JP3412573B2 - 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 surface of the latent image carrier 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 general 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 especially the R portion of the developing roller and the toner layer thickness of the developing agent are made thicker. R of blade to regulate
It is not possible to fill the wedge-shaped gap formed by the part.

Further, since the sealing means is attached to the casing, it is difficult to determine the positions of the sealing means and the blade.

Furthermore, when the sealing means is attached, the sealing means is stretched and cannot be attached in a proper position.

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

[0009]

In order to solve this problem, a developing device of the present invention supplies a developer to an electrostatic latent image formed on a photoconductor to visualize the electrostatic latent image. a developing roller for the previous SL development with low la is rotatably attached to a casing developer stored, the developing roller the supplied attached to the press-contactable to the casing on the developing roller to the developing Regulate the layer thickness of the agent
Layer thickness regulating means and peripheral surfaces of both ends of the developing roller in the longitudinal direction
Both ends of the layer thickness regulating means so as to cover at least a part of
And a developer sealing means formed on the developer,
The sealing means is provided on the side facing the developing roller.
Line contact with the developing roller inside the image roller width direction
It is configured to have the formed lip portion .

As a result, the developer sealing means has a lip portion.
Since it contacts the developing roller at the edge of the
The contact area between the step and the developing roller can be reduced to the minimum, and the load can be reduced.
It becomes possible to prevent the rise of torque and the rise of friction heat.
Has the action of Also, around the developer sealing means
The developer stays on the surface and is fixed by frictional heat.
Has the effect of being able to prevent

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the invention described in claim 1 of the present invention , a developer is supplied to an electrostatic latent image formed on a photoreceptor.
A developing roller that visualizes the electrostatic latent image, and the developing roller
Is rotatably attached and the developer is stored
The casing and the developing roller can be pressed and contacted with each other.
Installed on the casing and supplied on the developing roller.
Layer thickness regulating means for regulating the layer thickness of the developer, and
At least a part of the peripheral surface of both ends of the developing roller in the longitudinal direction is covered.
Formed on both ends of the layer thickness regulating means as described above.
Sealing means, and the developer sealing means is
Inside of the developing roller width direction on the side facing the developing roller
A lip portion formed in line contact with the developing roller.
A developing device characterized by having
The contact means with the developing roller at the edge of the lip
Minimizes the contact area between the developer seal and the developing roller.
Can be reduced as much as possible and prevent increase of load torque and friction heat.
It has an effect that it becomes possible to do. Also, development
The developer stays around the developer sealing means, which causes friction heat.
The effect of preventing sticking due to
Have.

The invention according to claim 2 of the present invention is a lip
Is the part of the developer sealer that faces the developing roller.
It is formed inside the roller width direction so that it can make line contact with the developing roller.
And the casing against the rotation of the developing roller.
It is installed so that the developer can be pushed back inside.
The developing device according to claim 1, wherein
It is possible to send the developer toward the edge of the housing
Has the effect of becoming.

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

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, and FIG. 2 is shown in FIG.
2 is a sectional view showing a process unit including a developing device attached to the image forming apparatus of FIG. 3, FIG. 3 is an enlarged sectional view showing an essential part of FIG. 2, and FIG. 4 is a blade and blade attached to the image forming apparatus of FIG. FIG. 5 is a perspective view showing an example of the toner seal portion.
1 is a perspective view showing another example of the blade / toner seal portion attached to the image forming apparatus of FIG. 1, FIG. 6 is a front view of the blade / toner seal portion of FIG. 5, and FIG. 7 is the blade / toner seal portion of FIG. FIG. 8 is a perspective view showing still another example of the blade / toner seal portion attached to the image forming apparatus of FIG. 1, and FIG. 9 is attached to the image forming apparatus of FIG. FIG. 10 is a perspective view showing still another example of the blade / toner seal portion, and FIG. 10 is a perspective view showing still another example of the blade / toner seal portion attached to the image forming apparatus of FIG.

As shown in FIG. 1, the image forming apparatus of this embodiment has four image forming stations 1a, 1b, and
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, passes through the sheet material transfer roller 19 and the fixing means 20, and is 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, the magenta toner image and the yellow toner image are similarly formed, 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.

In the casing 30 of the process unit attached to such an image forming apparatus, as shown in FIGS. 2 and 3, the photosensitive drum 3 on which an electrostatic latent image is formed is formed.
1. A charging unit 33 that uniformly charges the surface of the photosensitive drum 31, a developing roller 21 that supplies toner to the photosensitive drum 31 to visualize an electrostatic latent image, and a toner that adheres to the developing roller 21 is thin. A blade / toner seal portion (developer layer thickness regulation / sealing means) 22 for layering and preventing the developer from leaking from the end portion of the developing roller 21, toner taken out from the toner cartridge 34 and agitated by the agitator 35. A toner supply roller (supply roller) 23 for supplying the toner to the developing roller 21 is rotatably attached.

Here, the blade / toner seal portion 22
Is a blade portion (developer layer thickness regulating portion) 22a which is provided in pressure contact with the developing roller 21 in parallel with the rotation axis of the developing roller 21 and thins the toner adhered to the developing roller 21. A toner seal portion (developer seal portion) 22b is integrally formed with the blade portion 22a at both ends of the position where the blade portion 22a comes into pressure contact and is pressed into contact with the peripheral surface of the developing roller 21 to prevent toner leakage. Has been done. Further, the blade portion 22a is processed into an arc shape in cross section and is in pressure contact with the peripheral surface of the developing roller 21.

The blade / toner seal portion 22 uses a plate-shaped metal member such as a phosphor bronze plate and a stainless spring material as a base material, and the blade portion 22a and the toner seal portion 22b are integrally formed by an elastic member such as rubber. .

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 supplying 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 made of an elastic material such as silicon rubber or polyurethane rubber, which is made conductive by adding carbon to the outer circumference of the metal shaft, in an amount of 0.5 to 4.0 m.
The volume resistance value is designed to be about 10 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.

The toner cartridge 34 stores non-magnetic one-component toner, 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 the unused toner in the casing 30 and used again.

In order to charge the toner for the blade portion 22a, a material separated from the toner in the order of frictional electrification is selected. For example, silicone rubber, Teflon rubber, polyimide rubber, polyester rubber, urethane rubber, nitrile rubber, etc. Mainly made of resin material.

The toner supply roller 23 causes the developing roller 2
The toner supplied to No. 1 is regulated in layer thickness on the developing roller 21 by the blade portion 22a 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 13 causes the photosensitive drum 3 to move by the bias potential applied to the developing roller 21 by the bias voltage applying device (not shown).
Development is carried out by being absorbed by the electrification of the electrostatic latent image formed on 1. The residual toner after the development is finished is again absorbed by the casing 30 and mixed with new toner as described above.

Here, the blade portion 22a and the developing roller 2
The contact pressure with 1 must be 10 gf / mm or less because the torque becomes excessive when the required rotational load torque of the developing roller 21 exceeds 3.5 kgf / cm. Further, the radius of the arc-shaped portion at the free end of the blade portion 22a 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, a toner supply roller 23 is provided on the downstream side of the developing area of the photosensitive drum 31 in the rotational 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.

As described above, the developing roller 21 is integrally formed with the toner seal portions 22b at both ends of the position where the blade portion 22a comes into pressure contact with the developing roller 21 to prevent toner leakage. As a result, the positioning for filling the gap between the blade portion 22 and the developing roller 21 in the blade / toner seal portion 22 is surely performed, as compared with the case where a sponge material or the like is attached to the casing with a double-sided tape or the like as in the past. Done. Therefore, a gap generated between the blade portion 22a and the developing roller 21 due to an attachment error, a dimensional error of the casing, or a wedge between the developing roller 21 and the blade portion 22a that cannot be filled with the sponge material. It is possible to fill the gaps in the shape and prevent toner leakage.

Further, since it is not necessary to attach the toner seal portion 22b to a portion that is difficult to work inside the casing 30, it is possible to improve workability and reduce the number of work steps.

Further, since the blade portion 22a and the toner seal portion 22b are integrally formed of the same elastic member, it is possible to reduce the number of parts and the cost of parts.

Here, as shown in FIG. 4, the toner seal portion 22b of the blade / toner seal portion 22 formed integrally with the plate-shaped member is provided on the developing roller 21 so that the toner is pushed back inside the casing 30. Inclined inward in the direction of rotation.

This makes it possible to send the toner toward the end of the developing roller 21 to the inside of the casing 30.

Here, as shown in FIG. 7, the toner seal portion 22b can be formed with a lip portion 22b1 which is in contact with the developing roller 21 along the circumferential direction thereof.

As a result, the toner seal portion 22b comes into contact with the developing roller 21 at the lip portion 22b1, so that the contact area between the two can be reduced, and it becomes possible to prevent an increase in load torque and friction heat.

Here, the lip portion 22b1 can be inclined to the inside of the developing roller 21 so that the contact portion between the developer seal portion and the developing roller is line-contacted. As a result, the toner seal portion 22b comes into contact with the developing roller 21 at the edge of the lip portion 22b1, so that the contact area between the two can be minimized, and an increase in load torque and an increase in friction heat can be prevented. .

In this embodiment, the lip portion 2
2b1 has a height of 0.5 to 2.0 mm and a width of 0.5
Is about 1.5 mm and the tilt angle is about 30 to 60 degrees. Further, the developing roller 2 of the lip portion 22b1
The amount of bite into 1 is set to 0.1 to 0.8 mm.

The lip portion 22b1 provided on the toner seal portion 22b can be provided so as to be inclined so that the toner is pushed back inside the casing 30 with respect to the rotation of the developing roller 21.

Here, when the toner accumulates on the back of the lip portion 22b1, the toner is always heated by frictional heat, so that the toner is melted and fixed. Therefore, it is preferable that the lip portion 22b1 of the toner seal portion 22b, which is in contact with the developing roller 21, does not have a stepped portion inside the developing roller 21 in the width direction. This makes it possible to prevent the toner from staying around the toner seal portion and being fixed by frictional heat.

In this embodiment, the material of the sheet material 36 is urethane rubber, PET film, or the like,
Its thickness is 0.05 mm 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 or part of the sheet material 36 is configured to be in contact with the surface longitudinal direction of the developing roller 21.
It is configured to have a region that intersects with the lip portion 22b1.

As a result, it is possible to prevent the toner seal portion 22b from being carried away by the developing roller 21 and the toner being unable to be sealed. In addition, it is possible to reliably fill the gap between the sheet material 36 and the toner seal portion 22b without using any other member.

Here, the blade portion 22a and the lip portion 22b1 of the toner seal portion 22b which come into contact with the developing roller 21.
When the blade portion 22a is higher than the tip of the lip portion 22b1 of the toner seal portion 22b with respect to the developing roller 21, there is a gap between the lip portion 22b1 of the toner seal portion 22b and the developing roller 21. Toner leaks. On the contrary, when the tip of the lip portion 22b1 of the toner seal portion 22b is higher than the blade portion 22a, there is a gap between the blade portion 22a and the developing roller 21 and toner leakage occurs.

Accordingly, in the present embodiment, the blade portion 22a and the lip portion 22b1 of the toner seal portion 22b with respect to the developing roller 21 in the state where they are incorporated.
Are configured so that their tips are on the same circumference. As a result, the gap between the developing roller 21, the blade portion 22a, and the toner seal portion 22b can be filled, and toner leakage can be prevented.

Here, as described above, conventionally, when the toner sealing means was incorporated into the casing, it was fixed with a double-sided tape or the like. Further, when the toner sealing means is fixed to the casing by using the double-sided tape, there is a problem that it is difficult to re-attach even if an attachment error or a defect occurs.

Therefore, in the present embodiment, as shown in FIG. 9, the width of, for example, 0.5 to 3.0 m is set in the entire area in the circumferential direction of the portion of the toner seal portion 22b which is in contact with the casing 30.
concave groove 22 having a depth of about 1.0 m and a depth of about 1.0 to 4.0 mm
b3 is formed, and further, a convex portion (not shown) is formed in a portion of the casing facing the concave groove 22b3, and they are press-fitted to each other to be attached. The irregularities may be reversed.

As a result, fixing with a double-sided tape or an adhesive becomes unnecessary, and it becomes easy to assemble or reassemble. Further, since both are press-fitted, it is possible to prevent the toner from leaking even in this portion.

Further, as shown in FIGS. 8, 9 and 10, the toner seal portion 22b is provided on the developing roller 21 on the side of the casing 30 at the opposite end to which the blade portion 22a of the toner seal portion 22b is attached. In order to prevent it from being carried away by the rotation of, the anti-rotation protrusion 22b2 also functions as a positioning member. Further, a detent recess (not shown) is formed in a portion of the casing 30 facing the convex portion 22b2, and the both are press-fitted to each other.

Here, nitrile rubber, acrylic rubber, silicon rubber, fluororubber, urethane rubber, tetrafluororesin, etc. are used for the blade / toner seal portion 22, and the friction coefficient of the portion in contact with the developing roller 31 is: The dynamic friction coefficient is 0.1 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 occur such as an increase in load torque of the developing device and an increase in heat due to friction. Then, in order to reduce such a friction coefficient, a method such as applying a Niftron coat to a portion of the toner sealing means portion 22b which is in contact with the developing roller 21 is also adopted.

By the way, the blade portion 22 pressed against the developing roller 21 to thin the toner layer on the developing roller 21.
When an external force is applied to a, there arises a problem that a predetermined layer thickness cannot be obtained or a uniform layer thickness cannot be formed.

Therefore, in the toner seal portion 22b, from the inside of the layer thickness regulation range by the blade portion 22a to the outside of the layer thickness regulation range, there is no portion in contact with the casing 30,
A predetermined amount (for example, 0.5 mm or more) of the gap can be formed. As a result, the blade portion 22a is not affected by the casing 30 via the toner seal portion 22b, so that a uniform layer thickness can be stably formed.

[0066]

As described above, according to the present invention, since the gap generated between the developer layer thickness regulating portion and the developing roller can be filled, the blade is used as the developer layer thickness regulating portion. 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 the work of sticking the developer seal portion is unnecessary, it is possible to obtain an effective effect that the workability can be improved and the work man-hour can be reduced.

Further, according to the present invention, since the developer layer thickness regulating portion and the developer sealing portion are integrally molded with the same elastic member, it is possible to reduce the number of parts and the cost of parts. The effective effect of becoming is obtained.

By inclining the developer seal portion inward in the direction of rotation of the developing roller, the effective effect that the developer toward the end portion of the casing can be sent inward can be obtained.

If a lip portion is formed on the developer seal portion,
Since the developer seal portion comes into contact with the developing roller at the lip portion, the contact area between the developer seal portion and the developing roller is reduced, which makes it possible to prevent an increase in load torque and an increase in friction heat. The effect is obtained.

If the lip portion is inclined to the inside of the developing roller and the contact portion with the developing roller is made into line contact, the developer seal portion comes into contact with the developing roller at the edge of the lip portion. The contact area with the roller can be reduced to the minimum, and an effective effect that the increase in load torque and the increase in friction heat can be prevented can be obtained.

If the step portion is not formed on the inner side in the width direction of the developing roller in the lip portion, it is possible to prevent the developer from staying around the developer seal portion and being fixed by frictional heat. That is an effective effect.

If the tip or a part of the sheet material is arranged so as to contact with the longitudinal direction of the surface of the developing roller and the sheet material and the lip portion have an area intersecting with the circumferential direction of the developing roller, The agent seal part is prevented from being taken off by the friction of the developing roller and becoming impossible to seal,
An effective effect that the gap between the sheet material and the developer seal portion can be surely filled is obtained.

If the developer layer thickness regulating portion and the lip portion are formed on the same circumference with respect to the developing roller, there will be a gap between the developer sealing portion and the developing roller, or the developer layer thickness regulating portion. There is an effective effect that a gap is prevented from being formed between the developing roller and the developing roller.

If the developer seal portion and the casing are fixed by the concave and convex fitting, the developer seal portion can be easily assembled and reassembled in the casing, and the developer can be prevented from leaking at the fitted portion. The effective effect of being possible is obtained.

If the dynamic friction coefficient of the portion of the developer seal portion that comes into contact with the developing roller is set to 0.1 to 0.8, the developer may enter between the developer seal portion and the developing roller and the load of the apparatus may be reduced. An effective effect is obtained in that it is possible to prevent problems such as an increase in torque in advance.

If a gap is formed between the developer seal portion and the casing from within the layer thickness regulation range by the developer layer thickness regulation portion to outside the layer thickness regulation range, the developer layer thickness regulation portion becomes the developer sealing portion. Since it is not affected by the casing through the, it is possible to obtain an effective effect that a uniform layer thickness can be stably formed.

[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.

4 is a perspective view showing an example of a blade / toner seal portion attached to the image forming apparatus of FIG.

5 is a perspective view showing another example of the blade / toner seal portion attached to the image forming apparatus of FIG.

FIG. 6 is a front view of the blade / toner seal portion of FIG.

FIG. 7 is a front view showing a main part of the blade / toner seal portion of FIG.

FIG. 8 is a perspective view showing still another example of the blade / toner seal portion attached to the image forming apparatus of FIG.

FIG. 9 is a perspective view showing still another example of the blade / toner seal portion attached to the image forming apparatus of FIG.

FIG. 10 is a perspective view showing still another example of the blade / toner seal portion attached to the image forming apparatus of FIG.

[Explanation of symbols]

21 developing roller 22 blade / toner seal portion (developer layer thickness regulation / sealing means) 22a blade portion (developer layer thickness regulation portion) 22b toner seal portion (developer seal portion) 22b1 lip portion 23 toner supply roller (supply roller) ) 30 casing 36 sheet material

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-4-345181 (JP, A) JP-A-9-325603 (JP, A) JP-A-9-101677 (JP, A) JP-A-4- 243277 (JP, A) JP-A-8-146761 (JP, A) JP-A-8-179625 (JP, A) Actually open flat 6-16963 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 15/08 505 G03G 15/08 504

Claims (2)

(57) [Claims] 1. A developer with a developing roller for visualizing the electrostatic latent image by supplying a developer to the electrostatic latent image formed on the photosensitive member, the previous SL developing low la mounted rotatably a casing but stored, pressure contact friendly to the developing roller
A layer thickness regulating means is attached to the Noh casing regulates the layer thickness of the developer supplied onto the developing roller
And at least the peripheral surfaces of both ends of the developing roller in the longitudinal direction.
Formed at both ends of the layer thickness regulating means so as to cover a part
And a developer sealing means, the developer sealing means facing the developing roller.
On the inner side in the developing roller width direction on the side of the developing roller.
A developing device having a lip portion formed so as to be contactable . 2. The lip portion of the developer seal means.
Inside the developing roller width direction on the side facing the developing roller
In addition, it is formed so that it can be in line contact with the developing roller.
The rotation of the developing roller
Is provided so that the developer is pushed back to the side.
The developing device according to claim 1, wherein: