JP3444238B2 - 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 for developing an electrostatic latent image in an electronic copying device such as a printer.

[0002]

2. Description of the Related Art Conventionally, a developing device using a one-component developer has a developing device (hereinafter referred to as "toner") concentration detecting device and a controlling device as compared with a developing device using a two-component developer. Since it is unnecessary and no carrier adheres to the latent image carrier during development, even if the latent image carrier is cleaned with a blade after visible image transfer, the latent image carrier surface is not damaged and cleaning is easy. What you can do
There are advantages such as simplification and downsizing of the device.

However, the developing device using the one-component developer has such advantages, but on the other hand, since there is no magnetic attraction like the carrier, the uncharged toner (developer) is the end of the developing roller. There is a problem of leaking from the department.

At present, in a developing device using a one-component developer, it is common practice to use an elastic foaming agent such as urethane foam as a means for sealing the toner. Further, when the elastic foaming agent is used, there is an advantage that it is easy to fill the gap between the developing roller, the casing, and the layer thickness regulating means because of the large elasticity.

[0005]

However, when an elastic foaming agent is used as the sealing means, it is difficult to seal an acute gap, and in particular, the developer layer thickness regulating means which is the R portion of the developing roller and the blade. It is not possible to fill the wedge-shaped gap formed with the R part of the. Further, since the sealing means is attached to the casing, it is difficult to determine the positions of the sealing means and the layer thickness regulating means. Furthermore, when the sealing means is attached, the sealing means is stretched and cannot be attached to the proper position.

For this reason, there is still a problem that toner leakage occurs. Further, since a sealing material such as a sponge is attached to the inside of the casing, there is a problem that workability is poor.

Therefore, it is an object of the present invention to provide a developing device in which a blade is used as the developer layer thickness regulating means and which can prevent the developer from leaking.

[0008]

In order to solve this problem, the developing device of the present invention provides a developer to the electrostatic latent image formed on the photoconductor to visualize the electrostatic latent image. And a casing for storing the developer, in which the developing roller is rotatably attached, and a developing roller which is attached to the casing such that the developing roller can be pressed into contact with the developing roller and is supplied to the developing roller. Layer thickness control means for controlling,
A layer formed by being incorporated into both ends of the casing and the layer thickness regulating means so as to cover at least a part of a peripheral surface of both ends of the developing roller in the longitudinal direction, and a layer formed by the layer thickness regulating means.
Make sure there is no part in contact with the casing within the thickness regulation range
And a developer sealing means having a gap formed therein .

This makes it possible to fill the gap generated between the developer layer thickness regulating means and the developing roller.
It is possible to prevent the developer from leaking in the developing device in which the blade is used as the developer layer thickness regulating means.

Further, since it is not necessary to attach the developer sealing means, it is possible to improve workability and reduce the number of work steps.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is
A developing roller that supplies a developer to the electrostatic latent image formed on the photoconductor to visualize the electrostatic latent image; a casing to which the developing roller is rotatably attached to store the developer; A layer thickness regulating means, which is attached to the casing so as to be capable of pressing contact with the developing roller and regulates the layer thickness of the developer supplied to the developing roller, and at least a part of the circumferential surface of both ends of the developing roller in the longitudinal direction. The casing and the layer thickness regulating means are incorporated into both ends of the casing, and the casing is formed within the layer thickness regulating range of the layer thickness regulating means.
A developer sealing means having a gap formed so that there is no portion in contact with the sing , and the layer thickness regulating means may be influenced by the casing via the developer sealing means. Since it is eliminated, there is an effect that a uniform layer thickness can be stably formed.

According to a second aspect of the present invention, the developer sealing means is integrated with both end portions of the layer thickness regulating means so as to cover at least a part of the peripheral surface of both end portions in the longitudinal direction of the developing roller. The developing device according to claim 1, wherein the blade is used as the layer thickness regulating means because the gap can be filled between the layer thickness regulating means and the developing roller. It has an effect that it is possible to prevent the developer from leaking in the developing device. Further, since it is not necessary to attach the developer sealing means, there is an effect that the workability can be improved and the work man-hour can be reduced.

The invention according to claim 3 of the present invention is a developer.
The sealing means and the casing are fixed by concave and convex fitting
The developing device according to claim 1 , wherein the developer sealing means can be easily assembled into or reassembled from the casing, and the developer can be prevented from leaking at a joint portion between them. Has the effect of becoming.

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

FIG. 1 shows an embodiment of the present invention.
Starting from FIG. In these drawings, the same members are designated by the same reference numerals, and duplicate explanations are omitted.

FIG. 1 is an explanatory view showing an image forming apparatus equipped with a developing device according to an embodiment of the present invention.
1 is a sectional view showing a process unit including a developing device attached to the image forming apparatus in FIG. 1, FIG. 3 is an enlarged sectional view showing a main part of FIG. 2, and FIG. 4 is attached to the image forming apparatus in FIG. FIG. 5 is a perspective view showing another example of the toner sealing means and blade attached to the image forming apparatus of FIG. 1, and FIG. 6 is a perspective view showing the image forming apparatus of FIG. FIG. 7 is a perspective view showing still another example of the attached toner sealing means and blade, FIG. 7 is an enlarged perspective view of a main part of FIG. 6, and FIG. 8 is a plan view of FIG.

As shown in FIG. 1, the image forming apparatus of this embodiment has four image forming stations 1a, 1b,
1c and 1d are arranged. Each of the image forming stations 1a, 1b, 1c, 1d has a photoconductor drum (photoconductor) 2a, 2b, 2c, 2d as an image carrier, and around the photoconductor drums 2a, 2b. , 2
Charging means 3a, 3 for uniformly charging the surfaces of c, 2d
b, 3c, 3d, developing means 4a for visualizing the electrostatic latent image,
4b, 4c, 4d, cleaning means 5a, 5b, 5c, 5d for removing the residual toner, and exposure means 6a of a scanning optical system for irradiating the respective photosensitive drums 2a, 2b, 2c, 2d with light according to image information. , 6b, 6c, 6d, and transfer means 8a, 8b, 8c, 8d for transferring the toner image to the intermediate transfer belt (transfer material) 12 constituting the transfer means 7, respectively.

Here, the image forming stations 1a, 1
In b, 1c, and 1d, a yellow image, a magenta image, a cyan image, and a black image are formed, respectively, and the exposure unit 6
From a, 6b, 6c, and 6d, exposure light 9 corresponding to a yellow image, a magenta image, a cyan image, and a black image
a, 9b, 9c and 9d are output.

Each image forming station 1a, 1b, 1
c, 1d, the photosensitive drums 2a, 2b,
An endless belt-shaped intermediate transfer belt 12 supported by rollers 10 and 11 is disposed below the rollers 2c and 2d, and rotates in the direction of arrow A.

Further, the sheet material 17 stored in the paper feed cassette 16 is fed by the paper feed roller 18, passed through the sheet material transfer roller 19 and the fixing means 20, and ejected to a paper ejection tray (not shown). It

In the color image forming apparatus having the above-mentioned structure, first, in the image forming station 1d, image information is formed on the photosensitive drum 2d by the known electrophotographic process means using the charging means 3d and the exposing means 6d. A latent image of black component color is formed. After that, the developing means 4
At d, a developer having black toner is visualized as a black toner image, and the black toner image is transferred to the intermediate transfer belt 12 by the transfer unit 8d.

On the other hand, while the black toner image is being transferred to the intermediate transfer belt 12, the image forming station 1c
The latent image of the cyan component color is formed by the developing means 4c, the cyan toner image is visualized by the cyan toner by the developing means 4c, and this is transferred by the transferring means 8c, and the black toner previously transferred onto the intermediate transfer belt 12. Superimposed on the image.

Thereafter, image formation is similarly performed on the magenta toner image and the yellow toner image, and when the four color toner images are superposed on the intermediate transfer belt 12, the paper feed roller 18 feeds the paper feed cassette 16 On the sheet material 17 such as paper taken out from the sheet material transfer roller 19
Thus, the toner images of four colors are collectively transferred and conveyed, and are fixed by heating by the fixing unit 20 to obtain a full-color image on the sheet material 17.

The photosensitive drums 2a, 2b, 2c and 2d, which have been transferred, have cleaning means 5a,
The residual toner is removed at 5b, 5c and 5d, and the printing operation is completed in preparation for the next image formation to be performed subsequently.

As shown in FIGS. 2 and 3, in the casing 30 of the process unit attached to such an image forming apparatus, the photosensitive drum 3 on which an electrostatic latent image is formed is formed.
1. Charging means 33 for uniformly charging the surface of the photosensitive drum 31, a developing roller 21 for supplying toner to the photosensitive drum 31 to visualize an electrostatic latent image, and a rotation axis of the developing roller 21. A toner supply roller (supply roller) which is provided in pressure contact with each other in parallel, and which supplies the toner taken out from the toner cartridge 34 and a blade 22 for thinning the toner adhering to the developing roller 21 and agitated by the agitator 35 to the developing roller 21. ) 23 is rotatably mounted.

The casing 30 has a cleaning means 32 for cleaning the outer peripheral surface of the photosensitive drum 31.
Is attached.

Then, the developing roller 21 and the toner supply roller 23 rotate in the same direction, and the photosensitive drum 31
Rotates in the opposite direction.

The developing roller 21 and the toner supply roller 23 are arranged between the shafts of the developing roller 21 and the toner supply roller 23.
It is smaller than the sum of the radius of and. The pressure contact amount here is about 0.3 to 1.5 mm.

The developing roller 21 is formed by integrally molding an elastic body such as silicon rubber or polyurethane rubber, which is made conductive by adding carbon on the outer circumference of a metal shaft, to a thickness of about 0.5 to 4 mm. Volume resistance value is 10
It is designed to be about ² Ωcm to 10 ⁷ Ωcm. The toner supply roller 23 is formed by integrally molding urethane foam or the like on the outer circumference of the metal shaft.

Non-magnetic one-component toner is stored in the toner cartridge 34, and this toner is stored in the casing 30.
It is dropped inside. Then, the toner is agitated by the agitator 35 to prevent toner blocking and to convey the toner to the toner supply roller 23.

The toner supply roller 23 is the developing roller 21.
The toner rotates on the developing roller 21 with a relative speed difference so that the toner adheres to the developing roller 21 at the contact portion with and the residual toner on the developing roller 21 after the development is scraped off. The scraped toner is mixed with unused toner in the casing 30 and reused.

The blade 22 is a toner layer thickness regulating member (developer layer thickness regulating means) having an elastic rubber member, and has a free end, and the other end is fixed to plate-like elastic supporting members 24 and 25.

The blade 22 is made of a metal such as a phosphor bronze plate and a stainless spring material, and the rubber member 22a attached to the free end is processed to have an arc-shaped cross section and pressed against the peripheral surface of the developing roller 21 at the arc-shaped portion. is doing.

In order to charge the toner for the rubber member 22a, a material separated from the toner in the order of frictional electrification is selected. For example, silicone rubber, Teflon (registered trademark) rubber, polyimide rubber, polyester rubber, urethane rubber, etc. The main component is the resin material.

By the toner supply roller 23, the developing roller 2
The toner supplied to No. 1 is regulated in layer thickness on the developing roller 21 by the blade 22 and is charged to the same polarity as the electrostatic latent image. Then, the charged toner comes into contact with the rotating photosensitive drum 31, and the writing device (not shown) causes the photosensitive drum 31 to be driven by the bias potential applied to the developing roller 21 by the bias voltage applying device (not shown). Development is performed by being attracted by the charges of the electrostatic latent image formed above. It should be noted that the residual toner after the development is completed is again stored in the casing 30 and mixed with new toner as described above.

Here, the contact pressure between the blade 22 and the developing roller 21 becomes too large when the required rotational load torque of the developing roller 21 exceeds 3.5 kgfcm, and therefore becomes 1
It should be 0 gf / mm or less. Also, the blade 2
The radius of the arc-shaped portion at the free end of 2 is set to 0.5 to 1.5 mm in order to obtain the required toner layer thickness and the required charge amount.

To the developing roller 21, the toner supply roller 23 is provided on the downstream side of the developing area of the photosensitive drum 31 in the rotation direction.
A sheet material 36 is arranged on the upstream side in the rotational direction of the pressure contact position with the developing roller 21 so as to uniformly abut in the longitudinal direction of the developing roller 21 to prevent toner leakage. This sheet material 36
Is formed of, for example, urethane rubber or PET film.

The developing roller 21 has a blade 22.
Toner seal means (developer seal means) 37 for preventing toner from leaking are provided at both ends of the position where is pressed and contacted.

The toner sealing means 37 is the developing roller 21.
The frictional resistance increases because it comes into contact with the rubber part. Therefore, nitrile rubber, acrylic rubber, silicone rubber,
It is made of an elastic material such as a rubber material or a resin material having good slidability and wear resistance such as fluororubber or tetrafluororesin. Then, as shown in FIG. 4, by integrally molding with the blade 22, it is integrally attached to both ends of the blade 22 in the longitudinal direction. Therefore, the blade 22 and the toner sealing means 37 are unitized.

As a result, the positioning for filling the gap between the blade 22 and the developing roller 21 in the toner sealing means 37 can be surely performed, as compared with the conventional case where a sponge material or the like is attached to the casing with double-sided tape or the like. Done. Therefore, a gap generated between the blade 22 and the developing roller 21 due to a sticking error, a casing size error, or the like can be filled, and toner leakage can be prevented.

Further, it becomes unnecessary to attach the toner sealing means 37 to a portion which is difficult to work inside the casing 30, so that it is possible to improve workability and reduce the number of work steps.

Here, when an external force is applied to the blade 22 which is pressed against the developing roller 21 and thins the toner on the developing roller 21, a prescribed layer thickness cannot be obtained or a uniform layer thickness is obtained. However, there is a problem in that it cannot be formed.

Therefore, as shown in FIG. 5, a gap of a predetermined amount (for example, 0.5 mm or more) is provided in the toner sealing means 37 so that there is no portion in contact with the casing 30 within the layer thickness regulation range of the blade 22. 37d is formed. As a result, the blade 22 moves the toner seal means 37.
Since it is not affected by the casing 30 through the, the uniform layer thickness can be stably formed.

Here, as described above, conventionally, when the toner sealing means 37 was incorporated into the casing 30, it was fixed with a double-sided tape or the like. Then, when the toner sealing means 37 is fixed to the casing 30 using the double-sided tape,
Even if a pasting error or a defect occurs, there is a problem that the pasting cannot be performed again.

Therefore, in the present embodiment, as shown in FIG. 5, the width of, for example, 0.5 to 3.0 m is set in the entire circumferential direction of the portion of the toner sealing means 37 that contacts the casing 30.
The convex portion 37b having a height of about m and a height of about 0.3 to 1.0 mm
Is formed, and a concave portion (not shown) is further formed in a portion facing the convex portion 37b so that they can be press-fitted to each other for attachment. The irregularities may be reversed.

This eliminates the need for fixing with a double-sided tape or an adhesive, which facilitates assembly and reassembly. Further, since both are press-fitted, it is possible to prevent the toner from leaking even in this portion.

Further, as shown in FIG. 5, the toner sealing means 37 is carried away by the rotation of the developing roller 21 on the side of the casing 30 at the opposite end to which the blade 22 of the toner sealing means 37 is attached. In order to prevent this, a rotation preventing convex portion 37c that also serves as positioning is formed. Further, a detent recess (not shown) is formed in a portion of the casing 30 facing the protrusion 37c, and both are press-fitted.

Here, nitrile rubber, acrylic rubber, silicon rubber, fluororubber, tetrafluororesin or the like is used for the toner sealing means 37, and the friction coefficient of the portion in contact with the developing roller 21 is 0. It is set to 1 to 0.8. If the friction coefficient is too low, the developer easily enters and toner leakage occurs, and if it is too high, problems such as an increase in load torque of the developing device and an increase in heat due to friction occur. Then, in order to reduce such a coefficient of friction, a portion of the toner sealing means 37 that comes into contact with the developing roller 21 is subjected to Niftron coating.

Next, as shown in FIGS. 6 to 8, the toner sealing means 37 is provided with a convex rib portion 37e inclined inward with respect to the developing roller shaft on the inner peripheral side, and the developing roller 21 is formed at the edge thereof. It can be configured to contact.

As a result, the contact area between the toner sealing means 37 and the developing roller 21 can be minimized, and the load torque and friction heat can be prevented from increasing.

In this embodiment, the convex rib portion 37e has a height of about 0.5 to 2.0 mm and a width of 0.5.
Is 1.5 mm, and the inclination angle of the convex rib portion 37e is 30 to 60 degrees. In addition, the amount of biting of the convex rib portion 37e into the developing roller 21 is 0.1 to 0.8 mm.

The convex rib portion 37e provided on the toner sealing means 37 is provided inside the toner sealing means 37 with an inclination so that the toner is pushed back into the casing 30 with respect to the rotation of the developing roller 21. ing.

When the toner accumulates on the back of the convex rib portion 37e, the toner is constantly heated by frictional heat, so that the toner is melted and fixed. Therefore, if the convex rib 37e is formed in the toner sealing means 37 so that the toner is pushed back to the inside of the casing 30 with respect to the rotation of the developing roller 21, there will be nothing on the back surface. Therefore, the toner is not accumulated in this portion, the thermal damage to the toner is eliminated, and the problem of toner sticking can be solved.

Here, the convex rib portion 37e of the blade 22 and the toner sealing means 37 which come into contact with the developing roller 21.
If the blade 22 is higher than the toner sealing means 37 with respect to the developing roller 21, the toner sealing means 3
A gap is formed between the convex rib portion 37e of No. 7 and the developing roller 21 to cause toner leakage. On the contrary, the toner sealing means 3
When the convex rib portion 37e of No. 7 is higher than the blade 22, there is a gap between the blade 22 and the developing roller 21 and toner leakage occurs.

Therefore, in this embodiment, the blade 22 and the convex rib portion 37e of the toner sealing means 37 are arranged on the same circumference with respect to the developing roller 21 in the assembled state. . As a result, the gap between the developing roller 21, the blade 22, and the toner sealing means 37 can be filled, and toner leakage can be prevented.

Further, when the toner enters outside the layer thickness regulation range of the blade 22, the toner may be separated from the developing roller 21 and scattered to the outside of the casing 30 because it is not charged.

Therefore, with respect to the rotation of the developing roller 21, the convex rib portion 37e of the toner sealing means 37 is located outside the layer thickness regulation range of the blade 22 on the upstream side and within the layer thickness regulation range of the blade 22 on the downstream side. It is configured to be located inside.
This makes it possible to return the toner outside the layer thickness regulation range of the blade 22 into the casing 30.

In the present embodiment, the material of the sheet material 36 is urethane rubber, PET film or the like,
Its thickness is 0.05 to 1.0 mm. The sheet material 36 is attached to the casing 30 with a double-sided tape or the like, and the tip end of the sheet material 36 is in contact with the surface longitudinal direction of the developing roller 21. The convex rib portion 37e of the toner sealing means 37 is 0.1 to 1.0 even for the sheet material 36.
The sheet material 36 and the convex rib portion 37e of the toner sealing means 37 are formed so as to have a region intersecting the circumferential direction of the developing roller 21.

As a result, the toner sealing means 37 is prevented from being taken off by the developing roller 21 and the toner cannot be sealed. Further, it becomes possible to surely fill the gap between the sheet material 36 and the toner sealing means 37 without using any other member.

[0065]

As described above, according to the present invention, since the gap generated between the developer layer thickness regulating means and the developing roller can be filled, the blade is used as the developer layer thickness regulating means. It is possible to obtain an effective effect that it is possible to prevent the developer from leaking in the developing device.

Further, according to the present invention, since it is not necessary to attach the developer sealing means, it is possible to obtain an effective effect that the workability can be improved and the work man-hour can be reduced.

If a gap is formed between the developer sealing means and the casing within the layer thickness regulation range by the developer layer thickness regulating means, the developer layer thickness regulating means will affect the casing through the developer sealing means. Since it is not received, an effective effect that a uniform layer thickness can be stably formed can be obtained.

If the developer sealing means and the casing are fixed by the concave and convex fitting, the developer sealing means can be easily assembled and reassembled in the casing, and the developer can be prevented from leaking at the joint portion thereof. The effective effect of becoming is obtained.

If the friction coefficient of the portion of the developer sealing means that contacts the developing roller is adjusted to a predetermined value, the developer may enter between the developer sealing means and the developing roller and the load torque of the apparatus may increase. It is possible to obtain an effective effect that it becomes possible to prevent such a trouble as to occur.

When the convex rib portion is formed, the developer sealing means comes into contact with the developing roller at the edge of the convex rib portion.
The contact area between the two is minimized, and an effective effect that the increase in load torque and the increase in friction heat can be prevented can be obtained.

If the convex rib portion is formed so as to be inclined inside the casing so that the developer is pushed back, and is formed inside the developer sealing means, the same developer continues to stay around the developer sealing means. An effective effect of being able to prevent sticking due to frictional heat is obtained.

If the developer layer thickness regulating means and the convex rib portion are formed on the same circumference with respect to the developing roller, a gap may be formed between the developer sealing means and the developing roller, or the developer layer thickness may be increased. An effective effect is obtained in that a gap is prevented from being formed between the regulating means and the developing roller.

With respect to the rotation of the developing roller, the convex rib portion is outside the layer thickness regulating range of the developer layer thickness regulating means on the upstream side and is within the layer thickness regulating range of the developer layer thickness regulating means on the downstream side. If formed inside, it is effective that the developer leaking from the end of the developer layer thickness regulating means can be returned into the casing through the gap between the developer sealing means and the developer layer thickness regulating means. The effect is obtained.

By arranging the tip of the sheet material so as to be in contact with the longitudinal direction of the surface of the developing roller and forming a region in the sheet material and the convex rib portion which also intersects with the circumferential direction of the developing roller, the developer seal is formed. It is possible to prevent the means from being taken away by the friction of the developing roller to make it impossible to seal, and it is possible to surely fill the gap between the sheet material and the developer sealing means, which is an effective effect.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an image forming apparatus to which a developing device according to an embodiment of the present invention is attached.

2 is a sectional view showing a process unit including a developing device attached to the image forming apparatus of FIG.

FIG. 3 is a cross-sectional view showing an enlarged main part of FIG.

FIG. 4 is a perspective view showing an example of a toner sealing unit and a blade attached to the image forming apparatus of FIG.

5 is a perspective view showing another example of the toner sealing means and the blade attached to the image forming apparatus of FIG.

6 is a perspective view showing still another example of the toner sealing means and the blade attached to the image forming apparatus of FIG.

FIG. 7 is an enlarged perspective view showing a main part of FIG.

FIG. 8 is a plan view of FIG.

[Explanation of symbols]

21 developing roller 22 Blade (developer layer thickness regulating means) 23 Toner supply roller (supply roller) 30 casing 31 photoconductor drum (photoconductor) 36 sheet materials 37 toner seal means (developer seal means) 37e Convex rib part

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshimi Hattori 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Yoshihiro Mizoguchi, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Yoshiaki Ijima 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor, Yuzo Kawano 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (56) References JP-A-4-345181 (JP, A) JP-A-9-325603 (JP, A) JP-A-8-179625 (JP, A) JP-A-4-243277 (JP, A) JP-A-9-101677 (JP, A) Japanese Patent Laid-Open No. 8-146761 (JP, A) Actual Development 6-16963 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 15/08 505 G03G 15 / 08 504

Claims (3)

(57) [Claims] 1. A developing roller for supplying a developer to an electrostatic latent image formed on a photoconductor to visualize the electrostatic latent image; and a developing roller rotatably attached to store the developer. A casing for controlling the layer thickness of the developer supplied to the developing roller, the casing being attached to the casing so as to be in pressure contact with the developing roller, and the peripheral surface of the developing roller in the longitudinal direction. A layer formed by being incorporated into both ends of the casing and the layer thickness regulating means so as to cover at least a part, and formed by the layer thickness regulating means.
Make sure there is no part in contact with the casing within the thickness regulation range
And a developer sealing means having a gap formed therein . 2. The developer sealing means is provided for the developing device.
2. The developing device according to claim 1, wherein the developing device is integrally formed on both end portions of the layer thickness regulating means so as to cover at least a part of the peripheral surfaces of both end portions in the roller longitudinal direction. 3. The developing device according to claim 1, wherein the developer sealing means and the casing are fixed by concave and convex fitting.