JP2778521B2 - Image forming device - Google Patents

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,
In particular, the present invention relates to an image forming apparatus capable of reusing toner used for image formation in a printer, a facsimile, a copying machine, or the like using an electrophotographic process.

[0002]

2. Description of the Related Art Conventionally, this type of image forming apparatus includes:
For example, as shown in FIG. 3, a photosensitive drum 50 on the surface of which an electrostatic latent image is formed, a toner hopper 56 containing a toner 52 and having a mixer 54 therein, and an opening 58 through the toner hopper 56 Developing chamber 60
And are provided. A developing roller 62 for supplying the toner 52 to the photosensitive drum 50 and a toner 52 from the toner hopper 56 are attached to the developing roller 62.
Is provided with a supply roller 64 for supplying the toner.

In such a conventional example, the toner 52 sent out by a mixer 54 from a toner hopper 56 is used.
Is supplied to the supply roller 64, is supplied to the developing roller 62 by the supply roller 64, and is finally supplied to the photosensitive drum 50 so that the electrostatic latent image is visualized.

[0004]

In this type of image forming apparatus, the toner 52 is charged to a certain level by the supply operation of the supply roller 64. Affect.
Therefore, from the viewpoint of unifying the charging path, the toner 52 sent out from the toner hopper 56
It is an ideal condition for obtaining high image quality to be supplied to the developing roller 62 only by the above operation.

However, in the above-described prior art, when focusing on the supply state of the toner 52 from the toner hopper 56 to the developing roller 62, the situation is different from the ideal condition.

That is, the developing roller 62 and the toner hopper 56
Is open, the toner flows from the supply roller 64 to the developing roller 62 in addition to the original toner flow, and as shown by the arrow D, the toner 52 There is a flow that directly adheres to the developing roller 62 without passing through the supply roller 64.

Further, it has been confirmed that the toner 52 sequentially sent from the toner hopper 56 stays in the developing chamber 60 around the developing roller 62 and the supply roller 64, and the toner 52 directly rides on the developing roller 62.

As described above, in the above-described conventional example, since two flows which directly reach the developing roller 62 occur in addition to the original toner flow, the toners having different charged states adhere to the developing roller 62 due to the respective flows. . When the toners having different charged states coexist, the toner is developed in a state in which the amount of toner adhered is partially insufficient, so that there is a disadvantage that the print quality is deteriorated.

When the toner is accumulated in the developing chamber 60 and the supply roller 62 is made of a foamed material, the toner enters the cell too much and the supply roller 3 is hardened. There was a disadvantage that the supply could not be performed sufficiently, or the developing roller 62 was scraped to shorten the life.

[0010] These problems are caused by the fact that the space between the developing roller and the toner hopper has an open structure. To cope with this, if the space of the developing chamber is narrowed, this time, The supply of toner from the toner hopper to the supply roller is hindered.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to improve the disadvantages of the prior art, to obtain a uniform charge state of toner without obstructing toner supply from a toner hopper to a supply roller, and to improve print quality. It is an object of the present invention to provide an image forming apparatus that can be improved.

Another object of the present invention is to provide an image forming apparatus capable of preventing a supply roller from being hardened and supplying an appropriate amount to a developing roller and extending its life.

[0013]

SUMMARY OF THE INVENTION According to the present invention, there is provided a photosensitive drum having an electrostatic latent image formed on a surface thereof, a developing roller for supplying toner to the photosensitive drum, and containing the toner and sending out the toner. In an image forming apparatus comprising: a toner hopper having a mixer; and a supply roller for supplying the toner sent from the toner hopper to the developing roller, the toner sent from the toner hopper is disposed between the toner hopper and the developing roller. A configuration is adopted in which a partitioning means for preventing the roller from directly reaching the roller is provided.

Further, the above-mentioned partitioning means includes a partition plate provided above the supply roller, and a plurality of toner passage areas provided between the partition plate and the supply roller and rotating in contact with the supply roller. And a scraper mechanism provided.

[0015] Then, the above-mentioned scraper mechanism, substantially parallel to the rotation axis to the axis of the feed roller, at intervals in the longitudinal direction to the rotation axis constituted by a plurality obtained disc-like inclined blades, that The method is adopted. This aims to achieve the above-mentioned object.

[0016]

In the above invention, the toner sent from the toner hopper is blocked from flying directly to the developing roller by the partition member, and is incorporated into the original flow to the supply roller. As a result, the flow of the toner to the developing roller is unified, and the charged state of the toner is made uniform and supplied to the developing roller.

Further, the contact rotation of the scraper mechanism and the supply roller in the biting state prevents the toner from entering the supply roller and scrapes the entered toner.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

The image forming apparatus 2 includes a photosensitive drum 4 on which an electrostatic latent image is formed on a surface thereof, a toner hopper 10 having a mixer 8 which accommodates the toner 6 and agitates and sends the toner 6 therein. The toner hopper 10 is provided with a developing chamber 14 connected to the toner hopper 10 through an opening 12. The developing chamber 14 has a developing roller 16 for supplying the toner 6 to the photosensitive drum 4, and a developing roller 16. Supply roller 18 for supplying toner 6 from toner hopper 10
And a partitioning means 20 for blocking between the developing roller 16 and the toner hopper 10.

The developing chamber 14 having the developing roller 16 and the like and the toner hopper 10 constitute a so-called process cartridge. Here, reference numerals 22 and 24 indicate frames on the apparatus main body side, and reference numeral 26 indicates a toner layer uniformizing plate. A charger 28 and a cleaning blade 30 are provided around the photosensitive drum 4 upstream of the developing roller 16.

The partitioning means 20 is provided above the supply roller 18. The partitioning means 20 is a flat plate-like partition plate 32 which is integrally suspended from the upper surface of the developing chamber 14, and is formed between the lower end of the partition plate 32 and the supply roller 18. And a rotatable scraper mechanism 34 provided therebetween.

As shown in FIG. 2, the scraper mechanism 34 is provided with a rotating shaft 36 disposed substantially in parallel with the axis of the supply roller 18, and a plurality of the scraper mechanisms 34 provided at predetermined intervals in the longitudinal direction. And a disk-shaped inclined blade 38. Between the disc-shaped inclined blades 38,
The aforementioned toner passage area 38A is formed. The supply roller 18 is formed of a foam material, and the scraper mechanism 3
Reference numeral 4 denotes a state in which the inclined blade 38 slightly bites into the supply roller 18. Also, the scraper mechanism 34
Are driven to rotate in the same direction as the supply roller 18.

Next, the unifying action of the flow of the toner 6 will be described.

The toner hopper 1 is moved by the stirring and feeding operation of the mixer 8.
A part of the toner 6 sent from 0 to the developing chamber 14 flies toward the developing roller 16 without riding on the supply roller 18, but the upper part of the supply roller 18 in FIG. , And its upper part is blocked by a partition plate 32. As a result, the toner 6 floating in the upper space of the developing chamber 14 and flying toward the photosensitive drum 4 is dropped and incorporated into the original flow riding on the supply roller 18.

Further, the presence of the partitioning means 20 prevents the toner 6 from directly adhering to the developing roller 16 due to stagnation of the toner 6 even when the toner 6 is excessively supplied from the toner hopper 10.

Therefore, the toner 6 from the toner hopper 10
Are mostly supplied through the supply roller 18 to the developing roller 16.
Is supplied to the developing roller 1
The charged state of the toner 6 supplied to the toner 6 becomes uniform.

Further, since the partitioning means 20 in this embodiment has the scraper mechanism 34 having a partitioning function, the entry of the toner 6 into the supply roller 18 is prevented by the rotation operation of the scraper mechanism 34 and the entry is made. However, it is scraped out by the scraper mechanism 34. Therefore, the hardening of the supply roller 18 due to the intrusion of the toner 6 is prevented, and a good supply function to the developing roller 16 is maintained. Also, premature wear of the developing roller 16 due to hardening of the supply roller 18 is avoided.

The developing roller 16 and the toner hopper 10
The space between the toner hopper 10 and the supply roller 18 is kept as before, and the function of supplying the toner from the toner hopper 10 to the supply roller 18 is not hindered.

In the above-described embodiment, each component is shown in a specific shape. However, the present invention is not limited to this, and the design can be changed as appropriate within a range that satisfies the function of unifying the toner flow described above. .

[0030]

As described above, according to the present invention, the operation of the partitioning means can prevent the toner from directly reaching the developing roller from the toner hopper and unify the flow of the toner. Thus, it is possible to provide an unprecedented excellent image forming apparatus capable of improving print quality.

Further, the rotation is substantially parallel to the axis of the supply roller.
Shaft and a plurality of shafts are provided at intervals in the longitudinal direction.
Scraper machine composed of a tilted disk-shaped inclined blade
The structure makes it possible to prevent the supply roller from being hardened due to the entry of toner, so that the supply function to the developing roller due to the hardening can be prevented from being reduced, and the life of the developing roller can be extended by suppressing early wear of the developing roller. Can be.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a part of the scraper mechanism in FIG. 1;

FIG. 3 is a longitudinal sectional view of a main part showing a conventional example.

[Explanation of symbols]

 Reference Signs List 4 photosensitive drum 6 toner 8 mixer 10 toner hopper 16 developing roller 18 supply roller 20 partition means 32 partition plate 34 scraper mechanism 36 rotation axis 38 inclined blade

Claims (1)

(57) [Claims] A photosensitive drum having an electrostatic latent image formed on a surface thereof; a developing roller for supplying toner to the photosensitive drum;
An image forming apparatus comprising: a toner hopper having a mixer in which the toner is stored and sending the toner; and a supply roller for supplying the toner sent from the toner hopper to the developing roller. And a partitioning means for preventing toner sent from the toner hopper from directly reaching the developing roller, and the partitioning means is provided above the supply roller.
A partition plate, and the partition plate and the supply row.
Between the feed roller and the feed roller.
It consists of a scraper mechanism with multiple toner passage areas.
Form, the scraper mechanism, substantially parallel to the axis of the feed roller
Rotating shaft and a plurality of rotating shafts spaced apart in the longitudinal direction.
An image forming apparatus comprising: a disk-shaped inclined blade provided .