JP2008249922A - Developer storage body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer storage body capable of suppressing unevenness of density of an image by satisfactorily dispersing toner within a developing chamber. <P>SOLUTION: An agitator 200 includes: a rotary shaft 201 rotatable within a storage chamber AR; a feeding blade 205b extending out in the radial direction of the rotary shaft 201; and an agitating blade 204b disposed while being shifted from the feeding blade 205b in the axial direction of the rotary shaft 201 and extending outside of the rotary shaft 201. A wall (cylindrical wall 101) forming the storing chamber AR has a supply port 103 for supplying developer to the outside and a return port 104 for allowing return of developer from the outside. The feeding blade 205b is constituted such that a distance from the rotary shaft 201 to the leading edge of the feeding blade 205b is longer than a distance from the rotary shaft 201 to the leading edge of the stirring blade 204b. The feeding blade 205b is disposed while being shifted from the stirring blade 204b in the rotating direction of the rotary shaft 201. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a developer container including an agitator.

  In general, an image forming apparatus such as a laser printer includes a photosensitive drum for supplying toner to a sheet, a process cartridge having a developing roller and a developing chamber for supplying toner to the photosensitive drum, and a toner cartridge for storing the toner. And. In such an image forming apparatus, the toner in the toner cartridge is supplied into the developing chamber on the process cartridge side by the blades of the agitator having a plurality of blades rotating in the toner cartridge.

  As such an agitator, conventionally, a rotating shaft rotatably supported on an end wall of a hollow cylindrical toner cartridge, a plurality of wings disposed along the axial direction of the rotating shaft, and a cylinder of the toner cartridge There has been known one provided with a plurality of toner supply ports formed on a cylindrical peripheral wall side by side in the axial direction (see Patent Document 1). In this technique, the plurality of wings are formed with the same length, whereby each wing supplies the toner from the plurality of toner supply ports to the developing chamber with the same conveying force.

JP-A-9-166911

  However, in the conventional technique, since each blade is formed with the same length, the force for conveying the toner to the developing chamber is the same in each blade, so that the toner is pushed out from the toner cartridge toward the developing chamber. Therefore, there is a possibility that the toner is not uniformly dispersed in the developing chamber. As a result, the density of the formed image may be uneven.

  Therefore, an object of the present invention is to provide a developer container that can suppress unevenness in image density by favorably dispersing toner in a developing chamber.

  The present invention that solves the above-described problems is a developer container including a storage chamber that stores a developer and an agitator that rotates in the storage chamber and stirs the developer, and the agitator includes the storage chamber. A rotating shaft rotatably held on a wall forming a chamber, a feed blade extending from the inner side to the outer side in the radial direction of the rotating shaft, and disposed at a position shifted from the feed blade in the axial direction of the rotating shaft, A stirring blade extending from the inner side to the outer side in the radial direction of the rotating shaft, and the wall forming the storage chamber is disposed at a position overlapping the feeding blade in the radial direction of the rotating shaft, and the developer A supply port for supplying to the outside and a return port arranged at a position overlapping the stirring blade in the radial direction of the rotation shaft and allowing the developer to return from the outside are formed, and the feed blade is configured to rotate the rotation blade. Distance from shaft to tip of feed wing Wherein while being configured to be longer than the distance from the rotational axis to the tip of the stirring blade, characterized in that arranged staggered with respect to the stirring blade in the rotational direction of the rotary shaft.

  Further, the present invention is a developer container including a storage chamber that stores a developer and an agitator that rotates in the storage chamber and stirs the developer, and the agitator forms the storage chamber A rotating shaft that is rotatably supported by the wall, a feed blade that extends from the inner side to the outer side in the radial direction of the rotating shaft, and a position that is offset from the feed blade in the axial direction of the rotating shaft, And a supply port for supplying the developer to the outside, disposed on the wall forming the storage chamber at a position overlapping with the feed blade in the radial direction of the rotation shaft. And a stirrer blade and a return port that is arranged at a position overlapping in the radial direction of the rotating shaft and allows the developer to return from the outside, and the feed vane is more rigid than the stirrer blade , In the rotation direction of the rotating shaft Characterized in that arranged offset relative to the stirring blade.

  According to the present invention, since the feed blade is formed longer or stiffer than the stirring blade, the feeding force of the feed blade is larger than that of the stirring blade. Then, the developer is pushed out of the storage chamber from the supply port by the feeding blade having a large conveyance force, whereas the developer is hardly pushed out of the storage chamber from the return port by the stirring blade having a small conveyance force. Therefore, the developer that has once exited from the supply port can return from the return port, and the developer can be favorably dispersed in the developing chamber outside the storage chamber.

By the way, when the developer is conveyed to the outside of the storage chamber by the feed blade, the amount of the developer is reduced in the region where the feed blade has passed in the storage chamber. Need to supply.
If the feed blade and the stirring blade are arranged without shifting in the rotation direction of the rotating shaft of the agitator, the feeding blade and the stirring blade overlap in the rotation axis direction of the agitator, and the feeding blade becomes an obstacle, It may be difficult to satisfactorily supply the developer to the region through which the feed blades pass.

  Therefore, in the present invention, since the feed blade and the stirring blade are arranged in a state of being shifted in the rotation direction of the rotating shaft of the agitator, the developing blade is used to develop the region where the feed blade has passed and the developer is reduced. It becomes possible to convey the agent easily. Thus, since the developer is always supplied satisfactorily to the region through which the feed blade passes, the developer can be satisfactorily supplied to the developing chamber outside the storage chamber by the feed blade.

According to the present invention, it is possible to return the developer once outside from the supply port from the return port by increasing the conveying force of the feed blade rather than the stirring blade, and the developer is developed outside the storage chamber. Since it can be favorably dispersed in the chamber, unevenness in image density can be suppressed.
Further, since the developer can be favorably dispersed in the developing chamber by transporting the developer to the developing chamber outside the storage chamber by the feeding blade, unevenness in the density of the image can be suppressed. .

  Next, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the drawings to be referred to, FIG. 1 is a side sectional view showing a laser printer according to an embodiment of the present invention. In the following description, first, the overall configuration of the laser printer will be briefly described, and then the details of the characteristic portions of the present invention will be described. Further, in the following description, the description will be made in the direction based on the user when the laser printer 1 is used. That is, in FIG. 1, the right side is referred to as “front side”, the left side is referred to as “back side”, the back side in the vertical direction of the paper surface is referred to as “right side”, and the front side in the vertical direction of the paper surface is referred to as “left side”. Called. As for the up and down direction, the illustrated direction and the direction when used by the user coincide with each other, and therefore will be referred to as the “up and down direction” as they are.

<Overall configuration of laser printer>
As shown in FIG. 1, a laser printer 1 as an example of an image forming apparatus includes a feeder unit 4 for feeding paper 3 into a main body casing 2 as an example of a main body of an image forming apparatus, and fed paper. 3 includes an image forming section 5 for forming an image.

<Configuration of feeder section>
The feeder unit 4 includes a paper feed tray 6 that is detachably attached to the bottom of the main casing 2 and a paper pressing plate 7 provided in the paper feed tray 6. The feeder unit 4 includes various rollers 11 that carry the paper 3 and remove paper dust.

  In the feeder unit 4 configured as described above, the sheet 3 in the sheet feeding tray 6 is moved upward by the sheet pressing plate 7 and conveyed to the image forming unit 5 by various rollers 11.

<Configuration of image forming unit>
The image forming unit 5 includes a scanner unit 16, a process cartridge 17, a fixing unit 18, and the like.

<Configuration of scanner unit>
The scanner unit 16 is provided at an upper portion in the main body casing 2 and includes a laser light emitting unit (not shown), a polygon mirror 19 that is rotationally driven, lenses 20, 21 and reflecting mirrors 22, 23, 24, and the like. . The laser beam based on the image data emitted from the laser emitting unit passes or reflects in the order of the polygon mirror 19, the lens 20, the reflecting mirror 22, the reflecting mirror 23, the lens 21, and the reflecting mirror 24, as indicated by a chain line, The surface of the photosensitive drum 27 of the process cartridge 17 is irradiated with high-speed scanning.

<Process cartridge configuration>
The process cartridge 17 is configured to be detachably attached to the main casing 2 by appropriately opening a front cover 2 a provided on the front side of the main casing 2. The process cartridge 17 is mainly composed of a developing cartridge 28 and a drum unit 51.

  The developing cartridge 28 is detachably attached to the main casing 2 while being attached to the drum unit 51. The developing cartridge 28 may be configured to be detachable from the drum unit 51 fixed to the main casing 2.

  As shown in FIG. 2, the developing cartridge 28 mainly includes a developing roller 31, a layer thickness regulating blade 32, and a supply roller 33. The developing roller 31, the layer thickness regulating blade 32, an upper wall 28a, and a lower wall 28b. And a developing chamber DR formed by the rear wall 28c (front wall). A toner cartridge 100, which will be described in detail later, is detachably mounted on the back wall 28c of the developing chamber DR. The toner in the toner cartridge 100 is agitated by an agitator 200, which will be described in detail later, and then supplied to the developing roller 31 by the supply roller 33. At this time, the toner is positively supplied between the supply roller 33 and the developing roller 31. Frictional charge. The toner supplied onto the developing roller 31 enters between the layer thickness regulating blade 32 and the developing roller 31 as the developing roller 31 rotates, and slides between the layer thickness regulating blade 32 and the developing roller 31. By being in contact therewith, it is carried on the developing roller 31 as a thin layer having a constant thickness. In this embodiment, the toner as an example of the developer is a positively charged non-magnetic one-component polymerized toner.

  The drum unit 51 mainly includes a photosensitive drum 27, a scorotron charger 29, and a transfer roller 30.

The photosensitive drum 27 is rotatably supported by the casing of the drum unit 51.
The scorotron charger 29 is a positively charged scorotron charger that generates corona discharge from a charging wire such as tungsten, and is configured to uniformly charge the surface of the photosensitive drum 27 to a positive polarity. Yes.

  The transfer roller 30 is arranged below the photosensitive drum 27 so as to face and contact the photosensitive drum 27, and is rotatably supported by the casing of the drum unit 51. A transfer bias is applied to the transfer roller 30 by constant current control during transfer.

  The surface of the photosensitive drum 27 is uniformly positively charged by the scorotron charger 29 and then exposed by high-speed scanning of the laser beam from the scanner unit 16 (see FIG. 1). Thereby, the potential of the exposed part is lowered, and an electrostatic latent image based on the image data is formed. Here, the “electrostatic latent image” refers to an exposed portion of the surface of the photosensitive drum 27 that is uniformly positively charged and exposed to a laser beam to have a lowered potential. Next, the rotation of the developing roller 31 causes the toner carried on the developing roller 31 to be supplied to an electrostatic latent image formed on the surface of the photosensitive drum 27 when it contacts and faces the photosensitive drum 27. The The toner is visualized by being selectively carried on the surface of the photosensitive drum 27, whereby a toner image is formed by reversal development.

  Thereafter, the photosensitive drum 27 and the transfer roller 30 are rotationally driven so as to sandwich and convey the sheet 3 between them, and the sheet 3 is conveyed between the photosensitive drum 27 and the transfer roller 30, so that the photosensitive drum 27 and the transfer roller 30 are photosensitive. The toner image carried on the surface of the drum 27 is transferred onto the paper 3.

<Configuration of fixing unit>
As shown in FIG. 1, the fixing unit 18 is provided on the downstream side of the process cartridge 17, and includes a heating roller 41 and a pressure roller 42 that is disposed to face the heating roller 41 and pressurizes the heating roller 41. ing. In the fixing unit 18 configured as described above, the toner transferred onto the paper 3 is thermally fixed while the paper 3 passes between the heating roller 41 and the pressure roller 42. The sheet 3 thermally fixed by the fixing unit 18 is conveyed to a paper discharge roller 45 disposed on the downstream side of the fixing unit 18, and is sent out from the paper discharge roller 45 onto a paper discharge tray 46.

<Detailed structure of toner cartridge>
Next, the detailed structure of the toner cartridge 100 as an example of the developer container according to the present invention will be described. In the drawings to be referred to, FIG. 2 is a sectional view showing a detailed structure of the toner cartridge, and FIG. 3 is a perspective view showing a supply port and a return port of the toner cartridge. FIG. 4 is a perspective view (a) showing the agitator and a schematic diagram (b) showing the relationship between the feed blade, the stirring blade, the supply port and the return port.

  As shown in FIG. 2, the toner cartridge 100 includes a storage chamber AR that stores toner, and an agitator 200 that rotates in the storage chamber AR to stir the toner.

  As shown in FIG. 3, the storage chamber AR is formed by a substantially cylindrical tubular wall 101 and substantially circular end walls 102 provided at both ends of the tubular wall 101. Then, at an appropriate position (backward appropriate position) of the cylindrical wall 101, a supply port 103 for supplying toner from the inside of the storage chamber AR to the inside of the developing chamber DR (see FIG. 2), and the toner in the developing chamber DR The return ports 104 for allowing the return into the storage chamber AR are alternately formed at predetermined intervals along the axial direction. In other words, between the supply port 103 and the return port 104, a partition portion 101a having a predetermined width as an example of a partition member is interposed. As shown in FIG. 2, a plurality of through holes 28d corresponding to the supply port 103 and the return port 104 are formed in the back wall 28c of the developing cartridge 28 (see FIG. 5A). A partition portion 28f having a width smaller than that of the partition portion 101a is interposed between the adjacent through holes 28d. Further, the supply port 103 and the return port 104 are arranged at the same position (phase) in the rotation direction of the agitator 200 and overlap in the rotation axis direction of the agitator 200.

As shown in FIG. 4A, the agitator 200 includes a rotating shaft 201, a stirring blade support 202, a feeding blade support 203, a stirring blade connection body 204, and a feeding blade connection body 205.
The rotation shaft 201 is rotatably held by two end walls 102 (see FIG. 3) among the walls forming the storage chamber AR. More specifically, as shown in FIG. 5A, the rotation shaft 201 is rotatably supported by a recess 102a and a hole 102b formed in the end wall 102.

  The stirring blade support 202 extends from the rotating shaft 201 radially outward and has a plurality of arms 202a arranged at predetermined intervals in the axial direction and the arms so as to connect the tips of the arms 202a. And a wing support portion 202b formed integrally with the portion 202a.

  Like the stirring blade support 202, the feed blade support 203 includes a plurality of arm portions 203a and a blade support portion 203b. The feed blade support 203 is formed to extend from the rotating shaft 201 toward the side opposite to the stirring blade support 202.

  The stirring blade coupling body 204 is formed of a film-like member that can be bent and deformed, and mainly has a long fixing portion 204a that is fixed to the distal end surface of the stirring blade support 202 and the length of the fixing portion 204a. A plurality of stirring blades 204b extending along the short side direction from one end edge serving as a side are provided. The respective stirring blades 204b are arranged at predetermined intervals in the axial direction of the rotating shaft 201, and are formed so as to extend from the front end surface of the stirring blade support 202 toward the radially outer side of the rotating shaft 201. Yes. Specifically, as shown in FIG. 2, each stirring blade 204b is disposed so as to be inclined from the downstream side to the upstream side in the rotational direction of the agitator 200 as it goes from the radially inner side to the outer side of the rotating shaft 201. .

  Each stirring blade 204b is arranged corresponding to each return port 104 as shown in the schematic diagram of FIG. In other words, each stirring blade 204 b is arranged at a position overlapping with each return port 104 in the radial direction of the rotating shaft 201. Furthermore, the horizontal width W1 (the dimension in the axial direction of the rotating shaft 201) of each stirring blade 204b is formed to be larger than the horizontal width W2 of each return port 104. Here, each arrow shown on the right side of FIG. 4B indicates the flow of toner.

  As shown in FIG. 4 (a), the feeding blade coupling body 205 is formed of a film-like member that can be bent and deformed similarly to the stirring blade coupling body 204. And a plurality of feed blades 205b extending from one end edge which is the long side of the fixed portion 205a along the short side direction. The feed blades 205b are arranged at predetermined intervals in the axial direction of the rotary shaft 201, and are formed so as to extend from the front end surface of the feed blade support 203 toward the radially outer side of the rotary shaft 201. Yes. Specifically, as shown in FIG. 2, each feed blade 205 b is disposed so as to incline from the downstream side to the upstream side in the rotational direction of the agitator 200 as it goes from the radially inner side to the outer side of the rotary shaft 201. .

  Each feed blade 205b is arranged at a position shifted from each stirring blade 204b in the axial direction of the rotating shaft 201, as shown in FIG. In other words, each stirring blade 204b is disposed between each feeding blade 205b. The length of each feed blade 205b (distance from the rotation shaft 201 to the tip of the feed blade 205b) is longer than the length of each stirring blade 204b (distance from the rotation shaft 201 to the tip of the stirring blade 204b). It is formed to be long. Specifically, as shown in FIG. 2, each feed blade 205b is formed with a length that can be slidably contacted with the cylindrical wall 101, which is a wall that forms the storage chamber AR, whereas each stirring blade 204b has a cylindrical shape. It is formed with a length that is a predetermined distance away from the wall 101. Further, each feed blade 205 b is provided on a feed blade support 203 that extends on the opposite side of the stirring blade support 202, so that each feed blade 205 b is shifted by 180 ° with respect to each stirring blade 204 b in the rotation direction of the rotating shaft 201. ing.

  Further, each feed blade 205b is arranged corresponding to each supply port 103, as shown in the schematic diagram of FIG. In other words, each feed blade 205 b is arranged at a position overlapping with each supply port 103 in the radial direction of the rotating shaft 201. Further, the lateral width W3 (the dimension along the axial direction of the rotating shaft 201) of each feed blade 205b is formed to be larger than the lateral width W4 (maximum dimension) of each supply port 103.

  Next, the movement of the toner conveyed by the agitator 200 according to the present embodiment will be described. In the drawings to be referred to, FIG. 5 is a cross-sectional view (a) showing the flow of toner, an XX cross-sectional view (b) in FIG. 5 (a), and a YY cross-sectional view in FIG. c).

  As shown in FIG. 5B, when the agitator 200 is rotated and the long feed blade 205b slidably contacting the cylindrical wall 101 moves to the vicinity of the supply port 103, the toner in the storage chamber AR is moved by the feed blade 205b. Is conveyed into the developing chamber DR. At this time, when the toner is sufficiently accumulated in the space below the through hole 28d corresponding to the supply port 103 (the space in the developing chamber DR), as shown in FIG. Toner flows from the supply port 103 side to the return port 104 side.

  At this time, as shown in FIG. 5C, if the toner is sufficiently accumulated in the space below the through hole 28d corresponding to the return port 104 (the space in the developing chamber DR), the toner has penetrated. It returns into the storage chamber AR through the hole 28d and the return port 104. In particular, at this time, the stirring blade 204b is positioned at a position away from the return port 104 by being disposed at a position shifted from the feeding blade 205b in the rotation direction. Therefore, it is possible to satisfactorily return the toner into the storage chamber AR without disturbing the return of the toner from the return port 104 arranged at the same position as the supply port 103 in the rotation direction of the agitator 200. Further, even if the stirring blade 204b moves to the vicinity of the return port 104, the stirring blade 204b is formed shorter than the feed blade 205b, so that the force for feeding the toner to the developing chamber DR is weak. Therefore, the toner flow that reverses the toner circulation direction shown in FIG. 5A does not occur, and the toner can be favorably dispersed in the developing chamber DR.

  Further, as shown in FIG. 5B, immediately after the toner is fed to the supply port 103 by the feed blade 205b, the toner is reduced from the region through which the feed blade 205b passes (the bottom portion of the cylindrical wall 101). To do. On the other hand, as shown in FIG. 5C, a large amount of toner is accumulated in the region (the bottom portion of the cylindrical wall 101) through which the stirring blade 204b is to pass. For this reason, a large amount of accumulated toner is destroyed by the stirring blade 204b that is shifted in the rotation direction from the feeding blade 205b, and the toner is supplied to the region through which the feeding blade 205b has passed.

According to the above, the following effects can be obtained in the present embodiment.
By making the feeding blade 205b longer than the stirring blade 204b, the conveying force of the feeding blade 205b can be made larger than that of the stirring blade 204b. Further, by shifting the stirring blade 204b and the feeding blade 205b in the rotation direction, it is possible to suppress the stirring blade 204b from becoming a resistance against the toner returning from the return port 104. Therefore, since the toner can be circulated favorably between the developing chamber DR and the storage chamber AR and the toner can be favorably dispersed in the developing chamber DR, unevenness in image density can be suppressed.

  A large amount of accumulated toner is destroyed by the stirring blade 204b shifted in the rotation direction from the feeding blade 205b, and the toner is supplied to an area where the feeding blade 205b passes and the toner is reduced. In addition, since a large amount of toner can be transported by the feeding blade 205b, the toner can be supplied to the developing chamber DR in a better manner.

Furthermore, in this embodiment, polymerized toner having extremely high fluidity compared to pulverized toner or the like is used, so that the toner can be circulated more reliably and density unevenness of the image can be more reliably suppressed. It becomes possible.
By the way, although non-magnetic one-component toner is used in this embodiment, in the configuration using non-magnetic one-component toner, the supply roller 33 and the developing roller 31 are used for the purpose of charging the toner. It is necessary to bring the toner into sliding contact with each other and between the layer thickness regulating blade 32 and the developing roller 31. Then, the toner deteriorates as it is slidably contacted, and becomes difficult to be charged. If the toner thus deteriorated (deteriorated toner) accumulates without being circulated into the developing chamber DR, the toner that has not deteriorated (good toner) in the storage chamber AR and the deteriorated toner accumulated in the developing chamber DR are non-uniform. It will be mixed in a state. In this way, when the deteriorated toner and the good toner having different charging characteristics are non-uniformly mixed and used for image formation, density unevenness may occur in the formed image. Therefore, in the configuration according to the present invention, the toner is circulated well between the developing chamber DR and the storage chamber AR, and the good toner and the deteriorated toner are almost uniformly mixed in the developing chamber DR. Even when non-magnetic one-component toner is used, uneven density of the image is suppressed.

Since the lateral width W3 of the feed blade 205b that is in sliding contact with the cylindrical wall 101 is formed to be larger than the lateral width W4 of the supply port 103, the supply blade 103 is blocked when the feed blade 205b passes through the supply port 103. The return of toner from the opening 103 into the storage chamber AR is suppressed. Therefore, the toner can be circulated better between the developing chamber DR and the storage chamber AR.
In addition, a partition portion 101a having a predetermined width as an example of a partition member is interposed between the supply port 103 and the return port 104, and a partition portion having a smaller width than the partition portion 101a is provided between adjacent through holes 28d. Since 28f is interposed, it is possible to satisfactorily guide the toner supplied from the supply port 103 to the developing chamber DR toward the return port 104.

In addition, this invention is not limited to the said embodiment, It can utilize with various forms so that it may illustrate below.
In the above embodiment, both the feed blade 205b and the stirring blade 204b are larger than the lateral width of the supply port 103 and the return port 104, but the present invention is not limited to this. For example, as shown in FIG. 6A, the lateral width of the feed blade 205b may be the same as that of the supply port 103, and the lateral width of the stirring blade 204b may be the same as that of the return port 104. Further, as shown in FIG. 6B, the lateral width of the feed blade 205b may be made larger than that of the supply port 103, and the lateral width of the stirring blade 204b may be made smaller than that of the return port 104. As shown in FIG. 6B, it is preferable to make the width of the stirring blade 204b smaller than that of the return port 104 because the toner conveying force by the stirring blade 204b can be further weakened.

  In the above embodiment, one supply port 103 is provided for each feed blade 205b and one return port 104 is provided for each stirring blade 204b. However, the present invention is limited to this. is not. For example, as shown in FIG. 6C, two (plurality) supply ports 105 are provided for one feed blade 205b, and two (plurality) return ports 106 are provided for one stirring blade 204b. It may be provided. In addition, as shown in FIG. 6D, the supply port and the return port may be formed as one hole 107.

  In the above embodiment, the feed blade 205b is configured not to protrude from the supply port 103 toward the developing chamber DR. However, the present invention is not limited to this, and the tip of the feed blade 205b can protrude from the supply port 103. At the same time, it may be formed in a shape capable of conveying toner in the axial direction of the rotation shaft 201 outside the storage chamber AR. For example, as shown in FIG. 7 (a), the tip 206a of the feed blade 206 is formed in a tapered shape that gradually narrows toward the center of the tip, and is configured to protrude from the supply port 103. Also good. (In FIG. 7A, the illustration that the tip 206a of the feed blade 206 protrudes from the supply port 103 is omitted.) According to this, the edge of the tapered tip 206a (feed blade 206). The toner is pushed toward the return port 104 by the edge 206b which is inclined with respect to the extending direction of the toner, so that the toner can be diffused better in the developing chamber DR.

  In the embodiment, the shape of the stirring blade 204b is rectangular. However, the present invention is not limited to this, and the stirring blade 204b may be formed in a shape capable of conveying toner in the axial direction of the rotation shaft 201 inside the storage chamber AR. . For example, as shown in FIG. 7B, the stirring blade 207 may be formed in a tapered shape that gradually narrows toward the center of the tip. According to this, since the toner is pushed toward the feeding blade 205b by the tapered edge 207a (edge inclined to the extending direction of the stirring blade 207) 207a, the feeding blade 205b causes the toner to be pushed. The amount of toner to be conveyed can be increased. In this case, instead of shifting the position of the feed blade 205b and the stirring blade 204b by 180 ° in the rotation direction as in the above embodiment (see FIG. 4), as shown in FIG. It is desirable to displace the stirring blade 207 at an acute angle in the rotation direction and to arrange the stirring blade 207 on the downstream side in the rotation direction with respect to the feed blade 205b. In other words, it is desirable to dispose the stirring blade 207 with respect to the feed blade 205b at an acute angle toward the downstream side in the rotation direction. Furthermore, in other words, it is desirable to arrange the feeding blade 205b and the stirring blade 207 so that the angle between the downstream surface of the feeding blade 205b and the upstream surface of the stirring blade 207 becomes an acute angle. According to this, immediately after the toner is brought to the side of the feed blade 205b by the stirring blade 207, the toner can be fed to the developing chamber DR by the feed blade 205b, so that the toner can be circulated more favorably.

  Further, the toner can be transported in the axial direction of the rotating shaft 201 inside the storage chamber AR by changing the angle of the stirring blade instead of changing the shape of the stirring blade as described above. For example, as shown in FIG. 7 (c), a pair of stirring blades 208 are provided between the feeding blades 205b, and the surfaces of the pair of stirring blades 208 facing each other are changed from the upstream side to the downstream side (in the direction perpendicular to the paper surface). The stirring blades 208 may be arranged on the rotation shaft 201 at a predetermined angle so that they gradually approach from the front side to the back side and the tips of the pair of stirring blades 208 are separated from each other. Also by this, since the toner is pushed toward the feed blade 205b, the amount of toner conveyed by the feed blade 205b can be increased.

  In the above embodiment, the length of the feeding blade 205b is made longer than that of the stirring blade 204b so that the toner conveying force by the feeding blade 205b is larger than that of the stirring blade 204b. However, the present invention is not limited to this. . For example, as shown in FIG. 9A, instead of forming the feed blade 205b and the stirring blade 209 with the same length, the feed blade 205b may be formed of a material having higher rigidity than the stirring blade 209. According to this, since the toner conveying force by the highly rigid feed blade 205b is larger than that of the rigid stirring blade 204b, the toner can be circulated well between the developing chamber DR and the storage chamber AR, and the toner can be circulated. Can be satisfactorily dispersed in the developing chamber DR, and unevenness in image density can be suppressed.

  The rigidity of the two blades is not limited to the above-described method of changing the material. For example, the width (length in the axial direction of the rotating shaft) of the stirring blade of the same material and length as the feed blade is This can also be achieved by reducing the size of the agitating blade, or by cutting out a part of the stirring blade of the same material, size and shape as the feeding blade. For example, as shown in FIG. 9B, the toner conveying force by the feed blade 205b is also stirred by diagonally cutting off one corner of the stirring blade 210 having the same material, size and shape as the feed blade 205b. It can be larger than the wing 210. As shown in FIG. 9B, when the shape of the stirring blade 210 is tapered so as to move away from the feeding blade 205b toward the tip, the toner in the storage chamber AR is fed by the stirring blade 210. This is preferable because it is brought closer to the wing 205b side.

  In the above embodiment, the supply port 103 and the return port 104 have the same vertical position when the toner cartridge 100 is mounted on the main casing 2 (see FIG. 3), but the present invention is not limited to this. It is not something. For example, as shown in FIG. 10A, the supply port 103 may be formed above the return port 104 when the toner cartridge 100 is mounted on the main casing 2 (see FIG. 1). Good. According to this, when the toner is pushed out from the supply port 103 positioned above to the developing chamber DR, the toner naturally flows to the lower return port 104 side due to the influence of gravity. For this reason, the toner circulation can be performed more favorably.

  Further, as shown in FIG. 10B, when the toner cartridge 100 is mounted on the main casing 2 (see FIG. 1), the supply ports 108 and 109 are formed so as to become wider as they go upward. The return port 110 may be formed in a shape that becomes narrower as it goes upward. According to this, when toner is pushed out from the upper part of the supply ports 108 and 109 whose upper side is wide to the developing chamber DR, the toner naturally flows to the lower part of the return port 110 which is affected by gravity. Become. For this reason, the toner circulation can be performed more favorably. In this case, as shown in the figure, if the upper part where the supply ports 108 and 109 are wide and the lower part where the return port 110 is wide are arranged so as to overlap each other in the vertical direction, This is preferable because the toner flows well from top to bottom.

  In the embodiment, nothing is provided around the supply port 103, but the present invention is not limited to this. For example, as shown in FIG. A plate-like bulging portion 300 bulging inward may be provided on the downstream side in the moving direction of 205b. According to this, since the toner conveyed by the feed blade 205b can be prevented from escaping above the supply port 103 by the bulging portion 300, more toner is sent from the supply port 103 to the developing chamber DR. be able to. Note that the bulging portion is not limited to the plate-like bulging portion 300 as shown in FIG. 11A, and for example, as shown in FIG. 11B, a part of the cylindrical wall 101 is recessed inward. The bulging portion 301 may be formed by squeezing.

In the above embodiment, the toner cartridge 100 is used as the developer container. However, the present invention is not limited to this, and a toner cartridge and a developing cartridge may be integrated.
In the embodiment, the partition portion 101a formed as a part of the cylindrical wall 101 is employed as the partition member. However, the present invention is not limited to this, and a partition member that is separate from the tubular wall 101 is employed. May be. In this case, the supply port and the return port may be formed by disposing a plurality of partition members at a predetermined interval with respect to one horizontally long hole.

In the above-described embodiment, the developer containing body that contains positively charged toner is used. However, the present invention is not limited to this, and the developer containing body may contain a negatively charged toner.
In the above-described embodiment, the developer container that accommodates the polymerized toner is employed. However, the present invention is not limited to this, and a developer container that accommodates the pulverized toner may be employed.

  In the above embodiment, the feed blade 205b is formed with a length that is in sliding contact with the cylindrical wall 101. However, the present invention is not limited to this, and the feed blade 205b is not in sliding contact with the cylindrical wall 101. You may arrange | position so that a front-end | tip may become a position slightly away from the cylindrical wall 101. FIG. Even in this case, more toner can be fed from the supply port 103 by making the lateral width of the feed blade 205b larger than that of the supply port 103.

1 is a side sectional view showing a laser printer according to an embodiment of the present invention. FIG. 3 is a cross-sectional view illustrating a detailed structure of a toner cartridge. FIG. 3 is a perspective view illustrating a supply port and a return port of a toner cartridge. It is the perspective view (a) which shows an agitator, and the schematic diagram (b) which shows the relationship between a feed blade, a stirring blade, a supply port, and a return port. FIG. 6 is a cross-sectional view (a) showing the flow of toner, a cross-sectional view taken along line XX in FIG. 5 (a), and a cross-sectional view taken along line YY in FIG. 5 (a). It is a schematic diagram which shows other embodiment of this invention, and is the schematic diagram (a) which shows the form which made the feed blade and the stirring blade the same as the width of a supply port and a return port, and the width of a stirring blade rather than a return port A schematic diagram (b) showing a reduced form, a schematic view (c) showing a form in which a plurality of supply ports or return ports are provided for one wing, and a mode in which the supply port and the return port are made into one hole. It is a schematic diagram (d) shown. It is a schematic diagram which shows other embodiment of this invention, and shows the form which formed the feed blade in the taper shape, and it can project from a supply port, and shows the form which formed the stirring blade in the taper shape. It is a schematic diagram (b) and the schematic diagram (c) which shows the form which changed the attachment angle of the stirring blade. It is a perspective view which shows the form arrange | positioned so that a feed blade and a stirring blade may be shifted by the angle which becomes an acute angle in a rotation direction, and a stirring blade may become the downstream of a rotation direction with respect to a feed blade. It is a schematic diagram which shows other embodiment of this invention, and is the schematic diagram (a) which shows the form which formed the feed blade with the material whose rigidity is larger than a stirring blade, and stirring with the same material, a magnitude | size, and a shape as a feed blade It is a schematic diagram (b) which shows the form which cut off the corner | angular part of the one side of a wing diagonally. It is a schematic diagram which shows other embodiment of this invention, and is formed in the schematic diagram (a) which shows the form which a supply port is located above a return port, and the shape which becomes wide as a supply port goes upwards And it is a schematic diagram (b) which shows the form formed in the shape which becomes narrow as a return port goes upwards. The perspective view (a) which shows the form which provided the plate-shaped bulging part which bulges inward in the downstream of the movement direction of a feeding blade among the circumference | surroundings of a supply port, and the perspective view which shows the modification of a bulging part FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser printer 2 Main body casing 17 Process cartridge 28 Developing cartridge 100 Toner cartridge 101 Cylindrical wall 102 End wall 101a Partition part 103 Supply port 104 Return port 200 Agitator 201 Rotating shaft 202 Stirring blade support 203 Feeding blade support 204 Stirring blade connection Body 204a fixed portion 204b stirring blade 205 feed blade coupling body 205a fixed portion 205b feed blade AR storage chamber DR developing chamber

Claims (10)

A developer container comprising a storage chamber for storing a developer, and an agitator that rotates in the storage chamber and stirs the developer,
The agitator is
A rotating shaft rotatably held on a wall forming the storage chamber;
A feed blade extending from the inside to the outside in the radial direction of the rotating shaft;
A stirring blade disposed at a position shifted from the feeding blade in the axial direction of the rotating shaft, and extending from the inner side to the outer side in the radial direction of the rotating shaft;
On the wall forming the storage chamber,
A supply port arranged at a position overlapping the feed blade in the radial direction of the rotary shaft, and supplying the developer to the outside;
The stirring blade and the rotating shaft are arranged at positions overlapping in the radial direction, and a return port that allows the developer to return from the outside is formed.
The feeding blade is configured such that a distance from the rotating shaft to the tip of the feeding blade is longer than a distance from the rotating shaft to the tip of the stirring blade, and with respect to the stirring blade in the rotation direction of the rotating shaft. A developer container, wherein the developer container is arranged in a staggered manner. A developer container comprising a storage chamber for storing a developer, and an agitator that rotates in the storage chamber and stirs the developer,
The agitator is
A rotating shaft rotatably held on a wall forming the storage chamber;
A feed blade extending from the inside to the outside in the radial direction of the rotating shaft;
A stirring blade disposed at a position displaced from the feed blade in the axial direction of the rotation shaft, and extending from the inside to the outside of the rotation shaft;
On the wall forming the storage chamber,
A supply port arranged at a position overlapping the feed blade in the radial direction of the rotary shaft, and supplying the developer to the outside;
The stirring blade and the rotating shaft are arranged at positions overlapping in the radial direction, and a return port that allows the developer to return from the outside is formed.
The developer container according to claim 1, wherein the feed blade has a rigidity higher than that of the stirring blade, and is arranged so as to be shifted from the stirring blade in a rotation direction of the rotation shaft.   The agitating blade is formed in a shape capable of transporting the developer in the axial direction of the rotation shaft in the storage chamber, or arranged at an angle capable of transporting the developer in the axial direction of the rotation shaft in the storage chamber. The developer container according to claim 1, wherein the developer container is provided.   The tip of the feeding blade can project from the supply port, and is formed in a shape capable of transporting the developer in the axial direction of the rotating shaft outside the storage chamber. The developer container according to any one of claims 1 to 3. In a state where the developer container is mounted on the image forming apparatus main body,
The developer container according to claim 1, wherein the supply port is positioned above the return port.   The bulge part which bulges inward is provided in the downstream of the movement direction of the feed blade among the circumference | surroundings of the said supply port, The any one of Claims 1-5 characterized by the above-mentioned. The developer container according to 1.   The developer container according to claim 1, wherein the supply port and the return port are formed as one hole.   The developer container according to any one of claims 1 to 6, wherein a partition member is interposed between the supply port and the return port. In a state where the developer container is mounted on the image forming apparatus main body,
The supply port is formed so as to become wider toward the upper side,
The developer container according to claim 8, wherein the return port is formed to become narrower as it goes upward. The developer container according to claim 8 or 9, wherein a dimension in the axial direction of the feed blade is larger than a maximum dimension in the axial direction of the supply port.

Images