Abstract:
An image forming device includes a first device body, a second device body having a first side end and a second side end opposite to the first side end, the first side end being rotatably joined with the first device body, the second side end turning around the first side end between an opened state and a closed state, a photoconductive body provided in the first device body, an exposure unit provided to the second device body, the exposure unit having an exposure surface exposing the photoconductive body and form a latent image on the photoconductive body, and an exposure unit turning mechanism that turns the exposure unit between an exposure position where the exposure surface is directed to the photoconductive body in the closed state and an evacuation position where the exposure surface is directed to the first side end in the opened state.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority under 35 U.S.C. §119 from Japanese Patent Application No. 2007-250858 filed on Sep. 27, 2007. The entire subject matter of the application is incorporated herein by reference. 
     BACKGROUND 
     1. Technical Field 
     The following description relates to one or more image forming devices such as an electrophotographic copy machine and a printer. 
     2. Related Art 
     In an image forming device such as a copy machine and a printer, a laser scanning method and an LED exposure method have been put into practical use as an image writing method (exposure method). The LED exposure method is a method in which light emitted by a light emitting unit with a plurality of light emitting elements linearly aligned is directed onto a surface of a photoconductive body with an imaging system and a latent image is formed on the surface of the photoconductive body. 
       FIG. 13  schematically shows a configuration of a main portion of a known image forming device when viewed in a direction perpendicular to a carrying direction of a recording medium. The image forming device  101  shown in  FIG. 13  is configured to perform color printing. In a device main body  102 , four drum units  103  are detachably disposed that correspond to yellow (Y), magenta (M), cyan (C), and black (K), respectively, in an order from an upstream side in an arrow A direction as the carrying direction of the recording medium. 
     Each of the drum units  103  is provided with a photoconductive drum  103   a  configured to rotate in an arrow B direction. Further, images of the predetermined colors are sequentially transferred onto the recording medium which is conveyed in the arrow A direction while being stuck to a carrying belt (not shown) by the respective photoconductive drums  103   a  in collaboration with respective transfer rollers  104  rotated concurrently with the photoconductive drums  103   a.    
     Meanwhile, a stacker cover  107  is rotatably supported by the device main body  102  via a rotational shaft  108  extending in a direction perpendicular to the arrow A direction. Further, the stacker cover  107  holds four LED heads  111  disposed in positions corresponding to circumferential surfaces of the photoconductive bodies  103   a  of the drum units  103 , respectively. Thus, the stacker cover  107  is configured to be opened and closed with respect to the device main body  102 , and provided such that the drum units can be replaced when the stacker cover  107  is opened with respect to the device main body  102  (for example, see Japanese Patent Provisional Publication No. 2003-112446). 
     SUMMARY 
     In the above known configuration, the LED heads  111  are fixed substantially perpendicularly to the stacker cover  107 . Therefore, when the stacker cover  107  is opened with respect to the device main body  102 , exposure surfaces of the LED heads  111  are exposed to an open side of the stacker cover  107 . Thereby, the exposure surfaces might be damaged or tainted with dust adhered thereto. 
     Aspects of the present invention is advantageous to provide one or more improved image forming devices that can prevent an exposure surface of an exposure unit thereof from being damaged or contaminated with dust adhered to the exposure surface. 
     According to aspects of the present invention, an image forming device is provided, which includes a first device body having an opening, a second device body having a first side end and a second side end opposite to the first side end, the first side end being rotatably joined with the first device body, the second side end being configured to turn around the first side end between an opened state where the second device body is opened with respect to the first device body and a closed state where the second device body is closed with respect to the first device body so as to cover the opening, a photoconductive body provided in the first device body; an exposure unit provided to the second device body, the exposure unit having an exposure surface configured to expose a surface of the photoconductive body linearly in a predetermined scanning direction and form a latent image on the surface of the photoconductive body, and an exposure unit turning mechanism configured to turn the exposure unit between an exposure position where the exposure surface is directed to the surface of the photoconductive body in the closed state of the second device body and an evacuation position where the exposure surface is directed substantially to the first side end of the second device body in the opened state of the second device body. 
     In some aspects, when the second device body is in the opened state, the exposure surface of the exposure unit is directed to the first side end of the second device body that is rotatably joined with the first device body. Therefore, since the exposure surface of the exposure unit is not exposed to an open side of the second device body in the opened state, it is possible to prevent an exposure surface of an exposure unit from being damaged or contaminated with dust adhered thereto. 
    
    
     
       BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
         FIG. 1  is a cross-sectional side view schematically showing an entire configuration of an LED printer in a state where an upper case is closed in an embodiment according to one or more aspects of the present invention. 
         FIG. 2  is a cross-sectional view schematically showing the entire configuration of the LED printer in a state where the upper case is closed in the embodiment according to one or more aspects of the present invention. 
         FIG. 3  is a perspective view schematically showing an LED unit in the embodiment according to one or more aspects of the present invention. 
         FIG. 4  is a side view schematically showing a state where the LED unit is supported by an LED unit supporting member in the embodiment according to one or more aspects of the present invention. 
         FIG. 5  is an enlarged side view schematically showing a configuration of a lever in the embodiment according to one or more aspects of the present invention. 
         FIG. 6  schematically shows a mechanism for turning the LED unit in the state where the upper case is closed in the embodiment according to one or more aspects of the present invention. 
         FIG. 7  is a perspective view showing a state where arms support the upper case in the embodiment according to one or more aspects of the present invention. 
         FIG. 8  is a perspective view showing a state where a distal end of the arm is supported by a guide member in the embodiment according to one or more aspects of the present invention. 
         FIG. 9  is a perspective view showing a state where the upper case is closed with respect to a mechanical unit in the embodiment according to one or more aspects of the present invention. 
         FIG. 10  is a perspective view showing a state where the upper case is slightly opened with respect to the mechanical unit in the embodiment according to one or more aspects of the present invention. 
         FIG. 11  is a perspective view showing a state where the upper case is completely opened with respect to the mechanical unit in the embodiment according to one or more aspects of the present invention. 
         FIG. 12  schematically shows the mechanism for turning the LED unit in the state where the upper case is opened in the embodiment according to one or more aspects of the present invention. 
         FIG. 13  is a cross-sectional side view schematically showing a known LED printer. 
     
    
    
     DETAILED DESCRIPTION 
     It is noted that various connections are set forth between elements in the following description. It is noted that these connections in general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. 
     Hereinafter, an embodiment according to aspects of the present invention will be described with reference to the accompany drawings.  FIG. 1  is a cross-sectional view schematically showing an entire configuration of an LED printer  5  in an embodiment according to aspects of the present invention. In the LED printer  5  shown in  FIG. 1 , a left side, a right side, a back side, and a front side on the figure are defined as a front side, a rear side, a left side, and a right side, respectively. 
     In  FIG. 1 , an upper case  1  is supported, rotatably with respect to a mechanical unit  3 , by a rotational shaft hole  2  provided at a rear side of the upper case  1  and a rotational shaft  4  provided at a rear side of the mechanical unit  3 . Further, the mechanical unit  3  has an opening  3   a  at an upper side thereof. It is noted that  FIG. 1  shows a state where the upper case  1  is closed with respect to the mechanical unit  3 . 
     In the mechanical unit  3 , four drum units  10 K,  10 Y,  10 M, and  10 C are detachably disposed that respectively correspond to black (K), yellow (Y), magenta (M), and cyan (C) in an order from an upstream side in a direction of an arrow C denoting a carrying direction of a recording paper. 
     The drum units  10 K,  10 Y,  10 M, and  10 C are provided with photoconductive bodies  11 K,  11 Y,  11 M, and  11 C configured to rotate in an arrow D direction, respectively. Images of the predetermined colors are sequentially transferred onto the recording paper, which is conveyed in an arrow C direction while being stuck to a carrying belt  14 , by the photoconductive bodies  11 K,  11 Y,  11 M, and  11 C in collaboration with transfer rollers  12 K,  12 Y,  12 M, and  12 C rotated concurrently with the photoconductive bodies  11 K,  11 Y,  11 M, and  11 C. Thereafter, the images of the predetermined colors on the recording paper are thermally fixed with a fixing unit  16 . Then, the recording paper is discharged by carrying rollers  18  to a catch tray  19  provided to the upper case  1 . 
     Meanwhile, the upper case  1  includes four LED units  20 K,  20 Y,  20 M, and  20 C provided in positions that correspond to circumferential surfaces of the photoconductive bodies  11 K,  11 Y,  11 M, and  11 C of the drum units  10 K,  10 Y,  10 M, and  10 C, respectively. 
     LED heads  32 K,  32 Y,  32 M, and  32 C (described later) provided at distal ends of the LED units  20 K,  20 Y,  20 M, and  20 C are disposed close to the photoconductive bodies  11 K,  11 Y,  11 M, and  11 C, respectively, and thereby it is possible to expose the circumferential surfaces of the photoconductive bodies  11 K,  11 Y,  11 M, and  11 C. The photoconductive bodies  11 K,  11 Y,  11 M, and  11 C are rotated in the arrow D direction and exposed linearly along a right-to-left direction (main scanning direction) thereof. 
     It is noted that the drum units  10 , photoconductive bodies  11 , transfer rollers  12 , LED units  20 , and LED heads  32  in general and, unless specified otherwise, are configured in the same manner, respectively. If it is required to distinguish each element of the same sort of component from the other elements, each element will be distinguished with a reference character (K), (Y), (M), or (C) representing a corresponding color attached thereto. 
       FIG. 2  schematically shows a state where the upper case  1  is opened with respect to the mechanical unit  3 . When the upper case  1  is opened, the LED unit  20  is turned in conjunction with the upper case  1  so that each of the drum units  10  can be replaced. Hereinafter, referring to  FIGS. 3 to 12 , a configuration of the LED unit  20  and a mechanism for turning the LED unit  20  in conjunction with the upper case  1  will be described. 
       FIG. 3  is a perspective view schematically showing the LED unit  20 . The LED head  32  provided at a lower portion of the LED unit  20  is configured with an LED array (not shown) of LEDs aligned linearly along the main scanning direction and a Selfoc Lens Array (SLA) (not shown) being integrated. The LED head  32  has an exposure surface  32   a  facing in an illuminating direction of the LED head  32 . The LED head  32  is held by holding members  37   a  and  37   b  that extend downward from an LED supporting body  35  elongated in the right-to-left direction. 
     Additionally, the LED supporting body  35  includes bosses  36   a  and  36   b  each of which protrudes outward along the right-to-left direction. Further, an arm portion  34  extending obliquely upward is provided at a right side end of the LED supporting body  35 . A projection  38  that protrudes outward in the same manner as the boss  36   a  is provided in the vicinity of a distal end of the arm portion  34 . 
       FIG. 4  is a side view schematically showing a state where the LED unit  20  is supported by an LED unit supporting member  50 .  FIG. 5  is an enlarged view of a lever  80  shown in  FIG. 4 .  FIG. 6  schematically shows a plate  60  for linking and turning the four LED units  20 .  FIG. 7  is a perspective view showing a state where the LED unit supporting member  50  is attached to the upper case  1 . It is noted that  FIG. 7  shows a state where the upper case  1  is opened with respect to the mechanical unit  3  and the mechanical unit  3  is omitted. 
     As illustrated in  FIG. 4 , the LED units  20 K,  20 Y,  20 M, and  20 C are supported by the LED unit supporting member  50  and aligned in a front-to-rear direction. Specifically, the boss  36   a  of the LED unit  20  is fitted into a hole  50   a  of the LED unit supporting member  50 . The LED unit  20  is supported rotatably with respect to the LED unit supporting member  50 . It is noted that another LED unit supporting member  50  is provided at a left side of the upper case  1  as well, and the boss  36   b  is fitted into a hole  50   b  of the LED unit supporting member  50  provided at the left side of the upper case  1  (see  FIG. 7 ). 
     As illustrated in  FIGS. 4 and 5 , the LED unit supporting member  50  is provided with a curved opening  50   c  penetrating the LED unit supporting member  50  in a circular arc shape and a rotational center boss  88  protruding rightward (toward a front side on the figures). It is noted that the LED unit supporting member  50  provided at the left side of the upper case  1  is not provided with the lever  80 , curved opening  50   c , or rotational center boss  88 . 
     The lever  80  includes a hole  80   c  into which the rotational center boss  88  is fitted, a boss  80   d  located under the hole  80   c , a rectangle link portion  80   a  extending upward from the hole  80   c  so as to be oblique to a rear side, and a long hole  80   b  formed around a shape of the link portion  80   a . Further, the lever  80  is configured to turn around the rotational center boss  88 . 
       FIG. 6  indicates the LED unit supporting member  50  shown in  FIG. 4  with a chain double-dashed line, and illustrates the plate  60  for linking and turning the four LED units  20 . It is noted that  FIG. 6  shows the LED unit supporting member  50  at the right side, and the LED unit supporting member  50  at the left side is not provided with the plate  60 . 
     The plate  60  is provided at the left side (back side on  FIG. 6 ) of the LED unit supporting member  50 , and has an elongated shape extending in the front-to-rear direction. To a rear end of the plate  60 , a spring member  65  is attached as a tension coil spring. A locking portion  65   a  provided at a front end of the spring member  65  is hooked to a rear end of the plate  60 , and a locking portion  65   b  provided at a rear end of the spring member  65  is hooked to a part of the LED unit supporting member  50 . 
     Further, the plate  60  is provided with recess portions  60   a ,  60   b ,  60   c , and  60   d , into which the respective projections  38  of the four LED units  20 K,  20 Y,  20 M, and  20 C are loosely fitted. Additionally, the plate  60  is provided with a protrusion  63 , which protrudes rightward (toward the front side on  FIG. 6 ) from the curved opening  50   c  of the LED unit supporting member  50 . Further, the protrusion  63  is fitted into the long hole  80   b  of the lever  80  ( FIG. 4 ). 
     As illustrated in  FIG. 7 , between the upper case  1  and the mechanical unit  3 , a pair of arms  40   a  and  40   b  is provided. In addition, between the arms  40   a  and  40   b  and the mechanical unit  3 , tension coil springs  42   a  and  42   b  are provided from a vicinity of centers of the arms  40   a  and  40   b  toward the rear side, respectively. 
     Cylindrical members  41   a  and  41   b  respectively provided at lower portions of the arms  40   a  and  40   b  are turnably fitted around a shaft (not shown) of the mechanical unit  3 . In addition, a distal end of the arm  40   a  is configured to slide along an arrow E direction with respect to a guide member  72  attached to the upper case  1 . Further, another guide member  72  is provided at the left side of the upper case  1 , and a distal end of the arm  40   b  is as well configured to slide with the left guide member  72 . 
     It is noted that the upper case  1  maintains the state opened with respect to the mechanical unit  3  in  FIG. 7 . In this case, the arms  40   a  and  40   b  support the upper case  1 , and the arms  40   a  and  40   b  are biased backward (i.e., toward the rear side) by the tension coil spring  42   a  and  42   b . Thereby, the upper case  1  maintains the opened state while the distal ends of the arms  40   a  and  40   b  are left in a stationary state. 
       FIG. 8  is a perspective view showing the arm  40   a  and guide member  72  shown in  FIG. 7 . Further,  FIG. 8  shows a moving member  45  moving in conjunction with the arm  40   a . At the distal end of the arm  40   a , a cylindrical protruded portion  44   a  is provided to protrude leftward, while a cylindrical protruded portion  44   b  (indicated by a dashed line) is provided on the right side of the cylindrical protruded portion  44   a  via the arm  40   a . The protruded portion  44   b  is supported by a guide plate  73  of the guide member  72 , and configured to move along the guide plate  73  in the front-to-rear direction (i.e., along the arrow E direction). 
     In addition, the protruded portion  44   a  is fitted into a rectangular hole  45   a  of the moving member  45 . The moving member  45  is provided to slide along the arrow E direction with respect to the upper case  1 , and configured to move in conjunction with sliding along the arrow E direction of the distal end of the arm  40   a . Further, the moving member  45  includes a pressing portion  45   c  provided at a rear end thereof, and a tilted portion  45   d  extending toward an upper front side from the pressing portion  45   c . Meanwhile, a distal end of the arm  40   b  is configured to slide with respect to the left guide member  72  in the same manner as the arm  40   a , yet not provided with the moving member  45 . 
     Next, referring to  FIGS. 9 to 11 , how the upper case  1  is opened and closed with respect to the mechanical unit  3  and how the LED unit  20  is turned in conjunction with the opening and closing of the upper case  1  will be described in detail. It is noted that,  FIGS. 9 to 11 , the arm  40   a  is denoted by a chain double-dashed line in a clearly understandable manner, and the tension coil springs  42   a  and  42   b  are not shown.  FIG. 9  shows a state where the upper case  1  is closed with respect to the mechanical unit  3 . In  FIG. 10 , the upper case  1  is slightly opened, and in  FIG. 11 , the upper case  1  is completely opened. 
     When the upper case  1  is closed with respect to the mechanical unit  3  as shown in  FIG. 9 , the LED unit  20  is disposed substantially perpendicular to the upper case  1  so as to expose the photoconductive body  11 . 
     Further, the arms  40   a  and  40   b  are disposed substantially parallel to the upper case  1 . In this case, the protruded portion  44   b  of each of the arm  40   a  and  40   b  is disposed in the vicinity of a front end of the guide plate  73 . Further, the upper case  1  is provided with a damper  70  configured with a compression coil spring. The damper  70  is pressed by a side face  45   b  of the moving member  45  moving in conjunction with the arm  40   a . Namely, the upper case  1  is stationary while the damper  70  is compressed. 
     It is noted that another damper  70  is provided at the left side of the upper case  1 , and more specifically, provided at a front end  72   a  of the left guide member  72 . When the upper case  1  is set to the closed state from the opened state, the side face  45   b  of the moving member  45  at the right side and the distal end of the arm  40   b  at the left side come into contact with the dampers  70 , respectively. Therefore, it can be avoided that the upper case  1  is closed with great force. 
     When the upper case  1  is slightly opened as shown in  FIG. 10 , the upper case  1  is turned around the rotational shaft  4 , and in conjunction with it, the distal ends of the arms  40   a  and  40   b  slide backward (in an arrow F direction) along the guide member  72 . It is noted that the protruded portion  44   a  fitted into the rectangle hole  45   a  of the moving member  45  is provided at the distal end of the arm  40   a , and thus the moving member  45  slides backward (i.e., toward the rear side) in conjunction with the movement of the distal end of the arm  40   a . 
     When the moving member  45  slides backward, the pressing portion  45   c  at the rear end of the moving member  45  comes into contact with the boss  80   d  of the lever  80 . When the upper case  1  is further opened from the above state, the moving member  45  slides further backward (see  FIG. 11 ). At this time, when the moving member  45  slides backward, the boss  80   d  is pressed by the pressing portion  45   c  of the moving member  45  and thereafter pressed by the tilted portion  45   d . This movement causes the boss  80   d  to turn in an arrow G direction. When the boss  80   d  is turned in the arrow G direction shown in  FIG. 5 , the link portion  80   a  is turned in an arrow H direction. 
     When the link portion  80   a  is turned in the arrow H direction, the protrusion  63  is concurrently turned. When the protrusion  63  is turned in the arrow H direction, as illustrated in  FIG. 12 , the plate  60  is moved forward (i.e., toward the front side) around the bosses  36   a  against an elastic force of the spring member  65 . Further, at this time, the LED units  20 K,  20 Y,  20 M, and  20 C are turned backward around the respective bosses  36   a . When the LED unit  20  is turned, the exposure surface  32   a  is directed toward a rotational center of the upper case  1 . It is noted that, when the boss  80   d  is pressed by the pressing portion  45   c , the boss  80   d  is turned in the arrow G direction while receiving a resistance force from the tilted portion  45   d . Thereby, it can be avoided that the LED unit  20  is rapidly turned. 
     In addition, a turned angle of the LED unit  20 C is smaller than those of the LED units  20 K,  20 Y, and  20 M. This is because the recessed portion  60   d  for the LED unit  20 C into which the projection  38  of the LED unit  20 C is fitted is not circular but substantially oval oblique backward. When the plate  60  moves forward, the LED units  20 K,  20 Y, and  20 M are turned around the respective bosses  36   a . Meanwhile, the LED unit  20 C is turned around the boss  36   a , yet at this time, the projection  38  moves relatively toward an upper rear side along the substantially oval recessed portion  60   d . Thereby, the tilt angle of the LED unit  20 C with respect to the upper case  1  is larger than those of the LED units  20 K,  20 Y, and  20 M. 
     Further, the catch tray  19  provided at the upper portion of the LED unit  20  is formed to extend in a rear-to-front direction in a manner curved upward (see  FIGS. 1 and 2 ). Since the four LED units  20  are attached along the form of the catch tray  19 , the LED unit  20 C at the rearmost side is provided with the greatest tilt angle with respect to the upper case  1 . It is noted that the tilt angles of the LED units  20  to the upper case  1  in the present embodiment have a relationship of  20 C&gt; 20 K= 20 Y= 20 M. 
     Further, while the upper case  1  is turned from the state shown in  FIG. 9  to the state shown in  FIG. 10 , the LED units  20  maintain the state substantially perpendicular to the upper case  1 . During this period, the LED units  20  are on the way to being got out of the mechanical unit  3  in conjunction with the upper case  1 . At this time, the LED units are disposed in the vicinity of the respective drum units  10 , and therefore the LED units  20  are required to be got out of the mechanical unit  3  so as not to contact the drum units  10 .  FIG. 10  shows a state where the LED units  20  are completely got out of the mechanical unit  3 . When the upper case  1  is further opened from this state, the LED units  20  are turned. 
     Thus, when the upper case  1  is opened, the exposure surfaces  32   a  of the LED units  20  are directed toward the rotational center of the upper case  1 . Therefore, the exposure surfaces  32   a  are not exposed to an open side of the upper case  1 . Hence, the exposure surfaces  32   a  are hardly touched by a user, and thus can be prevented from being damaged or tainted with dust adhered thereto. 
     Further, since all the LED units  20  are turned when the upper case  1  is opened, the drum units  10  can easily be replaced without having to widely open the upper case  1 . Thereby, since the upper case  1  does not have to be widely opened with respect to the mechanical unit  3 , the LED printer  5  can be prevented from being fallen down. 
     Hereinabove, the embodiments according to aspects of the present invention have been described. The present invention can be practiced by employing conventional materials, methodology and equipment. Accordingly, the details of such materials, equipment and methodology are not set forth herein in detail. In the previous descriptions, numerous specific details are set forth, such as specific materials, structures, chemicals, processes, etc., in order to provide a thorough understanding of the present invention. However, it should be recognized that the present invention can be practiced without reapportioning to the details specifically set forth. In other instances, well known processing structures have not been described in detail, in order not to unnecessarily obscure the present invention. Only exemplary embodiments of the present invention and but a few examples of its versatility are shown and described in the present disclosure. It is to be understood that the present invention is capable of use in various other combinations and environments and is capable of changes or modifications within the scope of the inventive concept as expressed herein.