KR100275687B1 - Method of cleaning photosensing medium of image forming device - Google Patents

Abstract

PURPOSE: A method of cleaning a photosensing medium of an image forming device is provided to effectively remove a developer when developer is attached onto the photosensing medium. CONSTITUTION: The quantity of developer attached onto a photosensing medium is detected and it is judged if the quantity is above a predetermined reference value(S102). When there is an area where the quantity of developer attached onto the photosensing medium is less than the reference value, the area is additionally developed(S103). The developer attached onto the photosensing medium is removed to clean the photosensing medium(S105).

Description

Method for Cleaning Photosensitive Media of Image Forming Device

The present invention relates to a photosensitive medium cleaning method of an image forming apparatus for removing a developer adhering to a photosensitive medium of an image forming apparatus.

In general, the image forming apparatus is applied to a laser printer or a copying machine for a computer. These include dry using a powder toner and wet using a liquid toner mixed in a liquid carrier. The printing quality is good and the use of wet to prevent damage caused by harmful toner dust is gradually increased. That's the trend. In both of these methods, a desired image can be printed on paper by transferring a charged toner or liquid toner to a photosensitive medium on which a latent electrostatic image is formed, and then passing the paper through a rotating transfer roller which is in contact with the photosensitive medium. have.

1 is a schematic block diagram of a general image forming apparatus.

Referring to the drawings, the image forming apparatus includes a photosensitive belt 14 rotating in an endless track while being supported by a driving roller 11, a steering roller 12, a backup roller 13, and the like, and at least one developing device ( 17a, 17b, 17c, 17d and the transfer roller 25 are included. The surface of the photosensitive belt 14 is charged by the corona device 16, and the charging state of the surface of the photosensitive belt 14 is arranged in the vicinity of each of the developing devices 17a, 17b, 17c, and 17d. The potential is changed by scanning a laser beam from 18b, 18c, 18d. Beam scanning by the laser scanning devices 18a, 18b, 18c, and 18d forms an electrostatic latent image on the surface of the photosensitive belt.

The developing units 17a, 17b, 17c, and 17d can develop the colors of black, yellow, cyan, and magenta according to the color of the pigment, and also the laser scanning device 18a. 18b, 18c, and 18d also form an electrostatic latent image for that color. The developing units 17a, 17b, 17c, and 17d are filled with a liquid developer of a corresponding color. The drying roller 23 has a function of completely removing the liquid carrier from the toner image formed on the photosensitive belt 14. The toner image attached to the photosensitive belt 14 is transferred to the transfer roller 25 and can be transferred from the transfer roller 25 to the printing paper 27 by the surface energy difference. The cleaning apparatus 40 cleans residual toner remaining in the transfer roller 25 without being completely transferred in the transfer process. The eraser 15 performs a function of completely removing the charged state remaining on the photosensitive belt 14 so that a new electrostatic latent image can be formed.

In the residual developer cleaning operation of the conventional image forming apparatus as described above, when the developer amount of the developer attached to the photosensitive belt 14 by the developer 17a, 17b, 17c, 17d is less than an appropriate reference value, Transfer from the photosensitive belt 14 to the transfer roller 25 or transfer from the transfer roller 25 to the printing paper 27 becomes poor. In other words, if the developer remains on the photosensitive belt 14 or the transfer roller 25, it should be cleaned. However, when the amount of the adhesion is less than the reference value, it is difficult to effectively clean it. Therefore, when developing the developer for the next printing operation on the uncleaned photosensitive belt 14, the transfer from the photosensitive belt 14 to the transfer roller 25 becomes poor. Therefore, there is a problem that the quality of the image printed on the printing sheet 27 from the transfer roller 25 is inferior.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to improve the process of the photosensitive medium of the image forming apparatus so that the process can be effectively removed when the amount of the developer adhered to the photosensitive medium is small. It is to provide a cleaning method.

1 is a schematic configuration diagram of a conventional image forming apparatus.

2 is a flowchart illustrating an execution process of a photosensitive medium cleaning method of an image forming apparatus according to the present invention;

3 is a schematic configuration diagram of an image forming apparatus to which a photosensitive medium cleaning method of the image forming apparatus according to the present invention is applied;

<Description of the code | symbol about the principal part of drawing>

14. Photosensitive belts 17a, 17b, 17c, 17d.

18a, 18b, 18c, 18d. Laser injection device 25. Transfer roller

26. Compression roller 30. Detection means

40..Cleaning member

In order to achieve the above object, a photosensitive medium cleaning method of an image forming apparatus according to the present invention includes a photosensitive medium, a developer for attaching a developer to an electrostatic latent image formed on the photosensitive medium, and a transfer rotating in contact with the photosensitive medium. A method for cleaning a photosensitive medium of an image forming apparatus comprising a roller, the method comprising: detecting a deposition amount of a developer adhered on the photosensitive medium and determining whether the adhesion amount is greater than or equal to a reference value; If there is an area on the photosensitive medium in which the amount of developer is less than a reference value, further developing in the portion; And removing the developer attached to the photosensitive medium to clean the photosensitive medium.

Hereinafter, a method of cleaning a photosensitive medium of an image forming apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a flowchart illustrating an execution process of a photosensitive medium cleaning method of an image forming apparatus according to the present invention, and FIG. 3 is a schematic configuration diagram of an image forming apparatus to which the cleaning method of the image forming apparatus according to the present invention is applied.

2 and 3, the photosensitive medium cleaning method of the image forming apparatus according to the present invention is as follows. First, the photosensitive belt 14 rotates on the caterpillar while being supported by the driving roller 11, the backup roller 13, the steering roller 12, and the like. Laser scanning devices 18a, 18b, 18c, and 18d scan a laser beam on the photosensitive belt 14 to form an electrostatic latent image. Each of the color developing units 18a, 18b, 18c, and 18d provided in the image forming apparatus is developed by attaching a developer to the electrostatic latent image formed on the photosensitive medium 14 (S101). Thereafter, the surface potential detecting means 30 detects whether the deposition amount of the developer attached to the photosensitive medium 14 is less than a predetermined reference value appropriate for printing (S102). Here, the adhesion amount is expressed by the weight of the developer (μg / cm 2: mass / area) with respect to the unit area. If this amount is less than the reference value, the transfer of the developer to the transfer roller 25 and the sheet 27 becomes poor, resulting in poor print quality. The table shown below shows the transfer state when the amount of developer deposition is varied through experiments.

Developer adhesion amount (㎍ / ㎠) Image Density (ID) Warrior Status 38 X Bad 60 X Bad 84 0.65 Good 110 0.72 Good

According to Table 1, when the developer adhesion amount is 60 µg / cm 2 or less, the transfer state is poor. Therefore, in consideration of this, the reference value of the developer adhesion amount of a favorable transfer state is set to 80 microgram / cm <2>. The detecting means 30 detects whether or not the amount of the developer is attached to the reference value by using the difference in the surface potential according to the amount of the developer attached on the photosensitive belt 14. (S102)

If the amount of adhesion is not less than the reference value in the detection step (S102), the desired image is printed by passing the printing paper 27 between the transfer roller 25 and the compression roller 26 which rotates in contact with the photosensitive medium 14 and rotates. A normal print mode of printing on the sheet 27 is performed (S101).

If the deposition amount detected in the detection step S102 is less than the reference value, the developing units 17a, 17b, 17c, and 17d further develop a developer in a portion where the adhesion amount is less than the reference value (S103). Subsequently, the detecting means 30 detects whether the amount of the developer further developed in the additional developing step S103 is less than 80 µg / cm 2 (S104). When the deposition amount of the additionally developed developer detected in the detection step S104 is less than the reference value, the developing units 17a, 17b, 17c, and 17d further develop the developer in a portion where the adhesion amount is less than the reference value ( S103). Then, the detecting means 30 further detects whether the developer amount of the developed developer is less than the reference value (S104). That is, the additional development step (S103) is repeated until the adhesion amount is equal to or greater than the reference value. If the amount of adhesion detected in the detecting step S104 by this repetitive operation is equal to or greater than the reference value, the cleaning member 40 installed in the path after the detection means 30 removes the developer attached to the photosensitive belt 14. By cleaning the photosensitive belt 14 (S105). The cleaning member 40 may directly contact the photosensitive belt 14 to absorb or indirectly contact the developer to remove the developer. For example, the cleaning member 40 may be a roller which can rotate in contact with the photosensitive belt 14. In addition, the photosensitive belt 14 may be cleaned by removing the developer attached to the photosensitive belt 14 using the printing paper 27 without using the cleaning member 40 (S105). That is, the developer having an adhesion amount equal to or greater than the reference value is transferred from the photosensitive member 14 to the transfer roller 25 by the difference in surface energy between the photosensitive medium 14 and the transfer roller 25. Thus, the photosensitive medium 14 is cleaned. Then, the developer transferred to the transfer roller 25 is removed because it is transferred to the printing paper 27 passed between the transfer roller 25 and the compression roller 26. In addition, when the printing paper 27 passes between the photosensitive medium 14 and the transfer roller 25, the developer on the photosensitive medium 14 is transferred to the printing paper 27, thereby cleaning the photosensitive medium 14. After the cleaning step S105, it is determined whether to continue the job, and if there is an input print command, the job is continued, and if there is no input command, the job is terminated (S106).

As described above, according to the photosensitive medium cleaning method of the image forming apparatus according to the present invention, when a developer having a predetermined value less than a predetermined reference value is attached to the photosensitive medium, the photosensitive medium is removed after additional development in an amount suitable for discriminating and removing the developer. Can be cleaned cleanly, and the printing quality can be improved during the next printing operation.

Claims (4)

A photosensitive medium cleaning method of an image forming apparatus comprising: a photosensitive medium, a developer for attaching a developer to an electrostatic latent image formed on the photosensitive medium, and a transfer roller rotating in contact with the photosensitive medium Detecting the adhesion amount of the developer adhered on the photosensitive medium and determining whether the adhesion amount is greater than or equal to a reference value; If there is an area on the photosensitive medium in which the amount of developer is less than a reference value, further developing in the portion; And cleaning the photosensitive medium by removing the developer adhered to the photosensitive medium. The method of claim 1, And re-detecting the photosensitive medium after the additional developing step to re-determine whether an amount of the additionally developed portion is less than a reference value. The method of claim 1, wherein the cleaning step A photosensitive medium cleaning method of an image forming apparatus, characterized in that performed by printing paper which is moved in contact with a transfer roller which is brought into contact rotation with the photosensitive medium. The method of claim 1, wherein the cleaning step The photosensitive medium cleaning method of the image forming apparatus, characterized in that performed by a separate cleaning member in direct or indirect contact with the photosensitive medium.

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