JPH08137256A - Developing device - Google Patents

Abstract

PURPOSE: To provide a developing device in which the satisfactory prevention of developer scatter is achieved without bringing a scatter prevention roller into contact with a photoreceptor drum and also without increasing the size of the device. CONSTITUTION: This device is equipped with the scatter prevention roller 41. The scatter prevention roller 41 is provided in the upper part of the opening of a developing container 35 in the gravitational direction so as to free to rotate opposite the photoreceptor drum 14 with a space between them, rotates opposite the photoreceptor drum 14 in the same direction as the direction of the rotation of the photoreceptor drum 14, and also toward the inside of the developing container 35 from opposite the photoreceptor drum 14, and prevents developer, which is scattering when supplied by a developing roller 37, from scattering outside, by allowing the developer to stick to its surface. The device is further equipped with a blade 42 which is provided in a developing container 35 and downstream in the direction of the rotation of the scatter prevention roller 41 and scrapes the developer sticking on the roller 41.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device provided in, for example, an electrophotographic apparatus.

[0002]

2. Description of the Related Art An electrophotographic apparatus forms an electrostatic latent image on a photosensitive drum, and the electrostatic latent image is opposed to a developing device by the rotation of the photosensitive drum, and toner is supplied from the developing device. As a result, the electrostatic latent image is developed.

By the way, in the electrophotographic apparatus, the scattering of the toner can be mentioned as an inevitable adverse effect.

The main location of toner scattering is the developing device, and the phenomenon can be roughly classified into toner scattering to the upper part of the developing device and toner scattering to the lower part of the developing device centering on the developing device.

The toner scattered from the developing device to the inside of the electrophotographic apparatus causes various harmful effects. For example, in the case of toner scattering to the upper part of the developing device, a charging charger, an erasing LED, an optical system, etc. are arranged on the upper part of the developing device.
Various image defects and malfunctions occur.

Further, in the case of toner scattering to the lower part of the developing device, since a transfer charger, a peeling charger, a conveying system, a copy paper, etc. are arranged at the lower part of the developing device, various image defects and Malfunction occurs.

The present invention deals particularly with toner scattering to the upper part of the developing device.

As conventional techniques, the following two methods are roughly classified into methods for preventing toner scattering to the upper part of the developing device.

The first method is to install a scattering prevention seal on the upper part of the developing unit, and to prevent the scattering prevention seal from contacting the photoconductor with no gap.

The second method is a method in which a suction mechanism is provided and the toner scattered by the suction mechanism is sucked to prevent the toner from scattering to the upper portion.

[0011]

However, in the first method, since the scattering prevention seal comes into contact with the photoconductor, the image becomes defective.

That is, since the anti-scattering seal comes into contact with the portion of the photoconductor after charging / exposure and before development, a physical or electric shock is given to the electrostatic latent image formed on the photoconductor, resulting in an image. Is disturbed, and image defects such as white lines occur.

Further, depending on the surrounding environment of the anti-scattering seal or the material and shape of the anti-scattering seal, the anti-scattering seal may not be completely in contact with the photosensitive member, and a non-contact portion may be formed. In this case, the toner is scattered from the non-contact portion, and an image defect occurs in this portion.

On the other hand, in the case of the suction mechanism, there is a problem that the size of the apparatus becomes large and all the scattered toner cannot be sucked.

Therefore, an object of the present invention is to provide a developing device which can prevent the scattering of the developer satisfactorily without bringing the scattering prevention member into contact with the image carrier and without increasing the size thereof. To do.

[0016]

In order to solve the above-mentioned problems, the present invention relates to a first aspect of the present invention, in which an opening is provided so as to face a rotatable image carrier for carrying an image, and a developing device is internally provided. A developer container for containing the developer, a developer supply unit provided inside the developer container for supplying the developer to the image carrier through the opening, and an upper portion of the opening of the developer container in the gravity direction. Is rotatably provided on the side in a state of being spaced apart from and facing the image carrier, and is in the same direction as the rotation direction of the image carrier at a portion facing the image carrier and facing the image carrier. And a scattering prevention member which rotates toward the inner side of the developing container and adheres to the surface of the developer which scatters when the developer is supplied by the developer supplying means to prevent scattering to the outside. Installed inside the developer container, located downstream of the anti-scattering member in the direction of rotation. Is comprises a scraping and to scraping means for scraping off the developer adhered to the anti-scattering member.

According to a second aspect of the present invention, an opening is provided so as to face a rotatable image carrier for carrying an image, a developing container for containing a developer therein, and a developing container are provided inside the developing container. , Rotatable with the developer supply means for supplying the developer to the image carrier through the opening and the upper side of the opening of the developing container in the direction of gravity separated from and facing the image carrier. Is provided in the same direction as the rotation direction of the image bearing member in the facing portion with the image bearing member, and rotates from the facing portion with the image bearing member toward the inner side of the developing container, A scattering prevention member for preventing the scattering of the developer to the outside by adhering the developer scattered when the developer is supplied by the developer supply unit, a voltage applying unit for applying a bias voltage to the scattering prevention member, and the developing unit. Located in the container on the downstream side of the anti-scattering member in the rotation direction. And it provided, comprising a scraping and to scraping means for scraping off the developer adhered to the anti-scattering member.

According to a third aspect of the present invention, an opening is provided so as to oppose a rotatable image carrier for carrying an image, a developing container for containing a developer therein, and a developing container are provided inside the developing container. , Rotatable with the developer supply means for supplying the developer to the image carrier through the opening and the upper side of the opening of the developing container in the direction of gravity separated from and facing the image carrier. Is provided in the same direction as the rotation direction of the image bearing member in the facing portion with the image bearing member, and rotates from the facing portion with the image bearing member toward the inner side of the developing container, A scattering prevention member that adheres the developer scattered when the developer is supplied by the developer supply unit to the surface to prevent the scattering to the outside, and is located in the developing container on the downstream side in the rotation direction of the scattering prevention member. Is installed to scrape off the developer adhering to the scattering prevention member. And Tosu scraping and to scraping means, and control means for controlling the rotational speed of the scattering prevention member according to spacing width between the image carrier and the scatter preventing member.

According to a fourth aspect of the present invention, an opening is provided so as to face a rotatable image carrier for carrying an image, a developing container for containing a developer therein, and a developing container are provided inside the developing container. , Rotatable with the developer supply means for supplying the developer to the image carrier through the opening and the upper side of the opening of the developing container in the direction of gravity separated from and facing the image carrier. Is provided in the same direction as the rotation direction of the image bearing member in the facing portion with the image bearing member, and rotates from the facing portion with the image bearing member toward the inner side of the developing container, A scattering prevention member that adheres the developer scattered when the developer is supplied by the developer supply unit to the surface to prevent the scattering to the outside, and is located in the developing container on the downstream side in the rotation direction of the scattering prevention member. Is installed to scrape off the developer adhering to the scattering prevention member. Comprising the Tosu scraping and to scraping means, and control means to speed up the rotation speed of the anti-scattering member than the rotational speed of the image bearing member.

According to a fifth aspect of the present invention, an opening is provided so as to face a rotatable image carrier for carrying an image, a developing container for containing a developer therein, and a developing container are provided inside the developing container. , Rotatable with the developer supply means for supplying the developer to the image carrier through the opening and the upper side of the opening of the developing container in the direction of gravity separated from and facing the image carrier. Is provided in the same direction as the rotation direction of the image bearing member in the facing portion with the image bearing member, and rotates from the facing portion with the image bearing member toward the inner side of the developing container, A scattering prevention member that adheres the developer scattered when the developer is supplied by the developer supply unit to the surface to prevent the scattering to the outside, and is located in the developing container on the downstream side in the rotation direction of the scattering prevention member. Is installed to scrape off the developer adhering to the scattering prevention member. And Tosu scraping and to scraping means, and control means for controlling the rotational speed of the scattering prevention member according to the charge amount of the developer.

According to a sixth aspect of the present invention, an opening is provided so as to face a rotatable image carrier for carrying an image, a developing container for containing a developer therein, and a developing container are provided inside the developing container. , Rotatable with the developer supply means for supplying the developer to the image carrier through the opening and the upper side of the opening of the developing container in the direction of gravity separated from and facing the image carrier. Is provided in the same direction as the rotation direction of the image bearing member in the facing portion with the image bearing member, and rotates from the facing portion with the image bearing member toward the inner side of the developing container, A scattering prevention member for preventing the scattering of the developer to the outside by adhering the developer scattered when the developer is supplied by the developer supply unit, a voltage applying unit for applying a bias voltage to the scattering prevention member, and the developing unit. Located in the container on the downstream side of the anti-scattering member in the rotation direction. And a scraping unit for scraping off the developer adhering to the anti-scattering member, and a control unit for varying the voltage application amount of the voltage application unit according to the charge amount of the developer. .

[0022]

A scattering prevention member is rotatably provided on the upper side of the opening of the developing container in the direction of gravity so as to face the image carrier, and the scattering developer is attached to the surface of the scattering prevention member. By preventing it from scattering to the outside,
The scattering prevention member prevents the surface of the image carrier from being scratched by contact.

Further, by applying a bias voltage to the anti-scattering member by the voltage applying means, the anti-scattering developer is favorably attached to the anti-scattering member.

Further, by controlling the rotational speed of the anti-scattering member by the control means according to the width of separation between the image carrier and the anti-scattering member, the anti-scattering developer can be favorably attached to the anti-scattering member.

By controlling the rotation speed of the scattering prevention member to be higher than the rotation speed of the image carrier by the control means, the scattered developer can be favorably collected in the developing container.

Further, by controlling the rotation speed of the scattering prevention member by the control means in accordance with the amount of charge of the developer, the scattered developer is favorably collected in the developing container.

Further, the scattered developer is favorably attached to the scattering prevention member by varying the voltage application amount of the voltage application unit by the control unit according to the charge amount of the developer.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings.

FIG. 2 shows an electrophotographic apparatus, and reference numeral 1 in FIG. 2 denotes the apparatus main body. An exposure device 2 is provided on the upper side of the apparatus main body 1. The exposure apparatus 2 includes first and second carriages 3 and 4, an exposure lamp 5 and a first reflection mirror 6 are arranged on the first carriage 3, and a second carriage 4 is provided on the second carriage 4. The second and third reflection mirrors 7 and 8 are arranged. An optical lens 9 is provided in the optical path of the light reflected by the third reflection mirror 8, and the fourth to sixth optical lenses 9 are provided on the light emission side.
Reflective mirrors 10, 11, 12 and slit glass 1
3 are provided.

Further, a photosensitive drum 14 as an image carrier is rotatably provided in the arrow a direction at a substantially central portion of the apparatus main body 1. A charging charger 15, an exposure unit 16, a developing device 17, a transfer and a peeling charger 18, are sequentially arranged around the photosensitive drum 14 along the rotation direction thereof.
19, a cleaning device 20, and a static eliminator 21 are provided.

A paper feed cassette 22 is provided on one side of the apparatus body 1, and a paper discharge tray 23 is provided on the other side. The paper feed cassette 22 and the paper discharge tray 23
Are communicated with each other via the paper transport path 24.

A pickup roller 25 for picking up the paper in the paper feed cassette 22, paper feed / separation rollers 26 and 27, and a registration roller 3 are provided in the paper transport path 24.
1, the transfer peeling chargers 18, 19, the conveyor belt 3
2. A fixing device 28 and a paper discharge roller 29 are provided.

On the upper surface of the apparatus main body 1, there is provided an original placing table 30 on which an original is placed.

During the image formation, the exposure lamp 5 of the first carriage 3 is turned on and the first and second carriages 3 and 4 are moved. This allows
The original document on the original document table 23 is scanned with light, and the reflected light from the original document is reflected by the first to third reflecting mirrors 6 to 8.
After passing through the optical lens 9, this light is applied to the surface of the photosensitive drum 14 through the fourth to sixth reflecting mirrors 10 to 12 and the slit glass 13. The surface of the photosensitive drum 14 is charged by the charging charger 15,
The electrostatic latent image of the original is formed by irradiating the charged surface with the light reflected from the original. This electrostatic latent image is developed by the rotation of the photosensitive drum 14 and the developing device 1
7 and visualized by the developer supplied from the developing device 17.

On the other hand, at this time, the paper is taken out from the paper feed cassette 22 by the rotation of the pickup roller 25, and the paper is fed one by one by the rotation of the paper feed roller 26 and the separation roller 26. This paper is aligned by the registration rollers 31 and then sent to the image transfer portion between the photoconductor drum 14 and the transfer charger 18, and the action of the transfer charger 18 causes an electrostatic latent image on the photoconductor drum 14. Is transcribed.

The sheet on which the electrostatic latent image is transferred is peeled off from the photosensitive drum 14 by the action of the peeling charger 19, and then is conveyed to the fixing device 28 by the traveling of the conveying belt 32 to fix the image. Then, the paper on which the image is fixed is discharged to the discharge tray 23 by the discharge roller 29.

Next, the developing device 17 will be described.

The developing device 17 is provided with a developing container 35 having an opening 35a on the front surface, and the developing container 35 contains a toner and a two-component developer 36 composed of a carrier. Further, in the developing container 35, a developing roller 37 as a developer supplying means for supplying the developer 36 is provided rotatably in the arrow direction, and the developing roller 37 is opposed to the photosensitive drum 14.

Further, the developer 3 is placed in the developing container 35.
A supply roller 38 for supplying 6 to the developing roller 37 is provided, and a mixer 39 for agitating the developer 36 to stabilize the toner concentration in the developer is provided.

A scattering prevention roller 41 as a scattering prevention member is rotatably provided at the upper edge of the opening 35a of the developing container 35 as shown in FIG. The anti-scattering roller 41 is spaced apart and opposed to the photosensitive drum 14, and is in the same direction as the photosensitive drum 14 at the portion facing the photosensitive drum 14 and from the portion facing the photosensitive drum 14 to the developing container 35. It is designed to rotate toward the inside.

Bias voltage applying means 55 is connected to the scattering prevention roller 41 to apply a bias voltage. The bias voltage applying means 55 includes
A control unit 56 is connected, and the control unit 56 controls the amount of voltage applied to the anti-scattering roller 41 according to the amount of charge of the developer.

The developing roller 37 is rotationally driven by the drive motor 57 shown in FIG.
The rotation speed of 7 is controlled by the control means 56. That is, the control means 56 controls the rotation speed of the rotation roller 41 according to the separation width between the photoconductor drum 14 and the anti-scattering roller 41, and also makes it faster than the rotation speed of the photoconductor drum 14. Control is performed in accordance with the charge amount of the developer, and the rotation speed of the scattering prevention roller 41 is controlled by the rotation roller 4.
It is adapted to be controlled in accordance with the voltage application amount for 1.

A scattering prevention roller 4 is provided in the developing container 35.
A blade 42 as a scraping unit is provided in the downstream direction of rotation of 1, and the tip end of the blade 42 is in contact with the surface of the shatterproof roller 41.

A collecting roller 43 is provided in the developing container 35 at the lower end of the opening 35a.
The rotation of the recovery roller 43 allows the developer to be recovered.

Here, the developing device 17 will be described with reference to FIGS.
The drive mechanism of each roller inside will be described.

In the developing device 17, a developing roller gear 45 coaxial with the rotating shaft of the developing roller 37, a first supplying roller gear 46 and a second supplying roller gear 47 provided coaxially with the rotating shaft of the supplying roller 38, An agitating roller gear 48 provided coaxially with the rotating shaft of the agitating mixer 39 and a drive gear 49 for transmitting the rotational force from the drive motor 57 are provided.

The drive gear 49 includes a developing roller gear 45.
And the second supply roller gear 47 mesh with each other at opposite positions. Then, the first supply roller gear 46
And the stirring roller gear 48 mesh with each other. With such a configuration, the rotational force of the drive gear 49 is transmitted to the developing roller gear 45, the first and second supply roller gears 46 and 47, and the stirring roller gear 48, respectively, and the developing roller 37, the supply roller 38, and the stirring mixer 39 are connected to each other. Each is designed to be rotated.

An eccentric cam 50 is provided coaxially with the rotary shaft of the developing roller 37.
Is the recess 5 of the cam follower 51 with respect to the cam follower 51.
The cam 50 is provided so as to fit into the la 1a. A one-way clutch 52 is provided at the end of the follower 51 that is not fitted to the cam 50. The one-way clutch 52 is provided coaxially with the rotation shaft of the scattering prevention roller 41.

By the drive mechanism described above, the cam 50 rotates in the direction of the arrow β in FIG. 3 as the developing roller 37 rotates, which causes the cam follower 51 to rotate the collecting roller 41 as shown in FIG. It rotates about an axis and reciprocates in the direction of r'-r "in the figure.

In the reciprocating motion of the cam follower 51 in the r'-r "direction, when the cam floor 51 rotates in the r" direction in the figure, the force is transmitted to the rotation shaft of the scattering prevention roller 41 by the one-way clutch 52. , Scattering prevention roller 4
1 rotates in the direction of the arrow α in the figure.

The movement of the cam follower 51 in the r'direction is
Due to the action of the one-way clutch 52, it is not transmitted to the scattering prevention roller 41. Therefore, the collecting roller 41 is intermittently rotated in the direction of the arrow in the drawing as the cam 50 rotates with the rotation of the developing roller 37.

However, during development, the mixer 39 is rotated to agitate the developer to stabilize the toner specific density of the developer 36, and then the developer is moved to the supply roller 38, and the rotation of the supply roller 39 causes the development roller to rotate. Sent to 37. The developer 36 sent to the developing roller 37 is the developing roller 3
By the rotation of 7, the toner is supplied to the photosensitive drum 14, and the magnetic toner is supplied to the developing area, which is the contact point between the photosensitive drum 14 and the magnetic developing roller 37, to perform the development.

By the way, at the time of this development, the developing roller 3
A part of the toner supplied by the rotation of 7 scatters upward, and tends to scatter to the outside from the opening 35 a of the developing container 35. The toner that is about to scatter is scattered prevention roller 41 provided at the upper end of the opening 35 a of the developing container 35.
Attached to the surface of the.

The scattering prevention roller 41 is the voltage applying means 5
A predetermined bias voltage is applied by 5 and
The cam 50 is rotated by the drive motor 57 as described above, so that the cam 50 is rotated intermittently.

The toner attached to the anti-scattering roller 41 is conveyed to the blade 42 side by the rotation of the anti-scattering roller 41, scraped off by the blade 42 slidingly contacting the anti-scattering roller 41, and collected in the developing container 35. To be done.

FIG. 6 is a graph showing the relationship between the charge amount of the toner in the developer and the toner scattering.

From the figure, it is understood that the scattering prevention effect (● plot) according to the present invention is equivalent to the scattering prevention effect (◯ plot) when the conventional scattering prevention seal is used.

FIG. 7 shows the relationship between the bias voltage applied to the scattering prevention roller 41 and the toner scattering. Higher bias voltage means less toner scattering.

In the case of this embodiment, the bias voltage seems to be saturated at about 200 V.

As a harmful effect when the bias voltage is set too high, an image defect or the like due to the toner originally supposed to fly to the photoconductor drum 14 adhering to the anti-scattering roller 41 is considered. It is practically impossible to attach importance and apply an excessive bias voltage.

FIG. 8 shows the photosensitive drum 14 and the rotating roller 41.
The relationship between the gap G and the number of rotations of the scattering prevention roller 41 and the toner scattering is shown.

FIG. 8 shows that if the number of revolutions is plotted against a certain gap G, there is no toner scattering to the upper part.

Therefore, the range diagonally to the upper left of the curve in the drawing is the applicable range for setting the gap and the rotational speed when the developer having the toner of each charge amount is used.

[0064]

As described above, according to the present invention, since the anti-scattering member for preventing the developer from scattering upward is provided in a non-contact state with the image carrier, the anti-scattering member may damage the image carrier. It is possible to prevent the occurrence of image defects and the like.

Further, since the bias voltage is applied to the scattering prevention member, it is possible to more reliably prevent the scattering of the developer to the upper portion.

Further, since the rotation speed of the anti-scattering member is varied according to the gap amount between the image carrier and the anti-scattering member, the developer can be prevented from being favorably scattered regardless of the gap amount.

Further, since the rotation speed of the scattering prevention member is made higher than the rotation speed of the image carrier, the scattered developer can be reliably collected in the developing container.

Further, since the rotation speed of the anti-scattering member is varied according to the charge amount of the developer, the scattered developer can be recovered well regardless of the charge amount of the developer.

Further, since the applied amount of the bias voltage is changed according to the charge amount of the developer, the scattered developer can be surely collected regardless of the charge amount of the developer.

[Brief description of drawings]

FIG. 1 is a configuration diagram illustrating a part of a developing device that is an embodiment of the present invention.

2 is a configuration diagram showing an electrophotographic apparatus including the developing device of FIG.

3 is a configuration diagram showing an operation state of a drive system of a scattering prevention roller of the developing device of FIG.

FIG. 4 is a configuration diagram showing an operating state of a drive system of a scattering prevention roller of the developing device of FIG.

5 is a configuration diagram showing an operating state of a drive system of a scattering prevention roller of the developing device of FIG.

6 is a graph showing a relationship between a toner charge amount and a toner scattering level in the developing device of FIG.

FIG. 7 is a graph showing the relationship between the bias voltage and the toner scattering level in the developing device of FIG.

8 is a graph showing the relationship between the gap between the photoconductor and the scattering prevention roller and the number of rotations of the scattering prevention roller in the developing device of FIG.

[Explanation of symbols]

14 ... Photosensitive drum (image bearing member), 35a ... Opening part, 3
5 ... developing container, 37 ... developing roller (developer supply means),
41 ... Scattering prevention roller (scattering prevention member), 42 ... Blade (scraping means).

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location G03G 21/10

Claims (6)

[Claims] 1. A developing container provided with an opening opposed to a rotatable image bearing member carrying an image and containing a developer therein, and the developing container provided inside the developing container, A developer supplying unit that supplies the image carrier through the opening, and a developer supply unit that is rotatably provided on the upper side of the opening of the developing container in the direction of gravity so as to face the image carrier. The developer supply unit rotates in the same direction as the rotation direction of the image bearing member at the portion facing the image bearing member, and from the portion facing the image bearing member toward the inner side of the developing container. A scattering prevention member for preventing the scattering of the developer by adhering the developer scattered at the time of supplying the developer to the surface, and being provided in the developing container at a position downstream of the scattering prevention member in the rotation direction, Scraping off the developer adhering to the scattering prevention member And a dropping unit. 2. A developing container provided with an opening opposed to a rotatable image bearing member carrying an image and containing a developer therein, and the developing container provided inside the developing container, A developer supplying unit that supplies the image carrier through the opening, and a developer supply unit that is rotatably provided on the upper side of the opening of the developing container in the direction of gravity so as to face the image carrier. The developer supply unit rotates in the same direction as the rotation direction of the image bearing member at the portion facing the image bearing member, and from the portion facing the image bearing member toward the inner side of the developing container. A scattering prevention member that adheres the developer scattered when the developer is supplied to the surface to prevent the scattering to the outside, voltage applying means for applying a bias voltage to the scattering prevention member, and the scattering inside the developing container. It is provided at the downstream side in the rotation direction of the prevention member. Developing apparatus is characterized by comprising a scraping and to scraping means for scraping off the developer adhered to the anti-scattering member. 3. A developing container provided with an opening facing a rotatable image carrier for carrying an image and containing a developer therein, and the developing container provided inside the developing container, A developer supplying unit that supplies the image carrier through the opening, and a developer supply unit that is rotatably provided on the upper side of the opening of the developing container in the direction of gravity so as to face the image carrier. The developer supply unit rotates in the same direction as the rotation direction of the image bearing member at the portion facing the image bearing member, and from the portion facing the image bearing member toward the inner side of the developing container. A scattering prevention member for preventing the scattering of the developer by adhering the developer scattered at the time of supplying the developer to the surface, and being provided in the developing container at a position downstream of the scattering prevention member in the rotation direction, Scraping off the developer adhering to the scattering prevention member A developing device comprising: a drop unit; and a control unit that controls a rotation speed of the scattering prevention member according to a separation width between the image carrier and the scattering prevention member. 4. A developing container provided with an opening opposed to a rotatable image bearing member carrying an image and containing a developer therein, and the developing container provided inside the developing container. A developer supplying unit that supplies the image carrier through the opening, and a developer supply unit that is rotatably provided on the upper side of the opening of the developing container in the direction of gravity so as to face the image carrier. The developer supply unit rotates in the same direction as the rotation direction of the image bearing member at the portion facing the image bearing member, and from the portion facing the image bearing member toward the inner side of the developing container. A scattering prevention member for preventing the scattering of the developer by adhering the developer scattered at the time of supplying the developer to the surface, and being provided in the developing container at a position downstream of the scattering prevention member in the rotation direction, Scraping off the developer adhering to the scattering prevention member A developing device comprising: a dropping unit; and a control unit that makes the rotation speed of the scattering prevention member faster than the rotation speed of the image carrier. 5. A developing container having an opening opposed to a rotatable image bearing member carrying an image and containing a developer therein, and the developing container provided inside the developing container. A developer supplying unit that supplies the image carrier through the opening, and a developer supply unit that is rotatably provided on the upper side of the opening of the developing container in the direction of gravity so as to face the image carrier. The developer supply unit rotates in the same direction as the rotation direction of the image bearing member at the portion facing the image bearing member, and from the portion facing the image bearing member toward the inner side of the developing container. A scattering prevention member for preventing the scattering of the developer by adhering the developer scattered at the time of supplying the developer to the surface, and being provided in the developing container at a position downstream of the scattering prevention member in the rotation direction, Scraping off the developer adhering to the scattering prevention member A developing device, comprising: a dropping unit; and a control unit that controls a rotation speed of the scattering prevention member according to a charge amount of the developer. 6. A developing container provided with an opening opposed to a rotatable image bearing member carrying an image and containing a developer therein, and the developing container provided inside the developing container, A developer supplying unit that supplies the image carrier through the opening, and a developer supply unit that is rotatably provided on the upper side of the opening of the developing container in the direction of gravity so as to face the image carrier. The developer supply unit rotates in the same direction as the rotation direction of the image bearing member at the portion facing the image bearing member, and from the portion facing the image bearing member toward the inner side of the developing container. A scattering prevention member that adheres the developer scattered when the developer is supplied to the surface to prevent the scattering to the outside, voltage applying means for applying a bias voltage to the scattering prevention member, and the scattering inside the developing container. It is provided at the downstream side in the rotation direction of the prevention member. Scraping means for scraping off the developer adhering to the scattering prevention member, and control means for varying the voltage application amount of the voltage application means in accordance with the charge amount of the developer. Developing device.