JPS5841511B2 - Roller Seizouhouhou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fixing roller which is used in an electrophotographic copying machine, a printing machine, a rocky shore, etc., and which heats and fixes a developed image on a copying material visualized with a developer. This is the first plastic surgery method.

Conventionally, a fixing device 1 using a heat roller and a pressure roller
In order to prevent unfixed toner (developer) from adhering to the roller surface and causing so-called offset, a method is used in which an anti-offset liquid such as silicone oil is applied to the surface of the heated roller or processing roller. .

Heat rollers generally have a built-in heater and a rubber layer made of silicone rubber around the outer circumference. When silicone oil is applied from the outside, the silicone oil penetrates through the rubber layer and changes the outer diameter. .

If the silicone oil is not uniformly applied to each rubber layer, the outer diameter will be non-uniform and there will be a difference in pressing force during fixing, causing problems such as uneven fixing and wrinkles in the copy material.

Also, do not apply anti-offset liquid to the roller surface.
By coating the outer surface of the roller that is in contact with the heat-fusible toner image surface on the copying material with RTV silicone rubber that has release properties, it is possible to prevent the offset of the toner image from the copying material and the wrapping of the copying material around the roller. There are known ways to prevent this.

However, the anti-offset performance of the RTv silicone rubber roller deteriorates over time, and in our experiments, the anti-offset ability of the rubber roller becomes impractical after being used for about 400 hours with the surface temperature of the rubber roller heated to 180°C. It dropped by 1 point until it didn't meet the criteria.

Furthermore, after fixing tens of thousands of sheets of copy paper for 200 hours, the outer diameter of the silicone rubber roller contracted and deformed by about 9% of its initial value, and the uniformity of fixing, paper feeding, etc. deteriorated significantly.

However, with conventional silicone rubber rollers, the rollers must be replaced after a certain period of time, and used rollers are discarded each time, which poses a major problem in terms of running costs and the effective use of raw materials. ing.

The present invention has been made in view of the above circumstances, and provides a method for shaping a fixing roller that can maintain a constant outer peripheral diameter for a long period of time and perform uniform fixing.

The present invention is characterized in that a roller made of a material that has the property of being swollen by an anti-offset liquid is placed in a mold means having a cylindrical inner wall surface, and the anti-offset liquid is permeated into the roller to uniformly swell the roller. The roller is swollen with anti-offset liquid and then sized to a finished size, which allows uniform fixing to be achieved during subsequent use. It can be easily restored to its original state and used.

General 1: If a silicone rubber roller is used for a long period of time, the pressure and heating of the silicone rubber (as described above) may cause uneven shrinkage, reduction in the diameter of the entire roller, deterioration of mold releasability, paper powder or toner powder, etc. However, uneven reduction of the roller diameter causes problems such as wrinkles on the copy material and uneven fixation, and deterioration of mold release properties and adhesion of paper powder and toner powder on the copy material. This causes the problem of winding around the rollers.

The main cause of deterioration in mold releasability is that silicone oil and low-molecular substances present in silicone rubber are reduced by evaporation due to heating or by being attached to copy paper and being carried away during paper passing.

Therefore, in order to restore the mold releasability, silicone oil may be injected into the roller again.

In general, with rubber rollers like the ones mentioned above, simply by soaking them in some kind of silicone oil for a long time, the silicone oil will penetrate into the rubber layer and the roller can be restored to a diameter close to its initial diameter. As a result, the diffusion progresses further into the interior, and the swelling of the silicone rubber progresses even further.

The degree of swelling can be adjusted by adjusting the silicone rubber material and silicone oil material, viscosity, impregnation, and diffusion time.

However, when the roller is immersed in a single silicone oil, the outer diameter of the roller becomes larger than necessary as shown by curve A in FIG. The roller must be removed from the anti-offset liquid at the point where the roller is removed, and accurate time management is required.

In the present invention, when manufacturing a fixing roller, it is finished to a predetermined size by the method shown in FIG.

In FIG. 2, 1 is a container for manufacturing a fixing roller, which is made of metal or oil-resistant resin and has a predetermined uniform inner diameter.

Container 1 has open ends at both ends;
It is sealed with a lid as shown.

It is preferable that the outer periphery of the lid 2 is knurled once as shown at 31 to prevent slipping, or that the outer periphery is polygonal.

4 is a sealing material that prevents oil from leaking to the outside, and is made of polyethylene, polyamide resin, fluororesin, or the like.

Reference numeral 5 denotes a used silicone rubber-coated roller with an uneven outer diameter and a predetermined diameter of 1. As shown in the figure, the roller is supported within the container so that the central axis of the roller is 1-fold in the center of the container. , the outer circumference of the roller is curved so that it does not touch the inner wall of the container.

7 is an offset prevention liquid. When the roller 5 is inserted into a container as shown in FIG. The roller swells until the outer surface of the rubber layer reaches the inner wall of the cylindrical container, and when the rubber layer reaches the inner wall of the cylindrical container, the roller stops swelling.

When the roller is immersed in the anti-offset liquid in the container according to the above embodiment, the outer diameter of the roller does not become larger than necessary after a certain period of time as shown by curve B in FIG. If the roller 5 is taken out of the container after a certain period of time 41 or more has elapsed after soaking, the roller will uniformly swell to approximately the same diameter as the inner diameter of the container, and both the outer diameter and mold releasability of the roller will be restored to the desired values. , it is possible to reuse it.

The anti-offset liquid includes dimethyl silicone oil and methylphenyl silicone oil with a viscosity of 50 cs to 500 cs.
Good results were obtained using the CS.

FIG. 3 shows an enlarged cross-sectional view of the main part of FIG. 2. Before swelling, the surface of the roller 5 may shrink unevenly due to long-term use, or the portion where the copying material separating member was in sliding contact may have been exposed for a long time. It has some bumps due to being scraped.

If you simply soak this roller in offset prevention liquid,
Since most swell in similar shapes, it is not possible to compensate for the shrinkage of non-uniform diameters, but when a roller is inserted into the container,
When a part of the roller swells until it reaches the inner wall of the container as shown in Figure 2, the anti-offset liquid moves as shown by the arrow in Figure 3, causing a thin offset between the inner wall and the part of the roller that has reached the inner wall. A film 9 of the preventive liquid is formed, and the swelling of the area is stopped.

In addition, the part that does not reach the inner wall continues to swell, and until it reaches the inner wall, as described above, by swelling the roller in the container, it is possible to correct the uneven diameter to a uniform diameter. The roller is a new roller, outer diameter, mold releasability,
Other fixing performances are also almost the same, and by repeating use and reproduction, it is possible to significantly reduce costs.

In addition, there is an offset prevention IE between the roller and the inner wall of the container.
Because a thin film of liquid is formed, the regenerated roller can be easily removed from the container.

FIG. 4 shows another embodiment.

Reference numeral 11 denotes a roller making container, which is a cylindrical pipe with a uniform inner diameter having open ends at both ends, and a roller 15 having a smaller diameter than a predetermined diameter is inserted into this pipe.

Reference numeral 10 denotes an anti-offset liquid tank, which is filled with an anti-offset liquid 17 such as silicone oil.

By immersing a large number of pipes 11 with rollers inserted into the tank, it is possible to produce one or more fixing rollers at one time.

FIG. 5 shows still another practical example, in which the roller making container 21 can be opened in the direction of the arrow and divided into two, and by inserting the roller 5 into the container, a roller of a predetermined size can be formed. can be created.

Also, since the anti-offset liquid permeates both ends of the roller from two directions, they tend to swell faster than other parts. As shown in Fig. 7, it is preferable to chamfer, but if the length of the rotisserie has a certain amount of margin during use, both ends of the roller will first touch the inner wall 1 of the container, as shown in Fig. 7, even without chamfering.
By utilizing this phenomenon, a closed space 11 filled with the anti-offset liquid may be formed, and then the opening and the lar can be allowed to swell until the anti-offset liquid in the closed space 11 reaches an equilibrium state.

In this case as well, the roller can be easily removed from the container.

In addition, in the example, the method was described as a method for regenerating a used roller, but when manufacturing a new roller, the amount of swelling of the roller relative to the content percentage of silicone oil is measured in advance, and the diameter is set to be smaller than the finished dimension. Of course, it is possible to use the above-mentioned container to make a roller with a desired uniform outer diameter, or it is also possible to infiltrate a desired amount (or a fixed amount) of anti-offset liquid into the roller. This is easy to do.

As described above, in the present invention, since the roller is swollen with an anti-offset liquid to have a predetermined size, it is possible to perform constant and stable fixing without causing uneven fixing.

In addition, a roller whose performance has deteriorated after being used for a long time can be recycled and used as a new roller, and the roller can be produced and manufactured at a low cost by effectively utilizing raw materials.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the change in the roller when it is immersed in offset prevention liquid, Figure 2 is a diagram showing the main part of the apparatus for manufacturing the roller of the present invention, and Figure 3 is an enlarged view of the main part of Figure 2. The sectional views, FIGS. 4 to 7, are views showing other embodiments of the present invention. 1... Container, 2... Lid, 5... Roller 7...
・Offset prevention liquid.

Claims (1)

[Claims] 1. A fixing roller, the surface of which is made of a silicone rubber layer that is swollen with silicone oil and has releasable properties, is disposed in a mold means having a cylindrical inner wall surface, and the inner wall surface of this mold means and the above-mentioned Filling the space between the roller and the silicone rubber layer surface with silicone oil, and causing the silicone rubber layer to swell with the silicone oil so that the peripheral surface of the silicone rubber layer reaches the inner wall surface of the mold means. A method for swelling a fixing roller in which the curved shape of the roller is shaped so as to correspond to the inner wall surface of the molding means.