JPH0213308B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an improvement of a roller fixing device used for fixing a toner image to a recording sheet in a recording device such as an electrophotographic copying machine. A support such as a recording paper attached to the surface is passed between a pair of pressure rollers to which an anti-offset liquid is applied to the roller on the side to which the toner image is attached, and the toner image is supported by applying pressure or further heating. The present invention relates to an improvement of a roller fixing device for fixing to a body.

[Prior art]

In general, in the roller fixing device described above, at least one of the pair of pressure rollers, in most cases, has a toner image attached to it, in order to make the device lightweight and compact, and to stabilize and speed up fixing. The side rollers are heated by a heat source provided inside or outside the rollers. That is, the most popular type is one in which the toner image is fixed by heating and pressure. The roller on the side to which the toner image is attached is particularly prone to offset of the toner from the support, and because the offset toner tends to wrap around the support, an anti-offset liquid such as silicone oil (hereinafter referred to as oil) is applied to the roller. ) is applied to the surface. However, if too much oil is applied, the support becomes contaminated with oil, which makes it difficult to write on the support later with pencil or ink, and the amount of oil consumed increases, making it uneconomical. It's hot. Therefore, many means have been employed to apply a thin layer of oil uniformly to the surface of the roller. As such oil applying means, those shown in FIGS. 1 to 4 are known.

In FIGS. 1 to 4, reference numerals 1 and 2 are a pair of fixing rollers that rotate in the direction of the arrow and come into pressure contact with each other, and roller 2 is provided with a heat source 3 such as a halogen tube heater or a resistance heating element inside. This roller presses the side of the support on which the toner image is attached. 4 is an oil tank, 5 is an oil transfer section, and 6 is an oil tank.
7 and 8 are scraping members and wiping members for removing excess oil and dirt adhering to the roller 2; 9 is an oil-impregnated felt, sponge, etc.; This is an oil applying member.

The oil application means shown in FIGS. 1 to 3 are as follows:
Compared to the oil applying means shown in Fig. 4, it seems to have the advantage of being able to apply oil to the roller 2 indefinitely as long as the oil tank 1 is replenished with oil, but this makes the device complicated and large. Moreover, in practice, dirt such as toner and paper powder adheres to the oil application section 6, causing clogging, and the oil cannot be applied uniformly in a relatively short period of time. The benefits are rarely realized. In this respect, the oil applying means shown in FIG. 4 is designed so that the oil applying member 9 can be fixed to the holding frame 10 by rollers so that it can be easily replaced on the premise that the oil applying member 9 runs out of oil and becomes dirty. Since the device is configured to be installed by inserting it from the side into the mounting rail 12 provided on the top lid 11 of the device frame, the device is simple and compact, and the oil applying member 9 can be replaced together with the holding frame 10 as needed. This has the advantage that oil can always be uniformly applied. However, even with the oil applying means shown in FIG. 4, even though the oil applying member 9 is still sufficiently impregnated with oil, it may be necessary to replace it due to dirt, or the oil applying member 9 may be contaminated with oil before being replaced. There is a problem that when the roller 2 is replaced, the dirt remains on the surface of the roller 2 together with the oil and contaminates the support, and the oil applying member 9 becomes dirty quickly after the replacement.
There is also the problem that the dirty oil application member 9 cannot be easily reused.

[Purpose of the invention]

The present invention has been made in order to solve the problems in the conventional oil applying means as described above, and the first object of the present invention is to provide a simple and compact device as shown in FIG. A second object of the present invention is to provide a roller fixing device that solves the problem of replacing the oil applying member of the oil applying means. To provide a roller fixing device capable of uniformly applying oil until almost no oil is left.

[Structure of the invention]

In the present invention, a support with a toner image adhered to its surface is passed between a pair of pressure rollers to which an anti-offset liquid is applied to the roller on the side to which the toner image is attached, and the toner is removed by applying pressure or further heating. In a device for fixing an image to a support, an anti-offset liquid applying member is held by a holding frame having a scraping blade at one end, and the holding frame is fitted onto a mounting rail of a fixing device frame to prevent the anti-offset liquid applying member from fixing the image. An anti-offset liquid is applied to the roller, and the surface of the roller is rubbed parallel to the axis by the scraping blade when the holding frame is attached to and detached from the mounting rail. A roller fixing device characterized by the above structure, which achieves the first object described above, and further includes a cleaning member for cleaning the roller before applying oil to the roller, which is also held in the holding frame. In this specific embodiment of the present invention, the above-mentioned second object is also achieved.

〔Example〕

The present invention will be explained below based on the embodiments shown in FIGS. 5 to 13.

FIG. 5 is a perspective view of essential parts showing an example of the roller fixing device of the present invention, FIG. 6 is a partial front view, FIG. 7 is a partial side view as seen from the scraping blade side, and FIGS. 8 to 10 are Partial front views showing examples of the shape of the scraping tip of the scraping blade, FIGS. 11 and 12
FIG. 13 is a side view of essential parts showing another example of the roller fixing device of the present invention, and FIG. 13 is a sectional view showing another example of the oil applying member.

In these figures, the same reference numerals as in FIGS. 1 to 4 indicate the same functional members, but the holding frame 10
The roller not only holds the oil applying member 9 but also holds a cleaning member 13 for cleaning the surface of the roller 2 before the oil applying member 9 applies oil to the roller 2, and further has a scraping blade 14 at one end. In this respect, the holding frame 10 in FIG.
It differs from

The scraping blade 14 scrapes the surface of the roller 2 in the axial direction when the holding frame 10 is attached to and detached from the mounting rail 12 to remove residual adhesion from the cleaning member 13 and the oil applying member 9 to the surface of the roller 2. It removes dirt and oil from
Preferably, the material is made of a material having excellent elasticity and heat resistance, such as silicone rubber, fluorocarbon rubber, tetrafluorocarbon resin, or perfluoroalkoxyethylene resin. The scraping tip of the scraping blade 14 has an appropriate shape as shown in FIGS. 7 to 10 to ensure effective scraping.

The cleaning member 13 shown in FIG. 5, FIG. 7, and FIG. 12 is a rod-shaped member made of a material such as felt or sponge that can easily wipe away dirt and oil, and the one shown in FIG. A cleaning layer 1 made of felt, sponge, etc. is placed around the outer periphery of a roller core 13a that is pivotally supported on the end surface of the holding frame 10.
3b is provided in the form of a roller. The cleaning layer 13b of the rod-shaped cleaning member 13 or the roller-shaped cleaning member 13 is made of felt made of aromatic polyamide fiber (for example, Nomex felt manufactured by DuPont), which has heat resistance, wipeability, and
It is preferably used from the viewpoint of durability, and it is preferable to impregnate it with an appropriate amount of oil to further improve the wiping property. By providing such a cleaning member 13 on the holding frame 10 so as to clean the surface of the roller 2 before the oil applying member 9 applies oil, the oil applying member 9 is free from oil due to dirt. The application function is not impaired, and the accumulation of dirt on the cleaning member 13 is prevented by the oil application part 6 of the oil application means.
Since the accumulation of dirt and dirt on the oil applying member 9 does not impair the cleaning function to the extent that it impairs the oil applying function, it is possible to uniformly apply oil to the roller 2 until the oil held by the oil applying member 9 is almost completely exhausted. Therefore, it is possible to obtain the effect that the replacement period of the holding frame 10 is extended. However, in the present invention, the holding frame 10
The cleaning member 13 is not limited to the example in which the cleaning member 13 is provided.

The oil applying member 9 shown in FIGS. 5 to 7 and 11 is rod-shaped like that in FIG. 4, but the oil applying member 9 shown in FIG. 12 is a roller-shaped cleaning member 13. It is roller-shaped like . That is, the oil applying member 9 in FIG.
In this example, an oil-impregnated layer 9b made of oil-impregnated felt, sponge, etc. is provided on the outer periphery of a roller core 9a that is pivotally supported on the end face of a holding frame 10. Instead of this roller-shaped oil application member 9, one as shown in FIG. 13 may also be used. The oil applying member 9 in FIG. 13 is different from the oil applying member 9 in FIG.
Instead of the roller core 9a, a drum-shaped roller core 9a' is used, which has an oil supply port on the end face, can store oil inside, and has an oil seepage hole in the peripheral wall. 9
b is an oil-impregnated layer as in FIG. 12. In addition, if an oil exudation layer having higher oil passage resistance than the internal oil-impregnated member is further provided on the surface of the rod-shaped or roller-shaped oil applying member 9 that comes into contact with the roller 2,
Even if the internal oil-impregnated member is impregnated with a large amount of oil, or even if the contact pressure of the oil-applying member 9 against the roller 2 is increased, it is possible to more stably and uniformly apply oil to the roller 2 in a thin layer. This effect can be obtained. However, it goes without saying that the present invention is not limited thereto.

〔Effect of the invention〕

The roller fixing device of the present invention as described above has a simple and compact structure, and prevents dirt from remaining on the fixing roller and causing damage when replacing the oil application member or cleaning member. Furthermore, excellent effects such as being able to uniformly apply oil to the fixing roller until the oil in the oil applying member is almost completely exhausted can be obtained. Further, in the case where the cleaning member is also held in the holding frame, it is relatively easy to remove dirt from the cleaning member and recycle it, so that it is easy to reuse it.

[Brief explanation of drawings]

1 to 4 are side views of essential parts showing an example of a conventional roller fixing device, FIG. 5 is a perspective view of essential parts showing an example of the roller fixing device of the present invention, and FIG. 6 is a partial front view, and FIG. FIG. 7 is a partial side view seen from the scraping blade side; FIGS. 8 to 10 are partial front views showing examples of the shape of the scraping tip of the scraping blade;
11 and 12 are side views of essential parts showing another example of the roller fixing device of the present invention, and FIG. 13 is a sectional view showing another example of the oil applying member. 1, 2...Fixing roller, 3...Heat source, 4...
Oil tank, 5... Oil transfer part, 6... Oil application part, 7... Scraping member, 8... Wiping member, 9... Oil applying member, 9a, 9'a...
Roller core, 9b...Oil impregnated layer, 10...Holding frame, 11...Device frame upper lid, 12...Mounting rail, 13...Cleaning member, 13a...Roller core, 13b...Cleaning layer, 14... scraping blade.

Claims (1)

[Scope of Claims] 1. A support with a toner image attached to its surface is passed between a pair of pressure rollers to which an anti-offset liquid is applied to the roller on the side to which the toner image is attached, and the support is pressurized or further heated. In the device for fixing the toner image on the support by the above method, the anti-offset liquid application member is held in a holding frame having a scraping blade at one end, and the holding frame is fitted onto the mounting rail of the fixing device frame to apply the anti-offset liquid. The anti-offset liquid is applied to the roller by the applying member, and the surface of the roller is rubbed parallel to the axis by the scraping blade when the holding frame is attached to and removed from the mounting rail. A roller fixing device characterized by comprising: 2. The roller fixing device according to claim 1, wherein the holding frame also holds a cleaning member for cleaning the surface of the roller before the anti-offset liquid applying member applies the anti-offset liquid to the roller. 3. The roller fixing device according to claim 1 or 2, wherein the scraping blade of the holding frame is made of silicone rubber. 4. Claim 1 or 2, wherein the scraping blade of the holding frame is made of fluorocarbon rubber.
The roller fixing device described in Section 1. 5. The roller fixing device according to claim 1 or 2, wherein the scraping blade of the holding frame is made of tetrafluorocarbon resin. 6. The roller fixing device according to claim 1 or 2, wherein the scraping blade of the holding frame is made of perfluoroalkoxyethylene resin.