JP2003098842A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device which stably forms high-quality images by providing a transcriber cleaning means, comprising an updating mechanism which automatically updates a cleaning web that cleans the transcriber, to keep the transcribing performance of the transcriber well. SOLUTION: A support means is made to turn to bridge a cleaning web in between a main shaft and a take-up shaft, and a transcriber is cleaned with a cleaning web which is automatically updated. A roll of cleaning web is formed on the take-up shaft to automatically deliver the cleaning web for updating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus used in a copying machine, a facsimile, a printer, etc., and more particularly, it forms a toner image by an electrophotographic method and forms a toner image on a recording material by using a transfer body. Image forming apparatus.

[0002]

2. Description of the Related Art Generally, an electrophotographic image forming apparatus forms a toner image on an image carrier composed of a photoconductor by charging, exposing and developing, and transfers the formed toner image to fix the image. An image is formed on the material. Further, in an image forming apparatus often used for color image formation, an intermediate transfer belt is used as an image carrier, and the toner image formed on the photoconductor in the same process as described above is transferred to the intermediate transfer belt and then the intermediate transfer belt is transferred. An image forming process is performed in which the image is transferred from the transfer belt to a recording material and fixed.

An electrostatic transfer method is often used for transferring the toner image in the image forming step. This electrostatic transfer method uses the electric charge of the toner particles, and by applying an electric field that moves the toner particles to the recording material,
This is a method of transferring a toner image from an image carrier to a recording material.

In contrast to the electrostatic transfer method, there is a transfer simultaneous fixing method in which transfer and fixing are performed simultaneously. In the simultaneous transfer and fixing method, a material having a low surface energy such as silicon rubber or fluororesin is used as a transfer body carrying a toner image, and the toner image is formed by utilizing a difference in adhesive force between the transfer body and a recording material with respect to toner particles. This is a method of transferring from a transfer body to a recording material.

In the simultaneous transfer and fixing method, the toner particles are heated and deformed at the time of transfer in order to increase the contact area of the toner particles with the recording material so as to increase the adhesion of the individual toner particles to the recording material. As a result, transfer and fixing are performed simultaneously. Therefore, in this transfer method, a transfer body made of a heat resistant material is used as the transfer body.

In the electrostatic transfer method, toner particles are likely to be scattered or are easily influenced by the environment, whereas
The simultaneous transfer and fixing method does not have such a problem, so that a clear and high-quality image can be formed.

[0007]

As described above, in the simultaneous transfer and fixing method, the transfer body is made of a heat-resistant material, and transfer is performed at an extremely high transfer rate. It adheres and accumulates as the image forming process is repeated. Therefore, in order to actually apply the image forming process using the transfer body, a cleaning means for cleaning the transfer body is required.

In the conventional image forming apparatus using the transfer body,
There has been no cleaning means that maintains good performance of the transfer body and has a high cleaning performance for a long period of time. Alternatively, the conventional cleaning means has a problem that maintenance is required to maintain the cleaning performance.

The present invention provides an image forming apparatus capable of forming a high quality image over a long period of time by solving the problems associated with the cleaning of the transfer body in the conventional image forming process using the transfer body. The purpose is to do.

[0010]

The above-mentioned objects of the present invention are as follows.
It is achieved by the following invention.

1. An image carrier, a toner image forming means for forming a toner image on the image carrier,
A transfer member to which the toner image on the image carrier is transferred, a transfer fixing unit that transfers and fixes the toner image on the transfer member to a recording material by heating and deforming toner particles, and the transfer member after transfer. In the image forming apparatus having a cleaning unit for cleaning the
A cleaning web, a main winding shaft of the cleaning web,
The cleaning web take-up shaft, the main take-up shaft and the take-up shaft are included, and the cleaning web has an inlet / outlet for supporting the cleaning web between the main take-up shaft and the take-up shaft. By having a rotatable supporting means for contacting the body and a driving means for driving the winding shaft, cleaning is performed by the cleaning web on the supporting means, and the cleaning web is wound by the driving means. An image forming apparatus, which updates the cleaning web.

2. 2. The image forming apparatus as described in 1 above, wherein in the cleaning step of the transfer body, the supporting means moves in the same direction with respect to the transfer body and at substantially the same speed.

3. In the first circulation of the transfer member and the second circulation that is continuous with the first circulation,
3. The image forming apparatus according to 1 or 2 above, wherein the entrance and exit do not face each other at the same position on the transfer body.

4. 4. The cleaning web, the original winding shaft, the winding shaft, and the supporting means are formed in a unit that is attachable to and detachable from the main body of the image forming apparatus. Image forming device.

5. An image carrier, a toner image forming means for forming a toner image on the image carrier,
A transfer member to which the toner image on the image carrier is transferred, a transfer fixing unit that transfers and fixes the toner image on the transfer member to a recording material by heating and deforming toner particles, and the transfer member after transfer. In the image forming apparatus having a cleaning unit for cleaning the
A cleaning web, a roll supporting the roll of the cleaning web, and a winding shaft for bringing the outermost layer of the roll into contact with the transfer body, and a driving means for driving the winding shaft are provided, and cleaning is performed by the cleaning web of the outermost layer. The image forming apparatus is characterized in that the cleaning web is updated by the driving means.

6. 6. The image forming apparatus as described in 5 above, wherein the drive unit rotates the winding shaft in a direction opposite to that during cleaning.

7. 7. The image forming apparatus according to 5 or 6, further comprising a removing unit that removes a portion of the used cleaning web from the roll.

8. 8. The image forming apparatus according to 7, wherein the cleaning web includes a plurality of update units of the cleaning web having a predetermined length, and the removing unit removes the update unit from the roll.

9. 8. The image forming apparatus as described in 7 above, further comprising a cutting unit that cuts the cleaning web into predetermined lengths.

10. 10. The image forming apparatus according to 9, wherein a cutting auxiliary line is provided for each of the predetermined lengths of the cleaning web, and the cutting unit cuts the cleaning web along the cutting auxiliary line.

11. 10. The image forming apparatus according to the above 9, wherein the cutting unit is a blade member.

12. 10. The image forming apparatus according to any one of 7 to 9 above, wherein the removing unit has a peeling claw that peels off an end portion of the cleaning web.

13. 13. The image forming apparatus according to 12, wherein the cleaning web has a width wider than an image width, and the peeling claw includes a peeling claw for peeling the cleaning web at a portion outside the image width. .

14. 13. The image forming apparatus according to 12, wherein the peeling claw moves in a width direction of the cleaning web to perform peeling.

15. The winding shaft is detachably attached to the main body of the image forming apparatus.
The image forming apparatus according to any one of 4 above.

16. 16. The driving unit moves the cleaning web at a speed of 1/2 to 1/10 of a moving speed of the cleaning web when cleaning the transfer body. The image forming apparatus described.

17. 16. The image forming apparatus according to any one of 1 to 15 above, wherein the drive unit moves the cleaning web at a low speed during cleaning to update the cleaning web.

18. 17. The image forming apparatus according to any one of 1 to 16 above, further comprising control means for periodically operating the drive means to update the cleaning web.

19. The detection means for detecting dirt on the cleaning web, and the control means for operating the drive means to update the cleaning web based on a dirt detection signal from the detection means.
The image forming apparatus according to any one of items 1 to 16.

20. 20. The control means for activating the driving means to update the cleaning web when the image forming apparatus is stopped due to a predetermined cause, as described in any one of 1 to 19 above. Image forming apparatus.

21. 21. The image forming apparatus according to any one of 1 to 20 above, further comprising a separating unit that separates the transfer body from the cleaning web when the cleaning web is updated.

22. Update the cleaning web,
21. The image forming apparatus according to any one of 1 to 20 above, which is performed while the transfer body and the cleaning web are in contact with each other and while the transfer body is being moved.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Image Forming Apparatus> FIG. 1 is a diagram showing an example of an image forming apparatus according to an embodiment of the present invention.

The illustrated image forming apparatus is a color image forming apparatus using a plurality of process units, an intermediate transfer belt, and a transfer body. The toner image formed in each process unit is transferred to the intermediate transfer belt, and is superimposed on the intermediate transfer belt to form a color toner image,
The formed color toner images are collectively transferred to the transfer body and then collectively transferred from the transfer body to the recording material.

Intermediate transfer belt 14 which is an example of an image carrier
Around a, a process unit PU for a yellow (Y) image, a magenta (M) image, a cyan (C) image, and a black (K) image
(Y), PU (M), PU (C), and PU (K) are provided, and toner images of Y, M, C, and K are formed in each process unit, and the toner images are the intermediate transfer belt 14a.
The transferred color toner images are superposed on each other, and the transferred color toner images are collectively transferred to a heat resistant transfer belt 21 as a transfer body.

Process units PU (Y), PU
Since (M), PU (C), and PU (K) have a common structure, one set will be described. The photoconductor drum 10, which is an image forming body, is formed by forming a photoconductor layer of a conductive layer and an organic photosensitive layer (OPC) on the outer periphery of a cylindrical base.

The photosensitive drum 10 is rotated in the clockwise direction indicated by the arrow with the conductive layer grounded by the power from a driving source (not shown) or by following the intermediate transfer belt 14a.

Reference numeral 11 denotes a scorotron charger as a charging means, which is attached in close proximity to the photosensitive drum 10 in a direction orthogonal to the moving direction of the photosensitive drum 10.
By the corona discharge of the same polarity as the toner, the photosensitive drum 1
A uniform potential is applied to 0.

Reference numeral 12 denotes an exposure optical system as an image exposure means for performing Y, M, C and K image exposure based on image data.
For example, it is a scanning optical system that performs scanning in parallel with the rotation axis of the photosensitive drum 10 by a polygon mirror or the like. A latent image is formed on the uniformly charged photosensitive drum 10 by performing image exposure with the exposure optical system 12.

At the peripheral edge of the photosensitive drum 10, there is provided a developing device 13 as a developing means containing a two-component developer consisting of a negatively charged conductive toner and a magnetic carrier, and a magnet body. Reversal development is carried out by the developing sleeve 13a which holds the developer and rotates.

The developer is a toner having a weight average particle diameter of 3 to 10 μm in which a carrier having a ferrite core coated with an insulating resin around the core and a colorant such as a pigment or carbon black is added, a charge control agent and silica. , Titanium oxide, etc., and mixed so as to have a toner concentration of 5 to 10% by mass.
The layer is regulated to a layer thickness of 6 mm and conveyed to the developing area.

The gap between the developing sleeve 13a and the photoconductor drum 10 in the developing area is larger than the layer thickness of the developer, which is equal to 0.
An AC bias voltage obtained by superimposing an _AC voltage V _AC on a DC voltage V _DC is applied between the developing sleeve 13a and the photosensitive drum 10 with a thickness of 2 to 1.0 mm. Since charging of the toner is a DC voltage V _DC of the same polarity (negative), the toner given the opportunity to leave from the carrier by the AC voltage V _AC, the part of the high V _H absolute value of the potential from the DC voltage V _DC The toner amount corresponding to the potential difference adheres to the portion of V _L where the absolute value of the electric potential is low, and the image is visualized (reversal development).
Further, only the DC voltage V _DC may be applied between the developing sleeve 13a and the photosensitive drum 10. Contact development can also be used for development.

The intermediate transfer belt 14a facing each process unit PU has a volume resistivity of 10 ⁸ to 10 ¹² Ω · c.
m is an endless belt having a surface resistivity of 10 ⁸ to 10 ¹² Ω / □, and a conductive material is used for engineering plastics such as modified polyimide, thermosetting polyimide, ethylene tetrafluoroethylene copolymer, polyvinylidene fluoride, and nylon alloy. A two-layered seamless belt in which a fluorine coating having a thickness of 5 to 50 μm is preferably applied as a toner filming prevention layer on the outside of a dispersed semiconductive film substrate having a thickness of 0.1 to 1.0 mm. .
In addition to this, a semi-conductive rubber belt having a thickness of 0.5 to 2.0 mm in which a conductive material is dispersed in silicon rubber or urethane rubber can be used as the base of the intermediate transfer belt 14a. The intermediate transfer belt 14a includes a tension roller 14d, a driven roller 14e,
Tension roller 14i and backup roller 14f
And is stretched by being circumscribed outside, and at the time of image formation, the tension roller 14d is rotated by being driven by a drive motor (not shown),
At the transfer position for each color, the primary transfer roller 14c presses the intermediate transfer belt 14a against the photosensitive drum 10, and the intermediate transfer belt 14a is driven so as to circulate in the direction shown by the arrow in the figure.

A primary transfer roller 14c (primary transfer means), which is a transfer roller for each color, is provided so as to face the photoconductor drum 10 for each color with the intermediate transfer belt 14a interposed therebetween. A transfer area (no reference numeral) for each color is formed between the belt 14a and the photosensitive drum 10 for each color. By applying a primary transfer bias (no reference sign) composed of a DC voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) to the primary transfer roller 14c for each color, a transfer electric field is formed in the transfer area. , The toner images of the respective colors on the photoconductor drum 10 are transferred onto the intermediate transfer belt 14a.

As described above, the process unit PU
Since the toner images of Y, M, C, and K formed in (Y), PU (M), PU (C), and PU (K) are transferred and superposed on the intermediate transfer belt 14a as an image carrier. As is apparent, each process unit and the primary transfer roller 14c constitute a toner image forming means.

The charge eliminating means 14n for each color is preferably constituted by a corona discharger and removes electricity from the intermediate transfer belt 14a charged by the primary transfer roller 14c.

When image recording is started, the photoconductor drum 10 of the yellow (Y) process unit PU (Y) is rotated in the direction shown by the arrow by the start of the photoconductor drive motor (not shown), and at the same time, the Y scorotron charging is performed. The charging action of the container 11 starts applying the potential to the Y photoconductor drum 10.

After the Y photoconductor drum 10 is applied with a potential, the Y exposure optical system 12 starts image writing by an electric signal corresponding to the Y image data, and the image is written on the surface of the Y photoconductor drum 10. An electrostatic latent image corresponding to the Y image of the original image is formed.

The Y latent image is subjected to reversal development by the Y developing device 13 in a non-contact state, and a toner image is formed by Y toner according to the rotation of the Y photosensitive drum 10.

The Y toner image formed on the Y photoconductor drum 10 as the image forming body by the above image forming process is transferred by the Y primary transfer roller 14c in the Y transfer area (no reference numeral). The image is transferred onto the intermediate transfer belt 14a.

Next, the intermediate transfer belt 14a is synchronized with the Y toner image, and corresponds to the M image data formed on the M photosensitive drum 10 by the magenta (M) process unit PU (M). In the M transfer area (no reference numeral), the M toner image is formed by the M primary transfer roller 14c so that the M toner image is superposed on the Y toner image.

By the same process, the image data of C formed on the photosensitive drum 10 of C by the process unit PU (C) of cyan (C) is synchronized with the superimposed toner images of Y and M. C toner image corresponding to
In the transfer area (no reference numeral) of C, the primary transfer roller 1 of C
4c, the toner images of Y and M are superimposed and formed, and are synchronized with the superimposed toner images of Y, M, and C, and the black (K) process unit PU (K)
The K toner image corresponding to the K image data formed on the K photoconductor drum 10 by the K toner image in the K transfer area (no reference numeral) is transferred by the K primary transfer roller 14c. , C toner images are superimposed and formed, and Y, M, C and K superimposed color toner images are formed on the intermediate transfer belt 14a.

The transfer residual toner remaining on the peripheral surface of the photoconductor drum 10 for each color after transfer is cleaned by the photoconductor cleaning device 19 which is an image forming member cleaning means for each color.

The superposed toner images of Y, M, C and K four colors are collectively transferred to a heat resistant transfer belt 21 as a transfer body. Heat-resistant transfer belt 21 is endless 100-2
A heat-resistant surface layer having a low surface energy such as silicon rubber or fluororesin is provided on a support made of a heat-resistant resin film such as a polyimide film having a thickness of 00 μm,
Secondary transfer roller 22 (secondary transfer means), transfer fixing roller 23 constituting transfer fixing means, and tension roller 2
It is stretched around 2a and circulates in the direction of the arrow at the same peripheral speed as the intermediate transfer belt 14a. Intermediate transfer belt 14
a and the heat resistant transfer belt 21 are the backup roller 14
The secondary transfer area is formed by being nipped and conveyed between f and the secondary transfer roller 22, and the backup roller 14f is grounded.
In the present embodiment, a secondary transfer bias composed of a DC voltage having a polarity opposite to that of the toner (plus polarity in the present embodiment) is applied to the secondary transfer roller 22 (secondary transfer means) so that the color toner image is heat-resistant. It is efficiently transferred onto the transfer belt 21.

A heating roller 35 with a built-in heater is in pressure contact with the transfer fixing roller 23 with a built-in heater via the heat-resistant transfer belt 21. The toner image on the heat-resistant transfer belt 21 is transferred to the recording material P in contact with the recording material P while being heated and melted by the transfer fixing roller 23 and the heating roller 35. That is, the transfer fixing roller 23 and the heating roller 35 constitute a transfer fixing unit.

The recording material P is fed from the paper feed cassette 31 by the paper feed roller 32 and fed by the feed roller 33 through the paper feed path 30, or is fed from the manual paper feed section 60 by the manual paper feed roller 61. The recording material P fed through the paper feed path 30 by the conveying roller 33 is fed by the timing roller 34 in synchronization with the color toner image on the heat-resistant transfer belt 21, and the transfer fixing roller 2
The color toner image is transferred and fixed onto the recording material P at a transfer and fixing position (no reference numeral) where the heating roller 35 and the heating roller 35 face each other. At the transfer-fixing position, the surface temperature of the transfer-fixing roller 23 is set so that the toner on the heat-resistant transfer belt 21 is heated to the melting point or higher. As a result, the toner is fused to the recording material P, and good transfer and fixing are simultaneously performed. The heating roller 35 is preferably maintained at substantially the same temperature as the transfix roller 23. Heat resistant transfer belt 2
The transfer fixing position of No. 1 is a tension roller 14 that stretches the intermediate transfer belt 14a at one end of the intermediate transfer belt 14a.
The intermediate transfer belt 14a is disposed below the intermediate transfer belt 14a at a position distant from the intermediate transfer belt 14a.
Make sure that heating is suppressed. Further, as shown in FIG. 1, the recording material P is fed horizontally below the intermediate transfer belt 14a in a paper feed path 30 from a manual paper feed section 60 to a re-fixing device 50, which will be described later, through a conveyance roller 33. To be done. As a result, conveyance jam of the recording material is suppressed.

At the transfer fixing position using the heat resistant transfer belt 21, transfer is performed at a transfer rate of almost 100%, but a small amount of toner remaining on the heat resistant transfer belt 21 is cleaned by the cleaning means 100. Further, since the heat-resistant transfer belt 21 is heated by the transfer / fixing roller 23, on the downstream side of the transfer / fixing roller 23, a heat dissipation plate is brought into contact with the back surface of the belt or a fan is used to adjust the temperature. .

In the re-fixing device 50, the recording material P is passed between an upper roller 51 and a lower roller 52, which have a heater in a pressure contact state, and a gloss is imparted by applying heat and pressure. . A large amount of toner adheres to the color toner image, and the recording material P that has undergone the transfer and fixing process is in a state where the color image portion is in a raised state. Therefore, the re-fixing device 50 performs re-fixing mainly on pressure. The upper roller 51 is a hard roller having a metal roller surface provided with a resin layer for preventing toner filming, and the lower roller 52 is also the same hard roller as the upper roller 51 or a semi-hard roller covered with a rubber elastic layer having a high hardness. Gloss is imparted while squeezing the color toner portion in a raised state on the material P. The recording material P to which gloss has been imparted is ejected onto the paper ejection tray by the paper ejection roller 53.

Reference numerals 51a and 52a are cleaning rollers for removing trays attached to the upper roller 51 and the lower roller 52, and 51b is an oil roller for applying a releasing agent such as silicone oil to the upper roller 51.

The re-fixing device 50 described above has a switching means for reducing the pressing force between the upper roller 51 and the lower roller 52, and has a gloss / non-gloss switching button provided on an operation unit (not shown). The color image on the recording material P can be discharged as glossy or non-glossy by the operation.

Although the re-fixing device 50 has been described with respect to the embodiment in which the gloss imparting process is performed by applying heat and pressure, the so-called calendering process is performed in which the gloss imparting process is simply performed by applying only the pressure. It may be.

When double-sided image formation is selected by the image forming apparatus of the present embodiment, the recording material P having the color image on the surface after transfer and fixing is switched by the conveyance switching lever 41 and the re-fixing device 50. It is conveyed to the reversal conveyance path 40 without being conveyed to the reversal conveyance path 40 and is conveyed to the reversal conveyance roller 44 through the reversal path conveyance roller 42. The reverse conveyance roller 44 is configured so that the forward and reverse rotation directions can be switched, and the recording material P conveyed through the reverse conveyance path 40 by the reverse conveyance roller 44 has a sensor 45 at the rear end of the recording material P which is reversed. Transport detection lever 4 when detected by
3, the conveyance path is switched, the reversal conveyance roller 44 is reversed, the recording material P is reversed, and the recording material P is conveyed again into the paper feed path 30 through the reversal path conveyance roller 42 of the reversal conveyance path 40 and the timing roller. It is conveyed to 34.

The color toner image of the back side image on the intermediate transfer belt 14a is transferred to the heat resistant transfer belt 21 in the secondary transfer area, and the color toner image of the back side image on the heat resistant transfer belt 21 is synchronized with the timing roller. 34 is transferred and fixed on the back surface of the recording material P conveyed by 34 at the transfer fixing position,
The recording material P having the color images fixed on both sides is re-fixing device 50.
Will be fixed again. The re-fixing device 50 is provided on the side of the main body of the apparatus, which is separated from the intermediate transfer belt 14a, with respect to the transfer fixing position of the heat resistant transfer belt 21. As a result, heating of the intermediate transfer belt 14a due to heat from the refixing device 50 is suppressed. Further, by passing through the re-fixing device 50, gloss is simultaneously given to the color images on both the front and back sides.

As described above, a plurality of process units PU
For (Y), PU (M), PU (C), PU (K),
These process units PU arranged in parallel
The intermediate transfer belt 14a (belt-shaped intermediate transfer belt) is disposed below (Y), PU (M), PU (C), and PU (K), and the heat-resistant transfer belt 21 (transfer body) is used to transfer the recording material. The transfer fixing position to P is arranged below the one end of the intermediate transfer belt 14a, at a position apart from the intermediate transfer belt 14a, and the re-fixing device 50 is installed at the transfer fixing position of the heat resistant transfer belt 21. By providing it on the side of the main body of the apparatus, it is possible to provide a tandem type image forming apparatus having an optimal arrangement in which the intermediate transfer belt 14a is not deteriorated by heat from the transfer and fixing roller 23 and the re-fixing apparatus 50. , The difficulty of obtaining gloss of the color image formed by simultaneous transfer and fixing is eliminated, and the color image with excellent color reproduction and gloss is formed by simultaneous transfer and fixing with a high transfer rate. Provide an image forming apparatus of a tandem type becomes possible. Further, the recording material P is the intermediate transfer belt 1.
The recording material P is conveyed by being conveyed horizontally below 4a.
The transport jam is suppressed.

FIG. 2 is a diagram showing another example of the image forming apparatus according to the embodiment of the present invention. In the example shown in FIG. 2, a plurality of process units PU (Y), PU (M),
A heat-resistant transfer belt 2 as a transfer member for transferring a toner image from a photosensitive drum 10 as an image bearing member for PU (C) and PU (K).
A color toner image is formed on the heat resistant transfer belt 21A by being transferred onto the heat resistant transfer belt 21A and transferred onto the recording material P.

As described above, in this example, a toner image is formed on the photosensitive drum 10 as an image carrier by the toner image forming means including the scorotron charger 11, the exposure device 12 and the developing device 13.

Inside the endless heat-resistant transfer belt 21A,
A transfer / fixing roller 23 is provided to face the heating roller 35 with the heat-resistant transfer belt 21A interposed therebetween. The heat-resistant transfer belt 21 is formed on the belt plane formed by the heat-resistant transfer belt 21A.
Process unit PU from the upstream side in the rotation direction of A
(Y), PU (M), PU (C), and PU (K) are provided in this order, and in the same manner as described with reference to FIG. 1, each process unit has Y, M on the photosensitive drum 10. , C
And K toner images are formed. In the present embodiment, the toner image on each photoconductor drum 10 is applied with a primary transfer bias (no reference sign) composed of a DC voltage having a polarity opposite to the toner (plus polarity in the present embodiment).
By the next transfer roller 14c (primary transfer means), the heat-resistant transfer belt 21A is sequentially superposed and transferred, and then the color toner image on the heat-resistant transfer belt 21A is transferred and fixed on the recording material P by the action of heat and pressure. It

Each process unit includes the photosensitive drum 10.
When viewed from the transfer position (primary transfer position) of the toner image, the photosensitive drum 1 is viewed from the upstream side in the rotation direction of the photosensitive drum 10.
The photoconductor cleaning device 19 as an image forming member cleaning unit for cleaning the transfer residual toner on 0.
A scorotron charger 11 as a charging unit, an exposure optical system 12 as an image exposing unit, and a developing unit 13 as a developing unit.

At the periphery of the photosensitive drum 10, there is provided a developing device 13 as a developing means containing a two-component developer composed of a negatively charged toner and a magnetic carrier. Development sleeve 13 that holds and rotates
Reverse development is performed by a.

As a developer, a carrier having ferrite as a core and coated with an insulating resin around the core and a colorant such as pigment or carbon black are added, and a flat toner having a shape described later is added to a charge control agent, silica, titanium oxide or the like. And mixed so as to have a toner concentration of 5 to 10% by mass, and the toner is regulated to a layer thickness of 0.1 to 0.6 mm on the developing sleeve 13a and conveyed to the developing area.

The developing sleeve 13a and the photosensitive member in the developing area
The gap with the body drum 10 is larger than the layer thickness of the developer.
2 to 1.0 mm, the developing sleeve 13a and the photosensitive drum
DC voltage V between the ram 10_DCAC voltage V_ACSuperimpose
The applied AC bias voltage is applied. The charge of flat toner
DC voltage V_DCSince it has the same polarity (negative) as AC voltage V _AC
Was given the opportunity to leave the carrier by
The flat toner has a DC voltage V_DCV with higher absolute value of electric potential_H
V that has a low absolute value of electric potential_LPart of
A toner amount corresponding to the potential difference is attached and visualized (reversed image).
Image) Further, the developing sleeve 13a and the photosensitive drum 1
DC voltage V between 0 and_DCOnly may be applied. Note that
The development may be contact development.

Process units PU (Y), PU
The toner images formed on (M), PU (C), and PU (K) are transferred to the heat resistant transfer belt 2 by the primary transfer roller 14c.
The color toner image is transferred onto 1A and is overlaid to form a color toner image on the heat resistant transfer belt 21A. The formed color toner image is transferred and fixed on the recording material P. The heat-resistant transfer belt 21A after the transfer and fixing is cleaned by the cleaning unit 100. For the cleaning means 100,
A backup roller 100A having a built-in heat source is arranged to face it. The heat-resistant transfer belt 21A is heated by the backup roller 100A to soften the toner on the heat-resistant transfer belt 21A, thereby cleaning the cleaning unit 100.
Cleaning is promoted and good cleaning is performed.

<First Embodiment> FIG. 3 shows an example of a transfer member cleaning means in an image forming apparatus according to the first embodiment of the present invention.

The heat resistant transfer belt 21 that has passed through the heating roller 35 is cleaned by the cleaning means 100. The cleaning means 100 is a cleaning web 1.
01, a cylindrical support means 1 in which a doorway 102A is formed
02, the original winding shaft 103, and the winding shaft 104 are formed in the cleaning unit.

The cleaning web 101 has a thickness of 20 to
A 100 μm polyethylene terephthalate film, a polyimide film, a polyamide film or the like is used, and an unused cleaning web 101 is wound around a main winding shaft 103 to form a roll of the cleaning web 101.
It winds around 2 and is stretched around the winding shaft 104.

In image formation, the heat resistant transfer belt 21
Circulates as indicated by arrow X1, but the support means 10
2. The cleaning unit including the original winding shaft 103 and the winding shaft 104 is driven by the heat resistant transfer belt 21 and integrally rotates counterclockwise.

At the portion where the cleaning web 101 comes into contact with the heat resistant transfer belt 21, the heat resistant transfer belt 21 is heated by the transfer fixing roller 23. Therefore, the toner on the heat resistant transfer belt 21 is softened and deformed by the pressure contact between the cleaning web 101 and the heat resistant transfer belt 21, and the contact area of the toner with the cleaning web 101 increases. As a result, due to the difference between the surface energy of the surface layer made of a low surface energy material such as silicon rubber and fluororesin of the heat resistant transfer belt 21 and the surface energy of the film such as PET that constitutes the cleaning web 101, the heat resistant transfer belt 21. Transferred material such as transfer residual toner and paper dust adhered on the transfer material is transferred to the cleaning web 101 and the heat resistant transfer belt 21 is cleaned. In order to perform good cleaning, it is preferable to heat the toner above the melting point of the binder resin forming the toner. In cleaning, the cleaning unit is driven by the heat resistant transfer belt 21, so that the cleaning web 101 moves at substantially the same speed with respect to the heat resistant transfer belt 21. A drive unit may be provided in the cleaning unit, and the cleaning unit may be rotationally driven so that the cleaning web 101 moves at the same speed as the heat resistant transfer belt 21 during cleaning.

Since there is no cleaning action at the entrance / exit 102A of the supporting means 102, the entrance / exit 102A should not face the same part of the heat resistant transfer belt 21 when the cleaning unit rotates on the heat resistant transfer belt 21 during cleaning. It is desirable to configure. To this end, the circumference of the heat resistant transfer belt 21 and the supporting means 10
It is desirable to configure both such that the ratio with the perimeter of 2 is not equal to an integer.

Although the transfer material deposits are accumulated on the cleaning web 101, the take-up shaft 104 rotates and the unused cleaning web 101 is fed to the peripheral surface of the supporting means 102 to be renewed, whereby the supporting means 102 is renewed. The cleaning web 101 that goes around is always maintained so as to have a predetermined cleaning performance.

The winding shaft 104 is driven by a motor 106 as a driving means, and the motor 106 is a control means 10.
7, the cleaning web 101 that circulates around the supporting means 102 always maintains a predetermined cleaning performance.

As an updating mode, the winding shaft 104 is rotated at a low speed during the image forming process to perform winding.
The winding shaft 10 is regularly, for example, every time a fixed number of images are formed.
The cleaning web 101 is provided with a detection means for rotating the cleaning web 101 to detect dirt on the cleaning web 101.
When the dirt in the image reaches a predetermined level, the take-up shaft 104 is rotationally driven, or a jam occurs, the writing system including the generation of image data fails, and the image forming apparatus is stopped during the image formation. For example, when the image forming apparatus is stopped due to a predetermined cause, the cleaning web 101 is updated.

The above-described update mode may be used in combination with other update modes. In the case where the cleaning web 101 is updated in an update mode other than the above-described update mode, that is, when the image forming process is not being performed, the heat resistant transfer belt 21
Of the cleaning web, that is, at a speed of about 1/2 to 1/10 of the moving speed during the image forming process.
It is desirable to move 1 for winding and updating. If the moving speed at the time of updating is higher than 1/2 of the moving speed at the time of cleaning, winding may be disturbed and smooth updating may not be possible. If the moving speed at the time of updating is smaller than 1/10 of the moving speed at the time of cleaning, the updating will take a long time.

FIG. 4 shows another example of the cleaning means for the transfer member in the image forming apparatus according to the first embodiment of the present invention, showing an example of the cleaning means having the above-mentioned updating mode. When the contamination of the cleaning web 101 is detected by the optical sensor 105 as a detection means including a light projector and a light receiver, and when the contamination reaches a predetermined level, the control means 107 activates the motor 106 to rotationally drive the winding shaft 104. Then, the cleaning web 101 is updated.

When updating the cleaning web 101,
The cleaning unit is displaced by a separating means (not shown) such as a solenoid to move the cleaning web 10.
It is desirable to prevent the cleaning web 101 from rubbing the heat resistant transfer belt 21 by separating 1 from the heat resistant transfer belt 21. Alternatively, the cleaning web 10
It is desirable to disperse the portion of the heat resistant transfer belt 21 that is rubbed by the cleaning web 101 by moving the heat resistant transfer belt 21 when updating 1. Further, it is desirable that the cleaning unit is detachably provided so that a new cleaning unit can be mounted when the cleaning web 101 of the original winding shaft 103 is exhausted.

<Second Embodiment> FIG. 5 shows an example of a transfer member cleaning means in an image forming apparatus according to a second embodiment of the present invention.

The cleaning means includes a cleaning web 101, a winding shaft 202 around which the cleaning web 101 can be peeled off from the end, a peeling claw 203 as a removing means for peeling off the end of the cleaning web 101, and a peeling off. It has a cutter 204 and a guide 205 as a blade member which is an example of a cutting means for cutting the cleaning web 101.

In the image forming step, the roll of the cleaning web 101 is rotated counterclockwise as indicated by arrow X2 by being driven by the heat resistant transfer belt 21 which is cyclically moved as indicated by arrow X1. The cleaning web 101 is the winding shaft 20.
The end portion of the cleaning web 101 is in close contact with the roll because it is wound leftward (counterclockwise in the counterclockwise direction) on the second roll. In this way, the roll of the cleaning web 101 rotates in the winding direction, that is, in the left-hand winding direction, which is the direction in which the cleaning web 101 is directed toward the center of the roll. While the above condition is maintained, the roll is rotated and the heat resistant transfer belt 21 is cleaned.

When updating the cleaning web 101,
The winding shaft 202 is rotationally driven by the motor 106 in the direction opposite to the winding direction, that is, in the clockwise direction opposite to X2. By rotating the cleaning web 101 in the clockwise direction, the end portion of the cleaning web 101 is peeled off by the peeling claw 203 which constitutes a removing means. The end of the cleaning web 101 is cut to a predetermined length, that is, the circumference of the roll or more by the cutter 204, and the updating of the cleaning web 101 is completed. When the cleaning web 101 is updated, as shown in FIG. 5B, the roll composed of the cleaning web 101 is separated from the heat resistant transfer belt 21 by a separating means (not shown) such as a solenoid, or as shown in FIG. It is desirable to move the heat resistant transfer belt 21 as shown in FIG. The winding shaft 202 is detachably provided and is replaced with a new roll of the cleaning web 101 when the cleaning web 101 is used up.

FIG. 6 shows another example of the transfer member cleaning means in the second embodiment of the present invention.

In the example shown in FIG. 6, the cleaning web 1
01 indicates update units 101A and 10A as shown in FIG.
It is divided into 1B, ... And wound around the winding shaft 202. Each of the update units 101A, 101B, ...
When the cleaning web 101 has a length equal to or greater than the outer circumference of the roll, and the cleaning web 101 rotates during cleaning, that is, when the roll of the cleaning web 101 wound counterclockwise rotates counterclockwise. , The update units 101A, 101B, ... Are not separated from the roll of the cleaning web 101.

When updating the cleaning web 101,
The winding shaft 202 is driven to rotate clockwise by the motor 106. As a result, the renewal unit 101A is peeled off by the peeling claw 203, removed from the roll, and stored in the storage unit 20.
It is stored in 6. 205 is a guide. In this example, since the update units 101A, 101B, ... Are automatically removed by the peeling by the peeling claw 203 as described above, the cutter as in the example of FIG. 4 is unnecessary.

FIG. 7 shows still another example of the transfer member cleaning means in the second embodiment of the present invention.

In this example, the cleaning web 101 is divided into update units 101A, 101B, ... By cutting auxiliary lines CT such as perforations as shown in FIG. 7 (b).

When the cleaning web 101 is updated, the winding shaft 202 is rotationally driven in the clockwise direction to update the unit 101A for updating.
After being separated from the roll of the cleaning web 101, the winding shaft 202 and the holding roller 207 are locked in a stopped state and pulled by the pulling roller 208 serving as a cutting unit, so that the cleaning web 101 is cut at the cutting auxiliary line CT. To do.

8 and 9 show an example of the peeling claw used in the second embodiment. The end portion of the cleaning web 101 is attracted to the roll of the cleaning web 101 by its own adhesive force, but toner is removed from the cleaning web 101.
When accumulated in No. 01, the toner acts as an adhesive to strengthen the adhesion of the end portion of the cleaning web 101 to the roll. As a result, the peeling by the peeling claw 203 may not be performed smoothly.

FIG. 8 shows an example of measures against such a peeling defect. Reference numeral 203A denotes a peeling nail arranged inside the image width L, and 203B denotes a peeling nail arranged outside the image width L. Cleaning web 10 inside the image width L
The end of No. 1 is strongly adhered to the roll by the toner, but since the toner is not present outside the image width L, the end is relatively weakly adhered to the roll. Therefore,
The edge of the cleaning web 101 is reliably peeled off by the peeling claw 203B. Then, with respect to the cleaning web 101 whose end portion has been peeled to some extent, the peeling claw 2
Since 03A peels, the peeling is performed smoothly.

In order to ensure the peeling within the image width L, the peeling claw 203A is provided as shown in FIG.
It is desirable that the peeling claw 203A be arranged downstream of the winding 03B in the rotation direction of the winding shaft 202 at the time of updating so that the peeling claw 203A acts on the cleaning web 101 peeled by the peeling claw 203B.

In the example of FIG. 9, two peeling claws 203C constituting the removing means are provided, and these peeling claws 203C are
As shown in FIG. 9A, it is movably provided between a position D1 outside the image width L and a position D2 at the center.

As shown in FIG. 9A, the updating process of the cleaning web 101 is started with the peeling claw 203C at the position D1 outside the image width L, and the winding shaft 202 is rotated by a predetermined amount in the direction of the arrow. To drive. After the end portion of the cleaning web 101 has been peeled off, as shown in FIG. 9B, the peeling claw 203C is moved to the central portion D2 to expand the peeling range of the cleaning web 101 from both end portions to the central portion. The cleaning web 10 is driven by rotating the winding shaft 202.
A length obtained by adding a predetermined length to one circumference of 1 is peeled from the roll and cut.

[0100]

According to the first, second or fifth aspect of the present invention, since the drive means drives the main winding shaft of the cleaning web to update the cleaning web, the cleaning web can be automatically updated and the cleaning means can be used. Can always be maintained in good cleaning performance.
As a result, it is possible to realize an image forming apparatus in which the feature of the transfer member, which enables high-quality image formation, is fully utilized.

According to the third aspect of the present invention, since the entire surface of the transfer member is uniformly cleaned, it is possible to always obtain a good image without partial smearing of the image or uneven image.

According to the invention of claim 4 or 15, maintenance of the cleaning means becomes extremely easy.

According to the sixth aspect of the present invention, since the roll form is favorably maintained without providing a unit for maintaining the roll form of the cleaning web, a high cleaning performance can be obtained by the cleaning means having a simple structure.

According to the invention of claim 7, a high cleaning performance is always maintained with a simple structure.

According to the invention of claim 8, 9, 10 or 11, the structure for removing the used cleaning web is extremely simple.

According to the twelfth aspect of the invention, the used cleaning web can be removed from the roll of the cleaning web with a very simple structure.

According to the thirteenth or fourteenth aspect of the present invention, the used cleaning web can be reliably removed using the peeling claw.

According to the sixteenth aspect of the present invention, the cleaning web can be smoothly updated without taking a long time to update it.

According to the invention of claim 17, 18 or 19,
The cleaning performance of the cleaning means is automatically maintained always good.

According to the nineteenth aspect of the present invention, regardless of the operating condition of the apparatus, such as the apparatus in which the density of the formed image tends to be high or the density in the image tends to be low, good cleaning performance is always maintained and good. Image formation is performed.

According to the twentieth aspect of the present invention, the transfer performance of the transfer body can be favorably maintained in the case where a large amount of toner adheres to the transfer body due to the forced stop of the image forming process or the like.

According to the twenty-first aspect of the invention, the surface of the transfer body is prevented from being deformed or deteriorated by the cleaning web moving at the time of renewal, so that the transfer performance of the transfer body is always kept good.

According to the twenty-second aspect of the present invention, the surface of the transfer member is prevented from being partially deformed or deteriorated by the renewal of the cleaning web, and the transfer performance of the transfer member is maintained good.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing another example of the image forming apparatus according to the exemplary embodiment of the invention.

FIG. 3 is a diagram showing an example of a transfer member cleaning unit in the image forming apparatus according to the first embodiment of the present invention.

FIG. 4 is a diagram showing another example of a transfer member cleaning unit in the image forming apparatus according to the first embodiment of the present invention.

FIG. 5 is a diagram showing an example of a transfer member cleaning unit in an image forming apparatus according to a second embodiment of the present invention.

FIG. 6 is a diagram showing another example of a transfer member cleaning unit in the image forming apparatus according to the second embodiment of the present invention.

FIG. 7 is a diagram showing still another example of a transfer member cleaning unit in the image forming apparatus according to the second embodiment of the present invention.

FIG. 8 is a diagram showing an example of a peeling claw.

FIG. 9 is a diagram showing an example of a peeling claw.

[Explanation of symbols]

10 Photosensitive drum 14a Intermediate transfer belt 21, 21A heat resistant transfer belt 100 cleaning means 101 cleaning web 101A, 101B, 101C update unit 102 support means 102A entrance 103 original reel 104 winding shaft 105 Optical sensor 106 motor 107 control means 202 reel 203, 203A, 203B, 203C peeling claw 204 cutter

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2H033 AA01 AA08 BA25 BA27 BA51                       BA55 BA56 BA57 BB12 BB18                       BB28 BE09                 2H078 BB01 CC06 DD03 DD40 DD42                       DD51 DD57 DD64 DD73                 2H200 GA12 GA23 GA44 GA47 HA02                       HB12 JA02 JA28 JB10 JC03                       LB02 LB08 LB14 LB39 LB40                       NA02 PA11 PA12 PB22

Claims (22)

[Claims] 1. An image carrier, a toner image forming means for forming a toner image on the image carrier, a transfer body onto which the toner image on the image carrier is transferred, and a toner image on the transfer body. In an image forming apparatus including a transfer fixing unit that transfers and fixes particles to a recording material by heating and deforming the particles, and a cleaning unit that cleans the transfer body after the transfer, the cleaning unit is a cleaning web, an original cleaning web. A winding shaft, a winding shaft for the cleaning web, a main winding shaft and the winding shaft, and a port for the cleaning web to support the cleaning web between the original winding shaft and the winding shaft. The cleaning web on the supporting means includes a rotatable supporting means for contacting the transfer body and a driving means for driving the winding shaft. Performs more cleaning, by winding the cleaning web in the drive unit, the image forming apparatus characterized by updating the cleaning web. 2. The image forming apparatus according to claim 1, wherein in the step of cleaning the transfer body, the supporting unit moves in the same direction and at substantially the same speed with respect to the transfer body. . 3. The support means is configured such that the entrance and exit do not face the same position of the transfer body in the first circulation of the transfer body and the second circulation continuous to the first circulation. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. 4. The cleaning web, the original winding shaft,
The image forming apparatus according to any one of claims 1 to 3, wherein the winding shaft and the supporting unit are formed in a unit that can be attached to and detached from a main body of the image forming apparatus. 5. An image carrier, a toner image forming means for forming a toner image on the image carrier, a transfer body onto which the toner image on the image carrier is transferred, and a toner image on the transfer body. An image forming apparatus comprising: a transfer fixing unit that transfers and fixes particles to a recording material by heating and deforming the particles; and a cleaning unit that cleans the transfer body after transfer, wherein the cleaning unit is a cleaning web, a roll of the cleaning web. And a drive means for driving the outermost layer of the roll to contact the transfer body, and a drive means for driving the delivery shaft. The cleaning web of the outermost layer is used for cleaning, and the drive means An image forming apparatus that updates a cleaning web. 6. The image forming apparatus according to claim 5, wherein the driving unit rotationally drives the winding shaft in a direction opposite to that during cleaning. 7. The image forming apparatus according to claim 5, further comprising a removing unit that removes a portion of the used cleaning web from the roll. 8. The image forming apparatus according to claim 7, wherein the cleaning web includes a plurality of update units of the cleaning web having a predetermined length, and the removing unit removes the update unit from the roll. apparatus. 9. The image forming apparatus according to claim 7, further comprising cutting means for cutting the cleaning web into predetermined lengths. 10. The image forming apparatus according to claim 9, wherein a cutting auxiliary line is provided for each of the predetermined lengths of the cleaning web, and the cutting means cuts the cleaning web along the cutting auxiliary line. . 11. The image forming apparatus according to claim 9, wherein the cutting unit includes a blade member. 12. The image forming apparatus according to claim 7, wherein the removing unit has a peeling claw that peels off an end portion of the cleaning web. 13. The cleaning web has a width wider than an image width, and the peeling claw includes a peeling claw for peeling the cleaning web at a portion outside the image width. The image forming apparatus according to item 1. 14. The image forming apparatus according to claim 12, wherein the peeling claw moves in the width direction of the cleaning web to perform peeling. 15. The winding shaft is detachably attached to the main body of the image forming apparatus.
The image forming apparatus according to any one of 4 above. 16. The drive means moves the cleaning web at a speed of 1/2 to 1/10 of a moving speed of the cleaning web during cleaning of the transfer body. The image forming apparatus according to claim 1. 17. The image forming apparatus according to claim 1, wherein the driving unit updates the cleaning web by moving the cleaning web at a low speed during cleaning. 18. The image forming apparatus according to claim 1, further comprising a control unit that periodically operates the drive unit to update the cleaning web. 19. A detection means for detecting dirt on the cleaning web, and a control means for activating the drive means based on a dirt detection signal from the detection means to update the cleaning web. The image forming apparatus according to claim 1. 20. A control means for activating the drive means to update the cleaning web when the image forming apparatus is stopped due to a predetermined cause. 2. The image forming apparatus according to item 1. 21. When the cleaning web is updated,
The image forming apparatus according to claim 1, further comprising a separating unit that separates the transfer body and the cleaning web from each other. 22. The renewal of the cleaning web is performed while the transfer body and the cleaning web are in contact with each other and while the transfer body is moving. The image forming apparatus according to item.