JP2001209289A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an adhesion resin layer on the surface of a cleaning member from flowing to both ends and to maintain stable cleaning performance in an image forming device equipped with the cleaning member which removes the toner remained on a photoreceptor belt, an intermediate transfer belt, etc. SOLUTION: A heating roller 14 which transfers and fixes a toner image on an intermediate transfer belt 5 onto sheets of paper 18, a cleaning roller 7 which is located on the downstream side from a pressure roller 15 and removes the toner remained on the intermediate transfer belt, and an opposite roller 8 press-contacted with this though the intermediate transfer bolt 5, are provided. In the surface of the cleaning roller 7, resin layer with tackiness by heating is formed, and the width by which this resin layer comes into contact with the intermediate transfer belt 5, is set wider than the width by which the opposite roller 8 comes into contact with the intermediate transfer belt 5 in both sides. It is prevented, thereby, that an adhesion resin flows to the both ends, without heating the adhesion resin near the both ends of the cleaning roller 7 by the opposite roller 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a copying machine or a printer, and more particularly to a method for transferring a toner image from a belt-shaped photosensitive member to recording paper.
A device that forms an image by fixing, or a device that transfers a toner image formed on a belt-shaped photoreceptor or a cylindrical photoreceptor to an intermediate transfer belt, and then transfers and fixes it on paper to form an image It is about.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus using electrostatic transfer, a toner image formed on a photoreceptor belt or an intermediate transfer belt is transferred to a recording medium and simultaneously fixed to form an image. A device has been proposed. In such an image forming apparatus, as a cleaning device for removing residual toner on the belt, the surface of the roller is coated with a toner or a resin having characteristics close to the toner, and the toner or the resin is heated to a predetermined amount to heat the roller. When the toner is applied to the photoreceptor belt or the intermediate transfer belt, the residual toner on the belt is adhered and removed by pressing the photoconductive belt or the intermediate transfer belt (hereinafter, the toner or resin coated on the surface of the cleaning roller is referred to as an adhesive resin). ). There is also a technique for cleaning by heating a metal roller, but after toner adheres to the entire circumference, the configuration is the same as that of the cleaning roller described above. This cleaning roller generates the tackiness of the pressure-sensitive adhesive resin on the surface by heating. Then, by pressing the adhesive resin against the belt, the toner remaining on the belt surface is attached.

[0003] At this time, since the adhesive resin layer is crushed by the pressing load, the adhesive resin flows toward the resin end when both ends of the cleaning roller are open. Sensors (thermistors) 202 for controlling the surface temperature of the cleaning roller 201 are provided at both ends of the cleaning roller as shown in FIGS. 9A and 9B.
When the adhesive resin layer 203 flows into this portion, the sensor 2
02, the rotational force of the cleaning roller 201 is transmitted, and the sensor surface is damaged. In FIG.
A configuration diagram of a sensor 202 for detecting the temperature at this time is shown. Generally, such a sensor 202 is attached with a polyimide film 204 or the like which is excellent in abrasion resistance so as not to damage a mating member (in this case, the core of the cleaning roller 201) that is in contact with the sensor 202 and to reduce the sliding resistance. ing. When the adhesive resin adheres to the polyimide film, the adhesive force with the cleaning roller 201 is large, and the polyimide film is peeled off by the rotational force of the cleaning roller 201. Further, even if the sensor 202 is not damaged, the rotation load becomes large and the drive cannot be performed. Further, as the flow proceeds, the adhesive resin reaches the bearing portion 205 and cannot rotate.

A technique for controlling the flow of such an adhesive resin is disclosed in Japanese Patent Publication No. 6-68652. According to the present invention, the annular protrusion is provided to prevent the adhesive resin on the cleaning roller surface from flowing out from the end. However, in this technique, when the hardness of the annular projection is low, the adhesive resin on the surface of the cleaning roller is heated,
The flow of the resin whose viscosity has been lowered cannot be suppressed, and the resin protrudes. Also, when the hardness of the annular projection is increased and hardened, the annular projection receives pressure at which the adhesive resin on the surface of the cleaning roller contacts the belt to be cleaned,
The contact pressure between the adhesive resin on the surface of the cleaning roller near the annular protrusion and the belt to be cleaned is reduced, and sufficient cleaning cannot be performed. FIG. 11 shows the result of testing the relationship between the contact pressure and the cleaning performance at this time. As can be seen from this graph, if the pressure between the cleaning roller and the belt is low, the residual toner cannot be removed from the belt.

Japanese Patent Publication No. 6-68653 discloses that
As shown in FIG. 12, there is shown a technique in which a rotating guide roller 302 is pressed against both ends of a cleaning roller 301 to stop the flow of a low-viscosity adhesive resin 303.
However, in this technique, even if the flow of the adhesive resin 303 whose viscosity has been reduced is stopped at the portion where the adhesive resin 303 contacts the guide roller 302, the adhesive resin is directed to the end in the circumferential portion of the cleaning roller 301 without the guide roller. And gradually overflows because the adhesive resin cannot be returned. When the guide roller 302 separates from the adhesive resin on the surface of the cleaning roller 301, as shown in FIG.
The adhesive resin 303 is pulled in the direction in which the outer diameter increases, and the end of the adhesive resin swells as shown in FIG. As a result, as shown in FIG. 12C, a gap B is formed near the end where the adhesive resin 303 is raised, and the pressure is not sufficiently applied, so that the cleaning performance is reduced and the residual toner on the belt is removed. I can no longer do it.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to maintain the thickness of the adhesive resin layer on the surface of a cleaning member substantially constant, and to perform cleaning. An object of the present invention is to provide an image forming apparatus capable of achieving stable cleaning maintenance by preventing the adhesive resin from flowing out of a range to be cleaned.

[0007]

According to a first aspect of the present invention, there is provided a toner image carrying belt which carries a toner image on an endless peripheral surface and moves around. In an image forming apparatus for transferring a toner image on the toner image carrying belt to a recording medium or to a recording medium via an intermediate transfer belt, the image forming apparatus has a resin layer on an endless peripheral surface, and heats the resin layer. A cleaning member that removes residual toner on the surface of the toner image carrying belt with adhesive force;
An opposing roller provided at a position opposing the cleaning member via the toner image carrying belt, and pressing the toner image carrying belt against the cleaning member, wherein the opposing roller has a roller surface at a predetermined temperature and The width of the resin layer of the cleaning member in contact with the toner image carrying belt.
An image forming apparatus is provided, wherein the width of the opposite roller is set to be larger on both sides than the width in contact with the toner image carrying belt.

According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the resin layer of the cleaning member is formed by the toner transferred from the toner image carrying belt and adhered thereto. An image forming apparatus is provided.

According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, the cleaning member comprises a metal roller and has a built-in heater. A forming device is provided.

According to a fourth aspect of the present invention, in the image forming apparatus of the first, second or third aspect, the viscosity of the resin layer near both ends in the width direction of the cleaning member is 1.5 ×. An image forming apparatus is provided in which the temperatures of the cleaning member, the opposing roller, and the toner image carrying belt are set so as to be 10 ⁵ Pa · s or more.

According to a fifth aspect of the present invention, in the image forming apparatus according to the first, second, third or fourth aspect, the toner image carrying belt is formed of the cleaning member and the opposed roller. An image forming apparatus is provided which is in contact with one or both of them in a predetermined range so as to be wound.

In the image forming apparatus according to the first aspect of the present invention, the resin layer formed on the endless peripheral surface of the cleaning member is heated, and the toner image carrying belt is pressed against the cleaning member by the opposing roller, whereby the toner image is formed. The residual toner on the surface of the carrying belt can be removed by attaching it to the resin layer. At this time, the opposing roller has a built-in heater for heating the roller surface to a predetermined temperature, and adjusts the temperature of the residual toner to a predetermined temperature at which the residual toner easily adheres to the resin layer. At this time, the width at which the resin layer of the cleaning member comes into contact with the toner image carrying belt is set to be larger on both sides than the width at which the opposing roller comes into contact with the toner image carrying belt. The contacting toner image carrying belt is not heated by the opposing roller. Thus, the temperature of the portion of the cleaning member that contacts both ends of the adhesive resin layer can be reduced. As a result, the viscosity of the resin near both ends in the width direction of the cleaning member surface increases,
The adhesive resin is less likely to flow. Therefore, it is possible to prevent the occurrence of defective cleaning due to the flow of the adhesive resin toward both ends of the cleaning roller.

Further, the resin layer of the cleaning member can be formed by the toner transferred from the toner image carrying belt and adhered to the cleaning member. There is no need to provide a resin layer on the surface.

According to a third aspect of the present invention, the cleaning member can be constituted by a metal roller having a built-in heater. The toner transferred from the toner image carrying belt adheres to the surface of the metal roller, and the heater is heated. , It is possible to form an adhesive resin layer on the surface of the metal roller. Therefore, there is no need to provide a resin layer on the surface of the cleaning member in advance.

In the image forming apparatus according to the fourth aspect, by appropriately setting the temperatures of the cleaning member, the opposing roller, and the toner image carrying belt, the viscosity of the resin layer near both ends in the width direction of the cleaning member is reduced. , 1.5 × 1
0 ⁵ Pas or more, so that the resin near both ends of the cleaning member is prevented from flowing,
The occurrence of defective cleaning can be more reliably prevented.

In the image forming apparatus according to the present invention, the toner image carrying belt is in contact with the cleaning member and / or the opposing roller within a predetermined range so as to be wound therearound. The contact time with the cleaning member or the opposing roller becomes longer, and only the central portion except for both end portions where the toner image carrying belt does not contact the opposing roller is sufficiently heated. Therefore, when the toner image carrying belt comes into contact with the cleaning member, the temperature at both ends of the toner image carrying belt is low, and the adhesive resin near both ends of the cleaning member is sufficiently cooled by the toner image carrying belt. . For this reason, it is possible to more reliably prevent the resin near the both ends of the cleaning member from flowing.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing an image forming apparatus according to an embodiment of the invention described in claim 1, claim 2, claim 3 or claim 4. The image forming apparatus includes an endless intermediate transfer belt 5 whose peripheral surface is rotatably supported, and forms yellow, magenta, cyan, and black toner images at a position facing the intermediate transfer belt 5. Four image forming units 10a, 10b,
10c and 10d are provided. Each of the image forming units 10a, 10b, 10c, and 10d has a photosensitive drum 1 on the surface of which an electrostatic latent image is formed. A charging device 2 for uniformly charging; an optical scanning device 3 for writing an electrostatic latent image by scanning the surface of the photosensitive drum with a laser beam; and selectively transferring toner to a latent image formed on the photosensitive drum The image forming apparatus includes a developing device 4 that forms a toner image by causing the toner image on the photosensitive drum 1 to be primarily transferred onto an intermediate transfer belt 5 by a transfer charger 6.

A drive roller 11, a support roller 12, a peeling roller 13, and a heating roller 14 are arranged inside the intermediate transfer belt 5, and the intermediate transfer belt 5 is stretched around these to make the drawing possible. It moves around in the direction of the arrow shown therein. At a position opposed to the heating roller 14 with the intermediate transfer belt 5 interposed therebetween, a pressure roller 15 for pressing the paper 18 toward the heating roller 14 is disposed.
And the sheet 18 is conveyed between them.

Further, a heating plate 16 for heating the toner image on the intermediate transfer belt is provided along the back side of the intermediate transfer belt 5 on the upstream side of the heating roller 14 in the circumferential direction of the intermediate transfer belt 5. ing. On the downstream side of the heating roller 14 in the circumferential direction of the intermediate transfer belt 5,
A cooling plate 17 for cooling the toner image adhered to the paper 18 is provided. Further, on the downstream side of the cooling plate 17 in the circumferential direction of the intermediate transfer belt 5, a cleaning roller 7 that comes into contact with the surface of the intermediate transfer belt 5 and removes residual toner, and the cleaning roller 7 and the intermediate transfer belt 5 are interposed. An opposing roller 8 is provided which is pressed into contact.

The heating roller 14 and the pressure roller 15 are internally provided with heaters 14a, 14a such that the surface of each roller is at a predetermined temperature (for example, the melting temperature of toner or higher).
5a are provided respectively. Further, the peeling roller 13
The sheet 18 is peeled off from the intermediate transfer belt 5 at the portion of, and is discharged as a print. At this time, if the temperature of the intermediate transfer belt 5 at the time of peeling is lowered by the cooling plate 17 from the time of fixing, the peeling becomes easy.

The intermediate transfer belt 5 for simultaneously performing transfer and fixing needs to have electrical characteristics for performing transfer from the photosensitive drum 1, and further needs heat resistance for performing transfer and fixing. It is. Further, it is necessary that the toner image to be transferred to the sheet 18 after transfer and fixing be separated from the intermediate transfer belt 5 so as to have releasability. Therefore, the intermediate transfer belt 5 has a configuration in which a surface of a heat-resistant polyimide or the like whose electric resistance is controlled is coated with a silicone rubber or the like for improving the releasability.

Inside the cleaning roller 7, there is provided a heater 7a for heating the surface of the adhesive resin so as to have an optimal adhesiveness. Further, the intermediate transfer belt 5
A heater 8a for heating the intermediate transfer belt 5 is also provided inside the opposing roller 8 which is pressed against the cleaning roller 7 through the intermediate transfer belt 5 so that the viscosity of the toner remaining on the surface of the intermediate transfer belt 5 becomes optimal for cleaning. Is provided.
An adhesive resin layer may be formed on the surface of the cleaning roller 7 in advance, but the cleaning roller is formed of a metal roller, and is transferred from the intermediate transfer belt 5 in the image forming process, and the adhesive resin layer is formed by the attached toner. It may be formed.

In general, the width of the opposing roller 8 must be equal to or larger than the maximum sheet width to be used. However, when the image forming area is smaller than the sheet width, it may be set wider than the maximum image forming area. In addition, when printing marks for image control (position, density, etc.) outside the paper width, these are set to a width that can be cleaned. Then, as shown in FIG. 2B, the width of the adhesive resin layer of the cleaning roller 7 is
The width is determined by adding a predetermined length to both sides from the width at which the opposing roller 8 contacts the intermediate transfer belt 5. Further, the width of the intermediate transfer belt 5 is set to be equal to or greater than the width of the cleaning roller 7. With such a configuration, since both ends in the width direction of the intermediate transfer belt 5 do not contact the opposing roller 8, the temperature of these portions does not increase. Then, the temperature of the both ends of the adhesive resin layer on the surface of the cleaning roller 7 which comes into contact with the portion where the temperature of the intermediate transfer belt 5 does not rise is reduced because heat is taken by the intermediate transfer belt 5.

The pressure-sensitive adhesive resin has a correlation between temperature and viscosity. If the temperature is low, the viscosity increases and the resin does not flow. FIG.
(A) and (c) show the temperature of the adhesive resin on the surface of the cleaning roller 7 actually measured. Also in FIG.
The relationship between the temperature and the viscosity characteristics of a resin as a general toner raw material is shown. In this embodiment, the temperature of the roller surface is set to 120 ° C. in order to make the viscosity of the adhesive resin of the cleaning roller 7 10 ⁴ Pa · s which is optimal for cleaning.
The temperature of the opposing roller 8 is set to 140 ° C. since the contact time with the intermediate transfer belt 5 is short, so that the temperature of the intermediate transfer belt 5 is about 125 ° C. Both ends of the adhesive resin on the surface of the cleaning roller 7 are in contact with the intermediate transfer belt 5 at portions not in contact with the surface of the opposing roller 8, and the temperature of the intermediate transfer belt is about 70 ° C. The surface temperature of the adhesive resin layer near both ends in the width direction is 85 ° C., and the viscosity is 10 ⁶
Pa · s, high viscosity and difficult to flow.

With the above configuration, it is possible to prevent the adhesive resin on the surface of the cleaning roller 7 from flowing to both ends in the width direction. The cleaning roller 7
Since the flow of the adhesive resin is not locally suppressed at both ends of the cleaning roller, the profile of the adhesive resin layer on the cleaning roller surface is also kept smooth, and the cleaning performance can be maintained for a long time.

The fluidity of the adhesive resin on the surface of the cleaning roller 7 is also affected by the pressure at the contact portion between the cleaning roller 7 and the intermediate transfer belt 5. FIG.
(B) shows the relationship between the pressure of these contact portions and the fluidity of the toner resin. In this figure, ΔX corresponds to FIG.
As shown in (a), the amount of movement of the adhesive resin on the cleaning roller surface per unit time is shown. The pressure at the contact portion between the cleaning roller 7 and the intermediate transfer belt 5 is set to 0.
In the case of 50 to ² N / mm ² , in order to stop the flow of the adhesive resin, the winding amount of the intermediate transfer belt 5 is adjusted so that the resin temperature becomes such that the viscosity becomes 1.5 × 10 ⁵ Pa · s or more. It is necessary to set the temperature of the opposing roller 8 and the like.

Next, the operation of the image forming apparatus will be described. Four image forming units 10a, 10b, 10c, and 10d are arranged around the intermediate transfer belt 5, and in each image forming unit, the photosensitive drum 1 is almost uniformly charged by the charging device 2. Thereafter, exposure is performed by the optical scanning device 3 which is turned on and off based on the image signal, and an electrostatic latent image is formed on the surface of the photosensitive drum 1. The electrostatic latent image on each photosensitive drum 1 is developed by a developing device 4 containing yellow, magenta, cyan, and black toners, and a so-called digital image toner image representing density by area modulation is formed. It is formed on each photosensitive drum 1. On the other hand, the intermediate transfer belt 5 is rotated by the driving roller 11, and the toner images of the respective colors formed on the respective photosensitive drums 1 are sequentially transferred onto the intermediate transfer belt 5 by the transfer charger 6 in a superimposed manner. , Intermediate transfer belt 5
A toner image on which a plurality of colors are superimposed is formed. The plurality of color toner images formed on the intermediate transfer belt 5 are preheated when the intermediate transfer belt 5 passes through a position facing the heating plate 16, and are conveyed to a position where the heating roller 14 is disposed.

On the other hand, the paper 1
8 is conveyed between the intermediate transfer belt 5 holding the toner images of the plurality of colors and the pressure roller 15 at the same time, and is heated and heated while being sandwiched between the heating roller 14 and the pressure roller 15. Pressed. Then, the toner heated above the melting temperature is softened and melted, and permeates the paper 18. This toner image is conveyed to the cooling plate 17 while being in contact with the intermediate transfer belt 5 and the sheet 18, and is cooled and cooled to a melting temperature or lower to be agglomerated and solidified. Therefore, at the position where the peeling roller 13 having a small radius of curvature is disposed, the sheet 18 is separated from the intermediate transfer belt 5 together with the toner by the stiffness of the sheet itself, and a color image is formed.

Thereafter, the toner remaining on the intermediate transfer belt 5 is conveyed to a position facing the cleaning roller 7 and the pressure roller 8 as the intermediate transfer belt 5 moves around. Then, the residual toner on the surface of the intermediate transfer belt comes into contact with the adhesive resin of the cleaning roller 7 and is removed by being attached thereto. The cleaning roller 7 is retracted to a position where it does not come into contact with the intermediate transfer belt 5 while the intermediate transfer belt 5 is stopped, such as when the apparatus is stopped or in a standby state, to prevent deformation of the cleaning roller surface due to pressure of the adhesive resin. . Then, the apparatus starts operation, the cleaning roller 7 comes into contact after the intermediate transfer belt 5 starts rotating, the image forming process ends, and the intermediate transfer belt 5 returns to the standby position again before the rotation stops.

In the above-described image forming apparatus, both end portions of the adhesive resin layer on the surface of the cleaning roller 7 are in contact with the portion where the temperature of the intermediate transfer belt 5 does not increase without coming into contact with the opposing roller 8, and heat is transferred to the intermediate transfer belt 5. The temperature is lowered because the belt 5 is robbed. Since the temperature of the intermediate transfer belt is about 70 ° C., the surface temperature near both ends of the adhesive resin is 85 ° C.
At 10 ° C., the viscosity becomes 10 ⁶ Pa · s, and the viscosity is so high that it becomes difficult to flow. Therefore, it is possible to prevent the flow of the adhesive resin on the surface of the cleaning roller 7 and prevent the cleaning performance from lowering.

When the temperature of the adhesive resin layer on the surface of the cleaning roller 7 and the temperature of the residual toner on the intermediate transfer belt 5 greatly exceed the above-mentioned values, the cohesive force inside the resin is reduced and the resin is separated. Since the adhesive resin on the surface 7 is divided and adheres to the intermediate transfer belt, cleaning cannot be performed. Further, as the number of times of cleaning increases, the thickness of the adhesive resin layer of the cleaning roller 7 increases. As a result, heat conduction decreases, and the cleaning roller 7
The temperature of the resin layer surface decreases, and the cleaning performance also decreases. In such a case, as shown in FIGS. 5A and 5B, it is desirable to attach the blade 29 while maintaining a certain gap in the cleaning roller 27, and heat the blade 29 by the heater 30. FIG. 5 (c)
As shown in (2), the thickened resin layer 31 on the surface of the cleaning roller 27 can be scraped off by the blade 29, and the cleaning roller 27 can be restored to the original performance. As a raw material of the toner constituting the resin layer, a polyester resin or the like is used, but since such a polymer material has a low thermal conductivity, it is desirable to control the thickness in a range of about 0.5 to 1 mm. .

FIG. 6 shows claims 1, 2, 3,
FIG. 7 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention. This image forming apparatus includes four image forming units 50a, 50b, and 50 each including a photosensitive drum 41, a charging device 41, a developing device 44, a transfer charger 46, and the like, similarly to the image forming device shown in FIG.
c, 50d, the intermediate transfer belt 45, and the heating plate 5
6, a heating roller 54, a pressure roller 55, a cooling plate 57, a driving roller 51, and a peeling roller 53.
8 is different.

In the image forming apparatus shown in FIG. 6, the intermediate transfer belt 45 is wound around the opposing roller 48 within a predetermined range, and the intermediate transfer belt 45 is wound around the cleaning roller 47 at a position downstream of the range. ing. FIG. 7 shows the opposing roller 48 and the cleaning roller 4.
7 shows the details of the portion around which the intermediate transfer belt 45 is wound and the result of measuring the temperature distribution of the adhesive resin on the surface of the cleaning roller 47. As shown in this figure, the surface temperature of the cleaning roller 47 is set to 120 ° C., and the surface temperature of the opposing roller 48 is set to 110 ° C. The adhesive resin layers at both ends in the width direction of the cleaning roller 47 are attached to the intermediate transfer belt 45 not in contact with the opposing roller 48.
, And the temperature of the intermediate transfer belt 45 is about 70 ° C., so that the temperature near both ends of the adhesive resin layer is 90 ° C.
And the viscosity can be adjusted to a desired viscosity at which the adhesive resin does not easily flow.

In the case of a high-speed image forming apparatus, as in the image forming apparatus shown in FIG. 1, when heat is exchanged only in the pressurizing section, the intermediate transfer belt is heated to a predetermined temperature for cleaning. Means that the temperature of the opposing roller must be raised, and immediately after the intermediate transfer belt stops rotating,
There is a problem that the temperature of the intermediate transfer belt is excessively increased due to the overshoot, resulting in thermal deterioration. In addition, if the contact time between the intermediate transfer belt and the cleaning roller is short, there is a problem that the end of the adhesive resin of the cleaning roller is not sufficiently cooled by the intermediate transfer belt and the flow of the adhesive resin cannot be stopped. In the image forming apparatus shown in FIG. 6, the intermediate transfer belt 45 is wound around the opposing roller 48 and the cleaning roller 47, so that the contact time between the intermediate transfer belt 45 and the intermediary transfer belt 45 is increased. Heat can be conducted. For this reason, it is possible to control the target roller 48 at a target temperature without setting it higher than necessary.

The amount of winding of the intermediate transfer belt 45 around the opposing roller 48 and the cleaning roller 47 needs to be set according to the speed of the intermediate transfer belt 45, the viscosity characteristics of the toner polymer depending on the temperature, and the like. In order to optimize the cleaning performance, the temperature at which the adhesive resin on the surface of the cleaning roller 47 has a predetermined viscosity, the temperature at which the residual toner on the intermediate transfer belt 45 has a predetermined viscosity,
Further, it is necessary to manage the temperature at which the viscosity of the adhesive resin on the surface of the cleaning roller 47 becomes such that the adhesive resin does not flow, similarly to the embodiment shown in FIG.

FIG. 8 is a circuit diagram showing a first embodiment of the present invention.
FIG. 13 is a schematic configuration diagram illustrating an image forming apparatus according to another embodiment of the invention described in claim 4 or 5. The image forming apparatus includes an endless photosensitive belt 6 that moves around in a certain direction.
And a charging device 62 around the photosensitive belt 61 for charging the surface of the photosensitive belt 61 substantially uniformly.
And an optical scanning device 63 that scans the photosensitive belt with image light corresponding to an image signal to write an electrostatic latent image, and transfers toner to the electrostatic latent image formed on the photosensitive belt to form a toner image. And a developing device 64.

Inside the photosensitive belt 61, a driving roller 71, a peeling roller 73, a heating roller 74, and an opposing roller 68 are arranged. It moves around in the direction indicated by the arrow. Heating roller 74 and photosensitive belt 61
The sheet 78 is placed at a position facing the
A pressure roller 75 is disposed to press the sheet 18 between the pressure roller 75 and the photosensitive belt 61 by a transport unit (not shown).

Further, a heating plate 76 for heating the toner image on the photosensitive belt 61 is provided on the upstream side of the heating roller 74 in the circumferential direction of the photosensitive belt 61, and on a sheet 78 on the downstream side of the heating roller 74. A cooling plate 77 for cooling the adhered toner image is provided. Also,
The photosensitive belt 61 is located at a position where it contacts the opposing roller 68 disposed inside the photosensitive belt 61 via the photosensitive belt 61.
A cleaning roller 57 that contacts the surface of the cleaning roller 1 and removes residual toner is provided. The photosensitive belt 61 is wound around the opposing roller 68 in a predetermined range, and the photosensitive belt 61 is wound around the cleaning roller 57 in a predetermined range at a position downstream of the range.

In such an image forming apparatus, the photosensitive belt 61 is driven by the driving roller 71, is charged by the charging device 62, and is scanned with the image light by the optical scanning device 63 to form a latent image on the surface. This latent image is developed by the developing device 64, and a toner image is formed on the surface of the photosensitive belt 61. This toner image is pre-heated by the heating plate 76 and then conveyed in time with the toner image.
The toner image on the photosensitive belt 61 is heated and pressed by the heating roller 74 and the pressing roller 75 together with
Is established.

The heating roller 74 and the pressure roller 75 are provided with heaters 74a and 75a therein so that the surface of each roller is at a predetermined temperature. Further, the sheet 78 is separated from the photosensitive belt 61 at the separation roller 73 after the toner image is transferred and fixed on the surface thereof, and is separated and discharged as a print. At this time, the cooling plate 77
Thereby, the photosensitive belt 61 is cooled to a predetermined temperature. Then, the toner remaining on the surface of the photosensitive belt is removed by the cleaning roller 67. Cleaning roller 67
Can be cleaned using the same configuration as the embodiment shown in FIGS. 1 and 6, and the basic characteristics are the same, so that the detailed description is omitted here. Although only one developing device 64 is shown in the configuration of the photosensitive belt 61 illustrated in FIG. 8, a configuration in which the photosensitive belt 61 is rotated a plurality of times using the developing devices 64 of a plurality of colors to form a color image is provided. Is known, and the present invention can be used similarly. Further, the present invention can be similarly applied to an apparatus for forming a color image while the photosensitive belt makes one rotation by using a plurality of exposure devices (ROS) and developing devices, and transferring and fixing the image on paper.

[0041]

As described above, according to the image forming apparatus of the present invention, it is possible to lower the temperature near both ends of the adhesive resin formed on the surface of the cleaning roller and to reduce the fluidity of the adhesive resin. Therefore, the pressure-sensitive adhesive resin flowing to the end of the cleaning roller due to the pressure at the time of cleaning can be suppressed without any additional function. In addition, the pressure-sensitive adhesive resin swells at the suppressed portion, and the pressure between the cleaning roller and the toner image carrying belt (member to be cleaned) does not become uneven, and the residual toner on the surface of the toner image carrying belt can be stably removed. At the same time, it is possible to prevent a decrease in cleaning performance.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic view showing the vicinity of an opposing portion between a cleaning roller and an opposing roller used in the image forming apparatus shown in FIG.

FIG. 3 is a graph showing a relationship between temperature and viscosity of a toner resin in the image forming apparatus shown in FIG.

FIG. 4 is a graph showing the relationship between the viscosity of the adhesive resin and the flow amount depending on the pressure of the cleaning roller in the image forming apparatus shown in FIG.

FIG. 5 is a diagram illustrating an example in which a blade is disposed at a position facing a surface of a cleaning roller.

FIG. 6 is a schematic configuration diagram illustrating an image forming apparatus according to a second embodiment of the present invention.

FIG. 7 is a schematic diagram showing the vicinity of an opposing portion between a cleaning roller and an opposing roller used in the image forming apparatus shown in FIG.

FIG. 8 is a schematic configuration diagram illustrating an image forming apparatus according to a third embodiment of the present invention.

FIG. 9 is a schematic configuration diagram illustrating an example of a cleaning roller and a sensor used in a conventional image forming apparatus.

10 is a diagram illustrating a problem when the adhesive resin on the surface of the cleaning roller flows in the image forming apparatus illustrated in FIG. 9;

FIG. 11 is a diagram illustrating various factors that affect cleaning performance in a conventional image forming apparatus.

FIG. 12 is a schematic configuration diagram illustrating another example of a cleaning roller and a guide roller used in a conventional image forming apparatus.

[Explanation of symbols]

 1,41 Photoreceptor drum 2,42,62 Charging device 3,43,63 Optical scanning device 4,44,64 Developing device 5,45 Intermediate transfer belt 6,46 Transfer charger 7,27,47,67 Cleaning roller 8 , 48, 68 Opposing roller 10, 40 Image forming unit 11, 51, 71 Driving roller 12 Supporting roller 13, 53, 63 Stripping roller 14, 54, 74 Heating roller 15, 55, 75 Pressure roller 16, 56, 76 Heating Plate 17, 57, 77 Cooling plate 18, 58, 78 Paper 29 Blade 30 Heater 61 Photosensitive belt

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hiroaki Awano 430 Nakaicho, Nakaicho, Ashigarakami-gun, Kanagawa Green Tech Nakai Inside Fuji Xerox Co., Ltd. F-term (reference) 2H032 BA09 BA23 BA30 2H034 BC01 BC03

Claims (5)

[Claims] 1. A toner image carrying belt that carries a toner image on an endless peripheral surface and moves around, and records the toner image on the toner image carrying belt on a recording medium or via an intermediate transfer belt. An image forming apparatus for transferring to a medium, a cleaning member having a resin layer on an endless peripheral surface, and removing residual toner on the surface of the toner image carrying belt by the adhesive force of the heated resin layer; And a facing roller provided at a position facing the toner image carrying belt via the toner image carrying belt, and pressing the toner image carrying belt against the cleaning member, wherein the facing roller has a roller surface at a predetermined temperature. The width in which the resin layer of the cleaning member is in contact with the toner image carrying belt is the width in which the opposed roller is in contact with the toner image carrying belt. Ri, the image forming apparatus characterized by being largely set on both sides. 2. The image forming apparatus according to claim 1, wherein the resin layer of the cleaning member is formed of toner transferred from the toner image carrying belt and adhered thereto. 3. The image forming apparatus according to claim 1, wherein the cleaning member includes a metal roller and has a built-in heater. 4. The cleaning member, the opposing roller, and the resin layer, wherein the viscosity of the resin layer near both ends in the width direction of the cleaning member is 1.5 × 10 ⁵ Pa · s or more.
4. The image forming apparatus according to claim 1, wherein a temperature of the toner image carrying belt is set. 5. The image forming apparatus according to claim 1, wherein the toner image bearing belt is in contact with one or both of the cleaning member and the opposing roller within a predetermined range so as to be wound therearound. The image forming apparatus according to claim 3.