  back as a result of the driving signal from the control unit  11  to the solenoid  172  being shut off, and the piled bodies  175  return to the edge of the cleaning blade  170  as a result of the photosensitive body  12  rotating in the right direction in the drawing under the control of the control unit  11 . In this manner, since the piled bodies  175  that have returned to the edge are pressed together and reinforced, even in a case in which low concentration images are formed continuously, it is difficult for the piled bodies  175  to be reduced, and therefore, cleaning ability by the cleaning blade  170  is stabilized. 
     Additionally, for example, the pressure device that is referred to in the present invention may be a pressure device which is provided on a side of the edge of the cleaning blade  170 , and which continuously applies pressure to the piled bodies  175 , but from a viewpoint of preventing a so-called filming phenomenon in which components of toner melt, and take on a filmy form and become adhered to the photosensitive body  12  surface, it is desirable that the pressure of the piled bodies  175  is temporary. 
     Second Exemplary Embodiment 
     The description of the first exemplary embodiment has been completed above, and next, the second exemplary embodiment will be described. Since, apart from the structure of the cleaning blade  170  periphery inside the photosensitive body cleaner  17  differing, the second exemplary embodiment is the same as the first exemplary embodiment, overlapping description will be omitted. 
       FIG. 6  is a drawing that schematically shows a cleaning blade periphery inside a photosensitive body cleaner in the second exemplary embodiment. 
     In the second exemplary embodiment, the pressure unit  171 , is provided on an upstream side (that is, a transfer unit  16  side) of a location at which the cleaning blade  170  and the surface of the photosensitive body  12  contact with one another. In addition, in the second exemplary embodiment, a nozzle of an air discharging unit  176  is provided between the cleaning blade  170  and the pressure unit  171 . The air discharging unit  176  includes a pipe and a pump (not illustrated) that deliver air to the nozzle shown in  FIG. 6 , and the discharging of air from the nozzle is turned on and off in accordance with the control of the control unit  11  that is shown in  FIG. 1 . 
     Actions of the second exemplary embodiment will be described. 
     During normal image formation, as shown in  FIG. 6 , the surface of the photosensitive body  12  moves to the right direction in the drawing, the surface of the photosensitive body  12  is scrubbed by the edge of the cleaning blade  170 , and residual objects are scraped away. As a result of this, the piled bodies  175  are generated along the edge of the cleaning blade  170 . In the second exemplary embodiment, the piled bodies  175  are also formed by the toner dams  175   a , and the external additive dams  175   b . In addition, in the second exemplary embodiment, a reinforcement action of the piled bodies  175  is also performed as a result of the control of the control unit  11  that is shown in  FIG. 1  during a pause of an interval in image formation. 
       FIGS. 7 to 10  are drawings that show a reinforcement action of piled bodies in the second exemplary embodiment. 
     When the reinforcement action of the piled bodies is initiated, the control unit  1  gives an instruction for the reversal of the photosensitive body  12 . As shown in  FIG. 7 , in the second exemplary embodiment, the photosensitive body  12  is reversed to an extent that the piled bodies  175  move from the edge of the cleaning blade  170  to below (that is, a facing location between the nozzle and the photosensitive body  12 ) the nozzle of the air discharging unit  176 . 
     After reversal in this manner, the discharging of air by the air discharging unit  176  is performed, and components of the toner dams  175   a  are blown away from the piled bodies  175 . As a result of this, as shown in  FIG. 8 , piled bodies in which the components of the external additive dams  175   b  are largely predominant remain. The air discharging unit  176  corresponds to an example of a reduction unit that is referred to in the present invention. In this manner, it is desirable that a ratio of the external additive with respect to toner in the remaining piled bodies is greater than or equal to 100% in weight ratio. Further, the control unit  11  gives an instruction for a second reversal of the photosensitive body  12 , and the external additive dams  175   b , which is the piled bodies  175 , is moved to below (that is, a facing location between the pressure unit  171  and the photosensitive body  12 ) the pressure unit  171 . 
     Next, as shown in  FIG. 9 , pressure is performed by the pressure unit  171 . That is, the solenoid  172  pushes the pressure member  173  out as a result of a driving signal being delivered from the control unit  11  to the solenoid  172 , and the external additive dams  175   b  (the piled bodies) are pressed between the pressure member  173  and the photosensitive body  12 . As a result of the pressure, the external additive dams  175   b  (the piled bodies) are pressed together and reinforced. At this time, oil component seeps out from the external additive, and exhibits the same effect of solidifying the piled bodies, and the effect of improving the lubrication of the photosensitive body  12  surface in the same manner as the first exemplary embodiment, but since the ratio of the predominant external additive in the piled bodies is high, the piled bodies are solidified more tightly than the first exemplary embodiment. 
     The external additive dams  175   b  (piled bodies) that are pressed in this manner are returned to the edge of the cleaning blade  170  as shown in  FIG. 10 . That is, the drawn spring  174  draws the pressure member  173  back as a result of the driving signal from the control unit  11  to the solenoid  172  being shut off, and the external additive dams  175   b  (piled bodies) return to the edge of the cleaning blade  170  as a result of the photosensitive body  12  rotating in the right direction in the drawing under the control of the control unit  11 . In this manner, since the external additive dams  175   b  (the piled bodies) that have returned to the edge are reinforced more than in the first exemplary embodiment, cleaning ability by the cleaning blade  170  is further stabilized. 
     Third Exemplary Embodiment 
     The description of the second exemplary embodiment has been completed above, and next, the third exemplary embodiment will be described. Since, apart from the structure of the cleaning blade  170  periphery inside the photosensitive body cleaner  17  differing, the third exemplary embodiment is the same as the first exemplary embodiment, overlapping description will be omitted. 
       FIG. 11  is a drawing that schematically shows a cleaning blade periphery inside a photosensitive body cleaner in the third exemplary embodiment. 
     In the third exemplary embodiment, the cleaning blade  170  and a metal holding plate  177 , which holds the cleaning blade  170  freely rotate in an integral manner through an angular range of an extent in which a location (the edge) at which the cleaning blade  170  and the photosensitive body  12  surface contact with one another is set as a center. Further, a rotation cam  178  for rotating the metal holding plate  177  on the cleaning blade  170 , and a drawn spring  179  are provided. By the drawn spring  179 , the metal holding plate  177  is drawn so as to always contact with the rotation cam  178 , and the posture of cleaning blade  170  and the metal holding plate  177  changes from a first state that is shown by a solid line in the drawing to a second state that is shown by a dotted line in the drawing as a result of the rotation cam  173  rotating. The rotation cam  178  is rotated by a motor, which is not illustrated, and the driving of the motor and the rotation cam  178  is controlled by the control unit  11  that is shown in  FIG. 1 . 
     Actions of the third exemplary embodiment will be described. 
       FIG. 12  is a drawing that shows an aspect during normal image formation in the third exemplary embodiment. 
     During normal image formation, the cleaning blade  170  is in the first state that is mentioned above, and the surface of the photosensitive body  12  moves to the right direction in the drawing, the surface of the photosensitive body  12  is scrubbed by the edge of the cleaning blade  170 , and residual objects are scraped away. As a result of this, the piled bodies  175  of the residual objects are generated along the edge of the cleaning blade  170 . In addition, in the third exemplary embodiment, a reinforcement action of the piled bodies  175  is also performed as a result of the control of the control unit  11  that is shown in  FIG. 1  during a pause of an interval in image formation. 
       FIGS. 13 and 14  are drawings that show a reinforcement action of piled bodies in the third exemplary embodiment. 
     When the reinforcement action of the piled bodies is initiated, the control unit  11  gives an instruction for the stop of the photosensitive body  12 , and the control unit  11  drives the rotation cam  178  that is shown in  FIG. 11 , and as shown in  FIG. 13 , the cleaning blade  170  rises to the second state that is mentioned above. In this manner, as a result of the change in the posture of the cleaning blade  170 , the piled bodies  175  are interposed between the tip end of the cleaning blade  170  and the photosensitive body  12  surface, and the piled bodies  175  are pressed. In other words, in the third exemplary embodiment, the cleaning blade  170  also functions as the pressure device that is referred to in the present invention. 
     Even in pressure with this kind of technique, the piled bodies  175  are pressed together and reinforced. In addition, in the third exemplary embodiment, oil component also seeps out from the external additive that is included in the piled bodies  175  by pressure, and the oil exhibits the effect of solidifying the piled bodies  175 , and the effect of improving the lubrication of the photosensitive body  12  surface. 
     When the piled bodies  175  are reinforced by pressure, the rotation cam  178  that is shown in  FIG. 11  is driven by the control unit  11 , and as shown in  FIG. 14 , the cleaning blade  170  returns to the first state that is mentioned above. Further, rotation of the photosensitive body  12  is restarted, and the reinforced piled bodies  175  are pushed against the edge of the cleaning blade  170 . In the same manner as the first exemplary embodiment, even in a case in which low concentration images are formed continuously, it is difficult for the piled bodies  175  that are reinforced in this manner to be reduced, and therefore, cleaning ability by the cleaning blade  170  is stabilized. 
     Additionally, in the above-mentioned exemplary embodiments, an example in which toner components in the piled bodies are reduced by the discharging of air is shown as a reduction unit that is referred to in the present invention, but, for example, the reduction unit may be a device that reduces a toner component using an electrostatic effect or the like. 
     In addition, in the above-mentioned exemplary embodiments, a monochrome printer is illustrated by way 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 embodiments, a device that forms toner images using an electrophotography method is illustrated 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 body by an electrode array or the like. 
     In addition, in the above-mentioned exemplary embodiments, a transfer device that directly transfers toner images from a photosensitive body to sheets of paper is illustrated 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 body to a recording medium via an intermediate transfer body or the like. 
     In addition, in the above-mentioned exemplary embodiments, sheets of paper are illustrated 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.