JPH08278698A - Developing device of one component system - Google Patents

Abstract

PURPOSE: To provide a developing device of one component system capable of preventing toner from becoming a lumpy state. CONSTITUTION: The developing device of the one component system is composed in a type provided with a first transporting chamber 5a and a second transporting chamber 5b, and the toner is circulated between them. Moreover, the developing device of the one component system is composed that projections 4a and 4d in a specified shape, or the third transporting means is respectively disposed in-between the first transporting chamber 5a and the second transporting chamber 5b, corner parts 4a and 4b of the second transporting chamber is indivitually formed as a curved surface, or a vibration member is disposed on the corner parts 4a and 4b in the second transporting chamber. As for the developing device of one component system, since regions for the toner liable to stay is indivitually eliminated in the developing device and flow of the toner in the developing device is made smooth at the same time, the toner is prevented from being gathered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a one-component developing device which uses toner, that is, one-component developer, for use in an image forming apparatus such as a copying machine and a printer. The present invention relates to improvement of a one-component developing device of a type in which toner is circulated.

[0002]

2. Description of the Related Art Conventionally, this type of one-component developing device is
As shown in FIG. 16, a developing roll 21 arranged to face the latent image carrier and a developing roll 21 arranged in parallel to the developing roll 21.
A first conveying unit 22 that rotates to convey toner in one direction
And a second conveying unit 23 which is arranged in parallel with the developing roller 21 with the first conveying unit 22 interposed therebetween and which rotates to convey toner in a direction opposite to that of the first conveying unit 22, and a developing unit. A housing 24 for holding the roll 21, the first conveying means 22 and the second conveying means 23 is provided, and the housing 24 has the first conveying means 22 and the second conveying means 23.
And a toner circulating portion 24a having an opening formed on one side surface to expose the developing roll 21 (Japanese Patent Application Laid-Open Nos. 1-195473 and 4-2180).
78, JP-A-6-35317).

The toner in the toner circulating portion 24a is conveyed in one direction by the first conveying means 22, and the second conveying means 2 is arranged at the downstream end in that direction.
3 is carried in the direction of 3 and is carried by the second carrying means 23 in the direction opposite to that of the first carrying means 22, and at the downstream end in that direction, in the direction of the first carrying means 22. By being conveyed, it circulates in the toner circulation unit 24a.

[0004]

However, since the toner has a small particle size, the toner circulating portion 24a between the first transporting means 22 and the second transporting means 23 is located on the side surface side or the second side. It is difficult for the toner carrying force of the first carrying means 22 or the second carrying means 23 to act on the corners of the carrying means 23 in the carrying direction (hereinafter collectively referred to as dead spaces), and toner is likely to accumulate. .

The toner accumulated in the dead space is circulated in the toner circulating portion 24a facing the dead space.
Adhere to the side surfaces of the toner particles, and their surfaces are adhered to each other due to a change in temperature or humidity to agglomerate (hereinafter, the toner in this state is referred to as agglomerated toner). Further, when vibration or shock is applied to the developing device, for example, when the developing device is used in a copying machine, vibration or shock is applied to the developing device due to opening / closing of the platen or opening / closing operation of the storage tray. However, in such a case, the agglomerated toner may peel off. Further, when the toner clumped and peeled off from the side surface circulates in the toner circulation portion and is adsorbed to the developing roll, the specific charge amount is reduced and the toner image does not fly to the latent image carrier and white spots appear on the toner image. May occur, or the toner may adhere to the latent image carrier due to its large diameter to form black spots on the toner image, or the toner may adhere to the developing roll due to being sandwiched between the layer thickness regulation plate and the developing roll due to its large diameter. An undeveloped portion is formed to cause white streaks in the toner image, resulting in an image quality defect in the toner image. Further, when the agglomerated toner sandwiched between the layer thickness regulating plate and the developing roll is decomposed, a toner layer having a low charge amount is continuously formed on the developing roll and the toner adheres to the latent image carrier. If black streaks are formed on the developing roll or if decomposition occurs over a wide area, a toner layer with a low charge amount is formed over a wide area on the developing roll to form a normal toner layer. The density unevenness occurs between the toner image and the toner image, resulting in an image quality defect in the toner image.

Further, in the above-described one-component developing device, the toner is circulated by the two conveying means 22 and 23 which are arranged in parallel and convey the toner in the opposite directions.
The flow of toner is apt to be stalled at the downstream side of the first conveying means 22 and the second conveying means 23 in the conveying direction. In particular, when a large number of small-sized originals are copied, the toner consumption is small and the conveying direction is small. Since the amount of toner conveyed to the downstream portion is large, the first conveying unit 22 and the second conveying unit 23
The toner accumulates at a site on the downstream side in the conveyance direction of.

Immediately after that, when a large-sized original is copied, the toner accumulated on the downstream side of the first conveying means 22 in the conveying direction causes uneven charging, and a toner image developed with the toner is generated. Will result in poor image quality.

Therefore, it is an object of the present invention to provide a one-component developing device in which toner does not accumulate in the toner circulating portion.

[0009]

SUMMARY OF THE INVENTION The present invention is directed to a developing roll arranged to face a latent image carrier and a first developing roll arranged in parallel with the developing roll and rotating to convey toner in one direction. Developing means and a second conveying means which is arranged in parallel with the developing roll with the first conveying means interposed therebetween and which rotates and conveys toner in a direction opposite to the first conveying means. ,
A housing for holding the first carrying means and the second carrying means, wherein the housing is formed around the first carrying means and the second carrying means, and the developing roll is exposed on one side surface. We propose four inventions on the premise of a one-component developing device in which a toner circulation portion having an opening is formed.

That is, according to the first aspect of the invention, the protrusion is formed on the side surface of the toner circulating portion between the first conveying means and the second conveying means, and the protrusion is projected toward the inside of the toner circulating portion. A one-component developing device having a central portion and an inclined surface portion inclined from the central portion toward the side surfaces of the toner circulating portion on the first conveying means side and the second conveying means side.

According to a second aspect of the present invention, the corner portion in the carrying direction of the second carrying means is formed into a curved surface, and the curved surface is shaped so as to generate a carrying force in a direction orthogonal to the toner carrying direction. Is a one-component developing device.

A third aspect of the invention is a one-component developing device in which the third conveying means is arranged in the toner circulating portion between the first conveying means and the second conveying means.

A fourth invention is a one-component developing device in which a vibrating member is arranged at a corner portion of the second carrying means in the carrying direction.

In the first aspect of the present invention, the protrusion is provided on a central portion protruding toward the inside of the toner circulating portion, and on side surfaces of the toner circulating portion on the first conveying means side and the second conveying means side from the central portion. It may have any inclined surface portion that is inclined toward the side, and may be, for example, a trapezoidal shape, a wedge shape, or a tapered shape. The projection is set in relation to the toner carrying force of the first carrying means or the second carrying means. For example, the projection is provided in the vicinity of the area in the toner circulating unit where the toner carrying force acts. It may be formed so that the vertices of are located.

In the second aspect of the invention, as means for forming the corner portion on the curved surface, the corner of the toner circulating portion itself may be formed on the curved surface, or a curved plate is formed inside the corner of the toner circulating portion. May be provided. In addition, the curved surface having a shape that generates a conveying force in a direction orthogonal to the toner conveying direction means a shape in which a tangent plane at least at an arbitrary portion of the curved surface is not orthogonal to the toner conveying direction.

In the third aspect of the present invention, the third conveying means may be any means as long as it can convey toner between at least the first conveying means and the second conveying means. A plurality of third transport members, for example, a paddle provided with a third transport member formed in a U shape around the rotary shaft, or a plurality of the third transport members around the endless belt. There is a conveyor belt provided.

As a method of rotating the third conveying means, the third conveying means may be rotated from the outside of the developing device, but the rotation of the first conveying means and / or the second conveying means is used. If so, it can be easily rotated without adding a new driving member. For example, when using a conveyor belt as the third conveyor means, the first conveyor means and the second conveyor means are designed to rotate in the same direction, and the first conveyor means and the second conveyor means are rotated. A conveyor belt may be stretched between the conveyor and the conveyor. Even when the first transporting means and the second transporting means are rotated in the same direction, for example, if the winding directions of the agitator are reversed,
The toner carrying direction by the first carrying means and the toner carrying direction by the second carrying means can be reversed. Further, when the transport belt is stretched between the portion on the downstream side of the first transport means and the portion on the upstream side of the second transport means, the toner under the transport belt is So that it is conveyed from the conveying means in the direction of the second conveying means,
It is necessary to set the rotation directions of the first transport means and the second transport means.

In the fourth aspect of the present invention, the vibrating member may include a vibrating plate arranged at least at the corners, and the vibrating plate may be vibrated. The second conveying means may be constituted by a leaf spring member arranged so as to come into contact with and flex at each rotation, and the spring wire provided in the second conveying means and the spring wire are It may be configured by a plate member arranged so as to bend by abutting each second rotation of the second conveying means. Further, the plate member arranged at the corner and the plate member and the housing It may be configured with a compression spring which is disposed between the two and is bent by the toner carrying force of the first carrying means and pushes the plate member until it comes into contact with the second carrying means when the toner carrying force is not present.

As a material which can be used as the plate member, there is a film made of PET (polyethylene terephthalate).

The surface of the protrusion in the first invention, the surface of the third conveying means in the second invention, the surface of the curved surface formed in the corner in the third invention, or the vibration of the fourth invention. The surface of the member may be subjected to a surface treatment (coating, taping, etc.) with a material having the same polarity as the toner due to the charging train, such as Teflon, which makes it difficult for the toner to adhere to the surface of the member or the like. The toner flow is smooth.

[0021]

In the first aspect of the invention, the protrusion is formed on the side surface of the toner circulating portion between the first conveying means and the second conveying means, and the protrusion is formed between the first conveying means and the second conveying means. Since the portion where the toner carrying force by the first carrying means or the second carrying means is hard to act is eliminated, there is also no place where the toner is accumulated. Further, the protrusion is formed of a central portion protruding toward the inside of the toner circulating portion and an inclined surface portion inclined from the central portion toward the side surfaces of the toner circulating portion on the first conveying means side and the second conveying means side. Therefore, the toner smoothly flows near the surface of the protrusion.

According to the second aspect of the invention, the corner portion in the carrying direction of the second carrying means is formed into a curved surface, and the curved surface is shaped so as to generate a carrying force in a direction orthogonal to the toner carrying direction. Since it is formed in the above, there is no place where the toner is accumulated at the above corners. Further, the curved surface is formed in a shape that causes a conveying force in a direction orthogonal to the toner conveying direction, and the toner conveying force by the first conveying means or the second conveying means acts on the curved surface, Since the conveying force is made to act along the curved surface,
The toner flows smoothly near the curved surface.

In the third invention, the third conveying means is arranged in the toner circulating portion between the first conveying means and the second conveying means, and the first conveying means and the second conveying means are provided. Since the toner carrying force between the first carrying means and the second carrying means is improved, the toner flows smoothly without being accumulated between the first carrying means and the second carrying means.

Further, in the third invention, the third conveying means is disposed in the toner circulating portion between the first conveying means and the second conveying means, and the third conveying means causes the first conveying means to move the first conveying means. Since the toner is conveyed in a direction at a right angle to the toner conveying direction of the first conveying means or the second conveying means, the toner is conveyed to a site downstream of the first conveying means and the second conveying means in the conveying direction. The toner can be efficiently and smoothly transported to the upstream side of the second transport means and the first transport means in the transport direction.

In the fourth aspect of the invention, since the vibrating member is arranged at the corner of the second carrying means in the carrying direction, there is no place where the toner accumulates at the corner. Further, since the vibrating member vibrates to repel the toner adhering to the surface of the vibrating member and push out the toner existing at the corners from the corners, the toner smoothly flows out from the corners.

[0026]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Embodiment 1 FIGS. 1 and 2 show a developing device according to Embodiment 1 of the present invention. This developing device includes a developing roll 1, a layer thickness regulating blade 6 that is in contact with the developing roll 1, a first conveying unit 2 that is rotatably arranged in parallel with the developing roll 1, and a first conveying unit. Second conveying means 3 arranged rotatably in parallel with the developing roll 1 with 2 interposed therebetween, and the developing roll 1, the layer thickness regulating blade 6, the first conveying means 2 and the second conveying means. A latent image is formed by a housing 4 that holds the means 3 and a toner cartridge (not shown) that is detachably attached to the housing 4. The developing roll 1 faces the latent image carrier such as a photoconductor. A toner image is formed on the carrier.

The toner cartridge has an average particle size of 7
A black magnetic toner of ˜11 μm is stored.

The developing roll 1 comprises a mag roll 1b which adsorbs the magnetic toner and a sleeve 1a which rotates around it. Further, the mag roll 1b has a structure shown in FIG.
As shown in FIG.
The S ₁ pole, the N ₁ pole, the S ₂ pole, the S ₃ pole and the N ₂ pole are formed in order in the rotation direction of the sleeve 1a (counterclockwise in FIG. 2) from the position abutting against.

In the housing 4, the first conveying means 2 is provided.
A first transfer chamber 5a formed around the first transfer chamber 5a, the developing roller 1 being exposed on one side, a second transfer chamber 5b formed around the second transfer unit 3, and a first transfer chamber 5a. A pair of openings 5c communicating with the second transfer chamber 5b at both ends thereof,
5d, a partition plate 5f formed between the pair of openings 5c, 5d, and one end of the first transfer chamber 5a, which communicates with the toner supply chamber 5 to which the toner is supplied from the toner cartridge.
The toner circulation unit 5 is formed by e. Also,
A pressure sensor 7 is disposed on the side surface of the second transfer chamber 5b, and the supply of toner from the toner cartridge is controlled according to the output of the pressure sensor 7.

The first transfer means 2 includes a first transfer chamber 5
a first rotation shaft 2a having a length from a to the toner supply chamber 5e and rotatably held in the housing 4, and formed around the first rotation shaft 2a located in the toner supply chamber 5e, A spiral blade 2c that conveys the toner supplied to the toner supply chamber 5e to the first transfer chamber 5a and a first rotary shaft 2a that is located in the first transfer chamber 5a are formed around the first blade 2c. It is composed of a spiral agitator 2b that transports the toner in the transport chamber 5a in one direction.

As shown in FIGS. 3 and 4, the second transfer means 3 has a length that extends over the entire width of the second transfer chamber 5b and is rotatably held by the housing 4. It comprises a rotating shaft 3a and a spiral agitator 3b which is formed around the second rotating shaft 3a and which carries the toner in the second carrying chamber 5b in the direction opposite to that of the first carrying means 2.

The spiral agitators 2b and 3 are also provided.
b is a wire having a wire diameter of 2 mm, a radius of 10 mm and a winding number of 0.4
It is formed in a spiral shape with a turn / cm. In addition, the spiral agitator 2b of the first transport means 2 is
When the first rotary shaft 2a is rotated in a predetermined direction (clockwise in FIG. 2), the toner in the first transfer chamber 5a is attached to the first rotary shaft 2a in such a direction that the toner can be transferred in the one direction. The spiral agitator 3b of the second transport means 3 is configured such that when the second rotary shaft 3a rotates in the same direction as the first rotary shaft 2a (clockwise in FIG. 2), the toner in the second transport chamber 5b Is attached to the second rotating shaft 3a in such a direction as to be able to be conveyed in the opposite direction. The first transporting means 2 and the second transporting means 3 are driven by a driving means (not shown) to rotate.

In the present embodiment, as shown in FIG. 1, projections 4a and 4d are formed on the side surfaces of the toner circulating portion 5 between the first conveying means 2 and the second conveying means 3, respectively. , A pair of corners 4b and 4c formed by the side surface of the toner circulating portion 5 through which the second rotary shaft 3a penetrates and the side surface of the toner circulating portion 5 adjacent to the side surface, that is, the conveyance of the second conveying means 3. A pair of corners 4b and 4c in the direction are formed on the curved surface. Therefore, the first transport means 2 and the second transport means 3
And the corners 4b and 4c have no place where toner is accumulated.

Between the first conveying means 2 and the second conveying means 3, a side surface of the toner circulating portion 5 located on the downstream side (hereinafter referred to as the inner side) of the first conveying means 2 in the conveying direction (see FIG. The protrusion 4a formed on the right side surface in Fig. 1) is formed in a tapered shape with a height of 3 to 6 mm, that is, both sides of the side surface facing the first conveying means or the second conveying means circulate the toner. It is formed so as to cross the side surface of the portion obliquely, the surface thereof is coated with Teflon, and the tip portion is arranged so as to be located in the opening. For that reason,
The toner flows smoothly near the surface of the protrusion 4a.

Between the first conveying means 2 and the second conveying means 3, the side surface of the toner circulating portion 5 located on the downstream side of the second conveying means 3 in the conveying direction (hereinafter referred to as the outer side) (see FIG. The protrusion 4d formed on the right side surface in FIG. 1 does not have the side surface of the first conveying unit, so that one side surface is formed in a wedge shape continuous with the side surface of the toner supply chamber 5e, and at the same time as the second side surface. The side surface facing the conveying means is formed so as to obliquely intersect the side surface of the toner circulating portion, and the surface thereof is coated with Teflon. Therefore, the toner flows smoothly near the surface of the protrusion 4d.

The curved surfaces formed on the pair of corners 4b and 4c are, as shown in FIG. 5, at both ends of the second conveying means 3 from a position 4 to 5 mm from the position where the second rotating shaft 3a penetrates. Of the radius of curvature of 7 to 8 mmR from the position where the spiral passes through to the position closer to the center of the second conveying means 3.
Is a curved surface formed on the second conveying member 3b, and the distance between the second conveying member 3b and the other toner circulating portion is smaller. The surface is coated with Teflon. Therefore, in the inner corner portion 4b, the direction of the toner is conveyed by the second conveying means 3, that is, the direction is orthogonal, without attenuating the conveying force of the toner conveyed from the inner opening 5c direction due to the curved surface. Since the toner can smoothly flow in the vicinity of the corner 4b, the direction of the toner can be smoothly changed at the outer corner 4c without attenuating the toner carrying force of the second carrying means 3 due to the curved surface. Since it can be changed in the direction of the outer opening 5c, that is, in the direction orthogonal to the opening 5c, the toner flows smoothly in the vicinity of the corner 4c.

Even if the toner is circulated in the toner circulating unit 5 while changing the temperature and the humidity, the toner is circulated between the first conveying unit 2 and the second conveying unit 3 and at the corners 4b and 4c. Is not accumulated, and agglomerated toner is not generated even after an appropriate time. Further, since no toner pool is formed in the toner circulation unit 5, the toner waste can be reduced accordingly.

Example 2 Instead of forming curved surfaces on the pair of corners 4b and 4c, as shown in FIG.
As shown in, the same as Example 1 except that the vibrating member 8 is arranged at the pair of corner portions 4b and 4c and the recess 9 for fixing the vibrating member 8 is formed in the housing 4.

As shown in FIG. 7, the vibrating member 8 has a substantially rectangular shape with a curved portion 8b formed in the center thereof, and a through hole 8c through which the second rotating shaft 3a penetrates at one end thereof.
Is formed, and its surface is coated with Teflon. Then, the leaf spring member 8a is inserted into the through hole 8c and the second rotary shaft 3a.
And the other end side end is locked in the recess 9 of the housing 4, and the back surface of the leaf spring member 8a and the housing 4 are fixed with double-sided tape and arranged on the corners 4b and 4c. It Further, the curved portion 8b is formed in such a size that the spiral end portion of the second conveying means 3 comes into contact with the spiral portion at one degree of rotation, and thereby the entire leaf spring member 8a is distorted.

Then, when the toner was circulated in the toner circulating unit 5 while changing the temperature and the humidity, Example 1
In addition to the above effect, the leaf spring member 8a vibrates with the rotation of the second conveying means 3, and the leaf spring member 8a is repelled when the second conveying means 3 is separated, and the impact thereof causes the leaf spring member 8a. The toner attached to the surface of 8a is blown off,
The toner does not agglomerate on the surface of the leaf spring member 8a.

It should be noted that instead of using the substantially rectangular leaf spring member 8a having the curved portion 8b formed in the central portion, as shown in FIG.
As shown in, the rectangular leaf spring member 8d (for example,
A PET film having a thickness of about 0.05 to 0.2 mm is used, and the second rotary shaft 3 is attached to the second rotary shaft 3a.
By disposing a spring wire 8e (for example, a diameter of about 0.1 to 0.3 mm) having a length that abuts so that the entire leaf spring member 8d is distorted each time a rotates, the second conveyance Since the leaf spring member 8d can be vibrated with the rotation of the means 3, the same effect can be obtained. When the second transport member is formed by a spiral agitator, its end is extended and the spring wire 8e is extended.
May be used as.

Embodiment 3 As shown in FIGS. 9 and 10, instead of forming the protrusion 4a on the inner side surface of the toner circulating portion 5 between the first conveying means 2 and the second conveying means 3, as shown in FIGS. Example 1 except that the third conveying unit 10 including the paddle 10a is arranged in the toner circulating unit 5 between the first conveying unit 2 and the second conveying unit 3.
Is the same as

As shown in FIG. 11, the paddle 10a is composed of a third rotating shaft 10b and four third conveying members 10c arranged at 90 ° intervals around the third rotating shaft 10b. It is coated with Teflon. The third rotating shaft 10b is rotatably held by the housing 4, and is driven by a driving unit (not shown) to rotate.
The third conveying member 10c has a length of 7 to 8 mm and a width of 15 to
It is made of a PET film having a rectangular shape of 25 mm and having a through hole formed in the center thereof for adjusting the conveying force.

Then, the toner was circulated in the toner circulation portion 5 while changing the temperature and the humidity, and
In addition to the above effect, the toner can be efficiently discharged from the opening 5c on the inner side, so that a mountain of toner is not formed on the inner side after copying a large number of small-sized originals.
Immediately thereafter, even if a large-sized original is copied, there is no unevenness in the inner and outer development densities.

Embodiment 4 In this embodiment, as shown in FIG. 12, the first conveying means 2 is used.
A protrusion 4d similar to that of the first embodiment is formed on the outer side surface of the toner circulating portion 5 between the first transporting means 2 and the second transporting means 3, and the toner between the first transporting means 2 and the second transporting means 3 is formed. The third embodiment is the same as the second embodiment except that the third conveying means 10 including the conveyor belt 10d is arranged inside the circulation portion 5, and the vibrating member 8 is arranged at the pair of corner portions 4b and 4c.

The conveyor belt 10d is shown in FIGS.
As shown in FIG. 4, the first rotary shaft 2a and the second rotary shaft 3a
It is composed of an endless belt 10e stretched between and, and 5 to 10 third conveying members 10c arranged at equal intervals around the endless belt 10e, the surface of which is coated with Teflon.

The vibrating member 8 is, as shown in FIG.
It has a rectangular shape, and the second rotating shaft 3a is provided on one end side thereof.
PET film 8f having through holes formed therethrough
Is disposed between the PET film 8f and the housing 4, and is bent by the toner transporting force of the first transporting means 2 and the third transporting means 10. If there is no toner transporting force, the PET film 8f is removed. It is composed of a compression spring 8g that pushes back to a position where it comes into contact with the spiral agitator 3b of the second conveying means, and the surface of the PET film 8f is coated with Teflon.

Then, when the toner was circulated in the toner circulation unit 5 while changing the temperature and the humidity, Example 3
In addition to the effect of 1st conveyance means 2 and 3rd conveyance means 1
When the PET film 8f vibrates with the rotation / stop of 0, the PET film 8f comes into contact with the spiral agitator 3b of the second conveying means when pushed back, and the impact causes the toner adhered to the surface of the PET film 8f. Since the toner is repelled, the toner does not agglomerate on the surface of the PET film 8f.

[0050]

As described above, according to the first invention, the protrusion is formed on the side surface of the toner circulating portion between the first conveying means and the second conveying means, and the protrusion is formed. A central portion protruding toward the inside of the toner circulating portion; and an inclined surface portion inclined from the central portion toward the side surfaces of the toner circulating portion on the first conveying means side and the second conveying means side. Since the place where the toner is accumulated between the conveying means and the second conveying means is eliminated and the toner is made to flow smoothly in the vicinity of the surface of the protrusion, it is possible to arrange the toner between the first conveying means and the second conveying means. The toner is allowed to flow without accumulating, and the toner is not agglomerated between the first conveying means and the second conveying means.

According to the second aspect of the invention, the corner portion in the carrying direction of the second carrying means is formed into a curved surface, and the curved surface causes a carrying force in the direction orthogonal to the carrying direction of the toner. Since the toner is formed in a shape so as to eliminate the place where the toner collects in the corners and allows the toner to flow smoothly near the curved surface, the toner flows in the corners without collecting, and It does not agglomerate the toner.

According to the third invention, the third conveying means is arranged in the toner circulating portion between the first conveying means and the second conveying means, and the first conveying means and the second conveying means are arranged. Since the toner is allowed to flow without accumulating between the first conveying means and the second conveying means, the toner is allowed to flow without accumulating between the first conveying means and the second conveying means. The toner is not agglomerated between the second conveying means.

Further, in the third invention, the third conveying means is arranged in the toner circulating portion between the first conveying means and the second conveying means, and the first conveying means and the second conveying means are provided. Since the toner conveyed to the downstream side of the conveying direction of the conveying means can be efficiently and smoothly conveyed to the upstream side of the conveying direction of the second conveying means and the first conveying means, The toner does not accumulate at the downstream side of the conveying means of the second conveying means and the conveying means of the second conveying means, and even if a large-sized original is copied immediately after a large number of small-sized originals are copied, the image quality of the toner image is poor. Does not occur.

According to the fourth aspect of the invention, the vibrating member is arranged at the corner of the second carrying means in the carrying direction, and the vibration of the vibrating member allows the toner to flow without being accumulated at the corner. At the corners, the toner flows without being accumulated, and the toner does not agglomerate at the corners.

[Brief description of drawings]

FIG. 1 is a sectional view of a developing device according to a first embodiment of the present invention.

FIG. 2 is a side sectional view of the developing device of FIG.

FIG. 3 is a front view of a second carrying unit used in the developing device of FIG.

FIG. 4 is a side view of the second transport means of FIG.

FIG. 5 is an enlarged view of a corner portion of the developing device in FIG.

FIG. 6 is an enlarged view of a corner portion of the developing device according to the second embodiment of the present invention.

7 is a perspective view of a vibrating member used in the developing device of FIG.

FIG. 8 is a modification of the developing device according to the second embodiment (corner enlarged view).

FIG. 9 is a sectional view of a developing device according to a third embodiment of the present invention.

FIG. 10 is a side sectional view of the developing device in FIG.

11 is a perspective view of a third transport member (paddle) used in the developing device in FIG.

FIG. 12 is a sectional view of a developing device according to a fourth embodiment of the present invention.

13 is a side sectional view of the developing device shown in FIG.

14 is a perspective view of a third conveying member (conveying belt) used in the developing device of FIG.

FIG. 15 is an enlarged view of a corner portion of the developing device in FIG.

FIG. 16 is a sectional view of a conventional developing device.

[Explanation of symbols]

1: developing roll, 2: first conveying means, 3: second conveying means, 4: housing, 4a, 4d: protrusions, 4b, 4
c: corner portion, 5: toner circulation portion, 8: vibrating member, 10: third conveying means.

Claims (4)

[Claims] 1. A developing roll arranged to face the latent image carrier, a first conveying unit arranged in parallel with the developing roll and rotating to convey toner in one direction, and a first conveying unit. A second conveying unit that is arranged in parallel with the developing roller with the unit interposed therebetween and rotates to convey the toner in the opposite direction to the first conveying unit; the developing roller, the first conveying unit, and the second conveying unit. And a housing for holding the transporting means, the toner circulating part having an opening formed on the periphery of the first transporting means and the second transporting means and having the developing roll exposed on one side surface. In the formed one-component developing device, a protrusion is formed on the side surface of the toner circulating portion between the first conveying unit and the second conveying unit, and the protrusion is projected toward the toner circulating unit. The central part that has been A one-component developing device having an inclined surface portion inclined toward the side surface of the toner circulation portion on the side of the second conveying unit. 2. A developing roller arranged to face the latent image carrier, a first conveying means arranged in parallel with the developing roller and rotating to convey toner in one direction, and a first conveying means. A second conveying unit that is arranged in parallel with the developing roller with the unit interposed therebetween and rotates to convey the toner in the opposite direction to the first conveying unit; the developing roller, the first conveying unit, and the second conveying unit. And a housing for holding the transporting means, the toner circulating part having an opening formed on the periphery of the first transporting means and the second transporting means and having the developing roll exposed on one side surface. In the formed one-component developing device, the corner portion in the transport direction of the second transport means is formed into a curved surface, and the curved surface causes a transport force in a direction orthogonal to the toner transport direction. Of a one-component system characterized by being shaped like Development device. 3. A developing roll arranged to face the latent image carrier, a first conveying unit arranged in parallel with the developing roll and rotating to convey toner in one direction, and a first conveying unit. A second conveying unit that is arranged in parallel with the developing roller with the unit interposed therebetween and rotates to convey the toner in the opposite direction to the first conveying unit; the developing roller, the first conveying unit, and the second conveying unit. And a housing for holding the transporting means, the toner circulating part having an opening formed on the periphery of the first transporting means and the second transporting means and having the developing roll exposed on one side surface. In the formed one-component developing device, the one-component developing device is characterized in that the third conveying means is arranged in the toner circulating portion between the first conveying means and the second conveying means. apparatus. 4. A developing roll arranged to face the latent image carrier, a first conveying unit arranged in parallel with the developing roll and rotating to convey toner in one direction, and a first conveying unit. A second conveying unit that is arranged in parallel with the developing roller with the unit interposed therebetween and rotates to convey the toner in the opposite direction to the first conveying unit; the developing roller, the first conveying unit, and the second conveying unit. And a housing for holding the transporting means, the toner circulating part having an opening formed on the periphery of the first transporting means and the second transporting means and having the developing roll exposed on one side surface. In the formed one-component developing device, a one-component developing device is characterized in that a vibrating member is arranged at a corner of the second conveying means in the conveying direction.