JPH05188814A - Method for cleaning rotating body for fixation - Google Patents

Abstract

PURPOSE:To miniaturize a fixing device by obviating a cleaning member such as a cleaning pad disposed by being made to press-contact with a roller for fixation. CONSTITUTION:A fixing roller 1 is rotated in a direction shown by an arrow C by a fixing knob. Then, a cleaning sheet 10 is made to enter the nip part of the roller 1 and a pressure roller 2 and carried in a direction shown by an arrow D. Thus, depositions retained at a separation pawl 4, a thermoswitch 6 and the abutting part (hashed part) of a thermistor 5 is peeled and moved in a direction shown by an arrow E. Besides, it is moved to the sheet 10 and eliminated at the nip part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning method for a fixing rotary member of an image forming apparatus such as a copying machine or a laser printer.

[0002]

2. Description of the Related Art A fixing device fixes an unfixed developer image (hereinafter referred to as a toner image) carried on a transfer paper as a recording material as a permanent image on the transfer paper. As such an apparatus, conventionally, a heat roller type has been widely used in which a toner image on a transfer sheet is heated and pressed through a roller to melt and fix the toner image on the transfer sheet. This heat roller type fixing device includes a pair of fixing rollers including a heating roller having a heat source such as a halogen lamp and rotating in a fixed direction, and a pressure roller rotating in pressure contact with the heating roller. The toner image is fixed on the transfer paper by passing the transfer paper carrying the toner image between the fixing rollers. In addition, various types of fixing methods such as pressure fixing and the like are used in which a transfer sheet is nipped and conveyed using a pair of fixing rotators and fixing is performed at the nip portion. Further, as the material of the rotating body, various rollers and the like are used in consideration of toner releasability, transportability, charging characteristics, durability and heat resistance.

However, since the toner, paper powder, and the like adhere to the roller surface as the number of times of use of these rollers increases, a problem may occur in the transfer paper feeding accuracy, and an image on the transfer paper may be contaminated. There was a problem that the back surface of the transfer paper was stained.

Conventionally, in order to solve these problems in a fixing device, a fixing pad or a web roller, which is a cleaning member, is brought into contact with at least one roller of a fixing roller pair so that the transfer paper is transferred to the roller. The adhesion of powder or the like and the fusion of the toner forming the image on the transfer paper are prevented, and the occurrence of image stains or the like on the transfer paper that is fixed later is prevented.

Further, in the case of a heat roller type fixing device, by controlling the heating roller surface temperature to a constant value, toner adheres to the roller (low temperature offset) due to the roller surface temperature being too low, or too high. As a result, the occurrence of offset related to the fixing temperature such as toner adhesion to the roller (high temperature offset) is suppressed.

On the other hand, in recent years, the demand for personal use of image forming apparatuses has been increasing, so that the size of the image forming apparatus has been reduced, and it has been required to make the fixing device smaller. Also, from the viewpoint of user maintenance-free replacement, regular replacement is required. There has been a demand for an apparatus that eliminates the cleaning member such as the fixing pad described above.

Therefore, a method has been proposed in which the toner is prevented from adhering to the roller as much as possible, instead of being removed after the toner adheres to the roller. For example, by using a material that maintains good releasability for a long period of time on the surface layer of the fixing roller, the toner adhesion suppression force of the roller itself can be increased, and by electrically controlling the potential of the roller, There is a device that repels toner to prevent toner adhesion (electrostatic offset) to the roller due to static electricity due to friction between the roller and transfer paper.

A method has also been proposed in which the toner adhering to the roller is removed without using a cleaning member. For example, as disclosed in Japanese Patent Application No. 2-46750,
A cleaning sheet having an adhesive layer for removing paper dust and toner adhering to the surface of the fixing roller and an antistatic layer for suppressing charge-up due to friction of the transfer paper of the roller is used. In some cases, the offset property is restored by passing the paper through the sheet to extend the life of the fixing roller pair.

[0009]

However, according to the above-mentioned conventional example, even in the apparatus without the cleaning member, it is necessary to detect the temperature of the heating roller surface and control it to a predetermined constant value. Is in contact with the temperature detection element, and a safety device such as a thermoswitch for cutting off the power supply to the heater during abnormal heating and a separation claw for separating the transfer paper from the roller are at least the fixing roller pair. Although the roller is in contact with one side, since the rotation of the roller is always in a constant direction, the toner gradually increases on the contact surface on the upstream side in the roller rotation direction of the contact member such as the temperature detecting element as the number of times of use increases. The following problems may occur due to the accumulation of deposits such as paper and paper dust.

For example, when the adhered matter becomes a certain size, it may slip through the abutting member or may drop from the place where it was accumulated, so that the image on the transfer paper or the back surface of the transfer paper may be soiled. There was something that happened.

Further, if the adhered matter adheres to the separation claw, which is one of the abutting members, it may cause the separation failure of the transfer paper.

Further, there is a problem that when the above-mentioned adhered substance penetrates under the temperature detecting element, the temperature detecting element tends to float from the roller surface, and the roller surface temperature cannot be controlled to a constant value. Similarly, if deposits get caught in the lower part of the thermoswitch, the operation of the safety device will be delayed, which may cause smoke and fire accidents.

The present invention has been made in view of the above problems, and toner and paper powder accumulated on the contact surface of the member, which is in contact with the fixing roller such as the separating claw, on the upstream side in the roller rotation direction. It is a cleaning method capable of removing the adverse effects caused by adherents and the like to extend the life of the fixing device, and omits a cleaning member such as a cleaning pad arranged in contact with the fixing roller and fixing device. It is an object of the present invention to provide a cleaning method for a fixing rotator that can be downsized.

[0014]

SUMMARY OF THE INVENTION According to the present invention, the above-mentioned object is provided with a member abutting on a surface, arranged to rotate while being in pressure contact with each other, and to carry an unfixed developer image. The pair of fixing rotators that perform fixing by nip-conveying the recording material guided to the pressure contact portion is rotated by the drive means in the direction opposite to the rotation direction during fixing, and the cleaning sheet is discharged during fixing. From the side or the entrance side to the pressure contact portion, and while contacting the surface of the fixing rotator pair while conveying the cleaning sheet,
This is achieved by transferring and removing the adhered matter that has accumulated at the contact portion between the member contacting the surface and the surface and transferring it to the cleaning sheet.

[0015]

According to the present invention, when the pair of fixing rotators are rotated by the driving means in the direction opposite to the rotation direction at the time of fixing, the fixing rotator pair stays in the abutting portion of the member abutting on the surface of the fixing rotator. The attached matter is peeled off from the corresponding contact portion and conveyed to the pressure contact portion of the fixing rotator. Then, when the cleaning sheet is made to enter from the discharge side of the pressing portion at the time of fixing, the cleaning sheet is also nipped and conveyed as the fixing rotating body pair rotates, and comes into contact with the surface of the fixing rotating body pair. As a result, the adhering matter conveyed to the pressure contact portion is transferred onto the cleaning sheet, carried on the cleaning sheet, and discharged. Thus, the abutting portion of the abutting member, in particular, the adhering matter staying on the upstream side in the rotational direction at the time of fixing the pair of fixing rotating bodies is reliably removed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First to fifth embodiments of the present invention will be described with reference to the drawings.

<First Embodiment> First, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a heat roller type fixing device used in a laser printer which is an image forming apparatus, and shows a cross section of a main part of the fixing device during normal use. In FIG. 1, reference numeral 1 is a heating roller, which is formed by coating a surface of an aluminum cored bar with PFA resin and has a halogen lamp 3 as a heat source therein. It is adapted to be rotated in the direction of arrow A by a drive gear (not shown). Below the heating roller 1, there is arranged a pressure roller 2 which constitutes a fixing roller pair (hereinafter referred to as a fixing roller pair) together with the heating roller 1. An elastic layer made of silicone rubber, which is covered with a PFA tube on a stainless steel cored bar, is arranged so as to rotate in pressure contact with the heating roller 1.

Further, the heating roller 1 has a separating claw 4,
A thermistor 5 serving as a temperature detecting element and a thermoswitch 6 serving as a safety device are arranged by springs so as to contact the image area on the surface of the heating roller 1. Separation claw 4 is PPS
Is formed by coating PTFE on the surface of a resin, and the thermistor 5 has a PI tape wound around the surface of a silicone sponge in which elements are embedded.
In addition, the thermoswitch 6 is also P on the surface of the aluminum case.
It is a tape wound.

In the apparatus of this embodiment as described above, when the transfer paper 7 which is the recording material carrying the unfixed toner 8 is conveyed after the transfer process, the transfer paper 7 is added to the heating roller 1. The fixing roller pair of the pressure roller 2 nips and conveys it in the direction of the arrow B, and the unfixed toner 8 is fixed on the transfer paper 7 as a permanent image 8 ′ by being heated and pressed in the nip portion, and the paper discharge step. It is discharged to the outside of the printer via (not shown).

Next, a paper passing test conducted by using the fixing device of this embodiment will be described. In this test, a test pattern image in which characters with a printing ratio of about 5% was written using fine particle toner (particle diameter of about 6 μm) was transferred to A4 size transfer paper (grammage 64 g / m ² ) and the transfer paper was printed every minute. Paper is passed through the fixing device at a speed of 8 sheets. As a result of the test, when 5000 sheets of transfer paper are passed, the separating claw 4, the thermistor 5,
A slight amount of toner, paper dust, or other adhering matter was recognized on the upstream side (hatched portion in FIG. 1) of each of the thermoswitches 6 (hereinafter referred to as contact members) in the roller rotation direction. Furthermore, when 10,000 sheets were passed, the amount of adhered substances increased, and image stains on the transfer paper 7 and back stains on the transfer paper occurred at locations corresponding to the positions of the contact members. Most of these stains were at a level that could not be noticed unless the eyes were brought close to the transfer paper and gaze. However, the amount of this stain varies depending on the type of paper to be passed and the toner used, and also depends on how the sheet passes through the contact member and how the transfer sheet is passed. Under certain conditions, as the number of times the fixing device is used increases, the amount of adhered substances such as toner and paper powder accumulates in the shaded portion of FIG.

Therefore, in the present invention, as shown in FIG. 2, the heating roller 1 can be rotated counterclockwise by inserting the cleaning sheet 10 from the discharge side of the fixing device which has passed 10,000 sheets. The cleaning sheet 10 was pulled out in the direction of arrow D by rotating it in the direction of arrow C using a fixing knob (not shown) as a driving means.

As a result, most of the deposits shown by the shaded portions in FIG. 1 leave the abutting member, and the arrow E appears on the surface of the heating roller 1.
Was moved with the rotation of the heating roller 1 and was adhered to the cleaning sheet 10 side at the nip portion of the fixing roller pair to be removed. It was confirmed that the adhered matter could be removed almost completely by rotating the heating roller 1 once. However, it is preferable that the heating roller 1 be rotated twice or more because adhering matter was recognized on the cleaning sheet 10 side even though it was very slight in the second rotation.

Next, the cleaning sheet 10 of this embodiment.
Will be described in detail with reference to FIG. The cleaning sheet 10 has an A3 size (297 × 420 mm) and a thickness of 1
00 μm polyethylene terephthalate sheet base material 12
An adhesive layer 11 having a thickness of about 10 μm is formed on the surface layer of the above, and nothing is provided on the portions 12a and 12b of 10 mm width at the front and rear ends. This is to make it difficult for the sheet to wind around the fixing roller. The pressure-sensitive adhesive layer 11 is formed by applying an acrylic emulsion of an aqueous pressure-sensitive adhesive (Threebond # 1549 manufactured by ThreeBond Co., Ltd.) to the sheet base material 12 and drying it.

In the present embodiment, the adhesive layer was formed only on the side in contact with the heating roller 1, but it is also possible to form the adhesive layer on the side opposite to it to clean the surface layer of the pressure roller 2 at the same time. Is.

<Second Embodiment> Next, a second embodiment of the present invention will be described with reference to FIG. The same parts as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

This embodiment is different from the first embodiment in that a transfer paper on which a solid black image is formed by an image forming apparatus is used as a cleaning sheet. The method of using the cleaning sheet is the same as in the first embodiment.

The cleaning sheet 20 of this embodiment is shown in FIG.
Shown in. The cleaning sheet 20 is a solid black cleaning pattern 21 (see FIG. 4) which is a cleaning layer on an A3 size transfer sheet (grammage 64 g / m ² ) by the image forming apparatus.
The shaded area in) is output. In FIG. 4, arrow F indicates the paper feeding direction. The leading end of the cleaning layer in the transport direction is formed at an angle α with respect to the transport direction instead of 90 °. This is to improve the separation performance of the cleaning sheet 20 from the fixing roller by gradually advancing and discharging the cleaning layer into the nip portion of the fixing roller pair. This angle α is 10 °
If it is 30 ° or more, a very high effect can be obtained. Further, in this embodiment, margins l ₁ and l ₁ ′ are provided at both ends for improving separability, and an angle α ′ is also provided at the rear end side of the cleaning layer 21 in the transport direction. This is to prevent the separation failure from occurring regardless of which direction the user uses the output cleaning sheet 20.

As in the case of the first embodiment, when cleaning was performed using the above-mentioned cleaning sheet 20 on the fixing device after passing 10,000 sheets, the same effect as when using the cleaning sheet 10 shown in FIG. 3 was obtained. It was

On the other hand, when a transfer sheet on which nothing is printed is used as the cleaning sheet, only a part of the adhered matter is adhered to the transfer paper side and is partially left on the heating roller 1 side to completely remove the adhered matter. Could not be removed.

As described above, it can be seen that the solid black pattern as the cleaning layer improves the cleaning effect in this embodiment. This is because the toner image as the cleaning layer is heated when passing through the nip portion between the heating roller 1 and the pressure roller 2, so that the toner melts and exhibits an adhesive property. It is removed by being adhered to and being pressed together with the toner.

Further, the width l ₂ of the solid coating portion is the heating roller 1
A high cleaning effect can be obtained when the amount is one round or more, preferably two weeks or more.

The tip margin l ₁ was set to 4 mm in this embodiment, but since it was not wrapped around the fixing roller,
There is no problem if the width is not less than this level.

<Third Embodiment> Next, a third embodiment of the present invention will be described with reference to FIG. The same parts as those of the first and second embodiments are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, when the number of prints reaches a predetermined number, a cleaning sheet having a solid black cleaning pattern is output from the image forming apparatus, and the cleaning sheet is automatically nipped and conveyed by the fixing roller pair. This is different from the first embodiment.

In this embodiment, a laser printer is used as the image forming apparatus, a counter for counting the number of prints is provided in the laser printer, and the fixing roller pair is modified so as to be able to rotate in reverse by a signal from the controller. Was used. In addition, as transfer paper and cleaning sheet, LETTER size (216 x 279 mm,
Using a paper having a basis weight of 105 g / m ² ), a paper passing test was conducted in the same manner as in the first example.

The cleaning sheet is printed on the transfer paper 5
After passing 000 sheets, as shown in FIG. 5, as a cleaning layer, a solid black pattern 31 having a width of l ₄ (= 180 mm) is formed.
Then, the cleaning sheet 30 having a margin of 1 ₃ (= 6 mm) in width is printed. Further, the conveyance is stopped at a position 20 mm before the rear end of the cleaning sheet 30 enters the nip portion of the fixing roller pair, and immediately after that, a signal is input to the controller so that the fixing roller pair is strongly reversed by one revolution of the heating roller 1. The cleaning sheet was set to be discharged by rotating it to remove the adhering matter shown by the hatched portion in FIG. 1 from the adhesive on the cleaning sheet 30 and then again rotating it normally. As a result, the deposit could be removed at the same level as in the first example.

As described above, according to the present embodiment, the image forming apparatus is provided with the above-mentioned function, so that the paper dust accumulated on the upstream side in the roller rotation direction of the member contacting the heating roller 1 such as the separating claw 4 or the like. It is possible to automatically remove adhered substances such as the above without bothering the user. In addition to the method of outputting the cleaning sheet 30 after the predetermined number of prints as described above, a cleaning key may be provided on the operation panel and the key may be pressed to perform cleaning at any time.

Further, cleaning patterns as shown in FIGS. 4 and 5 are stored in advance in the pattern memory in the image forming apparatus for each paper size, and when a certain number of sheets are passed by the internal counter, the cassette is ejected. A cleaning pattern is regularly set according to the size of the transfer paper inside.
For example, it may be output every time 5000 sheets are passed.

<Fourth Embodiment> Next, a fourth embodiment of the present invention will be described. Note that the description of the common points with the third embodiment will be omitted.

In the present embodiment, the cleaning sheet 30 shown in FIG. 5 is passed through the fixing roller pair in the same manner as in the third embodiment, but the preset temperature of the surface of the heating roller 1 is set to the normal printer temperature 180 only during cleaning. The temperature is controlled to a temperature higher than ℃, and the temperature of the heating roller 1 does not offset the toner at a high temperature, and at the same time, the conveyance speed of the cleaning sheet is 1 / the normal printing speed
It is different from the third embodiment in that the cleaning effect is enhanced to 2.

In addition, in this embodiment, the separating claw 4 in FIG.
In order to forcibly increase the amount of deposits on the upstream side (the shaded area in FIG. 1) of the contact member of the heating roller 1 in the roller rotation direction, the pattern to be printed on the transfer paper used in the paper passing test is printed. It is also different from the third embodiment that the horizontal line is changed to about 30%. According to such a pattern, the amount of the above-mentioned adhered matter after passing 10,000 sheets was considerably larger than the amount in the paper passing test of the third example, and a large proportion of toner in the adhered matter was also found. That is, a cleaning ability higher than that in the third embodiment is required to reliably remove such deposits. The results of the cleaning test in this example will be described below.

In this embodiment, the set temperature of the heating roller 1 is set to about 200 ° C. immediately before the transfer sheet 31 as the base material of the cleaning sheet is fed by the image forming apparatus, and then the solid black portion 32 as the cleaning layer is formed. It is formed on the transfer paper 31 at a normal printing speed. About 20 minutes before the rear end of the cleaning sheet 30 enters the nip portion
The conveyance is stopped at the position of mm, and the subsequent processing is performed in the same manner as in the third embodiment. However, at this time, the heating roller 1 was cleaned by setting the speed at which the heating roller 1 was rotated, that is, the conveying speed of the cleaning sheet 30 to 1/2 of the normal speed.

As a result, despite the large amount of deposits, it recovered to a level close to the initial unattached state, and a high cleaning effect was obtained.

This is because the temperature of the surface of the heating roller 1 to be controlled is set to be high so that the toner fused to the contact member such as the separation claw 4 is easily peeled off, and the toner is slowly rotated in the reverse direction. It is considered that this is because the effect of peeling from the abutting member is enhanced, and this can be reliably removed at the nip portion.

<Fifth Embodiment> Next, a fifth embodiment of the present invention will be described with reference to FIGS. The same parts as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, the cleaning sheet that has entered from the discharge side of the fixing roller pair and discharged from the transfer side is
It is different from the first embodiment in that it is made to enter again from the transfer side and is discharged from the discharge side. In this embodiment, the deposits transferred to the pressure roller side are also removed by such a method.

First, the mechanism of transfer of adhered material to the pressure roller will be described. FIG. 6 shows a method similar to that of the first embodiment.
It shows a state in which the heating roller 1 is rotated counterclockwise by one rotation using the fixing knob attached to the heating roller 1 after passing 000 sheets. On the upstream side of the contact member of the heating roller 1 such as the separation claw 4 in the roller rotation direction in FIG. 6, the symbols of the separation claw 4 are x, the thermistor 5 is y, and the thermoswitch 6 is z. As shown by the hatched portion, paper dust, toner, etc. are attached. When the heating roller 1 is rotated counterclockwise from this state, the adhered substances x, y, z are also moved on the roller surface accordingly.
Then, the adhering matter x is guided to the nip portion of the fixing roller pair, where it adheres to the surface layer of the pressure roller 2 and moves x ₁
And x ₂ remaining on the surface of the heating roller 1 and further rotating as it is, the adhered matter y is now y ₁ and y _2.
Similarly, z is also divided into z ₁ and z ₂ , and FIG. 6 shows a state in which it is stopped after one rotation. In this way, the adhered matter is also transferred to the pressure roller 2.

Next, a method of removing the deposits transferred to the pressure roller 2 will be described. After the above condition,
As shown in FIG. 6, a cleaning sheet 40 having a solid black cleaning pattern output on both sides as shown in FIG. 4 is provided at the nip portion of the fixing roller pair in the direction of arrow G from the transfer paper side, and this time using a fixing knob. Rotate in the direction and pull out slowly toward the paper output side. Then, the adhering substances x ₁ , y ₁ , z ₁ adhering to the pressure roller 2 side and the adhering substances x ₂ , y ₂ , z ₂ adhering to the heating roller 1 side rotate on the surface of each roller. It moves with it and reaches the nip part of the fixing roller pair,
The nip portion is heated and pressed to adhere to the cleaning sheet 40 side and be removed. This state is shown in FIG.

Reference numeral 41 in FIG. 7 denotes A3 size transfer paper (basis weight 64 g / m ² ) which is a cleaning sheet substrate, and 4
Reference numerals 2 and 43 denote solid black cleaning patterns that are cleaning layers formed on the cleaning patterns. The cleaning layer 42 is a deposit x _{2 on the} surface of the heating roller 1 shown in FIG.
y ₂ and z ₂ are removed, and the cleaning layer 43 on the other side is x ₁ ,
This is to remove y ₁ and z ₁ . Thus, these deposits each z ₂ shown in FIG. _{7 ', y 2', x} 2 ' and _{z 1', y 1 ',} x 1' is adhered to the cleaning sheet 40 side as shown by the upper roller Removed cleanly.

[0050]

As described above, according to the present invention,
By rotating the pair of fixing rotators in the direction opposite to that in the normal fixing operation, the member abutting on the pair of fixing rotators accumulates in the contact portion on the upstream side in the rotational direction of the pair of fixing rotators. Peel off adhered materials such as toner and paper powder from the contacted parts,
When the cleaning sheet is fixed by the fixing rotator pair, the cleaning sheet is sent from the paper discharge side or the transfer side (entrance side) to be nipped and conveyed, whereby the adhered matter that has been peeled off can be removed. Therefore, by periodically carrying out the method of the present invention, it is possible to extend the service life of the fixing device and at the same time prevent the transfer sheet from being stained with an image. Further, since a cleaning member such as a fixing pad can be eliminated, a small fixing device can be provided.

[Brief description of drawings]

FIG. 1 is a sectional view showing a schematic configuration of a fixing device used in a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state where the method of the first embodiment is carried out by using the apparatus shown in FIG.

FIG. 3 is a plan view showing a schematic configuration of a cleaning sheet used in the method of the first embodiment.

FIG. 4 is a plan view showing a schematic configuration of a cleaning sheet used in a second embodiment of the present invention.

FIG. 5 is a plan view showing a schematic configuration of a cleaning sheet used in a third embodiment of the present invention.

FIG. 6 is a sectional view of a fixing device for explaining a method of a fifth embodiment of the present invention.

FIG. 7 is a cross-sectional view showing a state of the cleaning sheet after carrying out the method of the fifth embodiment of the present invention.

[Explanation of symbols]

 1 Heating Roller (Rotating Body for Fixing) 2 Pressure Roller (Rotating Body for Fixing) 4 Separation Claw (Abutting Member) 5 Thermistor (Abutting Member) 6 Thermo Switch (Abutting Member) 10 Cleaning Sheet

Claims (3)

[Claims] 1. A member, which is brought into contact with the surface, is arranged so as to rotate while being in pressure contact with each other, and holds and conveys a recording material which carries an unfixed developer image and is guided to a pressure contact portion. The pair of fixing rotators for fixing is rotated by the drive means in the direction opposite to the rotating direction at the time of fixing, and the cleaning sheet is guided from the discharge side of the recording material at the time of fixing to the pressure contact portion, and the cleaning sheet is fixed. While being conveyed, it is brought into contact with the surface of the fixing rotator pair, and the adhered matter accumulated at the contact portion between the member and the surface abutting on the surface is transferred onto the cleaning sheet and removed. A method for cleaning a fixing rotating body. 2. The fixing rotator pair is rotated by the driving means in the same direction as the rotating direction at the time of fixing, and the cleaning sheet is guided from the entrance side of the recording material at the time of fixing of the pressure contact portion of the fixing rotator pair. And conveys the cleaning sheet in the same direction as that at the time of fixing, and before the rear end of the cleaning sheet passes through the pressure contact portion, the fixing rotating body pair is rotated in the opposite direction to the rotation direction by the driving unit to remove the cleaning sheet. After conveying in the direction opposite to that at the time of fixing and bringing it into contact with the surface of the above-mentioned fixing rotator pair, and removing the deposits on the surface,
Again, the driving means rotates the pair of fixing rotators in the same direction as during fixing, and the cleaning sheet is guided from the entrance side of the press contact portion and discharged while being conveyed in the same direction as during fixing. The method for cleaning a fixing rotator according to claim 1. 3. The cleaning sheet is discharged from the recording material entrance side at the time of fixing the pressure contact portion of the fixing rotator pair, and the fixing rotator pair is rotated in a direction opposite to the rotation direction at the time of fixing, The cleaning sheet is guided from the entry side of the pressure contact portion, and the fixing rotating body pair is rotated in the same direction as that at the time of fixing by the driving means, and the surface of the fixing rotating body pair is conveyed while conveying the cleaning sheet. A contact is made to remove deposits on the surface.
The method for cleaning a fixing rotator according to [4].