Patent Publication Number: US-7917061-B2

Title: Image forming apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of Korean Patent Application No. 2008-0112061, filed on Nov. 12, 2008 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure relates generally to an image forming apparatus, and, more particularly, to an image forming apparatus having a cleaning device to remove waste developer remaining on an image carrier. 
     BACKGROUND OF RELATED ART 
     An image forming apparatus refers to an apparatus that prints an image on a printing medium. Broadly speaking, an image forming apparatus can be classified as a printer, a copying machine, a fax machine, a multi-function printer which has multiple functions of printing, scanning, copying and faxing, or the like. 
     An electrophotographic type image forming apparatus refers to a type of image forming apparatus that is particularly widely used and uses developer, such as e.g., toner to develop an electrostatic latent image into visible image. By way of a brief description, in a typical electrophotographic type image forming apparatus, a light is scanned on a photosensitive body previously charged to a predetermined electric potential to form an electrostatic latent image on the surface of the photosensitive body, which electrostatic latent image is then developed with developer to form the visible image. The visible image formed on the photosensitive body may be directly transferred onto a printing medium, or in some cases may be transferred onto a printing medium via an intermediate transfer body. The image transferred onto the printing medium is fused to the printing medium through a fusing process to complete the image forming process. 
     In the image forming operations generally discussed above, the developer on the photosensitive body or the intermediate transfer body is not necessarily completely transferred onto the intermediate transfer body or the printing medium, and some portion of the developer may remain on the photosensitive body or the intermediate transfer body even after the transfer of the image. Such residual waste developer may be removed from the photosensitive body or the intermediate transfer body by the use of a cleaning device. 
     A cleaning device may include a cleaning member in frictional contact with a surface of the image carrier, such as, for example, a photosensitive body or an intermediate transfer body, to collect the residual developer on the surface of the image carrier. 
     The cleaning device may be replaceable, and to that end, may be provided so that it can be removed from the image forming apparatus. 
     SUMMARY OF THE DISCLOSURE 
     In accordance with one aspect of the present disclosure, there may be provided an image forming apparatus that may include an image carrier, a detachable cleaning device and a first guide. The image carrier may have a surface on which a quantity of developer is carried. The detachable cleaning device may be detachably supported in the image forming apparatus, and may include a cleaning member that is configured to come into contact with the surface of the image carrier so as to remove developer from the surface of the image carrier. The detachable cleaning device may be configured to move along a first direction and a second direction non-parallel to the first direction during mounting and dismounting of the detachable cleaning device to and from the image forming apparatus. The second direction may be a direction along which the cleaning member moves toward or away from the surface of the image carrier. The first guide may include a restraining portion and a receiving portion. The restraining portion may be configured to limit the movement of the detachable cleaning device along the second direction toward the surface of the image carrier when the detachable cleaning device moves along the first direction, the receiving portion being configured to receive the restraining portion so as to allow the detachable cleaning device to move in the second direction, the restraining portion and the receiving portion being adapted to cooperate together such that the movement of the detachable cleaning device along the first direction initiates the movement of the detachable cleaning device along the second direction. 
     The image forming apparatus may further comprise a second guide configured to guide the detachable cleaning device to mow along the second direction toward the surface of the image carrier so as to bring the cleaning member into contact with the surface of the image carrier. 
     The first guide may include at least one guide body provided at the detachable cleaning device and at least one guide rail. The at least one guide body may each have a guide surface extending along the first direction. The at least one guide rail may each have a side wall opposing the guide surface. 
     The first guide may further comprise at least one guide protrusion protruding along the second direction from any first ones of the guide surface and the side walls. 
     The first guide may further comprise at least one guide recess formed on a second ones of the guide surfaces and the side walls opposing the first ones of the guide surfaces and the side walls. The at least one guide recess may be configured to receive therein a respective corresponding one of the at least one guide protrusion. 
     The at least one guide protrusion may include a first guide protrusion and a second guide protrusion. The first guide protrusion may be arranged to be spaced apart from the second guide protrusion, and may be longer in length with respect to the first direction than the second guide protrusion. 
     At least one of the at least one guide protrusion and the at least one guide recess includes a slanted surface slanted with respect to the first direction, the slanted surface promoting the movement of the detachable cleaning device along the second direction. 
     The at least one guide protrusion may include a first guide protrusion and a second guide protrusion. The second guide protrusion may be located downstream of the first guide protrusion with respect to a mounting direction of the detachable cleaning device along the first direction. The mounting direction being a direction in which the detachable cleaning device moves while being mounted in the image forming unit. The at least one guide recess may include a first guide recess and a second guide recess respectively corresponding to the first guide protrusion and the second guide protrusion. The first guide protrusion may be longer in length with respect to the first direction than the second guide protrusion. 
     The at least one guide body may include a first guide body provided on the top portion of the detachable cleaning device and a second guide body provided on the bottom portion of the detachable cleaning device. The at least one guide rail may include a first guide rail and a second guide rail respectively corresponding to the first guide body and the second guide body. 
     The second guide device may include at least one mounting guide protruding from the front end portion of the detachable cleaning device along the first direction. 
     The second guide device may further include a guide frame disposed to oppose the front end portion of the detachable cleaning device when the detachable cleaning device is mounted in the image forming apparatus. The guide frame may include at least one guide channel to receive the at least one mounting guide in such a manner to guide the detachable cleaning device to move along the second direction. 
     The at least one guide channel may each include a position determination portion and a slanted portion slanted toward the position determination portion. The position determination portion may be in contact with a corresponding one of the at least one mounting guide when the detachable cleaning device is mounted in its proper mounting position within the image forming apparatus. The slanted portion may be arranged to guide the mounting guide to the position determination portion. 
     The image forming apparatus may further comprise a fixing unit to securely fix the detachable cleaning device to its proper mounting position within the image forming apparatus. 
     According to another aspect of the present disclosure, an image forming apparatus may be provided to include a transfer unit, a cleaning device, at least one guide body, at least one guide rail, at least one guide protrusion and at least one guide recess. The transfer unit may include a transfer belt configured to transfer developer onto a printing medium. The cleaning device may be removably mounted to the transfer unit, and may be movable along a first direction in relation to the transfer unit. The at least one guide body may be provided at the cleaning device, and may have a side surface extending along the first direction. The at least one guide rail may have a side wall that extends along the first direction, and that opposes the side surface of a corresponding one of the at least one guide body. The at least one guide protrusion may protrude from a first one or more surfaces selected from any of the side surfaces of the at least ore guide body and any of the side walls of the at least one guide rail. The at least one guide recess may be formed on a second one or more surfaces that oppose the first one or more surfaces, and may be adapted to receive a corresponding one of the at least one guide protrusion. 
     The at least one guide protrusion may each include a slanted surface non-parallel and non-perpendicular to the first one or more surfaces. 
     The guide recess may includes a slanted surface non-parallel and non-perpendicular to the second one or more surfaces. 
     The at least one guide protrusion may include a first guide protrusion and a second guide protrusion arranged to be spaced apart from each other along the first direction. The at least one guide recess may include a first guide recess and a second guide recess respectively corresponding to the first guide protrusion and the second guide protrusion. The first guide protrusion may be longer in length in the first direction than the second guide recess. 
     The image forming apparatus may further comprise a mounting guide and a guide frame. The mounting guide may protrude from an upstream portion of the cleaning device with respect to a mounting direction in which the cleaning device moves along the first direction when being mounted to the transfer unit The guide frame may be disposed to oppose the upstream portion of the cleaning device when the cleaning device is mounted to the transfer unit. The guide frame may include a position determination portion and a slanted portion slanted toward the position determination portion. The position determination portion may come in contact with the mounting guide when the cleaning device is mounted in its proper mounting position in relation to the transfer unit. The slanted portion may be arranged to guide the mounting guide to the position determination portion 
     According to yet another aspect, an image forming apparatus may be provided to include an image carrier and a detachable cleaning device. The image carrier may be configured to carry thereon a developer image, an may have at least one rotational member configured to rotate about a rotational axis that extends along a first direction. The detachable cleaning device may be detachably supported in the image forming apparatus, and may include a cleaning member configured to come into contact with the image carrier so as to remove developer from the image carrier. The detachable cleaning device may be configured to move along the first direction and a second direction non-parallel to the first direction during mounting and dismounting of the detachable cleaning device to and from the image forming apparatus. The second direction may be the direction along which the cleaning member moves towards or away from the image carrier. The movement of the detachable cleaning device along the first direction may cause the detachable cleaning device to also move along the second direction. 
     The image forming apparatus may further comprise a guide mechanism that may be configured to guide the detachable cleaning device during mounting and dismounting of the detachable cleaning device to and from the image forming apparatus. The guide mechanism may comprise one or more protrusions spaced apart from each other and one or more recesses each corresponding to, and adapted to receive therein, the one of the one or more protrusions. The detachable cleaning device may be configured to move along the second direction toward the image carrier when each of the one or more protrusions is received in a corresponding one of the one or more recesses. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects and advantages of the disclosure will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a view illustrating a constitution of an image forming apparatus according to an embodiment of the present disclosure; 
         FIG. 2  is a perspective view illustrating a cleaning device mounted in a transfer unit of an image forming apparatus according to an embodiment of the present disclosure; 
         FIGS. 3 and 4  are sectional views illustrating respectively the mounted and dismounted states of the cleaning device according to an embodiment of the present disclosure; 
         FIG. 5  is a perspective view illustrating a cleaning device in according to an embodiment of the present disclosure; 
         FIG. 6  is a bottom view of the cleaning device shown in  FIG. 5 ; 
         FIG. 7  is a perspective view illustrating a first guide rail and a guide frame in the image forming apparatus according to an embodiment of the present disclosure; 
         FIG. 8  is a perspective view illustrating a second guide rail in the image forming apparatus according to an embodiment of the present disclosure; 
         FIG. 9  is a view illustrating a first guide body, the first guide rail, a mounting guide and the guide frame in the image forming apparatus according to an embodiment of the present disclosure; 
         FIG. 10  is a perspective view illustrating a mounting guide in the image forming apparatus according to an embodiment of the present disclosure; and 
         FIGS. 11 and 12  are views illustrating cleaning device mounting/dismounting operations in the image forming apparatus according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF SEVERAL EMBODIMENTS 
     Reference will now be made in detail to several embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. 
       FIG. 1  is a view illustrating a constitution of an image forming apparatus according to an embodiment of the present disclosure. 
     As shown in  FIG. 1 , an image forming apparatus  1  may comprise a main body  10 , a printing medium feeding unit  20 , a laser scanning unit  30 , an image forming unit  40 , a fusing unit  70  and a printing medium discharge unit  80 . 
     The main body  10  defines the exterior appearance of the image forming apparatus  1 , and may support therein various components. A cover  11  may be hingedly coupled to, or otherwise provided as capable of opening from, a surface of the main body  10  to provide an access to one or more components housed in the main body  10 . 
     The printing medium feeding unit  20  may include a cassette  21  to store printing media S, a pickup roller  22  that picks up the printing medium S, e.g., a sheet at a time, and feeding rollers  23  that feed the picked-up printing medium toward the image forming unit  40 . 
     The laser scanning unit  30  serves to irradiate light corresponding to image information to photosensitive bodies  51 K,  51 C,  51 M and  51 Y, to form electrostatic latent images on surfaces of the photosensitive bodies  51 K,  51 C,  51 M and  51 Y. 
     The image forming unit  40  may include a developing unit  50  that forms visible images by supplying developer, e.g., toner, to the electrostatic latent images formed on the photosensitive bodies  51 K,  51 C,  51 M and  51 Y, and a transfer unit  60  to transfer the visible images received from the photosensitive bodies  51 K,  51 C,  51 M and  51 Y to a printing medium. 
     The developing unit  50  may include four developing devices  50 K,  50 C,  50 M and  50 Y, in which developer of different color from each other, e.g., black (K), cyan (C), magenta (M) and yellow (Y), are respectively stored. 
     The respective developing devices  50 K.  50 C,  50 M and  50 Y may each include a charger  52  a developer storage part  53  developer conveying members  54  and a developing member  55 . Prior to forming the electrostatic latent images on the photosensitive bodies  51 K,  51 C,  51 M and  51 Y, the respective chargers  52  charge the surfaces of the photosensitive bodies  51 K,  51 C,  51 M and  51 Y to a uniform potential level. The exposure to the light from the laser scanning unit  30  results in the formation of the electrostatic latent images on the uniformly charged surfaces of the photosensitive bodies  51 K,  51 C,  51 M and  51 Y. The developer stored in the developer storage parts  53  may be conveyed to the respective developing members  55  by the developer conveying members  54 , which may then be in turn supplied by the developing members  55  to the electrostatic latent images on the photosensitive bodies  51 K,  51 C,  51 M and  51 Y, thereby forming visible developer images. 
     The transfer unit  60  may include a transfer belt  61 , a driving roller  62 , a supporting roller  63 , tension rollers  64  and first transfer rollers  65 . The transfer belt  61  rotates while being supported by the driving roller  62 , the supporting roller  63  and the tension rollers  64 . The transfer belt  61  serves as an image carrier which holds a developer image to be transferred onto a printing medium. In alternative embodiments, it is also possible that the developer images on the photosensitive bodies  51 K,  51 C,  51 M and  51 Y are transferred to the printing medium directly from the photosensitive bodies without the intermediary transfer to the transfer belt  61 . In such embodiments, the printing medium may be guided to come into a direct contact with the photosensitive bodies  51 K,  51 C,  51 M and  51 Y. 
     The respective visible images formed on the photosensitive bodies  51 K.  51 C,  51 M and  51 Y are transferred onto the transfer belt  61  by the first transfer rollers  65 , overlapping with each other. The image on the transfer belt  61  may be transferred onto the printing medium which is supplied from the printing medium feeding unit  20  as the printing medium passes between the second transfer roller  45  and the transfer belt  61 . 
     The printing medium having passed through the transfer unit  60 , and thus bearing a developer image thereon, may move to the fusing unit  70 . The fusing unit  70  may include a heating roller  71  and a press roller  72 . The image being carried on the printing medium becomes used to the printing medium by the application of the heat and pressure as the printing medium passes between the heating roller  71  and the press roller  72 . 
     The printing medium passing through the fusing unit  70  is guided to the printing medium discharge unit  80 , and then is discharged outside the main body  10  by a discharge roller  81 . 
     When the image is transferred onto the printing medium, the developer on the transfer belt  61  may not completely transferred onto the printing medium, but some portion of the developer may remain on the transfer belt  61  after the transfer of the image onto the printing medium. The residual waste developer may be removed from the transfer belt  61  by a cleaning device  100 . 
       FIG. 2  is a perspective view illustrating a cleaning device mounted, by way of an example, to a transfer unit of an image forming apparatus according to an embodiment of the present disclosure.  FIGS. 3 and 4  are sectional views illustrating the relevant portions of the cleaning device and the transfer unit shown in  FIG. 2 .  FIG. 3  shows a state in which the cleaning device is mounted to the transfer unit, and in which the cleaning member is in contact with the transfer belt.  FIG. 4  shows a state in which the cleaning member is separated from the transfer unit. 
     Referring to  FIGS. 2 to 4 , the transfer unit  60  may include a transfer unit frame  66 . The cleaning device  100  may be detachably mounted to the transfer unit frame  66 . Therefore, when the cleaning device  100  needs to be replaced or repaired, the cleaning device  100  can be removed from the transfer unit  60 . 
     The image forming apparatus  1  according to an embodiment may include a first guide device  200  and a second guide device  300  (refer to  FIGS. 7 and 10 ) to guide the mounting/dismounting of the cleaning device  100 . During the mounting/dismounting operation of the cleaning device  100  to/from the transfer unit  60 , the first guide device  200  guides the cleaning device  100  such that the cleaning device  100  can move while the separation between the cleaning member  120  of the cleaning device  100  and the transfer belt  61  may be maintained. For example, during the mounting operation of the cleaning device  100  to the transfer unit  60 , the second guide device  300  guides the cleaning device  100  such that the cleaning member  120  comes into contact with the transfer belt  61  upon the completion of the mounting operation. The first guide device  200  and the second guide device  300  will be described in greater detail later. 
     Referring now to  FIGS. 3 and 4 , the cleaning device  100  may include a frame  110 , a cleaning member  120 , a shielding member  130  and a waste developer conveying member  140 . 
     A waste developer storage part  112  may be provided inside the cleaning device frame  110 . The cleaning member  120  and the shielding member  130  may be mounted in proximity to the waste developer storage part  112 . According to an embodiment, the cleaning member  120  may be configured as a cleaning blade  121 . The cleaning blade  121  has an end portion which makes a frictional contact with the transfer belt  61  so as to carry out a raking, or otherwise collection, of the residual developer from the surface of the transfer belt  61 . The shielding member  130  is disposed to oppose the cleaning member  120  in the vertical direction, so as to prevent the waste developer from leaking out from the cleaning device  100 . 
     The waste developer removed from the transfer belt  61  by the cleaning member  120  maybe stored in the waste developer storage part  112 . The waste developer conveying member  140  may be mounted in the waste developer storage part  112 , and may convey the waste developer stored in the waste developer storage part  112  to a waste developer discharge port  114  (refer to  FIG. 6 ). The waste developer discharge port  114  may communicate with a waste toner container (not shown), which may be mounted inside the main body  10 . According to an embodiment the waste developer discharged through the waste developer discharge port  114  may be stored in the waste toner container for subsequent disposal. 
     As shown in  FIGS. 2 to 4 , the cleaning device  100  is mounted or removed to/from the transfer unit  60  by moving in a first direction (A direction) and a second direction (B direction). The first direction A refers to a direction in which the cleaning device  100  moves along the width direction (W direction) of the transfer belt  61 . The second direction B refers to the direction in which the cleaning member  120  moves towards or away from the transfer belt  61 . Hereinafter, the first direction may taught to be further divided into a mounting direction and a removing direction, where the mounting direction is denoted as the A 1  direction while the removing direction is denoted as the A 2  direction as indicated in  FIG. 2 . The second direction may also be considered to include a contacting direction (i.e., the direction in which the cleaning member  120  moves towards the transfer belt  61 ) and a separating direction (i.e., the direction in which the cleaning member  120  moves away from the transfer belt  61 ). The contacting direction is denoted as the B 1  direction while the separating direction is denoted as the B 2  direction as shown in  FIGS. 3 and 4 . 
       FIG. 5  is a perspective view illustrating a cleaning device according to an embodiment of the present disclosure.  FIG. 6  is a bottom view of the cleaning device shown in  FIG. 5 .  FIG. 7  is a perspective view illustrating a first guide rail and a guide frame, which may be provided in an image forming apparatus, according to an embodiment of the present disclosure.  FIGS. 8 and 9  illustrate first guide rail, a second guide, a first guide body, the first guide rail, a mounting guide and the guide frame, one or more of which may be included in an image forming apparatus according to an embodiment of the present disclosure. 
     As shown in  FIGS. 5 to 8 , the first guide device  200  (refer to  FIG. 2 ) may include a restraining unit(s)  210  (see  FIG. 5 ) and a receiving unit(s)  220  (see  FIG. 7 ). The restraining unit  210  restricts the movement of the cleaning device  100  in the second direction (B) when the cleaning device  100  moves in the first direction (A). The receiving unit(s)  220  receives the restraining unit(s)  210  so as to allow the cleaning device  100  to move in the second direction (B) to complete the mounting of the cleaning device  100 . 
     Due to the restriction by the restraining unit  210  in the movement of the cleaning device  100  in the second direction, the cleaning device  100  may be moved along the first direction while maintaining a separation between the cleaning member  120  and the transfer belt  61 . Accordingly, possible damages to the transfer belt  61  from the friction with the cleaning member  120  may be mitigated. The receiving unit(s)  220  releases the restraint by the restraining unit(s)  210  by receiving therein the restraining unit(s)  210  to allow the completion of the mounting of the cleaning device  100 , and to allow the cleaning member  120  to come into a contact with the transfer belt  61 . 
     The first guide device  200  may include first and second guide bodies  230  and  240  provided at the cleaning device  100 , and first and second guide rails  250  and  260  provided corresponding to the first and second guide bodies  230  and  240 . Although it has been described that this embodiment employs two guide bodies and two guide rails, the embodiment can be modified to employ any number of guide bodies and/or guide rails, for example, a single guide body with a single guide rail could also be used. 
     As shown in  FIGS. 2 ,  7  and  8 , the first guide body  230  may be provided on the top portion of the cleaning device frame  110  while the second guide body  240  may be provided on the bottom portion of the cleaning device frame  110 . The first guide body  230  and the second guide body  240  may be formed integrally with the cleaning device frame  110 , or may be formed as separate bodies that are coupled to the cleaning device frame  110 . 
     The first guide rail  250  may correspond to, and be disposed above, the first guide body  230  to guide the first guide body  230  during the movement of the cleaning device  100 . The second guide rail  260  may correspond to, and be disposed below, the second guide body  240  to guide the second guide body  240 . According to an embodiment, the first guide rail  250  may be mounted, for example, to the transfer unit frame  66  while the second guide rail  260  is mounted to the main body  10 . In alternative embodiments, each of the first guide rail  250  and the second guide rail  260  may be mounted to any of the transfer unit frame  66 , the main body  10  or any other suitable structure within the main body  10 . 
     Referring to  FIGS. 5 ,  6  and  9 , the first guide body  230  may include guide surfaces  231  and  232  extending along the first direction (A), and respectively opposing the two side walls  251  and  252  of the first guide rail  250 . The two guide surfaces  231  and  232  of the first guide body  230  are configured to be able to be disposed between the two side walls  251  and  252  of the first guide rail  250 . 
     In the embodiment depicted in  FIGS. 5-9 , by way of an illustrative example, two restraining units  210  are provided, each including a guide protrusion, such as, for example, a first guide protrusion  211  and a second guide protrusion  212 , respectively, as illustrated in the figures. The first guide protrusion  211  and the second guide protrusion  212  protrude in the second direction toward the side wall  251  from the guide surface  231  of the first guide body  230 , which is disposed nearer to the transfer belt  61  than the guide surface  232 . The receiving units  220 , according to the illustrated embodiment, may include a first guide recess  221  and a second guide recess  222  formed on the side wall  251  of the first guide rail  250 . The first guide recess  221  and the second guide recess  222  are arranged to be capable of receiving the first guide protrusion  211  and the second guide protrusion  212 , respectively. 
     While the cleaning device  100  moves in the first direction, the first guide protrusion  211  and the second guide protrusion  212  guide the position of the cleaning device  100  such that the cleaning member  120  does not contact the transfer belt  61 . When the cleaning device  100  is positioned at the proper mounting position with respect to the first direction CA), the first guide recess  221  and the second guide recess  222  receive the first guide protrusion  211  and the second guide protrusion  212 , respectively, to complete the process of mounting the cleaning device  100  in the image forming apparatus. 
     The first guide protrusion  211  and the second guide protrusion  212  may have different lengths from each other with respect to the first direction. The first guide recess  221  and the second guide recess  222  may have different lengths from each other in the first direction, correspondingly respectively to the first guide protrusion  211  and the second guide protrusion  212 . 
     With the unequal lengths configuration described above, for example, if the first guide protrusion  211  is longer than the second guide recess  222  in the first direction, during the movement of the cleaning device  100  in the A 1  direction during mounting, the first guide protrusion  211  can be prevented from being seated in the second guide recess  122 . 
     The first guide protrusion  211  and the second guide protrusion  212  may have first slanted surfaces  211   a  and  212   a  which are slanted from the guide surface  231 . The first guide recess  221  and the second guide recess  222  may have second slanted surfaces  221   a  and  222   a  corresponding to the first slanted surfaces  211  a and  212   a . When the cleaning device  100  moves in the A 2  direction, the first slanted surfaces  211  a and  212   a  and the second slanted surfaces  221  a and  222   a  serve to provide a smooth exit by the first guide protrusion  211  and the second guide protrusion  212  from the first guide recess  221  and the second guide recess  222 . 
     The first guide protrusion  211  and the second guide protrusion  212  have third slanted surfaces  211   b  and  212   b  positioned opposite to the first slanted surfaces  211   a  and  212   a  in the first direction. The third slanted surfaces  211   b  and  212   b  serve to guide the first guide protrusion  211  and the second guide protrusion  212  to move smoothly along the first guide rail  250 . 
     As shown in  FIGS. 6 and 8 , similar to the first guide body  230 , the second guide body  240  may have guide surfaces  241  and  242 , a first guide protrusion  213  and a second guide protrusion  214 . Similar to the first guide rail  250 , the second guide rail  260  may have side walls  261  and  262 , a first guide recess  223  and a second guide recess  224 . Since the constitution of the second guide body  240  and the second guide rail  260  can be easily understood from the constitution of the first guide body  230  and the first guide rail  250 , the same explanation will not be repeated. 
       FIG. 10  is a perspective view illustrating a mounting guide in an image forming apparatus according to an embodiment of the present disclosure. 
     Referring now to  FIGS. 7 ,  9  and  10 , the image forming apparatus  1  may include a second guide device  300  for guiding the cleaning device  100  in the second direction during the mounting/dismounting of the cleaning device  100 . 
     The second guide device  300  may include a mounting guide(s)  310 , which may be formed at the front end portion  101  of the cleaning device  100  in the mounting direction (A 1  direction) of the cleaning device  100 , and a guide frame  320  (see  FIG. 7 ) disposed to face the mounting guide(s)  310 . 
     The mounting guide(s)  310  may extend from the front end portion  101  of the cleaning device  100  along the first direction. When the cleaning device  100  reaches the proper mounting position, the mounting guide(s)  310  may become coupled to the guide channel(s)  330  formed on the guide frame  320 . 
     When the mounting of the cleaning device  100  in the first direction is completed, the guide channel  330  receives the mounting guide  310  as the cleaning device  100  moves in the second direction, and thereby determines the mounting position of the cleaning device  100 . The guide channel  330  may include a position determination portion  331  and a slanted portion  332 . The position determination portion  331  is coupled to the mounting guide  310  to determine the mounting position of the cleaning device  100 . The slanted portion  332  is slanted toward the position determination portion  331  to guide the mounting guide  310  to the position determination portion  331 . 
     As shown in  FIG. 2 , a fixing unit  150  may be provided at the rear end portion  102  with respect to the mounting direction (A 1  direction) of the cleaning device  100 , so as to fix the cleaning device  100  to the transfer unit  60 . The fixing unit  150  may include a head part  151  and a fixing part (not shown) extending from the head part  151  toward the transfer unit  60 . The fixing part may be formed to be screw-engaged with the transfer unit frame  66 , for example. 
     Hereinafter, the mounting/dismounting operation of the cleaning device  100  will be described with reference to  FIGS. 11 and 12 , with reference primarily to the first guide body  230  and the first guide rail  250 . It should be understood that the second guide body  240  and the second guide rail  260  behave in substantially the same manner during the mounting/dismounting operation of the cleaning device  100 . 
     The removing operation of the cleaning device  100  will firstly be explained with reference to  FIGS. 2 ,  9  and  11 . As shown in  FIGS. 2 and 9 , from the state that the cleaning device  100  is mounted in the transfer unit  60 , the engagement between the fixing unit  150  and the transfer unit  60  may be released by, for example, rotating the head part  151  of the fixing unit  150 . Thereafter, the cleaning device  100  may be pulled, so that the cleaning device  100  moves in the A 2  direction, and become separated from the transfer unit  60 . 
     When the cleaning device  100  starts to move in the A 2  direction, as shown in  FIG. 11 , the first guide protrusion  211  and the second guide protrusion  212  of the first guide body  230  escape from the first guide recess  221  and the second guide recess  222 . At this time, the first slanted surfaces  211   a  and  212   a  of the first and second guide protrusions  211  and  212  and the second slanted surfaces  221   a  and  222   a  of the first and second guide recesses  221  and  222  assist the first and second guide protrusions  211  and  212  moving out of the first and second guide recesses  221  and  222 . While the first and second guide protrusions  211  and  212  escape from the first and second guide recesses  221  and  222 , the cleaning device  100  moves in the B 2  direction. Accordingly, as shown in  FIG. 4 , the cleaning member  120  of the cleaning device  100  is separated from the transfer belt  61 . In such a state, the cleaning device  100  is farther pulled in the A 2  direction, and is thereby separated from the transfer unit  60 . 
     The embodiments described above may advantageously allow both the separation of the cleaning member  120  from the transfer belt  61  and the removal of the cleaning device  100  from the transfer unit  60  by the same pulling of the cleaning device  100  in the A 2  direction. 
     The mounting operation of the cleaning device  100  will now be explained with reference to  FIG. 12 . If a user pushes the cleaning device  100  in the A 1  direction, the cleaning device  100  moves along the A 1  direction to be mounted in the transfer unit  60 . When the cleaning device  100  moves in the A 1  direction, the first and second guide protrusions  211  and  212  of the first guide body  230  restricts the movement of the cleaning device  100  in the B 1  direction, thus maintaining the separation between the cleaning member  120  and the transfer belt  61  as shown in  FIG. 4 . 
     When the cleaning device  100  reaches the mounting position with respect to the first direction, the first and second guide protrusions  211  and  212  of the first guide body  230  are positioned to correspondingly oppose the first and second guide recesses  221  and  222  of the first guide rail  250 . In such position, the cleaning device  100  is able to move in the B 1  direction. 
     As the mounting guide  310  of the second guide device  300  are received into the guide channel  330  of the guide frame  320 , the slanted portion  332  of the guide channel  330  guides the mounting guide  310  so that the cleaning device  100  moves in the B 1  direction. As the cleaning device  100  moves in the B 1  direction, the first and second guide protrusions  211  and  212  are received in the first and second guide recesses  221  and  222 , and the cleaning member  120  of the cleaning device  100  comes into contact with the transfer belt  61 . 
     When the mounting guide  310  engages the position determination portion  331  of the guide channel  330 , as shown in  FIG. 9 , the mounting of the cleaning device  100  is completed. In such a state, the cleaning device  100  may be fixed to the transfer unit  60  by using the fixing unit  150 . 
     According to an aspect of the present disclosure, several embodiments described above have the advantage of enabling the mounting of the cleaning device  100  and the positioning of the cleaning member  120  in relation to the transfer belt  61  may both be achieved only with the single pushing of the cleaning device  100  in the A 1  direction. 
     Although several embodiments were described as employing two guide protrusions and two guide recesses, it should be readily apparent that the number of guide protrusions and guide recesses are not limiting, and that, in alternative embodiments, any number of guide protrusions and guide recesses, one or three or more of guide protrusions and/or guide recesses may be employed. 
     Although it has been described that the guide protrusions are provided at the guide body of the cleaning device and the guide recesses are formed at the guide rail, it should be readily understood that the opposite arrangement is also possible, that is, for example, the guide protrusions can be provided at the guide rail and the guide recesses can be formed at the guide body of the cleaning device. 
     As is apparent from the above disclosure, according to an aspect thereof, an image forming apparatus may be provided to include a structure capable of allowing convenient mounting or dismounting of the cleaning device, which reduces the likelihood of damage to the image carrier, which may result from the contact with the cleaning member of the cleaning device during the cleaning device mounting/dismounting. 
     Although several embodiments of the present disclosure have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the inventive aspects of the present disclosure, the scope of which is defined in the claims and their equivalents.