Patent Publication Number: US-7212766-B2

Title: Wet-type electrophotographic image forming apparatus and a setting method thereof

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit under 35 U.S.C. §119(a) of Korean Patent Application No. 2004-28611 entitled “A Wet-Type Electrophotographic Image Forming Apparatus And A Setting Method Thereof”, filed in the Korean Intellectual Property Office on Apr. 26, 2004, the entire contents of which are incorporated herein by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a wet-type electrophotographic image forming apparatus. More particularly, the present invention relates to a wet-type electrophotographic image forming apparatus having a fitting unit and an ink recover unit for discarding waste ink or recycling ink, and a setting method thereof. 
   2. Description of the Related Art 
   A wet-type electrophotographic image forming apparatus is a printing device that forms an electrostatic latent image by scanning a photoconductive medium with laser beams, fuses a developer onto the electrostatic latent image to obtain a visible image, transfers the visible image to paper, and outputs a desired image. Compared to a dry-type electrophotographic image forming apparatus, the wet-type apparatus is advantageous in that it can obtain a much more vivid image. Therefore, it is more suitable for providing a color printing of high quality. 
   Furthermore, in the wet type electrophotographic image forming apparatus, ink is circulated from a developing unit to an ink cartridge unit for the purpose of reuse. The recycling procedure is performed by passing ink through a developing unit, an ink recover unit, a fitting unit, and into an ink cartridge unit. 
     FIG. 1  is a schematic view showing a conventional wet-type electrophotographic image forming apparatus. Referring to  FIG. 1 , a wet-type electrophotographic image forming apparatus  100  comprises a body  101 , a developing unit  102  disposed in the body  101 , an ink cartridge unit  106  disposed in the body  101  for supplying ink to the developing unit  102 , a door unit  103  disposed in the body  101 , and a fitting unit  104  disposed in the body  101 . The door unit  103  is provided with a mounting supporter  103   a  for pushing the developing unit  102  in one direction to completely mount the developing unit  102 . 
   The developing unit  102  includes an ink discharge channel cover  102   a  for discharging the ink, and the fitting unit  104  includes a male fitting portion  104   a  fitted into a female fitting portion  106   a  formed in the ink cartridge unit  106 . 
   According to the above construction example, in order to completely mount the developing unit  102 , a user has to perform a series of tasks to open the ink discharge channel cover  102   a , fit the male fitting portion  104   a  into the female fitting portion  106   a , and then close the door unit  103  in the ‘S’ direction. These individual tasks can become tedious and can result in the deterioration of the developing unit  102  and the fitting unit  104  over time. 
   Accordingly, a need exists for a image forming apparatus having a system and method to engage an ink discharge channel and function using a minimum number of individual steps, and preferably, using a motion generated by a single step, such as opening and closing a door unit. 
   SUMMARY OF THE INVENTION 
   The present invention has been developed in order to solve the above and other problems in the related art. Accordingly, an object of the present invention is to provide a wet-type electrophotographic image forming apparatus having an improved construction which is capable of facilitating a setting procedure, and a setting method thereof. 
   The above object is achieved by providing a wet-type electrophotographic image forming apparatus comprising a body, a developing unit disposed in the body, an ink cartridge unit disposed in the body for supplying ink to the developing unit, a door unit disposed in the body, an ink recovery unit disposed in the body for discarding waste ink and circulating ink, and a fitting unit connecting the developing unit and the ink cartridge unit. The door unit moves in relation to the movement of at least one of the ink recovery unit and the fitting unit. 
   The image forming apparatus further provides the fitting unit to be engaged and disengaged with the ink cartridge unit according to the closing and opening movements of the door unit. 
   A rotary shaft is disposed in the developing unit of the image forming apparatus, and the door unit includes a mounting support for completely mounting the developing unit, and includes a recess for supporting and guiding the rotary shaft of the developing unit. 
   The ink cartridge unit of the image forming apparatus includes a female fitting portion formed therein, and the fitting unit includes a male fitting portion and a fitting unit driver. The fitting unit driver is operated according to the closing and opening movements of the door unit to engage and disengage the male fitting portion with the female fitting portion. 
   The fitting unit driver of the image forming apparatus comprises a rotary member disposed at the door unit, and a vertical member connected to the male fitting portion. The rotary member and the vertical member contact each other, and the vertical member transforms a rotational motion of the rotary member into a linear motion. 
   The ink recover unit is operated according to the closing and opening movements of the door unit. The developing unit includes an ink discharge channel cover for discharging or circulating ink, and the ink recover unit includes an ink recover unit driver for opening and closing the ink discharge channel cover according to the closing and opening movements of the door unit. The ink recover unit further includes an ink receptacle for collecting the discharged ink. 
   An operating lever is disposed at the door unit to operate the ink recover unit driver, wherein the ink recover unit driver comprises an opening and closing member to open and close the ink discharge channel cover, an opening and closing shaft engaged with the opening and closing member, and a clutch mounted on the opening and closing shaft. The clutch is operated via a contact with the operating lever. 
   The above objects are further achieved in another embodiment of the present invention by providing a wet-type electrophotographic image forming apparatus comprising a body, a developing unit disposed in the body, an ink cartridge unit disposed in the body for supplying ink to the developing unit, a door unit disposed in the body, an ink recover unit disposed in the body for discharging waste ink and circulating ink, and a fitting unit connecting the developing unit and the ink cartridge unit. The door unit moves in relation to the movement of at least one of the fitting unit and the ink recover unit. 
   The above objects are further achieved in yet another embodiment of the present invention by providing a wet-type electrophotographic image forming apparatus comprising a body, a developing unit disposed in the body, an ink cartridge unit disposed in the body for supplying an ink to the developing unit, a door unit disposed in the body, and an ink recover unit disposed in the body for discharging waste ink and circulating ink. The door unit moves in relation to the movement of the ink recovery unit. 
   The above objects are achieved by providing a setting method of a wet-type electrophotographic image forming apparatus in accordance with an embodiment of the present invention, the method comprising the steps of opening and closing a door unit and moving a fitting unit in relation to the movement of the door unit, the fitting unit being engaged and disengaged with an ink cartridge unit through such movement. 
   The step of moving the fitting unit further comprises the steps of rotating a rotary member disposed at the door unit, linearly moving a vertical member in engagement with the rotary member, and linearly moving a male fitting portion disposed at the vertical member. 
   The setting method further comprises the step of detecting the opening and closing of the door unit using a sensor disposed at one side of the door unit. If necessary, the setting method further comprises the steps of determining whether the door unit is opened or closed, and displaying an error message when the door unit is opened. 
   The setting method further comprises the steps of moving the ink recover unit in relation to the movement of the door unit, and discharging the ink from the developing unit. 
   The step of moving the ink recover unit comprises the steps of rotating an operating lever disposed at the door unit, rotating a clutch in contact with the operating lever, rotating an opening and closing shaft on which the clutch is disposed, rotating an opening and closing member disposed around the opening and closing shaft, and opening and closing an ink discharge channel cover disposed at the developing unit. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above objects and other advantages of the present invention will be more apparent by describing embodiments of the present invention with reference to the drawing figures, in which: 
       FIG. 1  is a schematic view showing a conventional wet-type electrophotographic image forming apparatus; 
       FIG. 2  is a schematic view showing a wet-type electrophotographic image forming apparatus according to an embodiment of the present invention; 
       FIG. 3  is a view showing the fitting unit of  FIG. 2 ; 
       FIG. 4A  is a view showing the ink recover unit of  FIG. 2 ; 
       FIG. 4B  is a view from the direction A of  FIG. 4A ; 
       FIG. 4C  is a view showing the ink discharge channel cover of  FIG. 4B ; 
       FIG. 5A  is a view showing the door unit of  FIG. 2 ; 
       FIG. 5B  is a view from the direction B of  FIG. 5A ; 
       FIG. 6  is a flowchart showing the operation of the fitting unit of  FIG. 3  according to an embodiment of the present invention; and 
       FIG. 7  is a flowchart showing the operation of the ink recover unit of  FIG. 4A  according to another embodiment of the present invention. 
   

   In the figures, it will be understood that like reference numerals refer to like features and structures. 
   DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
   Hereinafter, embodiments of the present invention will be described in greater detail with reference to the accompanying figures. 
   In embodiments of the present invention described below, a wet-type electrophotographic image forming apparatus is exemplified, in which, an ink cartridge unit and a fitting unit move in relation to the movement of a door unit. 
     FIG. 2  is a schematic view showing a wet-type electrophotographic image forming apparatus according to an embodiment of the present invention. Referring to  FIG. 2 , a wet-type electrophotographic image forming apparatus  1  comprises a body  10 , a developing unit  20 , an ink cartridge unit  60 , an ink recover unit  50 , a fitting unit  40 , and a door unit  30 . 
   The developing unit  20  is disposed in an upper part of the body  10  for supplying a developing solution to a photoconductive drum (not shown). 
   The ink cartridge unit  60  is disposed in a lower part of the body  10  for supplying ink X to the developing unit  20 . 
   The ink recover unit  50  is disposed between an ink discharge channel  21  of the developing unit  20  and the fitting unit  40 , and can be securely fixed to the body  10  for collecting the ink X from the developing unit  20 . 
   The fitting unit  40  connects the ink recover unit  50  and the ink cartridge unit  60 . 
   The door unit  30  is hinged on one side of the body  10  for completely mounting the developing unit  20  and also operating the ink recover unit  50  and the fitting unit  40 . 
   Between the ink discharge channel  21  of the developing unit  20  and the ink recover unit  50 , the ink X is discharged in a natural manner via gravity without requiring a connecting tube therebetween. A flexible hose  70  is connected between the ink recover unit  50  and the fitting unit  40  to then direct the ink X in an inductive discharging manner. 
   A connecting hose  80  is also connected between the ink cartridge unit  60  and the developing unit  20  for allowing the ink X to be circulated from the ink cartridge unit  60  to the developing unit  20  in the arrowed direction “Q”. 
   In the above construction example, the ink X is circulated through the developing unit  20 , the ink recover unit  50 , the fitting unit  40 , and the ink cartridge unit  60  in accordance with an embodiment of the present invention. 
     FIG. 3  is a view showing the fitting unit  40  of  FIG. 2  in greater detail. Referring to  FIG. 3 , the fitting unit  40  comprises a male fitting portion  41  to be engaged with the ink cartridge unit  60 , and a fitting unit driver for engaging and disengaging the male fitting portion  41  with a female fitting portion  61  formed in the ink cartridge unit  60  according to the opening and closing movements of the door unit  30 . 
   The fitting unit driver comprises a rotary member  31  disposed at the door unit  30 , and a vertical member  42  engaged with the rotary member  31  to move in relation to the movement of the rotary member  31 . 
   The male fitting portion  41  is connected with one side of the vertical member  42 , which comprises a rack, and is secured to the rack using any suitable fastener, such as a screw. 
   The rotary member  31  is disposed at an end of the door unit  30  and is generally a gear that rotates in engagement with the vertical member  42 . 
   It is preferred that the rotary member  31  and the vertical member  42  respectively comprise the gear and rack to transform a rotary motion into a linear motion. 
   A hose  70  connects a collecting receptacle  53  and the male fitting portion  41 , and is expandable and contractible to maintain the connection therebetween when the male fitting portion  41  linearly moves in the arrowed direction “I”. 
   In the above construction example, when the door unit  30  turns in the arrowed direction “S”, the rotary member  31  disposed at the door unit  30  rotates in the arrowed direction “F” and thus the vertical member  42  engaged with the rotary member  31  linearly moves in the arrowed direction “H”. At this time, the male fitting portion  41  connected with one side of the vertical member  42  linearly moves in the arrowed direction “I” and is fitted into, or engaged with, the female fitting portion  61 . 
     FIG. 4A  illustrates the ink recover unit  50  of  FIG. 2 ,  FIG. 4B  is a view from the direction A of  FIG. 4A , and  FIG. 4C  is a view to illustrate the operation of an ink discharge channel cover  51  of  FIG. 4B . Referring to  FIGS. 4A ,  4 B, and  4 C, the ink recover unit  50  comprises an ink recover unit driver  52  for opening and closing the ink discharge channel cover  51  according to the opening and closing of the door unit  30 , and the collecting receptacle  53  for collecting the discharged ink X. 
   As shown in  FIG. 4A , the ink recover unit driver  52  comprises an opening/closing member  52   a  for opening and closing the ink discharge channel cover  51 , an opening/closing shaft  52   b  around which the opening/closing member  52   a  is engaged, and a clutch  52   c  engaged with the opening/closing shaft  52   b.    
   Referring to  FIGS. 4B and 4C , the ink discharge channel cover  51  includes protrusions  51   a  formed at opposite sides thereof, and is connected to an ink discharge channel  21  disposed at a lower part of the developing unit  20  by a hinge  51   c  on which the ink discharge channel cover  51  swings in the arrowed directions “0” and “P”. 
   The opening/closing shaft  52   b  is rotatably connected with one side of the body  10  (see  FIG. 2 ). 
   The opening/closing member  52   a  for opening and closing the ink discharge channel cover  51  is concave to push the protrusions  51   a  formed at the opposite sides of the ink discharge channel cover  51  in the arrowed direction “N”. The opening/closing shaft  52   b  is inserted through the opening/closing member  52   a.    
   The clutch  52   c  is inserted onto an end of the opening/closing shaft  52   b , and is ‘L’ shaped to contact an operating lever  32  disposed at an end of the door unit  30 . 
   The collecting receptacle  53  is secured to one side of the body  10  (see  FIG. 2 ) for collecting the ink X falling from the ink discharge channel  21 , and can be a funnel to prevent the ink from spattering. 
   Referring back to  FIG. 4A , when the door unit  30  turns in the arrowed direction “S”, the operating lever  32  disposed at the end of the door unit  30  moves in the arrowed direction “K” to thereby push the clutch  52   c  in the arrowed direction “L”. At this time, the clutch  52   c  rotates the opening/closing shaft  52   b  in the arrowed direction “M”. 
   Referring to  FIGS. 4B and 4C , when the opening/closing shaft  52   b  rotates, the opening/closing member  52   a  engaged around the opening/closing shaft  52   b , rotates in the arrowed direction “N”. At this time, the opening/closing member  52   a  pushes the protrusions  51   a  formed at the opposite sides of the ink discharge channel cover  51  to thereby open the ink discharge channel cover  51  in the arrowed direction “O”. Accordingly, the ink X is discharged by gravity from the ink discharge channel  21 . 
   In the reverse order of the above process, when the door unit  30  turns in the arrowed direction “R”, the opening/closing member  52   a  does not push the protrusions  51   a , and the ink discharge channel cover  51  is closed in the arrowed direction “P” by a recovering force of a spring  51   b  connected between the ink discharge channel cover  51  and the ink discharge channel  21 . Accordingly, the discharge of the ink X is stopped. 
     FIG. 5A  is a view showing the door unit of  FIG. 2  in detail, and  FIG. 5B  is a view from the direction “B” of  FIG. 5A . Referring to  FIGS. 5A and 5B , the door unit  30  comprises a mounting supporter  30   a  for pushing the developing unit  20  in the arrowed direction “W” to completely mount the developing unit  20 , and a recess  31   a  supporting and guiding a rotary shaft  22  of the developing unit  20 . 
   A bearing  31   b  is inserted into the recess  31   a  to rotate the rotary shaft  22  of the developing unit  30 . An end of the rotary shaft  22  has a chamfered end  22   a  to facilitate the insertion of the rotary shaft  22  into the bearing  31   b.    
   When the door unit  30  turns in the arrowed direction “S”, the mounting supporter  30   a  of the door unit  30  pushes the developing unit  20  in the arrowed direction “W” to thereby completely mount the developing unit  20 . 
   The chamfered end  22   a  of the rotary shaft  22  of the developing unit  20  is inserted into the bearing  31   b  fitted into the recess  31   a  of the door unit  30 . The rotary shaft  22  is thereby supported and rotated in the bearing  32   b.    
     FIG. 6  is a flowchart illustrating the operation of the fitting unit  40  of  FIG. 3  according to an embodiment of the present invention. Referring to  FIG. 6 , a method of operating the fitting unit  40  comprises the steps of opening and closing the door unit  30  at step S 20 , thereby turning the rotary member  31  disposed at the door unit  30  at step S 21 , and linearly moving the vertical member  42  engaged with the rotary member  31  at step S 22 . The linear movement of the vertical member  42  results in linearly moving the male fitting portion  41  connected with the vertical member  42  at step S 23 , thereby engaging and disengaging the male fitting portion  41  of the fitting unit  40  with the female fitting portion  61  formed in the ink cartridge unit  60  at step S 24 . The operating method further provides sensing the opening and closing of the door unit  30  using a sensor disposed at one side of the door unit at step S 25 , determining whether the door unit  30  is normally opened and closed at step S 26 , and displaying an error message if the door unit  30  is not normally opened and closed at step S 27 . 
     FIG. 7  is a flowchart showing the operation of the ink recover unit  50  of  FIG. 4A  according to another embodiment of the present invention. Referring to  FIG. 7 , an operating method of the ink recover unit  50  comprises the steps of opening and closing the door unit  30  at step S 10 , thereby turning the operating lever  32  disposed at the end of the door unit  30  at step S 11  and rotating the clutch  52   c  in contact with the operating lever  32  at step S 12 . The rotating of the clutch  52   c  is provided for rotating the opening/closing shaft  52   b  on which the clutch  52   c  is disposed at step S 13 , thereby rotating the opening/closing member  52   a  disposed around the opening/closing shaft  52   b  at step S 14 . The rotating of the opening/closing member  52   a  is provided for closing and opening the ink discharge channel cover  51  disposed at the developing unit  20  at step S 15 , and thereby blocking discharge and allowing discharge of the ink, respectively, at step S 16 . The operating method further provides sensing the opening and closing of the door unit  30  using a sensor disposed at one side of the door unit at step S 17 , determining whether the door unit  30  is normally opened and closed at step S 18 , and displaying an error message if the door unit  30  is not normally opened and closed at step S 19 . 
   According to embodiments of the image forming apparatus as constructed above, a user can easily and precisely set the fitting unit  40  and the ink recover unit  50  using the door unit  30 . Also, the door unit  30  completely mounts the developing unit  20  and supports and guides the rotary shaft of the developing unit  20 , thereby facilitating a color-registration stabilized wet-type electrophotographic image forming apparatus. 
   Although a number of exemplary embodiments of the present invention have been described, it will be understood by those skilled in the art that the present invention should not be limited to the described embodiments, but various changes and modifications can be made within the spirit and scope of the present invention as defined by the appended claims.