JP3224638B2 - Developing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device used in an image forming apparatus such as a copying machine, a facsimile, a printer, etc., and more particularly, to a developer carrying member and a developer supplying device. A developer supply unit, and at least one developer conveying member that feeds the developer in a direction of the developer supply unit; and an axial end of the developer supply unit and the developer supply unit. The present invention relates to a developing device having a gap between a supporting side plate.

[0002]

2. Description of the Related Art Conventionally, for example, in a developing device in which a developer carrying member and a developer supply means constituted by an elastic member such as a sponge material are pressed against each other and rotated, the developer supply means is provided with a developing means. When the developer is pressed against the developer carrier, the air inside the developer supply means is discharged, and the discharged air may scatter the developer on the air flow path to the outside of the developing device. Therefore, in order to reduce the scattering of the developer due to the air flow in the developing device as described above, measures such as providing a shielding plate or a fence in the developing device have been taken. Further, a gap is provided between an axial end portion of the developer supply unit and a developing device side plate that supports the developer supply unit,
Measures are taken to release the flow of air generated by pressing the developer supply means against the developer carrier in the lateral direction of the developing device.

[0003] Further, the present applicant has heretofore attempted to prevent the developer from overflowing or blowing out of the developing device.
A developing device provided with a developer shielding member whose front end is located at a region facing the developer carrying member and the developer supply means or at the upstream side in the rotation direction of the developer carrying member, a part of which is in contact with the developer carrying member; (See, for example, JP-A-61-165779). In order to prevent the developer from leaking at both ends below the opening provided with the developer carrying member of the developing device, the width of the opening in the axial direction of the developer carrying member is set in the same direction as the developer supply means. There is also known an intermediate wall in which a developer outflow regulating window narrower than the length of the developer is provided inside the developing device so as to regulate the amount of the developer flowing out to the developer supply means side ( For example, see JP-A-3-84573.

[0004] Incidentally, the scattering of the developer to the outside of the developing device may be caused by an insufficient charge amount of the developer. If the developer with insufficient charge scatters outside the developing device, it may cause an abnormal image. In order to prevent image quality deterioration due to insufficient charge amount of the developer, the present applicant has conventionally used a developer supply means for supplying developer newly supplied to the receiving portion of the hopper of the developing device. A developing device provided with a partition member for preventing the developer from being supplied to a position on the upstream side in the rotation direction of the developer carrying member from a position where the end portion of the developer layer thickness regulating member on the developer carrying member abuts on the developer carrying member in a short-circuited manner (See, for example, JP-A-61-156167).

[0005]

However, the above-mentioned conventional structure in which a shielding plate and a fence are provided, and a gap between an axial end of the developer supply means and a side plate of the developing device supporting the developer supply means are provided. The configuration in which the flow of the air generated by the pressure contact of the developer supply unit with the developer carrier is released in the lateral direction of the developing device is considered when viewed over time or when applied to a developing device corresponding to a high-speed machine. There was a problem that it was insufficient. That is, the shielding plate and the fence deteriorate with time, and the effect cannot be sufficiently exhibited. In the case where the flow of air is released in the lateral direction of the developing device, if a sufficient air flow path is not secured between the side plate of the developing device and various members in the developing device, the developer supply means and the developer conveying member are not provided. When such a member rotates at a high speed, the developer is scattered.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a developing method capable of preventing scattering of a developer even when viewed over time or when applied to a high-speed machine. It is to provide a device.

Further, the scattering of the developer is caused not only by the air discharged from the inside of the developer supply means when the developer supply means is pressed against the developer carrier as described above, but also by the developer conveying member. It may also be caused by the pressure of the developer fed in the direction.

Accordingly, another object of the present invention is to provide a developing device which can prevent the developer from being scattered by the flow of air generated by the pressure of the developer fed toward the developer supply means by the developer conveying member. That is.

[0009]

To achieve the above Symbol purpose SUMMARY OF THE INVENTION, The invention according to claim 1, a developer bearing member, a developer supply means for supplying the developer to the developer carrying member, said At least one developer conveying member for feeding the developer in the direction of the developer supply means, and between an axial end of the developer supply means and a side plate supporting the developer supply means. In the developing device having a gap, the width of the developer conveying member in the axial direction is equal to or smaller than the width of the developer supply unit in the axial direction, and the gap between the axial end of the developer supply unit and the side plate is set. , the developer accumulated in the gap provided a developer raking member scraped from the gap, just before the developer conveying member feeds the developer in the direction of the developer supply means, said developer scraping member above A developer scraping member for scraping the developer accumulated in the gap; Arranged, it is characterized in that the shaft rotation speed of the developer carrying member and the developer supplying means each have the same. The invention according to claim 2 includes a developer carrying member,
A developer supply unit for supplying a developer to the developer carrier;
At least feeding the developer in the direction of the developer supply means
One developer transport member, and the developer supply
Between the axial end of the step and the side plate supporting the developer supply means.
A developing device having a gap between the developer conveying members;
The width in the axial direction of the developer supply means and less than the width in the axial direction
And the gap between the axial end of the developer supply means and the side plate.
In the gap, the developer accumulated in the gap is scraped out from the gap.
Provided an image agent scraping member, the respective developer scraping member and the developer carrying member is constituted by a member having a plurality of blade members mounted on a rotary shaft, nk1 the blade number of members scraping developer, the rotational speed rk1, the number of blades of the developer conveying member is nA, and the number of revolutions is rA, nk1 × rk1 ≧ n
The number of blades and the number of revolutions of each of the developer scraping member and the developer conveying member are set so as to satisfy the condition of A × rA. The invention according to claim 3 is a development method.
Developer carrier and developer for supplying developer to the developer carrier
Supply means, and the developer is fed in a direction of the developer supply means.
And at least one developer conveying member that fits in
An axial end of the developer supply means and the developer supply means are supported.
A developing device having a gap between the side plate and
The width of the developer conveying member in the axial direction is set in the axial direction of the developer supply unit.
The width of the developer supply means and the end in the axial direction of the developer supply means.
The developer accumulated in the gap is filled in the gap between the
A developer scraping member for scraping off the developer;
Between the axial end of the developer and the side plate supporting the developer conveying member.
A gap is provided between the gaps and the developer is scraped out of the gap.
A second developer scraping member provided, the developer scraping member provided in the gap between the axial end of the developer supply means and the side plate, and an axial end of the developer conveying member; Each of the second developer scraping members provided in the gap between the first developer scraping member and the side plate is constituted by a member having a plurality of blade members attached to a rotating shaft, and the number of blades of the first developer scraping member is Is nk1, the number of rotations is rk1, the number of blades of the second developer scraping member is nk2, and the number of rotations is rk2. The first and second kn1 × rk1 ≧ nk2 × rk2 are satisfied so as to satisfy the following conditions. The number of blades and the number of revolutions of each developer scraping member are set. According to a fourth aspect of the present invention, there is provided a developer carrying member, and the developer carrying member.
Developer supply means for supplying a developer to the body, and the developer supply
At least one developer feeding the developer in the direction of the means
And an axial direction of the developer supply means.
A gap is provided between the end and the side plate supporting the developer supply means.
A developing device having the developer conveying member in the axial direction.
The width of the developer supply means is not more than the width in the axial direction of the developer supply means,
The gap is provided between the axial end of the supply means and the side plate.
Scavenging the developer accumulated between the gaps
A member, and an axial end of the developer conveying member and the developer.
A gap is provided between the side plate supporting the transport member and the gap.
A second developer scraping member for scraping the developer from the gap
The provided, immediately before the developer conveying member feeds the developer in the direction of the developer supply means, said second developer scraped axial end of the member is the developer carrying member and the developer carrying member The second developer scraping member is provided so as to scrape the developer in the gap provided between the second developer scraping member and the side plate supporting the second developer.

[0010]

According to the first to fourth aspects of the present invention, the width of the developer in the developing device in the axial direction of the developer conveying member is equal to or less than the axial width of the developer supply means. Thereby, it is difficult to be fed into the gap between the axial end of the developer supply means and the side plate supporting the developer supply means,
In addition, even if the developer accumulates in the gap, the developer is actively scraped by the developer scraping member, so that a large amount of the developer can be prevented from accumulating in the gap. Also,
As described above, since the width of the developer conveying member in the axial direction is equal to or smaller than the width of the developer supplying unit in the axial direction, the developer is generated by the pressure of the developer conveyed by the developer conveying member. It is possible to prevent the flow of the generated air from acting on the gap as much as possible. In particular, according to the first aspect of the present invention, since the developer accumulated in the gap is always scraped out of the gap by the developer scraping member immediately before the developer conveying member feeds the developer in the direction of the developer supply means,
When the developer is newly fed in the direction of the developer supply means by the developer conveying member, the gap is in a state where the developer hardly accumulates. Therefore, even if the developer is newly fed in the direction of the developer supply means, a large amount of the developer does not accumulate in the gap. According to the second aspect of the present invention, since the developer scraping ability of the developer scraping member is equal to or superior to the developer transport ability of the developer transport member, a large amount of the developer is accumulated in the gap. Can be prevented. According to the third and fourth aspects of the present invention, the developer accumulated in the gap between the axial end of the developer transport member and the side plate supporting the developer transport member is the second developer.
Is scraped out of the gap by the developer scraping member.
Here, in the developing device, the flow of air generated by the pressure of the developer conveyed by the developer conveying member and the developer supply means and the developer carrier formed of an elastic member such as a sponge material are used. The air flow discharged from the developer supply means when rotating by pressing is passed through the gap between the developer supply means and the side plate, and then the axial end of the developer transport member and the side plate However, since the developer is scraped out and the air flow path is secured in the gap between the axial end of the developer conveying member and the side plate, the developer supply means and the developer Even when the conveying member rotates at a high speed, the air flows smoothly through the gap. Further, in the invention of claim 3, the second developer raking member scraping ability of the developer by the first developer raking member provided on the current image agent supply means side is provided on the developer carrying member side The developer supply capacity is equal to or better than that of the developer supply means, so that a large amount of developer can be prevented from accumulating in the gap between the axial end of the developer supply means and the side plate supporting the developer supply means. . In the invention of claim 4, the gap of the developer is provided between the side plates for supporting the axial end portion and the developer conveying member of the current image-transporting member is always developer conveying member developing Immediately before the developer is fed in the direction of the developer supply means, the developer is forcibly scraped out of the gap by the second developer scraping member, so that the air flow path in the developing device can be secured.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a developing device of an electrophotographic copying machine (hereinafter referred to as a copying machine) as an image forming apparatus will be described. In the copying machine according to the present embodiment, when a print button is turned on, a latent image is formed on an image carrier through a reading system, a discharging system, and a writing system (not shown), and the latent image is formed into a toner image by a developing device. The toner image is transferred to a transfer material conveyed at a timing with the leading end of the latent image at a transfer unit, and one copy is obtained via a fixing / discharge unit. Less than,
The developing device according to the present embodiment will be described. The developing device according to the following description uses a non-magnetic one-component developer (hereinafter, referred to as toner) as a developer. FIG. 1 is a schematic configuration diagram of a developing device according to the present embodiment, and FIG. 2 is an upper cross-sectional view of the developing device. This developing device 1 has a leaf spring 10
1 and a cam 102 rotatably disposed such that the peripheral surface thereof is in contact with the leaf spring 101. When the print button is turned on, the cam 102 rotates and the leaf spring 101 is pressed. The entire apparatus is a photosensitive drum 1 as an image carrier
It is designed to be moved in the 00 direction. The housing of the developing device 1 includes a lower casing 2, an upper left lid 3 and an upper right lid 4 attached to the lower casing 2, and the lower casing 2 is located at a position facing the photosensitive drum 100. An opening 5 is formed with the upper left cover 3. Further, in the developing device 1, the photosensitive drum 10
And a sponge roller 7 disposed in pressure contact with the developing roller 6 to supply the toner T to the developing roller 6.
And a first agitator 8 for transporting the toner T in the direction of the sponge roller 7 and a second agitator 9 for transporting the toner T in the direction of the first agitator 8 are rotatable about front and rear side plates 10 and 11 of the developing device 1. It is supported and provided.
Here, a bias voltage is applied to each of the developing roller 6 and the sponge roller 7 so that a potential difference such that the toner T goes to the developing roller 6 is generated.

For example, in the case of N / P development, a developing bias voltage having the same polarity as the toner T is applied to the developing roller 6. Further, a gap holding roller 13 having a diameter slightly larger than the diameter of the developing roller 6 is attached to both ends of the shaft 61 supported by the front and rear side plates 10 and 11 via the ball bearings 12 of the developing roller 6. When the developing device 1 is pushed toward the photosensitive drum 100 by the rotation of the cam 102, the gap holding rollers 13 are formed on aluminum surfaces formed on both ends in the axial direction of the photosensitive drum 100 (referred to as an Al surface in FIG. 2). )
, The movement of the developing device 1 is stopped, and a predetermined gap is formed between the developing roller 6 and the photosensitive drum 100. Further, on the downstream side in the rotation direction of the developing roller 6 with respect to a region A (hereinafter, referred to as a development region) where the developing roller 6 and the photosensitive drum 100 are opposed to each other, the abutting is performed in a forward direction with respect to the rotation direction of the developing roller 6. An inlet seal 14 is provided. The entrance seal 14 does not scrape off the toner T remaining on the developing roller 6 that has passed through the developing area A, thereby preventing the toner T from blowing out from the inside of the developing device 1.

Further, downstream of the pressure contact portion B between the developing roller 6 and the sponge roller 7 in the rotation direction of the developing roller 6,
A thin layer blade 17 as a developer layer thickness regulating member formed wider than the developing roller 6 is provided. Specifically, the thin-layer blade 17 has a belly surface pressed against the developing roller 6 so that the free end 17a is located on the downstream side in the rotation direction of the developing roller 6 and the fixed end 17b is located on the upstream side. It is arranged in the forward direction. The fixed end portion 17b of the thin layer blade 17 is fixedly attached to a blade holder 16 attached to the upper left cover 3 and the upper right cover 4.

The sponge roller 7 has a shaft 71 supported by the front and rear side plates 10 and 11 via a ball bearing 19 and a G seal 20, and is configured to be rotatable by being pressed against the developing roller 6. The length of the sponge roller 7 in the longitudinal direction is shorter than the developing roller 6 and longer than the image area width of the photosensitive drum 100.
1 are formed with gaps D, respectively. Also, shaft 7
A key-shaped toner scraping member 72 is attached to the gap D at both ends in the longitudinal direction. The toner scraping member 72 scrapes the toner accumulated in the gap D.

The first agitator 8 includes a dry bearing 22.
A plate-like member 82 is attached to a shaft 81 supported by the front and rear side plates 10 and 11 through an agitator member 83 having a length of about 3 mm biting into the lower casing 2 at one edge of the plate-like member 82. Is attached. The length of the agitator member 83 in the longitudinal direction (the direction of the axis 81) is set to be the same as the length of the sponge roller 7 in the longitudinal direction. The agitator member 83 slides along the lower casing 2 as the first agitator 8 rotates, and conveys the toner T toward the sponge roller 7. A key-shaped toner scraping member 84 is attached to both ends in the longitudinal direction of the edge of the plate member 82 to which the agitator member 83 is attached. The toner scraping member 84 circulates the toner T in the vicinity of the front and rear side plates 10 and 11 so that the air discharged from the sponge roller 7 forms gaps E formed between the shielding plate 21 and the front and rear side plates 10 and 11, respectively. To make it flow smoothly.

The second agitator 9 has a dry bearing 23
A plate-like member 92 is attached to a shaft 91 supported by the front and rear side plates 10 and 11 via one end. An agitator member 93 having a length of about 1 mm biting into the lower casing 2 is attached to one edge of the plate-like member 92. Is attached.

In the developing device 1 according to the above configuration,
When the print button is turned on and the cam 102 rotates to move the entire apparatus in the direction of the photosensitive drum 100, and the gap holding roller 13 abuts against the aluminum surface of the photosensitive drum 100 and stops, power from a driving device (not shown) is applied. The power is transmitted to the developing roller 6, and the developing roller 6, the sponge roller 7,
The first agitator 8 and the second agitator 9 are each shown in FIG.
It starts to rotate in the direction of the arrow shown inside. Then, the toner T supplied to the sponge roller 7 by the second agitator 9 and the first agitator 8 is pressed against the developing roller 6 by a pressing portion B.
, And adheres to the developing roller 6 to which a voltage having the same polarity as the toner T is applied, and is conveyed by the rotation of the developing roller 6. The toner T on the developing roller 6 is regulated to a predetermined layer thickness by the thin layer blade 17 at a contact portion C between the developing roller 6 and the thin layer blade 17, and is simultaneously triboelectrically charged and conveyed to the developing area A. In the area A, the latent image on the photosensitive drum 100 flies and is developed.

Here, the flow of air in the developing device 1 will be described. In the developing device 1, an air flow is generated when the sponge roller 7 is compressed by the developing roller 6. That is, as shown in FIG. 3, when the sponge roller 7 is compressed in contact with the developing roller 6 at the pressure contact portion B, the sponge roller 7 simultaneously discharges the toner T and air stored therein. At this time, the toner T is transferred to the developing roller 6, while the exhaled air flows right and left through a gap formed by the sponge roller 7 and the lower casing 2, and flows between the sponge roller 7 and the front and rear side plates 10 and 11. Through the gaps D formed respectively, the back side of the developing device 1 (the arrow a shown in FIGS.
Direction).

In the developing device 1, an air flow is also generated by the pressure of the toner T conveyed from the first agitator 8 to the sponge roller 7. Here, FIG.
As shown in (a), the first agitator 8 and the front and rear side plates 10,
If there is no gap between the sponge roller 11 and the sponge roller 7, air flows back to the first agitator 8 side as indicated by an arrow Ha in the drawing, and in this case, the first agitator Although the air flows well when the sponge roller 8 and the sponge roller 7 are rotating at a low speed, the air does not flow well when the sponge roller 7 and the sponge roller 7 are rotating at a high speed, which may cause the toner T to blow out (scatter) from the opening 5.

However, in the developing device 1 according to the present embodiment, since the gap E is provided between the first agitator 8 and the front and rear side plates 10, 11 as shown in FIG. Even when the agitator 8 and the sponge roller 7 rotate at a high speed, the air flows smoothly back to the gap E as shown by the arrow Hb in the figure. In the developing device 1 according to the present embodiment, the toner scraping member 72 is provided in the gap D that is a flow path of the air flow generated when the sponge roller 7 is compressed by the developing roller 6. Since the toner scraping members 84 are provided in the gap E which is a flow path of the air flow generated by the pressure of the toner T conveyed from the agitator 8 to the sponge roller 7, the respective toner scraping members 72, 84 are provided. By scraping out the toner T accumulated in each of the gaps D and E, an air flow path can be secured, and the air flow can be kept smooth.

Further, in the developing device 1 according to the present embodiment, as described above, the agitator member 83 in the longitudinal direction (the shaft 8
The length of the sponge roller 7 is set to be the same as the length of the sponge roller 7 in the longitudinal direction, so that the toner T is provided between the axial end of the sponge roller 7 and the front and rear side plates 10 and 11, respectively. Since the configuration is such that it is difficult to feed the toner T into the gap D, it is possible to prevent a large amount of toner T from accumulating in the gap D, and the flow of air generated by the pressure of the toner T conveyed by the first agitator 8 is transmitted to the gap D. You can make it work as little as possible.

As described above, according to the configuration of the developing device 1 according to the present embodiment, an air flow path can be secured in the developing device 1, and
A large amount of toner T can be prevented from accumulating in the gap D, and the pressure of the toner T conveyed by the first agitator 8 can be prevented from acting on the gap D as much as possible. It is possible to prevent the developing device 1 from scattering from the opening 5 provided with the roller 6 to the outside.
Further, the toner T in the gap D is scraped out by the toner scraping member 72 and the toner D in the gap D is provided by the air discharged from the sponge roller 7 because the toner T in the gap D has little toner T. Of the developing device 1 from the opening 5 can be prevented.
Further, the first agitator 8 applies the toner T to the sponge roller 7.
The sponge roller 7 and the first agitator 8 are rotated at a high speed just before the toner is ejected in the direction of (1), since the toner scraping member 84 is disposed so that the toner scraping member 84 scrapes the toner T accumulated in the gap E. Sometimes,
The flow path of the air generated by the pressure of the toner T sent in the direction of the sponge roller 7 can be secured by the first agitator 8, so that the toner T scatters from the opening 5 where the developing roller 6 is provided to the outside of the developing device 1. Can be prevented. Further, since a large amount of the toner T can be prevented from being accumulated in the gaps D and E with a simple configuration in which the operation timing of the first agitator 8 and the toner scraping members 72 and 84 is set, the development that can prevent the toner T from scattering can be performed. Apparatus 1
Cost can be reduced.

Next, in order to improve the air flow, the clearance D
Another embodiment for preventing the toner T from accumulating in the toner will be described. As shown in FIG. 5, when the number of blades of the toner scraping member 72 is nk ₁ , the number of rotations is rk ₁ , the number of blades of the first agitator 8 is n _A , and the number of rotations is r _A , nk ₁ × r
If the number of blades and the number of revolutions of each of the toner scraping member 72 and the first agitator 8 are set so as to satisfy the condition of k ₁ ≧ n _A × r _A , the toner T
Is greater than or equal to the ability of the first agitator 8 to transport the toner T, and a large amount of toner T can be prevented from accumulating in the gap D. Also, as shown in FIG.
The number of blades of the toner scraping member 72 is nk ₁ and the number of rotations is r.
k ₁ , when the number of blades of the toner scraping member 84 is nk ₂ and the number of rotations is rk ₂ , the toner scraping member 72 and the toner scraping member 84 are respectively adjusted so as to satisfy a condition of nk ₁ × rk ₁ ≧ nk ₂ × rk _2. If the number of blades and the number of rotations are set, the ability of the toner scraping member 72 to scrape out the toner T becomes equal to or more than the ability of transporting the toner T by the toner scraping member 84, and a large amount of toner T accumulates in the gap D. Can be prevented.

According to the above configuration, the set conditions for preventing a large amount of toner T from accumulating in the gap D include the number of blades and the number of rotations of each of the toner scraping members 72 and 84 and the first agitator 8. Since these setting conditions only need to be set so as to satisfy the above conditions, selection of the setting conditions with a high degree of freedom is possible.

[0025]

According to the first to fourth aspects of the present invention, it is possible to prevent a large amount of developer from being accumulated in the gap between the axial end of the developer supply means and the side plate supporting the developer supply means. ,
Further, the flow of air generated by the pressure of the developer conveyed by the developer conveying member can be prevented from acting on the gap as much as possible, so that the developer in the gap is provided in the opening provided with the developer carrier. There is an effect that it is possible to prevent scattering from the developing unit to the outside of the developing device. Further, the developer supply means is composed of an elastic member such as a sponge material, and the developer supply means and the developer carrier are pressed and rotated, and the air in the developer supply means discharged at the time of the pressure contact is formed in the gap. Even in the case of a configuration in which the developer flows through the gap, the developer in the gap is scraped out by the developer scraping member, and there is almost no developer in the gap. This has the effect of preventing the developer from being scattered outside the developing device from the opening provided with the developer carrier. In particular, according to the first aspect of the present invention, a large amount of developer can be prevented from accumulating in the gap with a simple configuration of setting the operation timing of the developer conveying member and the developer scraping member. There is an effect that the cost of the developing device that can prevent the scattering of the toner can be reduced. Further, according to according to the invention of claim 2, the setting condition for preventing the staying developer in a large amount in the gap there is a developer raking member and the developer carrying member each blade number and rotational speed, these Since the setting conditions may be set so as to satisfy the above conditions, there is an effect that the degree of freedom of each setting condition is high. Further, according to claim 3乃
According to the fourth aspect of the invention, even when the developer supply means and the developer conveying member rotate at a high speed, the flow of air in the developing device is limited by the gap between the axial end of the developer conveying member and the side plate. Flows smoothly, so that even when the developing device according to the present invention is used as a developing device for a high-speed machine, there is an effect that the scattering of the developer can be prevented. Further, according to the third aspect of the present invention, the set conditions for preventing a large amount of developer from accumulating in the gap include the number of blades and the number of rotations of each of the first and second developer scraping members, Since these setting conditions may be set so as to satisfy the above conditions, there is an effect that each setting condition has a high degree of freedom. Further , according to the invention of claim 4 , since the air flow path in the developing device can be secured, there is an effect that the developer can be prevented from scattering from the opening to the outside of the developing device .

[Brief description of the drawings]

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

FIG. 2 is an upper cross-sectional view of the developing device.

FIG. 3 is an explanatory diagram illustrating a flow of air at a pressure contact portion between a developing roller and a sponge roller.

FIG. 4A is an explanatory diagram of an air flow when there is no gap between a first agitator and a side plate. (B) is the first
Explanatory drawing about the flow of air when there is a gap between the agitator and the side plate.

FIG. 5 is an explanatory diagram relating to setting conditions of a first agitator and a sponge roller side toner scraping member.

FIG. 6 is an explanatory diagram regarding setting of conditions for a first agitator-side toner scraping member and a sponge roller-side toner scraping member.

[Explanation of symbols]

 Reference Signs List 6 developing roller 7 sponge roller 8 first agitator 9 second agitator 17 thin layer blade 72 toner scraping member 84 toner scraping member

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuhiro Nishito 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Ichiro Komuro 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (72) Inventor Naoki Iwata 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh (72) Shigeki Sawa 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh Company (72) Inventor Nobuhiro Shima 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. Ricoh Company (56) References JP-A-3-84573 (JP, A) JP-A-2-58768 ( JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 15/08

Claims (4)

(57) [Claims] 1. A developer carrier, developer supply means for supplying a developer to the developer carrier, and at least one developer conveying member for feeding the developer in a direction of the developer supply means. A developing device having a gap between an axial end of the developer supply means and a side plate supporting the developer supply means, wherein the width of the developer transport member in the axial direction is set to the width of the developer. The width of the supply means in the axial direction or less, provided in the gap between the axial end of the developer supply means and the side plate, a developer scraping member for scraping the developer accumulated in the gap from the gap , The developer transport
A member feeds the developer in the direction of the developer supply means.
Immediately before, the developer scraping member accumulated in the gap.
The developer scraping member is disposed so as to scrape the developer.
And the shaft rotation of each of the developer conveying member and the developer supply means.
A developing device having the same number . 2. A developer-carrying member, and a developer on the developer-carrying member.
Supply means for supplying the developer and the direction of the developer supply means
At least one developer transport member for feeding the developer to
And an axial end of the developer supply means and
Development with a gap between the side plate supporting the image agent supply means
In the apparatus, the width of the developer conveying member in the axial direction is set to the axis of the developer supply unit.
The width of the developer supply means and the axial end of the developer supply means.
The developer collected in the gap is filled in the gap between the side plate and the gap.
A developer scraping member for scraping the developer,
And the developer transport member described above on the rotating shaft.
The developer is constituted by a member to which a number of blade members are attached.
The number of blades of the scraping member is nk1, the number of rotations is rk1,
Assuming that the number of blades of the agent conveying member is nA and the number of rotations is rA, the developer satisfies the condition of nk1 × rk1 ≧ nA × rA
The number of blades of the scraping member and the developer conveying member,
A developing device wherein the number of rotations is set . 3. A developer carrier, and a developer on the developer carrier.
Supply means for supplying the developer and the direction of the developer supply means
At least one developer transport member for feeding the developer to
And an axial end of the developer supply means and
Development with a gap between the side plate supporting the image agent supply means
In the apparatus, the width of the developer conveying member in the axial direction is set to the axis of the developer supply unit.
The width of the developer supply means and the axial end of the developer supply means.
The developer collected in the gap is filled in the gap between the side plate and the gap.
A developer scraping member for scraping the developer,
An axial end portion of the member and a side plate supporting the developer conveying member;
And a developer is scraped out of the gap.
A second developer scraping member, and the developer supply means;
Provided in the gap between the axial end and the side plate
The developer scraping member and the axial direction of the developer conveying member
The second end provided in the gap between the facing end and the side plate.
A plurality of blades around each of the developer scraping members
The first developer scratch is formed by a member to which a member is attached.
The number of blades of the extraction member is nk1, the rotation speed is rk1, and the second
The number of blades of the developer scraping member is nk2, and the number of rotations is rk2.
Satisfies the condition of nk1 × rk1 ≧ nk2 × rk2
As described above, each of the first and second developer scraping members
A developing device wherein the number of blades and the number of rotations are set. 4. A developer carrying member, and the developer carrying member is provided with a developer.
Supply means for supplying the developer and the direction of the developer supply means
At least one developer transport member for feeding the developer to
And an axial end of the developer supply means and
Development with a gap between the side plate supporting the image agent supply means
In the apparatus, the width of the developer conveying member in the axial direction is set to the axis of the developer supply unit.
The width of the developer supply means and the axial end of the developer supply means.
The developer collected in the gap is filled in the gap between the side plate and the gap.
A developer scraping member for scraping the developer,
An axial end portion of the member and a side plate supporting the developer conveying member;
And a developer is scraped out of the gap.
A second developer scraping member, and the developer transport member
Directly feeds the developer in the direction of the developer supply means.
Before, the second developer scraping member is connected to the developer transport section.
Between the axial end of the developer and the side plate supporting the developer conveying member.
The second gap is provided so as to scrape the developer in the gap provided therebetween.
(2) A developer scraping member (2) is provided.
Imaging device.