JP5957548B2 - Developer container and image forming apparatus - Google Patents

Description

  The present invention relates to a developer container that contains toner and a carrier, and an image forming apparatus including the developer container.

  Conventionally, in an electrophotographic image forming apparatus, an electrostatic latent image formed on the surface of a photosensitive drum or the like is developed by a developing device. As a development method, a method using a one-component developer composed only of toner and a method using a two-component developer including toner and carrier are known.

  When a two-component developer is used, there is a problem that the life of the developing device is shortened because the carrier contained in the developer in the developing device deteriorates with time. In order to deal with such problems, a developer container that supplies toner to the developing device stores not only toner but also a carrier, and a new carrier is supplied from the developer container to the developing device as needed (so-called so-called). "Trickle development") is known (see, for example, Patent Documents 1 and 2). By adopting such trickle development, it is possible to suppress the deterioration of the carrier in the developing device over time and to extend the life of the developing device.

  By the way, when such trickle development is employed, the toner and carrier contained in the two-component developer supplied from the developer container to the developing device in order to prevent image density variation and improve the image quality. It is important to stabilize the ratio (mixing ratio) as much as possible. In this regard, for example, in the system in which the toner and the carrier are sequentially filled in the developer container, even if the toner and the carrier are agitated after the filling is completed, if the agitation is insufficient, the developer is developed from the developer container. There is a possibility that the ratio of the toner and the carrier contained in the two-component developer supplied to the apparatus becomes unstable. In addition, since the toner and the carrier are filled in the same space in the developer container, once the toner and the carrier are filled in the developer container, the toner and the carrier cannot be separated after that. It becomes difficult to readjust the carrier ratio.

  On the other hand, Patent Document 3 discloses a configuration in which a developer container (see “toner container 7”) is filled with a premix toner obtained by previously diffusing toner and a carrier. However, in this prior art, when the toner and the carrier are not uniformly diffused in the premix toner, the toner container and the carrier are sequentially filled from the developer container. There is a possibility that the ratio of the toner and the carrier contained in the two-component developer supplied to the developing device becomes unstable.

  On the other hand, Patent Document 4 discloses a configuration in which a separately provided toner container (see “toner cartridge 33”) and a carrier container (see “carrier cartridge 48”) are connected to a developing device by a tube. Yes. In this configuration, since the toner discharged from the toner container and the carrier discharged from the carrier container are mixed in the tube, the ratio of the toner and the carrier contained in the two-component developer supplied to the developing device Can be stabilized.

JP 2002-258538 A JP 2007-086093 A JP 2007-133057 A JP 2007-101598 A

  However, in the prior art described in Patent Document 4, since the toner container and the carrier container are separately provided, a driving source for rotating a rotating member (for example, a conveying screw or a stirring paddle) provided in the toner container is provided. In addition, a drive source for rotating the rotating member provided in the carrier container is required, resulting in an increase in manufacturing cost. In addition, since the toner container and the carrier container are provided separately, the user must separately attach and detach the toner container and the carrier container to the tube, increasing the user's workload.

  In view of the above circumstances, an object of the present invention is to stabilize the ratio of the toner and the carrier contained in the two-component developer discharged from the developer container without increasing the work load on the user.

  The developer container of the present invention is a developer container used in an image forming apparatus that performs development processing using a two-component developer including toner and a carrier, and includes a toner storage space that stores the toner, and the toner storage. A container body having a merging space communicating with the space; a carrier tank for housing the carrier and having a carrier housing space communicating with the merging space; and detachably attached to the container body; and the container body A main body-side transport member that transports the toner from the toner storage space to the merge space, and the main body-side transport member includes a portion that is stored in the toner storage space. And the other portion provided downstream of the one portion in the toner transport direction by the main body side transport member and accommodated in the merge space. Is conveyed to the toner conveyed from the accommodation space from said carrier housing space joins the carrier in the converging space, characterized in that it is discharged to the outside from the merging space.

  By adopting such a configuration, a certain amount of toner and carrier can be merged in the merge space and then discharged to the outside from the merge space. Therefore, the ratio of the toner and the carrier contained in the two-component developer discharged from the developer container can be stabilized, and accordingly, variation in image density can be prevented and high image quality can be achieved. .

  In addition, since the carrier tank is mounted on the container main body, it is not necessary to attach and detach the carrier tank and the container main body separately from the developing device or the like, and the work burden on the user can be reduced.

  Furthermore, since the carrier tank can be attached to and detached from the container body, if the type and amount of carrier to be filled in the carrier tank are changed depending on the model and application of the image forming apparatus, it can easily cope with variations in models and applications. It becomes possible to do.

  In addition, since the toner and the carrier are filled in separate spaces (toner accommodation space and carrier accommodation space) in the developer container, even after the toner and carrier are once filled in the developer container, as necessary. It becomes possible to readjust the ratio of the toner and the carrier.

  The developer container of the present invention is a developer container used in an image forming apparatus that performs development processing using a two-component developer including toner and a carrier, and has a box shape with an upper surface side opened. A container main body having therein a toner storage space for storing toner; a merge space communicating with the toner storage space; and a carrier storage space for accommodating the carrier and in communication with the merge space; A carrier tank detachably attached to the container body, the container main body having a developer discharge port on the lower side of the merge space, and the toner transported from the toner storage space and the carrier storage space. The carrier to be conveyed merges in the merge space, and is discharged from the merge space to the outside through the developer discharge port.

  The developer container is rotatably provided in the container main body, and a stirring member that stirs the toner stored in the toner storage space, and is rotatably provided in the carrier tank, from the carrier storage space to the merging space. A tank-side transport member that transports the carrier to the outside, and the tank-side transport member is disposed coaxially with the stirring member and is provided to be rotatable integrally with the stirring member. good.

  The image forming apparatus of the present invention includes any one of the developer containers described above.

  According to the present invention, it is possible to stabilize the ratio of the toner and the carrier contained in the two-component developer discharged from the developer container without increasing the work burden on the user.

1 is a schematic diagram illustrating an outline of a configuration of a color printer according to an embodiment of the present invention. In the color printer which concerns on one Embodiment of this invention, it is a perspective view from the front right which shows a developer container. In the color printer which concerns on one Embodiment of this invention, it is a rear view which shows a developer container. In the color printer which concerns on one Embodiment of this invention, it is a plane sectional view which shows a developer container. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is a perspective view which shows a carrier tank in the developer container of the color printer which concerns on one Embodiment of this invention. It is CC sectional drawing of FIG. 1 is an explanatory diagram illustrating a configuration of a developing device in a color printer according to an embodiment of the present invention. In the developing device of the color printer which concerns on one Embodiment of this invention, it is explanatory drawing which shows the structure of a developer accommodating part.

  First, the overall configuration of a color printer 1 as an image forming apparatus will be described with reference to FIG. FIG. 1 is a schematic diagram showing an outline of a configuration of a color printer according to an embodiment of the present invention.

  The color printer 1 includes a box-shaped printer main body 2. A paper feed cassette 3 that stores paper (not shown) is provided at a lower portion of the printer main body 2. A tray 4 is provided.

  An intermediate transfer belt 5 is installed between a plurality of rollers on the upper part of the printer body 2, and an exposure unit 10 composed of a laser scanning unit (LSU) is disposed below the intermediate transfer belt 5. . A plurality of image forming units 6 are provided below the intermediate transfer belt 5. Each image forming unit 6 is provided corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (K), for example. Each image forming unit 6 is rotatably provided with a photosensitive drum 7 as an image carrier. Around the photosensitive drum 7, a charger 8, a developing device 11, a primary transfer unit 12, and the like. The cleaning device 13 and the static eliminator 14 are arranged in the order of the primary transfer process. A developer container 15 is provided above each developing device 11.

  A paper transport path 20 is provided on one side of the printer main body 2 (on the right side in the drawing). A paper feed unit 21 is provided at the upstream end of the conveyance path 20, and a secondary transfer unit 22 is provided at the other end (right end in the drawing) of the intermediate transfer belt 5 at a middle portion of the conveyance path 20. A fixing unit 23 is provided on the downstream side, and a paper discharge port 24 is provided on the downstream end of the transport path 20.

  Next, an image forming operation of the color printer 1 having such a configuration will be described.

  When the color printer 1 is turned on, various parameters are initialized, and initial settings such as temperature setting of the fixing unit 23 are executed. When image data is input from a computer or the like connected to the color printer 1 and an instruction to start printing is given, an image forming operation is executed as follows.

  First, after the surface of the photosensitive drum 7 is charged by the charger 8, the photosensitive drum 7 is exposed according to the image data by the laser light (see arrow P) from the exposure device 10, and the photosensitive member is exposed. An electrostatic latent image is formed on the surface of the drum 7. Next, the developing device 11 develops the electrostatic latent image into a toner image of a corresponding color with toner. This toner image is primarily transferred to the surface of the intermediate transfer belt 5 at the primary transfer portion 12. Each image forming unit 6 sequentially repeats the above operation, whereby a full-color toner image is formed on the intermediate transfer belt 5. The toner and electric charge remaining on the photosensitive drum 7 are removed by the cleaning device 13 and the static eliminator 14.

  On the other hand, the paper taken out from the paper feed cassette 3 or the hand tray (not shown) by the paper feed unit 21 is conveyed to the secondary transfer unit 22 in synchronism with the above-described image forming operation, and is subjected to secondary transfer. In the portion 22, the full color toner image on the intermediate transfer belt 5 is secondarily transferred to the paper. The sheet on which the toner image is secondarily transferred is conveyed downstream in the conveyance path 20 and enters the fixing unit 23 where the toner image is fixed on the sheet. The sheet on which the toner image is fixed is discharged from the sheet discharge outlet 24 to the sheet discharge tray 4.

  Next, the developer container 15 will be described with reference to FIGS. An arrow Fr appropriately attached to each figure after FIG. 2 indicates the front side of the developer container 15.

  The developer container 15 is detachably attached to the printer main body 2. As shown in FIG. 2, the developer container 15 includes a container body 26, a lid body 27 that covers the upper surface of the container body 26, a cover 28 that is attached to the front end of the container body 26, and a right side of the container body 26. And a carrier tank 29 detachably attached to the front end portion. Hereinafter, these will be described in order.

  First, the container body 26 and members provided on the container body 26 will be described. The container body 26 has a long shape in the front-rear direction. The container body 26 has a box shape with an upper surface opened. A main body side flange portion 31 is provided on the outer periphery of the upper end of the container main body 26. A toner filling port 33 is provided on the right side of the front end wall 32 of the container body 26. The toner filling port 33 is closed by a toner cap 34.

  As shown in FIG. 3, a driven coupling 36 is rotatably provided at the lower right portion of the rear end wall 35 of the container body 26 (lower left portion in the drawing of FIG. 3). An idle gear 37 that meshes with the driven coupling 36 is rotatably provided on the right side (the left side in the drawing) of the rear end wall 35 of the container body 26. The rear end wall 35 of the container body 26 is covered with a gear cover 38 (only a part is shown in FIG. 3).

  As shown in FIG. 4, a mounting recess 40 is formed at the right front end of the container body 26 across the front end wall 32 and the right side wall 39. The mounting recess 40 has a side surface portion 41 bent rearward from the right side portion of the front end wall 32 of the container main body 26, and a right side wall 39 of the container main body 26 bent rightward from the rear end of the side surface portion 41. And a rear surface portion 42 connected to the. A communication hole 43 is formed in the rear surface portion 42 in the front-rear direction.

  A toner storage space 44 is formed inside the container body 26, and toner such as magnetic toner is stored in the toner storage space 44. As shown in FIGS. 5 and 6, a merging space 45 is formed in the container body 26 at the lower right of the front end portion of the toner accommodating space 44. The rear side and upper left side of the merge space 45 communicate with the toner storage space 44. A developer discharge port 46 is formed in the container body 26 below the joining space 45. The lower side of the developer discharge port 46 is covered with a slidable shutter 47 so as to be opened and closed. When the developer container 15 is attached to the printer main body 2, the shutter 47 opens the developer discharge port 46. Has been. A carrier inlet 48 is formed in the container body 26 on the upper right side of the merge space 45. The carrier introduction port 48 is disposed behind the developer discharge port 46 and is provided close to the developer discharge port 46.

  As shown in FIG. 4, a first agitation paddle 50 is rotatably provided in the container body 26. The first agitation paddle 50 is accommodated in a portion extending from the left end portion to the right side portion of the toner accommodation space 44 and has a long shape in the front-rear direction. The first stirring paddle 50 includes a support frame 51 extending in the front-rear direction, and a stirring blade 52 attached to the support frame 51. The front end portion of the support frame 51 is pivotally supported on the front end wall 32 of the container body 26. The rear end portion of the support frame 51 passes through the rear end wall 35 of the container body 26 and protrudes to the rear side (outside) of the rear end wall 35 of the container body 26. The protruding portion includes a first stirring gear. 53 is provided. The first stirring gear 53 meshes with the driven coupling 36 (see FIG. 3).

  As shown in FIG. 4, a second stirring paddle 54 as a stirring member is rotatably provided on the container body 26 on the right side of the first stirring paddle 50. The second stirring paddle 54 is housed in the right end portion of the toner housing space 44 and has a shape that is long in the front-rear direction. The second stirring paddle 54 includes a shaft portion 55 extending in the front-rear direction, and a stirring portion 56 (see FIG. 5) attached to the shaft portion 55.

  As shown in FIG. 4, the front end portion of the shaft portion 55 projects through the communication hole 43 provided in the rear surface portion 42 of the mounting recess 40 of the container body 26 and protrudes to the front side (outside) of the rear surface portion 42. The projecting portion is provided with a main body side joint portion 57. The main body side joint portion 57 is exposed to the outside of the container main body 26. The rear end portion of the shaft portion 55 penetrates the rear end wall 35 of the container main body 26 and protrudes to the rear side (outside) of the rear end wall 35 of the container main body 26. The protruding portion includes a second stirring gear. 58 is provided. The second agitation gear 58 meshes with the idle gear 37 (see FIG. 3).

  As shown in FIGS. 4 and 6, the container body 26 is positioned between the first stirring paddle 50 and the second stirring paddle 54 and at a position lower than the first stirring paddle 50 and the second stirring paddle 54. In addition, a main body side conveying screw 60 as a main body side conveying member is rotatably provided. A portion extending from the front part to the rear part of the main body side conveying screw 60 is accommodated in the toner accommodating space 44 of the container main body 26. The front end portion of the main body side conveying screw 60 is accommodated in the merge space 45 of the container main body 26.

  The main body side conveying screw 60 includes a screw shaft 61 extending in the front-rear direction and a spiral fin 62 provided around the screw shaft 61. The front end portion of the screw shaft 61 is pivotally supported by a bearing portion 63 (see FIG. 2) provided at the lower right of the front end wall 32 of the container body 26. The rear end portion of the screw shaft 61 penetrates the rear end wall 35 of the container body 26 and protrudes to the rear side (outside) of the rear end wall 35 of the container body 26. Is provided. The transport gear 64 meshes with the driven coupling 36 (see FIG. 3).

  Next, the lid 27 will be described. As shown in FIG. 2, the lid 27 has a shape that is long in the front-rear direction. A lid body side flange portion 65 having a shape corresponding to the body side flange portion 31 of the container body 26 is provided at the lower end of the lid body 27, and the body side flange portion 31 and the lid body side flange portion 65 are ultrasonically welded. Thus, the container body 26 and the lid body 27 are integrated.

  Next, the cover 28 will be described. The cover 28 includes a front plate 66 that covers the front end wall 32 of the container body 26 and a side plate 67 that is bent rearward from the front plate 66. An engagement groove 68 (see FIG. 5) is formed in the upper portion of the left surface (inner surface) of the side plate 67.

  Next, the carrier tank 29 will be described. As shown in FIG. 4, the carrier tank 29 is inserted into the mounting recess 40 of the container body 26. The carrier tank 29 is held so as to be sandwiched between the side surface portion 41 of the mounting recess 40 of the container body 26 and the side surface plate 67 of the cover 28.

  As shown in FIG. 7, the carrier tank 29 has a flat shape that is long in the front-rear direction and the up-down direction. An engaging protrusion 70 is projected from the front upper portion of the right side surface of the carrier tank 29. A cylindrical fixed cylinder 71 projects from the lower end of the front surface of the carrier tank 29. The front end portion of the fixed cylinder portion 71 is closed with a cap 72. An insertion hole 74 (see FIG. 4) is provided on the rear surface of the carrier tank 29.

  As shown in FIG. 6, a carrier accommodating space 75 for accommodating a carrier is formed inside the carrier tank 29. The carrier filling amount in the carrier containing space 75 is, for example, 3 to 10% of the toner filling amount in the toner containing space 44 and is smaller than the toner filling amount in the toner containing space 44. Therefore, the volume of the carrier storage space 75 is smaller than the volume of the toner storage space 44. The ratio of the carrier filling amount in the carrier containing space 75 to the toner filling amount in the toner containing space 44 is, for example, 6% for a high speed machine (higher machine) and 3% for a low speed machine (lower machine). It can be changed as appropriate. Further, the type of carrier accommodated in the carrier accommodating space 75 can be changed as appropriate for each model.

  A carrier outlet port 73 is provided on the lower left side of the rear portion of the carrier tank 29, and the carrier accommodating space 75 and the joining space of the container body 26 are connected via the carrier outlet port 73 and the carrier inlet port 48 of the container body 26. 45 communicates.

  A tank-side conveying screw 76 as a tank-side conveying member is rotatably provided at the lower end portion of the carrier tank 29. As shown in FIG. 8, the tank-side conveying screw 76 includes a rotating shaft 77, a porous body 78 provided around the rear end portion of the rotating shaft 77, and a portion extending from the front end portion to the rear portion of the rotating shaft 77. And fins 79 that are provided around.

  The rotation shaft 77 extends in the front-rear direction. The front end portion of the rotation shaft 77 is pivotally supported by a cap 72 that closes the fixed cylinder portion 71 of the carrier tank 29. As shown in FIG. 4, the rear end portion of the rotating shaft 77 passes through the insertion hole 74 of the carrier tank 29 and protrudes rearward of the rear surface of the carrier tank 29. Is provided. The tank side joint portion 80 is exposed to the outside of the carrier tank 29. The tank side joint portion 80 is connected to a main body side joint portion 57 provided on the second stirring paddle 54.

  The porous body 78 is made of, for example, a sponge. As shown in FIG. 6 and the like, the porous body 78 has a cylindrical shape. The porous body 78 covers the carrier outlet 73 provided in the carrier tank 29.

  Next, the configuration of the developing device 11 will be described with reference to FIGS. 9 and 10.

  The developing device 11 includes a box-shaped casing 81. Inside the casing 81, a two-component developer containing toner and a carrier is accommodated. The casing 81 has a long shape in the front-rear direction (the depth direction in FIG. 9). A developer accommodating portion 82 is formed in the lower portion of the casing 81.

  A substantially U-shaped partition wall 83 is provided at the center of the developer accommodating portion 82. A first screw 84, a second screw 85, and a third screw 86 are rotatably provided on the left side, the right side, and the upper side of the partition wall 83, respectively. The developer is circulated. In the developer accommodating portion 82, toner concentration detecting means (not shown) for detecting the toner concentration in the developer is provided.

  As shown in FIG. 10, the developer accommodating portion 82 is provided with a developer replenishing port 87 at one end in the longitudinal direction of the portion where the first screw 84 is accommodated. The two-component developer supplied from the developer container 15 can be introduced into the developer container 82 through the developer supply port 87. The developer accommodating portion 82 is provided with an excess developer discharge port 88 on one end side in the longitudinal direction of the portion where the second screw 85 is accommodated. The overflowed developer can be discharged from the developer accommodating portion 82 through the excess developer discharge port 88.

  As shown in FIG. 9, a magnetic roller 90 is rotatably accommodated in the central portion of the casing 81 in the vertical direction. The magnetic roller 90 is disposed at the upper left of the second screw 85, and the two-component developer is supplied from the second screw 85 to the magnetic roller 90.

  A developing roller 91 as a toner carrier is rotatably accommodated in the upper part of the casing 81. The developing roller 91 is disposed on the upper right side of the magnetic roller 90 and faces the magnetic roller 90 with a predetermined interval. The toner in the two-component developer is supplied from the magnetic roller 90 to the developing roller 91. The developing roller 91 is in contact with or close to the photosensitive drum 7, and the toner in the two-component developer is supplied from the developing roller 91 to the photosensitive drum 7, so The electrostatic latent image is developed. As described above, the developing device 11 according to the present embodiment performs development processing using the two-component developer.

  In the developer container 15 configured as described above, in order to mount the carrier tank 29 on the container body 26, the carrier tank 29 is inserted into the mounting recess 40 of the container body 26. Then, the cover 28 is attached to the front end portion of the container body 26 while engaging the engagement groove 68 (see FIG. 5) of the cover 28 with the engagement protrusion 70 (see FIG. 7) of the carrier tank 29. Accordingly, the carrier tank 29 is held so as to be sandwiched between the side surface portion 41 of the mounting recess 40 of the container body 26 and the side surface plate 67 of the cover 28 (see FIG. 4). In this embodiment, the carrier tank 29 can be attached to the container body 26 using a simple configuration as described above. In order to remove the carrier tank 29 from the container body 26, the carrier tank 29 may be taken out from the mounting recess 40 of the container body 26 after removing the cover 28.

  When the carrier tank 29 is attached to the container main body 26 as described above, the main body side joint portion 57 provided in the second stirring paddle 54 and the tank side joint portion 80 provided in the tank side conveyance screw 76 are connected, The tank-side conveying screw 76 can rotate integrally with the second stirring paddle 54.

  In order to supply the two-component developer from the developer container 15 configured as described above to the developing device 11, the developer container 15 is attached to the printer main body 2. Accordingly, the driven coupling 36 (see FIG. 3) of the developer container 15 is connected to a drive coupling (not shown) provided in the printer main body 2. In this state, when a drive source (not shown) such as a motor connected to the drive coupling is rotated, this rotation is transmitted to the driven coupling 36 via the drive coupling, and the driven coupling 36 is unidirectional. (Clockwise in rear view, see FIG. 3). When the driven coupling 36 rotates in one direction as described above, the idle gear 37, the first agitation gear 53, and the transport gear 64 that mesh with the driven coupling 36 are moved in the other direction (counterclockwise in a rear view, see FIG. 3). Rotate. Further, the second stirring gear 58 meshing with the idle gear 37 rotates in one direction.

  When the first stirring gear 53 rotates in the other direction as described above, the first stirring paddle 50 rotates in the other direction. When the second stirring gear 58 rotates in one direction as described above, the second stirring paddle 54 rotates in one direction. When the first agitation paddle 50 and the second agitation paddle 54 rotate in this manner, the toner accommodated in the toner accommodating space 44 of the container main body 26 is agitated toward the main body side conveying screw 60 side. Be transported.

  Further, when the transport gear 64 rotates in the other direction as described above, the main body-side transport screw 60 rotates in the other direction. Accordingly, the toner stored in the toner storage space 44 is conveyed from the toner storage space 44 to the merge space 45. At this time, the toner conveyance direction by the main body side conveyance screw 60 is a direction from the rear side toward the front side (see an arrow X in FIG. 5).

  In addition, when the second stirring paddle 54 rotates in one direction as described above, the tank-side transport screw 76 connected to the second stirring paddle 54 rotates. When the tank-side conveyance screw 76 rotates in this way, the carrier in the carrier tank 29 is conveyed from the front side to the rear side by the fins 79 of the tank-side conveyance screw 76 and is held by the porous body 78 of the tank-side conveyance screw 76. The The carrier thus held in the porous body 78 is led out from the carrier outlet 73 as the tank-side transport screw 76 rotates, and is introduced into the merge space 45 through the carrier inlet 48.

  The carrier conveyed from the carrier accommodation space 75 to the merge space 45 by the tank-side conveyance screw 76 as described above is merged with the toner conveyed from the toner accommodation space 44 to the merge space 45 by the main body-side conveyance screw 60. At 45, merge and mix. As a result, a two-component developer including toner and carrier is formed. The two-component developer is discharged from the developer discharge port 46 to the outside of the developer container 15 by the main body side conveyance screw 60. The two-component developer discharged from the developer discharge port 46 in this way is introduced into the developer accommodating portion 82 of the developing device 11 through the developer supply port 87.

  In the developer container 15 of the present embodiment, as described above, the toner conveyed from the toner accommodating space 44 and the carrier conveyed from the carrier accommodating space 75 merge in the merging space 45 and are discharged from the merging space 45 to the outside. Yes. Therefore, after a certain amount of toner and carrier are merged in the merge space 45, they can be discharged to the outside from the merge space 45, and the ratio of toner and carrier in the two-component developer discharged from the developer container 15 can be determined. It can be stabilized. Along with this, variation in image density can be prevented and high image quality can be achieved.

  Further, since the carrier tank 29 is mounted on the container main body 26, it is not necessary to attach and detach the carrier tank 29 and the container main body 26 separately from the developing device 11 and the like, and the work burden on the user can be reduced.

  Furthermore, since the carrier tank 29 can be attached to and detached from the container body 26, if the type and amount of the carrier filled in the carrier tank 29 are changed according to the model and use of the color printer 1, the model and use can be varied. It becomes possible to cope easily. For example, in the case of a model that requires a long service life such as a high-speed machine, the amount of carriers in the carrier tank 29 is increased, and in the case of a model that requires a large cost reduction such as a low-speed machine, the carrier in the carrier tank 29 Reduce the amount. As a result, it is possible to deal with both models with a large demand for long life and models with a large demand for cost reduction by changing the specifications of the carrier tank 29, so that the container body 26 can be shared.

  Further, by making the carrier tank 29 and the container main body 26 detachable, the developer container 15 can be easily managed and the container main body 26 and the carrier tank 29 can be recycled separately.

  Further, since the toner and the carrier are filled in separate spaces (toner accommodation space 44 and carrier accommodation space 75) in the developer container 15, even after the toner container and the carrier are once filled in the developer container 15, If necessary, it is possible to readjust the ratio of toner and carrier.

  The container main body 26 and the carrier tank 29 are provided with a main body side transfer screw 60 and a tank side transfer screw 76, respectively. Therefore, the toner accommodated in the toner accommodating space 44 and the carrier accommodated in the carrier accommodating space 75 can be reliably conveyed to the merge space 45, and the toner and carrier merged in the merge space 45 can be merged. The space 45 can be reliably discharged.

  Further, when the carrier tank 29 is attached to the container body 26, the body side joint portion 57 and the tank side joint portion 80 are connected, and the tank side conveying screw 76 can be rotated integrally with the second stirring paddle 54. Has been. Therefore, the tank-side conveyance screw 76 can be rotated by a drive source for rotating the second stirring paddle 54 without providing a dedicated drive source for rotating the tank-side conveyance screw 76. Along with this, the manufacturing cost can be reduced.

  In the present embodiment, in particular, all the rotating members (the first stirring paddle 50, the second stirring paddle 54, the main body side conveying screw 60, and the tank side conveying screw) provided in the container main body 26 and the carrier tank 29 by a single driving source. 76) are simultaneously rotated. Therefore, further cost reduction can be achieved.

  Further, the carrier introduction port 48 is disposed on the upstream side of the developer discharge port 46 in the toner conveyance direction by the main body side conveyance screw 60 (in this embodiment, the direction from the rear side to the front side, see arrow X in FIG. 5). In addition, it is provided close to the developer discharge port 46. By adopting such a configuration, the carrier can be merged with the toner immediately before the two-component developer is discharged from the developer discharge port 46. As a result, the ratio of the toner and the carrier contained in the two-component developer discharged from the developer container 15 can be further stabilized.

  Further, when the tank-side conveying screw 76 rotates, the carrier held by the porous body 78 is led out from the carrier outlet port 73. By adopting such a configuration, the carriers accommodated in the carrier accommodating space 75 can be derived from the carrier outlet 73 little by little. For this reason, it is possible to avoid the disadvantage that the carrier in the carrier accommodation space 75 disappears even though the toner remains in the toner accommodation space 44 sufficiently.

  In the present embodiment, the case where the tank side conveyance screw 76 is connected to the second agitation paddle 54 provided in the container main body 26 has been described. However, in another different embodiment, the first agitation paddle 50 and the main body side conveyance screw 60 are connected. A tank-side conveying screw 76 may be connected to the tank. Also in this case, the number of driving sources can be reduced to reduce the cost.

  In the present embodiment, the case where the carrier introduction port 48 is arranged on the upstream side of the developer discharge port 46 in the toner conveyance direction by the main body side conveyance screw 60 has been described. It is not limited to. For example, in another different embodiment, a carrier introduction port 48 may be provided immediately above the developer discharge port 46.

  In the present embodiment, the case where two stirring members are provided in the container body 26 has been described (see “first stirring paddle 50” and “second stirring paddle 54”). On the other hand, in another different embodiment, the container main body 26 may be provided with one or a plurality of stirring members. In still another different embodiment, the container body 26 may not be provided with a stirring member.

  In this embodiment, the case where the configuration of the present invention is applied to the color printer 1 has been described. However, in other different embodiments, the present invention is applied to other image forming apparatuses such as a monochrome printer, a copier, a facsimile machine, and a multifunction machine. A configuration may be applied.

1 Color printer (image forming device)
DESCRIPTION OF SYMBOLS 15 Developer container 26 Container main body 29 Carrier tank 44 Toner storage space 45 Merge space 46 Developer discharge port 54 2nd stirring paddle (stirring member)
60 Main body side conveying screw (Main body side conveying member)
75 Carrier accommodating space 76 Tank side transfer screw (tank side transfer member)

Claims (4)

A developer container used in an image forming apparatus that performs development processing using a two-component developer containing toner and a carrier,
A container body having a toner storage space for storing the toner, and a merge space communicating with the toner storage space;
A carrier tank that houses the carrier and has a carrier housing space that communicates with the merge space, and is detachably attached to the container body;
A main body side conveying member that is rotatably provided in the container main body and conveys the toner from the toner accommodating space to the merge space;
A tank-side conveyance member that is rotatably provided in the carrier tank and conveys the carrier from the carrier accommodation space to the merge space ,
The container body has a developer outlet on the lower side of the merge space,
A mounting recess into which the carrier tank can be inserted is provided on the side wall of the container body,
The container body and the carrier tank have a long shape in the front-rear direction,
The main body side conveying member has a screw shaft extending linearly in the front-rear direction,
The tank side conveying member has a rotation shaft extending linearly in the front-rear direction, and the rotation shaft is provided above the screw shaft,
The main body side conveying member is provided downstream of the one portion accommodated in the toner accommodating space and in the toner conveying direction by the main body side conveying member, and accommodated in the merge space. And having other parts
The toner conveyed from the toner accommodating space to the merging space by the one portion of the main body side conveying member and the carrier conveyed from the carrier accommodating space to the merging space by the tank side conveying member are A developer container, which merges in a merge space and is discharged to the outside through the developer discharge port from the merge space by the other portion of the main body side conveying member . The container body is a box shape whose upper surface side is opened, and the toner accommodating space, the developer container according to claim 1, characterized in that a said converging space, the inside. Rotatably provided in the container main body, further comprising a stirring member for stirring the toner accommodated in the toner accommodating space,
3. The developer container according to claim 1, wherein the tank-side transport member is disposed coaxially with the agitation member and is rotatably provided integrally with the agitation member.   An image forming apparatus comprising the developer container according to claim 1.

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