Patent Publication Number: US-11397399-B2

Title: Cleaning member with ends of blade thereof bent toward image carrier

Description:
BACKGROUND 
     An image forming apparatus may be an apparatus that develops a black and white image or a color image on paper according to an image signal. Examples of an image forming apparatus, include laser printers, inkjet printers, copying machines, multi-function printers, facsimiles, etc. 
     In an electrophotographic image forming apparatus, a visible toner image is generated from an electrostatic latent image by attaching toner to a photosensitive drum or an intermediate transfer belt on which the electrostatic latent image is formed, and transferring the toner image onto paper. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram illustrating an example configuration of an example image forming apparatus; 
         FIG. 2  is a front view of an example cleaning member and an example intermediate transfer belt; 
         FIG. 3  is a perspective view of an example cleaning member; 
         FIG. 4  is an enlarged view of a portion indicated by IV in  FIG. 2 ; 
         FIG. 5  is a schematic diagram illustrating a cleaning angle between a cleaning member and an image carrier according to an example of the disclosure; 
         FIG. 6  is a cross-sectional view of the cleaning member and a portion of the intermediate transfer belt illustrated in  FIG. 4 , taken along the lines I-I and II-II; and 
         FIG. 7  is a graph illustrating line pressure and cleaning angles according to each point of an example cleaning member. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, with reference to the drawings, the same reference numbers are assigned to the same components or to similar components having the same function, and overlapping description is omitted. 
     In the present disclosure, the expression “connected to”, for example when one element is described as being “connected to” another element, may refer to both a case where the one element is ‘directly connected to’ the other element, and a case where one element is ‘connected to another element through another element’ (e.g., connected indirectly). In addition, the expression “includes”, for example when one element “includes” another element, may refer to a state where other elements may additionally be included, without excluding other elements unless there is any specific description to the contrary. 
     In the present disclosure, the term “image forming job” may refer to various jobs (e.g., printing, scanning or faxing) related to images and imaging, such as formation of images or generation/storing/transmission of image files, etc., for example. In addition, the term “job” may refer to an image forming job, and may also include all of a series of processes and operations for performing an image forming job. 
     In addition, the term “image forming apparatus” may refer to an apparatus or device that prints printing data generated at a terminal apparatus such as a computer for example, onto paper or recording paper. As examples of such an image forming apparatus, there are copying machines, printers, facsimiles or multi-function printers (MFPs) that implement multiple functions of the aforementioned apparatuses through one apparatus, etc. In addition, an image forming apparatus may refer to any apparatus capable of performing image forming jobs such as printers, fax machines, multi-function printers (MFPs) or display apparatuses, etc. 
     In addition, the term “user” may refer to a person who performs operations related to an image forming job by using an image forming apparatus, or a device connected to an image forming apparatus through wire or wirelessly. 
       FIG. 1  is a diagram illustrating a schematic configuration of an example image forming apparatus  1 . 
     As illustrated in  FIG. 1 , the example image forming apparatus  1  may include a main body  10 , a paper supply apparatus  20 , an exposure apparatus  30 , a photosensitive drum, a developing device, a transferring apparatus  60 , a fuser  70 , and a paper eject apparatus  80 . 
     The main body  10  may form the exterior of the image forming apparatus  1 , and may house and/or support various components installed inside the image forming apparatus  1 . 
     The paper supply apparatus  20  supplies paper S (e.g., sheets of paper S) toward the transferring apparatus  60 . The paper supply apparatus  20  may include a cassette  21  storing the paper S, a pick-up roller  22  that picks up the paper S stored in the cassette  21  one at a time, and a feed roller  23  that feeds the picked-up paper S toward the transferring apparatus  60 . 
     The exposure apparatus  30  may be arranged in a lower part of the developing device, and may project light corresponding to image information on the photosensitive drum, and thereby form an electrostatic latent image on the surface of the photosensitive drum. 
     The photosensitive drum includes a metal drum having a cylindrical shape, and a light conductive layer formed on the outer circumference of the metal drum. The photosensitive drum is an image carrier that carries an electrostatic latent image formed by the exposure apparatus  30  and a toner image formed by the developing device. The photosensitive drum may be rotatably installed inside the main body  10 . 
     A charge roller  41  is installed within (inside) the main body  10 . The charge roller  41  charges the photosensitive drum to a predetermined potential before the exposure apparatus  30  projects light onto the photosensitive drum. The charge roller  41  may be a charge device that charges the photosensitive drum to a uniform potential. The charge roller  41  may provide electric charges while rotating in a contact or non-contact state with the outer circumferential surface of the photosensitive drum, and thereby charge the outer circumferential surface of the photosensitive drum to a uniform potential. 
     The developing device forms a toner image by supplying a toner (e.g., a developing agent) to the photosensitive drum on which an electrostatic latent image was formed. The developing device may include four developing devices  50 K,  50 C,  50 M,  50 Y wherein toners in different colors, for example, toners in black (K), cyan (C), magenta (M), and yellow (Y) colors are respectively accommodated. 
     In each of the developing devices  50 K,  50 C,  50 M,  50 Y, a toner to be supplied to each photosensitive drum  40 K,  40 C,  40 M,  40 Y is stored, and a toner image may be formed by attaching the stored toners to the surface of the photosensitive drum on which an electrostatic latent image was formed. 
     The transferring apparatus  60  may include an intermediate transfer belt  61  and an intermediate transfer roller. 
     The intermediate transfer belt  61  also may be an image carrier that carries a toner image formed by the developing device. 
     The intermediate transfer belt  61  may be supported by a driving roller  65  and a driven roller  67  and may run at the same speed as the line speed of the photosensitive drum. The length of the intermediate transfer belt  61  may be formed to be the same as or at least longer than the length of the paper S (sheet of paper) used for the image forming apparatus  1 . 
     In each of the developing devices  50 K,  50 C,  50 M,  50 Y, the intermediate transfer roller faces the photosensitive drum with the intermediate transfer belt  61  in between, and transfers a toner image formed on the facing photosensitive drum onto the intermediate transfer belt  61 . There may be a plurality of intermediate transfer rollers  62 K,  62 C,  62 M,  62 Y to correspond to the plurality of photosensitive drums  40 K,  40 C,  40 M,  40 Y. A first transfer bias voltage for transferring a toner image formed on the photosensitive drum to the intermediate transfer belt  61  is applied to the intermediate transfer roller. The first transfer bias voltage is a voltage having a polarity that is opposite (an opposite polarity) to the polarity of toner. When the first transfer bias voltage is applied to the intermediate transfer roller, the toner image formed on the surface of the photosensitive drum is transferred to the intermediate transfer belt  61 . Accordingly, the toner images formed on each of the photosensitive drums  40 K,  40 C,  40 M,  40 Y may be sequentially transferred onto the intermediate transfer belt  61  in an overlapping manner (e.g., the toner images are superimposed or layered), to form a composite toner image (e.g., a first transfer image). 
     Also, the transferring apparatus  60  may include a final transfer roller  63 . The final transfer roller  63  may face the driving roller  65  with the intermediate transfer belt  61  in between. 
     The final transfer roller  63  may be spaced apart from the intermediate transfer belt  61  while an image is being transferred from the photosensitive drum to the intermediate transfer belt  61 , and when the image on the photosensitive drum is fully transferred to the intermediate transfer belt  61 , the final transfer roller  63  may contact the intermediate transfer belt  61  at a predetermined pressure. When the final transfer roller  63  contacts the intermediate transfer belt  61 , the composite toner image carried on the intermediate transfer belt  61  may be transferred onto paper S. In order to transfer the toner image onto the sheet of paper S, a second transfer bias voltage may be applied onto the final transfer roller  63 . 
     When the second transfer bias voltage is applied to the final transfer roller  63 , the composite toner image (the first transfer image) formed on the intermediate transfer belt  61  is transferred to the paper S transferred by the paper supply apparatus  20  as a second transfer image. 
     In a process wherein a toner image is transferred to the photosensitive drum, then to the intermediate transfer belt  61 , and then to the paper, for example as described above, some toners (e.g., toner particles) may remain on the image carrier (the photosensitive drum or the intermediate transfer belt  61 ), and become waste toners. The image forming apparatus may include a cleaning member  100 , to remove waste toners (e.g., excess toner particles or residual toner particles) that remain on the photosensitive drum and/or on the intermediate transfer belt  61  in preparation for printing onto a next sheet of paper. 
     The cleaning member  100  may be arranged to contact each of the photosensitive drums  40 K,  40 C,  40 M,  40 Y and the intermediate transfer belt  61 . The cleaning member  100  may contact the image carrier (the photosensitive drum or the intermediate transfer belt  61 ) while applying a predetermined pressure thereto, to remove toner particles that remain on the photosensitive drums  40 K,  40 C,  40 M,  40 Y or the intermediate transfer belt  61  without having been transferred with the toner image. 
     The cleaning member  100  removes residual toner particles (waste toners) that remain on the outer circumferential surface of the photosensitive drum or the intermediate transfer belt  61  after transferring to the paper S has been performed by physical scraping. 
     The residual toner particles (waste toners) removed from the photosensitive drums  40 K,  40 C,  40 M,  40 Y and the intermediate transfer belt  61  by the cleaning member  100 , are transferred in a conveyance direction by rotation of a waste toner transfer auger  101  in the form of a screw, and the transferred waste toners may be collected at a waste toner collecting device  102 . For example, the waste toner transfer auger  101  may extend in a direction that is parallel to a rotational axis of the photosensitive drums  40 K,  40 C,  40 M,  40 Y or of the driven roller  67 , and which defines the conveyance direction. 
     The cleaning member  100  will be described in more detail further below. 
     The fuser  70  includes a heating roller  71  having a heat source, and a pressure roller  72  installed in an opposite direction to the heating roller  71 . When the paper S passes between the heating roller  71  and the pressure roller  72 , the toner image may be fixed onto the paper S by heat transferred from the heating roller  71  and pressure that operates between the heating roller  71  and the pressure roller  72 . 
     The paper eject apparatus  80  may include a paper eject roller  81  and a paper eject back-up roller  82 , and may eject the paper S that passed through the fuser  70  to the outside of the main body  10 . 
     Meanwhile, in illustrating and explaining  FIG. 1 , it was illustrated and explained that the image forming apparatus  1  includes a plurality of developing devices and photosensitive drums, and an intermediate transfer belt for color printing. In some examples, for example in an image forming apparatus that performs monochrome printing (e.g., an image forming apparatus that is limited to supporting black and white printing), there may be a single developing device and a single photosensitive drum, and an intermediate transfer belt may be omitted. 
       FIG. 2  is a front view illustrating a state wherein a cleaning member contacts an intermediate transfer belt  61  according to an example of the disclosure. 
     Referring to  FIG. 2 , the cleaning member  100  may be arranged to contact an image carrier  61 . 
     The image carrier  61  may carry an electrostatic latent image formed by the exposure apparatus  30  and/or a toner image formed by the developing device.  FIG. 2  illustrates an example wherein the image carrier is the intermediate transfer belt  61  that carries the toner image. In some examples, the image carrier may also be a photosensitive drum. 
     The configuration of the cleaning member  100  that removes waste toners from the photosensitive drum and the configuration of the cleaning member  100  that removes waste toners from the intermediate transfer belt  61  may be similar. Thus, for ease of understanding, the description of the cleaning member  100  arranged to contact the photosensitive drum is interchangeable with description of the cleaning member  100  arranged to contact the intermediate transfer belt  61 . 
     When a toner image is transferred to the intermediate transfer belt  61  or to the paper S in the printing process of the image forming apparatus  1 , some toners (toner particles) may remain on the photosensitive drum or the intermediate transfer belt  61 . Toners that remain on the photosensitive drum or the intermediate transfer belt  61  as described above become waste toners (e.g., excess toner particles or residual toner particles). Such waste toners may be removed by the cleaning member  100  that frictionally contacts the photosensitive drum or the intermediate transfer belt  61 . 
     The cleaning member  100  may be arranged to be adjacent to one side of the intermediate transfer belt  61 . For example, the cleaning member  100  may be arranged in a cleaning position which is a location within a predetermined distance from the intermediate transfer belt  61 . 
     The cleaning member  100  may include a blade  110  which contacts the intermediate transfer belt  61  while predetermined pressure is applied, and a support member  130  that supports the blade  110 . 
     The blade  110  contacts the surface of the intermediate transfer belt  61 , and blocks the surface such that remaining toners attached to the surface of the intermediate transfer belt  61  do not move beyond the blade  110  as the intermediate transfer belt  61  rotates. The blade  110  may comprise an elastomer material, for example, a urethane material. 
     One end of the blade  110  may be supported by the support member  130 , and the other end may be arranged to contact the surface of the intermediate transfer belt  61 . 
     An image area A defines an area on the intermediate transfer belt  61  to which a toner image may be transferred. The image forming apparatus  1  may intermediately transfer a toner image to the intermediate transfer belt  61 , and afterwards, the image forming apparatus  1  may finally transfer the toner image to the paper S that is transferred between the final transfer roller  63  and the intermediate transfer belt  61 . The image area A illustrated in  FIG. 2  indicates a maximum range of a toner image that can be transferred on the intermediate transfer belt  61 . 
     On the intermediate transfer belt  61 , a non-image area C defines an area of the intermediate transfer belt  61  where no toner image is transferred. The non-image area C is an area excluding the image area A to which a toner image is transferred, and may correspond to an outside area at both ends of the image area A. 
     On the intermediate transfer belt  61 , in addition to a toner image, a lubricating band B to accommodate an image for lubrication (or lubrication image), may be formed. The lubricating band B may function as a lubricant between the intermediate transfer belt  61  and the cleaning member  100 , and reduce friction between the cleaning member  100  and the image carrier  61 . 
     The image forming apparatus  1  may perform a lubricating operation of forming a toner image for lubrication (or lubrication toner image) on the image carrier  61  before printing the next page after completing printing of a page. 
     The exposure apparatus  30  may project light on the photosensitive drum and form an electrostatic latent image for lubrication (lubrication electrostatic latent image) in the form of a band in an axial direction of the photosensitive drum, and then the developing device may supply a toner to the electrostatic latent image for lubrication and form a lubricating band B (or lubrication band B) to which the electrostatic latent image for lubrication is transferred. 
     Some portions of the image for lubrication formed on the surface of the photosensitive drum may be transferred to the intermediate transfer belt  61  and form a lubricating band B on the intermediate transfer belt  61 . 
     The lubricating band B formed on the photosensitive drum is removed by the cleaning member  100  as the photosensitive drum rotates. In such examples, the lubricating band B may function as a lubricant between the photosensitive drum and the cleaning member  100 . 
     The lubricating band B formed on the intermediate transfer belt  61  is removed by the cleaning member  100  as the intermediate transfer belt  61  rotates. In such examples, the lubricating band B may function as a lubricant between the intermediate transfer belt  61  and the cleaning member  100 . 
     The lubricating band B may be formed in the form of a band that extends along an axial direction of the intermediate transfer belt  61 . The length of the lubricating band B formed in a longitudinal direction of the image carrier, may be the same as or longer than the length of the image area A in the longitudinal direction. The lubricating band B illustrated in  FIG. 2  indicates a maximum range of an image for lubrication (or lubrication image range) that can be transferred on the intermediate transfer belt  61 . When the image carrier is a photosensitive drum, the longitudinal direction corresponds to the direction of light projected onto the photosensitive drum. When the image carrier is the transfer belt, the longitudinal direction corresponds to a direction perpendicular to the proceeding direction (or conveying direction) of a printing paper (e.g., paper sheet S). 
     The length of the cleaning member  100  may be greater than the length of the lubricating band B. In this case, no lubrication image is applied between the outside area of the lubricating band B on the intermediate transfer belt  61  and the cleaning member  100 , and thus a non-lubricated area of the intermediate transfer belt  61  may become damaged due to friction with the cleaning member  100  or the cleaning member  100  may flip for example, due to friction in the absence of lubrication. 
     In addition, no image for lubrication is transferred at the edge area of the intermediate transfer belt  61  which is a non-lubricated area. Accordingly, frictional force may be generated between the cleaning member  100  and the intermediate transfer belt  61 , and due to increase of the torque of the intermediate transfer belt  61  according to the frictional force generated, the edge area of the intermediate transfer belt  61  which is a non-lubricated area may be broken, damaged or become worn out. 
     To prevent damage and wear in the edge area of the intermediate transfer belt  61 , the cleaning member  100  may be formed, where its cleaning angles with the intermediate transfer belt  61  are set to cause a contact pressure at both ends of the cleaning member  100  to be less than a contact pressure in the other portions of the cleaning member  100 . When the cleaning angle is reduced, the torque of the intermediate transfer belt  61  is reduced, and thus damage and wear in the edge area of the intermediate transfer belt  61  contacting both ends of the cleaning member  100  can be prevented or inhibited. 
     For example, both ends of the cleaning member  100  in the longitudinal direction may be formed to be bent toward the intermediate transfer belt  61 . 
     For example, portions  113  of the cleaning member  100  which are bent toward the intermediate transfer belt  61  may be formed to have a length that substantially corresponds to the non-image area C, and the other portion  111  of the cleaning member  100  may be formed to have a length corresponding to the image area A. 
     For example, in the axial direction of the intermediate transfer belt  61 , the image area A may have a length of 297 mm, and the lubricating band B may have a length of 313 mm. In this case, the blade  110  may be formed to have a length of 317 mm, and the portions  113  of the blade  110  bent in the direction of the intermediate transfer belt  61  (refer to  FIG. 3 ) may have a length of 10 mm, and the other portion  111  (refer to  FIG. 3 ) may have a length of 297 mm. 
     The specific configuration of the cleaning member  100  will be described in detail below. 
     In  FIG. 2 , an example wherein the cleaning member  100  is bent toward the intermediate transfer belt  61  was described. However, the disclosure is not limited thereto, and the cleaning member may be modified in numerous ways. In addition, a cleaning member arranged to contact the photosensitive drum may be formed to be bent toward the photosensitive drum. 
     In some examples, the cleaning member  100  may be formed such that the cleaning angles formed with the image carrier at both ends are greater than the cleaning angles formed with the image carrier in the other portions of the cleaning member  100 , and for example, both portions  113  of the cleaning member  100  may be formed to be bent toward the image carrier. 
       FIG. 3  is a perspective view of an example cleaning member  100 , and  FIG. 4  is an enlarged view of a portion indicated by IV in  FIG. 2 . 
     Referring to  FIGS. 3 and 4 , the cleaning member  100  may include a blade  110  which contacts the image carrier  61  while predetermined pressure is applied, and a support member  130  which supports the blade  110 . 
     The support member  130  may support the blade  110 , and it may be fixed to the main body  10  of the image forming apparatus  1 . 
     The blade  110  may contact the image carrier  61  and scrape off waste toners (or excess toner particles) that remain on the surface of the image carrier  61 . In addition, the blade  110  may be attached on one surface of the support member  130 . 
     The blade  110  may include a first portion  111  which is an intermediate portion (e.g., a main portion or center portion) along the longitudinal direction and a pair of second portions  113  which are located at the ends of the blade  110 . 
     The support member  130  may include a first surface  131  supporting the first portion  111 , and a second surface  133 , which supports the second portion  113 , is bent from both ends of the first portion  111 . 
     The first portion  111  may extend in parallel with the image carrier  61 , and, the second portion  113  may be bent from the first portion  111  toward the image carrier  61 . 
     The second portion  113  may be formed to extend from the first portion  111  at a predetermined angle θ, with respect to the first portion  111 . For example, the second portion  113  may form an angle θ of approximately 3° with the first portion  111 . 
     In some examples, the second portion  113  may be located to contact the image carrier  61  more closely relative to the first portion  111 . For example, the first portion  111  may extend from a first distal edge of the blade  110  toward the image carrier  61 , in which the distal edge extends substantially parallel to the image carrier  61 , and the second portion  113  may extend from a second distal edge toward the image carrier  61 , such that the second distal edge has at least a portion that is located at a shorter distance to the image carrier  61  than a distance between the second distal edge and the image carrier  61 . Accordingly, the second portion  113  contacts the image carrier  61  more closely relative to the first portion  111  contacting the image carrier  61 . The first distal edge of the blade  110  may be substantially aligned with the first surface  131  of the support member  130  and the second distal edge of the blade  110  may be substantially aligned with the second surface  133  of the support member  130 . In addition, in some examples, the first portion  111  may be spaced apart from the second portion  113 , by a predetermined distance. 
     In some examples, the first surface  131  supporting the first portion  111  and the second surface  133  supporting the second portion  113  may be spaced apart by a distance t of approximately 0.5 mm. 
     In some examples, the second surface  133  of the support member  130  supporting the second portion  113  may be formed to extend from the first surface  131  of the support member  130  supporting the first portion  111  at a predetermined angle θ. In addition, the second surface  133  may be formed to be located in a closer position to the image carrier  61  than the position of the first surface  131 . 
     One end of the blade  110  is fixed to the support member  130 , for example, with an adhesive such as a double-sided tape, a thermal adhesive film, or a primer for adhesion. 
     In some examples, one end of the blade  110  is fixed to the support member  130 , and the other end of the blade  110  that is not fixed is a free end, which may be elastically modified by external force. Accordingly, if the blade  110  is pressed to the surface of the image carrier  61 , the other end of the blade  110  is modified, and depending on the amount of modification, regular contact pressure may be applied on the image carrier  61 . 
     With further reference to  FIGS. 5 and 6 , a first cleaning angle α 1  between the first portion  111  of the blade  110  and the image carrier  61  is greater than a second cleaning angle α 2  between the second portion  113  of the blade  110  and the image carrier  61 . 
     The second portion  113  may be formed to have a length corresponding to the non-image area C. Also, the second portion  113  may be formed to be bent from the first portion  111  in an area wherein the non-image area C and the lubricating band B overlap with each other. 
     The length of the first portion  111  in the longitudinal direction may be formed to be the same as or longer than the length of the image area A, and the length of the second portion  113  in the longitudinal direction may be formed to be the same as or longer than the length of the lubricating band B. 
     In an example where the image area A extends along a length of 297 mm, and the lubricating band B extends along a length of 313 mm, the blade  110  may be formed as 317 mm, the first portion  111  may be formed as approximately 297 mm to correspond to the image area A, and the second portion  113  may be formed as approximately 10 mm. 
     The second portion  113  may be arranged to be adjacent to the image carrier  61 , and reduce the cleaning angle α formed with the image carrier  61 , and thereby reduce the torque of the image carrier  61  in the non-image area C wherein an image for lubrication is not formed. Accordingly, damage and wear in the edge area of the intermediate transfer belt  61  which is a non-lubricated area can be prevented or inhibited. 
       FIG. 5  is a schematic diagram for illustrating a cleaning angle between a cleaning member and an image carrier according to an example of the disclosure. 
     The cleaning angle α refers to an angle between the blade  110  modified by pressure and the image carrier  61 . An overlapping amount d may represent a theoretical depth by which the blade  110  would extend beyond the image carrier  61 . A set angle β refers to an angle between the blade  110  and the image carrier  61 . The cleaning angle α may be determined based on the overlapping amount d of the blade  110  with the image carrier  61  and the set angle β of the blade  110  according to the Formula 1 below.
 
α=β−arctan((3/2)*( d/l ))  [Formula 1]
 
     wherein α refers to the cleaning angle, β refers to the set angle, and d refers to the overlapping amount of the blade with the image carrier. 
     The cleaning angle α is a value which is a result of multiplying 3/2 with a value resulting from dividing the overlapping amount d of the blade  110  and the image carrier  61  by the length l of the free end, obtaining an arctangent value of the multiplication result, and then subtracting the arctangent value from the set angle β of the blade  110 . 
     The cleaning angle α may decrease as the overlapping amount d of the blade  110  and the image carrier  61  increases, and may increase as the overlapping amount d of the blade  110  and the image carrier  61  decreases. 
     Here, the overlapping amount d of the blade  110  and the image carrier  61  may be determined according to Formula 2.
 
 d=N*l   3 /(3* E*t )  [Formula 2]
 
     wherein d refers to the overlapping amount, N refers to an elastic force, l refers to the length of the free end of the blade, E refers to the Young&#39;s modulus, and t refers to the thickness of the blade. 
     The overlapping amount d of the blade  110  and the image carrier  61  refers to the depth of the overlapping portion of the blade  110  having elasticity with the image carrier  61 . Also, the overlapping amount d of the blade  110  and the image carrier  61  is a value which is a result of multiplying the elastic force N and the cube of the length l of the free end of the blade  110 , and then dividing the multiplied value by a product of the Young&#39;s modules E, multiplied by the thickness t of the blade  110 , multiplied by 3. 
     In the cleaning member  100  according to an example of the disclosure, the support member  130  of the non-image area C is formed in a shape of being bent toward the image carrier  61 , and accordingly, both ends of the blade  110  are formed to be bent toward the image carrier  61 , and the cleaning angle α of the non-image area C is formed to be less than the cleaning angles of the other areas, and thus durability and reliability of the image carrier  61  can be enhanced. 
       FIG. 6  is a cross-sectional view illustrating the cut sections taken along the lines I-I′ and II-II′ indicated in  FIG. 4 . 
     Referring to  FIG. 6 , the section cut along I-I′ is a cross-sectional view of the first portion  111  and was illustrated in a full line, and the section cut along II-II′ is a cross-sectional view of the second portion  113  and was illustrated in a dotted line. 
     Referring to the cross-sectional view of the first portion  111  illustrated in a full line, the first portion  111  and the intermediate transfer belt  61  may contact each other at a first contact pressure. Also, the first portion  111  and the intermediate transfer belt  61  may contact each other to have a first cleaning angle α 1 . 
     As the first portion  111  contacts the image area A of the intermediate transfer belt  61  and an area wherein the lubricating band B is formed, a lubrication operation between the first portion  111  and the intermediate transfer belt  61  becomes possible. Accordingly, the first cleaning angle α 1  between the first portion  111  and the intermediate transfer belt  61  may be set such that the blade  110  can easily remove a remaining image in a high temperature, high humidity environment, an office environment, and a low temperature environment. 
     For example, in the first portion  111 , the first cleaning angle α 1  may be set to be relatively large, and accordingly, the cleaning property of the blade  110  can be improved. 
     Meanwhile, referring to the dotted line illustrating the cross-sectional view of the second portion  113 , the second portion  113  and the intermediate transfer belt  61  may contact each other at second contact pressure. Also, the second portion  113  and the intermediate transfer belt  61  may contact each other to have a second cleaning angle α 2 . 
     If the second cleaning angle α 2  is reduced, the torque of the edge area of the intermediate transfer belt  61  contacting the second portion  113  is decreased, and thus damage and wear of the intermediate transfer belt  61  can be reduced. In addition, the edge of the intermediate transfer belt  61  is a non-lubricated area, and accordingly the edge of intermediate transfer belt  61  does not receive any toner nor any lubricating band. Therefore, friction between the intermediate transfer belt  61  and the blade  110  is increased. Thus, to reduce the torque of the edge area of the intermediate transfer belt  61 , the second portion  113  may be formed to contact the image carrier  61  more closely relative to the first portion  111 . 
     As the second portion  113  is formed to contact the image carrier  61  more closely, relative to the contact between the first portion  111  and the image carrier  61 , the overlapping amount with the intermediate transfer belt  61  in the second portion  113  is greater than the overlapping amount with the intermediate transfer belt  61  in the first portion  111 . 
     The second cleaning angle α 2  in the second portion  113  may be less than the first cleaning angle α 1  in the first portion  111 . 
     As the cleaning angle is reduced while the overlapping amount of the blade  110  and the intermediate transfer belt  61  is the same, the torque of the intermediate transfer belt  61  decreases more, and thus the cleaning torque that is generated during cleaning may be reduced. 
     For example, in a case where the cleaning angle is 12.1°, the torque of the intermediate transfer belt  61  is 342 g/cm, and the cleaning torque is measured as 67 g/cm. In another example where the cleaning angle is 11.6°, the torque of the intermediate transfer belt  61  is 335 g/cm, and the cleaning torque is measured as 60 g/cm. In another example where the cleaning angle is 8.4°, the torque of the intermediate transfer belt  61  is 332 g/cm, and the cleaning torque is measured as 57 g/cm. In another example where the cleaning angle is 4.3°, the torque of the intermediate transfer belt  61  is 332 g/cm, and the cleaning torque is measured as 30 g/cm. In another example without any cleaning member, the torque of the intermediate transfer belt  61  is 275 g/cm, and the cleaning torque is measured as 0 g/cm. 
     Through the above results, it can be figured out that the cleaning torque is reduced as the cleaning angle becomes smaller. 
     That is, as the cleaning torque in the second portion  113  contacting the non-lubricated area is smaller than the cleaning torque in the first portion  111 , damage and wear in the edge area of the intermediate transfer belt  61  can be reduced. 
     The overlapping amount of the second portion  113  is greater than the overlapping amount of the first portion  111 . Accordingly, the second contact pressure in the second portion  113  may be greater than the first contact pressure in the first portion  111 . 
     Accordingly, the second cleaning angle α 2  in the second portion  113  may be relatively small, but the second contact pressure with the intermediate transfer belt  61  in the second portion  113  may be relatively high, and thus the cleaning property of the second portion  113  can be enhanced. 
     The cleaning member  100  may include a second portion  113  which has a relatively small cleaning angle with the image carrier  61  on at both ends of the cleaning member  100 , and may thereby prevent damage and wear of the image carrier  61  in the non-lubricated area. Further, the second portion  113  may be advantageous for preventing damage and wear of the intermediate transfer belt  61  in a high temperature, high humidity environment wherein the torque of the intermediate transfer belt  61  increases. 
       FIG. 7  is a graph illustrating line pressure and cleaning angles according to each point of an example cleaning member. 
     Referring to  FIG. 7 , it is apparent that the cleaning angle and the line pressure between the cleaning member and the image carrier change according to the shape of the blade  110 . 
     Referring to the graph of cleaning angles, the first portion  111  may be formed to have a cleaning angle approximately equal to or less than 11° with the image carrier  61 . 
     The second portion  113  may be formed to have a cleaning angle within a range of approximately equal to or less than 11°, and equal to or greater than 5° with the image carrier  61 . Specifically, in the second portion  113 , both ends of the blade  110  which are closest to the image carrier  61  may be formed to have a cleaning angle approximately equal to or less than 6°, with the image carrier  61 . 
     The blade  110  may be formed such that the cleaning angle decreases from the first portion  111  to the second portion  113 . The cleaning torque may be decreased by forming the cleaning angle to be smaller at the ends of the blade  110 . Although the second portion  113  contacts the non-lubricated area of the image carrier  61 , the cleaning torque is low, and thus a phenomenon where the image carrier  61  is damaged due to friction or the cleaning member  100  may flip due to friction in the absence of lubrication may not occur. 
     Referring to the graph line of the line pressure, the first portion  111  may be formed to have line pressure of approximately 2 gf/mm with the image carrier  61 , and the second portion  113  may be formed to have line pressure within a range of approximately equal to or greater than 2 gf/mm and equal to or less than 4 gf/mm with the image carrier  61 . 
     As the second portion  113  contacting the non-image area C is formed to extend closer to the image carrier  61 , the cleaning angle between the blade  110  and the image carrier  61  in the non-image area C is relatively small, and the line pressure is relatively large. Accordingly, the cleaning torque applied to the ends of the image carrier  61  is low, and thus breakage, damage, and abrasion on both ends of the image carrier  61  can be prevented or inhibited. 
     In some examples of the cleaning member  100 , both ends of the blade  110  may be formed to be bend toward the image carrier  61 , and thus the overlapping amount with the image carrier  61  on both ends of the blade  110  may be changed. For example, both ends of the blade  110  may include the second portion  113  formed to bent in the direction of the image carrier  61 , and the overlapping amount with the image carrier  61  in the second portion  113  may be formed to be greater than the overlapping amount with the image carrier  61  in the first portion  111  that extends parallel with the image carrier  61 . 
     As the overlapping amount of the second portion  113  is formed to be greater, the second cleaning angle α 2  and the second contact pressure in the second portion  113  may be different from the first cleaning angle α 1  and the first contact pressure in the first portion  111 . 
     For example, the cleaning angle α 2  of the second portion  113  at both ends of the blade  110  may be less than the cleaning angle α 1  of the first portion  111  at the center portion of the blade  110 , and the first contact pressure may be less than the second contact pressure. 
     As described above, for the first portion  111  that contacts the image area A of the image carrier  61 , the cleaning angle is formed to improve the cleaning property, and for the second portion  113  that contacts the non-image area C of the image carrier  61 , the cleaning angle is formed to improve on durability and abrasion and prevention of a flipping phenomenon of the cleaning member, and accordingly, to prevent or inhibit breakage and abrasion at the ends of the image carrier, and to further prevent or inhibit a flipping phenomenon of the cleaning member. Through this, the lifespan of the image carrier and the cleaning member is increased, and reliability of the cleaning property of the cleaning member can thereby be enhanced. 
     It is to be understood that not all aspects, advantages and features described herein may necessarily be achieved by, or included in, any one particular example. Indeed, having described and illustrated various examples herein, it should be apparent that other examples may be modified in arrangement and detail.