JP2009025663A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developing device which does not cause deterioration of image quality resulting from selection of particle size and degradation of toner or the like and overfilling a toner supply part with toner, and provides high image quality in a developing device in an image forming apparatus such as a copying machine. <P>SOLUTION: As a member for partitioning the inside of the main body (50) of the developing device for developing a latent image formed on the outer circumferential surface of an image carrier to be a visible image with the toner to a toner storage part (55) storing the toner supplied from a toner replenishing port (51) and a toner supply part (56) having a developing roller (66) supplying the toner to the image carrier, a first partition member which rises from a bottom part on the toner storage part side and a second partition member which hangs from the ceiling part on a toner supply part side are provided, and the height of the upper end of the first partition member is set higher than the lower end of the second partition member, and also a space part (57) between both partition members is formed so that a part nearer to the toner replenishing port may be narrower and an opposite side thereto may be wider. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, and a facsimile, and more particularly to a developing device provided in the image forming apparatus.

  In an image forming apparatus such as a copying machine or a printer, a toner image is formed by a developing device including a photosensitive drum as an image carrier, and the toner image is transferred onto the surface of a sheet as a recording medium. The toner image is fixed on the paper by applying heat and pressure to the paper on which the toner image is formed by a fixing device.

  The toner for image formation is supplied into the main body from a replenishing port provided in the main body of the developing device, and is supplied to the photosensitive drum as the image carrier through the developing roller, and the charged portion on the surface of the photosensitive drum. A visible image is formed by adhering to the surface. The thickness of the toner layer adhering to the surface of the developing roller is regulated by a member for regulating the thickness that presses against the surface of the developing roller or faces the developing roller with a space therebetween. It is designed to be formed on the surface.

  By the way, in an apparatus that regulates the thickness of the toner layer formed on the developing roller with a regulating member, toner having a small particle size tends to adhere to the developing roller preferentially and toner having a large particle size tends to remain. . Also, when the toner remaining on the developing roller after development is removed, the toner tends to be removed from the toner having a large particle size preferentially. In the remaining toner, the ratio of the toner having a large particle diameter gradually increases, resulting in a problem that the image quality of the formed image is deteriorated.

In order to solve such a problem caused by the particle size selection action, as disclosed in Japanese Patent Application Laid-Open No. H10-228707, the developing device that accommodates the toner is divided into two, and the particle size separated from the developing roller is large. An apparatus that restricts the return of toner has been considered.
JP 2003-255687 A

  Among the devices described in Patent Document 1, the developing device according to the first invention is, as shown in FIG. 10, provided with a partition wall 101 in the developing device main body, and a toner storage portion 102 for storing toner. And a toner supply unit 103 that supplies toner to the toner carrier 107 that conveys toner to the image carrier (photosensitive drum), and an opening 104 is provided in the partition wall, and the toner is accommodated in the opening. This is provided with a backflow prevention valve structure provided with an opening / closing member 105 that opens the opening only when the toner is guided from the section to the toner supply section. A toner feeding member 106 that guides the toner to the toner supply unit through the opening 104 is provided in the toner storage unit 102, and the toner supply that supplies the toner in the toner supply unit 103 to the toner carrier (developing roller) 107. A member (roller) 108 is provided. The upper end of the opening / closing member 105 is fixed to the upper side of the opening, and a protrusion 109 protruding toward the toner supply unit is provided at the lower part of the opening / closing member 105 that is not fixed. 111 in the figure is a sealing material.

  According to this configuration, when toner is accumulated to some extent in the toner supply unit 103, the toner opens and closes the opening / closing member 105 toward the partition wall 101, and the toner in the toner storage unit 102 is transferred by the toner feeding member 106. Even when guided to the opening, since the opening 104 of the opening / closing member 105 is maintained in a closed state, the supply of toner to the toner supply unit 103 is restricted. For this reason, clogging of toner due to excessive supply is prevented, a large load is not applied to the toner supply member 108, and toner is stably supplied to the toner carrier 107.

  The developing device according to the second invention of Patent Document 1 is a developing device provided with a toner supply roller for supplying toner in the toner supply unit 102 to the toner carrier 107 in addition to the configuration described above. By setting the circumferential nip width at which the toner supply roller and the toner carrier 107 are in contact with each other within a predetermined range, the toner is circulated in the toner supply unit to prevent clogging of the toner and application of a large load. is there.

  Further, the developing device according to the third invention in Patent Document 1 promotes the circulation of the toner in the toner supply section by maintaining the nip width and other dimensions within a predetermined range, as in the second invention. To do.

  However, the apparatus described in Patent Document 1 has a backflow prevention valve structure in which an opening 104 is provided in a partition wall 101 that partitions the inside of the developing device, and the opening is opened only in a predetermined direction. When the amount of toner in the section 103 increases, the toner supply through the opening is restricted, so that the structure and operation of the opening / closing member 105 that opens and closes the opening 104 is complicated, and the maintenance is complicated. There is a point.

  In addition, since the backflow prevention valve is used, the toner continuously supplied from the toner storage unit 102 is supplied to the toner supply unit 103 particularly when the amount of toner consumption is small, such as when printing on a low-density print original for a long time. When the toner is filled, the toner pressure becomes high, and there is a possibility that the deterioration rate of the toner increases at an accelerated speed. Such progress of toner deterioration is a serious problem because it causes various image defects such as density reduction, image fogging and toner scattering.

  Further, the toner is rubbed by the regulating member 110 and the toner carrier 107 at a portion that regulates the toner layer thickness, and is charged and deteriorated. However, the development is attempted in order to achieve a longer life and a smaller size of the developing device. When the toner capacity of the apparatus is reduced, deteriorated toner is accumulated in the toner supply unit 103, and the ratio of deteriorated toner increases. For this reason, the longer the printing is performed, the larger the difference in toner deterioration level between the toner storage unit 102 and the toner supply unit 103, and the deterioration occurs when the toner is supplied from the toner storage unit 102 to the toner supply unit 103. There is also a case where charging failure occurs between the toner that has not been deteriorated and the toner that has deteriorated, and the deteriorated toner is charged to a reverse polarity. Thus, the deteriorated toner charged to the reverse polarity appears as a fog on the image.

  Therefore, in view of such problems of the conventional apparatus described above, the present invention does not cause a decrease in image quality due to particle size selection, toner deterioration, or the like, and does not cause overfilling of the toner supply unit. An object of the present invention is to provide an image forming apparatus equipped with a developing device that prevents deterioration in image quality and obtains a long life by making it difficult to cause poor mixing of new toner and toner in the developing device at the time. .

  In order to solve the above problems, the present invention employs the following configuration.

That is, the first aspect of the present invention is an image forming apparatus including a developing device that converts a latent image formed on the outer peripheral surface of an image carrier into a visible image with toner.
A partition member that divides the inside of the main body of the developing device into a toner accommodating portion that accommodates toner and a toner supply portion that includes a developing roller that supplies toner to the image carrier;
A toner replenishing port for replenishing toner from the outside to the toner container,
A first partition member that is positioned on the toner container side and stands up from a bottom of the toner container to a position that does not reach the ceiling; the partition member that partitions the inside of the main body of the developing device; A second partition member that is located closer to the toner supply unit than the first partition member and hangs from the ceiling to a position that does not reach the bottom;
In the image forming apparatus, an interval between the first partition member and the second partition member is formed so that the toner supply port side is narrow and a portion far from the toner supply port is wide.

  According to a second aspect of the present invention, the upper end portion of the first partition member is formed so that the toner replenishing port side is high and the side far from the toner replenishing port is low. Device.

  According to a third aspect of the present invention, the lower end portion of the second partition member is formed such that the toner supply port side is low and the side far from the toner supply port is high. This is an image forming apparatus.

  The present invention has an effect that it is possible to provide an image forming apparatus including a developing device that prevents deterioration in image quality and obtains a long life.

  Hereinafter, embodiments of the present invention will be specifically described. FIG. 1 illustrates a configuration of a printer as an example of an image forming apparatus including a developing device according to the present invention, and the image forming apparatus 1 stores a sheet P that is a recording medium for printing an image. A paper tray 2 and a manual tray (not shown) for manually feeding paper are provided. The paper P fed one by one from the paper tray 2 (or manual feed tray) by the feeding roller 4 is discharged from the image transfer unit 5 through the fixing unit 7 onto the discharge tray 8.

  The developing device 10 is formed as a rotary developing unit, and this rotary developing unit includes a rotating support 11 that rotates in a predetermined direction, and four sets of developing devices 15 are provided inside the rotating support 11. Yes. The four sets of developing devices 15 supply toner of four colors (yellow, cyan, magenta, black), and have a space for storing the toner, and a stirring device, a toner supply roller, and a developing roller, which will be described later, in the space. Is provided.

  A photosensitive drum 20 that is an image carrier is provided adjacent to the outer periphery of the rotary support 11. In the outer peripheral portion of the photosensitive drum 20, a rubbing member 21 that cleans toner remaining on the outer peripheral surface of the photosensitive drum 20, a cleaning member 22, and a charging member 23 that charges the surface of the photosensitive drum 20. The laser irradiator 24 is sequentially provided along the rotation direction.

  Reference numeral 25 in the figure denotes a laser scanning unit which emits a laser according to the obtained image data, and laser light is applied to the surface of the photosensitive drum 20 by the laser irradiation unit 24 through an optical path provided with a mirror 26 and the like. It comes to irradiate.

  The image forming apparatus 1 is provided with an intermediate transfer unit 30. The intermediate transfer unit 30 includes an intermediate transfer belt 32 that circulates in the direction of arrow Z in FIG. A driving roller 31, a driven roller 34, a first transfer roller 36, a tension roller 37, a second transfer roller 38, a cleaning device 35, and the like are provided along the movement path of the intermediate transfer belt 32.

  The developing device 10 is provided with a container 40 and a replenishment pipe 41 for feeding the toner in the container 40 to the developing device 15 as toner replenishing means for supplying toner to the developing device 15. The combination of the container 40 and the supply pipe 41 is provided side by side along the rear side direction in the drawing so as to correspond to each of the four developing devices 15 (only one set is shown in the drawing).

  The fixing unit 7 includes a heating roller 45 heated to a predetermined temperature, and a pressure roller 46 that presses the paper P against the heating roller 45. The paper P onto which the toner image has been transferred by the transfer unit 30 is heated to a predetermined temperature while passing between the heating roller 45 and the pressure roller 46, and is pressed and transferred to the surface. The image is fixed on the paper.

  Next, FIG. 2 is an enlarged view of the developing device 15 constituting the developing device (rotary developing unit) 10, and each developing device 15 has a space formed inside a main body 50 having a predetermined width. A toner replenishing port 51 is formed at an appropriate position in the width direction (direction perpendicular to the paper surface of the drawing) of the ceiling 50a of the main body. New toner is supplied from the supply port 51 into the main body. In the four developing units 15, the positions of the replenishing ports 51 in the width direction are shifted from each other so that the replenishing pipes for the developing units 15 do not interfere with each other.

  A space inside the main body 50 is divided into a toner storage portion 55 and a toner supply portion 56 by a first partition member 53 and a second partition member 54. The toner supply unit 56 has an opening 52 that communicates with the outside. The first partition member 53 is provided on the toner accommodating portion 55 side so as to rise from the bottom portion 50 b of the main body, a curved portion 53 a is formed at a lower portion thereof, and an upper end portion is a ceiling portion 50 a of the main body 50. It has reached a position close to.

  The second partition member 54 is provided on the toner supply unit 56 side with a certain distance d (d = 4 mm in the illustrated example) between the first partition member 53 and the second partition member 54 from the ceiling 50 a of the main body 50. It is formed in a hanging plate shape. The second partition member 54 is attached to an overhang portion 59 provided on the main body so as to protrude into the main body 50. In the illustrated example, the first partition member 53 and the second partition member 54 are formed of a SUS plate having a thickness of 0.5 mm.

  A gap 57 between the first partition member 53 and the second partition member 54 is a toner passage. And the position of the upper end part 53b of the 1st partition member 53 is higher than the position of the lower end part 54b of the 2nd partition member 54 so that it may mention later, and both partition members 53 and 54 are front view. It overlaps vertically (see FIGS. 4 and 7).

  A stirring member 60 is provided at a lower position of the toner container 55. The toner in the toner accommodating portion 55 is agitated and mixed by the rotation of the agitating member 60, and jumped up to the first partition member 53 side, so that it gets over the first partition member 53 and is on the toner supply portion 56 side. Sent to. As shown in FIG. 3, the stirring member 60 has one blade 62 made of a thin plate (a PET film having a thickness of 40 μm in the illustrated example) that can be elastically deformed attached to the rotating shaft 61. A plurality of parallelogram measuring windows 63 are formed on the plate surface of the blade 62 so as to communicate with the front and back sides. The window 63 may be rectangular or square. However, if the window 63 is formed in a parallelogram as shown in FIG. 3, the toner 63 receives a force for moving the toner in a predetermined direction (arrow side in the illustrated example) during stirring. Therefore, the shape may be obtained so that an optimum stirring state can be obtained according to the position of the replenishing port 51 to which new toner is supplied.

  The toner supply unit 56 is provided with a toner supply roller 65 and a developing roller 66 so as to be in close contact with each other. The contact nip between these rollers 65 and 66 is set to 3 mm. The toner supply roller 65 is a flexible roller, for example, a urethane sponge roller having a resistance value of 1E + 8Ω. The toner supply roller 65 is rotatably supported in a state where the toner supply roller 65 is partially fitted into the curved portion 53 a of the first partition member 53. The developing roller 66 is, for example, an elastic roller having a JIS-A hardness of 45 degrees, a resistance value of 1E + 6Ω, and a surface roughness Ra of 1.0 μm, and its outer peripheral surface partially protrudes outward from the opening 52 of the main body 50. . The toner supply roller 65 made of sponge is in a slightly depressed state in contact with the developing roller 66.

  A layer thickness regulating member 69 provided in the opening 52 is in sliding contact with the upper surface of the developing roller 66. The layer thickness regulating member 69 is for keeping the thickness of the toner layer adhering to the outer peripheral surface of the developing roller 66 constant. For example, a SUS foil having a thickness of 0.08 mm is used and the regulation pressure is set to 25 N / m. Has been. As a result, the toner layer thickness of the photosensitive drum 20 that is an image carrier is also regulated by the regulating member 69.

  A seal member 58 that seals the gap between the developing roller and the main body 50 is provided below the developing roller 66. The seal member 58 is formed of, for example, a conductive high molecular weight PE film, and is backed up with a urethane sponge so as to uniformly contact the developing roller 66.

  Next, an outline of the operation of the image forming apparatus 1 will be described. Laser light is emitted from the laser scanning unit 25 in accordance with the image data and irradiated onto the photosensitive drum 20 as an image carrier, and an electrostatic latent image is formed on the photosensitive drum 20. As the photosensitive drum 20 rotates, the outer peripheral surface becomes clean with the toner removed by the rubbing member 21, the cleaning member 22, etc., and is charged by the charging member 23. An image is formed.

  On the other hand, among the four developing devices 15 of the rotary developing unit 10, the developing device 15 that holds toner of a specific color faces the photosensitive drum 20 based on the electrostatic latent image, and the toner storage portion thereof. The toner is guided from 55 to the toner supply unit 56, supplied from the toner supply roller 65 to the developing roller 66, and then supplied to the surface of the photosensitive drum 20. At this time, as described above, the layer thickness regulating member 69 regulates the toner layer thickness to be constant.

  Since the toner supplied from the developing roller 66 adheres only to a portion of the surface of the photosensitive drum 20 that does not have the same level of charge as the toner, a toner image of that color is formed by the selected one color toner. .

  This toner image is transferred to the intermediate transfer belt 32 by the first transfer roller 36 in the transfer portion 33. Thereafter, the rotary support 11 of the rotary developing unit 10 rotates by a predetermined angle, and toner images are formed on the intermediate transfer belt 32 for other colors by the same procedure.

  Thereafter, the toner images on which the four colors on the intermediate transfer belt 32 are superimposed are collectively transferred onto the paper P fed out at a predetermined timing by the second transfer roller 38. The sheet onto which the toner image has been transferred is sent to the fixing unit 7 where the toner image is fixed and then discharged onto the discharge tray 8.

  Next, the developing device 10 according to the present invention will be described in detail.

  4 and 5 schematically show the positional relationship among the toner supply roller 65, the developing roller 66, the first partition member 53, the second partition member 54, and the like provided in the developing unit 15. As described above, the height of the upper end portion 53 b of the first partition member 53 is higher than the lower end portion 54 b of the second partition member 54. 4 is a schematic front view, and FIG. 5 is a schematic plan view, which is slightly different from the specific example shown in FIG. That is, in FIG. 2, the first and second partition members 53 and 54 overlap with the supply roller 65 in plan view, and both the rollers 65 and 66 are in close contact with each other. These are shown separated from each other.

  In this embodiment, the height of the upper end portion 53b of the first partition member 53 is substantially constant, and the height of the lower end portion 54b of the second partition member 54 hanging from the ceiling portion is also substantially constant. However, the lower end portion 54 b of the second partition member 54 is located below the upper end portion of the first partition member 53.

  Further, as shown in FIG. 5, the distance d between the first partition member 53 and the second partition member 54 is narrower on the side close to the supply port 51 in plan view (d1), and as the distance from the supply port 51 increases. It inclines so that it may become wide (d2). The toner t supplied from the toner supply port 51 to the toner container 55 is stirred by the stirring member 60 in the toner container 55, and the toner splashed up by the blades 62 of the stirring member 60 is as shown in FIG. The first partition member 53 and the second partition member 54 are passed over the first partition member 53 and moved to the toner supply unit 56. As described above, the first partition member 53 and the second partition member 53 in the interval portion 57 through which the toner passes are provided. The distance d from the partition member 54 is narrower on the side closer to the replenishing port 51, and becomes wider as the distance from the replenishing port increases. Therefore, a force for moving the toner from the side closer to the replenishing port 51 toward the far side acts. (See arrow in FIG. 5).

  For this reason, the toner that has passed through the first partition member 53 moves in a direction away from the replenishment port 51 as shown by the arrows in FIGS. 4 and 5 at the space 57 with the second partition member 54. As a result of this movement, the toner is supplied uniformly, and the movement promotes stirring of the new and old toners.

  Next, FIG. 6 shows a mode slightly different from the above, and in this embodiment, the spacing portion 57 between the first partition member 53 and the second partition member 54 is formed in a step shape in plan view. The width d1 on the side close to the replenishing port 51 is narrow, and the width d2 on the far part is wide. Also in this case, the amount of toner supplied from a portion far from the replenishing port 51 is larger than the amount of toner supplied from the vicinity of the replenishing port 51, and the interval closer to the replenishing port 51 is narrower. There is a tendency to move away from the supply port 51. For this reason, the toner supplied from the vicinity of the replenishing port 51 and the toner replenished from other parts are mixed, and the difference in deterioration level is reduced.

  7 to 9 show examples in which the height relationship between the first partition member 53 and the second partition member 54 is different. In the illustrated example of FIG. 7, the height of the second partition member 54 is substantially the same. Although it is constant, the height of the upper end portion 53 b of the first partition member 53 is inclined so that the side close to the supply port 51 is high and gradually decreases as the distance from the supply port 51 increases.

  For this reason, it is possible to prevent new toner supplied from the replenishing port 51 to the toner storage unit 55 from directly over the first partition member 53. Further, at a position away from the replenishing port 51, the height of the first partition member 53 is low, so that the agitated toner can easily get over (see the arrow in FIG. 7). For this reason, it is possible to prevent the newly-supplied new toner from entering the toner supply unit 56, and to easily supply the uniformly stirred toner to the toner supply unit 56, thereby suppressing a difference in toner deterioration level. is there.

  FIG. 8 shows an embodiment further different from the above. In this embodiment, the height of the first partition member 53 is constant, but the height of the lower end portion 54b of the second partition member 54 is replenishment. It is low near the mouth 51 and gradually increases as the distance from the supply port 51 increases. For this reason, the toner that has entered between the first partition member 53 and the second partition member 54 does not easily pass under the second partition member 54 in the vicinity of the supply port 51, and passes through as it moves away from the supply port 51. It becomes easy. Therefore, the toner supplied in the vicinity of the replenishing port 51 is prevented from immediately entering the toner supply unit 56, and the agitated and uniform toner is easily supplied to the toner supply unit 56. Is kept small.

  FIG. 9 shows an embodiment further different from the above. In this embodiment, the upper end portion 53b is inclined so that the first partition member 53 is high on the supply port 51 side and low on the opposite side, The lower end portion 54b of the partition member 54 is inclined so that the supply port 51 side is low and the opposite side is high. For this reason, the new toner supplied from the replenishing port 51 to the toner accommodating portion 55 is not only difficult to get over the first partition member 53, but even if it gets over this, it is difficult to pass under the second partition member 54. Become. Therefore, the uniformity of the toner supplied to the developing roller is further promoted.

  In the above example, the example in which the upper end portion of the first partition member 53 and the lower end portion of the second partition member 54 are inclined in one direction has been described. However, the supply port 51 is located at the end portion of the developing device 15. If it is provided closer to the center portion, the width of the gap portion 57 may be narrowed at the portion of the replenishing port 51, and both sides thereof should be wide.

  When the replenishing port 51 is provided near the center of the developing device 15, the replenished toner is provided on the blade 62 of the stirring member 60 so that the replenished toner moves toward the left and right sides of the replenishing port 51. What is necessary is just to make the shape of the parallelogram window which is left and right symmetrical with respect to the position where the supply port 51 is provided.

  Further, in the above description, the developing device for color printing having four developing devices 15 has been described as an example, but an excellent effect can be obtained by adopting a similar partition structure even in an image forming device for monochrome printing. Needless to say.

  As described above, the image forming apparatus according to the present invention includes, in the developing device, the first partition member that is on the toner storage unit side and rises from the bottom, and is closer to the toner supply unit side than the first partition member. And a second partition member that hangs down from the ceiling portion, and since the upper end portion of the first partition member is formed above the lower end portion of the second partition member, After the toner in the toner container has passed over the upper end of the first partition member, the toner flows down through the space between the first and second partition members, and passes under the second partition member. The toner is supplied to the toner supply unit.

  For this reason, toner is supplied to the toner supply unit only as much as the toner in the toner supply unit is consumed, so that it is prevented from being supplied more than necessary, and the toner pressure is also increased beyond a certain level. Therefore, even if the low density output is continued for a long time, the toner pressure of the toner supply unit is kept almost constant. Further, the distance between the first partition member and the second partition member is narrower toward the toner replenishing port and wider as it is farther from the toner replenishing port. The toner guided to the second partition member moves from the narrower one to the wider one, and mixing is promoted during the movement. For this reason, the toner replenished from the vicinity of the replenishing port is prevented from being immediately supplied to the developing roller, and problems such as density reduction, fogging, and toner scattering due to toner deterioration do not occur, and image defects can be avoided. .

  Further, like a rotary developing device for multi-color printing, a developing device that includes a plurality of developing devices supported by a rotatable support and moves each developing device to a developing position by the rotation of the supporting member and performs development. In the case of the apparatus, since the first and second partition members are present, when the developing device rotates, the toner in the toner supply unit is placed on the lower side of the second partition member and the first one according to the rotation position. When the agitating member rotates at the developing position little by little through the upper side of the partition member and the toner in the toner storage unit rotates above the first partition member and below the second partition member. Then, the toner is again fed into the toner supply unit little by little. For this reason, each time the developing device rotates, the toner is replaced little by little between the toner storage unit and the toner supply unit, and an increase in the difference in toner deterioration level between the two is suppressed. If the toner deterioration level difference between the toner storage unit and the toner supply unit becomes large, charging failure occurs between the toner that has not deteriorated and the toner that has deteriorated when supplied from the toner storage unit to the toner supply unit. However, since the toner is charged to a reverse polarity, the above-described deterioration level difference does not become so large in this developing device, so that such a problem can be effectively prevented.

  Further, by setting the height of the first partition member provided on the toner supply port side to an appropriate height, new toner supplied from the toner supply port can be immediately supplied to the toner supply unit side. Can be suppressed. For this reason, the new toner replenished from the replenishing port is sufficiently mixed by the agitating member, and problems such as image fogging can be prevented.

  The image forming apparatus according to the present invention can prevent deterioration of image quality and extend the life of the developing device, and can be effectively used as an image forming apparatus such as a copying machine, a facsimile machine, and a printer.

Sectional drawing showing the structure of the printer which is an example of the image forming apparatus of this invention Sectional drawing showing the structure of the developing device of this Embodiment Front view of the stirring member of the present embodiment Front view schematically showing the positional relationship of main parts in the developing device of the present embodiment. The top view which represents typically the positional relationship of the main part in the image development apparatus of this Embodiment. The top view which represents typically the example different from the structure shown in FIG. 5 of the image development apparatus of this Embodiment. Schematic front view showing an example further different from the developing device of the present embodiment Schematic front view showing another example different from the developing device of the present embodiment Schematic front view showing still another example different from the developing device of the present embodiment Cross-sectional view of a conventional developing device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Paper tray 5 Transfer part 7 Fixing part 10 Developing apparatus 15 Developer 50 Developer main body 51 Supply port 53 First partition member 54 Second partition member 55 Toner container 56 Toner supply part 57 Spacing part 60 Stirring member 65 Toner supply roller 66 Developing roller

Claims (3)

In an image forming apparatus including a developing device that converts a latent image formed on an outer peripheral surface of an image carrier into a visible image with toner,
A partition member that divides the inside of the main body of the developing device into a toner accommodating portion that accommodates toner and a toner supply portion that includes a developing roller that supplies toner to the image carrier;
A toner replenishing port for replenishing toner from the outside to the toner container,
A first partition member that is positioned on the toner container side and stands up from a bottom of the toner container to a position that does not reach the ceiling; the partition member that partitions the inside of the main body of the developing device; A second partition member that is located closer to the toner supply unit than the first partition member and hangs from the ceiling to a position that does not reach the bottom;
An image forming apparatus, wherein an interval between the first partition member and the second partition member is formed such that the toner supply port side is narrow and a portion far from the toner supply port is wide.   The image forming apparatus according to claim 1, wherein an upper end portion of the first partition member is formed so that the toner supply port side is high and the side far from the toner supply port is low.   The image forming apparatus according to claim 1, wherein a lower end portion of the second partition member is formed so that the toner supply port side is low and the side far from the toner supply port is high.

Images