Patent Publication Number: US-2023152730-A1

Title: Structure for driving toner inlet shutter of developing cartridge by using motor

Description:
BACKGROUND 
     An image forming apparatus using an electrophotographic method forms a visible toner image on a photoconductor by supplying toner to an electrostatic latent image formed on the photoconductor, transfers the toner image to a print medium via an intermediate transfer medium or directly, and fixes the transferred toner image on the print medium. 
     A developing cartridge contains toner to form the visible toner image by supplying toner to the electrostatic latent image formed on the photoconductor. When toner contained in the developing cartridge is consumed, the developing cartridge may be removed from the image forming apparatus, and a new developing cartridge may be mounted in the image forming apparatus. As an alternative, a toner refill kit, such as a toner refill cartridge, may be mounted on a toner refilling portion to refill the developing cartridge with new toner. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic perspective view of an electrophotographic image forming apparatus according to an example. 
         FIG.  2    is a schematic configuration diagram of the electrophotographic image forming apparatus shown in  FIG.  1    according to an example. 
         FIG.  3    is an exploded perspective view of a toner refilling portion according to an example. 
         FIG.  4    is a plan view showing a state in which a toner inlet shutter is at an inlet location according to an example. 
         FIG.  5    is a plan view showing a state in which a toner inlet shutter is at a blocking location according to an example. 
         FIG.  6    is a block diagram showing a driving structure for rotating a toner inlet shutter by using a driving motor according to an example. 
         FIG.  7    is an exploded perspective view of a one-way clutch according to an example. 
         FIGS.  8  and  9    are schematic views showing an operation of the one-way clutch shown in  FIG.  7    according to various examples. 
         FIG.  10    is a schematic configuration diagram of a one-way clutch according to an example. 
         FIG.  11    is a schematic partial exploded perspective view of a toner refill cartridge according to an example. 
     
    
    
     DETAILED DESCRIPTION 
     An electrophotographic image forming apparatus includes a developing cartridge in which toner is contained. The developing cartridge is to supply toner to an electrostatic latent image formed on a photoconductor to develop the electrostatic latent image into a visible toner image. When toner contained in the developing cartridge is consumed, a toner refill cartridge may be used to refill the developing cartridge with new toner. A toner inlet shutter provided in the developing cartridge may be rotated to open a toner inlet by mounting the toner refill cartridge on the developing cartridge and rotating the toner refill cartridge. However, when a user excessively rotates the toner refill cartridge, the toner inlet shutter may break. When the user does not fully rotate the toner refill cartridge, the toner inlet may not be completely opened, and thus, toner may leak in a toner refilling process. 
     In an example, a driving motor may be used to drive a toner inlet shutter for opening and closing a toner inlet. A driving force of the driving motor may be selectively transmitted to the toner inlet shutter by a clutch. The clutch may selectively transmit the driving force to the toner inlet shutter according to a rotation direction of the driving motor. A location of the toner inlet shutter may be detected by a location detecting sensor, and thus, may be reliably switched between a location for opening the toner inlet and a location for closing the toner inlet. A toner outlet shutter for opening and closing a toner outlet of the toner refill cartridge may be connected to the toner inlet shutter and driven by the driving motor. Hereinafter, examples of an image forming apparatus will be described with reference to the accompanying drawings. 
       FIG.  1    is a schematic perspective view of an electrophotographic image forming apparatus according to an example. 
     Referring to  FIG.  1   , an electrophotographic image forming apparatus may include a main body  1 , a driving motor  100 , a developing cartridge  2  for forming a visible toner image by supplying toner contained in a toner container  230  to an electrostatic latent image formed on a photoconductor, and a clutch  110 . The developing cartridge  2  may include the toner container  230  in which toner may be contained, a mounting portion  11  to receive a toner refill cartridge  9 , a toner inlet portion  12  for connecting the mounting portion  11  to the toner container  230 , and a toner inlet shutter  13  which may be switched between a blocking location, for blocking the toner inlet portion  12 , and an inlet location, for opening the toner inlet portion  12 . The clutch  110  is to selectively transmit a driving force of the driving motor  100  to the toner inlet shutter  13 . 
       FIG.  2    is a schematic configuration diagram of the electrophotographic image forming apparatus shown in  FIG.  1    according to an example. 
     Referring to  FIG.  2   , an image forming process will be briefly described. A charging bias voltage may be applied to a charging roller  23 , and the charging roller  23  may charge a photosensitive drum  21  with a uniform electric potential. An optical scanner  4  is to scan the photosensitive drum  21  with light modulated corresponding to image information to form an electrostatic latent image on a surface of the photosensitive drum  21 . A supply roller  24  is to supply toner to a surface of a developing roller  22 . A regulating member  25  is to form a toner layer of a uniform thickness on the surface of the developing roller  22 . A developing bias voltage may be applied to the developing roller  22 . As the developing roller  22  rotates, toner conveyed to a development nip is moved and adhered, by the developing bias voltage, to the electrostatic latent image formed on the surface of the photosensitive drum  21 , so that a visible toner image is formed on the surface of the photosensitive drum  21 . A print medium P withdrawn from a medium supply device  7  by a pickup roller  71  is transported by a transporting roller  72  to a transfer nip where a transfer roller  5  faces the photosensitive drum  21 . When a transfer bias voltage is applied to the transfer roller  5 , the toner image is transferred to the print medium P by electrostatic attraction. As the toner image transferred to the print medium P is fixed to the print medium P by receiving heat and pressure from a fuser  6 , printing is completed. The print medium P is discharged by a discharge roller  73 . Toner remaining on the surface of the photosensitive drum  21  rather than being transferred to the print medium P is removed by a cleaning member  26 . 
     As illustrated in the examples of  FIGS.  1  and  2   , the developing cartridge  2  may include a developing portion  210  in which the photosensitive drum  21  and the developing roller  22  are installed, a waste toner container  220  in which waste toner removed from the photosensitive drum  21  may be contained, and the toner container  230 , which is connected to the developing portion  210  and in which toner may be contained. The developing cartridge  2  may include a toner refilling portion  10  connected to the toner container  230  to refill the toner container  230  with toner. The toner refilling portion  10  is to provide an interface between the toner refill cartridge  9  and the developing cartridge  2 . The developing cartridge  2  may be an integral developing cartridge including the developing portion  210 , the waste toner container  220 , the toner container  230 , and the toner refilling portion  10 . 
     One or more conveying members  211  may be installed in the developing portion  210  to convey toner toward the developing roller  22 . The conveying member  211  may also agitate toner to charge the toner with a preset electric potential. The waste toner container  220  is spaced upwards from the developing portion  210  to form therebetween a passage  250  for exposure light L irradiated from the optical scanner  4  to the photosensitive drum  21 . Waste toner removed from the photosensitive drum  21  by the cleaning member  26  may be contained in the waste toner container  220 . Waste toner may be transported into the waste toner container  220  by one or more waste toner transporting members  221 ,  222 , and  223 . The toner container  230  may contain toner and is connected to the developing portion  210  by a toner supply portion  234  as indicated by a dashed line in  FIG.  2   . The toner supply portion  234  is located outside an effective width of the exposure light L to avoid interference with the exposure light L scanned in a main scanning direction by the optical scanner  4 . One or more toner supply members  231 ,  232 , and  233  may be installed in the toner container  230  to supply toner to the developing portion  210  through the toner supply portion  234 . The toner supply member  233  may convey toner in the main scanning direction and transfer the toner to the toner supply portion  234 . 
       FIG.  3    is an exploded perspective view of a toner refilling portion according to an example. 
     Referring to  FIG.  3   , the toner refilling portion  10  may include a mounting portion  11  on which the toner refill cartridge  9  may be received, a toner inlet portion  12  for connecting the mounting portion  11  to the toner container  230 , and a toner inlet shutter  13 , which is switchable between a blocking location for blocking the toner inlet portion  12  and an inlet location for opening the toner inlet portion  12 . 
     The mounting portion  11  is connected to the toner container  230 . The toner refill cartridge  9  may be mounted on the mounting portion  11 . The toner inlet portion  12  is connected to the mounting portion  11  to receive toner from the toner refill cartridge  9  and transfer the toner to the toner container  230 . For example, the mounting portion  11  may have a lower body  14  and an upper body  15 . An accommodation portion  151  is provided in the upper body  15  to accommodate a front end of the toner refill cartridge  9 . The upper body  15  is combined with the lower body  14 . The lower body  14  is connected to the toner container  230 . The toner inlet portion  12  is provided in the lower body  14 . 
     The toner inlet shutter  13  may be installed on the lower body  14  to be switched between the blocking location for blocking the toner inlet portion  12  and the inlet location for opening the toner inlet portion  12 . For example, the toner inlet shutter  13  may be installed on the lower body  14  to be rotated between the blocking location and the inlet location. A first cylindrical portion  142  is provided in the lower body  14  to support the toner inlet shutter  13  such that the toner inlet shutter  13  is rotated. The first cylindrical portion  142  may be implemented by a cylindrical rib protruding toward the upper body  15 . The toner inlet shutter  13  is provided with a second cylindrical portion  132  which encloses the first cylindrical portion  142  and is rotatably supported by the first cylindrical portion  142 . The upper body  15  is combined with the lower body  14  to cover the toner inlet shutter  13 . As an example, the toner inlet shutter  13  may include an opening  131 . The lower body  14  may be provided with a toner inlet  141  communicating with the toner inlet portion  12 . The toner inlet shutter  13  may be rotated between the blocking location, for blocking the toner inlet  141  as the opening  131  is misaligned with the toner inlet  141 , and the inlet location, for opening the toner inlet  141  as the opening  131  is aligned with the toner inlet  141 . 
     The toner inlet shutter  13  may be rotated by the driving motor  100 . In an example, the driving motor  100  is provided in the main body  1 . The toner inlet shutter  13  may be provided with a gear portion  133  connected to the driving motor  100 . For example, the lower body  14  may be provided with a gear  16  connected to the driving motor  100 , and the gear portion  133  may engage with the gear  16 . An example structure for driving the toner inlet shutter  13  by using the driving motor  100  will be described later. 
     The toner refilling portion  10  may be provided with a location detecting sensor  17  for detecting a location of the toner inlet shutter  13 . The location detecting sensor  17  may detect the location of the toner inlet shutter  13  using various methods. As an example, the location detecting sensor  17  may include a fixed electrode  171  and a movable electrode  172 . The fixed electrode  171  and the movable electrode  172  may be installed on the lower body  14 . The movable electrode  172  may be elastically changed between a location where the movable electrode  172  interferes with the toner inlet shutter  13  and contacts the fixed electrode  171  and a location where the movable electrode  172  is spaced apart from the fixed electrode  171 . The toner inlet shutter  13  may be provided with an interference portion  134 . When the toner inlet shutter  13  is located at the inlet location, the interference portion  134  may push the movable electrode  172  so that the movable electrode  172  contacts the fixed electrode  171 . For example, the toner inlet shutter  13  may be rotated 180° from the inlet location and switched to the blocking location. In this case, a formation angle of the interference portion  134  may be about 180°. 
       FIG.  4    is a plan view showing a state in which a toner inlet shutter is at an inlet location according to an example, and  FIG.  5    is plan view showing a state in which a toner inlet shutter is at a blocking location according to an example. 
     Referring to  FIG.  4   , as the toner inlet shutter  13  is at the inlet location, the opening  131  is aligned with the toner inlet  141 . Here, the movable electrode  172  interferes with the interference portion  134  and contacts the fixed electrode  171 . This state is referred to as an ON state of the location detecting sensor  17 . In the state shown in  FIG.  4   , the toner inlet shutter  13  is rotated counterclockwise. While the toner inlet shutter  13  is rotated from the inlet location to the blocking location, the movable electrode  172  continuously interferes with the interference portion  134  and remains in contact with the fixed electrode  171 . Therefore, the location detecting sensor  17  remains in the ON state. When the toner inlet shutter  13  is, for example, rotated 180°, as shown in  FIG.  5   , the toner inlet shutter  13  reaches the blocking location, and the opening  131  is misaligned with the toner inlet  141 . When the toner inlet shutter  13  reaches the blocking location, the interference between the interference portion  134  and the movable electrode  172  is ended, and the movable electrode  172  is spaced apart from the fixed electrode  171  by an elastic force as shown in  FIG.  5   . This state is referred to as an OFF state of the location detecting sensor  17 . As described above, when the state of the location detecting sensor  17  is changed from the ON state to the OFF state, the toner inlet shutter  13  may be determined to reach the blocking location. 
     To switch the toner inlet shutter  13  from the blocking location to the inlet location, the toner inlet shutter  13  may be rotated counterclockwise in the state shown in  FIG.  5   . While the toner inlet shutter  13  is rotated from the blocking location to the inlet location, the movable electrode  172  does not interfere with the interference portion  134  and remains spaced apart from the fixed electrode  171 . Therefore, the location detecting sensor  17  remains in the OFF state. When the toner inlet shutter  13  is, for example, rotated 180°, as shown in  FIG.  4   , the toner inlet shutter  13  reaches the inlet location, and the opening  131  and the toner inlet  141  are aligned with each other. When the toner inlet shutter  13  reaches the inlet location, the movable electrode  172  interferes with the interference portion  134 , so that the movable electrode  172  contacts the fixed electrode  171 , and the location detecting sensor  17  is in the ON state again. As described above, when the state of the location detecting sensor  17  is changed from the OFF state to the ON state, the toner inlet shutter  13  may be determined to reach the inlet location. 
     According to an example structure for rotating the toner inlet shutter  13  to the blocking location and the inlet location by using the driving motor  100 , a user does not need to rotate the toner refill cartridge  9 , thereby improving user convenience. Also, as the location of the toner inlet shutter  13  may be reliably detected using the location detecting sensor  17 , the toner inlet shutter  13  may accurately be at the blocking location or the inlet location by controlling the driving motor  100  on the basis of a detection signal of the location detecting sensor  17 . Therefore, compared to a structure in which a user opens the toner inlet shutter  13  by rotating the toner refill cartridge  9 , a breakage caused by an excessive rotation of the toner inlet shutter  13  and toner leakage caused by an insufficient rotation of the toner inlet shutter  13  may be reduced or prevented. 
       FIG.  6    is a block diagram showing a driving structure for rotating a toner inlet shutter by using a driving motor according to an example. 
     Referring to  FIG.  6   , the driving motor  100  and the clutch  110  may be connected to each other by one or more gears. The driving motor  100  may drive a rotation member provided in the main body  1 . For example, the driving motor  100  may drive the transfer roller  5 , the pickup roller  71 , the fuser  6 , or the discharge roller  73 . The driving motor  100  may be connected to the rotation member provided in the main body  1  by a gear train (not shown). The driving motor  100  may drive a rotation member of the developing cartridge  2 . For example, the driving motor  100  may drive the photosensitive drum  21 , the developing roller  22 , the charging roller  23 , the supply roller  24 , the conveying member  211 , the waste toner transporting members  221 ,  222 , and  223 , or the toner supply members  232 ,  232 , and  233 . The driving motor  100  may be connected to a rotation member of the developing cartridge  2  by a gear train (not shown). A rotation shaft of a rotation member may protrude to the outside by passing through one side portion of the developing cartridge  2 , and a protruding end of the rotation shaft may be combined, for example, with a gear connected to the gear train. In an example, a driving force of the driving motor  100  may be selectively transmitted to the toner inlet shutter  13  by using the clutch  110 . The clutch  110  may selectively transmit the driving force of the driving motor  100  to the toner inlet shutter  13  and a rotation member. For example, the clutch  110  may selectively transmit the driving force to the toner inlet shutter  13  and a rotation member according to a rotation direction of the driving motor  100 . 
     The clutch  110  may include a first clutch  110 - 1  for selectively transmitting the driving force of the driving motor  110  to the toner inlet shutter  13 . For example, the first clutch  110 - 1  may be between a first connecting gear  401  and the driving motor  100 . The first connecting gear  401  may be connected to the gear  16  engaging with the gear portion  133  of the toner inlet shutter  13 . The clutch  110  may include a second clutch  110 - 2  for selectively transmitting the driving force of the driving motor  100  to a rotation member, for example, to a rotation member of the developing cartridge  2 . For example, the second clutch  110 - 2  may be between a second connecting gear  402  and the driving motor  100 . The second connecting gear  402  may be connected to a rotation member of the developing cartridge  2 . 
     The first clutch  110 - 1  and the second clutch  110 - 2  may each have various structures. For example, the first clutch  110 - 1  and the second clutch  110 - 2  may each include a one-way clutch for selectively transmitting the driving force of the driving motor  100  to the toner inlet shutter  13  and a rotation member of the developing cartridge  2  according to a rotation direction of the driving motor  100 . The first clutch  110 - 1  may transmit the driving force to the toner inlet shutter  13  when the driving motor  100  is rotated in a first direction, and the second clutch  110 - 2  may transmit the driving force to a rotation member when the driving motor  100  is rotated in a second direction, which is an opposite direction of the first direction. 
       FIG.  7    is an exploded perspective view of a one-way clutch according to an example.  FIGS.  8  and  9    are schematic views showing an operation of the one-way clutch shown in  FIG.  7    according to various examples. 
     Referring to  FIGS.  7  through  9   , a one-way clutch  400  may include an input member  410 , an output member  420 , and a clutch bush  430  between the input member  410  and the output member  420 . In an example, the one-way clutch  400  has a structure in which, when the input member  410  is rotated in a direction A 1 , the output member  420  is rotated in the direction A 1 , and, when the input member  410  is rotated in a direction A 2 , the output member  420  is not rotated. 
     The clutch bush  430  is supported on the output member  420  to be axially moved. For example, the output member  420  may be provided with a boss  424  extending axially, and the clutch bush  430  may be provided with a penetration portion  434  into which the boss  424  may be inserted. The input member  410  may be connected to the driving motor  100 . The input member  410  is to rotate the clutch bush  430 . For example, the input member  410  may be provided with driving ribs  411   a  and  411   b  extending radially. The clutch bush  430  may be provided with driven ribs  435   a  and  435   b  facing the driving ribs  411   a  and  411   b  in a rotation direction. Therefore, when the input member  410  is rotated, the driving ribs  411   a  and  411   b  push the driven ribs  435   a  and  435   b,  and the clutch bush  430  is rotated in the same direction as the input member  410 . A first clutch portion  433  may be provided on the opposite side of the driven ribs  435   a  and  435   b  of the clutch bush  430 . The output member  420  may be provided with a second clutch portion  423  to engage with the first clutch portion  433 . The first clutch portion  433  may have a shape in which a first locking portion  431  and a first inclined portion  432  are repeatedly arranged in a circumferential direction, and the second clutch portion  423  may have a shape in which a second locking portion  421  and a second inclined portion  422  respectively facing the first locking portion  431  and the first inclined portion  432  are repeatedly arranged in the circumferential direction. A facing surface  412  of the input member  410  axially facing the driven ribs  435   a  and  435   b  is an axially inclined surface. The facing surface  412  may have a structure in which the clutch bush  430  is pushed toward the output member  420  when the input member  410  is rotated in the direction A 1 . For example, the facing surface  412  between the driving ribs  411   a  and  411   b  may be an inclined surface protruding toward the output member  420  when being rotated in the direction A 1 .  FIGS.  8  and  9    conceptually illustrate that the facing surface  412  has an inclined shape. 
     As shown in  FIG.  8    when the input member  410  is rotated in the direction A 1 , the facing surface  412  contacts the driven ribs  435   a  and  435   b  of the clutch bush  430  and pushes the driven ribs  435   a  and  435   b  toward the output member  420 . When the driving ribs  411   a  and  411   b  contact the driven ribs  435   a  and  435   b,  the clutch bush  430  is rotated in the direction A 1 . The first locking portion  431  and the second locking portion  421  face each other, and the first locking portion  431  pushes the second locking portion  421  in the direction A 1 . Therefore, the output member  420  is rotated in the direction A 1 . 
     As shown in  FIG.  9   , when the input member  410  is rotated in the direction A 2 , the driving ribs  411   a  and  411   b  are spaced apart from the driven ribs  435   a  and  435   b,  and the clutch bush  430  is not rotated. The facing surface  412  is axially spaced apart from the driven ribs  435   a  and  435   b.  When the driving ribs  411   a  and  411   b  respectively contact the driven ribs  435   a  and  435   b,  the clutch bush  430  is rotated in the direction A 2 . The first locking portion  431  is spaced apart from the second locking portion  421  in the direction A 2 , and the first inclined portion  422  and the second inclined portion  432  contact each other. The clutch bush  430  is pushed toward the input member  410  by the first inclined portion  422  and the second inclined portion  432 , and the first clutch portion  433  is spaced apart from the second clutch portion  423 . Therefore, the output member  420  is not rotated. 
     The one-way clutch  400  shown in  FIGS.  7  through  9    may be applied as the first clutch  110 - 1 . In this case, the input member  410  may be connected to the driving motor  100 , and the output member  420  may be connected to the toner inlet shutter  13  through the first connecting gear  401 . For example, when the driving motor  100  is rotated in a first direction, the input member  410  and the output member  420  are rotated together in the direction A 1  to rotate the toner inlet shutter  13  between a blocking location and an inlet location. When the driving motor  100  is rotated in a second direction, the input member  410  is rotated in the direction A 2  but the output member  420  is not rotated, and thus, a driving force of the driving motor  100  is not transmitted to the toner inlet shutter  13 . Although not shown in the drawings, an electronic clutch may be applied as the first clutch  110 - 1  to selectively transmit the driving force of the driving motor  100  to the toner inlet shutter  13  by an electrical signal. 
       FIG.  10    is a schematic configuration diagram of a one-way clutch according to an example. An example one-way clutch  400   a  differs from the one-way clutch  400  shown in  FIGS.  7  through  9    in having a structure in which, when an input member  410   a  is rotated in a direction A 2 , an output member  420   a  is rotated in the direction A 2 , and, when the input member  410   a  is rotated in a direction A 1 , the output member  420   a  is not rotated. Hereinafter, differences therebetween will be mainly described. 
     Referring to  FIG.  10   , a clutch bush  430   a  is supported by the output member  420   a  to be axially moved. The input member  410   a  may be connected to the driving motor  100 . The input member  410   a  is to rotate the clutch bush  430   a.  The clutch bush  430   a  may be provided with a first clutch portion  433   a,  and the output member  420   a  may be provided with a second clutch portion  423   a  to engage with the first clutch portion  433   a.  The first clutch portion  433   a  may have a shape in which a first locking portion  431   a  and an inclined portion  432   a  are repeatedly arranged in a circumferential direction, and the second clutch portion  423   a  may have a shape in which a second locking portion  421   a  and a second inclined portion  422   a  respectively facing the first locking portion  431   a  and the first inclined portion  432   a  are repeatedly arranged in the circumferential direction. A facing surface  412   a  of the input member  410   a  may have an inclined surface protruding toward the output member  420   a  when being rotated in the direction A 2  to push the clutch bush  430   a  toward the output member  420   a  when the input member  410   a  is rotated in the direction A 2 . In other words, the first clutch portion  433   a,  the second clutch portion  423   a,  and the facing surface  412   a  are respectively symmetrical to the first clutch portion  433 , the second clutch portion  423 , and the facing surface  412   a  shown in  FIGS.  7  through  9   . Therefore, when the input member  410   a  is rotated in the direction A 1 , the output member  420   a  may not be rotated. When the input member  410   a  is rotated in the direction A 2 , the output member  420   a  may also be rotated in the direction A 2 . 
     The one-way clutch  400   a  shown in  FIG.  10    may be applied as the second clutch  110 - 2 . In this case, the input member  410   a  may be connected to the driving motor  100 , and the output member  420   a  may be connected to a rotation member of the developing cartridge  2  through the second connecting gear  402 . For example, when the driving motor  100  is rotated in a first direction, the input member  410   a  is rotated in the direction A 1  but the output member  420   a  is not rotated so that a driving force of the driving motor  100  is not transmitted to the rotation member of the developing cartridge  2 . When the driving motor  100  is rotated in a second direction, the input member  410   a  and the output member  420   a  may be rotated together in the direction A 2  so that the driving force of the driving motor  100  may be transmitted to a rotation member of the developing cartridge  2 . Although not shown in the drawings, an electronic clutch may be applied as the second clutch  110 - 2  to selectively transmit the driving force of the driving motor  100  to the rotation member of the developing cartridge  2  by an electrical signal. 
     According to an example structure for selectively transmitting the driving force of the driving motor  100  to the toner inlet shutter  13  by using the clutch  110 , the toner inlet shutter  13  may be driven by using the driving motor  100  for driving a rotation member of the developing cartridge  2 . Therefore, an additional driving motor for driving the toner inlet shutter  13  does not need to be applied, and thus, manufacturing cost of an image forming apparatus may be reduced. 
     As described above, when toner contained in the toner container  230  is consumed, the toner container  230  may be provided with new toner by using the toner refill cartridge  9 . An example electrophotographic image forming apparatus has a structure in which the toner refill cartridge  9  is inserted from the outside of the main body  1  into the main body  1  to be mounted on the toner refilling portion  10  and separated from the main body  1  after the toner container  230  is provided with toner. For this, referring to  FIG.  1   , the main body  1  is provided with a communicating portion  8  for allowing the toner refill cartridge  9  to access the toner refilling portion  10  from the outside of the main body  1 . The toner refill cartridge  9  is removed from the communicating portion  8  after toner is provided. According to an example structure described above, the toner container  230  may be provided with toner through the toner refiling portion  10 . Therefore, a replacement time of the developing cartridge  2  may be extended until the lifespan of the photosensitive drum  21  is terminated, thereby reducing printing cost per sheet. Because toner may be provided while the developing cartridge  2  is mounted in the main body  1 , user convenience may be improved. 
       FIG.  11    is a schematic partial exploded perspective view of a toner refill cartridge according to an example. 
     Referring to  FIGS.  1  and  11   , the toner refill cartridge  9  may be a syringe-shaped toner refill cartridge having a body  91  in which toner is contained and a plunger  92 , which is moveably combined with the body  91  in a longitudinal direction B to push toner to the outside of the body  91 . A front end  911  of the body  91  is provided with a toner outlet  93  through which toner may be discharged from the body  91 . When the plunger  92  is pressed in the longitudinal direction B while the toner refill cartridge  9  is mounted on the toner refilling portion  10 , toner contained in the body  91  may be supplied to the toner container  230  of the developing cartridge  2  through the toner refilling portion  10 . 
     A toner outlet shutter  94  is installed at the front end  911  of the body  91  to be switched between an outlet location for opening the toner outlet  93  and a closing location for closing the toner outlet  93 . For example, the toner outlet shutter  94  may be rotated between the outlet location and the closing location. An opening  941  is provided in the toner outlet shutter  94 . The toner outlet  93  and the opening  941  are aligned with each other at the outlet location, and the toner outlet  93  and the opening  941  are misaligned with each other at the closing location. 
     The toner outlet shutter  94  may be connected to the toner inlet shutter  13  to be rotated. The toner inlet shutter  13  may be connected to the toner outlet shutter  94  to be rotated between a blocking location for blocking the toner outlet  93  and the toner inlet portion  12  and an inlet location for opening the toner outlet  93  and the toner inlet portion  12 . In other words, the toner outlet shutter  94  may be rotated together with the toner inlet shutter  13  between the outlet location and the closing location. 
     When the toner refill cartridge  9  is mounted on the toner refilling portion  10  through the communicating portion  8  of the main body  1 , the front end  911  of the body  91  may be inserted into the accommodation portion  151  provided in the toner refilling portion  10 , and the toner outlet shutter  94  may be connected to the toner inlet shutter  13 . For example, referring to  FIGS.  4  and  11   , a first connecting portion  135  and a second connecting portion  95  are respectively provided in the toner inlet shutter  13  and the toner outlet shutter  94 . When the toner refill cartridge  9  is mounted on the toner refilling portion  10 , the first connecting portion  135  and the second connecting portion  95  are connected to each other. The first connecting portion  135  and the second connecting portion  95  are connected to each other so that the toner outlet shutter  94  and the toner inlet shutter  13  are rotated together. For example, the first connecting portion  135  may include a pair of protrusions, and the second connecting portion  95  may include a pair of holes into which the pair of protrusions are inserted. 
     The toner refill cartridge  9  may be inserted into the main body  1  through the communicating portion  8  and mounted on the toner refilling portion  10  while the toner outlet shutter  94  is located at the closing location. The toner inlet shutter  13  is at the blocking location. The toner outlet  93  is aligned with the toner inlet  141 . The first connecting portion  135  and the second connecting portion  95  are connected to each other. The toner outlet shutter  94  is at the closing location, and the toner inlet shutter  13  is at the blocking location. Therefore, toner of the toner refill cartridge  9  may not be discharged to the toner refilling portion  10 . The driving motor  100  is rotated in a first direction to open the toner outlet  93  and the toner inlet  141 . A driving force of the driving motor  100  is transmitted to the toner inlet shutter  13  by the first clutch  110 - 1 , and the toner inlet shutter  13  is rotated from the blocking location to the inlet location. The second clutch  110 - 2  blocks the driving force of the driving motor  100 . Therefore, the driving force of the driving motor  100  is not transmitted to a rotation member of the developing cartridge  2 . The toner outlet shutter  94  is rotated together with the toner inlet shutter  13  from the closing location to the outlet location. When the toner inlet shutter  13  reaches the inlet location, the toner outlet shutter  94  reaches the outlet location. The movable electrode  172  is pushed by the interference portion  134  provided in the toner inlet shutter  13  and contacts the fixed electrode  171 , and a state of the location detecting sensor  17  is changed from an OFF state to an ON state. Driving of the driving motor  100  is stopped. The toner outlet  93 , the opening  941  of the toner outlet shutter  94 , the opening  131  of the toner inlet shutter  13 , and the toner inlet  141  are sequentially aligned. Toner inside the body  91  may be discharged to the toner refilling portion  10  through the toner outlet  93  and the opening  941  by pressing the plunger  92  in the longitudinal direction B. Toner passes the toner inlet portion  12  through the opening  131  of the toner inlet shutter  13  and the toner inlet  141  and is provided to the toner container  230  of the developing cartridge  2 . When the plunger  92  reaches a lower location, toner refilling is completed. 
     Before the toner refill cartridge  9  is separated from the toner refilling portion  10 , the driving motor  100  is rotated in the first direction. The driving force of the driving motor  100  is transmitted to the toner inlet shutter  13  by the first clutch  110 - 1 , and the toner inlet shutter  13  is rotated from an opening location to the blocking location. The toner outlet shutter  94  is rotated together with the toner inlet shutter  13  from the outlet location to the closing location. When the toner inlet shutter  13  reaches the blocking location, the outlet shutter  94  reaches the closing location. The interference between the interference portion  134  and the movable electrode  172  is ended, and the movable electrode  172  is spaced apart from the fixed electrode  171 . The state of the location detecting sensor  17  is changed from the ON state to the OFF state. Driving of the driving motor  100  is stopped. The toner refill cartridge  9  may be separated from the toner refilling portion  10 . 
     The driving motor  100  may be rotated in the second direction to perform a print job. The driving force of the driving motor  100  may be transmitted to a rotation member of the developing cartridge  2  by the second clutch  110 - 2 . Because the driving force of the driving motor  100  is not transmitted by the first clutch  110 - 1 , the toner inlet shutter  13  is not rotated and remains at the blocking location. 
     It should be understood that examples described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each example should typically be considered as available for other similar features or aspects in other examples. While one or more examples have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims.