KR19990020251A - Toner Layer Regulator of Developing Roller - Google Patents

Abstract

end. The technical field to which the invention described in the claims belongs.

The present invention relates to an image forming apparatus of an electrophotographic processor.

I. The technical problem that the invention is trying to solve.

SUMMARY OF THE INVENTION The present invention provides a toner layer regulating apparatus for a developing roller which is formed in a structure capable of forming a uniform toner layer on a developing roller by always applying a uniform pressing force to the developing roller even if time passes.

All. Summary of the Solution of the Invention.

The present invention provides a blade that is formed in the center of the pressing portion formed in the center so as to penetrate in the longitudinal direction, and a circular contact portion in contact with the developing roller at the lower side of the pressing portion is installed in place in the housing by a metal support. It is characterized by.

la. Important use of the invention.

The present invention relates to a toner layer regulating device for a developing roller.

Description

Toner Layer Regulator of Developing Roller

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus of an electrophotographic processor, and more particularly, to a toner layer regulating apparatus of a developing roller which constantly regulates a layer of toner applied to a developing roller.

Typically, one end is fixed in place in the housing to form a constant toner layer in the developing roller of the image forming apparatus, and the other end uses a blade having a predetermined shape in contact with the surface of the developing roller. As the blade, a blade (rigid blade) formed of an elastic blade or a metal rigid body is used.

1 is a block diagram of an image forming apparatus according to an embodiment of the prior art, Figure 2a is a main view showing a developing roller equipped with an elastic blade according to an embodiment of the prior art, Figure 2b A main part of a developing roller equipped with a metal rigid blade according to an embodiment is shown.

In the conventional configuration and operation of the image forming apparatus, as shown in FIG. 1, a photosensitive drum 101 rotating at a constant circumferential speed is installed in a housing 102 having a constant shape. Thereafter, in order to charge the photosensitive drum 101 at a high voltage, a charging roller 103 is mounted on one surface of the photosensitive drum 101. In addition, an exposure unit 104 for exposing a predetermined image to the photosensitive drum 101 charged by the charging roller 103 is formed on one side of the photosensitive drum 101. Thereafter, a developing roller 106 is mounted on one side of the photosensitive drum 101 to attach the toner 105 to a portion where the electrostatic latent image is formed by the exposure part 104 of the photosensitive drum 101. Thereafter, one side of the blade 107 is fixed to the housing 102 in order to form a constant toner 105 layer on the surface of the developing roller 106. The other side of the blade 107 is mounted in contact with the developing roller 106. Then, on the other side of the developing roller 106, a supply roller 108 for supplying the toner 105 to the developing roller 106 is provided. In addition, an agitator 109 is provided at one side of the feed roller 108 to stir the toner 105 and to supply the feed roller 108. The feed roller 108 and the stirrer 109 are installed in the toner loading portion 110 in the housing 102. Thereafter, a transfer roller 112 for transferring an image on the sheet of paper 111 is provided below the photosensitive drum 101.

As described above, the blade 107 is shown in FIGS. 2A and 2B, and the elastic blade deforms the elastic blade 107a by bringing the elastic blade 107a into surface contact in the direction opposite to the rotation of the developing roller 106. The amount of toner is constantly regulated by the pressing force caused by and the friction between the blade 107a and the toner. In addition, the rigid blade is to regulate the toner layer by bringing the metal rigid blade 107b, which is pressed by a pressure spring or the like, onto the developing roller 106 on the upper side of the frame.

However, in the case of using the elastic blade as described above, since the pressing force is determined by the elastic displacement of the elastic blade, the magnitude of the pressing force is changed by the difference in displacement according to the uniformity in the longitudinal direction of the blade and the positional accuracy of the blade. The pressure distribution in the longitudinal direction is also uneven, which makes it difficult to uniformly regulate the developer on the developing roller. In addition, in the case of a rigid blade, the hardness of the metal blade is high, so that the surface of the developing roller is scraped off while rubbing against the metal blade, and accordingly, the surface state of the developing roller changes over time. This change causes a problem of moving in the direction of increasing the developer feed amount on the developing roller and increasing the image density or uneven charging amount of the toner. In addition, in the case of a metal rigid blade, the developing roller and the blade must be contacted with a force for uniform contact, thereby increasing torque and severely causing jitter in an image.

In order to solve the above problems, an object of the present invention is a toner layer regulating apparatus of a developing roller which is formed in such a manner that a uniform toner layer on a developing roller can be formed by always applying a uniform pressing force to the developing roller even if time passes. To provide.

In order to achieve the above object, the present invention provides a photosensitive drum for forming an image, a charging roller for applying a high voltage to the photosensitive drum, an exposure unit for forming an electrostatic latent image on the photosensitive drum, and a photosensitive on which the electrostatic latent image is formed. An image forming apparatus of an electrophotographic processor in which a developing roller for supplying toner to a drum, a blade for constantly regulating the toner layer of the developing roller, and a supply roller for supplying toner to the developing roller are formed in a constant housing, The blade is characterized in that the pressing portion has a hole formed in the center so as to penetrate in the longitudinal direction, and a circular contact portion in contact with the developing roller is formed integrally under the pressing portion, and is installed in place in the housing by a metal support. .

1 is a block diagram of an image forming apparatus according to an embodiment of the prior art.

Figure 2a is a main part showing a developing roller equipped with an elastic blade according to an embodiment of the prior art.

Figure 2b is a main view showing a developing roller equipped with a metal rigid blade according to an embodiment of the prior art.

3 is a block diagram of an image forming apparatus according to an embodiment of the present invention.

Figure 4 is a perspective view showing the shape of a blade according to an embodiment of the present invention.

Figure 5 is a main view showing a state before the blade is mounted on the developing roller according to an embodiment of the present invention.

Figure 6 is a main view showing a state in which the blade is mounted on the developing roller according to an embodiment of the present invention.

Explanation of symbols for the main parts of the drawings

1: photosensitive drum 2: housing

3: charging roller 4: exposure part (LSU)

5: toner 6: developing roller

7: blade 8: feeding roller

9: stirrer 10: toner loading part

12: transfer roller 13: metal support

14: pressing portion 15: contact portion

16: hole

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used for the same components, even if displayed on different drawings. In describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

3 is a configuration diagram of an image forming apparatus according to an embodiment of the present invention, Figure 4 is a perspective view showing the shape of a blade according to an embodiment of the present invention.

5 is a main view showing a state before the blade is mounted on the developing roller according to an embodiment of the present invention, Figure 6 is a state in which the blade is mounted on the developing roller according to an embodiment of the present invention. That's one.

In the configuration of the image forming apparatus according to the present invention, as shown in Fig. 3, first, a photosensitive drum 1 rotating at a constant circumferential speed is provided in a housing 2 having a constant shape. Thereafter, a charging roller 3 is mounted on one surface of the photosensitive drum 1 to charge the photosensitive drum 1 at a high voltage. In addition, an exposure unit 4 for exposing a constant image to the photosensitive drum 1 charged by the charging roller 3 is formed on one side of the photosensitive drum 1. Thereafter, a developing roller 6 is mounted on one side of the photosensitive drum 1 to attach the toner 5 to a portion where the electrostatic latent image is formed by the exposure part 4 of the photosensitive drum 1. Thereafter, the blade 7 according to the present invention is fixed to the housing 2 so as to form a constant toner 5 layer on the surface of the developing roller 6.

As shown in FIG. 4, the blade 7 has a pressing part 14 having a hole 16 formed in the center thereof so as to penetrate in the longitudinal direction. Under the pressing portion 14, a circular contact portion 15 contacting the developing roller 6 is formed integrally with the pressing portion 14 and is installed in place in the housing by the metal support 13. . That is, the upper side of the pressing portion 14 is fixed to the metal support 13, the metal support 13 is fixed to the housing (2). The blade 7 is made of urethane-based conductive rubber.

Thereafter, a supply roller 8 for supplying the toner 5 to the developing roller 6 is provided on the other side of the developing roller 6. In addition, an agitator 9 is provided at one side of the feed roller 8 to stir the toner 5 to supply the feed roller 8. The feed roller 8 and the stirrer 9 are installed in the toner loading portion 10 in the housing 2. Thereafter, a transfer roller 12 for transferring an image on the sheet of paper 11 is provided below the photosensitive drum 1.

The operation relationship of the apparatus as described above will be described with reference to FIGS. 3 to 6.

First, when the blade 7 according to the present invention is installed in the housing by using the metal support 13, the pressing part 14 of the blade 7 bends outward with respect to the hole 16. Contact with the roller (6). That is, when the blade 7 is mounted in the housing, the pressing portion 14 is an elastic displacement having a constant pressing component to each other outward. This is because the conventional blade 7 is forced in only one direction, while the blade 7 according to the present invention generates vertical force by the left and right pressing portions 14, so that more precise control of the developer layer is possible.

Thereafter, the toner 5 loaded in the toner loading portion 10 is transferred to the feed roller 8 side by the stirrer 9. The transferred toner 5 is attached to the developing roller 6 by frictional charging of the supply roller 8 and the developing roller 6. Thereafter, the toner 5 attached to the developing roller 6 is regulated to a certain height on the developing roller by receiving the pressing force of the blade pressing portion. On the other hand, the photosensitive drum 1 is charged to a high voltage by the charging roller 3, the electrostatic latent image is formed by the exposure unit (4). Then, the toner 5 attached to the developing roller 6 is attached to the electrostatic latent image formed on the photosensitive drum 1, and the image is fed while the paper 11 is fed between the photosensitive drum 1 and the transfer roller 12. Is formed. Thereafter, the image formed on the paper is fixed by the fixing unit, not shown, and discharged to the discharge unit.

As described above, the blade having the pressurized component according to the embodiment of the present invention forms an accurate developer layer while maintaining a relatively wide contact width on the developing roller, thereby obtaining an image of very good quality.

Claims (3)

A photosensitive drum for forming an image, a charging roller for applying a high voltage to the photosensitive drum, an exposure portion for forming an electrostatic latent image on the photosensitive drum, a developing roller for supplying toner to the photosensitive drum having the electrostatic latent image formed thereon, and An image forming apparatus of an electrophotographic processor in which a blade for regulating a toner layer of a developing roller and a supply roller for supplying toner to the developing roller are formed in a constant housing, The blade is characterized in that the pressing portion is formed in the center to penetrate in the longitudinal direction, and a circular contact portion in contact with the developing roller is formed integrally below the pressing portion is installed in place in the housing by a metal support. Toner Layer Regulator of Developing Roller The method of claim 1, When the blade is mounted in the housing, the pressing portion toner layer regulating device of the developing roller, characterized in that the elastic displacement having a constant pressing component force to the outside of each other occurs. The method of claim 1, The blade is a toner layer regulating device of a developing roller, characterized in that the material is a urethane-based conductive rubber.