JP3228848B2 - Developer stirring mechanism and developing device incorporating the mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer stirring mechanism disposed in a developer container in a toner container or a developing container, and to a developing device incorporating the stirring mechanism.

[0002]

2. Description of the Related Art A developing device using a two-component developer composed of a carrier formed of magnetic powder such as ferrite and a toner formed of a non-magnetic material such as resin and carbon has been known. Generally, a mixing and stirring mechanism of a developer in a developing device of the type described above includes a screw-type stirring member in which a screw is fixed in a spiral shape around a rotation shaft rotatably mounted in a developing container, or the rotation shaft. A stirrer (simple vibration type stirrer) having a large number of blades connected in parallel to the axial direction, etc., was used for a developing operation in a developing container containing the carrier and the toner. While the toner replenished from the toner container side, which is sequentially replenished in accordance with the amount, is mixed and stirred by the stirring member, the toner and carrier concentration distribution in the container is maintained to be uniform.

In such an apparatus, in order to increase the charging efficiency in recent years, the particle size of the carrier has been reduced, and instead of the carrier formed of magnetic powder such as ferrite on the carrier, the carrier surface has been made more uniform and oxidized in recent years. A so-called resin carrier, in which the surface of a magnetic core material is coated with a resin for prevention, prevention of abrasion of the photoreceptor surface by the carrier, abrasion prevention, and charge control, is often used.

However, when a small-diameter carrier or a resin carrier is used as described above, the difference in specific gravity between the toner and the carrier becomes small, and as a result, the fluidity is greatly reduced. When trying to stir and mix such developer with the screw type or simple vibration type stirring member, the pressing surface of the blade body facing the developer is a surface orthogonal to the rotation direction, so that the rotation of the blade body is Following this, the developer rotates in a ring shape while clinging to the blade body surface, and smooth stirring cannot be performed.

If the blades are made obtuse, the sticking speed will be reduced, but the moving speed of the developer will be slowed down, leading to a delay in the stirring speed. If the pitch at which the blades are arranged is reduced to prevent such a defect, the developer is clogged between adjacent blades. On the other hand, also in the screw blade, the developer interposed between the screw pitches merely rotates in such a manner that the screw cuts inside the accumulation portion of the developer in the form of the meriken powder. Smooth stirring is difficult.

In each of the stirring members, the stirring member is disposed on the rotating shaft in a predetermined direction, so that the developer is conveyed in one direction, and the developer is conveyed to the side wall of the casing at the terminal end in the conveying direction. The developer becomes clogged, the drive torque increases,
The developer leaks from the casing bearing portion, and the inside of the machine is likely to be contaminated.

In order to solve such a drawback, there is a technique in which the inclination direction of the blade body or the helical direction of the screw blade is set to be opposite to the center of the rotation shaft. Are accumulated, the developer on both ends is insufficient, and the toner density in that portion is reduced. For this reason, generally, two stirring shafts whose rotation directions are set in opposite directions are arranged side by side, and a uniform stirring is performed while the developer is moved forward and backward by the respective stirring shafts (Japanese Patent Application Laid-Open No. 62-21679, JP-A-1-123270)
However, such a technique tends to increase the size of the container and the apparatus because two or more stirring members are arranged in parallel.

In order to solve such a drawback, a stirring shaft in which a large number of blades inclined to one side in the axial direction are arranged in the bucket roller for supplying the toner to the developing sleeve side is provided. Among the many blades, a technology in which the blade at the end is inclined in the opposite direction (Japanese Patent Laid-Open No. 62-29167).
9) has been proposed.

[0009]

However, in such a technique, the developer which has been moved forward by the large number of blades has a configuration in which the developer moves back and forth by the oppositely oriented blade body, so that the developer is removed at that portion. The collision not only makes smooth stirring difficult, but also increases the shaft torque.

In view of the drawbacks of the prior art, the present invention provides a developer stirring mechanism and a developing device incorporating the stirring mechanism, which enable smooth and rapid uniform stirring even in the case of a developer containing small particle carriers. To do. Another object of the present invention is to provide a developer stirring mechanism and a developing device incorporating the stirring mechanism, which enable smooth and quick uniform stirring without causing a bias of the developer and an increase in shaft torque. . Furthermore,
An object of the present invention is to provide a developing device that can maintain good stirring performance and charging performance, particularly in a developing device incorporating a magnet assembly.

[0011]

SUMMARY OF THE INVENTION The present invention is intended to achieve the above object effectively by fixing a blade body and a screw blade without rotating the blade body and the screw blade as in the prior art described above. , Its features are basically shown in FIG. FIG. 3 shows a stirring device showing the flow of the developer achieved by the present invention, wherein (A) is a cross section orthogonal to the axial direction,
(B) is a sectional view taken along line BB of (A).

According to the present invention, in a developer stirring mechanism for mixing and stirring a plurality of components of a developer, a partition space forming member (for example, an opening) for moving a developer located outside the partition space to an upper position in the space while taking in the developer located outside the partition space by its rotation. And an opening 1 in which the developer moved to an upper position in the partition space is opened intermittently along the axial direction.
From 5 positions into the partition space forming body (rotary cylinder 11)
To form a partition space while sliding down diagonally in a non-rotating state
A fixed inclined sliding body (for example, the inclined fixed blade 12) discharged outside the body (the rotating cylindrical body 11), and a moving means (for example, a cylindrical body) for moving the developer located outside the partition space in the axial direction with the rotation of the space forming body. 11) Spiral linear projection on outer peripheral surface 13)
Wherein the direction of movement of the developer of the moving means 13 is set to be opposite to the direction of movement of the developer in the axial direction of the inclined slide 12.

In this case, it is preferable to provide a fixed stirring means 19 for stirring the developer moving in the partition space by utilizing the relative rotation between the partition space and the inside of the partition space. Is formed integrally with the inclined slide body,
For example, as shown in FIGS. 6 to 8, when the partition space is formed by the rotating cylinder 11 having the opening 15, one plane is sandwiched by the rotation center of the cylinder 11 in a plane orthogonal to the axis of the cylinder 11. It is formed by arranging the inclined fixed blades 12 on one side and fixed stirring means 19 on the other side. The fixed stirring means 19 is preferably formed of planar fins 19 extending in the axial direction so that the rotary cylinder 11 rotates in the circumferential direction.

Further, it is preferable that the planar fins 19 are arranged at the same pitch interval by being shifted by a half pitch between the arrangement pitches of the inclined fixed blades 12.

The planar fins 19 are fixed to the inclined fixed blades 1.
As shown in FIG. 2, a gap 1 is formed on the outer peripheral side with respect to the inner peripheral surface of the rotary cylinder 11 without being stretched to the inner peripheral surface of the rotary cylinder 11.
It is preferable to form a gap 191 between the planar fins 19 having 90 and the adjacent planar fins 19 in the axial direction.

Returning to the original state, the inclined sliding body 12 has a large number of semicircular fixed blades 12 connected to a fixed shaft 14 penetrating through the inside of the rotary cylinder 11 at a predetermined angle in the axial direction. However, the invention is not limited thereto, and for example, a semicircular screw blade may be cut into a semicircle and fixedly arranged. Further, the partition space forming body 11 is preferably formed by a rotating cylindrical body 11 which covers the outer periphery of the fixed blade 12 and has an opening 15 formed intermittently along the axial direction on the surrounding surface of the fixed blade 12. .

The means for moving the developer to an upper position in the space is provided by disposing the fixed blade 12 on one side in a cross section orthogonal to the axis of the cylindrical body 11 and disposing the fixed blade 12 on the side facing the fixed blade 12. The one-sided space 111 is formed in the body 11, so that the developer can be smoothly raised along the peripheral surface of the cylindrical body 11 by rotating the rotary cylindrical body 11 while using the one-sided space 111.

In this case, in FIG. 8, the planar fins 19 are disposed in the one-side space 111, but the fins 19 are slightly protruded from the fixed shaft 14 and are adjacent to each other even in the axial width. Since only a part of the developer collides with the planar fin 19 due to a large gap between the fins 19, the peripheral surface of the cylindrical body 11 is rotated by the rotation of the rotary cylindrical body 11. The developer can be raised smoothly along the line.

Next, the moving means for moving the developer outside the partition space in the direction opposite to the inclined sliding direction is the cylindrical body 11.
The spiral direction of the spiral linear projection 13 formed on the outer peripheral surface is set to be opposite to the inclination direction of the fixed blade 12 disposed in the cylindrical body 11. In this case, the openings 15 formed on the peripheral surface of the rotary cylinder 11 are preferably formed at appropriate intervals between the pitches of the spiral linear projections 13.

[0020]

According to the present invention, as shown in FIG. 3A, when the cylinder 11 rotates, the developer on the cylinder 11 is rotated together with the cylinder 11 by the spiral linear projections 13 while being rotated. It is conveyed spirally to the right, but falls by gravity from the opening 15 of the cylinder 11. (Arrow A) Further, the developer taken into the one-sided space 111 from the opening 15 by the rotation of the cylindrical body 11 is also conveyed onto the fixed blade 12 while rising along the inner peripheral surface of the cylindrical body 11, 11 and the developer inside and outside are mixed. (Arrow A ')

Thereafter, as shown in FIGS. 3A and 3B,
The developer is obliquely provided along the upper surface of the fixed blade 12 to the cylindrical body 11.
The developer is discharged out of the cylindrical body 11 through the opening of the cylindrical body 11 while sliding down in the direction opposite to the conveying direction of the developer (arrow B), and falls along the gap between the outer edge of the fixed blade 12 and the inner wall of the cylindrical body 11. Due to the difference in speed between the arrow (C) and the drop (arrow B) caused by sliding down of the fixed blade 12, the blade is discharged from the opening 15 to the outside of the cylinder 11 while being stirred more uniformly.

The developer guided to the outer periphery of the cylinder 11 is
In accordance with the rotation, the developer is conveyed rightward in the figure by the spiral linear projection 13 (arrow A). At this time, since there is a speed difference between the cylindrical body 11 and the container casing, the developer frictions with each other. They are charged and uniformly mixed. As a result, the developer is not transported in only one direction,
1, fixed blades 12 or openings 15 inside and outside
Circulates in a closed circuit between the pitches of
The developer is exchanged and mixed inside and outside the cylinder 11 every one rotation, so that the density difference between the inside and outside of the cylinder 11 is eliminated. Further, the conveying speed is faster than that of the simple vibration type, since the basic shape is a spiral screw, so that mixing / stirring can be performed in a short time. Therefore, basically, it is possible to smoothly and promptly perform uniform stirring without causing the bias of the developer and the increase of the shaft torque.

In the present invention, the developer is taken in and out of the rotary cylindrical body 11 (partition space forming body) through the fixed blades 12 functioning as fixed inclined sliding bodies, thereby discharging the small particle carrier. Even in the case of a developer containing, smooth and quick uniform stirring is enabled. Further, since the fixed blade 12 is fixed and merely slides down in the axial direction, there is no danger of the developer containing the small particle carrier being stuck to the fixed blade 12.

In the case of circulating in the closed circuit between the pitches of the fixed blades 12 or the openings 15 as in the present invention, when the end of the cylinder 11 is provided in the middle of the closed circuit, there is a deviation in that portion. Occurs. In addition, since it is difficult for the opening 15 to pump the entire amount of the spiral linear projections 13 on the outer periphery of the cylindrical body 11, the remaining developer is sequentially guided to the axial end side of the cylindrical body 11, and the deviation is also shifted. Occurs.

Therefore, as shown in FIG. 2, according to the present invention, the developer is caused to flow back toward the center toward the center of the partition space forming means 11 located at the most downstream side in the developer moving direction. The above problem is dealt with by arranging the return means 16 for returning to the inside. In this case, the return means 1
6 is a second linear projection 13 formed in a direction intersecting an extension of the spiral linear projection 13;
It is formed by a combination of openings formed on the peripheral surface of the cylindrical body 11 located inside the inside.

According to this invention, as shown in FIG. 3B, the developer conveyed to the end of the cylindrical body 11 simply moves backward in the direction opposite to the conveying direction as in the prior art. Without returning the developer in the direction intersecting with the transport direction without moving backward in the opposite direction, the returned developer is
It is introduced into the cylindrical body 11 through the opening 15, and slides again toward the center side by the fixed blade 12 in the cylindrical body 11. As a result, in any case, a circulation circuit is formed at the end side of the cylindrical body 11. Will be.

The drop (arrow C) along the gap between the outer edge of the fixed blade 12 and the inner wall of the cylindrical body 11 shown in FIG.
As shown in FIG. 8, it is preferable to provide a fixed stirring means (plane fins 19) so as to further increase the speed difference from the drop (arrow B) caused by sliding down with the slide 2.

When the developer which has been slid down by the fixed blades 12 moves along the inner peripheral surface of the rotary cylinder 11 again, a part of the fixed stirring means 19 is partially connected to the stirring means 19. Mixing with the developer which collides with the developer and falls down and slides down due to the inclined slide body, the preferred stirring is performed, and the other developer not caught by the stirring means 19 is the inner periphery of the rotary cylinder 11. It moves upward along the surface or is discharged out of the cylindrical body 11 through the opening 15. Accordingly, in the configuration in which the fixed stirring means 19 is provided, mixing with a difference in speed can be performed without providing the spiral linear projection 13 on the outer peripheral surface of the cylindrical body 11.

In the case of the invention shown in FIG. 8, when the partition space is formed by the rotating cylinder 11 having the opening 15, the fixed stirring means 19 is used to rotate the rotating cylinder 11 in the circumferential direction. , Planar fins 19 extending in the axial direction
The developer that rotates in the circumferential direction by forming the fins 1
It collides with 9 and is effectively dropped downward, which is preferable.

In this case, the planar fin 19 is not particularly limited as long as it has a predetermined surface width on the side facing the rotating direction of the developer, in addition to the plate-like fin, and is formed in a triangular or rectangular block shape. You may. Further, in a plane orthogonal to the axis of the cylindrical body, the inclined fixed blade 12 is disposed on one side and the fixed stirring means 19 on the other side with the rotational center of the cylindrical body interposed therebetween. It is preferable that the sliding and agitation are repeated as necessary by disposing at the same pitch while being shifted by a half pitch between the disposing pitches.

Further, the planar fins 19 are fixed to the inclined fixed blades 1.
By forming a gap on the outer peripheral side with respect to the inner peripheral surface of the rotating cylinder 11 without extending the inner peripheral surface of the rotating cylinder 11 just to the limit as in 2, the finely stirred fine toner can be centrifuged. Due to the action of the force, the rotary cylinder 11 moves upward along the inner peripheral surface, and the solid toner, which has not been sufficiently stirred and is partially solidified, may collide with the planar fin 19 located at the center side. As a result, the stirring effect is further enhanced.

A sixth aspect of the present invention is an invention in which the stirring mechanism is suitably incorporated in a developing device in which a roll-shaped magnet assembly is disposed in the developing container 1, wherein the rotary cylinder 11 is aligned with the axis of the assembly. The stationary blades 12 are disposed substantially parallel to each other, and the fixed blades 12 are disposed closer to the anti-assembly side in a cross section orthogonal to the axis of the rotary cylinder 11, and the fixed blades 12 face each other in the cylinder 11 facing the fixed blades 12. It is characterized in that the side is a one-sided space 111 area. According to the present invention, the magnetic spikes are formed by the roll-shaped magnet assembly, and the magnetic spikes directly enter the openings 15, so that the developer can be efficiently taken in.

[0033]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; However, unless otherwise specified, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention, but are merely illustrative examples. Not just. FIG.
1 shows an internal configuration of the developing device according to the embodiment of the present invention, and a mechanical configuration thereof will be briefly described. 1 is a developing container in which a carrier and a toner are stored at a predetermined concentration ratio, and rotates in a direction D shown by an arrow. A developing sleeve 4 containing a mag roll (magnet assembly) 4a is rotatably supported in the direction of the arrow S on the opening 15 side facing the photoreceptor drum 3, and the axial line of the adult is located on the back side of the developing container 1. The cylindrical stirring member 10 is disposed in parallel with the above.

The toner container 2 is detachably mounted on the wall surface of the developing container 1 on the opposite side of the developing sleeve 4 facing the stirring member 10 through the slit opening 2a.
A sponge-covered toner replenishing roller 5 is rotatably mounted on the slit opening 2a, and is connected to the replenishing roller 5 based on a T / C detection signal from a toner density detection sensor 6 provided at the bottom of the developing container 1. By controlling the rotation of a DC motor (not shown), the toner supply amount can be adjusted arbitrarily. Reference numeral 7 denotes a doctor blade for regulating the layer thickness of the developer magnetically held on the developing sleeve.

As shown in FIGS. 2 and 3, the agitating member 10, which is a main part of the present invention, rotates upward from the lower side on the side facing the developing sleeve 4, while rotating downward from the upper side on the toner container 2 side. As described above, the hollow cylindrical body 11 rotating clockwise, the fixed shaft 14 penetrated along the center line in the hollow cylindrical body 11, and the fixed shaft 14 inclined at a predetermined angle along the axial direction. It comprises a number of fixed blades 12 connected in series and a spiral linear projection 13 formed along the outer peripheral surface of the cylindrical body 11.

As shown in FIG. 2A, both ends of the rotary cylinder 11 are sealed, and a rotary shaft 11a is provided on one side of the sealed end surface.
And a spiral linear projection 13 having a predetermined pitch is formed on the rotating outer peripheral surface. In addition, the rotating cylinder 1
1 is formed to have a diameter such that a part of the developer 8 is exposed from the collecting surface of the developer 8 in the container.
Is preferably set in a range from the center of the fixed shaft to the upper end of the fixed blade 12.

The linear projection 13 is formed between the linear projection 13 and the bottom of the container 1.
In a state in which the developer is not in contact with the surface of the sensor 6, the projection has a height such that the developer can be transported.
Determined in relation to 5 areas. The openings 15 are formed at an appropriate pitch between the pitches of the spiral linear projections 13, and the opening 15 is formed at a 180 ° symmetrical position of the cylindrical body 11 with the narrow strip rib 11 extending in the axial direction and the linear projection 13. Are formed in a substantially parallelogram shape in an airspace sandwiched between the two.

The openings 15 do not necessarily have the openings 15 between the pitches of all the linear projections 13. For example, when the number of the openings 15 increases, the amount of the developer to be drawn into the cylinder increases, but the adjacent openings 15 do not. Since the water is immediately discharged, the conveyance distance is reduced, and as a result, the water may be discharged while the fixed blade 12 slides down, which will be described later, and the stirring efficiency is reduced. On the other hand, when the number of the openings 15 is reduced, the amount of the developer to be drawn into the cylinder is reduced. However, the fixed blade 12 is located between the projection pitches (closed portions) where the openings 15 are not formed.
Is repeated, so that the stirring efficiency is improved.

Therefore, the closed portion and the opening 15 are arbitrarily set in relation to the pumping amount and the stirring efficiency. In this embodiment, the closed portion is formed so that the back side of the front and back double-sided openings 15 perpendicular to the axis becomes the closed portion. The opening 15 is shifted every other pitch in the axial direction, and the opening 15 is formed at every other pitch on both ends in the axial direction. In other words, it is preferable that the opening 15 is increased at both ends of the rotary cylinder 11 and the opening is decreased at the center.

The end of the spiral linear projection 13 in the forward direction due to the rotation of the cylindrical body 11, in other words, the linear projection 13
Rotating body 11 located at the most downstream side in the developer transport direction due to
Of the spiral linear projection 13 on the end side of the shaft is stopped at an intermediate position, and a second linear projection 14 that is set in a direction opposite to the linear projection 13 is formed on the peripheral surface of the shaft end located at an extension of the spiral linear projection 13. An opening 15 is provided on the peripheral surface of the cylindrical body 11 between the second linear projection 14 and the first linear projection 13, and the second linear projection 13 causes the backflow toward the center. Developer 11
It is configured to be returned inside. At this time, by providing the rib-like protrusions 131 communicating between the adjacent linear protrusions 13 at predetermined intervals in the axial direction, the conveying force is further increased.

On the other hand, as shown in FIG. 2 (B), the fixed blade 12 disposed in the rotary cylinder 11 is formed by dividing a semi-ellipse divided into two in the major axis direction into an air space on the side opposite to the sleeve 4 in the cylinder 11. And is fixed to the fixed shaft 14 at a predetermined pitch at a predetermined angle. At this time, the fixed blade 12 is in the state shown in FIG.
The elliptical shape is set so as to be a true semicircle in the projection in the axial section direction as shown in FIG. The fixed shaft 14 having the fixed blades 12 connected thereto protrudes from the end surface of the cylinder 11 opposite to the rotation shaft of the cylinder 11 and is fixed to the wall surface of the developing container 1.

As a result, the relationship between the cylindrical body 11 and the fixed blades 12 is as shown in FIG. That is, FIG.
As shown in (A), the semicircular space inside the cylindrical body 11 on the side of the developing sleeve 4 is an air space space where the fixed blade 12 does not exist.
On the other hand, the peripheral surface of the cylindrical body 11 has openings 1 intermittently at appropriate intervals in the axial direction.
5 is formed, and since the side of the opening 15 is cut obliquely in a direction intersecting the inclination direction of the fixed blade 12, the rotation of the cylindrical body 11 in the clockwise direction The developer taken into the cylinder 11 is conveyed upward while moving to the closed portion 113 on the inner peripheral surface side of the cylinder 11 according to the rotation of the cylinder 11.

On the other hand, rotation of the cylinder 11 causes the cylinder 11
The developer on the peripheral surface is formed into a cylindrical body 1 by a spiral linear projection 13.
While being rotated together with 1, it is conveyed rightward in the figure, drops from the cylindrical opening 13 by gravity, and the developer inside and outside the cylindrical body 11 is mixed as described in the section of the operation. At this time, FIG.
As shown in FIG.
The magnetic chain formed above is easily transported upward while cutting the magnetic chain directly at the opening 15 in order to easily enter the opening 15 of the cylindrical body 11, and deteriorated from the developing sleeve 4 side. The developer can be easily replaced.

On the other hand, a semi-elliptical fixed blade 1 inclined at a predetermined angle is provided in a semi-circular space inside the cylindrical body 11 on the side opposite to the developing sleeve 4.
2 is stored, and as a result, the developer conveyed above the cylindrical body 11 slides down the upper surface of the fixed blade 12 and is discharged to the outside of the cylindrical body 11, and is discharged into the gap between the cylindrical body 11 and the blade body 12. Due to the speed difference due to the falling along and the sliding of the fixed blade 12, the liquid is discharged from the opening 15 to the outside of the cylindrical body 11 while being stirred more uniformly. At this time, when the fixed blade 12 is located in the closed portion, the inside of the cylindrical body 11 is raised again, and is discharged from the next cylindrical body 11 opening 15 while sliding down the upper surface of the next fixed blade 12. And further stirring becomes possible.

The developer discharged from the opening 15 to the outer periphery of the cylinder 11 is conveyed in the direction of the origin by the spiral linear projection 13 according to its rotation, and there is a speed difference between the cylinder 11 and the container casing. As a result, the developers are rubbed against each other, charged and uniformly mixed. As a result, the developer is not conveyed only in one direction, but circulates in a closed circuit between the pitches of the respective fixed blades 12 or the openings 15.

On the forward end side of the spiral linear projection 13, a second linear projection 13 formed in a direction intersecting with an extension of the spiral linear projection 13 causes the spiral linear projection 13 to form a cylindrical body. The developer conveyed to the 11 end side is introduced into the cylindrical body 11 through the opening 15 while returning in the direction intersecting with the conveying direction instead of simply returning in the opposite direction to the conveying direction. Fixed blade 12 again in body 11
As a result, a sliding circuit is formed on the end side of the cylindrical body 11 in any case as a result.

Therefore, in the present embodiment, a triangular circulation path in the antigravity direction / gravity + axial direction / axial direction is formed between the adjacent openings 15, and as a result, the bias of the developer and the increase of the axial torque are reduced. The uniform stirring can be performed smoothly and promptly without generating. In this embodiment, since the fixed blade 12 is fixed without rotating and functions as an inclined sliding body, even when a small particle size or a resin carrier is used, the fixed blade 12 does not stick to the fixed blade 12. . In addition, by taking in and discharging the developer from the opening 15 provided in the rotary cylinder 11 together with the sliding operation of the fixed fixed blade 12, smooth and prompt uniform stirring can be performed even in the case of the developer containing the small particle carrier. To Further, in the present embodiment, since the second linear projection 13 and the opening 15 are provided at the end side of the rotary cylindrical body 11 located at the most downstream side of the spiral linear projection 13 in the developer conveying direction, the developer is always provided. Can be returned into the rotary cylinder 11 while flowing backward toward the center side, so that an increase in axial torque and a deviation do not occur.

In this apparatus, in order to confirm the effects of the present invention, a 30 mm photosensitive drum and a 16 mm mag roll were used, the inside / outside diameter of the cylinder 11 was 16/18 mm, and the height of the linear projection 13 was 1 mm. The angle of the linear projection 13 is 45 °, and the shape of the opening 15 is set as shown in FIG. On the other hand, fixed blade 1
2 is a fixed blade diameter of 14φ, a fixed blade inclination angle of 30φ,
The blade pitch is set to 8 mm, and the number of rotations is set to 62 rpm. The device is used in such a manner that the developer is configured such that conductive fine particles are fixed on the surface of carrier base particles in which a magnetic substance is uniformly dispersed in a binder resin, and has an average particle size of about 35 μm and 3.0. A magnetic substance is added to a carrier having a true density of about 4.5 g / cm ³ , a binder resin, a colorant, a charge control agent, an anti-offset agent, and the like, so that the average particle size is 7 μm.
m and a true density of 2.0 to 2.5 g / cm ³ , for example, in a developing container 1 having an axial length of 230 mm, a blade diameter of 18 mm,
A simple vibration type stirring member 10 'having a blade inclination angle of 30 ° and a rotation speed of 62 rpm is incorporated. The gap between each of the stirring members 10 and 10 'and the wall of the developing container 1 is set to 1.5 mm.

Next, a developer having a T / C of 12% and a developer having a T / C of 8% are distributed from the upper portion of the developing container 1 to the left and right from the axial center position of the stirring member. After the rotation shafts 10 and 10 'are thrown in such a degree that the rotation shafts 31 and 10' are hidden, the stirring members 10 and 10 'of the comparative example and the embodiment are rotated, and the rotation is performed in the developing container 1 shown in FIGS. 4 (B) and 5 (B). 4 (A) and 5 (A) show the results of chronologically examining the mixing state of the developer at each measurement point. As is clear from this figure, the stirrer according to the present embodiment converged in only about 3 minutes, whereas the comparative example took 20 to 25 minutes to converge,
It was confirmed that the stirring effect of this example was significantly improved by several steps as compared with the comparative example.

FIGS. 6 to 8 show the fixed shaft 14 of the above embodiment.
6 and 7 in another embodiment in which a planar fin 19 for stirring the developer moving in the rotary cylinder 11 by using relative rotation between the rotary cylinder 11 is provided. As shown in the figure, a large number of fixed blades 12 connected to the fixed shaft 14 by being inclined at a predetermined angle in the axial direction on one side of a fixed shaft 14 penetrating on the center axis of the rotary cylinder 11 having the opening 15
In a plane orthogonal to the axis of the cylinder 11
The one-sided space is arranged with one rotation center interposed therebetween, and the planar fins 19 are arranged at predetermined pitch intervals in the axial direction in the one-sided space 111 on the other side.

That is, the planar fin 19 has a rectangular plate shape, and is fixed on the fixed shaft 14 along the axial direction along the inclined fixed blade 12.
Are arranged at the same pitch in the axial direction while being shifted by half a pitch between the arrangement pitches. The planar fin 19 is erected from the fixed shaft 14 at a height of about の of the radius of the rotary cylinder 11, and a gap 19 with the inner peripheral surface of the rotary cylinder 11.
0 is set to a value sufficiently larger than the gap between the inclined fixed blade 12 and the inner peripheral surface of the rotary cylinder. Also, in the axial width of the planar fin 19, the space 191 is formed such that the interval between adjacent fins is larger.

According to this embodiment, as shown in FIG. 8, the developer on the outer periphery of the cylindrical body 11 is rotated by the spiral linear projection 13 together with the cylindrical body 11 by the rotation of the cylindrical body 11 as shown by an arrow A in FIG. As shown, it falls from the upper part of the opening 15 of the cylindrical body 11 to the upper surface side of the fixed blade 12. Further, the developer taken into the one-sided space 111 from the opening 15 by the rotation of the cylindrical body 11 is also conveyed onto the fixed blades 12 while rising along the inner peripheral surface of the cylindrical body 11, and developing inside and outside the cylindrical body 11 is performed. The agents are mixed. (Arrow A ′) At this time, since the planar fin 19 protrudes from the fixed shaft 14 with a sufficient gap 190 between itself and the inner peripheral surface of the cylindrical body 11, the developer flows along the inner peripheral surface of the cylindrical body 11. There is nothing wrong with moving up.

Thereafter, the developer is discharged out of the cylindrical body 11 through the opening of the cylindrical body 11 while sliding down the diagonally along the upper surface of the fixed blade 12 in the direction opposite to the direction of transport of the developer on the cylindrical body 11. (Arrow B), the outer edge of the fixed blade 12 and the cylindrical body 1
Due to the speed difference between the falling along the gap between the inner walls (arrow C) and the falling due to the sliding of the fixed blade 12 (arrow B), a part of the cylindrical body 11 is more uniformly stirred through the opening 15.
If the lower end of the fixed blade does not face the opening outside, it moves upward again along the inner peripheral surface of the cylindrical body 11.

[0054] The time slipped down a portion of the fixed blade 12 as indicated by arrow E ₂ falls downward by colliding with the planar fins 19 as indicated by arrow E ₁ in FIG. 8 during this movement Mixing with the delayed developer causes favorable agitation, and is discharged to the outside through the opening 15, while the other developer that has not collided with the planar fin 19 as shown by the arrow D is again on the other adjacent side. The drops fall on the upper surface of the fixed blade 12, and the above operation is repeated. As a result, the developer collides with a speed difference over the inner and outer peripheries of the cylindrical body, and charging and stirring can be performed more efficiently than in the above-described embodiment.

In order to confirm the difference between the present embodiment and the embodiment shown in FIG. 3, as shown in FIG. After the developer of 12% and the developer of 8% are distributed to the left and right from the axial center position of the rotary cylinder 11 and charged so that the rotary shaft 31 of the cylindrical stirring member 10 is hidden, the developing container 1 FIG. 9 shows the result of chronologically examining the mixing state of the developer at each measurement point in the inside.

As is clear from the drawing, the agitation member of this embodiment converged in only about 2.5 minutes. However, in the above-described embodiment, the time until the converging was 3 minutes. It was confirmed that the stirring effect of the example was significantly improved by several steps. FIG. 1 shows the planar fins 19 by imaginary lines.

[0057]

As described above, according to the present invention, stirring and mixing can be carried out smoothly and in a short time even with a developer having low fluidity or small particles, and simplification and weight reduction can be achieved during the constitution. You. Further, according to the present invention, it is possible to smoothly and quickly perform uniform agitation without causing a bias of the developer and an increase in shaft torque. Further, according to the present invention, it is possible to provide a developing device which can maintain good stirring performance and charging performance, particularly in a developing device incorporating a magnet assembly. And so on.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an internal configuration of a developing device according to an embodiment of the present invention.

FIG. 2 shows the shape of a stirring member according to the present invention. FIG. 2 (A) is a front view of a main part (fixed blades and the like are actually removed from an opening, but in order to make the external shape of a rotary cylinder easy to understand, the display is shown. (B) shows a cutaway front view on the end side after rotating by 90 °, in which the fixed blade portion is clearly shown. .

3A and 3B are explanatory views showing a cross-sectional shape of a stirring member and a flow of a developer according to the present invention, wherein FIG. 3A shows an axial cross-sectional shape, and FIG.

FIG. 4A is a graph showing a time-series distribution of the mixing ratio of the toner and the carrier in the stirring member of the present invention;
(B) is a schematic diagram showing measurement points on the graph.

FIG. 5A is a graph showing a time-series distribution of a mixing ratio of toner and carrier in a stirring member of a comparative example (prior art), and FIG. 5B is a schematic diagram showing measurement points in the graph.

FIG. 6 is an overall front view of a main part with a rotary cylinder removed, showing a positional relationship between fixed blades and planar fins according to another embodiment of the present invention.

FIG. 7 is a side view of a main portion of a notch on an end side after rotating FIG. 6 by 90 °.

FIG. 8 is an explanatory view showing a cross-sectional shape of a stirring member and a flow of a developer according to another embodiment of the present invention, showing a front cross-sectional shape.

FIG. 9 is a graph showing a time-series distribution of the mixing ratio of the toner and the carrier in another embodiment of the present invention shown in FIGS. 6 and 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Developing container 4a Roll-shaped magnet assembly 11 Rotating cylinder 12 Fixed blade 13 Spiral linear protrusion 16 Second linear protrusion 15 Opening 19 Planar fin 190 Void

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-97166 (JP, A) JP-A-4-174471 (JP, A) JP-A-61-197026 (JP, A) JP-A 57-97 141665 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 15/08

Claims (12)

(57) [Claims] 1. A developer stirring mechanism that mixes and stirs a plurality of components of a developer, wherein a partition space forming body that moves the developer located outside the partition space to an upper position in the space by taking in the developer by rotation of the developer stirring mechanism. Forming a partition space from the opening position where the developer moved to the upper position in the space is opened intermittently along the axial direction
Take it into your body and slide it down
A fixed inclined slide body to be discharged out of the partition space forming body, and a moving means for moving the developer located outside the partition space in the axial direction by rotation of the space forming body, the developer moving direction of the moving means, A developer stirring mechanism characterized in that the direction of movement of the developer in the axial direction of the inclined slide body is set in the opposite direction. 2. A return means for returning the developer back to the center while returning the developer back into the partition space at an end of the partition space forming member located at the most downstream side in the developer movement direction. The described developer stirring mechanism 3. A developer stirring mechanism that mixes and stirs a plurality of components of a developer.
A rotating cylinder having openings formed intermittently along the axial direction on the surrounding surface of the envelope, wherein the fixed blades are arranged on one side in a cross section orthogonal to the axis of the rotating cylinder. A developer agitating mechanism, wherein a one-sided space is formed in the cylinder facing the fixed blade. 4. A spiral linear projection is formed on an outer peripheral surface of the cylindrical body, and a spiral direction of the linear projection is set to a direction opposite to a downward inclined direction of a fixed blade disposed in the cylindrical body. 3. A developer stirring mechanism according to item 3. 5. The return means has a second linear projection formed in a direction intersecting an extension of the spiral linear projection, and an opening on a cylindrical peripheral surface located inside the linear projection. 3. The developer stirring mechanism according to claim 2, wherein the developer stirring mechanism is a combination of openings. 6. A developing device in which a developer stirring mechanism is disposed in a developing container containing a plurality of components of developer and opposed to a roll-shaped magnet assembly, wherein the developer agitating mechanism is substantially parallel to an axis of the assembly. A rotating cylinder that is disposed and moves the developer located on the side facing the assembly upward by the rotation thereof to a position above the cylinder, and the developer that is disposed on the anti-assembly side in the cylinder and drops on the upper surface thereof. Aperture position opened intermittently along the axial direction
Taken into the rotating body from the stand, and slipped diagonally in a non-rotating state
And a moving means for moving the developer in the axial direction according to its rotation on the outer peripheral surface of the cylindrical body, wherein the moving direction of the developer of the moving means is a slanted sliding body. Developing device having a developer stirring mechanism in which the direction of movement of the developer in the axial direction is set in the opposite direction. 7. The rotating cylinder has a space area on the side facing the assembly and a fixed blade housing area on the opposite side of the assembly, and the moving means is a spiral linear projection formed on the outer periphery of the cylinder. > The opening formed on the peripheral surface of the cylindrical body is
7. The developing device according to claim 6, wherein the developing device is appropriately formed between the pitches of the spiral linear projections. 8. A developer stirring mechanism that mixes and stirs a plurality of components of a developer, wherein a partition space forming body that moves the developer located outside the partition space to an upper position in the space by taking in the developer by rotating the developer stirring mechanism. The developer moved to an upper position in the space is skewed obliquely along the axial direction and is discharged to the outside of the cylinder while being skewed. The relative rotation between the inclined space and the inside of the partition space is used to move in the partition space. And a fixed stirring means for stirring the developing agent. 9. When the fixed stirring means is formed integrally with the inclined slide body, or when the partition space is formed by a rotating cylinder having an opening, in a plane orthogonal to the axis of the cylinder, 9. An inclined fixed blade is provided on one side of the center of rotation of the cylindrical body and fixed stirring means is provided on the other side.
The described developer stirring mechanism 10. A moving means for moving the developer located outside the partition space in the axial direction to rotate the space forming member, wherein the moving direction of the developer is changed in the axial direction of the inclined sliding body. 9. The developer stirring mechanism according to claim 8, wherein the developer moving direction is set in the opposite direction. 11. The fixed stirrer according to claim 9, wherein said fixed stirring means is formed of planar fins, and said planar fins are arranged at the same pitch by being shifted by a half pitch between arrangement pitches of the inclined fixed blades. Developer stirring mechanism 12. The rotating cylindrical body according to claim 9, wherein the planar fin has a gap on the outer peripheral side with respect to the inner circumferential surface of the rotating cylinder so as to be larger than the gap between the inclined fixed blade and the inner circumferential surface of the rotating cylinder. Developer stirring mechanism