JPH0375773A - Toner fixing device - Google Patents

Abstract

PURPOSE:To sufficiently fix toner to a recording sheet by permitting a rubbing means to rub toner after a low-temperature heat roller temporarily fixes the toner at low temperature, making the toner to a high temperature with friction heat and comprehensively fixing it. CONSTITUTION:After the toner 2 supplied to a photosensitive drum 10 is transferred onto the recording sheet 1, a conveying belt 12 leads the sheet to the low-temperature heat roller 3, and the toner transferred onto the recording sheet 1 is temporarily fixed at a low temperature. A feed roller 13a leads the recording sheet 1 on with the toner 2 is temporarily fixed to the rubbing means 4, and a friction roller 41 rubs the toner 2 on the recording sheet 1. The toner 2 is made into a high temperature with friction heat and regularly fixed on the recording sheet 1. A cleaning roller 43 removes the toner 2 attaching to the outer periphery when it is rubbed, and the toner 2 is sufficiently fixed to the recording sheet 1 without soiling the recording sheet 1 and distorting a picture of the toner 2. After regularly fixing, the recording sheet 1 is ejected from the feed roller 13b.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a toner fixing device for fixing toner transferred onto recording paper in an electrophotographic apparatus or the like.

[Prior art and its problems] Conventionally, in electrophotographic devices, etc., toner is transferred from a photoreceptor drum or the like onto recording paper, and then the thus transferred toner is fixed on the recording paper. Ta.

Here, in order to fix the toner transferred onto the recording paper as described above, generally, the recording paper with the toner transferred thereto is guided between heating rollers, and the toner on the recording paper is fixed by this heating roller. It used heat and pressure to fix it on the recording paper.

However, in order to sufficiently fix the toner onto the recording paper using the heating roller, it is necessary to increase the fixing temperature of the heating roller or to slow down the fixing speed.

Here, in order to sufficiently fix the toner on the recording paper, if the fixing temperature of the heating roller is increased, a lot of power is required to heat the heating roller, which causes a problem of high running costs. Furthermore, when the fixing speed is slowed down, there is a problem in that the speed of the entire apparatus decreases and the time required for copying etc. increases.

In addition, in recent years, electrophotographic devices such as copying machines have become faster, and in this case, it is necessary to further increase the heating temperature of the heating roller to accelerate the toner fixing speed. Problems such as these existed as major problems.

[Problems to be Solved by the Invention] An object of the present invention is to solve the above-mentioned problems in a toner fixing device that fixes toner transferred onto recording paper.

That is, in order to fix the toner transferred onto the recording paper as described above, the present invention applies a large amount of electric power to the heating roller to raise its temperature, or slows down the fixing speed of the heating roller. It is an object of the present invention to provide a toner fixing device that can sufficiently fix toner on recording paper without causing any problems, and that can also cope with higher speeds of electrophotographic apparatuses.

[Means and effects for solving the problems] In order to solve the above-mentioned problems, the toner fixing device according to the present invention includes a low-temperature heating roller that temporarily attaches the toner transferred onto the recording paper to the recording paper at a low temperature. A friction means is provided for causing the toner tentatively deposited on the recording paper to be permanently fixed on the recording paper by rubbing the toner by the low-temperature heating roller.

In this toner fixing device, first, the toner transferred onto the recording paper is temporarily attached to the recording paper using the low-temperature heating roller, and then the toner temporarily attached to the recording paper is rubbed by a friction means. The toner temporarily adhered to the recording paper is permanently fixed by the frictional heat.

If the toner temporarily adhered in this way is permanently fixed by the frictional heat generated by the friction means, the power required for heating is only the low temperature heating roller that temporarily adheres the toner to the transfer paper, reducing power consumption. .

However, since the toner is temporarily attached to the transfer paper by a low-temperature heating roller and then permanently fixed to the recording paper by the friction of the friction means, when the toner is rubbed by the friction means, the toner image on the recording paper is disturbed. There is no such thing as occurring.

Here, there are various types of friction means as the above-mentioned friction means, but for example, a conveyance roller that conveys the transfer paper on which toner is temporarily attached on the back side of the transfer paper, and a conveyance roller that conveys the temporarily attached toner onto the recording paper. A friction roller that rubs with the paper is installed oppositely, and a difference is made between the circumferential speed of this conveying roller and the circumferential speed of the friction roller, and due to the difference in circumferential speed, the toner temporarily deposited on the recording paper is rubbed by the friction roller. Let them do it.

In addition, when the toner temporarily deposited on the recording paper is rubbed by the friction roller in this way, the outer peripheral surface of the friction roller is made smooth to reduce adhesion of toner and to avoid disturbing the toner image on the recording paper. In addition, it is preferable to use a friction roller with excellent thermal conductivity to improve the toner fixing property due to frictional heat. Use a material coated with a smooth and hard organic layer such as Teflon.

[Example] Hereinafter, an example of the present invention will be specifically described based on the accompanying drawings.

In this embodiment, as shown in FIG. 1, the toner (2) supplied to the photosensitive drum (10) is transferred onto the recording paper (1) via a charger for transfer/separation (11). After the transfer, the recording paper (1) is guided between a low-temperature heating roller (3) and <3> by a conveying belt (12).

And, by these low temperature heating rollers (3), (3),
The toner (2) transferred onto the recording paper (1) is heated at a low temperature to temporarily adhere to the recording paper (1), and then the toner (2) is transferred onto the recording paper (1).
) through the rollers (13), (13) and the friction means <
4).

Here, in this example, the friction means (
4), a friction roller (41) that rubs the toner (2) tentatively deposited on the recording paper (1) as described above on the recording paper (1), and a friction roller (41) that contacts the back side of the recording paper (1). A conveyance roller (42>) for conveying the recording paper (1>) is arranged vertically opposite to the conveyance roller (42>).

Further, as the friction roller (41), a metal roller whose outer peripheral surface is formed smoothly, has a small coefficient of friction, and has little adhesion of the toner (2) is used, while the conveyance roller (
42>, a silicone rubber roller with a large friction coefficient is used to convey the recording paper (1), and the circumferential speed of the friction roller (41) is adjusted to the conveyance roller (42).
) is set to be faster than the circumferential speed.

Then, the recording paper (1> on which the toner (2) has been temporarily attached as described above is transferred to the conveyance roller (42) and the friction roller (41).
), the conveyor roller with a large friction coefficient (
The recording paper (1) is transported by the transport roller (42), and the recording paper (1) is transported by the transport roller (42) in this way.
While the toner (1) is being conveyed, the friction roller (41) whose circumferential speed is faster than the conveyance roller (42) frictionally removes the toner (2) temporarily deposited on the recording paper (1) as described above. death,
The toner (2) is permanently fixed onto the recording paper (1) by the frictional heat.

In addition, in this embodiment, when the toner (2) temporarily deposited on the recording paper (1) is rubbed by the friction roller (41) as described above, the rubbed toner (2)
Even if a part of the toner adheres to the outer peripheral surface of the friction roller (41), the attached toner (2) may cause the recording paper (1>
In order to prevent the friction roller (
A cleaning roller (43) is provided so as to be in contact with the outer circumferential surface of the friction roller (41), and the cleaning roller (43) removes toner (43) attached to the outer circumferential surface of the friction roller (41).
2) is removed.

Then, while the recording paper (1) is transported by the transport roller (42>) as described above, the toner (2) tentatively deposited on the recording paper (1) is rubbed by the friction roller (41>). After fixing the recording paper (1) onto the recording paper (1), the recording paper (1) is conveyed by feed rollers (13>, (13)) and ejected.

In this embodiment, as described above, the friction roller (4) is used as the friction means (4) for permanently fixing the toner (2) temporarily deposited on the recording paper (1).
1> and a conveyance roller (42>) are arranged vertically opposite each other, and the circumferential speed of the friction roller (41) is set higher than the circumferential speed of the conveyance roller (42), so that recording is performed using the friction roller (41) with a high circumferential speed. The toner (2) tentatively deposited on the paper (1) is rubbed, but conversely, the peripheral speed of the friction roller (41> is made slower than the peripheral speed of the conveyance roller (42>), and the toner (2) temporarily deposited on the paper (1) is )
The toner (2) tentatively deposited on the friction roller (4)
1), it is also possible to carry out permanent fixation on the recording paper (1) by rubbing.

Furthermore, it is also possible to use other friction means (4) as long as it can rub the toner (2) temporarily attached to the recording paper (1) and permanently fix it on the recording paper (1). It is.

[Effects of the Invention] As detailed above, in the toner fixing device according to the present invention, after the toner transferred onto the recording paper is temporarily attached to the recording paper by the low-temperature heating roller, the toner is fixed onto the recording paper in this way. Since the temporarily adhered toner is rubbed by a friction means and the temporarily adhered toner is permanently fixed on the recording paper using the frictional heat, the electric power required for heating is used by the low-temperature heating roller that temporarily adheres the toner to the transfer paper. This reduces power consumption.

Further, in the toner fixing device according to the present invention, after the toner is temporarily attached to the transfer paper by the low-temperature heating roller,
Since the toner is permanently fixed on the recording paper by the friction caused by the friction means, when the toner is rubbed by the friction means,
There was no disturbance in the toner image on the recording paper.

As a result, when using the toner fixing device according to the present invention, in order to sufficiently fix the toner on the recording paper, it is necessary to raise the temperature of the heating roller to a high temperature or slow down the fixing speed, as in the past. There is no need to do this, reducing running costs, reducing the time required for copying, etc., and making it possible to respond to faster speeds of electrophotographic equipment.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing how a toner fixing device according to an embodiment of the present invention is used.

Claims (1)

[Claims] 1. A low-temperature heating roller that temporarily adheres the toner transferred onto the recording paper to the recording paper at a low temperature, and a friction means that causes the toner temporarily adhered to the recording paper to be permanently fixed on the recording paper by rubbing the toner with the low-temperature heating roller. A toner fixing device comprising: