JPH10268657A - Transfer and carrier device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove toner without providing a cleaning blade and also to reduce the number of components by providing a toner removing function at a mechanism for biased movement control. SOLUTION: The transfer and carrier unit of a printer device is provided with a cleaning roller 10 electrostatically attracting toner stuck on a transfer carrier belt 6. The shaft end part of the cleaning-roller 10 is provided with a biased movement detection ring 21 rotated by bring brought into contact with the transfer carrier belt 6 being in biased movement. Then, the rotational movement of the biased movement detection ring 21 caused by being brought into contact with the transfer carrier belt 6 being in biased movement is converted into the displacing movement of one shaft end part of the cleaning roller 10, so that a biased movement component is a reverse direction is imparted to the transfer carrier belt 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt driving apparatus, and more particularly to an improvement in a belt driving apparatus which is applied to a printer apparatus, a copying apparatus, etc., and which conveys a sheet while transferring a toner image on a photosensitive member onto the sheet.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 5-31224.
There is known an electrophotographic printer device as disclosed in Japanese Patent Application Publication No. 0-205. An example of this type of device will be described. 6 includes four image forming units a1 to a4 that form toner images of different colors from each other, and sequentially transfers the toner images from each of the image forming units a1 to a4 onto the recording paper b. FIG. 2 is a schematic diagram of a so-called full-color printer in which a full-color image can be obtained only by transporting a sheet b once.

More specifically, a plurality of rollers c1 to c4
A flat belt d having a dielectric layer on its surface is runnably stretched, and this flat belt d functions as a transfer conveyance belt. That is, the toner image is sequentially transferred in each of the image forming units a1 to a4 while the paper b is conveyed from right to left in the drawing as the transfer conveyance belt d travels. In the drawing, e1 to e4 are transfer rollers for nipping and transporting the sheet b between the image forming units a1 to a4. f1 and f2 are fixing rollers for fixing the toner image.

In this type of apparatus, it is necessary to remove the toner adhering to the surface of the transfer / transport belt d after transferring the toner image onto the sheet b so that the next transfer / transport operation can be performed satisfactorily. There is. As a configuration for removing the toner, as shown in FIG. 7, there is a cleaning blade g that comes into contact with the surface of the transfer / conveyance belt d to scrape off the toner. The cleaning blade g is made of, for example, urethane rubber formed in a plate shape, and the edge of the cleaning blade g is pressed against the surface of the transfer conveyance belt d at a predetermined pressure.

[0005]

However, there is the following problem in the case where the toner is removed by the cleaning blade g as described above.

First, the cleaning blade g has a stable cleaning operation while maintaining a low friction coefficient between the edge of the cleaning blade g and the surface of the transfer / conveying belt d by maintaining the friction coefficient therebetween. Is performed. However, when the toner is not interposed between the two, the friction coefficient becomes extremely high. That is, generally, most of the toner in the image forming units a1 to a4 is transferred to the paper b, and the toner not transferred remains in the image forming units a1 to a4. Therefore, in a normal state, the toner hardly adheres to the surface of the transfer conveyance belt d. That is, there is a possibility that the transfer conveyance belt d travels without toner between the cleaning blade g and the transfer conveyance belt d. In this case, as described above, the friction coefficient between the two d and g becomes extremely large, and the cleaning blade g
The possibility that "turning-up" or "damage" will occur at the edge of the "." In such a situation, the traveling of the transfer / conveying belt d is hindered, and a slippage occurs between the belt d and the rollers c1 to c4, which has a significant adverse effect on image formation on paper. Will be.

Further, in order to form an accurate image even when the friction coefficient increases, the rotational torque of the drive motor must be set high, which causes a problem that the size of the entire apparatus is increased. is there.

In this type of apparatus, it is necessary to stably move the transfer / conveyance belt d in order to form a good image. In particular, it is important to prevent the transfer conveyance belt d from moving in the width direction (hereinafter, referred to as deviation).

Heretofore, as a mechanism for preventing this deflection, a special deflection control roller has been provided, and by displacing one shaft end of the deflection control roller, a deflection component in the direction opposite to the initial deflection is provided. Is given to the belt. However, this deviation control roller has only this deviation prevention function.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is possible to remove toner without providing a conventional cleaning blade. It is another object of the present invention to reduce the number of components by providing the toner removing function.

[0011]

In order to achieve the above object, the present invention employs a cleaning roller capable of removing toner in place of a cleaning blade, and the shaft end of the cleaning roller is provided. The displacement correction function is exerted by displacing.

More specifically, the invention according to claim 1 is a transfer / conveying belt movably stretched over a plurality of rollers;
It is assumed that a transfer device includes a photoconductor arranged opposite to the transfer conveyance belt, and transfers a toner image formed on the surface of the photoconductor to the paper while conveying the paper on the transfer conveyance belt. A cleaning roller is provided, which is in contact with the transfer belt and rotates as the transfer belt runs, and removes toner attached to the surface of the belt. At least one shaft end of the cleaning roller can be displaced in a direction orthogonal to the axis thereof.
When the transfer conveyance belt is displaced, a roller end displacement means for displacing the shaft end of the cleaning roller in a direction in which the deviation of the belt is corrected is provided.

According to this specific matter, when the transfer conveyance belt runs, the paper is conveyed accordingly. The toner image formed on the surface of the photoreceptor arranged opposite to the transfer / conveying belt is transferred onto the sheet, and a predetermined image is formed. In such an image forming operation, when toner adheres to the transfer conveyance belt, the toner is removed by the cleaning roller. Further, when the transfer / conveying belt is deflected, one shaft end of the cleaning roller is displaced in a direction in which the belt deflection is corrected by the roller end displacing means. That is, the cleaning roller has a function of removing the toner from the transfer conveyance belt and a function of correcting the deviation of the transfer conveyance belt.

According to a second aspect of the present invention, the roller end displacement means is embodied. That is, at least one of the shaft ends of the cleaning roller is provided with a deviation detecting member rotatably supported independently of the cleaning roller. The transfer conveyance belt is deflected and contacts the deviation detection member,
When a rotational torque is applied to the deviation detecting member, the roller end displacement means converts the rotational movement into a movement in which the shaft end of the cleaning roller is displaced in a predetermined direction to correct the belt deviation. ing.

According to this specific matter, when the transfer conveyance belt is deflected and comes into contact with the deviation detecting member, a rotational torque acts on the deviation detecting member. Thus, the roller end displacement means converts the rotational movement of the deviation detecting member into a movement in which the shaft end of the cleaning roller is displaced in a predetermined direction. The displacement of the shaft end corrects the deviation of the transfer conveyance belt.

According to a third aspect of the present invention, a case where the deviation detecting member and the roller end displacement means are provided only at one shaft end of the cleaning roller is specified. In other words, the deviation detecting member is provided only on one shaft end of the cleaning roller, and a bias imparting means for previously displacing the transfer / transport belt on the side where the deviation detecting member is provided is provided.

According to this specific matter, an initial deviation toward the side where the deviation detecting member is provided is given to the traveling transfer / conveying belt by the offset imparting means. When the transfer conveyance belt comes into contact with the deviation detection member due to the initial deviation, the deviation of the transfer conveyance belt is corrected by the roller end displacement means, similarly to the operation according to the second aspect of the present invention. Therefore, in the present invention, the deviation of the transfer conveyance belt can be satisfactorily avoided only by providing the deviation detecting member and the roller end displacement means only at one shaft end of the cleaning roller, and the number of parts can be reduced. Can be achieved.

The invention according to claim 4 embodies the structure of the cleaning roller. The cleaning roller is made of a conductive material, and has a structure in which conductive fibers are exposed on the surface thereof.

According to this specific matter, for example, the toner can be negatively charged and the cleaning roller can be positively charged. This allows
The toner adhered to the transfer conveyance belt can be electrostatically attracted by the conductive fibers exposed on the surface of the cleaning roller, and the toner removing operation can be performed well. Further, since the conductive fibers come into contact with the transfer conveyance belt, the transfer conveyance belt is prevented from being damaged or worn.

[0020]

Next, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a case will be described in which the present invention is applied to a transfer and conveyance belt unit of an electrophotographic apparatus generally called a full-color printer.

As shown in FIG. 1, the main transfer / conveyance unit 1
Is configured such that a transfer conveyance belt 6 is stretched over a plurality of first to fourth rollers 2 to 5. The first roller 2 of the plurality of rollers 2 to 5 is a drive roller directly connected to a drive shaft of a drive motor (not shown). Each of the rollers 2 to 5 has a roller surface made of EPDM cross-linked rubber, so that a coefficient of friction between the rollers and the transfer conveyance belt 6 is maintained high. As another configuration, the roller surface may be made of resin, aluminum, stainless steel, or the like.

The transfer conveyance belt 6 has a dielectric layer formed on the surface thereof. That is, the transfer conveyance belt 6 functions as a transfer conveyance body that transfers the toner image onto the paper P. The base material of the transfer / conveying belt 6 is PET (polyester) or ETF having a high relative dielectric constant.
E (ethylene / tetrafluoroethylene copolymer), P
A resin film such as VDF (vinylidene fluoride resin) is used.

On the upper side of the transfer / conveyance belt 6, four image forming units 7a to 7d as photoreceptors are arranged to face each other in the belt running direction. These image forming units 7a to 7d form toner images of different colors (for example, yellow, magenta, cyan, and black).

In the drawing, reference numerals 8a to 8d are transfer rollers. These transfer rollers 8a to 8d are connected to the image forming unit 7a.
7d and 7d, respectively, and sandwiches the transfer conveyance belt 6 with the image forming units 7a to 7d. The transfer rollers 8a to 8d are given a charge (plus) opposite to the charge (minus) of the toner, so that the toner images of the image forming units 7a to 7d can be transferred onto the conveyed paper P. ing.

Reference numerals 9a and 9b denote fixing rollers for fixing the toner image transferred onto the sheet P.

As a feature of this embodiment, the second roller 3 and the third roller 3
A cleaning roller 10 is disposed between the roller 4 and the cleaning roller 10.

The base material 10b (see FIG. 4) of the cleaning roller 10 is made of a conductive material. In particular,
It is made of aluminum or stainless steel. As shown in FIG. 4, the conductive fiber 10c is exposed on the entire surface of the base material 10b.
The cleaning roller 10 is pressed against the transfer / transport belt 6 so that the leading end of the cleaning roller 10 contacts the surface of the transfer / transport belt 6. The conductive fiber 10c is made of a fiber such as nylon or polyester mixed with carbon black. The amount of exposure of the fiber is, for example, 2 mm to 8 mm.
Is set to Further, as shown in FIG. 5, a power supply 12A is connected to the cleaning roller 10 so that a charge (plus) opposite to that of the toner is given.

The cleaning roller 10 is in contact with a toner collecting roller 11. As shown in FIG. 3, the toner collecting roller 11 is linked to the shaft end of the cleaning roller 10 via a connecting member 15, and the dimension between the axes of the rollers 10, 11 is maintained at a predetermined dimension. It is supposed to be. That is, the toner collecting roller 1
1 is always in contact with the cleaning roller 10 at a constant pressure. A power supply 12B is connected to the toner collecting roller 11 so that a charge (minus) opposite to that of the cleaning roller 10 is applied (see FIG. 5).

The toner collecting roller 11 is provided with a scraping member 13. The scraping member 13 comes into contact with the outer peripheral surface of the toner collecting roller 11 and scrapes the toner attached to the surface of the rotating toner collecting roller 11.

The toner collecting roller 11 and the scraping member 13 are housed in a toner collecting box 14, and the toner scraped by the scraping member 14 is collected in the toner collecting box 14. .

An eccentricity correcting mechanism 20 for displacing the shaft end is provided at one shaft end of the cleaning roller 10 (the front shaft end in FIG. 2). Hereinafter, the deviation correcting mechanism 20 will be described.

As shown in FIGS. 2 and 3, at the shaft end of the cleaning roller 10, an eccentricity detecting ring 21 as an eccentricity detecting member is provided. This deflection detection ring 2
Reference numeral 1 denotes an insertion hole having a diameter substantially the same as that of the shaft end of the cleaning roller 10 at the center thereof. The shaft end of the cleaning roller 10 is inserted through the insertion hole. Thus, the deviation detecting ring 21 is supported on the shaft end coaxially with the cleaning roller 10 and rotatable independently of the cleaning roller 10. Also,
The deviation detection ring 21 is formed of a hard resin such as polyacetal or nylon having a high coefficient of friction with the transfer / transport belt 6 and excellent in abrasion resistance, or an elastic material such as urethane or rubber having a high degree of abrasion. I have. This deflection detection ring 21 has an inner end face which is
0 is disposed to face the end face of the roller body 10a. Further, the deviation detecting ring 21 is mounted on the riding surface 21.
a. The outer diameter of the portion of the riding surface 21a facing the end surface of the roller body 10a of the cleaning roller 10 is set to the same diameter as the outer diameter of the cleaning roller 10, and the diameter gradually increases as the distance from the end surface of the roller body 10a increases. Is inclined in such a manner that the diameter becomes larger. This allows the transfer / transport belt 6 to run on the running surface 21a due to the deviation of the belt.
A boss portion 2 is provided on the outer end surface of the deviation detecting ring 21.
1b is integrally formed.

The shaft end of the cleaning roller 10 is rotatably supported by a support member 22 and a tension applying member 23. The support member 22 includes the cleaning roller 1.
One end of a back tension spring 24 that urges one end of the zero upward is locked. The other end of the back tension spring 24 is locked to the body frame of the device.

The tension applying member 23 is fitted in a guide hole 25a formed in the main body frame 25 of the apparatus.
The guide hole 25a is a substantially rectangular opening extending in the horizontal direction. A spring support portion 25b for supporting one end of a tension spring 26 described later protrudes from one end of the guide hole 25a. On the other hand, a spring support portion 23 b for supporting one end of the tension spring 26 is also provided on one end surface of the tension applying member 23. A long hole 23a extending in the vertical direction is formed at the center of the tension applying member 23,
One end of the cleaning roller 10 is supported movably in the vertical direction. The tension applying member 23 is fitted in a guide hole 25a formed in the main body frame 25 of the apparatus, and is slidable in a horizontal direction (a direction orthogonal to the axis of the cleaning roller 10). A tension spring 26 is disposed between the tension applying member 23 and a spring supporting portion 25b formed at one end of the guide hole 25a, and the tension applying member 23 moves the tension applying member 23 rightward in FIG. Energizing force is being applied. This urging force acts so as to apply tension to the transfer conveyance belt 6.

One end of a detection cord 30 is attached to the boss 21b of the deflection detection ring 21. This detection string 3
The other end of the cleaning roller 10 is attached to the main body frame, and when the deflection detection ring 21 rotates, the detection string 30 is wound around the boss 21b, so that one end of the cleaning roller 10 is displaced downward. It has such a configuration.

With such a configuration, when the belt 6 rides on the riding surface 21a of the deviation detecting ring 21 due to the deviation (the direction of the arrow A in FIGS. 2 and 3) accompanying the traveling of the belt 6, the deviation Rotational torque acts on the detection ring 21 (see arrow B in FIG. 2). The rotation of the deflection detection ring 21 causes the detection cord 30 to be wound around the boss 21 b of the deflection detection ring 21. Since one end of the detection cord 30 is fixed to the main body frame, the shaft end of the cleaning roller 10 moves along the long hole 23a of the tension applying member 23 with this winding operation (see FIG. 2 and FIG. 2). FIG.
Arrow C). Thereby, the cleaning roller 10
Is inclined in a predetermined direction (for example, left side) toward the belt traveling direction. That is, the belt 6 wound along the cleaning roller 10 is moved in the direction of arrow D opposite to the direction of arrow A in FIGS. Accordingly, the deflection correcting mechanism 20 as a roller end displacement means for displacing the shaft end of the cleaning roller 10 in a direction orthogonal to the roller axis when a rotational torque acts on the displacement detection ring 21 is provided. It is configured. That is, when the shaft end on the right side of the cleaning roller 10 is displaced in the direction of arrow C in FIG. 2, a deviation component opposite to the initial deviation component (A direction component) is generated, and the initial deviation component is generated. The shaft end of the cleaning roller 10 is displaced until the pressures cancel each other.

As described above, the urging force of the back tension spring 24 acts on the shaft end of the cleaning roller 10 via the support member 22. For this reason, when the operation of the belt 6 riding on the deviation detecting ring 21 is eliminated, the shaft end of the cleaning roller 10 is returned to a predetermined position (the position shown in FIGS. 2 and 3) by the urging force of the back tension spring 24. It is supposed to be. With such a configuration, the cleaning roller 10
When the component in the reverse direction due to the displacement of the shaft end becomes larger than the initial component, the belt 6 starts to deflect in the reverse direction,
Since the amount of deviation detection ring 21 riding on ride-up surface 21a decreases, the rotational torque of deviation detection ring 21 also decreases, and as a result, the amount of displacement of the shaft end of cleaning roller 10 by back tension spring 24 also decreases. It is becoming.

When the belt is not in contact with the deviation detecting ring 21, the shaft end of the cleaning roller 10 is positioned at the center of the elongated hole 23 a of the tension applying member 23 by the urging force of the back tension spring 24. It is located above. At this position, the cleaning roller 10 is inclined leftward in the belt running direction with respect to the other rollers. That is, the cleaning roller 10 is inclined with respect to the other rollers such that the running belt 6 is deflected toward the deviation detection ring 21. That is, in this embodiment, the belt 6 is given an initial deviation toward the deviation detecting ring 21 by the inclined arrangement of the cleaning roller 10. This constitutes a bias imparting means.

As means for giving such an initial deviation, the circumferential length of the left and right ends of the belt may be changed, or at least one of the other rollers may be inclined to make the center of FIG. Deflection in the direction of arrow A can be performed.

As the supporting structure for the other shaft end of the cleaning roller 10, only the tension applying member 23 and the tension spring 26 described above are provided, and the same predetermined tension is applied to the transfer conveying belt 6 as described above. It has become.

Next, the transfer / transport operation of the present apparatus will be described. The first roller 2 is driven to rotate with the driving of the drive motor. Thereby, the transfer conveyance belt 6 travels, and the paper P is conveyed from right to left in FIG. The traveling position of the sheet P is inside both ends in the width direction of the transfer conveyance belt 6 and at a position closer to the belt center than the deviation detection ring 21. On the other hand, in each of the image forming units 7a to 7d, a toner image of each color is formed, and the toner images are sequentially transferred to the surface of the paper P being conveyed. As a result, a predetermined image is formed on the sheet P, and after the image is fixed by the fixing rollers 9a and 9b, the sheet is sent out from the apparatus.

In such a transport operation, as described above, the transfer roller 6 has the cleaning roller 10 inclined by the urging force of the back tension spring 24, so that the arrow A in FIGS.
Eccentrically. That is, the belt 6 is deflected toward the deflection detection ring 21 while traveling.

When the end of the belt 6 rides on the riding surface 21a of the deviation detecting ring 21 due to the deviation of the belt 6, the riding surface 21a of the belt 6 and the deviation detecting ring 21
The deflection detection ring 21 rotates (arrow B in FIG. 2) due to the frictional force acting between the detection string 30 and the detection string 30.
Is wound around the boss 21b of the deviation detecting ring 21.

By the winding operation of the detection cord 30, the shaft end of the cleaning roller 10 on the side where the deviation detection ring 21 is disposed is displaced in the direction of arrow C in FIGS. Due to this displacement, the belt 6 runs while being wound in the direction (D direction) opposite to the A direction, and the deviation of the belt 6 in the A direction is restricted. At the same time, the back tension spring 2
4 is extended and the spring reaction force is also increased.
0 and the balance of the back reaction force of the back tension spring 24, the cleaning roller 1
The displacement amount of zero is regulated, and the position of the end of the belt 6 is maintained at a certain fixed position.

Since the running of the belt 6 is performed in this manner, large deviation of the belt 6 is prevented.
The amount of deviation of the belt 6 can be suppressed to several mm or less. In other words, by automatically correcting the deviation while previating the belt 6 in one direction, the amount of deviation can be reduced to a small amount, and the belt 6 can run stably. Can be. Therefore, it is possible to form an accurate image on the sheet P.

On the other hand, the toner adhering to the surface of the transfer / conveying belt 6 in such an image forming operation is electrostatically attracted to the conductive fiber 10c of the cleaning roller 10 and thereafter collected by the toner collecting roller 11. The toner collected by the toner collecting roller 11 is scraped off by the scraping member 13 and collected by the toner collecting box 14. As a result, the toner adhered to the surface of the belt 6 is reliably removed, and the adverse effect on image formation due to the toner remaining on the surface of the belt 6 is avoided.

As described above, according to the configuration of the present embodiment, the cleaning roller 10 can have both the function of removing the toner adhered to the transfer conveyance belt 6 and the function of suppressing the deviation of the transfer conveyance belt 6. For this reason, the number of parts can be reduced, and the size of the entire apparatus can be reduced.

As for the function of removing the toner, the load applied to the transfer / transport belt 6 can be significantly reduced as compared with the conventional device using a cleaning blade, so that the transfer / transport belt 6 can be run stably. The occurrence of slippage between the belt 6 and the rollers 2 to 5 can be avoided, and image formation on paper can be performed accurately. Further, when a cleaning blade is employed, it is necessary to set the rotation torque of the drive motor high in order to perform accurate image formation. However, this is not necessary in the present embodiment. The size can be reduced.

Further, as a structure for exhibiting the deviation suppressing function, only the deviation detecting ring 21 and the deviation correcting mechanism 20 need be provided only at one shaft end of the cleaning roller 10, so that the number of parts can be reduced. Can be reduced.

Further, since the conductive fibers 10c of the cleaning roller 10 come into contact with the transfer / transport belt 6, the transfer / transport belt 6 can be prevented from being damaged or worn. Therefore, the life of the transfer conveyance belt 6 can be extended.

In this embodiment, the cleaning roller 10
The toner adsorbed on the toner is scraped off by the scraping member 13 via the toner collecting roller 11, but the toner collecting roller 11 is not always necessary.
The toner adsorbed on the surface may be directly scraped off.

In this embodiment, the case where the present invention is applied to a transfer / conveying belt unit of an electrophotographic apparatus called a full-color printer has been described. However, the present invention can be applied to other apparatuses such as a copying apparatus.

[0053]

As described above, according to the present invention, the following effects can be obtained. According to the first aspect of the present invention, while transporting the paper on the transfer transport belt,
A transfer roller that transfers a toner image formed on the surface of a photoreceptor to a sheet is provided with a cleaning roller that removes toner attached to the surface of the belt. Further, a roller end displacing means for displacing at least one shaft end of the cleaning roller in a direction in which the deviation of the belt is corrected is provided. Accordingly, the cleaning roller can be provided with a function of removing toner from the transfer conveyance belt and a function of correcting the deviation of the transfer conveyance belt. For this reason, the number of parts can be reduced, and the size of the entire apparatus can be reduced. In addition, the function of removing the toner can greatly reduce the load applied to the transfer / transport belt as compared with a conventional cleaning blade, so that the transfer / transport belt can run stably, and the transfer between the belt and the roller can be performed. The occurrence of slippage between them can be avoided, and image formation on paper can be performed accurately. In addition, when a cleaning blade is employed, the rotational torque of the drive motor needs to be set high in order to perform accurate image formation. The size can be reduced. Since these effects are exhibited, it is possible to improve the practicality of the transfer conveyance device.

According to the second aspect of the invention, at least one of the shaft ends of the cleaning roller is provided with an eccentricity detecting member. When a rotational torque is applied, the roller end displacement means displaces the shaft end of the cleaning roller using the rotational movement. Therefore, the operation of detecting the deviation and the operation of displacing the shaft end can be favorably performed, and the reliability of the deviation correcting function can be improved.

According to the third aspect of the present invention, the deviation detecting member and the roller end displacement means are provided only on one shaft end of the cleaning roller, and the transfer conveyance belt is provided in advance on the side where the deviation detecting member is provided. There is provided a bias imparting means for deviating. That is, the initial deviation is canceled by the roller end displacement means while giving the transfer conveyor belt an initial deviation toward the side where the deviation detecting member is provided. For this reason, only by providing a mechanism for correcting the eccentricity on only one shaft end of the cleaning roller, the eccentricity of the transfer conveyance belt can be satisfactorily avoided, and the number of components can be reduced.

According to the fourth aspect of the present invention, the cleaning roller is made of a conductive material, and the conductive fibers are exposed on the surface of the cleaning roller. For this reason, for example, by charging the toner negatively and conversely charging the cleaning roller positively, the toner adhering to the transfer conveyance belt is electrostatically charged on the conductive fibers exposed on the surface of the cleaning roller. The toner can be adsorbed, and the toner removing operation can be favorably performed. In addition, since the conductive fibers come into contact with the transfer / transport belt, the transfer / transport belt is prevented from being damaged or worn, and the life of the transfer / transport belt can be extended.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a transfer conveyance belt unit of a printer according to an embodiment.

FIG. 2 is a perspective view showing a support structure for one shaft end of a cleaning roller.

FIG. 3 is a front view showing a support structure for one shaft end of a cleaning roller.

FIG. 4 is a diagram illustrating a cleaning roller.

FIG. 5 is a schematic diagram illustrating a toner collection portion.

FIG. 6 is a diagram corresponding to FIG. 1 in a conventional example.

FIG. 7 is a diagram for explaining a toner removing operation by a cleaning blade.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transfer conveyance unit 2-5 roller 6 Transfer conveyance belt 7a-7d Image forming unit (photoreceptor) 10 Cleaning roller 20 Deviation correction mechanism (roller end displacement means) 21 Deviation detection ring (deviation detection member) P paper

Claims (4)

[Claims] An image forming apparatus comprising: a transfer conveyance belt movably stretched over a plurality of rollers; and a photoconductor arranged opposite to the transfer conveyance belt. In a transfer / transport device for transferring a toner image formed on the surface of a photoreceptor onto a sheet, the transfer / transport belt rotates while being in contact with the transfer / transport belt, and removes toner adhered to the surface of the belt. A cleaning roller, and at least one shaft end of the cleaning roller can be displaced in a direction orthogonal to the axis thereof. When the transfer conveyance belt is deviated, the deviation of the belt is corrected. And a roller end displacing means for displacing the shaft end of the cleaning roller in a predetermined direction. 2. The transfer conveyance device according to claim 1, wherein at least one shaft end of the cleaning roller is provided with a deviation detecting member rotatably supported independently of the cleaning roller. The displacement unit is configured to move the transfer end of the cleaning roller in a predetermined direction when the transfer conveyance belt is deflected and comes into contact with the deviation detection member and a rotational torque is applied to the deviation detection member. A transfer conveyance device characterized in that the deviation of the belt is corrected by converting the transfer to a transfer. 3. The transfer conveyance device according to claim 1, wherein the deviation detecting member is provided only on one shaft end of the cleaning roller, and the transfer conveyance belt is provided in advance on a side where the deviation detection member is provided. A transfer / conveying apparatus comprising a bias applying means for eccentricity. 4. The transfer / transport apparatus according to claim 1, wherein the cleaning roller is made of a conductive material, and a conductive fiber is exposed on a surface of the cleaning roller.