JP5471220B2 - Developing device and image forming apparatus - Google Patents

Description

  The present invention relates to a developing device and an image forming apparatus, and more particularly to a stirring mechanism for a two-component developer.

  In an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a printing machine, an electrostatic latent image formed on a photosensitive member as a latent image carrier is subjected to visible image processing by a developing device, and the visible image is converted into a sheet. A recording output can be obtained by transferring to the above.

  As a developer used for development, there is a two-component developer obtained by mixing a toner and a carrier in addition to a one-component developer containing only a magnetic or non-magnetic toner.

  The two-component developer is composed of a toner and a carrier that carries the toner, and the toner can be electrostatically attracted to the electrostatic latent image on the photosensitive member by charging the toner by a frictional charging effect that occurs during stirring and mixing. It is said.

  The developing device includes a developing sleeve for supplying a developer toward the electrostatic latent image on the photosensitive member by causing the developer to rise on the peripheral surface by magnetic force, and an agitation for supplying the developer mixed with stirring to the developing sleeve. A configuration including a sleeve is known, and a developer in which toner is consumed for visible image processing of an electrostatic latent image on a photoreceptor is collected by a developing device.

  On the other hand, the toner contained in the developer is an object to be replenished because the image density decreases when consumed. At the time of replenishment, the upper part of the conveying screw provided with a screw auger as a stirring sleeve or the end in the axial direction. It may be replenished while being poured from the section.

  The toner is replenished by controlling the amount of rotation of a replenishing member that feeds out the toner stored in the toner replenishing portion in accordance with the detection result of the developer concentration by a detecting means such as a toner concentration sensor.

  In order to obtain a stable image quality, it is important that the replenished toner is stirred and mixed to be maintained at a predetermined density and charge amount before being subjected to development.

  Conventionally, the toner to be replenished is stirred and mixed with the developer, and the toner and carrier are stirred and mixed by moving the replenishing toner while rotating the spiral blade in the replenishment section provided in the developing tank. The structure to be made is proposed (for example, patent document 1).

  In Patent Document 1, a spiral blade having a rotation axis parallel to the inner wall surface of the hopper is provided in a hopper constituting the developer replenishing section, and the spiral blade is rotated, and the rotation axis is based on the cross-sectional center of the hopper. The structure which rotates in the inside is disclosed.

  In this configuration, when the spiral blade rotates and revolves in the hopper, it can be combined with conveying the developer to be dropped toward the dropping port of the developer replenishing portion in a lifting direction and natural falling. The stirring and mixing rate can be increased more than when it falls naturally.

However, in the configuration disclosed in the patent document, the developer positioned on the revolution trajectory of the spiral blade is merely stirred and mixed, and it is difficult to efficiently and uniformly mix all of the developer present in the hopper.
In addition, the combination of the rotation and revolution of the spiral blades complicates the drive mechanism, and further requires a space for obtaining the revolution trajectory. The agent replenishing part requires an extra space, and as a result, the size of the apparatus cannot be denied.

  In view of the problems in the conventional developing device, the object of the present invention is to enable efficient stirring and mixing of the developer circulating in the developing device in a short time without causing an increase in the size of the device. Another object of the present invention is to provide a developing device and an image forming apparatus having a configuration capable of providing an appropriate toner concentration and charge amount without causing stress on the developer.

In order to achieve this object, the present invention has the following configuration.
(1) A developing device capable of supplying a developer that performs visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier,
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communicating part is provided with an agitation and mixing part including an agitation member having a plurality of linear parts spaced apart from each other at least on the side where the developer moves from the supply side conveyance space toward the supply side space. ,
The developing device according to claim 1, wherein the agitating member is set in a direction that prevents movement of the developer in the communication portion as a rotation direction thereof .
(2) A developing device capable of supplying a developer that performs a visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier ,
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion includes a stirring member configured such that a plurality of linear portions are spaced from each other at least on the communication portion on the side where the developer moves from the supply-side transport space toward the supply-side space. A stirring and mixing unit is provided;
The developing device , wherein the stirring member is set so that a passage area of the developer passing between the linear portions from the rotation center toward the outside increases .
(3) A developing device capable of supplying a developer that performs visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier,
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion includes a stirring member configured such that a plurality of linear portions are spaced from each other at least on the communication portion on the side where the developer moves from the supply-side transport space toward the supply-side space. A stirring and mixing unit is provided;
The developing device, wherein the agitating member includes a plurality of developer passage portions along a circumferential direction, and the extending directions of the linear portions at adjacent developer passage portions are orthogonal to each other.
(4) A developing device capable of supplying a developer that performs visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier ,
A conveying screw that is provided in the supply-side conveying space and the recovery-side space and can be conveyed while stirring and mixing the developer ;
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion includes a stirring member configured such that a plurality of linear portions are spaced from each other at least on the communication portion on the side where the developer moves from the supply-side transport space toward the supply-side space. A stirring and mixing unit is provided;
Before SL agitating member is supported by a separate rotary shaft and the rotary shaft and the rotary shaft integrally or conveying screw of the conveyor screw,
The rotating shaft of the stirring member provided separately from the rotating shaft of the conveying screw is supported by a partition portion that partitions the both spaces and is provided in parallel with the axis of the rotating shaft of the conveying screw, and the stirring member is A developing device characterized in that the extending direction of the linear portion is provided in parallel to the axial direction of the conveying screw .
(5) A developing device capable of supplying a developer that performs a visible image processing on the electrostatic latent image formed on the latent image carrier with a developer composed of toner and carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier,
A conveying screw that is provided in the supply-side conveying space and the recovery-side space and can be conveyed while stirring and mixing the developer;
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion includes a stirring member configured such that a plurality of linear portions are spaced from each other at least on the communication portion on the side where the developer moves from the supply-side transport space toward the supply-side space. A stirring and mixing unit is provided;
The stirring member is supported by a rotating shaft that is integral with the rotating shaft of the conveying screw or different from the rotating shaft of the conveying screw,
The rotating shaft of the stirring member provided separately from the rotating shaft of the conveying screw is set in an axial direction perpendicular to the axis of the rotating shaft of the conveying screw, and the stirring member is in the axial direction perpendicular to the rotating shaft. The developing device is characterized in that the extending direction of the linear portion is set in parallel with the developing device.
(6) A developing device capable of supplying a developer that performs a visible image processing on the electrostatic latent image formed on the latent image carrier with a developer including a toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier,
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion is provided at a position where the developer flows down from the collection side conveyance space toward the supply side conveyance space, and is larger than the total volume of the supply side conveyance space and the collection side conveyance space configured by the partition portion. A developing device characterized in that a part of a developer having a large volume and moving through a communicating portion is retained .
(7) The communication portion is provided with a stirring member having a rotating shaft having an axial direction in a direction orthogonal to the axis of the conveying screw, and the axial direction of the rotating shaft of the stirring member is relative to the vertical direction. (4) or (5), wherein a part of the stirring member is located at a position inclined at an angle, and the developer stays in the direction of gravity due to the inclination of the rotation shaft. Development device.
(8) The developing device according to (7), wherein the stirring member has a rotational direction having a rotational component in a direction of lifting the developer staying in the gravity direction .
(9) An image forming apparatus using the developing device according to any one of (1) to (8).
(10) The image forming apparatus according to (9), characterized in that a developer supply transport space and a recovery transport space in the developing device are provided in a horizontal direction.
(11) The image forming apparatus according to (9), wherein a developer supply and collection space and a recovery and conveyance space in the developing device are provided in a vertical direction.
(12) The image forming apparatus according to (11), wherein the supply conveyance space is located on the upper side or the lower side in the vertical direction, and the collection conveyance space is located on the lower side or the upper side in the vertical direction.
(13) The communication portion in which the developer moves at least from the collection side conveyance space toward the supply side conveyance space in the collection side conveyance space in the developing device in the movement direction of the developer moving toward the inside of the communication portion. The image forming apparatus according to any one of (9) to (12), wherein a toner replenishing section is provided on the upstream side.

  According to the present invention, since the stirrer is provided in the communicating portion that communicates between the two spaces, provided in the partition that partitions the supply-side transport space and the collection-side transport space in the developing device, the stirrer is provided outside the developing device. Unlike the case where the mixing unit is provided, the configuration contributing to development can be reduced in size.

  In addition, the stirring member provided in the communication portion moves in the developer by mixing the developer passing and the developer moved in a mixed manner using a configuration including a linear portion having a developer passage portion. As a result, the stirring and mixing are performed satisfactorily, so that the toner concentration can be lowered and the charged state can be improved in a short time during the process of moving from the collection unit to the supply unit.

1 is a schematic diagram illustrating a configuration of a developing device according to an embodiment of the present invention. It is a schematic diagram for demonstrating the principle structure of the stirring member used for the image development apparatus shown in FIG. 3 is a graph showing a dispersion state of a developer when the stirring member shown in FIG. 2 is used. It is a figure which shows the shape used for the linear part of the stirring member shown in FIG. It is sectional drawing of the shape used for the linear part of the stirring member shown in FIG. It is a schematic diagram which shows the modification regarding the structure of the stirring member shown in FIG. It is a schematic diagram which shows the partial modification of the stirring member shown in FIG. It is a schematic diagram which shows the other modification of the stirring member shown in FIG. It is a schematic diagram which shows another modification of the stirring member shown in FIG. It is a schematic diagram which shows the structure of the developing device by another Example of this invention. FIG. 11 is a schematic diagram illustrating a partial modification of the developing device illustrated in FIG. 10. It is a schematic diagram which shows the other modification of the image development apparatus shown in FIG. FIG. 13 is a schematic diagram illustrating a partial modification of the developing device illustrated in FIG. 12. It is a schematic diagram which shows the structure of the developing device by the other Example of this invention. FIG. 15 is a schematic diagram illustrating a configuration for use in an experiment on a dispersion state (mixing degree) of a developer according to the configuration illustrated in FIG. 14. It is a graph which shows the experimental result which makes object the structure shown to FIG. 15 (A) and (B). 16 is a graph showing experimental results for the configuration shown in FIG. FIG. 15 is a graph showing a result of an experiment regarding a change in toner density targeting the configuration shown in FIG. 14. FIG. It is a graph which shows the experimental result which makes object the structure shown in FIG. 1 is a schematic diagram for explaining a configuration of an image forming apparatus to which a developing device according to the present invention is applied.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
The feature of the present embodiment is that the developer that moves between the supply-side transport space and the collection-side transport space by being partitioned by the partition in the developing tank moves through the communication portion that is configured by the lack of the partition. Ru near points so as to mix stirring.

  1A is a cross-sectional view showing a state viewed from a direction perpendicular to the axial direction of the conveying screw provided in the developing device. The developing device shown in FIG. 1 includes a casing 10 as a main component. ing.

The inside of the casing 10 is partitioned by a partition member 10A, and one of the partitioned spaces is used as a supply-side transport space 10B that supplies developer to a developing roller 20 that is used as a developer carrier. The other one is used as a developer collecting side conveyance space 10 </ b> C from the developing roller 20.
In the developing device shown in FIG. 1 (for convenience, reference numeral 10 used for the casing may be used), as shown in FIG. 1B, the supply-side transport space 10B and the collection-side transport space 10C are horizontally aligned. It is provided to be located.

  In each space, conveying screws 21 and 22 are arranged in parallel in the axial direction, and the moving direction of the developer in the space is opposite to each other by setting the lead direction or the rotation direction of the screw to be opposite. Is set to a relationship.

  Communication portions 10E and 10E ′ communicating with each other by the lacking portions 10A1 and 10A2 of the partition member 10A are formed at both ends in the axial direction of the transport screws 21 and 22, and the developer transported by the transport screws 21 and 22 is received. Passed and can be circulated as shown by the one-dotted line.

  In each space where the conveying screws 21 and 22 are arranged, in the supply-side conveying space 10B, the developer carried on the developing roller 20 is developed after the layer thickness is regulated by the doctor blade 25 and the carrying amount is regulated. In the collection-side transport space 10C, the developer collected from the developing roller 20 after being developed is introduced from the communication unit 10E and stirred and mixed, and then again supplied to the supply side via the communication unit 10E ′. It moves to the transfer space. The developer supplied to the developing roller 20 is electrostatically attached to the electrostatic latent image formed on the photosensitive drum 30 which is a latent image carrier and is subjected to visible image processing.

  Among the above-described spaces, the collection-side transport space 10C has an upstream side of the communication portion 10E where the developer moves from the collection-side transport space 10C toward the supply-side transport space 10B in the developer movement direction, in particular, A toner replenishing port 10F as a new toner replenishing portion is provided in the vicinity of the upstream side. In this embodiment, the toner replenishing unit has the same conditions as the communication unit 10E described above in the developer moving direction (at least the upstream side of the communication unit moving from the collection-side transport space 10C to the supply-side transport space 10B). Further, the communication part 10E ′ is also provided as a target (indicated by reference numeral 10F ′).

  Of the communication portions 10E and 10E ′, at least the communication portion 10E on the side where the developer moves from the collection-side conveyance space 10C toward the supply-side conveyance space 10B is configured by a linear portion as a developer passage portion. A stirring member 11 is provided. In the embodiment shown in FIG. 1, the stirring member 11 'is provided not only in one communicating portion 10E but also in the other communicating portion 10E'.

  FIG. 2 is a schematic diagram for explaining the principle structure of the stirring member. In FIG. 2, the stirring member (for the sake of convenience, reference numeral 21 is used, but the reference numeral 22 also has the same configuration). As shown in FIG. 2 (A), it is provided with a stirring portion extending in the radial direction at a plurality of locations along the circumferential direction, and the stirring portion is shown in FIG. 2 (B). As described above, the plurality of linear portions are formed at intervals.

The gap between the linear portions is a developer passage portion, and pushes against the developer passing between the linear portions and the linear portion by rotating in a direction that prevents the movement of the developer moving at the communication portion. The developer to be moved is mixed.
The developer passing between the linear portions and the developer pushed and moved by the linear portions are in a state where the moving speeds are different from each other, causing friction between the developers, stirring and mixing, and friction charging. be able to.

  If the moving speed becomes different, the moving speed of the developer into the space changes, and the dispersibility of the developer in the space seems to be different from the initial condition. It has been confirmed by experiments that it has a positive effect on the dispersibility of the developer.

  FIG. 3 is a graph showing the results of an experiment regarding the dispersibility of the developer according to the principle structure shown in FIG. 2 and the toner when replenished.

In FIG. 3, the horizontal axis indicates the dispersion state in the axial direction of the transport screw 21 located in the supply-side transport space 10B, and the vertical axis indicates the amount of dispersion.
As shown in FIG. 3, it can be seen that by providing the stirring member in the communicating portion, the amount and state of dispersion of the developer moving to the supply-side transport space 10B are balanced in the axial direction of the transport screw 21. This is considered to be caused by the leveling of the developer due to the difference in the moving speed of the developer by the stirring member at the communicating portion where the developer is concentrated.

On the other hand, the above-described configuration can obtain good results even in the stirring and mixing of the replenishing toner, and can prevent deterioration of the charging characteristics of the toner. The reason is as follows.
Since the toner has a specific gravity smaller than that of the developer, if a large amount of replenishment is performed at once, the toner may float on the developer powder surface immediately after the replenishment and may exist in an unmixed state. Unmixed toner easily scatters, resulting in background staining and image quality deterioration.

  Therefore, in this embodiment, since the developer can be pushed up by the linear portion that rotates in a direction that hinders the movement of the developer, when the pushed up developer falls, the developer is poured from above the unmixed toner. Therefore, the mixing with the replenished toner is promoted, and the opportunity for the unmixed toner to be supplied to the developing roller can be reduced.

  Regarding the stirring and mixing of the toner and the developer at the time of toner replenishment, the installation position of the toner replenishment unit also brings about a good result. That is, as shown in FIG. 1, the toner replenished toner is provided by providing the toner replenishing port 10 </ b> F in the vicinity of the upstream side in the direction in which the developer moves from the collection-side transport space to the supply-side transport space in the communication portion. Can be immediately stirred in the communicating portion 10E and taken into the developer. Thereby, the unmixed toner is not left as it is, and problems such as toner scattering can be solved. The same operation can be obtained in the other toner replenishing portion 10F 'provided corresponding to the communicating portion.

On the other hand, the following conditions are set for the stirring members 11 and 11 ′ with respect to the linear portions and the developer passage portion between the linear portions.
Since the linear portion needs to have an area capable of pushing and moving the developer and toner, the width of the linear portion, that is, the dimension perpendicular to the extending direction of the linear portion is 0.3. ~ 3mm is selected.

Further, when the developer passage portion has a rotation speed V and the area of the developer passage portion S,
V x S = K
However, the condition that K: means a certain amount is set.

Such a condition, particularly the condition for the developer passage portion, is caused by the fact that the agitating members 11 and 11 ′ are rotating members. In other words, the linear velocity and torque on the outer side of the rotating member increase with respect to the rotation center. For this reason, the stress with respect to the developer located in the outer peripheral part of the stirring members 11 and 11 ′ increases.
Therefore, in this embodiment, the developer passage amount in the radial direction from the rotation center according to the rotation speed from the rotation center is equalized to prevent an increase in stress on the developer at the outer peripheral portion. The area of the developer passage part can also be adjusted by adjusting the width of the linear part. A configuration that satisfies such a condition can be realized, for example, by increasing the area of the developer passage portion as it approaches the outer periphery.

The shape shown in FIGS. 4 and 5 can be selected as the shape or cross-sectional shape of the linear portion in the extending direction.
FIG. 4 is a diagram showing the shape of the linear portion in the extending direction, and is a straight line (FIG. 4A, a shape obtained by bending a straight line at a predetermined angle (FIG. 4B)), and a curve having a radius of curvature. The shape (FIG. 4C) and the like can be selected, and by selecting these shapes, the range in which the developer is pushed can be diversified, and thereby, the stirring and mixing property of the developer can be improved.

  Next, 5 is a figure which shows the cross-sectional shape of a linear part, circular FIG. 5 (A), an ellipse (FIG. 5 (B)), and the rectangle (square, rectangle) which rounded the angle (FIG. 5 (C)) , Triangles (FIG. 5 (DS)), squares (FIG. 5 (E)), rectangles (FIG. 5 (F)), polygons (FIG. 5 (G)), or semicircles (FIG. 5 (H)) ), A shape with a partial depression (FIG. 5I) or the like is selected.

Depending on the surface shape on the upstream side in the rotation direction, the amount of developer to be pushed out (the amount of accumulation) changes, whereby the agitation performance changes. For this reason, in consideration of the wire diameter and the distance between the linear portions, the shape of the upstream surface can be selected each time with good stirring efficiency.
Further, by eliminating the edge, it is possible to reduce a local pressure increase on the developer and to prevent the developer from being deteriorated. In particular, in order to reduce the stress applied to the developer, it is desirable to select a circle or a semicircle.

  As the material of the linear member, metal, resin, or those that can be replaced are selected in consideration of strength, etc., and as processing methods, assembly by welding or adhesion, etc., from a single plate to a linear member A method of punching a portion other than the corresponding portion or molding is used.

  In the above-described conditions for the developer passage portion, the interval distance between the linear portions must be at least the interval dimension that allows the carrier contained in the developer to pass. In the present embodiment, this will be described later. In consideration of the size of the toner and carrier of the developer to be developed, it is set to 0.5 to 10 mm. This prevents an increase in stress on the developer due to a phenomenon similar to the clogging phenomenon that occurs when the interval distance is small, and reduces the stirring mixing rate and developer fluidity that occur when the interval distance is too large. Deterioration can be prevented.

  In this embodiment, when a two-component developer containing a carrier of 35 μm and a toner of about 5 μm is used, if the width of the linear member is about 0.3 to 3 mm as described above, the distance dimension described above is 2 to 5 mm. It was confirmed by experiment that it was optimal to set the degree.

FIG. 6 is a diagram illustrating the configuration of the stirring section in the stirring member 11 using the shape of the linear section illustrated in FIG. 4 and other shapes.
6A shows a stirring member made up of a linear member of a broken line, FIG. 6B shows a stirring member made up of a curve, and FIG. 6C shows a stirring made of crossing linear linear members. FIG. 6D shows a combination of a plurality of circular linear members and linear stirring members.

  In this way, it is possible to create various agitation shapes depending on how the linear members are combined. Therefore, considering the rotation speed of the agitation member, the angle θ of the agitation shaft, the available agitation space, etc., the optimum agitation is required each time. It can be shaped.

  In particular, in the configuration shown in FIG. 6E, the width of the linear portion is narrowed and the gap interval is widened to increase the area of the developer passage portion from the rotation center toward the outer periphery. By adopting such a configuration, an increase in stress on the developer on the outer peripheral side due to a difference in linear velocity and torque between the rotation center side and the outer peripheral side that occurs when the stirring member rotates is reduced and rotation is performed. Stirability on the center side and the outer peripheral side can be made uniform.

As illustrated in FIG. 2, the stirring members 11 and 11 ′ include a plurality of stirring portions along the circumferential direction. Therefore, in this embodiment, it is also possible to vary the form of the developer passage portion in each stirring portion along the circumferential direction.
FIG. 7 shows an embodiment in this case. In FIG. 7, paddle-shaped stirring portions (for convenience, indicated by reference numerals 11A and 11B) provided in the circumferential direction of the stirring member (for convenience, reference numeral 11 is used). ) Has a relationship in which the developer passage portions in the adjacent stirring portions have the extension directions of the linear portions orthogonal to each other as shown in FIGS. 7B and 7C.

  In the configuration of such an embodiment, when the developer moves, one stirring unit passes through the developer passing unit, and the other stirring unit is pushed and moved by the linear unit. Therefore, the mixing and mixing property of the developer can be enhanced by utilizing the difference in moving speed caused by this movement.

Moreover, as a form of a stirring part, it is also possible to use the structure shown in FIG.
In FIG. 8, a brush is used as the linear portion. A large number of brushes are provided in the circumferential direction along the axial direction of the rotation shaft. In this configuration, unlike the agitation unit using a paddle, the developer can be agitated and mixed in the axial direction and the circumferential direction.

  FIG. 9 is an application example of the configuration shown in FIG. 8, and a three-time configuration in which wires constituting a plurality of linear portions are installed along the circumferential direction of a pair of ring members provided on the rotating shaft. It has. With this configuration, it can be installed in a limited space and can be efficiently stirred and mixed.

  In the embodiment as described above, since the agitation / mixing unit provided with the agitation member is provided in the existing communication part configured in the developing device, there is no need to provide the agitation / mixing unit outside the developing device, The structure used can be reduced in size. Moreover, since the stirring member can equalize the state of passage of the developer when rotating between the rotation center side and the outer peripheral side, a uniform toner concentration and charge amount can be obtained for the developer moving through the communicating portion. Can be set.

  As a configuration in which the stirring member is provided integrally with the rotation shaft of the transport screw, a configuration in which the supply-side transport space and the recovery-side transport space in the developing device are arranged in the vertical direction can be targeted.

Figure 10 shows the configuration of the developing apparatus in this case, in the drawing, the developing apparatus (for convenience, denoted by reference numeral 30 to indicate the casing), the rotation shaft of the agitating member provided in the communicating portion The structure provided separately from the rotating shaft of the stirring screw is used .
That is, unlike the case shown in FIG. 1, the supply-side transfer space 30E and the collection-side transfer space 30E ′ are arranged in the vertical direction, and the supply-side transfer space 30E is located on the upper side, and the lower side The collection-side transport space 30E ′ is located in FIG.

  In the developing device 30 having this configuration, the developer transported and pumped up by the transport screw 32 in the supply-side transport space 30E moves to the developing roller 31 after the layer thickness is defined by the doctor blade 34.

  After the development, the developer remaining on the developing roller 31 moves toward the recovery side transport space 30E 'and is stirred and mixed by the transport screw 33 located in the recovery side space 30E'. In FIG. 10, the movement state of the developer from the developing roller 31 toward the collection-side transport space is indicated by a one-dot chain line.

  The interior of the developing device 30 is partitioned by the partition member 35 into the supply-side transport space 30E and the collection-side transport space 30E ′ described above, and the end of the partition member 35 in the extending direction is the same as that shown in FIG. The communication part 36 is provided in the.

  The developer accumulated in the communication portion 36 can be lifted toward the supply-side conveyance space 30E located at the upper portion of the rotation axis of the conveyance screw 33 located in the collection-side conveyance space 30E ′ in the communication portion 36. A stirring member 37 capable of rotating is provided. In the stirring member 37, the extending direction of the linear portion is parallel to the axial direction of the conveying screw.

The movement state of the developer in this configuration is as follows.
In the supply-side transport space 30E, the developer is transported from the front side to the back side in FIG. 10A, and a part of the developer is supplied to the developing roller 31 in the transport process. It flows down toward the collection-side transport space 30E ′ via the communication portion located on the back side of the sheet of FIG.

  The developer remaining on the developing roller 31 is moved to the collection-side transport space 30E ′ side by a repulsive magnetic field from a repulsive magnetic pole built in the roller 31, and is moved to the far side in front of the paper in FIG. 10A by the transport screw 33. It is transported and moves toward the supply-side transport space 30E by accumulating and rising at the communicating portion located on the front side of the sheet.

  Since the stirring member 37 is disposed in the communicating portion (indicated by reference numeral 36 in FIG. 10B) on the front side of the sheet in FIG. 10A, it accumulates at that position in the collection-side transport space 30E ′. The developer can be moved so as to be lifted toward the supply-side transport space 30E.

  Since the agitating member 37 is provided at a position where the developer moves from the collection-side conveyance space 30E ′ toward the supply-side conveyance space 30E, similarly to the configuration shown in FIG. 1, in the collection-side conveyance space 30E ′ The developer that has been conveyed and deposited is agitated and mixed in the course of the developer rising. Accordingly, the developer can be moved to the supply-side transport space 30E while preventing the developer from condensing.

  In the configuration described above, since the agitating member 37 is provided at a position where the developer moves from the collection-side conveyance space 30E ′ toward the supply-side conveyance space 30E, after development that has moved to the collection-side conveyance space 30E ′. In addition to stirring and mixing the developer by the conveying screw 33, stirring and mixing by the stirring member 37 is further performed. As a result, even when the developer aggregates in the vicinity of the communicating portion corresponding to the final process position in the developer conveyance process by the conveyance screw 33, the agitation member 36 moves in the lifting direction, thereby developing by aggregation. The toner concentration and the charge amount can be optimized while preventing an increase in the stress of the agent.

FIG. 11 is a diagram illustrating a case where the rotation shaft of the stirring member provided in the communication portion is provided separately from the rotation shaft of the conveying screw.
In FIG. 11, the stirring member (indicated by reference numeral 37 used in FIG. 10 for convenience) includes a rotating shaft 37 </ b> A in which both ends in the axial direction are indicated by the partition member and the casing wall.

  The rotation shaft 37A is provided in parallel with the rotation axis of the conveying screws 32 and 33, and is driven by a driving source provided independently of the driving source for the conveying screws 32 and 33. The drive source for the stirring member 37 is configured to have its own rotational speed and rotational speed.

  In the stirring member 37, the extending direction of the linear portion is parallel to the axial direction of the conveying screws 32 and 33.

  In such an embodiment, as in the case shown in FIG. 10, the developer deposited on the communication portion 36 is agitated and mixed, and the developer is lifted from the recovery side conveyance space 30E ′ toward the supply side conveyance space 30E. Can be moved.

  In particular, in this embodiment, since the agitating member 37 is rotationally driven independently of the conveying screws 32 and 33, the toner concentration and the charge amount are optimized by variously controlling the agitating and mixing state in the communicating portion 36. Is possible. In other words, the toner concentration and the charge amount of the developer depend on the stirring and mixing property of the replenished toner and the developer or the stirring and mixing property of the circulating developer.

  Therefore, in this embodiment, when a large amount of toner is replenished due to a change in the image area ratio or the like, the rotational speed of the agitating member 37 is set to be higher than the previously set speed, When replenishment is not performed much, the rotation speed of the stirring member 37 can be set to a decreasing tendency including a stop. As a result, stirring and mixing properties corresponding to the amount of toner to be replenished can be obtained, and the toner concentration and charge amount can be optimized regardless of the toner replenishment state.

On the other hand, FIG. 12 shows a modified example in which the rotating shaft of the stirring member is provided separately from the rotating shaft of the conveying screw.
In the drawing, the rotation shaft 37 </ b> A of the stirring member 37 is set to have a relationship in which the axial direction is perpendicular to the axial direction of the rotation shafts of the conveying screws 32 and 33. The rotating shaft 37A of the stirring member 37 is provided at a position that does not interfere with the rotating shafts of the conveying screws 32 and 33. The stirring member 37 is configured such that the extending direction of the linear portion is set in parallel to the axial direction of the rotation shaft.

  In the present embodiment, since the rotation direction of the stirring member 37 is a direction perpendicular to the rotation direction of the conveying screw, the stirring member 37 accumulates on the communication portion 36 and rises to rise from the recovery-side conveying space 30E ′ to the supply-side conveying space 30E. The developer moving toward the surface can be sheared. As a result, when the developer moves through the communicating portion, the developer is sheared in a direction different from the moving direction, thereby generating a complicated flow. As a result, the stirring and mixing property of the developer moving through the communication portion 36 is improved. Since shearing can be performed without stopping the movement of the developer, stirring and mixing can be performed without causing stress such as aggregation of the developer.

  FIG. 13 shows a further modification when the rotating shaft 37A of the stirring member 37 is provided separately from the rotating shafts of the conveying screws 32 and 33, as in the case shown in FIG. A configuration for assisting the movement of the developer at the communication portion is used.

In FIG. 13, a spiral member 38 having an outer diameter smaller than the outer diameter of the stirring member 37 is integrated with the rotating shaft 37 </ b> A of the stirring member 37.
The spiral member 38 has blades configured to allow the developer to move from the collection-side transport space 30E ′ toward the supply-side transport space 30E. As a configuration when the spiral member 38 is provided together with the stirring member 37, for example, the configuration shown in FIG. 9 is used, and a rotating shaft that indicates the spiral member 38 is inserted in the center between the end plates on which the wires are installed. This prevents the stirring member 37 and the spiral member 38 from interfering with each other.

In the present embodiment, the spiral member 38 rotates together with the stirring member 37 shown in FIG.
In FIG. 13, the spiral member 38 shears and stirs and mixes the developer that moves in the upward direction at the communicating portion 36 as described in FIG. 12 by rotating, while the spiral member 38 is positioned at the communicating portion. The developer to be raised is raised. When a part of the developer that has risen falls from the raised position, the developer rises again by the spiral member 38 and is agitated by repeating this operation.

  In the present embodiment, by providing the spiral member 38, the developer can be circulated by repeating the rising and dropping of the developer in the communication portion 36. Thereby, stirring property can be improved, preventing a developer from condensing.

Then, provided the residence section for storing the developer in the communication portion, it describes another embodiment for mixing and stirring the developer staying.

  FIG. 14 is a diagram showing a developing device according to the above-described embodiment. The developing device shown in FIG. 14 (for convenience, the reference numeral 40 indicating the casing in FIG. 14 is used) is similar to the case shown in FIG. Although the supply-side transport space 40E and the collection-side transport space 40E ′ are arranged in the vertical direction, the arrangement of the spaces is different from the case shown in FIG. That is, in FIG. 14, the supply-side transport space 40E is located on the lower side in the vertical direction, and the collection-side transport space 40E 'is located on the upper side in the vertical direction.

  In the developing device 40 in this configuration, the developer that is transported and pumped up by a transport screw (indicated by the reference numeral 32 used in FIG. 10) 32 in the supply-side transport space 40E is a doctor blade (for convenience, reference numerals used in FIG. 10). 34), the developer moves to the developing roller 31 after the layer thickness is defined.

After the development, the developer remaining on the developing roller 31 moves toward the collection-side transport space 40E ′ and is agitated by a transport screw (shown by reference numeral 33 used in FIG. 10 for convenience) located in the collection-side space 40E ′. Mixed.
The interior of the developing device 40 is partitioned into the supply-side transport space 40E and the collection-side transport space 30E ′ described above by a partition member (denoted by reference numeral 35 used in FIG. 10 for convenience), and the end of the partition member 35 in the extending direction As in the case shown in FIG. 1, the part is provided with a communication part (indicated by reference numeral 36 in FIG. 10 for convenience).

The movement of the developer in the developing device having such a configuration is as follows.
In the supply-side conveyance space 40E, the developer is conveyed from the front side to the rear side in FIG. 14A, and a part of the developer is supplied to the developing roller 31 in the conveyance process. The developer that has moved in the supply-side transport space 40E including the developer flying from the developing roller 31 due to the repulsive magnetic field of the developing roller 31 is collected on the collection side via the communication portion located on the back side of the paper surface of FIG. As the developer rises and rises toward the conveyance space 40E ′, it is introduced into the collection-side conveyance space 40E ′.

  The developer introduced into the collection-side transport space 40E 'flows down toward the supply-side transport space 40E by the transport screw 33 through the communication portion 36 located on the front side of the sheet of FIG. In FIG. 14, the movement state of the developer with respect to the supply-side transport space 40E and the recovery-side transport space 40E 'with respect to the developing roller 31 is indicated by a one-dot chain line.

  The communication portion 41 shown in FIG. 14 has a volume larger than the total volume of the supply-side transport space 40E and the collection-side transport space 40E ′, and is configured as a portion that retains a part of the developer.

  In FIG. 14, when it is assumed that each space where the conveying screw is arranged enters an end portion in the axial direction of the conveying screw into the communicating portion 36, the communicating portion 36 swells in a portion below the space volume in which it enters. The volume is increased by the amount that is taken out (the part indicated by the symbol L in FIG. 14).

On the other hand, although the communicating member 36 is provided with the stirring member 41 as in the configuration described so far, the installation conditions of the stirring member 41 in the present embodiment are different from the configurations in the previous embodiments. The details will be described below.
The agitating member 41 has a configuration in which a plurality of linear portions are provided on a pair of paddles facing each other across the rotation center, and a space between the linear portions is a developer passage portion. The screws 32 and 33 are provided so as to be orthogonal to the axial direction of the rotation shaft in the plan view.

The rotating shaft 41A of the agitating member 41 is inclined such that its axial direction has an angle θ with respect to the vertical direction. The reason for this configuration is as follows.
The flow of the developer in the present embodiment is not in the state where the developer rises and rises in the communicating portion, but in the state of falling, as in the embodiments described so far. For this reason, the reason is that the developer agitation time can be sufficiently secured with respect to the developer movement time. That is, the developer is agitated by receiving the shearing force from the agitating member 411 during the drop movement, and at that time, the aggregation does not occur as in the case where the developer rises, so that the influence of stress on the developer can be reduced.

  In particular, since the rotating shaft 41 is inclined, not only stirring in the horizontal direction but also vertical stirring is performed by pushing the linear portion in the vertical direction. Thereby, even if stirring time becomes a little short, stirring property does not fall.

  In addition, when a developer storage part, that is, a so-called buffer part, is provided by tilting the rotation shaft 45 to make the volume larger than the total volume of the conveyance space, the developer present in that part is stirred by the stirring member. Can be done. That is, since the stored developer is repeatedly scooped up and dropped by the stirring member 41, the developer moves in the vertical direction and the stirring property is further improved.

  In the present embodiment, an angle close to 45 degrees is set as the inclination angle of the rotation shaft 41A. Further, since the cross-sectional shape of the portion where the developer is stored (portion indicated by L in FIG. 14) is an inverted cone, the developer can rise on the conical surface by the centrifugal force generated when the stirring member 41 rotates. As a result, it is possible to stir almost the entire longitudinal and horizontal directions of the communicating portion 36.

  In addition, regarding the volume of the communication portion, as in the embodiment shown in FIG. 14, not only the inverted conical portion is provided, but the axial direction of the rotating shaft of the stirring member is orthogonal to the rotating shaft of the conveying screw. If so, the position of the rotating shaft of the stirring member is shifted in order to prevent interference with the rotating shaft of the conveying screw, so that the volume is as much as securing the rotation locus when rotating the stirring member at the shifted position. It can be said that it will increase.

  Further, the cross-sectional shape of the communication portion 36 shown in FIG. 14, that is, the shape seen from the shaft ends of the conveying screws 32 and 33, allows the developing device to be loaded into a cartridge (indicated by reference numeral PC in FIG. 14). For this reason, the corner portion is reduced in accordance with the shape of the cartridge. In FIG. 14, the symbol FL indicates the powder level of the developer that has fallen and stored in the communication portion 36.

In the examples as described above, the present inventors obtained the results shown in FIGS. 16 to 19 that the stirrability using the stirring member was experimented.
As an experimental method for obtaining the results shown in FIGS. 16 to 19, the particles accommodated in the agitation container shown in FIG. 15 are divided into a and b and two layers (a is an upper layer and b is a lower layer), The layered particles are agitated by a linear agitation mechanism and a non-linear agitation mechanism, and the abundance ratio of the particles present in each layer of a and b by the agitation time in a certain size cell. Simulated what would be. Furthermore, based on this result, plotting was performed in FIGS. 16 and 17 using an index of degree of mixing.
As for the degree of mixing, the stirring portion is equally cut out into cells of a certain size, and the standard deviation σ of the number fraction of the particles a and b contained in each cell is obtained by the following equation.

Here, xi is the number fraction of colored particles contained in the cell i, xc is the number fraction of colored particles in the container, and N is the number of cells.
Using this, the degree of mixing is defined by the following equation.

  It can be determined that the mixing / dispersion progresses as the degree of mixing defined in this way becomes smaller and becomes uniform.

FIG. 16 shows the results obtained when the inclination angle θ of the container from the vertical direction shown in FIG.
It can be seen that as the angle of the rotation axis approaches 45 °, the degree of mixing decreases rapidly and the agitation improves. This is because the horizontal stirring is sufficiently performed at the rotation axis angle θ = 0 °, but the vertical movement of particles is not as noticeable as in the horizontal direction. I will not. As the rotation axis angle θ approaches 45 °, the movement of particles in the vertical direction becomes active as in the horizontal direction, and three-dimensional stirring is performed, resulting in a uniform stirring state as a whole.
Further, as shown in FIG. 15 (B), when the inclination is 45 °, the stirrability close to the provided conditions is obtained even in the configuration excluding the central screw provided as the stirring assisting member in the gravity direction. It can be seen from the simulation results that this is maintained. As a result, sufficient agitation is possible even in a limited agitation space (due to consideration of the axial position of the conveying screw, limitations due to miniaturization, etc.) where a spiral member (corresponding to the member denoted by reference numeral 38 in FIG. 13) cannot be provided It is possible to maintain sex.

Further, FIG. 17 shows the result of the configuration (FIG. 15C) in consideration of the axis of the conveying screw (for convenience, indicated by reference numerals 32A and 33A in FIG. 15).
In FIG. 17, it is shown that the configuration with the shaft has a faster decrease in the mixing degree and the stirrability is higher than the condition not considered depending on the presence or absence of the shaft of the conveying screw. This is because the particles (developer) are sheared by the linear stirring member 27 and the shafts 32A and 33A of the conveying screw, thereby improving the mixing stirring property.
From the above results, it can be said that the example of the present invention as shown in FIG. 14 has a very excellent mixing and stirring property.

Next, with respect to the embodiment of the present invention (θ = 50 °) shown in FIG.
Evaluation conditions / Developer: Initial toner concentration 7 wt%
-Toner replenishment amount: 0.74 g
・ Conveying screw: Outer diameter 20mm, Longitudinal length 390mm
-Conveying screw rotation speed: 600 rpm
・ Toner replenishment position: ・ Conventional conditions (comparison conditions): The most upstream side of the collecting screw
Inventive Example: Immediately before the agitation container The toner is replenished under the above conditions, and the toner density fluctuation at the upstream side of the supply side screw (corresponding to the sleeve position) is measured by the density sensor. Indicated. (Toner replenishment amount 0.74 g is a condition larger than the amount actually replenished at one time.) Under the conventional conditions, toner density fluctuation is abruptly observed after toner replenishment, and thereafter, the toner is constantly stabilized.

  On the other hand, in the inventive examples, initial fluctuations are seen, but the fluctuations are much smaller than the conventional conditions. The peak difference of fluctuation (maximum TC after replenishment−minimum TC) is 1.4% compared to the conventional one, and the inventive example is about 0.25%, which is reduced to 1/5 (TC is the toner Meaning of concentration).

  Further, the toner charge amount distribution of the embodiment shown in FIG. 1 is shown in FIG. Even under the condition immediately after replenishment, which is the toner density distribution at the maximum TC, weak charging, reverse charging, etc. are not confirmed, and are very stable. It has been found that the peak difference of density fluctuation and the charge amount distribution as described above have a correlation with the image density, and the configuration of the embodiment of the present invention has a very high image quality (compared to the conventional screw stirring method). Can be obtained.

  As described above, in this embodiment, the developer can be sufficiently mixed and stirred in a short time and with a relatively simple drive without taking up a large space. It is possible to provide stable image quality.

Next, the function and configuration of the image forming apparatus to which the developing device having the above-described configuration is applied will be described.
In FIG. 20, when a document bundle is placed on the document table 102 of the ADF 101 with the image surface facing upward and a start key on an operation unit (not shown) is pressed, the lowest document is fed by the feed roller 103 and the feed roller 103. It is fed to a predetermined position on the contact glass 105 by the feeding belt 104.

  After the image information is read by the image reading unit 106, the document on the contact glass 105 is discharged onto the paper discharge tray 108 by the feeding belt 104 and the discharge roller 107. When the document detection sensor 109 detects that the next document exists on the document table 102, the document is fed onto the contact glass 105 as described above.

  The image reading unit 106 performs line scanning on the image information of the original in the sub-scanning direction while irradiating the original on the contact glass 105 with the two lamps 128, and uses the reflected light as image data as the first mirror 129 and the second mirror. 130, the light is reflected in a predetermined direction by the third mirror 131, and sent to the CCD 133 via the lens unit 132 for reducing and forming an image.

  The image data read by the image reading unit 106 is sent to a writing unit 118 having a laser light emitting device 134, an fθ lens 135, a reflecting mirror 136, and the like via an image processing unit (not shown). An electrostatic latent image corresponding to the original image is formed on the top.

  Inside the main body 100, a photosensitive drum 1, a developing device having a casing 10, a fixing unit 121, a paper discharge unit 122, first to third paper supply devices 110, 111, 112, a vertical conveyance unit 116, and the like are arranged. Has been. The photosensitive drum 1 is uniformly charged by a charger (not shown) and then exposed to light information from the writing unit 118 to form an electrostatic latent image. The electrostatic latent image is developed by a developing device and is toner. An image is formed.

  A conveyor belt 120 is disposed below the photosensitive drum 1. The conveyance belt 120 also serves as conveyance means and transfer means for transfer paper, which is a recording medium. A transfer bias is applied from a power supply (not shown), and the transfer paper from the vertical conveyance unit 116 is conveyed at a constant speed with the photosensitive drum 1. While the toner image on the photosensitive drum 1 is transferred to the transfer paper.

  The toner image transferred to the transfer paper is fixed on the transfer paper in the fixing unit, and the transfer paper on which the image is fixed is discharged onto the paper discharge tray 123 via the paper discharge unit 122. The photosensitive drum 1 is cleaned by a cleaning unit (not shown) after the toner image is transferred, and is prepared for the next image formation.

  The paper discharge unit 122 includes a reversing unit 125 that feeds the transfer paper from the middle thereof by a pair of transport rollers 124, an image forming side transport path 126 that transports the transfer paper reversed by the reversing unit 125 to the vertical transport unit 116 side, and a reversal. A double-sided conveyance path having a paper discharge conveyance path 127 and the like for returning the transferred transfer paper to the paper discharge unit 122 again is provided. With this double-sided conveyance path, images can be formed on both sides of the transfer paper, or discharged onto the paper discharge tray 123 with the image-formed side down.

When selected, the first to third paper feeding devices 110, 111, and 112 feed transfer sheets stacked on the first tray 113, the second tray 114, and the third tray 115, respectively.
The fed transfer paper is conveyed to a position where it comes into contact with the photosensitive drum 17 by the vertical conveyance unit 116.

  In this image forming apparatus, image data from the outside is input to the writing unit 118 instead of the image data from the image processing means during the printer function, and an image is formed on the transfer paper by the image forming means.

During the facsimile function, the image data from the image reading unit 106 is transmitted to the other party by a facsimile transmission / reception unit (not shown), and the image data from the other party is received by the facsimile transmission / reception unit. As a result of the input, the image forming means operates to form an image on the transfer paper.

  In the above-described configuration, an example in which a multifunction peripheral is used as the image forming apparatus has been described. However, the image forming apparatus to which the present invention can be applied is not limited thereto, and other image forming apparatuses such as a copying apparatus, a printer, a facsimile machine, and a plotter. In addition, the present invention is applicable.

10, 30, 40 Developing device 11, 11 ′, 37, 41 Stirring member 21, 22, 32, 33 Conveying screw 10A, 35 Partition member 36 Communication portion 37A Rotating shaft of stirrer member 38 Spiral member θ Inclination angle of stirrer member

Japanese Patent No. 2939099

Claims (13)

A developing device capable of supplying a developer that performs a visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier,
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communicating part is provided with an agitation and mixing part including an agitation member having a plurality of linear parts spaced apart from each other at least on the side where the developer moves from the supply side conveyance space toward the supply side space. ,
The developing device according to claim 1, wherein the agitating member is set in a direction that prevents movement of the developer in the communication portion as a rotation direction thereof . A developing device capable of supplying a developer that performs a visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier ,
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion includes a stirring member configured such that a plurality of linear portions are spaced from each other at least on the communication portion on the side where the developer moves from the supply-side transport space toward the supply-side space. A stirring and mixing unit is provided;
The developing device , wherein the stirring member is set so that a passage area of the developer passing between the linear portions from the rotation center toward the outside increases . A developing device capable of supplying a developer that performs a visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier,
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion includes a stirring member configured such that a plurality of linear portions are spaced from each other at least on the communication portion on the side where the developer moves from the supply-side transport space toward the supply-side space. A stirring and mixing unit is provided;
The developing device, wherein the agitating member includes a plurality of developer passage portions along a circumferential direction, and the extending directions of the linear portions at adjacent developer passage portions are orthogonal to each other. A developing device capable of supplying a developer that performs a visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier ,
A conveying screw that is provided in the supply-side conveying space and the recovery-side space and can be conveyed while stirring and mixing the developer ;
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion includes a stirring member configured such that a plurality of linear portions are spaced from each other at least on the communication portion on the side where the developer moves from the supply-side transport space toward the supply-side space. A stirring and mixing unit is provided;
Before SL agitating member is supported by a separate rotary shaft and the rotary shaft and the rotary shaft integrally or conveying screw of the conveyor screw,
The rotating shaft of the stirring member provided separately from the rotating shaft of the conveying screw is supported by a partition portion that partitions the both spaces and is provided in parallel with the axis of the rotating shaft of the conveying screw, and the stirring member is A developing device characterized in that the extending direction of the linear portion is provided in parallel to the axial direction of the conveying screw . A developing device capable of supplying a developer that performs a visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier,
A conveying screw that is provided in the supply-side conveying space and the recovery-side space and can be conveyed while stirring and mixing the developer;
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion includes a stirring member configured such that a plurality of linear portions are spaced from each other at least on the communication portion on the side where the developer moves from the supply-side transport space toward the supply-side space. A stirring and mixing unit is provided;
The stirring member is supported by a rotating shaft that is integral with the rotating shaft of the conveying screw or different from the rotating shaft of the conveying screw,
The rotating shaft of the stirring member provided separately from the rotating shaft of the conveying screw is set in an axial direction perpendicular to the axis of the rotating shaft of the conveying screw, and the stirring member is in the axial direction perpendicular to the rotating shaft. The developing device is characterized in that the extending direction of the linear portion is set in parallel with the developing device. A developing device capable of supplying a developer that performs a visible image processing on an electrostatic latent image formed on a latent image carrier with a developer composed of toner and a carrier,
The developer toward the developer carrier formed by partitioning a developer tank containing a developer carrier that contacts the electrostatic latent image on the latent image carrier with a partition. A supply-side conveyance space for supplying the developer and a collection-side space for collecting the developer from the developer carrier,
It is constituted by a lack part provided in the partition part, and includes a communication part that communicates the spaces,
The communication portion is provided at a position where the developer flows down from the collection side conveyance space toward the supply side conveyance space, and is larger than the total volume of the supply side conveyance space and the collection side conveyance space configured by the partition portion. A developing device characterized in that a part of a developer having a large volume and moving through a communicating portion is retained . The communication portion is provided with a stirring member having a rotating shaft having an axial direction perpendicular to the axis of the conveying screw, and the axial direction of the rotating shaft of the stirring member has an angle with respect to the vertical direction. 6. The developing device according to claim 4, wherein a part of the stirring member is positioned at a position where the developer stays in the direction of gravity due to the inclination of the rotation shaft . The developing device according to claim 7, wherein the agitating member has a rotational direction having a rotational component in a direction in which the developer staying in the gravity direction is lifted .   An image forming apparatus using the developing device according to claim 1.   The image forming apparatus according to claim 9, wherein a developer supply and collection space and a recovery and conveyance space in the developing device are provided in a horizontal direction.   The image forming apparatus according to claim 9, wherein a developer conveyance space and a recovery conveyance space in the developing device are provided in a vertical direction.   The image forming apparatus according to claim 11, wherein the supply conveyance space is positioned on the upper side or the lower side in the vertical direction, and the recovery conveyance space is positioned on the lower side or the upper side in the vertical direction.   The recovery side transport space in the developing device has at least the upstream side of the communication portion where the developer moves from the recovery side transport space toward the supply side transport space in the moving direction of the developer moving toward the inside of the communication portion. The image forming apparatus according to claim 9, further comprising a toner supply unit.

Images