JP2000250308A - Developing device and image forming device - Google Patents

Abstract

(57) Abstract: The gap between first and second regulating members and a developer carrier and the fluidity of the developer are optimized, and the toner concentration of the developer in the longitudinal direction of the developer carrier is made uniform. The present invention provides a developing device that can be developed. SOLUTION: The fluidity of a developer 15 is set to 10 seconds or more and 30 seconds or less, and a first gap Gd = 0.25 to 0.45 mm, a second gap PreGd = 0.7 to 1.3 mm, and Gd * Pr.
eGd is set in the range of 0.2 to 0.3. As a result, even when gravity and a magnetic field act on the developer in the developer accommodating chamber 13, the circulation state of the developer is not partially changed, unevenness in the movement of the developer is eliminated, and the amount of toner taken in is reduced. The difference is eliminated so that the toner concentration of the developer does not become uneven.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a two-component developer containing a toner and a magnetic carrier, regulates the amount of developer on a developer carrier with a regulating member, and controls the amount of developer on the developer carrier. The present invention relates to a developing device that adjusts the toner concentration by self-controlling the taking-in of a developer by a change in the toner concentration, and an image forming apparatus using the developing device.

[0002]

2. Description of the Related Art Conventionally, as a developing device of this type, the amount of a two-component developer carried and conveyed by a developer carrier having a magnetic field generating means therein is regulated by a regulating member. 2. Description of the Related Art There is known a developing device in which toner is supplied from a toner storage unit to a developer storage chamber by increasing or decreasing the volume of the stored developer. In this developing device, a developer moving layer that is carried and conveyed by a developer carrier and a developer circulating layer that can circulate in the developer accommodating chamber are generated, and toner is taken in by the movement of the developer. I have. Although such a developing device does not require the toner density detecting means,
Active and inactive areas of the developer in the developer container,
Alternatively, there is a problem that the amount of developer taken in by the developer is different between a portion where the amount of the developer is large and a portion where the amount of the developer is small, so that the toner density becomes partially unstable. For this reason, in the developing device described above, a second regulating member is provided on the upstream side in the transport direction of the developer on the developer carrying member with respect to the regulating member regulating the amount of the developer. When the toner concentration of the developer increases and the layer thickness of the developer increases, the gap between the second carrier and the developer carrier is set so that the second regulating member regulates the passage of the increased amount of the developer. An apparatus has been proposed (JP-A-9-197833). In this developing device, the second regulating member regulates the passage of the increased developer, and the regulated developer controls the taking-in of the toner, so that the toner supply can be constantly controlled at a constant level. Adjustments can be made.

[0003]

However, even with the provision of the second regulating member as described above, it is difficult to eliminate the uneven image density due to the difference in the amount of toner taken in by the developer in the developer accommodating chamber. found. This is presumed to be because gravity and a magnetic field act on the developer in the developer accommodating chamber, and the developer circulation state partially changes under the influence of the gravity and the magnetic field. When the developer circulation state partially changes, a difference in the amount of toner taken in is caused by uneven movement of the developer, and uneven toner concentration of the developer occurs. For this reason, the toner density in the developer in the longitudinal direction of the developer carrier becomes non-uniform, and as a result, density unevenness occurs in the toner image formed by the image forming apparatus using the developing device.

The present invention has been made in view of the above background, and as a first object, a partial change in a developer circulation state due to the influence of gravity and a magnetic field acting on a developer in a developer accommodating portion. An object of the present invention is to provide a developing device which can prevent toner density unevenness from occurring due to a difference in the amount of toner taken in due to uneven movement of the developer, and can make the toner density of the developer uniform in the longitudinal direction of the developer carrier. . Second
The purpose of this method is to eliminate the partial change of the developer circulation state due to the influence of gravity and magnetic field acting on the developer in the developer container, and to cause uneven toner density due to the difference in the amount of toner taken in by the uneven movement of the developer. It is an object of the present invention to provide an image forming apparatus capable of making the toner density of the developer uniform in the longitudinal direction of the developer carrying member, and completely eliminating the density unevenness of the toner image.

[0005]

In order to achieve the first object, according to the first aspect of the present invention, there is provided a magnetic image generating means opposed to a latent image carrier for carrying a latent image, A developer carrying member that carries and transports a two-component developer including a toner and a magnetic carrier; a first regulating member that regulates an amount of the developer carried and transported by the developer carrying member; A developer accommodating portion for accommodating the developer scraped off by the regulation of the first regulating member, and a toner accommodating portion adjacent to the developer accommodating portion and accommodating toner for supplying toner to the developer accommodating portion. And a developing unit for controlling replenishment of toner from the toner storage unit to the developer storage unit at a position upstream of the first developer regulating member in the direction of transport of the developer on the developer carrier. Regulating member for regulating the amount of the developer on the developer carrier Wherein the toner is supplied from the toner storage section to the developer storage section based on a change in the toner concentration of the developer regulated by the second restriction member, and the toner intake of the developer is controlled. A developing device for developing the latent image on the latent image carrier with the developer of the developer carrier regulated by the first regulating member;
The first gap between the first regulating member and the developer carrier, the second gap between the second regulating member and the developer carrier, and the product of the first gap and the second gap are respectively predetermined. A developer having a range and a fluidity of the developer within a predetermined range.

Here, the relationship between the fluidity of the developer and the toner concentration will be described. When the fluidity of the developer is very good, the developer in the developer accommodating chamber is pressed together with the toner by, for example, an agitator as a toner replenishing member, so that the junction between the developer moving layer and the developer circulating layer is first. It becomes easy to move to the vicinity of the regulating member. For this reason, it becomes easier for the developer to take in the toner partially, and the toner density is partially increased. Therefore, soiling-like unevenness easily occurs. On the other hand, when the fluidity of the developer is very poor, the junction between the developer moving layer and the developer circulating layer is easily moved to the vicinity of the second regulating member, and the interface between the two layers is a developer carrier. It is formed at a greater distance. Therefore, the developer is not actively circulated, and the toner may not be partially replenished. As a result, the toner density is partially reduced.

Next, the relationship between the first gap, the second gap, and the toner concentration in the developer accommodating chamber will be described. If the first gap and the second gap are both wide, the amount of toner entering the developer accommodating chamber becomes large, and the first gap and the second gap have an average toner density (average toner density in the longitudinal direction). Value). However, if the first gap and the second gap are too wide, the thickness of the developer moving layer becomes too large and the thickness of the developer circulation layer becomes small. Is not actively performed, and uneven toner density is likely to occur. When both the first gap and the second gap are narrow, the amount of the toner 11 that enters the developer accommodating chamber becomes small, and the first gap and the second gap have an average toner density (toner density in the longitudinal direction). Average). However, if the first gap and the second gap are too small, the thickness of the developer moving layer becomes too small,
It becomes difficult to actively take in the toner into the developer, and the toner density unevenness easily occurs. From the above description,
In order to eliminate toner density unevenness, when the first gap is wide, the second gap is narrowed, and when the first gap is narrow, the second gap is narrowed.
It is better to widen the second gap.

According to the present invention, the fluidity of the developer is optimized within a predetermined range so that the developer can be circulated in the developer accommodating portion satisfactorily. Further, the first gap between the developer carrying member and the first regulating member, the second gap between the developer carrying member and the second regulating member, and the product of the first gap and the second gap are optimized to predetermined ranges. , Together with the first gap and the second gap,
The relationship between the widths of the two gaps is also optimized, so that the circulation of the developer in the developer accommodating section and the taking-in of the toner into the developer accommodating chamber are required. Thereby, even if the developer in the developer accommodating portion is affected by gravity and a magnetic field, a partial change in the developer circulation state is prevented.

According to a second aspect of the present invention, in the developing device of the first aspect, the first regulating member and the developer carrying member are connected in a first direction.
When Gd is the gap, PreGd is the second gap between the second regulating member and the developer carrier, and Gd * PreGd is the product of the first gap and the second gap, Gd = 0.
25-0.45 mm, PreGd = 0.7-1.3 mm
Gd * PreGd = 0.2-0.3, and the developer is a developer outflow time (toner concentration 10w) according to JIS Z2502 (a method for measuring the fluidity of metal powder).
60 g of t% developer in a funnel having a hole diameter of 5 mm
(The time from the start to the end of the outflow when the developer is dropped by its own weight from the hole) is 10 seconds or more and 30 seconds or less.

According to the second aspect of the present invention, when the flow time of the developer is 10 seconds or more and 30 seconds or less, Gd = 0.25-0.
45 mm, PreGd = 0.7-1.3 mm, Gd *
PreGd = 0.2-0.3. Table 1 shows that the image forming apparatus to which the developing device of the present invention can be applied has a G
FIG. 9 shows the results of examining the state of toner density unevenness in a developed image in various combinations of d * PreGd and the flow time of the developer.

[Table 1] As shown in this table, it was confirmed that when the fluidity was 10 seconds or more and 30 seconds or less, and in the range of Gd * PreGd = 0.2-0.3, toner density unevenness did not occur. In the present invention, Gd = 0.25 to 0.45 mm, PreGd =
0.7 to 1.3 mm, and Gd * PreGd = 0.2 to
0.3 and the outflow time of the developer is set to 10 seconds or more and 30 seconds or less, and the toner density of the developer in the longitudinal direction of the developer carrier is made uniform within the range where the density unevenness shown in Table 1 does not occur. It can be so.

According to a third aspect of the present invention, there is provided a latent image carrier for carrying a latent image, and a magnetic field generating means opposed to the latent image carrier and provided therein. A developer carrying member that carries and conveys a two-component developer including a toner and a magnetic carrier, and a first regulating member that regulates the amount of the developer carried and carried by the developer carrying member; A developer accommodating portion for accommodating the developer scraped off by the regulation of the first regulating member; and a toner adjoining the developer accommodating portion and accommodating toner for replenishing the developer accommodating portion with toner. An accommodating portion, for controlling toner replenishment from the toner accommodating portion to the developer accommodating portion at a position upstream of the first developer regulating member in a direction in which the developer is conveyed on the developer carrying member; Second regulating member for regulating the amount of the developer on the developer carrier Wherein the toner is supplied from the toner storage section to the developer storage section based on a change in the toner concentration of the developer regulated by the second restriction member, and the toner intake of the developer is controlled. And a developing device for developing the latent image on the latent image carrier with the developer of the developer carrier regulated by the first regulating member. The first gap with the developer carrier, the second gap between the second regulating member and the developer carrier, and the product of the first gap and the second gap are each within a predetermined range, and the developer is The present invention is characterized in that a gap between the carrier and the latent image carrier is set within a predetermined range, and a developer is used in which the fluidity of the developer is within a predetermined range.

According to the third aspect of the present invention, the first gap between the developer carrier and the first regulating member, the second gap between the developer carrier and the second regulating member, and the first gap and the second gap. And the fluidity of the developer is adjusted to a predetermined range, so that the developer in the developer accommodating portion is in a state where the developer circulates even if the developer is affected by gravity and a magnetic field. The necessary development ability is ensured without causing any change. In addition to this, the gap between the latent image carrier and the developer carrier is adjusted to a predetermined range, and the latent gap generated when the first gap is too large with respect to the gap between the latent image carrier and the developer carrier. The overflow of the developer is prevented in the gap between the image carrier and the developer carrier.

According to a fourth aspect of the present invention, in the image forming apparatus of the third aspect, the first gap between the first regulating member and the developer carrying member is Gd, and the second regulating member and the developer carrying member are arranged in a gap. Gd = PreGd, and the product of the first gap and the second gap is Gd * PreGd.
0.25 to 0.45 mm, PreGd = 0.7 to 1.3
mm, Gd * PreGd = 0.2-0.3, and the gap between the developer carrier and the latent image carrier is Gp
Where Gp = 0.3 to 0.4 mm, and the developer has a developer outflow time (toner concentration of 10 watts) according to JIS Z2502 (a method for measuring the fluidity of metal powder).
60 g of t% developer in a funnel having a hole diameter of 5 mm
(The time from the start to the end of the outflow when the developer is dropped by its own weight from the hole) is 10 seconds or more and 30 seconds or less.

According to the fourth aspect of the present invention, Gd = 0.2
5 to 0.45 mm, PreGd = 0.7 to 1.3 mm,
And Gd * PreGd = 0.2 to 0.3, and the outflow time of the developer is adjusted to 10 seconds or more and 30 seconds or less. As a result, even if the developer in the developer accommodating section is affected by gravity and a magnetic field, a partial change in the developer circulation state does not occur. In addition to this, the gap Gp between the developer carrier and the latent image carrier is optimized in the range of 0.3 to 0.4 to secure the necessary developing capacity and to ensure the required development capacity and the latent image carrier and the developer carrier. To prevent the developer from overflowing.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a developing device and an image forming apparatus using the developing device will be described below. In the image forming apparatus, a developing device, a charging device (not shown), an exposure device (not shown), a static elimination device (not shown), and the like are arranged around a drum-shaped photoconductor as a latent image carrier.

FIG. 1 is a schematic configuration diagram showing a main part of a developing device according to the present embodiment and an image forming apparatus using the developing device. A developing device 2 is provided beside a drum-shaped photoconductor (hereinafter, referred to as a “photoconductor drum”) 1, and the developing device 2 has a support case 3. The support case 3 has a wall 3 a and a substantially arc-shaped bottom 3 in a sectional view.
b, a projection 3c, a substantially arc-shaped bottom 3d, and a lid 3e, and the upper surface of the projection 3c extends from the bottom 3b side to the bottom 3d.
It has a slope of a predetermined length that is slightly lowered toward the d side. Above the bottom 3d of the support case 3, a developing sleeve 4 is rotatably disposed facing the photoreceptor drum 1, and the developing sleeve 4 serves as a magnetic field generating means fixed inside thereof. (Not shown) is provided. A first doctor blade 5 as a developer regulating member is attached to the cover 3e on the photosensitive drum 1 side, and the tip of the first doctor blade 5 is spaced at a predetermined distance from the outer peripheral surface of the developing sleeve 4. A second doctor blade 6 as a developer regulating member protrudes from the lid portion 3e so as to face the first doctor blade 5, and a tip side thereof is bent toward the center of the developing sleeve 4, and The tip is at a predetermined distance from the outer peripheral surface of the developing sleeve 4. A toner supply port 7 is provided between the lower surface of the bent portion of the second doctor blade 6 and the inclined surface of the projection 3c of the support case 3.

In the supporting case 3, a toner agitator 10 as a toner replenishing means driven by a driving means (not shown) is rotatably provided in a toner hopper 9 as a toner storage section partitioned by a second doctor blade 6. The toner agitator 10 feeds the toner 11 in the toner hopper 9 toward the toner supply port 7 while stirring the toner 11. First of support case 3
A developer accommodating chamber 13 as a developer accommodating section is formed between the doctor blade 5 and the second doctor blade 6, and the developer accommodating chamber 13 includes a developer 15 including a toner 11 and a magnetic carrier 14. Is housed. The developer accommodating chamber 13 is a space sufficient to circulate the developer 15 within a range where the magnetic force of the developing sleeve 4 can reach.

The operation of the developing device having the above configuration and the operation of the image forming apparatus using the developing device will be described. When the developer 15 as an initial agent is stored in the developer storage chamber 13 and the developing sleeve 4 is rotated, the developer 15
And a developer 15 magnetically attached to the surface of the developing sleeve 4 and a developer 15 accommodated in the developer accommodating chamber 13 without being magnetically attached to the developing sleeve 4. Developer 1 magnetically attached to the surface of developing sleeve 4
5 forms a developer moving layer, while the developer 15 not magnetically attached to the developing sleeve 4 forms a developer stagnation layer. When the developing sleeve 4 rotates in the direction of the arrow, the developer stagnation layer moves in the direction of the arrow due to the magnetic field of the magnet provided on the developing sleeve 4 and the frictional force generated between the developer moving layer by the weight of the magnetic carrier 14 and the like. The developer circulates and the developer stagnation layer becomes a developer circulating layer. Then, a merging point Y is formed at a point where the developer moving layer and the developer circulating layer merge, and an interface X is formed at the boundary (see FIG. 2).

Next, when the toner 11 is supplied into the developer accommodating chamber 13 from the toner hopper 9 through the toner supply port 7, the toner 11 is carried to the interface X. Due to the toner 11 carried to the interface X, the frictional force between the developer moving layer and the developer circulating layer is reduced, and the transport force for transporting the developer 15 in the developer circulating layer is reduced. As a result, the balance between the developer transporting force and the transport inhibiting force at the junction Y is broken, the position of the junction Y rises, and the developer moving layer becomes thicker. This developer thickening is applied to the developer 15 scraped off by the second doctor blade 6 on the upstream side of the second doctor blade 6.
Proceed until the pool is formed. The pool of the developer 15 is formed so as to close the toner supply port 7, and the toner supply from the toner supply port 7 is stopped. At this time, in the developer accommodating chamber 13, the toner density of the developer 15 is increased, so that the bulk of the developer 15 is increased. As a result, the space in the developer accommodating chamber 13 is reduced, and the movement of the developer circulation layer is reduced. Stops. As a result, the developer 15 on the developing sleeve 4 is
The toner density is always controlled to the upper limit. Developing sleeve 4
The developer 15 carried and transported by the developing sleeve 4
Is regulated to a predetermined thickness by an interval between the first doctor blade 5 and the first doctor blade 5, and is conveyed to a developing position facing the photosensitive drum 1. At the developing position, the electrostatic latent image on the photosensitive drum 1 is developed with the toner 11 of the developer 15 carried and transported by the developing sleeve 4, and a toner image is formed.

The toner density of the developer 15 on the developing sleeve 4 described above may become non-uniform due to the difference in the amount of toner taken into the developer 15 in the developer accommodating chamber 13. This is because the developer 15 in the developer accommodating chamber 13 has a partial change in the developer circulation state which is estimated to be caused by the action of gravity and a magnetic field, and a difference in the density of the developer 15 occurs. Due to the difference in the amount of toner taken in. For this reason, the developer 15 in the longitudinal direction of the developing sleeve 4 is
Becomes uneven. As a result, density unevenness occurs in the toner image. In order to solve the above-mentioned problem, the present inventor has set the developer fluidity, the gap between the first doctor blade and the developing sleeve 4 as Gd, and the gap between the second doctor blade 6 and the developing sleeve 4 as PreGd and Gd * PreGd. And the gap Gp between the developing sleeve 4 and the photosensitive drum 1 were examined.
Since the non-uniformity of the toner density of No. 5 was eliminated, and a favorable result of completely eliminating the density unevenness of the toner image was obtained, FIG.
This will be described with reference to FIGS. 3 and 4 and Table 1.

The fluidity of the developer will be described. Regarding the developer fluidity, as shown in FIG.
In the rheometer 2 (manufactured by Kuramochi Scientific Instruments) used in No. 02, the funnel 2 supported by the funnel support 20 was used.
60 g of the developer 15 having a toner concentration of 10 wt% is set in the receiver 1, and the developer is supplied through a hole having a diameter of 5 mm into the receiver 23 on the receiver base 22.
Time from the start to the end of the outflow (seconds)
Was measured.

When the fluidity of the developer 15 is very good, for example, when the developer outflow time is shorter than 10 seconds, the developer 15 in the developer accommodating chamber 13 is supplied to the toner 11 by the agitator 10 for supplying toner. At the same time, the junction Y between the developer moving layer and the developer circulating layer is easily moved to the vicinity of the first regulating member 5 by receiving the pressure. Therefore, as shown in FIG.
The take-up of the toner 11 by the developer 15 tends to be partially active, and the toner density is partially increased. Therefore, soiling-like unevenness easily occurs. On the other hand, when the fluidity of the developer 15 is very poor, for example, when the developer outflow time is longer than 30 seconds, the junction Y between the developer moving layer and the developer circulating layer is located near the second regulating member. It is easy to move and is formed at a position where the interface X between the two layers is far away from the developing sleeve 4. Therefore, as shown in FIG. 3, the developer 15 may not be actively circulated, and the toner 11 may not be partially replenished. As a result, the toner density is partially reduced. Therefore, it is easy to cause unevenness such as ID decrease.

Next, Gd and PreGd and Gd * P
The relationship of reGd will be described. Gd and PreGd
Are large, the amount of the toner 11 entering the developer accommodating chamber 13 increases, and these Gd and PreGd
Is the average toner density (average toner density in the longitudinal direction)
Work to raise the However, if Gd and PreGd are too wide, the thickness of the developer transfer layer becomes too large, and the thickness of the developer circulation layer becomes small.
The circulation of the developer 15 in the developer accommodating chamber 13 is not actively performed, and the toner density unevenness is likely to occur. When both Gd and PreGd are narrow, the amount of the toner 11 entering the developer accommodating chamber 13 decreases, and these Gd and PreGd lower the average toner density (the average value of the toner density in the longitudinal direction). Work like that. However, if Gd and PreGd are too narrow, the thickness of the developer transfer layer becomes too small, so that it is difficult for the developer 15 to take in the toner 11 actively, and the toner density unevenness easily occurs. From the above description, in order to eliminate toner density unevenness, when Gd is wide, Pr
If eGd is narrow and Gd is narrow, PreGd should be widened. Specifically, as shown in Table 1,
When the fluidity of the developer 15 is 10 seconds or more and 30 seconds or less, Gd =
0.25 to 0.45 mm, PreGd = 0.7 to 1.3
mm and Gd * PreGd = 0.2-0.3, the circulation state of the developer partially changes even if gravity and a magnetic field act on the developer 15 in the developer accommodating chamber 13. do not do. Therefore, there is no unevenness in the movement of the developer, and there is no difference in the amount of toner taken in, so that unevenness in the toner density of the developer does not occur. Therefore, the toner concentration of the developer in the longitudinal direction of the developing sleeve 4 can be made uniform.

As for the gap Gp between the photosensitive drum 1 and the developing sleeve 4, when the fluidity of the developer 15 is 10 seconds or more and 30 seconds or less, Gd = 0.25 to 0.45 mm, Pr
When eGd = 0.7 to 1.3 mm, Gd * PreGd =
When it is in the range of 0.2 to 0.3, Gp = 0.3 to 0.3.
Set to 4 mm. When the gap Gp between the photosensitive drum 1 and the developing sleeve 4 is set in this manner, the developer accommodating chamber 13
Even when gravity and a magnetic field act on the developer 15 inside, the circulating state of the developer does not partially change, the necessary developing capability can be secured, and the Gd is too wide with respect to Gp. Overflow of the developer can be prevented in the gap between the photosensitive drum 1 and the developing sleeve 4. Therefore, the toner density of the developer in the longitudinal direction of the developing sleeve 4 can be made uniform, and the density unevenness of the toner image can be eliminated.

[0025]

According to the developing device of the first and second aspects, even if the developer in the developer accommodating section is affected by gravity and a magnetic field, a partial change in the developer circulation state can be prevented. Since the movement of the developer is not uneven, there is no difference in the amount of toner taken in by the developer, and no uneven toner density occurs. Therefore, there is an excellent effect that the toner concentration of the developer in the longitudinal direction of the developer carrier can be made uniform.

In particular, according to the developing device of the second aspect, the first gap, the second gap, and the specific gap for the developing device capable of equalizing the toner concentration of the developer in the longitudinal direction of the developer carrier. There is an excellent effect that the product of the first gap and the second gap and the fluidity of the developer can be presented.

According to the image forming apparatus of claims 3 and 4,
Even if the developer in the developer accommodating section is affected by gravity and a magnetic field, a partial change in the developer circulation state does not occur, so that the necessary developing capacity is secured. In addition, the latent image carrier and the developer carrier Since the overflow of the developer is prevented in the gap, the unevenness of the movement of the developer is not generated, so that there is no difference in the amount of toner taken in by the developer, and the toner density is not uneven. Therefore, there is an excellent effect that the toner concentration of the developer in the longitudinal direction of the developer carrying member can be made uniform and the density unevenness of the toner image can be eliminated.

In particular, according to the image forming apparatus of the fourth aspect,
Specific first and second gaps, the first gap and the first gap for an image forming apparatus capable of equalizing the toner concentration of the developer in the longitudinal direction of the developer carrying member and eliminating unevenness in the density of the toner image. There is an excellent effect that the product of the two gaps, the fluidity of the developer, and the gap between the developer carrier and the latent image carrier can be presented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating a developing device according to an embodiment.

FIG. 2 is an explanatory diagram illustrating a circulation motion of a developer in the developer accommodating chamber.

FIG. 3 is an explanatory diagram illustrating a circulation motion of the developer in the developer accommodating chamber.

FIG. 4 is a view for explaining a flow rate measuring device used in JIS Z2502.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photosensitive drum 2 developing device 3 support case 4 developing sleeve 5 first doctor blade 6 second doctor blade 7 toner supply port 9 toner hopper 10 agitator 11 toner 13 developer accommodating chamber 14 carrier 15 developer 20 funnel 21 funnel 22 receiver stand 23 receiver

Claims (4)

[Claims] A developer carrying member which faces a latent image carrying member for carrying a latent image, has a magnetic field generating means therein, and carries and transports a two-component developer containing a toner and a magnetic carrier; ,
A first regulating member that regulates an amount of the developer carried and conveyed by the developer carrier, and a developer accommodating portion that accommodates the developer scraped off by regulation of the first regulating member; A toner storage unit that is adjacent to the developer storage unit and stores toner to supply toner to the developer storage unit;
The developer carrier for controlling toner replenishment from the toner accommodating section to the developer accommodating section at a position upstream of the first developer regulating member in the direction of transport of the developer on the developer carrier. A second regulating member for regulating the amount of the developer above, wherein the toner is transferred from the toner accommodating portion to the developer accommodating portion based on a change in the toner concentration of the developer regulated by the second regulating member. Is supplied, and taking-in of the developer is controlled, and the developing device develops the latent image on the latent image carrier with the developer on the developer carrier regulated by the first regulating member. A first gap between the first regulating member and the developer carrier, a second gap between the second regulating member and the developer carrier, and a product of the first gap and the second gap, respectively. A predetermined range, and the fluidity of the developer A developing device which is characterized by using a developer comprising a predetermined range. 2. The developing device according to claim 1, wherein the first gap between the first regulating member and the developer carrier is G.
d, when the second gap between the second regulating member and the developer carrier is PreGd, and the product of the first gap and the second gap is Gd * PreGd, Gd = 0.25 to Gd = 0.25.
0.45 mm, PreGd = 0.7-1.3 mm, G
d * PreGd = 0.2 to 0.3, and the developer is a developer outflow time according to JIS Z2502 (a method for measuring the fluidity of metal powder). A developing apparatus wherein 60 g is set on a funnel having a hole diameter, and the time from the start to the end of the outflow of the developer from the hole by its own weight is 10 seconds or more and 30 seconds or less. 3. A latent image carrier for carrying a latent image, and a magnetic field generating means inside the latent image carrier, which carries a two-component developer containing a toner and a magnetic carrier. A developer carrying member to be conveyed, a first regulating member for regulating an amount of the developer carried and carried by the developer carrying member, and a developer scraped off by regulation of the first regulating member. A developer accommodating portion for accommodating, a toner accommodating portion adjacent to the developer accommodating portion and accommodating toner for replenishing the developer accommodating portion with the toner, A second regulating portion of the amount of the developer on the developer carrier to control a toner supply from the toner accommodating portion to the developer accommodating portion on an upstream side in a transport direction of the developer on the carrier; A regulating member, and the developer regulated by the second regulating member. The toner carrier is replenished from the toner containing section to the developer containing section based on a change in toner concentration, and the taking-in of the developer is controlled, and the developer carrier is regulated by the first regulating member. A developing device for developing the latent image on the latent image carrier with the developer according to (1), wherein a first gap between the first regulating member and the developer carrier; A second gap between the developer carrier and the product of the first gap and the second gap are each a predetermined range, and a gap between the developer carrier and the latent image carrier is a predetermined range; In addition, an image forming apparatus using a developer in which the fluidity of the developer is within a predetermined range. 4. The image forming apparatus according to claim 3, wherein the first gap between the first regulating member and the developer carrier is G.
d, when the second gap between the second regulating member and the developer carrier is PreGd, and the product of the first gap and the second gap is Gd * PreGd, Gd = 0.25 to Gd = 0.25.
0.45 mm, PreGd = 0.7-1.3 mm, G
d * PreGd = 0.2-0.3, and Gp = 0.3-0.4 mm, where Gp is the gap between the developer carrier and the latent image carrier; and The developer is JIS Z2502 (metal powder flowability measurement method)
Out of the developer (time from the start to the end of the flow when the developer having a toner concentration of 10 wt% is set in a funnel having a hole diameter of 5 mm and the developer is dropped by its own weight) is 10 seconds. An image forming apparatus, wherein the time is at least 30 seconds.