JPH0455331Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field> This invention relates to a cleaning device for a fixing roller used in a copying machine or the like.

<Prior art and its drawbacks> Generally, a cleaning roller impregnated with a release agent (oil) is rolled into contact with the fixing roller of a copying machine, and the release agent is applied to the fixing roller as both rollers rotate. be done. On the other hand, if too much release agent is applied over the entire axial direction of the fixing roller, problems such as evaporation of the release agent may occur, so so-called oil-less systems that do not use this release agent at all are being tried. It's getting old. However, with this method,
When the fixed transfer paper is used as a document to be fed by an automatic paper feeder or the like, the following problems occur.

That is, as shown in FIG. 4, this type of paper feeding mechanism includes an upper roller 101 made of urethane rubber or the like and having a relatively large surface friction coefficient, a lower roller 102 made of rubber or the like and having a relatively small surface friction coefficient, and The paper feed auxiliary roller 103 pulls out the transfer paper M, the upper roller 101 secures paper feeding force for the transfer paper M, and the lower roller 10
2 is rotated in the opposite direction to the upper roller 101 to prevent multiple sheet feeding. However, the properties of the transfer paper M and the upper and lower rollers 101, 1
Strictly speaking, if there are two transfer papers M1 and M2 as shown in Figure 5A, due to foreign matter adhering to 02,
The first sheet of transfer paper M2 is dragged by the first sheet of transfer paper M1 toward the contact point between both rollers 101 and 102, as shown in FIG. 5B. Therefore, if these transfer sheets M1 and M2 have been fixed, the image P2 on the second sheet M2 will be rubbed by the lower roller 102 and adhere to this roller 102, and the image P2 will be transferred to the first or second sheet. The images P1 and P2 on the first sheet of transfer paper M1 and M2 are dirty, or the image P1 on the first sheet of transfer paper M1 is
and the back side of the second sheet of transfer paper M2 rub against each other.
The back side of the second transfer paper M2 is stained.

<Purpose of the invention> The purpose of the invention is to provide a fixing roller cleaning device that can eliminate the above-mentioned disadvantages and prevent the transfer paper from being stained by the paper feed roller.

<Structure and effect of the invention> This idea is structured as follows.

Consisting of an upper roller that rotates in the paper transport direction and a lower roller that rotates in the opposite direction to the upper roller, the paper feed roller feeds paper one sheet at a time into the copying machine body and presses against the paper on which toner has been transferred. a fixing roller that performs toner fixation; a porous roller body containing a release agent; and a cleaning roller that is comprised of a web attached to the outer peripheral surface of the roller body and rolls into contact with the fixing roller; and setting an aperture ratio of a region of the cleaning roller main body facing the paper feed roller to be larger than other regions.

With the above configuration, according to this invention, since the release agent applied from the cleaning roller to the fixing roller is large in the area facing the paper feed roller, the transfer paper after fixing is transferred to the fixing roller. When the transfer paper is fed by the transfer agent, the transfer paper is not rubbed due to the adhesion of the release agent, and staining of the transfer paper is prevented.
Furthermore, since the release agent is present only in a specific region of the fixing roller and is present in most other regions, the amount of evaporation can be reduced.

<Embodiment> FIGS. 1A and 1B are a top view and a side sectional view of a fixing roller cleaning device which is an embodiment of this invention.

In the figure, a pair of upper and lower fixing rollers 1 and 2 are composed of heat rollers, and a paper feed roller 10
1 and 102. A cleaning roller 6 supported by bearings 4 and 5 is in rolling contact with the upper fixing roller 1, and a shaft 7 is disposed along the axial direction of the fixing roller 1.
A plurality of peeling claws 8 are provided in sliding contact with the fixing roller 1 .

As shown in FIG. 2, the cleaning roller 6 includes a roller main body 10 containing a mold release agent 9 such as silicone oil inside, and a web 11 made of felt or the like attached to the outer peripheral surface of the roller main body 10.
A large number of holes 12 are formed on the outer peripheral surface of the roller body 10 over the entire area. The holes 12a in the area m (shaded area in FIG. 1) facing the paper feed rollers 101 and 102 in the roller body 10 are set to have a larger diameter than the holes 12b in other areas. A portion of the peeling claw 8 corresponding to the region m has been removed.

The rotation of the fixing rollers 1 and 2 causes the roller body 10 to
The release agent 9 inside flows out through the holes 12, 12a, and 12b and is applied to the fixing roller 1 via the web 11. Hole 12a in area m of the roller main body 10
Since the hole 12b has a larger diameter than the hole 12b in the other area, a large amount of the release agent 9 is applied to the fixing roller 1 in a portion corresponding to the area m. That is, after fixing, a large amount of release agent 9 is present on the transfer paper in the area corresponding to the area m.
is attached. Therefore, even when a plurality of sheets of transfer paper are fed by the paper feed rollers 101 and 102, the images on the transfer paper will not be rubbed off by the paper feed rollers 101 and 102, and the back side of the transfer paper will become dirty. is prevented. Furthermore, since most of the release agent 9 applied to the fixing roller 6 is concentrated in the portion corresponding to the area m, the problem of evaporation is also solved.

FIG. 3 shows a modification of the cleaning roller 6, in which the area m of the hole 12 of the roller body 10 is
In order to increase the aperture ratio of the hole 12a, the pitch of the holes 12a in this region m is made smaller than the pitch in other regions. In this case as well, the same effects as in the above embodiment can be achieved.

[Brief explanation of the drawing]

1A and 1B are respectively a top view and a side sectional view of a fixing roller cleaning device which is an embodiment of this invention, FIG. 2 is a sectional view showing the cleaning roller of the same device, and FIG. 3 is a sectional view of the cleaning roller of the same device. 4 is a sectional view showing a modified structure; FIG. 4 is a side sectional view of a paper feeding mechanism for feeding the transfer paper after fixing; FIG.
Figures A and B are explanatory views of the paper feeding mechanism during operation. 1, 2... Fixing roller, 101, 102... Paper feeding roller, 6... Cleaning roller, 9... Release agent, 10... Roller body, 11... Web, 1
2a, 12b...hole, m...area.

Claims (1)

[Scope of Utility Model Registration Claim] A paper feed roller that feeds paper one sheet at a time into the main body of a copying machine, consisting of an upper roller that rotates in the paper conveyance direction and a lower roller that rotates in the opposite direction to the upper roller; It consists of a fixing roller that fixes the toner by pressing against the paper onto which the toner has been transferred, a porous roller body containing a release agent, and a web attached to the outer circumferential surface of this roller body. What is claimed is: 1. A copying machine comprising: a cleaning roller that rolls into contact with the roller, and wherein an aperture ratio of a region of the cleaning roller body facing the paper feed roller is set larger than other regions.