JP2003167428A - Developing device, process cartridge and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent toner from being stuck to the edge of a thin layer forming member on a downstream side and to prevent image quality from being deteriorated because the stuck toner drops onto a developer carrier without mounting a special device such as a paper powder removing device nor costing much in an image forming apparatus. <P>SOLUTION: In this developing device 12 for the image forming apparatus, developer carried on a developing sleeve (developer carrier) 28 is made to be a thin layer by a developing doctor (thin layer forming member) 29, and the developer made to be the thin layer is stuck to a latent image on a photoreceptor (image carrier) 10 so as to develop the latent image. In the device 12, a developer scattering preventing member (adjacent member) 50 is provided adjacently to the downstream side of the developing doctor in the rotating direction B of the developing sleeve. The developing doctor side of the opposed surface 58 of the member 50 opposed to the developing sleeve and the edge of the developing doctor are provided at an equal distance from the developing sleeve. The opposed surface is gradually separated from the peripheral surface of the developing sleeve toward the downstream side in the rotating direction of the developing sleeve. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile, or a combination thereof. In particular, transfer the toner image formed on the image carrier by charging, optical writing, and development,
The present invention relates to an electrophotographic image forming apparatus that records an image on a transfer material such as a sheet or an intermediate transfer body. Further, the present invention relates to a developing device for developing a latent image on an image carrier in such an image forming apparatus, and a process cartridge including the developing device and at least the image carrier, which is detachable from the image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, in a developing device which uses a dry two-component developer composed of a carrier and a toner in an electrophotographic image forming apparatus, the developing device accommodated in a developing case 1 as shown in FIG. The developer is scraped up by the rotation of the paddle 2 and adhered to the developer carrying member 3, and the developer carrying member 3
Along with the rotation of the developer, the developer carried on the developer is thinned.
Then, the electrostatic latent image on the image bearing member 5 was developed by applying a thinned developer to the electrostatic latent image.

By the way, in this type of developing device, a developer scattering prevention member 6 is provided adjacent to the downstream side of the layer thinning member 4 in the rotation direction B of the developer carrier 3, and the developer scattering prevention member 6 is provided. And the inlet seal 7 made of polyurethane etc.
8 was held, and a facing surface 9 facing the developer carrying member 3 was formed on it.

Then, in order to prevent the developer on the developer carrying member 3 after being thinned by the thinning member 4 from coming into contact with the facing surface 9 of the developer scattering preventing member 6 from the tip of the thinning member 4. The developer carrying member 3 was retracted to a position away from the peripheral surface. For this reason,
A step s was formed at the downstream end of the layer-thinning member 4 in the rotation direction B of the developer carrying member 3.

Therefore, for example, as shown in FIG. 10, the developer adheres to the stepped portion s and accumulates as t with the passage of time, and eventually solidifies and is solidified by impact or the like. There is a problem that the image drops on the transfer material and causes image distortion on the transfer material.

[0006]

[Patent Document 1] Japanese Unexamined Patent Publication No. 5-2340

[Patent Document 2] Japanese Unexamined Patent Publication No. 5-2341

[Patent Document 3] Japanese Unexamined Patent Publication No. 10-161496 In order to solve such a problem, for example, in those disclosed in Japanese Unexamined Patent Publication Nos. 5-2340 and 5-2341, the rotational direction of the developer carrying member is set. The magnitude and the polarity of the magnetic force of the developer carrying member are changed between the upstream side and the downstream side of the thin layer forming member. Further, for example, in the one described in Japanese Patent Laid-Open No. 10-161496, the toner having a small charge amount containing a large amount of paper powder in the developer spike is removed from the developer spike by the centrifugal force generated by the rotation of the magnetic roller. Have been removed.

[0007]

However, although the former is effective in fixing toner to the tip surface of the thinning member, it is sufficient for toner adhesion to the downstream tip and the developer scattering prevention member. The effect was not obtained. In the latter case, when the amount of collected toner located near the magnetic roller increases, it becomes difficult to adsorb only the normally charged toner.
Foreign matter such as paper dust will be mixed into the developer spikes,
Similarly, a sufficient effect was not obtained.

Therefore, a first object of the present invention is, in the image forming apparatus as described above, without installing a special device such as a paper dust removing device, at a low cost, and downstream of the thinning member. It is to prevent the toner from adhering to the tip of the side and to prevent the adhered toner from dropping onto the developer carrier and deteriorating the image quality.

A second object of the present invention is to prevent the toner from accumulating on the downstream end of the thinning member by being covered with the developer scattering prevention member adjacent to the thinning member, and the toner adhered thereto. Is to prevent the toner from falling on the developer carrying member and degrading the image quality.

A third object of the present invention is to ensure a space between the surface of the developer and the opposite surface so that blocking does not occur even when the toner stands up, and a thinning member is used to form a thin layer on the developer carrying member. The object is to provide a good image without disturbing the toner.

A fourth object of the present invention is to provide a cleaning effect by conveying the toner while keeping the tip of the raised toner in contact with the facing surface of the developer scattering prevention member in accordance with the rising of the toner. Prevents toner from adhering to the opposite surface,
The purpose of this is to prevent the adhered toner from dropping onto the developer carrying member and deteriorating the image quality.

A fifth object of the present invention is to provide a process cartridge having improved maintainability in addition to the above-mentioned objects.

By the way, in recent years, in the image forming apparatus, from the viewpoint of environmental protection and reduction of running cost, a toner recycling apparatus for recovering untransferred toner to a transfer material such as a sheet or an intermediate transfer member and returning it to the developing apparatus. Those equipped with are becoming common.

However, in such an image forming apparatus,
Foreign matter such as paper powder attached to the image carrier or the intermediate transfer body during transfer is mixed in the recycled toner. The mixed paper powder is subjected to a large amount of mechanical stress by the conveying member and the like and is ground into fine powder before being returned to the developing device and reused. The crushed paper powder has a small amount of charge, and when the amount of paper powder with a small amount of charge that cannot be held by the carrier increases in the developer with the passage of time, the toner containing a large amount of the paper powder scatters and is deposited on the step s. accumulate.

Particularly in recent years, since the number of users who use paper with a large amount of paper dust such as recycled paper has increased, toner containing a large amount of paper dust is further scattered and accumulated,
There is a problem that it solidifies and then falls onto the developer bearing member due to impact or the like, causing image disorder on the transfer material.

Further, in an image forming apparatus equipped with a toner recycling device, the content rate of paper powder in the developer increases with the passage of time. Therefore, when the process cartridge is about to be replaced due to the life of the image carrier, the content of paper powder in the developer also increases.

Then, the amount of low-charged toner increases, and the background stain level becomes worse than in the initial stage. Even if the image carrier or the toner recycling device is replaced in this state, the developer in the developing device contains a large amount of paper dust, so that the initial image is not good and the background stain is accelerated.

This is because only the developing device and the developer are replaced,
The same applies when the toner recycling device is not replaced.
As described above, if the replacement cycle is different, there is a problem that a good image cannot be obtained even in the initial stage.

Therefore, a sixth object of the present invention is to say that even in a process cartridge provided with a toner recycling device which is liable to cause toner adhesion due to the inclusion of foreign matter such as paper powder as described above, it goes without saying that the process cartridge does not stand in the initial stage. In addition, it is necessary to prevent the toner from adhering to the downstream end of the layer-thinning member and the member adjacent thereto, and to effectively prevent the adhered toner from dropping on the developer carrier and degrading the image quality. It is in.

A seventh object of the present invention is to provide an image forming apparatus equipped with a developing device which achieves the above-mentioned first to fourth objects.

An eighth object of the present invention is to provide an image forming apparatus equipped with a toner recycling device which is liable to cause toner adhesion due to the inclusion of foreign matter such as paper powder as described above. To prevent the toner from adhering to the member adjacent thereto and effectively prevent the adhered toner from dropping onto the developer carrier and deteriorating the image quality.

A ninth object of the present invention is to provide an image forming apparatus provided with a process cartridge which achieves the above fifth or sixth object.

[0023]

Therefore, according to the invention of claim 1, in order to achieve the above-mentioned first object, the developer carried on the developer carrying member is thinned by a thinning member, In the developing device of the image forming apparatus, which develops the latent image on the image carrier by adhering the developer after the thinning, adjacent to the downstream side of the thinning member in the moving direction of the developer carrier. An adjacent member is provided, and the thinning member side of the facing surface of the adjacent member facing the developer carrying member and the tip of the thinning member are provided at an equal distance from the developer carrying member. Is characterized by.

In order to achieve the above-mentioned second object, the invention according to claim 2 is the developing device according to claim 1, wherein
As a neighboring member, a developer scattering prevention member for covering the developer carrying member to prevent the developer scattering is provided.

According to a third aspect of the invention, in order to achieve the third object described above, in the developing device according to the second aspect,
It is characterized in that the opposite surface of the developer scattering prevention member is gradually separated from the developer carrying body toward the downstream side in the moving direction of the developer carrying body.

In order to achieve the above-mentioned fourth object, the invention according to claim 4 is the developing apparatus according to claim 3, wherein:
It is characterized in that the facing surface is equidistant from the developer carrying member from the middle on the downstream side in the moving direction of the developer carrying member.

According to a fifth aspect of the present invention, in order to achieve the fifth object described above, in the process cartridge, the developing device according to any one of the first to fourth aspects and at least an image carrier are provided in one cartridge. It is characterized in that it is provided in a case and is detachable from the main body of the image forming apparatus.

In order to achieve the above-mentioned sixth object, the invention according to claim 6 is, in the process cartridge according to claim 5, a toner recycling device for recovering untransferred toner to a transfer material and returning it to the developing device. It is characterized by comprising.

According to a seventh aspect of the invention, in order to achieve the seventh object described above, the image forming apparatus includes the developing device according to any one of the first to fourth aspects. To do.

In order to achieve the above-mentioned eighth object, the invention according to claim 8 is the image forming apparatus according to claim 7, in which toner recycle to the transfer material is recovered and returned to the developing device. It is characterized by comprising a device.

According to a ninth aspect of the invention, in order to achieve the ninth object described above, an image forming apparatus is provided with the process cartridge according to the fifth or sixth aspect.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a main part of a laser copying machine according to the present invention.

In the figure, reference numeral 10 is a drum-shaped photosensitive member which is an image bearing member. As can be seen from FIG. 1, around the photoconductor 10, the roller-shaped charging device 11 provided on the side of the photoconductor 10 to the developing device 12 on the lower side and the transfer device 13 on the side in order in the rotation direction of the photoconductor 10 indicated by the arrow A. A paper separating device 14 and a cleaning device 15 are provided on the paper separating device 14.

When making a copy, as is well known, the document is set on a contact glass (not shown), the copy switch is pressed, and the image of the document is read by an optical reading device (not shown), and at the same time, the photoconductor is read. Paper (transfer material) P is fed between 10 and the transfer device 13.

On the other hand, the photoconductor 10 rotates at a predetermined peripheral speed, and the surface of the photoconductor 10 is uniformly charged by the charging device 11 that cleans with the cleaning pad 16 according to the rotation, and an optical writing device (not shown) is provided on the surface. Laser beam L is used for writing to form an electrostatic latent image of the read original image on the photoconductor 10 and toner is attached to the electrostatic latent image when passing through the developing device 12 position. Images are made visible one after another. Then, the transfer device 13 transfers the toner image formed as a visible image onto the sheet P conveyed between the photoconductor 10 and the transfer device 13 as described above.

After the transfer, the paper P is discharged by the paper separating device 14 to be separated from the electrostatically adhered photoconductor 10 and conveyed to a fixing device (not shown) to fix the transferred image there, and the transfer image is not shown. To the paper output section of. Instead of the sheet separating device 14, a separating claw may be provided to mechanically separate the photosensitive member 10.

On the other hand, the residual toner remaining on the surface of the photoconductor 10 after the image transfer is scraped off by the cleaning blade 17 provided in the cleaning device 15 to clean the surface, and then the charge is removed by a charge removing lamp (not shown). Initialize the surface potential.

By the way, in the illustrated example, the photosensitive member 1 described above is used.
0, charging device 11, developing device 12, and cleaning device 1
5 and 5 are provided in one cartridge case 19 to form a process cartridge 20. Then, as shown in FIG. 2, the process cartridge 20 is inserted into and removed from the copying machine main body 18 from the front side in the direction of the arrow so as to be detachable.

Now, such a process cartridge 2
0, the developing device 12 described above is configured by providing the developer accommodating portion 21 on the lower side and the developer carrying portion 22 on the upper side, as shown in FIG. In the developer accommodating portion 21,
A stirring member 23 for accommodating a dry two-component developer including a carrier and a toner and conveying the developer while stirring is provided. Although not shown, a toner concentration sensor for detecting the mixing ratio of the toner in the developer and the carrier is provided.

On the other hand, the developer carrying portion 22 has a developing window 27.
A developing sleeve (developer carrying member) 28 having a magnet inside is provided at a position opposed to the photoconductor 10 through. Further, a developing doctor (thin layering member) 29 for controlling the supply amount of the developer to the photoconductor 10 is provided.

In the cleaning device 15 provided on the photosensitive member 10, a recovery blade 30 for scraping the residual toner scraped off by the cleaning blade 17 into the cleaning case portion 19a of the cartridge case 19, and the recovery blade 30 scrapes the toner. As shown in FIG. 3, the coiled toner conveying member 31 conveys the raised residual toner in the axial direction of the photoconductor 10.

Then, the toner collected by the cleaning device 15 is passed through the process cartridge 20 to the process cartridge 20 through a transfer passage formed of a pipe or the like, and a developing member is used by using a conveying member such as a screw, a coil or a belt or by utilizing gravity. A toner recycling device 32 for returning the toner to the developer container 21 is provided.

In the developing device 12, at the time of copying, a drive motor (not shown) is driven, the drive is transmitted to rotate the developing sleeve 28, and the stirring member 23 is rotated to stir the developer, and the toner The carrier is conveyed to the developing sleeve 28 while being frictionally charged. On the other hand, the developing sleeve 2
A predetermined bias is applied to 8 to electrostatically attach the toner in the developer to the surface of the photoconductor 10 to visualize the latent image on the surface.

On the other hand, in the cleaning device 15, the rotation of the photoconductor 10 is transmitted through the gears to transmit the toner carrying member 30.
Is rotated, and the residual toner removed from the photoconductor 10 is conveyed by the toner conveying member 30 so that the cleaning case portion 19
The toner is collected on the front side in a and returned to the developing device 12 by the toner recycling device 32.

FIG. 4 is an enlarged view of a part of the developing device 12 provided in the process cartridge 20.

As shown in FIG. 4, in the developing device 12 of the illustrated laser copying machine, the photoconductor 10 which is an image carrier rotates in the direction A (counterclockwise in the figure), and the developing sleeve which is a developer carrier. 28 rotates in the B direction (clockwise in the figure).

The tip of a developing doctor 29, which is a thinning member, faces the developing sleeve 28. The developing doctor 29
The base end is bent upward with a thin metal plate to form an L-shaped cross section, which is arranged horizontally along the axial direction of the developing sleeve 28, and both ends are supported by support plates (not shown).

On the downstream side of the developing doctor 29 in the rotating direction B of the developing sleeve 28, a developer scattering prevention member 50 is provided adjacent to the developing doctor 29 with a small gap of preferably 0.5 mm or less, Then the developing sleeve 28
To prevent the developer from scattering.

As shown in FIG. 5, the developer splattering preventive member 50 is made of a slender plate and is reinforced by a plurality of reinforcing fins 51. The base end of a film-like inlet seal 55 is attached on one side, and the bottom side of the one side is attached. The base end of another inlet seal 56 in the form of a film is attached to, and both ends are screwed to a supporting member (not shown) that supports the developing sleeve 28 and the developing doctor 29, and the upper portion of the developing sleeve 28 is covered.

This developer scattering prevention member 50 is applied to the developing device 1.
When it is attached to No. 2, the tips of the inlet seals 55 and 56 are brought into contact with the peripheral surface of the photoconductor 10. Further, when attached to the developing device 12, a facing surface 58 is formed at a portion facing the peripheral surface of the developing sleeve 28. The opposing surface 58 of the developing doctor 29 and the tip of the developing doctor 29 are provided at an equal distance from the peripheral surface of the developing sleeve 28, and the downstream tip of the developing doctor 29 in the rotation direction B of the developing sleeve 28 is provided. The developer splattering prevention member 50 is completely covered to eliminate the stepped portion s conventionally formed there.

As a result, the toner scattered around the developing sleeve 28 is provided downstream of the developing doctor 29 in the rotation direction B of the developing sleeve 28 without mounting a special device such as a paper dust removing device and at a low cost. It is possible to prevent the toner from adhering to and depositing on the side tip, and prevent the adhered toner from dropping onto the developing sleeve 28 and deteriorating the image quality.

By the way, the side of the developing doctor 29 of the facing surface 58 and the tip of the developing doctor 29 are connected to the developing sleeve 28.
If the gap between the opposing surface 58 and the peripheral surface of the developing sleeve 28 is left as it is to the downstream side in the rotation direction B of the developing sleeve 28, the space for transporting the toner becomes small and the blocking of the developer and The entrance seals 55 and 56 are peeled off.

Therefore, as shown in FIG. 6, the facing surface 58 of the developer scattering prevention member 50 may be gradually separated from the developing sleeve 28 toward the downstream side in the rotation direction B of the developing sleeve 28.

In this way, a space is secured between the facing surface 58 and even if the toner stands up, blocking does not occur and the entrance seals 55 and 56 do not come off, and the developing doctor 29 makes a thin layer. A good image can be provided without disturbing the toner on the developing sleeve 28 later.

In the developing device 12 as described above, when the tip of the spike of the toner formed on the developing sleeve 28 comes into contact with the facing surface 58, the toner adhering to the facing surface 58 is removed to provide a cleaning effect. You can have it. Therefore,
It is desirable that the facing surface 58 that gradually separates from the developing sleeve 28 is not separated from the developing sleeve 28 by a certain amount or more after the middle of the developing sleeve 28 on the downstream side in the rotation direction B.

Now, as shown in FIG. 7, the developing sleeve 2
The magnetic flux density distribution curves in the normal direction around 8 are a to e, and between the developer carrying pole P4 of the developing sleeve 28 arranged on the upstream side of the developing doctor 29 and the developer carrying pole P5 of the developing sleeve 28 arranged on the downstream side. Let f be the tangential magnetic flux density distribution curve of.

Further, the distribution curve f and the developer transport pole P
5 where Q is the intersection with the distribution curve e, and L is the line connecting the intersection Q and the rotation center O of the developing sleeve 28,
The intersection of the line L and the facing surface 58 is P, and the line L and the developing sleeve 2 are
8 Let R be the intersection with the surface. Further, the intersection of the normal line M of the developer carrying pole P5 and the facing surface 58 is X, and the intersection of the normal line M and the surface of the developing sleeve 28 is Y.

Then, as shown in FIG. 8, the spikes of the toner at the intersection R start to rise with an inclination of 45 ° with respect to the tangential direction. Then gradually rise,
It rises at 90 ° to the tangential direction at the intersection point Y.

Therefore, at the position adjacent to the developing doctor 29, the facing surface 58 is formed with a radius R1 centered on the rotation center O, and the intersection P on the downstream side in the rotation direction B of the developing sleeve 28.
After that, the radius is gradually increased, and after the intersection point X on the downstream side, the radius R2 is larger than the radius R1 and the intervals are again equal to the developing sleeve 28.

In this way, the toner is conveyed while the leading edge of the toner that has risen is always in contact with the facing surface 58 of the developer scattering prevention member 50 in accordance with the rising of the toner, and the facing surface is provided with a cleaning effect. It is possible to prevent toner from adhering to 58 and prevent the adhering toner from dropping onto the developing sleeve 28 and degrading the image quality.

In the illustrated example, in the image forming apparatus including the toner recycling device 32 in which foreign matter such as paper dust is easily mixed to cause toner adhesion, the downstream end of the developing doctor 29 or the developer scattering preventing member adjacent thereto. Toner is prevented from adhering to 50, effectively preventing the adhered toner from dropping onto the developing sleeve 28 and degrading the image quality.

Here, in the illustrated example, in the image forming apparatus provided with the toner recycling device 32 for collecting the toner from the cleaning device 15 for the photoconductor 10, the developing doctor 2 is used.
9 and the toner scattering prevention member 50 were prevented from adhering the toner to effectively prevent the deterioration of the image quality.

However, not limited to such an image forming apparatus, for example, an image in which a toner image on an image carrier is once transferred onto an intermediate transfer member, which is a transfer material, and then transferred onto a sheet such as paper or OHP film. The image forming apparatus is applied to an image forming apparatus that includes a toner recycling device 32 that collects toner from a cleaning device for an intermediate transfer member in the forming apparatus, and prevents toner from adhering to the developing doctor 29 and the developer scattering prevention member 50, thereby deteriorating the image quality. Can be effectively prevented.

[0064]

As described above, according to the first aspect of the invention, the adjoining member provided adjacent to the downstream side of the thinning member in the moving direction of the developer carrying member faces the developer carrying member. Since the thinning member side of the facing surface and the tip of the thinning member are provided at the same distance from the developer carrying member, the step portion of the downstream end of the thinning member is eliminated and the toner is stored there. It is possible to prevent the accumulation.

This prevents toner from adhering to the downstream end of the layer-thinning member without developing a special device such as a paper dust removing device, and developing the adhered toner without cost. It is possible to prevent the image quality from being lowered by dropping onto the agent carrier.

According to the second aspect of the present invention, since the developer scattering prevention member for covering the developer carrying member to prevent the developer scattering is provided as the adjacent member, it is possible to prevent the developer scattering adjacent to the thinning member. It is possible to prevent the toner from accumulating on the downstream end of the layer-thinning member by being covered with the member, and to prevent the toner adhering thereto from dropping on the developer carrier and deteriorating the image quality.

According to the third aspect of the invention, since the facing surface of the developer scattering prevention member is gradually separated from the developer carrying member toward the downstream side in the moving direction of the developer carrying member, it is provided between the facing surface. Even if the toner is erected to secure the space, blocking does not occur and the entrance seal does not peel off, and the thinning member does not disturb the toner on the developer carrier after thinning, and a good image is obtained. Can be provided.

According to the invention of claim 4, the opposing surface is
From the middle of the downstream side in the direction of movement of the developer carrier, the distance from the developer carrier will be equidistant, so the tip of the spiked toner will always contact the facing surface of the developer scattering prevention member according to the spike of toner. While carrying the toner, it is possible to prevent the toner from adhering to the opposite surface by providing a cleaning effect and prevent the adhered toner from dropping on the developer carrier and deteriorating the image quality. .

According to the fifth aspect of the present invention, a process cartridge is formed by including the developing device according to any one of the first to fourth aspects and at least the image carrier in a cartridge case to form an image. Since it is detachable from the apparatus main body, it is possible to improve the above-mentioned effects and maintainability.

According to the sixth aspect of the invention, the process cartridge is provided with the toner recycling device for collecting the untransferred toner on the transfer material and returning it to the developing device.
Even in a process cartridge equipped with a toner recycling device that easily causes toner adhesion due to the inclusion of foreign matter such as paper dust, the developing device and the toner recycling device can be replaced at the same time, and the layer is thinned not only in the initial stage but also over time. It is possible to prevent the toner from adhering to the downstream end of the member or the member adjacent thereto, and to effectively prevent the adhered toner from dropping onto the developer carrier and degrading the image quality.

According to the seventh aspect of the present invention, since the developing device according to any one of the first to fourth aspects is provided, it is possible to provide the image forming apparatus including the developing device having each of the above effects. it can.

According to the eighth aspect of the present invention, the image forming apparatus is provided with the toner recycling device for collecting the untransferred toner on the transfer material and returning it to the developing device. Even in an image forming apparatus equipped with a toner recycling device that tends to adhere, toner adhesion is prevented from adhering to the downstream end of the layer-thinning member and adjacent members, and the adhered toner falls onto the developer carrier. It is possible to effectively prevent deterioration of image quality.

According to the ninth aspect of the invention, since the process cartridge according to the fifth or sixth aspect is provided, it is possible to provide an image forming apparatus provided with the process cartridge having each of the above effects.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a main part of a laser copying machine according to the present invention.

FIG. 2 is a perspective view showing attachment and detachment of the process cartridge.

FIG. 3 is a perspective view illustrating a toner recycling device provided in the process cartridge.

FIG. 4 is a partially enlarged view of a developing device included in the laser copying machine.

FIG. 5 is a perspective view of a developer scattering prevention member used in the developing device.

FIG. 6 is a further enlarged view of a part of the developing device.

FIG. 7 is an explanatory diagram illustrating a shape of a facing surface of the developer scattering member.

FIG. 8 is an explanatory diagram illustrating a toner spike state by enlarging a part thereof.

FIG. 9 is a partially enlarged view of a conventional developing device.

FIG. 10 is a further enlarged view of a part of the conventional developing device.

[Explanation of symbols]

10 Photoconductor (image carrier) 12 Development device 18 Copier machine body (image forming machine body) 19 cartridge case 20 process cartridges 28 Development Sleeve (Developer Carrier) 29 Development Doctor (Thinning member) 32 Toner recycling device 50 Developer scattering prevention member (adjacent member) 58 Opposing surface

Claims (9)

[Claims] 1. An image forming method in which a developer carried on a developer carrying member is thinned by a thinning member, and the thinned developer is attached to develop a latent image on the image carrying member. In the developing device of the apparatus, an adjacent member is provided adjacent to the downstream side of the thinning member in the moving direction of the developer carrier, and the thin surface of the adjacent member facing the developer carrier is provided. A developing device in which the layered member side and the tip of the layered member are provided at an equal distance from the developer carrying member. 2. The developing device according to claim 1, further comprising, as the adjoining member, a developer scattering prevention member that covers the developer carrier to prevent the developer scattering. 3. The developing device according to claim 2, wherein the facing surface of the developer scattering prevention member is gradually separated from the developer carrying body toward the downstream side in the moving direction of the developer carrying body. 4. The developing device according to claim 3, wherein the facing surface is equidistant from the developer carrying body from a point on the downstream side in the moving direction of the developer carrying body. 5. A process cartridge comprising the developing device according to any one of claims 1 to 4 and at least the image carrier in a cartridge case, and is detachable from the main body of the image forming apparatus. 6. The process cartridge according to claim 5, further comprising a toner recycling device that collects untransferred toner on the transfer material and returns it to the developing device. 7. An image forming apparatus comprising the developing device according to claim 1. Description: 8. The image forming apparatus according to claim 7, further comprising a toner recycling device that collects untransferred toner on the transfer material and returns it to the developing device. 9. An image forming apparatus comprising the process cartridge according to claim 5 or 6.