JP2630259B2 - Image forming apparatus having toner scattering prevention function - 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 having a toner scattering preventing material used in an image forming apparatus such as a printer, a facsimile, a copying machine, etc. using an electrophotographic process.

[0002]

In the printer, a facsimile using the Prior Art Generally, electrophotographic processes, but regulates the copying thin layer in the developing device of the toner, dust toner generated in the contact portion and its surroundings, Fig. 2 As shown in (1), it may adhere to the charger 11, the charger wire 12 and the like, contaminate it, and cause poor charging.

For this reason, as a conventional measure for preventing the generation of powder smoke, the plate 13 is attached to the developing device side of the charging device 11 so as to prevent toner from entering the charging device 11 instead of directly preventing it by the developing device 14. Thus, the charger wire 12 is prevented from being contaminated.

[0004]

The above-mentioned conventional measures for preventing toner scattering do not directly take action at the location where the scattering occurs, so that toner scattering is not completely eliminated and toner scattering occurs. I have. Further, since there is a gap in the charger 11, toner flows from the gap, and therefore, the charger wire 12 is also contaminated, affecting charging performance and causing a defect that charging failure occurs.

SUMMARY OF THE INVENTION An object of the present invention is to provide a developing device in which toner scattering is prevented directly or at the vicinity of the toner scattering source or toner is forcibly collected to remove the contamination of the charger 11 and improve the charging performance. To provide.

[0006]

An image forming apparatus according to the present invention.
Is used to charge the photosensitive drum and the toner to the photosensitive drum.
And a developing device for supplying to the ram.
Thin layer regulation of toner on image roller with toner regulation blade
In an image forming apparatus having a developing process,
The toner regulating device disposed between the charging device and the developing device;
The contact point between the blade and the developing roller of the developing device and the periphery thereof
Metal defense that absorbs toner scattered from the surrounding area
And the metal defense is provided on the photosensitive drum.
When a voltage is applied that does not significantly affect the charged part,
The scattered toner is adsorbed .

[0007]

The metal defense according to the present invention is disposed between a developing device including a developing roller, a toner supply roller, and a toner regulating blade and a charger, and the metal defense is charged with a charge so that the metal defense takes charge. The toner scattered from the contact point of the blade and its surroundings is forcibly collected on the metal defense.

[0009]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention. The developing device having the toner scattering prevention material of the present invention,
As shown in FIG. 1, the basic configuration is the same as that of the conventional example shown in FIG. 2, and the developing device 6 has the developing roller 2 and the toner stored in the developing device 6 applied to the developing roller 2. The toner supply roller 3 includes a toner supply roller 3, a toner regulation blade 4 that regulates a thin toner layer on the development roller 2, and a blade holder 5 that mounts and holds the toner regulation blade 4. The toner supply roller 3 rotates in the direction of arrow P in the figure, and the developing roller 2 rotates in the direction of arrow S, so that the toner in the developing device is transferred from the toner supply roller 3 to the photosensitive drum 1 via the developing roller 2.
0 is supplied.

The toner regulating blade 4 is attached so as to be in pressure contact with the developing roller 2, and thins the toner supplied from the toner supply roller 3 onto the developing roller 2. In addition, the charger 7 for providing a charge for transfer has a charger wire 8 for discharging therein.

[0012]

[0013]

[0014]

[0015]

[0016]

The charger 7 charges the photosensitive drum 20 by applying a voltage of -850V. A voltage of −480 V is applied to the developing roller 2, and the charged toner adheres from the developing roller 2 to the electrostatic latent image on the photosensitive drum 10. At this time, the toner from the developing roller 2 is charged to -70 to -80 V, and the toner scattered from the developing roller 2 has the same voltage. The metal defense 30 is applied with a voltage for attracting the scattered toner and collecting the dust, thereby preventing the scattered toner from reaching the charger 7.

The metal defense 30 is arranged between the optical path of the writing light (dashed arrow in FIG. 1 ) from the exposure unit and the charger 7 in FIG.
Is better, and the optical path of the writing light and the developing roller 2
May be arranged between them. The voltage applied to the metal defense 30 is considered so as not to affect the charged portion of the photosensitive drum very much.

[0019] The embodiment of FIG. 1, the metal defense 30
Does not come into contact with the developing roller 2, so that the influence on the development can be reduced.

[0020]

As described above, according to the present invention is, Metarude
Defense, developing roller, toner supply roller, toner
A regulating blade, located between the developer and the charger
And make sure the metal defense is charged
Between the developing roller and the toner regulating blade
Forcibly collect scattered toner on metal defense
I do .

Therefore, there is an effect that the charger wire in the charger is not contaminated, defective charging is improved, and good charging performance is obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Toner scattering prevention material 2, 9 Developing roller 3 Toner supply roller 4, 10 Toner regulating blade 5 Blade holder 6, 14 Developing device 7, 11 Charging device 8, 12 Charger wire 13 Plate 30 Medal defense

Claims (1)

(57) [Claims] 1. A charging device for charging a photosensitive drum and toner.
And a developing device for supplying the photosensitive drum.
The toner on the developing roller to the toner regulating blade
Image forming apparatus with a development process that regulates thin layers
Wherein, disposed between the charging device and the developing device,
Contact point between the toner regulating blade and the developing roller of the developing unit
And a metal device that adsorbs toner scattered around
Metal defense, and the metal defense
A voltage that does not significantly affect the charged part of the optical drum
Being applied to adsorb the scattered toner.
Image forming device .