Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit under 35 U.S.C. § 119 (a) of Korean Patent Application No. 2004-68269, filed on Aug. 28, 2004, the entire disclosure of which is hereby incorporated by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention generally relates to a developing unit of an image forming apparatus. More particularly, the present invention relates to an image forming apparatus having a developing unit with a foldable handle. 
   2. Description of the Related Art 
   As shown in  FIG. 1 , a general image forming apparatus  1  includes a paper cassette  10 , a transport unit  20 , a developing unit  30 , a transfer unit  40 , a fixing unit  50 , and a paper discharging unit  60 . 
   The paper cassette unit  10  stores a plurality of sheets of paper. The transport unit  20  transports the sheets of paper stored in the paper cassette unit  10  to the developing unit  30 . The paper cassette unit  10  includes a pickup roller  11 . The transport unit  20  includes a plurality of pairs of transport rollers  21  and  22 . 
   The developing unit  30  includes a photosensitive body  32  to receive light from an exposing unit  31  to form an electrostatic latent image, and a developing case  34  pivotably supporting the photosensitive body  32 . The developing case  34  includes a developer container  33  containing a developer for developing the electrostatic latent image formed on the photosensitive body  32 . 
   The transfer unit  40  transfers a visible image formed on the photosensitive body  32  to a sheet of paper. 
   The fixing unit  50  passes the sheet of paper to which the visible image has been transferred to apply heat and pressure to the sheet of paper. Thus, the visible image is fused and fixed onto the sheet of paper. 
   The paper discharging unit  60  discharges the sheet of paper which has passed through the fixing unit  50 . 
   The developing unit  30  preferably is replaced when the developer contained in the developer container  33  is exhausted. For this purpose, the general image forming apparatus includes a cover  2  that can be opened and closed. The developing unit  30  includes a handle  35  for easily handling the developing unit  30 . In general, the handle  35  is pivotably hinged on the developing case  34  and is preferably fixed on the developing case  34 . 
   However, in the above-described developing unit  30  of the general image forming apparatus, the handle  35  protrudes farther than an outer periphery of the developing case  34 . Thus, when the developing unit  30  is packaged, the size of the developing unit  30  increases. Also, the handle  35  is limitedly used to remove the developing unit  30 . Thus, the handle  35  is non-economical in terms of its utility value compared to its size. 
   Accordingly, there is a need for an image forming apparatus having a developing unit with a foldable multipurpose handle that does not protrude substantially beyond the periphery of the developing unit when being folded so as to reduce the size of the developing unit and which may also be used as a paper guide. 
   SUMMARY OF THE INVENTION 
   An aspect of the present invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present invention is to provide a developing unit having a foldable multipurpose handle which does not protrude substantially beyond the periphery of the developing unit when being folded so as to reduce the size of the developing unit. Moreover, the foldable multi-purpose handle is also used as a paper guide as well as a handle when being unfolded. 
   According to an aspect of the present invention, there is provided a developing unit of an image forming apparatus including an image forming unit including at least one of a photosensitive body. A developing roller developing a developer on the photosensitive body. A case protecting the image forming unit and a handle installed at the case to handle the developing unit. Accordingly, the handle pivots to a first position attached to the case and a second position opposite to the first position. 
   Preferably, the first position is a storage position, and the second position is a use position. The use position is preferably orientated at an angle of about 180° from the storage position. 
   It is also preferable that the handle has a smaller width than a width of the case. Moreover, it is preferably that the handle is installed at an approximate center of the case to be folded by a hinge. 
   The handle preferably includes a guide plate, and a gripping unit bent from an end of the guide plate. A plurality of guide ribs may be formed on a back surface of the guide plate. 
   According to another aspect of the present invention, there is provided an image forming apparatus including a body frame with a developing unit mounting unit. A paper feeding unit is disposed in the body frame and comprises a plurality of sheets of paper. An auxiliary paper feeding unit is installed on the body frame to feed sheets of paper having various sizes and includes a paper path partially overlapping with a paper path of the paper feeding unit. A transfer unit is provided for transferring a sheet of paper picked up by the paper feeding unit or the auxiliary paper feeding unit and a developing unit is attachable to or detachable from the developing unit mounting unit of the body frame. The developing unit preferably includes an image forming unit with at least one of a photosensitive body and a developing roller developing a developer on the photosensitive body. It is also preferable to provide a case to protect the image forming unit and a handle installed on the case to guide a sheet of paper fed from the auxiliary paper feeding unit. 
   The handle preferably pivots to a first position attached to the case and a second position opposite to the first position. The first position is preferably a storage position, and the second position is preferably a use position. The use position may be advantageously disposed at an angle of about 180° from the storage position. 
   It is also preferably that the handle has a smaller width than a width of the case and is installed in an approximate center of the case to be folded by a hinge. 
   The handle preferably includes a guide plate, and a gripping unit bent from an end of the guide plate. A plurality of guide ribs may be formed on a back surface of the guide plate. 
   The handle may be unfolded so that a height of the back surface of the guide plate does not exceed about 60 mm from a bottom. 
   The developing unit may also be removed in an identical direction to a direction along which the paper feeding unit is removed. 
   The developing unit mounting unit may also include a guide rail slanting toward the direction along which the developing unit is removed and a shaft supporter on which a pivot shaft of the photosensitive body may be placed. 
   The developing unit mounting unit may be positioned substantially under a fixing unit. 
   The auxiliary paper feeding unit may also be installed between the developing unit and the paper feeding unit. 
   Accordingly, the handle may be foldably installed on the developing unit. Thus, when the developing unit is packaged, the size of the developing unit may be reduced. Also, an external impact on the developing unit may be relieved. As a result, the durability of the developing unit is improved. In addition, the handle can be used to mount and remove the developing unit. Moreover, when the handle is installed on the developing unit, the handle is unfolded for use as a paper guide as well as a handle. Accordingly, the utility value of the handle is improved. 
   Other objects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses preferred embodiments of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other objects, and features, and advantages of certain embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
       FIG. 1  illustrates a general developing unit and an image forming apparatus including the general developing unit; 
       FIG. 2  illustrates a developing unit including a foldable handle and an image forming apparatus including the developing unit in accordance with an embodiment of the present invention; 
       FIG. 3  illustrates removal of the developing unit including the foldable handle from the image forming apparatus; 
       FIG. 4  illustrates an example of folding the foldable handle of the developing unit shown in  FIG. 3 ; and 
       FIG. 5  is a perspective view of the developing unit shown in  FIG. 4 . 
   

   Throughout the drawings, the same drawing reference numerals will be understood to refer to the same elements, features, and structures. 
   DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
   The matters defined in the description such as a detailed construction and elements are provided to assist in a comprehensive understanding of the embodiments of the invention. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. Also, descriptions of well-known functions and constructions are omitted for conciseness. 
   As shown in  FIGS. 2 and 3 , an image forming apparatus includes a body frame  100 , a paper feeding unit  110 , a transfer unit  120 , a developing unit  130 , and a fixing unit  140 . In the body frame  100 , an auxiliary paper feeding unit  111  is installed between the developing unit  130  and the paper feeding unit  110  to feed sheets of paper having various sizes. The structures and functions of the body frame  100 , the paper feeding unit  110 , the transfer unit  120 , the developing unit  130 , and the fixing unit  140  are substantially the same as those of the components of the general image forming apparatus and thus a detailed description of these components is omitted for clarity and conciseness. Hereinafter, the developing unit  130  and a handle  200  foldably installed on the developing unit  130  will be described. 
   The developing unit  130  is attachable to or detachable from the body frame  100 . Thus the developing unit  130  may be detached from the body frame  100  in instances such as when a developer is exhausted or a sheet of paper is jammed. The developing unit  130  includes a photosensitive body  131 , a case  130   a  to protect an image forming unit. Moreover, a developing roller (not shown) is provided to supply a powdered developer to the photosensitive body  131  and the handle  200  is installed on the case  130   a.    
   The case  130   a  pivotably supports the photosensitive body  131  on which an electrostatic latent image is formed by light irradiated from an exposing unit  105 . The developing unit  130  develops the powdered developer on the photosensitive body  131  and is preferably formed of an outer case or frame of the developing unit  130 . A pivot shaft  132  preferably protrudes to the outside of the case  130   a  to power the photosensitive body  131 . The pivot shaft  132  guides the developing unit  130  toward a developing unit mounting unit  101  installed on the body frame  100 . 
   As shown in  FIGS. 2 and 3 , the developing unit mounting unit  101  is positioned substantially lower than the fixing unit  140  so as to position the developing unit  130  under the fixing unit  140 . The developing unit mounting unit  101  includes a guide rail  102  and a shaft supporter  103 . 
   The guide rail  102  supports both ends of the pivot shaft  132  and guides the developing unit  130  to a mounting position thereof. The guide rail  102  preferably slants from the mounting position as shown in  FIGS. 2 and 3 . 
   The shaft supporter  103  is substantially concave as shown in  FIGS. 2 and 3 . Thus, both ends of the pivot shaft  132  are put on the shaft supporter  103 . Additionally, a power transmitting unit  133  (shown in  FIG. 3 ) and may be installed on the shaft supporter  103 . 
   The developing unit  130  may be removed from the image forming apparatus in a direction indicated by arrow A as shown in  FIG. 3 . This direction is the same direction along which the paper feeding unit  110  is removed. 
   The handle  200  preferably has a smaller width than that of the case  130   a . The handle  200  is foldably combined with an approximate center of the case  130   a  by a hinge  201 . Thus, the handle  200  may pivot on the hinge  201  from its storage position  230  attached to the case  130   a  to a use position to which the handle  200  pivots about 180° from the storage position  230  as shown in  FIG. 5 . The handle  200  includes a guide plate  210  and a gripping unit  220 . 
   As shown in  FIG. 5 , a plurality of guide ribs  211  are formed on the back surface of the guide plate  210 . The guide ribs  211  guide a transport path of a sheet of paper P fed from the auxiliary paper feeding unit  111 . 
   The gripping unit  220  is preferably bent from an end of the guide plate  210  and so that the gripping unit may be conveniently pulled by a user. 
   The operation of the image forming apparatus including the developing unit  130  and the foldable handle  200  will now be described. 
   As shown in  FIG. 2 , the developing unit  130  is mounted on the body frame  100  with the handle  200  unfolded. If a sheet of paper is jammed or a developer is exhausted, the developing unit  130  is removed from the body frame  100  as shown in  FIG. 3 . In other words, if the user grips and pulls the gripping unit  220  of the handle  200  in the direction indicated by a thick arrow shown in  FIG. 3 , the pivot shaft  132  is released from the shaft supporter  103  and is removed along the guide rail  102  toward a front portion of the body frame  100 . That is, in an identical direction to a direction along which the paper feeding unit  110  is removed. Since the handle  200  is installed in the vicinity of the approximate center of the case  130   a , a force by which the user pulls the handle  200  is directed towards the center of the developing unit  130  so that the user may remove the developing unit  130  with relatively little effort. 
   As shown in  FIGS. 4 and 5 , in the developing unit  130  that has been removed, the handle  200  pivots on the hinge  201  so as to be folded toward the storage position  230  attached to the case  130   a . When the handle  200  is folded toward the storage position  230 , the package size of the developing unit  130  may be reduced. In this case, the handle  200  encloses an outer surface of the developing unit  130  and relieves a sudden external impact on the developing unit  130 . As a result, the durability of the developing unit  130  may be improved. 
   The developing unit  130  is mounted on the body frame  100  in a reverse order to the above-described removal order. In other words, the user unfolds the handle  200  toward the use position and pushes the gripping unit  220  so as to position the developing unit  130  to the developing unit mounting unit  101 . As described above, when the handle  200  is unfolded toward the use position, the plurality of guide ribs  211  formed on the back surface of the guide plate  210  may guide the transport path of the sheet of paper P fed from the auxiliary paper feeding unit  111 . 
   As described above, in an image forming apparatus provided with a developing unit having a handle in accordance with aspects of the present invention, the handle can be foldably installed on the developing unit. Thus, when the developing unit is packaged, the size of the developing unit may be reduced. Also, an external impact on the developing unit may also be relieved. As a result, the durability of the developing unit may be improved. 
   In addition, the handle may be used to mount and remove the developing unit. Moreover, when the handle is installed on the developing unit, the handle may also be unfolded and used as a paper guide. Accordingly, the utility value of the handle is improved. 
   While the invention has been shown and described with reference to certain embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Technology Category: g