Patent Publication Number: US-11397390-B2

Title: Toner refill cartridge with a spiral portion to move a plunger

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 directly or through an intermediate transfer medium, and fixes the transferred toner image to the print medium. 
     A developing cartridge accommodates toner and supplies the toner to an electrostatic latent image formed on the photoconductor to form a visible toner image. When the toner accommodated in the developing cartridge is used up, the developing cartridge may be removed from a main body of the image forming apparatus, and a new developing cartridge may be mounted on the main body. A toner refill cartridge may also be used to fill the developing cartridge with new toner. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic external perspective view of an electrophotographic image forming apparatus according to an example. 
         FIG. 2  is a schematic block diagram of an electrophotographic image forming apparatus according to an example. 
         FIG. 3  is a perspective view of a developing cartridge according to an example. 
         FIG. 4  is an exploded perspective view of a toner refill cartridge according to an example. 
         FIG. 5  is a cross-sectional view of a toner refill cartridge showing a state in which a plunger is located at a top dead position according to an example. 
         FIG. 6  is a cross-sectional view of a toner refill cartridge showing a state in which a plunger is located at a bottom dead position according to an example. 
         FIG. 7  is a cross-sectional view of a toner refill cartridge showing a state in which a plunger is located at a top dead position according to an example. 
         FIG. 8  is a cross-sectional view of a toner refill cartridge showing a state in which a plunger is located at a bottom dead position according to an example. 
         FIG. 9  is a perspective view of a toner refill cartridge showing a state in which an extension handle is positioned at a first position according to an example. 
         FIG. 10  is a perspective view of a toner refill cartridge showing a state in which an extension handle is positioned at a second position according to an example. 
     
    
    
     DETAILED DESCRIPTION OF EXAMPLES 
     Reference will now be made to examples that are illustrated in the accompanying drawings. The same reference numerals are used to denote the same elements, and repeated descriptions thereof will not be given herein. 
       FIG. 1  is a schematic external perspective view of an electrophotographic image forming apparatus according to an example.  FIG. 2  is a schematic block diagram of an electrophotographic image forming apparatus according to an example.  FIG. 3  is a perspective view of a developing cartridge according to an example. 
     Referring to  FIGS. 1, 2, and 3 , an electrophotographic image forming apparatus may include a main body  1  and a developing cartridge  2  in a cartridge form detachable from the main body  1 . A door  3  may be provided in the main body  1 . The door  3  may open and close a part of the main body  1 . In the example of  FIG. 1 , the door  3  opens an upper part of the main body  1 . However, a door which opens a side part or a front part of the main body  1  may be employed as needed. The developing cartridge  2  may be mounted on and/or detached from the main body  1  by opening the door  3 . 
     A photosensitive drum  21  is one example of a photoconductor on which an electrostatic latent image may be formed. The photosensitive drum  21  may include a cylindrical metal pipe and a photosensitive layer having photoconductivity formed on an outer circumference thereof. A charging roller  23  is one example of a charger to charge the surface of the photosensitive drum  21  to a uniform electric potential. A charging bias voltage may be applied to the charging roller  23 . In an example, a corona charger (not shown) may be used instead of the charging roller  23 . A developing roller  22  may supply toner to an electrostatic latent image formed on the surface of the photosensitive drum  21  and develop the electrostatic latent image. 
     In the case of a two-component developing method using toner and a carrier as a developing agent, the developing roller  22  may include a rotatable sleeve and a magnet fixedly (e.g., not to be rotated) installed on the inner side of the sleeve. The sleeve may be spaced several tens to hundreds of micrometers apart from the photosensitive drum  21 . The carrier may be attached to an outer circumference of the developing roller  22  by a magnetic force of the magnet, and the toner may be attached to the carrier by an electrostatic force, such that a magnetic brush made of the carrier and the toner is formed on the outer circumference of the developing roller  22 . Only the toner is moved to the electrostatic latent image formed on the photosensitive drum  21  by the developing bias voltage applied to the developing roller  22 . 
     In the case of a one-component developing method using toner as a developing agent, the developing roller  22  may be in contact with the photosensitive drum  21  or may be spaced several tens to hundreds of micrometers apart from the photosensitive drum  21 . In this example, a one-component contact developing method is adopted in which the developing roller  22  and the photosensitive drum  21  are in contact with each other to form a development nip. The developing roller  22  may have an elastic layer (not shown) formed on an outer circumference of a conductive metal core (not shown). When the developing bias voltage is applied to the developing roller  22 , the toner is moved and attached to the electrostatic latent image formed on the photosensitive drum  21  through the development nip. 
     A supply roller  24  may attach the toner to the developing roller  22 . A supply bias voltage may be applied to the supply roller  24  to attach the toner to the developing roller  22 . A regulating member  25  is provided to regulate an amount of toner attached to the surface of the developing roller  22 . The regulating member  25  may be, for example, a regulating blade having a tip that is in contact with the developing roller  22 . A cleaning member  26  is provided to remove residual toner and foreign matter from the surface of the photosensitive drum  21  before charging. The cleaning member  26  may be, for example, a cleaning blade whose tip is in contact with the surface of the photosensitive drum  21 . Hereinafter, the foreign substance removed from the surface of the photosensitive drum  21  is referred to as waste toner. 
     An optical scanner  4  may irradiate light modulated according to image information onto the surface of the photosensitive drum  21  charged at a uniform electric potential. For example, a laser scanning unit (LSU) which scans the photosensitive drum  21  by deflecting light emitted from a laser diode in a main scanning direction using a polygon mirror may be employed as the optical scanner  4 . 
     A transfer roller  5  is one example of a transfer unit which is positioned to face the photosensitive drum  21  to form a transfer nip. A transfer bias voltage for transferring a toner image developed on the surface of the photosensitive drum  21  to a print medium P is applied to the transfer roller  5 . A corona transfer unit may be used instead of the transfer roller  5 . 
     The toner image transferred to the surface of the print medium P by the transfer roller  5  is maintained on the surface of the print medium P by electrostatic attraction. A fusing unit  6  forms a permanent printed image on the print medium P by applying heat and pressure to the toner image to be fixed on the print medium P. 
     Referring to  FIGS. 2 and 3 , 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 chamber  220  to accommodate waste toner removed from the photosensitive drum  21 , and a toner accommodating portion  230  connected to the developing portion  210  to accommodate the toner. To refill the toner in the toner accommodating portion  230 , the developing cartridge  2  is provided with a toner filling portion  10  connected to the toner accommodating portion  230 . The toner filling portion  10  provides an interface between a toner refill cartridge  9  and the developing cartridge  2 . The developing cartridge  2  may be an integrated developing cartridge including the developing portion  210 , the waste toner chamber  220 , the toner accommodating portion  230 , and the toner filling portion  10 . 
     A part of an outer circumference of the photosensitive drum  21  is exposed to an outer side of a housing of the developing cartridge  2 . The transfer roller  5  may be in contact with the exposed part of the photosensitive drum  21  to form a transfer nip. One or more conveying members for conveying the toner toward the developing roller  22  may be installed in the developing portion  210 . The conveying member may serve to stir the toner to charge the toner to a certain electric potential. 
     The waste toner chamber  220  is positioned at an upper side of the developing portion  210 . The waste toner chamber  220  is spaced upward from the developing portion  210  to form an optical path  250  therebetween. The waste toner removed from the photosensitive drum  21  by the cleaning member  26  is accommodated in the waste toner chamber  220 . The waste toner removed from the photosensitive drum  21  is transferred into the waste toner chamber  220  by one or more waste toner conveying members  221 ,  222 , and  223 . The shape and number of waste toner conveying members are not particularly limited. An appropriate number of waste toner conveying members may be installed at appropriate positions to effectively disperse the waste toner inside the waste toner chamber  220  in consideration of the volume or shape of the waste toner chamber  220 . 
     The toner accommodating portion  230  is connected to the toner filling portion  10  to accommodate the toner. The toner accommodating portion  230  is connected to the developing portion  210  by a toner supply portion  234  as shown by a dotted line in  FIG. 2 . As shown in  FIG. 2 , the toner supply portion  234  may be connected to the developing portion  210  by penetrating the waste toner chamber  220  in a vertical direction. The toner supply portion  234  is located outside an effective width of an exposure light L so as not to interfere with the exposure light L scanned in the main scanning direction by the optical scanner  4 . 
     The toner accommodating portion  230  may be provided with one or more toner supply members  231 ,  232 , and  233  for supplying the toner to the developing portion  210  through the toner supply portion  234 . The shape and number of toner supply members are not particularly limited. An appropriate number of toner supply members may be installed at an appropriate position in the toner accommodating portion  230  to effectively supply the toner to the developing portion  210  in consideration of the volume or shape of the toner accommodating portion  230 . The toner supply member  233  may transfer the toner in the main scanning direction to the toner supply portion  234 . 
     An example image forming process configured as above will be briefly described. A charging bias is applied to the charging roller  23  and the photosensitive drum  21  is charged to a uniform electric potential. The optical scanner  4  scans the light modulated in correspondence with image information to the photosensitive drum  21  and forms an electrostatic latent image on the surface of the photosensitive drum  21 . The supply roller  24  attaches the toner to the surface of the developing roller  22 . The regulating member  25  forms a toner layer of a uniform thickness on the surface of the developing roller  22 . A developing bias voltage is applied to the developing roller  22 . As the developing roller  22  is rotated, the toner conveyed to the development nip is moved and attached to the electrostatic latent image formed on the surface of the photosensitive drum  21  by the developing bias voltage so that a visible toner image is formed on the surface of the photosensitive drum  21 . The print medium P drawn out from a loading device  7  by a pickup roller  71  is transferred by a transport roller  72  to the development nip where the transfer roller  5  and the photosensitive drum  21  are opposed to each other. When the transfer bias voltage is applied to the transfer roller  5 , the toner image is transferred to the print medium P by electrostatic attraction. The toner image transferred to the print medium P is fixed to the print medium P by receiving heat and pressure from the fusing unit  6 , thereby completing printing. The print medium P is discharged by a discharge roller  73 . Toner remaining on the surface of the photosensitive drum  21  without being transferred to the print medium P is removed by the cleaning member  26 . 
     As described above, the developing cartridge  2  may supply toner accommodated in the toner accommodating portion  230  to the electrostatic latent image formed on the photosensitive drum  21  to form a visible toner image. The developing cartridge  2  may be attached to and detached from the main body  1 . In addition, the developing cartridge  2  is provided with the toner filling portion  10  capable of refilling the toner. The toner filling portion  10  is integrally formed with the developing cartridge  2  to be attached to or detached from the main body  1  together with the developing cartridge  2 . According to the image forming apparatus in the present example, the toner may be refilled in the developing cartridge  2  in a state in which the developing cartridge  2  is mounted on the main body  1  without removing the developing cartridge  2  from the main body  1 . 
     Referring again to  FIG. 1 , the toner refill cartridge  9  comprises a body  91  to accommodate toner and a toner discharge port  94 . The toner discharge port  94  is provided at one end in a longitudinal direction A. The main body  1  is provided with a communication portion  8  so that the toner filling portion  10  may be accessed from the outside of the main body  1  in a state in which the developing cartridge  2  is attached to the main body  1 . The communication portion  8  may be provided at a position close to a front portion  1 - 2  of the main body  1 . As the front portion  1 - 2  faces a user, the user may easily access the communication portion  8 . Therefore, the toner refilling operation through the communication portion  8  may be easily performed. The communication portion  8  may be provided on an upper surface  1 - 1  of the main body  1 . The toner filling portion  10  is positioned at a lower part of the communication portion  8 . The communication portion  8  and the toner filling portion  10  may be aligned with each other in a vertical direction. The toner refill cartridge  9  may access the toner filling portion  10  through the communication portion  8  from the upper side of the main body  1 . 
     For example, when the toner refill cartridge  9  is inserted into the communication portion  8  from the upper side of the main body  1 , as shown in  FIG. 3 , the toner refill cartridge  9  may be connected to the toner filling portion  10 . When toner inside the body  91  is discharged through the toner discharge port  94  in this state, the toner may be supplied to the toner accommodating portion  230  of the developing cartridge  2  through the toner filling portion  10 . The toner refill cartridge  9  is removed from the communication portion  8  after the toner is refilled. 
     According to this configuration, since the toner may be refilled in the toner accommodating portion  230  through the toner filling portion  10 , the replacement timing of the developing cartridge  2  may be extended until the life of the photosensitive drum  21  is reached, so that the printing cost per sheet may be reduced. The toner may be refilled in a state in which the developing cartridge  2  is mounted on the main body  1 , thereby improving user convenience. 
     As a method of discharging toner from the toner refill cartridge  9 , a syringe method using a plunger (not shown) movable in the longitudinal direction A inside the body  91  may be employed. After the toner refill cartridge  9  is mounted on the communication portion  8  of the main body  1 , the plunger may be pressed in the longitudinal direction A to refill the toner in the developing cartridge  2 . The discharge speed of the toner through the toner discharge port  94  is proportional to the speed at which the plunger is pressed. If the plunger is pressed too quickly, an excessive amount of toner may be filled into the developing cartridge  2  at once. Also, the internal pressure of the developing cartridge  2  may be increased, and toner may leak through a weakly sealed part of the developing cartridge  2 . 
     The toner refill cartridge  9  in this example has a structure in which the toner is discharged at an appropriate speed. 
       FIG. 4  is an exploded perspective view of a toner refill cartridge according to an example.  FIG. 5  is a cross-sectional view of a toner refill cartridge showing a state in which a plunger is located at a top dead position according to an example.  FIG. 6  is a cross-sectional view of a toner refill cartridge showing a state in which a plunger is located at a bottom dead position according to an example. 
     Referring to  FIGS. 4 to 6 , the toner refill cartridge  9  may include the body  91 , a first member  97 , a second member  96 , and a plunger  93 . 
     The body  91  comprises a toner accommodating portion  92  to accommodate toner and a toner discharge port  94  communicating with the toner accommodating portion  92  at an end portion  911  in the longitudinal direction A. The toner accommodating portion  92  communicates with the outside through the toner discharge port  94 . A shutter  95  for selectively opening and closing the toner discharge port  94  may be provided at the end portion  911  of the body  91 . For example, the shutter  95  may open the toner discharge port  94  in conjunction with an operation in which the toner refill cartridge  9  is mounted on the toner filling portion  10 . 
     The first member  97  may be provided with a spiral portion  971  supported by the body  91  to be rotated and extending in the longitudinal direction A. The first member  97  may be inserted into the body  91  and may be supported by the body  91  to be rotated. The first member  97  may have a hollow cylindrical shape. The spiral portion  971  may be provided on an inner wall  972  of the first member  97 . The spiral portion  971  extends in the longitudinal direction A. The first member  97  may include a handle  98  exposed to the outside of the body  91  so as to rotate the first member  97 . The handle  98  is exposed to the outside of the body  91  through an end portion  912  of the body  91  to be held by a user&#39;s hand. The handle  98  may be integrally formed with the first member  97  or may be manufactured as a separate member and coupled to the first member  97 . 
     The second member  96  is positioned inside the first member  97 . A guide groove  961  extending in the longitudinal direction A is provided in the second member  96 . The second member  96  may have a hollow cylindrical shape. The guide groove  961  may be formed by penetrating a side wall  962  of the second member  96 . 
     The plunger  93  may be inserted into the second member  96 . The plunger  93  has a guide protrusion  933  which passes through the guide groove  961  and couples with the spiral portion  971 . The guide protrusion  933  may be provided near an end of the plunger  93  away from the toner accommodating portion  92 . The plunger  93  may be moved in the longitudinal direction A as the first member  97  is rotated to push toner in the toner accommodating portion  92  toward the toner discharge port  94 . 
     The toner refill cartridge  9  in this example has a structure in which the toner accommodating portion  92  is formed by the body  91 . The body  91  has a first portion  91 - 1  and a second portion  91 - 2 . The first portion  91 - 1  and the second portion  91 - 2  extend in the longitudinal direction A. The first portion  91 - 1  comprises the toner accommodating portion  92 . The toner discharge port  94  is provided at the end portion  911  of the first portion  91 - 1 . The second portion  91 - 2  accommodates the first member  97 , the second member  96 , and the plunger  93 . The second portion  91 - 2  extends in an opposite direction of the toner discharge port  94  from the first portion  91 - 1 . The handle  98  is exposed to the outside through the end portion  912  of the second portion  91 - 2 . 
     The plunger  93  may include a piston  931  and a packing member  932 . The piston  931  includes the guide protrusion  933 . The guide protrusion  933  may be provided near an end of the plunger  93  opposite to the packing member  932 . The piston  931  extends from the inner side of the second member  96  to the inner side of the toner accommodating portion  92 . A communication port  963  through which the piston  931  passes is provided at an end of the second member  96  on the toner accommodating portion  92 . The packing member  932  is provided at an end of the piston  931 , that is, the end on the toner accommodating portion  92 . The packing member  932  is in contact with an inner wall of the toner accommodating portion  92 . The packing member  932  pushes the toner contained in the toner accommodating portion  92  toward the toner discharge port  94  when the plunger  93  is moved in the longitudinal direction A toward the end portion  911 . The packing member  932  may be formed of an elastic material such as rubber which elastically contacts the inner wall of the toner accommodating portion  92 . 
     As shown in  FIG. 4 , the plunger  93  may be inserted into the second member  96 , the second member  96  may be inserted into the first member  97 , and the first member  97  may be inserted into the second portion  91 - 2  of the body  91 . 
     The guide protrusion  933  penetrates through a side wall  962  of the second member  96  through the guide groove  961  to protrude from the side wall  962  and engages with the spiral portion  971 . The packing member  932  is positioned in the toner accommodating portion  92 . The plunger  93  is located at a top dead position Q 1  in which the packing member  932  is located at a position away from the toner discharge port  94 . 
     In this state, when the toner refill cartridge  9  is inserted into the communication portion  8  as shown in  FIG. 1 , the toner refill cartridge  9  is connected to the toner filling portion  10  as shown in  FIG. 3 . The handle  98  is exposed to the outside of the body  91  through the end portion  912  of the body  91 . When the handle  98  is turned, the first member  97  is rotated. Thrust in the longitudinal direction A is generated in the guide protrusion  933  by the spiral portion  971 . Since the guide protrusion  933  is inserted into the guide groove  961  extending in the longitudinal direction A, the guide protrusion  933  is guided to the guide groove  961  and moved in the longitudinal direction A. The packing member  932  pushes the toner contained in the toner accommodating portion  92  to the outside through the toner discharge port  94 . The toner discharged from the toner discharge port  94  may pass through the toner filling portion  10  and be accommodated in the toner accommodating portion  230  in the developing cartridge  2 . When the packing member  932  reaches a bottom dead position Q 2  as shown in  FIG. 6 , toner filling is completed. 
     The maximum angle at which the user may hold the handle  98  and rotate the first member  97  at one time may not exceed 360 degrees, and generally does not exceed about 180 degrees. Therefore, if the pitch of the spiral portion  971  is appropriately selected, a sudden movement of the plunger  93  may be prevented. In addition, if the cross-sectional area of the toner accommodating portion  92  is appropriately selected, a sudden discharge of the toner may be prevented. 
     For example, if the pitch of the spiral portion  971  is 40 mm and the user rotates the first member  97  180 degrees at a time, the plunger  93  may be moved 20 mm by a rotational operation of rotating the handle  98  once. If the cross-sectional area of the toner accommodating portion  92  is about 400 mm 2 , about 8 cc of toner is filled into the developing cartridge  2  by one rotational operation. If the length of the toner accommodating portion  92  is 200 mm, ten rotational operations are required to move the plunger  93  from the top dead position Q 1  to the bottom dead position Q 2 . Therefore, since the plunger  93  is moved from the top dead position Q 1  to the bottom dead position Q 2  by the rotational operation divided into ten times, a sudden discharge of the toner and consequently a toner leakage in the developing cartridge  2  may be prevented. 
       FIG. 7  is a cross-sectional view of a toner refill cartridge showing a state in which a plunger is located at a top dead position according to an example.  FIG. 8  is a cross-sectional view of a toner refill cartridge showing a state in which a plunger is located at a bottom dead position according to an example. 
     Referring to  FIGS. 7 and 8 , a toner refill cartridge  9   a  comprises a body  91   a , a first member  97   a , a handle  98 , a second member  96   a , and a plunger  93   a . Compared to the toner refill cartridge  9  shown in  FIGS. 4 to 6 , the toner refill cartridge  9   a  of this example differs in that the first member  97   a  and the second member  96   a  have a hollow cylindrical shape accommodated in the toner accommodating portion ( 92  of  FIG. 5 ). In other words, the toner is accommodated inside the second member  96   a , so that an inner space of the second member  96   a  forms a toner accommodating portion  92   a  in which the toner is accommodated. By such a configuration, the length of the toner refill cartridge  9   a  may be shortened, so that the package size of the toner refill cartridge  9   a  distributed individually as a consumable may be reduced. Therefore, the packaging cost and logistics cost may be reduced. 
     A toner discharge port  94  is provided at an end portion  911  in the longitudinal direction A of the body  91   a . The toner discharge port  94  is communicated with the toner accommodating portion  92   a . The toner accommodating portion  92   a  is communicated with the outside through the toner discharge port  94 . A shutter  95  for selectively opening and closing the toner discharge port  94  may be provided at the end portion  911  of the body  91   a.    
     The first member  97   a  is rotatably supported by the body  91   a . A spiral portion  971  is provided in the longitudinal direction A in the first member  97   a . The first member  97   a  is inserted into the body  91   a  and is rotatably supported by the body  91 . The first member  97   a  may have a hollow cylindrical shape. The spiral portion  971  is provided on an inner wall of the first member  97   a . The spiral portion  971  extends in the longitudinal direction A. 
     The handle  98  is exposed to the outside of the body  91   a  to rotate the first member  97   a . The handle  98  is exposed to the outside of the body  91   a  through the end portion  912  of the body  91   a  for the user to hold by hand. The handle  98  may be integrally formed with the first member  97   a  or may be manufactured as a separate member and coupled to the first member  97   a.    
     The second member  96   a  is located inside the first member  97   a  and the second member  96   a  may accommodate toner. The second member  96   a  may have a hollow cylindrical shape. The inner space of the second member  96   a  forms the toner accommodating portion  92   a  in which toner may be accommodated. The second member  96   a  comprises a side wall  962  and a guide groove  961  extending in the longitudinal direction A through the side wall  962 . 
     The plunger  93   a  is inserted into the second member  96   a . The plunger  93   a  comprises a guide protrusion  933  which passes through the guide groove  961  and is engaged with the spiral portion  971 . The plunger  93   a  is moved in the longitudinal direction A as the first member  97   a  is rotated to push the toner inside the second member  96   a  toward the toner discharge port  94 . 
     In one example, the plunger  93   a  may include a moving member  934  provided with the guide protrusion  933  and a packing member  932  provided on the moving member  934  and in contact with the inner wall of the second member  96   a . The moving member  934  is inserted into the second member  96   a . The packing member  932  pushes the toner inside the second member  96   a  toward the toner discharge port  94  when the moving member  934  is moved in the longitudinal direction A toward the end portion  911 . The packing member  932  may be formed of an elastic material such as rubber or the like, which elastically contacts the inner wall of the second member  96   a.    
     As shown in  FIG. 7 , the plunger  93   a  may be inserted into the second member  96   a , the second member  96   a  may be inserted into the first member  97   a , and the first member  97   a  may be inserted into the body  91   a . The guide protrusion  933  penetrates through the side wall  962  of the second member  96   a  through the guide groove  961  to protrude from the side wall  962  and engages with the spiral portion  971 . The plunger  93   a  is located at the top dead position Q 1  inside the toner accommodating portion  92   a . The top dead position Q 1  is a position at which the packing member  932  is away from the toner discharge port  94 , that is, a position adjacent to the end portion  912 . 
     In this state, when the toner refill cartridge  9   a  is inserted into the communication portion  8  as shown in  FIG. 1 , the toner refill cartridge  9   a  is connected to the toner filling portion  10  as shown in  FIG. 3 . The handle  98  is exposed to the outside of the body  91   a  through the end portion  912  of the body  91   a . When the handle  98  is turned, the first member  97   a  is rotated. Thrust in the longitudinal direction A is applied to the guide protrusion  933  by the spiral portion  971 . Since the guide protrusion  933  is inserted into the guide groove  961  extending in the longitudinal direction A, the guide protrusion  933  is guided to the guide groove  961  and moved in the longitudinal direction A. The packing member  932  pushes toner contained in the second member  96   a  to the outside through the toner discharge port  94 . The toner discharged from the toner discharge port  94  may pass through the toner filling portion  10  and be accommodated in the toner accommodating portion  230  inside the developing cartridge  2 . When the packing member  932  reaches the bottom dead position Q 2  as shown in  FIG. 8 , toner filling is completed. 
     By such a configuration, a sudden movement of the plunger  93   a  and a sudden discharge of the toner may be prevented. In addition, the toner refill cartridge  9   a  of this example is shorter in length than the toner refill cartridge  9  shown in  FIGS. 4 to 6 . Accordingly, the packaging size of the toner refill cartridge  9   a  which is distributed individually as a consumable may be reduced, so that the packaging cost and the logistics cost may be reduced. 
       FIG. 9  is a perspective view of a toner refill cartridge showing a state in which an extension handle is located at a first position according to an example.  FIG. 10  is a perspective of a toner refill cartridge showing a state in which an extension handle is located at a second position according to an example. 
     Referring to  FIGS. 9 and 10 , the toner refill cartridge  9   b  differs in that an extension handle  99  is provided as compared with the toner refill cartridge  9  shown in  FIGS. 4 to 6  and the toner refill cartridge  9   a  shown in  FIGS. 7 and 8 . Therefore, hereinafter, a repetitive description will be omitted and the differences will be described. 
     Referring to  FIGS. 9 and 10 , the handle  98  has the extension handle  99  that may be switched to a first position (see  FIG. 9 ) folded in the handle  98  and a second position (see  FIG. 10 ) extending outward from the handle  98 . The extension handle  99  may be applied to the toner refill cartridge  9  and the toner refill cartridge  9   a . The extension handle  99  extends the area of the handle  98  to the outside of the handle  98  so that the user may hold the handle  98  and easily rotate the first members  97  and  97   a.    
     In one example, the extension handle  99  may be connected to the handle  98  to be rotated to the first and second positions. The extension handle  99  may have a rotating portion  991 . The rotating portion  991  may be rotatably connected to the handle  98  through a hinge  992 . The hinge  992  may be provided near the edge of the handle  98 . In the first position, the rotating portion  991  is folded to an upper surface of the handle  98 . Therefore, an increase in the size of the toner refill cartridge  9   b  due to the extension handle  99  may be minimized. 
     As shown in  FIG. 10 , in the second position, the rotating portion  991  is rotated about the hinge  992  and extends from the hinge  992  to the outside of the handle  98 . The edge of the handle  98  extends outward by the length of the rotating portion  991 . Accordingly, the user may hold the rotating portion  991  and easily rotate the handle  98 . 
     The extension handle  99  may further include an extension portion  993  extending in the longitudinal direction A from the rotating portion  991 . An end portion  994  of the rotating portion  991  opposite to the hinge  992  may extend beyond the edge of the handle  98 . The extension portion  993  may extend in the longitudinal direction A from the opposite end portion  994  of the rotating portion  991 . By such a configuration, as shown in  FIG. 9 , in the first position, the extension portion  993  does not interfere with the bodies  91  and  91   a . In the second position, as shown in  FIG. 10 , the rotating portion  991  is rotated about the hinge  992  and extends from the hinge  992  to the outside of the handle  98 , and the extension portion  993  extends in a direction opposite to the longitudinal direction A from the opposite end portion  994  of the rotating portion  991 . The user may hold the extension portion  993  and easily rotate the handle  98 . 
     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