JP2014178543A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device in which a developer held by the brush layer of a brush roller can be more excellently scraped by a scraping member.SOLUTION: The developing device includes a housing 100 including a supply part 121 which can store toner T (developer), a brush roller 11 including a roller body 11A and a brush layer 11B formed by planting fibers on the outer peripheral surface of the roller body 11A and supported by the housing 100, so as to come into contact with the toner T in the supply part 121, and a blade 12 (scraping member) configured so as to come into contact with the brush roller 11 above a position where the brush roller 11 faces the toner T in the supply part 121 and so as to scrape the toner T held by the brush layer 11B. The housing 100 includes a partition 106 which is arranged to face the brush roller 11 below the position where the blade 12 comes into contact with the brush roller 11 and can suppress the level of the toner T in the vicinity of the brush roller 11 in the supply part 121.

Description

  The present invention relates to a developing device including a brush roller.

  2. Description of the Related Art Conventionally, a developing device provided in an electrophotographic image forming apparatus is known to contain a developer and supply the developer to a photoreceptor by a brush roller (for example, a patent) Reference 1).

  The developing device includes a supply unit for supplying the developer to the brush roller, and a scraping member that scrapes off the developer held on the brush layer of the brush roller supplied by the supply unit above the supply unit. ing.

JP-A-57-109965

  However, in the above-described technique, when the developer level in the supply unit becomes high and the developer contacts excessively, such as the position where the scraping member contacts the brush roller is filled with the developer, the scraping member Therefore, the developer held on the brush layer may not be sufficiently scraped off.

  Accordingly, an object of the present invention is to provide a developing device that can favorably scrape off the developer held on the brush layer of the brush roller by a scraping member.

In order to achieve the above-described object, the developing device of the present invention includes a housing having a supply section capable of storing a developer, a roller body, and a brush layer in which fibers are implanted on the outer peripheral surface of the roller body. A brush roller supported by the housing so as to be in contact with the developer in the supply unit, and the brush roller is in contact with the brush roller above a position where the brush roller faces the developer in the supply unit, and the brush layer A scraping member configured to scrape off the developer held on the head.
And the housing | casing is arrange | positioned facing the brush roller below the position where a scraping member contacts a brush roller, and has a wall which can suppress the water level of the developer in the brush roller vicinity in a supply part. .

  Here, the water level of the developer is the height position of the upper surface of the developer stored in the supply unit.

  According to the developing device configured as described above, the position where the scraping member contacts the brush roller is filled with the developer, or the developer is excessively placed on the brush roller at the position where the scraping member contacts. Can be suppressed. Thereby, the developer held by the brush layer by the scraping member can be scraped well.

  In the developing device described above, it is desirable that the wall be close to the brush roller with a gap between the wall and the brush layer.

  According to the developing device configured as described above, when the developer is excessively loaded on the brush roller, the excessive developer contacts the wall and falls from the brush roller. Therefore, before the scraping member contacts, The developer on the brush roller can be reduced to some extent. Thereby, the developer held by the brush layer by the scraping member can be scraped well.

  In the developing device described above, it is preferable that the housing has a return path configured to return the developer scraped by the scraping member to the supply unit.

  According to the developing device configured as described above, the developer scraped by the scraping member can be reduced from staying in the vicinity of the brush roller.

  In the developing device having the return path described above, the housing includes a developer storage section that can store the developer supplied to the supply section, and the return path passes through the developer storage section. desirable.

  According to the developing device configured as described above, the developer can be circulated in the housing, and the developer scraped off by the scraping member can be mixed with the developer in the developer accommodating portion.

  Further, the developing device having the return path passing through the developer accommodating portion described above includes a return transport member that is provided in the vicinity of the scraping member and transports the developer scraped by the scraping member toward the return path. It is desirable that

  According to the developing device configured as described above, the developer scraped by the scraping member can easily move toward the return path.

  In the developing device described above, it is desirable that the supply unit is provided with a stirring member configured to stir the developer in the supply unit.

  According to the developing device configured as described above, it is possible to suppress the uneven supply of the developer to the brush roller.

  According to the present invention, the position where the scraping member contacts the brush roller is filled with the developer, and the developer is prevented from being excessively placed on the brush roller at the position where the scraping member contacts. be able to. Thereby, the developer held by the brush layer by the scraping member can be scraped well.

1 is a diagram illustrating a schematic configuration of a laser printer including a developing cartridge according to a first embodiment of the present invention. FIG. 3 is a cross-sectional view showing a developing cartridge. It is II sectional drawing (a) in FIG. 2, and II-II sectional drawing (b). FIG. 10 is a cross-sectional view showing a return path of a developing cartridge according to a first modification of the first embodiment. FIG. 4A is a cross-sectional view showing a developing cartridge according to a second modification of the first embodiment, and FIG. 4B is a cross-sectional view taken along line III-III in FIG. 4A is a cross-sectional view showing a developing cartridge according to a second embodiment, and FIG. 4B is a cross-sectional view taken along line IV-IV in FIG.

[First Embodiment]
Next, a first embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the following description, after describing the schematic configuration of the laser printer 1 to which the developing cartridge 7 as an example of the developing device according to the embodiment is attached and detached, the detailed configuration of the developing cartridge 7 according to the characteristic part of the present invention explain.

  In the following description, the direction will be described with reference to the user who uses the laser printer 1. That is, the right side in FIG. 1 is “front”, the left side is “rear”, the front side is “left”, and the back side is “right”. Also, the vertical direction in FIG.

<Schematic configuration of laser printer>
As shown in FIG. 1, a laser printer 1 includes a paper feed unit 3 that supplies paper S, an exposure device 4, a process cartridge 5 that transfers a toner image onto the paper S, and a paper S in a main body casing 2. The image forming apparatus mainly includes a fixing device 8 that thermally fixes the upper toner image.

  The paper feed unit 3 is provided at a lower portion in the main body casing 2 and mainly includes a paper feed tray 31, a paper pressing plate 32, and a paper feed mechanism 33. The paper S stored in the paper feed tray 31 is brought to the upper paper feed mechanism 33 by the paper pressing plate 32, and is fed to the process cartridge 5 (between the photosensitive drum 61 and the transfer roller 63) by the paper feed mechanism 33. Supplied towards.

  The exposure device 4 is disposed in the upper part of the main casing 2 and includes a laser light emitting unit (not shown), a polygon mirror, a lens, a reflecting mirror, and the like that are not shown. In this exposure device 4, the surface of the photosensitive drum 61 is exposed by scanning the surface of the photosensitive drum 61 at high speed with laser light (see the chain line) based on the image data emitted from the laser light emitting unit.

  The process cartridge 5 is disposed below the exposure device 4 and is configured to be detachably mounted to the main body casing 2 through an opening formed when the front cover 2A provided on the main body casing 2 is opened. The process cartridge 5 includes a drum unit 6 and a developing cartridge 7.

  The drum unit 6 mainly includes a photosensitive drum 61, a charger 62, and a transfer roller 63.

  The developing cartridge 7 is detachably attached to the drum unit 6, and is configured to be detachably attached to the main casing 2 as the process cartridge 5 in a state where it is attached to the drum unit 6. The developing cartridge 7 mainly includes a brush roller 11, a blade 12 as an example of a scraping member, and a housing 100. The casing 100 includes a toner storage unit 110 that stores toner T as an example of a developer, and a development unit 120 that is disposed on the rear side of the toner storage unit 110 and is provided with the brush roller 11 and the blade 12. Yes. The configuration of the developing cartridge 7 will be described in detail later.

  In the process cartridge 5, the surface of the photosensitive drum 61 is uniformly charged by the charger 62 and then exposed by high-speed scanning of the laser light from the exposure device 4, whereby image data is transferred onto the photosensitive drum 61. An electrostatic latent image based on is formed. Further, the toner T in the toner container 110 of the developing cartridge 7 is supplied to the brush roller 11. As the brush roller 11 rotates, the blade 12 scrapes off excess toner T on the brush roller 11 and the amount of toner carried on the brush roller 11 is regulated.

  The toner T carried on the brush roller 11 is supplied from the brush roller 11 to the electrostatic latent image formed on the photosensitive drum 61. As a result, the electrostatic latent image is visualized and a toner image is formed on the photosensitive drum 61. Thereafter, the sheet S is conveyed between the photosensitive drum 61 and the transfer roller 63 so that the toner image on the photosensitive drum 61 is transferred onto the sheet S.

  The fixing device 8 is disposed behind the process cartridge 5 and mainly includes a heating roller 81 and a pressure roller 82 that presses the heating roller 81. In the fixing device 8, the toner image transferred onto the paper S is thermally fixed while the paper S passes between the heating roller 81 and the pressure roller 82. The paper S on which the toner image has been thermally fixed is discharged onto a paper discharge tray 22 by a paper discharge roller 23.

  In the state where the process cartridge 5 is mounted on the main casing 2, the fixing device 8, the photosensitive drum 61, the brush roller 11, and the toner storage unit 110 are arranged in this order from the back side of the main casing 2, and are approximately the same height Is arranged. By arranging each member in this way, the size of the main casing 2 in the height direction can be suppressed.

<Detailed configuration of developing cartridge>
Next, the configuration of the developing cartridge 7 will be described in detail.

  As shown in FIG. 2, the housing 100 of the developing cartridge 7 is formed as a container having an opening at the rear, and includes the toner storage portion 110 and the developing portion 120 described above.

  The developing cartridge 7 includes the first conveying member 13 and the second conveying member 14 in the toner storage unit 110, the brush roller 11, the blade 12, the auger 15 as an example of a stirring member, and the return conveying member 16 in the developing unit 120. It has.

  The toner container 110 is formed by connecting a first toner container 111 formed in a substantially cylindrical shape and a second toner container 112 formed in a substantially cylindrical shape. Specifically, the second toner storage unit 112 is disposed on the rear side of the first toner storage unit 111 and is provided at substantially the same height as the first toner storage unit 111. The first toner storage unit 111 and the second toner storage unit 112 are connected to each other at the lower walls and the upper walls, and the insides are in communication.

  The developing unit 120 includes a bottom wall 104 that continuously extends rearward from the rear end of the lower wall 103 of the toner storage unit 110, and a rear obliquely upper surface of the upper wall 102 of the toner storage unit 110 above the second toner storage unit 112. And a fixed wall 105 extending upward. The front portion of the developing unit 120 includes a partition wall 101 that forms the rear portion of the second toner storage unit 112. That is, the toner container 110 and the developing unit 120 are partitioned by the partition wall 101.

  The partition wall 101 is formed so as to connect the upper wall 102 and the lower wall 103 of the toner storage unit 110, and has a circular arc shape protruding rearward.

  The partition wall 101 is provided with a partition 106 as an example of a wall extending rearward from a substantially central portion in the vertical direction. As a result, the space near the partition wall 101 of the developing unit 120 is partitioned by the partition 106, the supply unit 121 is between the partition 106 and the bottom wall 104, and the recovery unit 122 is between the partition 106 and the fixed wall 105.

  The partition 106 is disposed at a position where the tip is higher than the base portion, and is inclined with respect to the horizontal plane so that the upper surface is positioned downward as the partition wall 101 is approached.

  The first transport member 13 is provided in the first toner storage unit 111. The first transport member 13 includes a first base portion 13A that is rotatably supported by the housing 100, and a flexible first sheet member 13B that is fixed to the first base portion 13A.

  The first conveying member 13 is configured such that the tip of the first sheet member 13 </ b> B can be slidably contacted with the inner surface of the first toner containing portion 111 by rotating the first base portion 13 </ b> A clockwise in FIG. 2. Accordingly, the toner T in the first toner storage unit 111 is agitated by the first transport member 13 and the toner T in the first toner storage unit 111 is transported to the second toner storage unit 112. ing.

  The second transport member 14 is provided in the second toner storage unit 112. The 2nd conveyance member 14 is comprised from the 2nd base part 14A rotatably supported by the housing | casing 100, and the flexible 2nd sheet | seat member 14B fixed to the 2nd base part 14A.

  The second transport member 14 is configured such that the tip of the second sheet member 14B can be slidably contacted with the inner surface of the second toner accommodating portion 112 by rotating the second base portion 14A clockwise in FIG. The second conveying member 14 is configured to convey the toner T in the second toner storage unit 112 from the right side to the left side by rotating (see FIG. 3A). As a result, the toner T in the second toner storage unit 112 is agitated by the second transport member 14 and the toner T in the second toner storage unit 112 is moved to the left side to supply the developing unit 120 from a supply port 107 described later. To supply.

  The brush roller 11 has a roller main body 11A formed in a columnar shape, and a brush layer 11B in which fibers are implanted on the outer peripheral surface of the roller main body 11A. The brush roller 11 is disposed such that the rear part is exposed to the outside of the casing 100 through the opening of the casing 100 and is rotatably supported by the casing 100. The brush roller 11 provided in this way can come into contact with the photosensitive drum 61 at a portion exposed from the housing 100.

  The lower portion of the brush roller 11 is in contact with the toner T in the supply unit 121. Specifically, the brush roller 11 is provided on the rear side of the partition 106, and the brush layer 11 </ b> B is provided so as to face the supply unit 121 and the collection unit 122. The partition 106 is close to the brush roller 11 with a gap between the partition 106 and the brush layer 11B.

  The interval between the partition 106 and the brush layer 11B is, for example, when the fiber of the brush roller 11 is 1 mm, the distance between the tip of the partition 106 and the tip of the fiber facing the tip is 0 to 3 mm, more preferably , 0 to 1 mm.

  The blade 12 is formed in a plate shape extending along the axial direction of the brush roller 11. The blade 12 is fixed to the fixed wall 105 above the brush roller 11, extends downward from the fixed position, and has a tip positioned on the front side of the brush roller 11. The blade 12 has its tip bent toward the brush roller 11 and enters the brush layer 11B.

  Specifically, the tip of the blade 12 is in contact with the brush roller 11 in the collection unit 122, that is, above the position where the brush roller 11 faces the toner T in the supply unit 121. The partition 106 is disposed below the position where the blade 12 contacts the brush roller 11.

  The auger 15 is provided in the supply unit 121 and is disposed so as to face the surface of the brush roller 11 and a supply port 107 described later. The auger 15 is configured to rotate and move the toner T in the supply unit 121 from the left to the right while stirring and uniformly supply the brush roller 11 with stirring.

  The return conveyance member 16 is provided in the vicinity of the blade 12, that is, in the collection unit 122. The return conveying member 16 includes a third base portion 16A that is rotatably supported by the housing 100, and a flexible third sheet member 16B that is fixed to the third base portion 16A.

  The return conveyance member 16 is movable while the third base member 16A rotates counterclockwise in FIG. 2 so that the third sheet member 16B is in sliding contact with the partition 106 or the partition wall 101. . As a result, the toner T scraped off by the blade 12 is conveyed by the return conveying member 16 from the second return port 109 described later toward the second toner accommodating portion 112.

  As shown in FIG. 3A, the partition wall 101 is formed with a supply port 107 and a first return port 108 that allow the second toner storage unit 112 and the supply unit 121 to communicate with each other at a position facing the supply unit 121. ing.

  The supply port 107 is provided at the left end portion of the partition wall 101. The first return port 108 is provided at the right end of the partition wall 101.

  And the 2nd conveyance member 14 has the 2nd sheet | seat member 14B with several 1st sheet | seat 14C and 2nd sheet | seat 14D which are located in a line with the left-right direction. The plurality of first sheets 14 </ b> C have their tips inclined with respect to the rotation axis of the second conveying member 14 so that the toner T can be conveyed from the right to the left when the second conveying member 14 rotates. Yes. The second sheet 14D is disposed at a position corresponding to the supply port 107 in the left-right direction. The second sheet 14 </ b> D has a leading end substantially parallel to the rotation axis of the second transport member 14 so that the toner T in the second toner storage unit 112 can be transported straight toward the supply port 107.

  Further, as shown in FIG. 3B, the partition wall 101 is formed with a second return port 109 through which the second toner storage unit 112 and the recovery unit 122 communicate with each other at a position facing the recovery unit 122. . The second return port 109 is provided from the left end to the right end of the partition wall 101. As shown in FIG. 2, the second return port 109 has a lower end edge formed in the vicinity of the root portion of the partition 106.

  By providing such a second return port 109, a return path 130 is formed in the housing 100 that connects the second return port 109 to the supply port 107 via the second toner storage portion 112.

The operation and effect of the developing cartridge 7 configured as described above will be described.
As shown in FIG. 3A, when the first transport member 13 and the second transport member 14 rotate, the toner T in the toner storage unit 110 is brought closer to the supply port 107, and from the supply port 107 to the developing unit 120. To the supply unit 121.

  The toner T supplied to the supply unit 121 moves from the left to the right in the supply unit 121 as the auger 15 rotates, and spreads throughout the supply unit 121. The toner T that has not been supplied to the brush layer 11 </ b> B moves to the right end of the supply unit 121 and is then returned from the first return port 108 to the second toner storage unit 112.

  When a large amount of toner T is supplied from the second toner storage unit 112 into the supply unit 121, the water level of the toner T in the vicinity of the brush roller 11 in the supply unit 121 is suppressed by the partition 106 as shown in FIG. Can do. As a result, it is possible to prevent the toner T in the supply unit 121 from entering the recovery unit 122 and filling the toner T around the portion of the blade 12 that is in contact with the brush roller 11.

  When the brush roller 11 rotates, the toner T is supplied to the brush layer 11 </ b> B when facing the toner T in the supply unit 121. Since the toner T in the supply unit 121 is spread over the entire supply unit 121 by the auger 15, the toner T is supplied to the brush roller 11 substantially uniformly in the left-right direction.

  The brush layer 11 </ b> B holding the toner T faces the tip of the partition 106. At this time, if excessive toner T is placed on the brush layer 11B, the excessive toner T contacts the partition 106 and is scraped off to some extent.

  When the brush roller 11 further rotates, the blade 12 comes into contact with the brush layer 11B that has passed the position facing the tip of the partition 106, and excess toner T held on the brush layer 11B is scraped off by the blade 12.

  At this time, in the present embodiment, as described above, the partition 106 is provided between the supply unit 121 and the collection unit 122, so that the contact portion between the brush roller 11 and the blade 12 is not filled with the toner T, and A certain amount of toner T is scraped off by the partition 106 before the blade 12 scrapes off the toner T of the brush layer 11B. Thereby, since the toner T does not exist excessively in the vicinity of the contact portion between the brush roller 11 and the blade 12, the excess toner T held by the brush layer 11B can be scraped off favorably by the blade 12.

  Then, the toner T scraped off by the blade 12 falls onto the partition 106. The toner T that has fallen on the partition 106 is returned to the second toner container 112 from the second return port 109 and mixed with the toner T in the second toner container 112. That is, the toner T scraped off by the blade 12 is not directly returned to the supply unit 121 but is supplied again to the supply unit 121 through the return path 130 passing through the toner storage unit 110. Thus, the scraped toner T does not stay in the vicinity of the blade 12 or in the developing unit 120, and the toner T can be circulated in the housing 100.

  Further, since the return conveyance member 16 is provided in the collection unit 122, the toner T scraped off by the blade 12 can be easily moved toward the return path 130. Since the upper surface of the partition 106 is inclined so as to be lowered toward the second return port 109, the toner T of the partition 106 can be easily moved toward the second return port 109.

  In the first embodiment described above, the supply port 107 is provided at the left end of the partition wall 101 and the first return port 108 is provided at the right end of the partition wall 101. However, the present invention is not limited to this. Is not to be done. For example, the supply port 107 may be provided at the right end of the partition wall 101, and the first return port 108 may be provided at the left end of the partition wall 101.

  For example, as illustrated in FIG. 4, the supply port 107 </ b> A may be provided at a substantially central portion in the left-right direction of the partition wall 101, and the first return ports 108 </ b> A may be provided at both left and right ends of the partition wall 101.

  In this case, the second transport member 14 is configured to transport the toner T in the second toner storage unit 112 from both the left and right end portions to the central portion. A portion of the second conveying member 14 corresponding to the supply port 107A in the left-right direction of the second sheet member 14B is formed so that the toner T collected at the center can be conveyed toward the supply port 107A.

  In the above-described first embodiment, the supply port 107 and the first return port 108 are provided as the openings that allow the second toner storage unit 112 and the supply unit 121 of the developing unit 120 to communicate with each other. It is not limited to this. For example, as shown in FIG. 5, one large communication port 107 </ b> B may be provided at a position corresponding to the supply unit 121 of the partition wall 101.

  Specifically, the communication port 107 </ b> B is provided from the left end to the right end of the partition wall 101. The second transport member 14 is configured to be able to transport the toner T in the second toner storage unit 112 straight toward the supply unit 121 at any position in the left-right direction.

  In this case, the supply unit 121 may be provided with a stirring member 17 that does not have a configuration for conveying the toner T in the left-right direction like the auger 15 in the first embodiment. The stirring member 17 has a bar 17A that is disposed at a position shifted in the radial direction from the rotation axis. The bar 17 </ b> A is formed long along the axial direction of the brush roller 11. Then, as the stirring member 17 rotates, the bar 17A rotates in the supply unit 121 in the clockwise direction in FIG. 5A around the rotation axis, and the toner T in the supply unit 121 is stirred. Yes.

  In the first embodiment described above, the partition 106 (wall) is formed in a plate shape, but the present invention is not limited to this. For example, the wall may be configured by arranging a plurality of rod-shaped members extending from the partition wall 101 or the left and right side walls of the developing unit 120 with a slight gap.

[Second Embodiment]
Next, a second embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the second embodiment, the wall that partitions the supply unit and the recovery unit is configured by a wall that partitions the toner storage unit and the development unit. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As illustrated in FIG. 6, the housing 200 of the developing cartridge 7 </ b> C includes a toner container 210 and a developing unit 220 provided on the rear side of the toner container 210. In the toner storage unit 210, the conveying member 18 is provided, and in the developing unit 220, the brush roller 11, the blade 12, and the auger 15 are provided.

  The toner container 210 is formed in a substantially cylindrical shape. The wall constituting the rear portion of the toner storage unit 210 is a partition wall 201 that partitions the toner storage unit 210 and the development unit 220. The partition wall 201 has a shape protruding toward the developing unit 220, and a space near the partition wall 201 of the developing unit 220 is provided to the supply unit 221 and the recovery unit 222 disposed on the supply unit 221. It is divided.

  Specifically, the developing unit 220 includes a bottom wall 204 that extends rearward from the lower part of the toner storage unit 210, and a fixed wall 205 that extends rearward from the upper part of the toner storage unit 210. The supply unit 221 is formed in a substantially cylindrical shape, and the front part enters the toner storage unit 210. That is, the partition wall 201 has an arc shape with a lower portion projecting forward and an upper portion with an arc shape projecting backward. The corner 201A (wall) having the two arcs connected to each other and having a surface facing downward is arranged between the blade 12 provided in the developing unit 220 and the auger 15 in the vertical direction.

  Further, the corner portion 201 </ b> A of the partition wall 201 faces the brush roller 11 below the position where the blade 12 contacts the brush roller 11. The corner 201A is close to the brush roller 11 with a gap between the brush roller 11 and the brush layer 11B.

  Since the corner portion 201A of the partition wall 201 is disposed with a gap between the brush layer 11B, the toner T scraped off by the blade 12 is supplied between the partition wall 201 and the brush roller 11 to the supply unit 221. A return path 230 for returning to is formed.

  A supply port 207 and a return port 209 that allow the supply unit 221 and the toner storage unit 210 to communicate with each other are formed in the partition wall 201 at positions corresponding to the supply unit 221. The supply port 207 is provided at the left end portion of the partition wall 201 and opens upward. The return port 209 is provided at the right end of the partition wall 201 below the supply port 207, more specifically, below the supply unit 221.

  The conveying member 18 includes a base portion 18A that is rotatably supported by the casing 200, and a flexible sheet member 18B that is fixed to the base portion 18A.

  The conveying member 18 is configured such that the base portion 18A rotates counterclockwise in FIG. 6A so that the front end of the sheet member 18B can slide on the inner surface of the toner accommodating portion 210. Further, the conveying member 18 is configured to convey the toner T in the toner storage unit 210 from the right to the left by rotating. As a result, the toner T in the toner storage unit 210 is agitated by the conveying member 18, and the toner T in the toner storage unit 210 is moved to the left and supplied from the supply port 207 to the supply unit 221. .

The operation and effect of the developing cartridge 7C configured as described above will be described.
When the transport member 18 rotates, the toner T in the toner storage unit 210 is supplied from the supply port 207 to the supply unit 221. The toner T supplied to the supply unit 221 moves from the left to the right in the supply unit 221 as the auger 15 rotates, and spreads throughout the supply unit 221. The toner T that has not been supplied to the brush layer 11 </ b> B moves to the right end of the supply unit 221 and is then returned to the toner storage unit 210 from the return port 209.

  When a large amount of toner T is supplied to the supply unit 221, the water level of the toner T in the supply unit 221 is suppressed by the corner portion 201 </ b> A of the partition wall 201. As a result, it is possible to prevent the toner T in the developing unit 220 from entering the collecting unit 222 and filling the position where the blade 12 contacts the brush roller 11 with the toner T, so that the brush layer 11B is held by the blade 12. The toner T to be scraped off can be satisfactorily scraped off.

  The toner T scraped off by the blade 12 falls to the supply unit 221 through the return path 230. The toner T that has fallen into the supply unit 221 is mixed with the toner T in the supply unit 221 and supplied again to the brush roller 11 or returned to the toner storage unit 210 from the return port 209.

  In the second embodiment described above, the supply port 207 and the return port 209 are provided separately, but the present invention is not limited to this. For example, the partition wall 201 is provided with an opening that is long in the left-right direction, through which the toner T of the toner storage unit 210 is supplied to the supply unit 221, and the toner T of the supply unit 221 moves to the toner storage unit 210. It may be configured.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. About a concrete structure, it can change suitably in the range which does not deviate from the meaning of this invention.

  In the above embodiment, the developing cartridges 7 and 7C have the partition walls 101 and 201 that partition the toner storage portions 110 and 210 and the developing portions 120 and 220. However, the present invention is not limited to this. Absent. For example, the developing cartridge has a configuration in which only a wall that divides the space around the brush roller 11 up and down is provided as a wall that divides the space in the housing, without a partition wall that divides the toner storage portion and the developing portion. There may be.

  In the above-described embodiment, in the developing cartridges 7 and 7C, the toner storage portions 110 and 210 and the developing portions 120 and 220 are integrated, but the present invention is not limited to this. For example, the developing cartridge may include a developing unit and a toner storage unit that can be attached to and detached from the developing unit.

7 Developing Cartridge 11 Brush Roller 11A Roller Body 11B Brush Layer 12 Blade 15 Auger 16 Return Conveying Member 100 Housing 107 Supply Port 109 Second Return Port 110 Toner Storage Portion 121 Supply Portion 130 Return Path 200 Housing 201A Corner Portion 210 Toner Storage Part 221 supply part 230 return path T toner

Claims (6)

A housing having a supply section capable of storing developer;
A brush body having a roller body and a brush layer in which fibers are implanted on the outer peripheral surface of the roller body, and being supported by the housing so as to be in contact with the developer in the supply unit;
A scraping member configured to contact the brush roller above a position where the brush roller faces the developer in the supply unit and scrape off the developer held on the brush layer; Prepared,
The housing is disposed so as to face the brush roller below a position where the scraping member contacts the brush roller, and a wall capable of suppressing a developer water level in the vicinity of the brush roller in the supply unit. A developing device comprising:   The developing device according to claim 1, wherein the wall is close to the brush roller with a gap between the wall and the brush layer.   The developing device according to claim 1, wherein the housing includes a return path configured to return the developer scraped by the scraping member to the supply unit. . The housing has a developer accommodating portion capable of accommodating a developer supplied to the supply portion,
The developing device according to claim 3, wherein the return path passes through the developer accommodating portion.   5. The developing device according to claim 4, further comprising a return transporting member that is provided in the vicinity of the scraping member and transports the developer scraped by the scraping member toward the return path. 6.   The developing device according to claim 1, wherein the supply unit includes a stirring member configured to stir the developer in the supply unit.

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