KR20000051026A - Transfer roller cleaning apparatus for printer - Google Patents

Abstract

PURPOSE: An apparatus for cleaning a transfer roller for a printer is provided to remove residual impurities except a toner image without damaging the toner image by a second cleaning roller which rotates in contact with the transfer roller alternatively. CONSTITUTION: An apparatus for cleaning a transfer roller for a printer includes a first cleaning roller(22) for cleaning a surface of the transfer roller after transferring a toner image to a printing paper, a second cleaning roller(24) rotatably mounted in an alternative contact with a surface of the transfer roller before the transfer roller contacts the printing paper, and a moving element(32,34,36) for making the second cleaning roller alternatively contacted or separated from the transfer roller, wherein the cleaning is performed for front and rear end parts of the toner image except the toner image transferred by the transfer roller.

Description

Transfer roller cleaning apparatus for printer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer roller cleaning apparatus for a printing press, and more particularly, to a transfer roller cleaning apparatus for a printing press for cleaning a surface of a transfer roller which transfers a toner image formed on a photosensitive belt to a printing paper.

In general, a printing machine includes a dry type using only a solid toner as a developer and a wet type using a developer in which a solid toner and a liquid carrier are mixed. By the way, in the case of dry, wet is mainly used in recent years because of the fact that toner dust used as a developer is harmful to the human body, and an example of such a wet printing machine is shown in FIG. 1.

Referring to FIG. 1, a wet printing machine prints a photosensitive belt 10, which is a photosensitive medium that is supported by a plurality of support rollers 11 and travels on an orbit, and an image formed in an electrostatic latent image region of the photosensitive belt 10. A transfer roller 15 for transferring to the paper P is provided.

The surface of the photosensitive belt 10 is maintained at a potential level of a predetermined level by the charger 12, and the potential is changed by the light scanned by the laser scanning unit 13 provided adjacent to each of the developing devices 14. An electrostatic latent image is formed. After the developer 14 is attached to the electrostatic latent image region formed as described above, the toner is filmed to form a toner image, and most of the remaining carriers are squeezed out. do.

On the other hand, the toner image formed on the photosensitive belt 10 as described above is printed on the transfer roller 15 by the difference in surface energy, and then passes through the transfer roller 15 and the fixing roller 16. It is moved to (P) and finally printed. Then, foreign matters such as toner residue which are slightly left in the transfer roller 15 without being transferred to the printing paper P are cleaned and removed by the first cleaning roller 17 which is rotated in contact with the transfer roller 15. .

In the above configuration, however, the transfer roller transfers not only the toner image formed on the photosensitive belt, but also foreign matters that may occur at the front end and the rear end of the toner image. Therefore, the foreign matter thus transferred is transferred to the printing paper together with the toner image, thereby contaminating the printing paper.

The present invention was devised to solve the above problems, and an object thereof is to provide a transfer roller cleaning device for a printing machine having an improved structure so that foreign matters transferred from the photosensitive belt to the transfer roller can be removed before being transferred to the printing paper. .

1 is a schematic diagram showing a typical wet printing machine.

Figure 2 is a schematic diagram showing a part of a printing machine employing a transfer roller cleaning device according to an embodiment of the present invention.

Figure 3 is a schematic configuration diagram for explaining the operation of the transfer roller cleaning apparatus according to an embodiment of the present invention.

<Description of Symbols for Major Parts of Drawings>

10. Photosensitive belt 11. Support roller

15. Transfer Roller 16. Fixing Roller

22. First cleaning roller 24. Second cleaning roller

32. Rotating member 34. Cam

36.Spring

The transfer roller cleaning apparatus for a printing press according to the present invention for achieving the above object is for cleaning the surface of the transfer roller for transferring the toner image formed on the photosensitive medium and finally transferring the transfer paper to the printing paper passing between the fixing roller, A transfer roller cleaning apparatus for a printing machine comprising a first cleaning roller for cleaning the surface of the transfer roller after transferring a toner image onto the printing paper, the contact roller being selectively brought into contact with the surface before contacting the printing paper of the transfer roller. A second cleaning roller which is possibly installed; And moving means for selectively contacting and separating the second cleaning roller from the transfer roller, and partially cleaning only the line / rear portion of the toner image other than the toner image transferred to the transfer roller. It is done.

Hereinafter, a transfer roller cleaning apparatus for a printing press according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIG. 2, the transfer roller cleaning apparatus according to the present embodiment includes a first cleaning roller 22 installed in the transfer roller 15 so as to be in contact rotation, and a material in which the transfer roller 15 is selectively rotated in contact with the transfer roller 15. And a moving means for moving the second cleaning roller 24 and the second cleaning roller 24 in position. Here, the same reference numerals are given to the same components as those in the drawing shown in FIG. 1.

The first cleaning roller 22 represents the same member as the first cleaning roller indicated by reference numeral 17 in FIG. 1. The second cleaning roller 24 is provided to be in contact with and spaced apart from the transfer roller 15. Specifically, as shown in FIG. 2, the contacting position of contact rotation of the transfer roller 15 and the spaced apart position of the transfer roller 15 as shown in FIG. 3 are movable. In addition, the second cleaning roller 24 is positioned so as to be capable of contact rotation on the surface of the transfer roller 15 before contacting the printing paper P. FIG. That is, the second cleaning roller 24 is positioned so as to face the printing paper P before passing between the transfer roller 15 and the fixing roller 16 as shown.

The moving means may include a pivot member 32 supporting the second cleaning roller 24, a cam 34 installed on the pivot member 32 so as to be in contact with the pivot member 32, and the pivot member 34 in the spaced apart position. It is provided with a spring 36 for pressing.

The rotating member 32 rotatably supports the second cleaning roller 24 at one end thereof, and the other end thereof is hinged to a predetermined hinge point H so as to be rotatable at a predetermined angle. Specifically, the rotation member 32 is installed to selectively move the second cleaning roller 24 to the contact position and the spaced apart position while being rotated about the hinge point (H). When the cam 34 rotates, the cam 34 is pushed by the cam 34 to the contact position and pressed by the spring 36 to the spaced apart position. Here, one end of the spring 36 is connected to the rotation member 32, the other end may be fixed to a predetermined support (not shown).

The operation of the transfer roller cleaning apparatus for a printing press according to the present embodiment having the above configuration will be described with reference to FIGS. 2 and 3.

First, in the printing operation, the toner image T is formed in the electrostatic latent image region of the photosensitive belt 10. The toner image T is moved together with the photosensitive belt 10 that is driven and transferred to the transfer roller 15 by the difference in surface energy. At this time, portions other than the toner image T, that is, the line / rear portion of the toner image T may be contaminated by foreign matter such as toner dust, and in this case, the foreign matter on the photosensitive belt 10 may also be transferred. Transferred to the roller 15 to contaminate its surface. At this time, as shown in FIG. 2, the cam 34 is rotated immediately after the toner image T1 upstream passes, and the second cleaning roller 24 is brought into contact with the transfer roller 15. As shown in FIG. The second cleaning roller 24 in contact as described above is driven by scraping and removing foreign substances, etc. stuck to the surface of the transfer roller 15 while being driven. Here, when the second cleaning roller 24 arrives at the point where the toner image T2 downstream of the photosensitive belt 10 is transferred to the transfer roller 15 and faces the second cleaning roller 24. Until it is maintained in contact with the transfer roller 15. Then, when the cam 34 is rotated just before the toner image T2 passes, the rotating member 32 is moved by the spring 36 as shown in FIG. 3 to form the second cleaning roller 24. Is located at the spaced position. Therefore, the second cleaning roller 24 is capable of suppressing contamination of the printing paper P by removing only foreign substances remaining at the front / rear portions of the toner image T without damaging the toner image T. do.

Here, the control of the contact and separation time of the second cleaning roller 24 with respect to the transfer roller 15 may be performed by a predetermined control unit (not shown) using position information of the toner image T formed on the photosensitive belt 10. After inputting, the time taken for the toner image T to reach the contact portion between the transfer roller 15 and the second cleaning roller 24 in consideration of the travel time of the photosensitive belt 10 is calculated. It is possible by appropriately driving 35).

On the other hand, after the toner image T1 is transferred onto the printing paper P, the first cleaning roller 22 cleans and almost removes toner dust remaining in a small amount on the surface of the transfer roller 15. Contamination of the toner image T2 transferred to the transfer roller 15 can be suppressed.

According to the transfer roller cleaning apparatus according to the embodiment of the present invention as described above, by providing a second cleaning roller that is selectively contact rotated to the transfer roller, foreign matter remaining in portions other than the toner image without damaging the toner image Only the bay can be removed.

Therefore, there is an advantage that the quality of printing can be improved by suppressing the contamination of the printing paper.

Claims (2)

A method for cleaning a surface of a transfer roller which transfers a toner image formed on the photosensitive medium to a final transfer paper to a printing paper passing through the fixing roller, and which cleans the surface of the transfer roller after transferring the toner image to the printing paper. In the transfer roller cleaning apparatus for a printing machine comprising one cleaning roller, A second cleaning roller installed on the surface of the transfer roller before contact with the printing paper so as to be selectively rotated; And moving means for selectively contacting and separating the second cleaning roller from the transfer roller. A cleaning roller cleaning device for a printing machine, characterized in that only the front / rear portions of the toner image are partially cleaned except for the toner image transferred to the transfer roller. The method of claim 1, wherein the moving means, A rotating member for supporting the second cleaning roller to be movable between a contact position in contact with the transfer roller and a spaced apart position; A cam installed on the rotating member so as to be rotatable, and rotating the rotating member; And And a spring for urging the pivot member to the spaced position.