JP7003528B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus.

For example, in Patent Document 1, when a reverse bias is applied to a transfer means to transfer toner to an intermediate transfer belt, an elastic blade is used as a method for cleaning the back surface of the intermediate transfer belt, and a cleaning opposed roller and 1 are used on the back surface of the intermediate transfer belt. Disclosed is an image forming apparatus in which an intermediate transfer belt back surface cleaner is arranged between the next transfer rollers, and toner removed by the intermediate transfer belt back surface cleaner is collected by a collection unit arranged directly under the gravity direction of the intermediate transfer belt back surface cleaner. There is.

Japanese Unexamined Patent Publication No. 2008-170815

Here, if, for example, a blade is used as a member for cleaning the back surface of the transfer belt, foreign matter is generated by scraping the back surface of the transfer belt with the blade, and it becomes difficult to exert the cleaning performance of the blade. Further, when felt is used, the cleaning performance is deteriorated due to the accumulation of toner inside the felt.
An object of the present invention is to provide an image forming apparatus capable of suppressing deterioration of cleaning performance for cleaning a transfer member.

The invention according to claim 1 is a retainer that holds a toner image, a transfer member that transfers the toner image held by the retainer to a recording material, and a toner melting temperature or higher during an operation accompanied by transfer. A removing means in which a contact member having a temperature comes into contact with the inner peripheral surface of the transfer member to melt and remove the toner on the inner peripheral surface is provided , and the toner melting on the inner peripheral surface by the removing means is used as a recording material. It is an image forming apparatus that uses heat from a fixing means for fixing a toner image transferred to the toner image.
The invention according to claim 2 is the image forming apparatus according to claim 1 , wherein the removing means is located between the holding body and the fixing means.
The invention according to claim 3 has a retainer for holding a toner image, a transfer member for transferring the toner image held by the retainer to a recording material, and a toner melting temperature or higher during an operation accompanied by transfer. A removing means in which a contact member having a temperature comes into contact with the inner peripheral surface of the transfer member to melt and remove the toner on the inner peripheral surface is provided, and the transfer is performed on the toner melting on the inner peripheral surface by the removing means. An image forming apparatus that uses heat generated when the outer peripheral surface of a member comes into contact with a cleaning member that cleans the outer peripheral surface.
The invention according to claim 4 is the image forming apparatus according to claim 3 , wherein the cleaning member faces the contact member with the transfer member interposed therebetween.
The invention according to claim 5 is a holding body in which a toner image is held, a transfer member for transferring the toner image held in the holding body to a recording material, and a toner melting temperature or higher during an operation accompanied by transfer. A long-shaped peeling member for peeling the molten toner of the contact member is provided with a removing means in which a contact member having a temperature comes into contact with the inner peripheral surface of the transfer member and melts and removes the toner on the inner peripheral surface. , An image forming apparatus having a crown shape in which the central portion is longer than the end side portion.
The invention according to claim 6 is in contact with a holding body that holds a toner image, a transfer member that transfers the toner image held by the holding body to a recording material, and an inner peripheral surface of the transfer member. The contact member is provided with a removing means for melting and removing the toner on the inner peripheral surface when the temperature exceeds a predetermined temperature as the toner melting temperature due to the heat of the cleaning member for cleaning the outer peripheral surface of the transfer member. It is an image forming device.
The invention according to claim 7 is in contact with a holding body that holds a toner image, a transfer member that transfers the toner image held by the holding body to a recording material, and an inner peripheral surface of the transfer member. It is generated when the contact member, the first heat supply means for supplying the heat of the fixing means for fixing the toner image transferred to the recording material to the contact member, and the outer peripheral surface of the transfer member come into contact with the cleaning member. The toner on the inner peripheral surface is melted and then removed by the heat supplied by the second heat supply means for supplying heat to the contact member, the first heat supply means, and the second heat supply means. An image forming apparatus comprising a removing means.

According to claim 1, the configuration of the apparatus can be simplified as compared with the case where the heat of the fixing means is not used for melting the toner.
According to claim 2 , it is possible to suppress the thermal effect on the holding body as compared with the case where the removing means is not located between the holding body and the fixing means.
According to claim 3 , the configuration of the apparatus can be simplified as compared with the case where the heat generated between the outer peripheral surface of the transfer member and the contact member is not used for toner melting.
According to claim 4 , it is possible to increase the amount of heat generated between the outer peripheral surface of the transfer member and the contact member as compared with the case where the cleaning member sandwiches the transfer member and does not face the contact member.
According to claim 5 , it is possible to make the peeling action of the molten toner in the longitudinal direction of the contact member uniform as compared with the case where the peeling member does not have a crown shape.
According to the sixth aspect, it is possible to suppress the deterioration of the cleaning performance for cleaning the transfer member as compared with the case where the removing means is not provided.
According to the seventh aspect, it is possible to suppress the deterioration of the cleaning performance for cleaning the transfer member as compared with the case where the removing means is not provided.

It is an overall block diagram of an image forming apparatus. It is a figure explaining the relative positional relationship between a cleaning member and another device in an image forming apparatus. It is a figure explaining the structure of the cleaning device of an intermediate transfer belt. It is a bottom view explaining the roll and the cleaning plate of a cleaning device. It is a figure explaining the relative positional relationship between a cleaning device and a fixing device. It is a figure explaining the surface temperature of the roll of a cleaning apparatus, (a) shows the case where the surface temperature of a roll does not reach the melting temperature of toner, (b) shows the case where it reaches the melting temperature.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is an overall configuration diagram of the image forming apparatus 1.
The image forming apparatus 1 is a so-called tandem type color printer. The image forming apparatus 1 includes an image forming unit 10 as an example of the image forming means. The image forming unit 10 forms an image on paper P, which is an example of a recording material, based on the image data of each color.

Further, the image forming apparatus 1 is provided with a control unit 30 and an image processing unit 35. The control unit 30 controls each functional unit provided in the image forming apparatus 1. The image processing unit 35 performs image processing on image data from a personal computer (PC) 3, an image reading device 4, or the like.

The image forming unit 10 is provided with four image forming units 11Y, 11M, 11C, 11K (hereinafter, collectively referred to simply as "image forming unit 11") arranged in parallel at regular intervals. ing.
Each image forming unit 11 has the same configuration except for the toner stored in the developing device 15 (described later). Each image forming unit 11 forms a toner image (image) of yellow (Y), magenta (M), cyan (C), and black (K), respectively.

Each of the image forming units 11 includes a photoconductor drum 12 as an example of a holding body, a charger 200 for charging the photoconductor drum 12, and an LED print head (LPH) 300 for exposing the photoconductor drum 12. And are provided.
The photoconductor drum 12 is charged by the charger 200. Further, the photoconductor drum 12 is exposed by the LPH 300, and an electrostatic latent image is formed on the photoconductor drum 12.
Further, each image forming unit 11 is provided with a developer 15 for developing an electrostatic latent image formed on the photoconductor drum 12 and a cleaner (not shown) for cleaning the surface of the photoconductor drum 12. There is.

Further, the image forming unit 10 has an intermediate transfer belt 20 as an example of a transfer member to which each color toner image formed by the photoconductor drum 12 is transferred, and each color toner image formed by the photoconductor drum 12. A primary transfer roll 21 for sequentially transferring (primary transfer) to the intermediate transfer belt 20 is provided. In this embodiment, a cleaning device 50 for cleaning the intermediate transfer belt 20 is provided. The cleaning device 50 is an example of the removing means, and the details thereof will be described later.
Further, the image forming unit 10 has a secondary transfer roll 22 that collectively transfers (secondary transfer) the toner image transferred on the intermediate transfer belt 20 to the paper P, and the toner image transferred to the paper P on this paper. A fixing device 40 is provided as an example of the fixing means for fixing to P.

The fixing device 40 is provided with a fixing belt module 41 and a heating roll 46 provided with a heating source.
The fixing belt module 41 is arranged on the right side in the drawing of the paper transport path R1. The heating roll 46 is arranged on the left side in the drawing of the paper transport path R1. Further, the heating roll 46 is pressed against the fixing belt module 41.

The fixing belt module 41 includes a film-shaped fixing belt 411 that comes into contact with the paper P.
The fixing belt 411 is composed of, for example, a release layer located on the outermost layer and in contact with the paper P, an elastic layer located one inside of the release layer, and a base layer supporting the elastic layer.
Further, the fixing belt 411 is formed in an endless shape and circulates in the clockwise direction in the figure. Further, oil for lubrication is applied to the inner peripheral surface 411A of the fixing belt 411, and the sliding resistance between the heating source and the like described later and the fixing belt 411 is reduced.

The fixing belt 411 comes into contact with the paper P conveyed from the lower part in the drawing. Then, the portion of the fixing belt 411 that comes into contact with the paper P moves together with the paper P. Further, the fixing belt 411 sandwiches the paper P together with the heating roll 46, and pressurizes and heats the paper P.
The fixing belt module 41 may be provided with a heating source (described later) for heating the fixing belt 411 inside the fixing belt 411.

The heating roll 46 is arranged on the left side in the drawing of the paper transport path R1. The heating roll 46 is pressed against the outer peripheral surface 411B of the fixing belt 411 and pressurizes the paper P passing between the fixing belt 411 and the heating roll 46 (paper P passing through the paper transport path R1).
Further, the heating roll 46 is rotated in the counterclockwise direction in the figure by a motor (not shown). When the heating roll 46 rotates counterclockwise, the fixing belt 411 receives a driving force from the heating roll 46 and rotates clockwise.

Here, in the image forming apparatus 1 shown in FIG. 1, the intermediate transfer belt 20 is arranged in a substantially rectangular shape so as to be elongated in the left-right direction in the front view. The image forming unit 10 is located below the front view of the intermediate transfer belt 20, and the fixing device 40 is located above the front view of the intermediate transfer belt 20. Further, the paper transport path R1 is located on the right side of the front view of the most downstream image forming unit 11K, and is formed so as to extend in the vertical direction Y (see FIG. 2). That is, the paper transport path R1 is a path for transporting the paper P from the lower paper accommodating portion 1B to the upper fixing device 40 through the secondary transfer portion T.
The image forming apparatus 1 may be arranged in another configuration. For example, the image forming unit 10 is arranged on the upper side of the intermediate transfer belt 20 in the front view, the secondary transfer unit T and the fixing device 40 are arranged on the lower side of the front view, and the paper P is placed in either the left-right direction X (see FIG. 2). Transport to one side. An example in which the intermediate transfer belt 20 is arranged so as to be an inverted triangle when viewed from the front, and an example in which the intermediate transfer belt 20 is arranged so as to be substantially rectangular can be considered.

In the image forming apparatus 1, the image processing unit 35 performs image processing on the image data from the PC 3 and the image reading device 4, and the image data subjected to the image processing is supplied to each image forming unit 11.
Then, for example, in the black (K) color image forming unit 11K, the photoconductor drum 12 is charged by the charger 200 while rotating in the direction of arrow A, and emits light based on the image data transmitted from the image processing unit 35. It is exposed by the LPH300.

As a result, an electrostatic latent image relating to the black (K) color image is formed on the photoconductor drum 12. Then, the electrostatic latent image formed on the photoconductor drum 12 is developed by the developer 15, and a black (K) color toner image is formed on the photoconductor drum 12.
Similarly, in the image forming units 11Y, 11M, 11C, each color toner image of yellow (Y), magenta (M), and cyan (C) is formed.

Each color toner image formed by each image forming unit 11 is sequentially electrostatically attracted by the primary transfer roll 21 onto the intermediate transfer belt 20 moving in the direction of arrow B, and each color toner is placed on the intermediate transfer belt 20. A superposed toner image is formed.
The toner image formed on the intermediate transfer belt 20 is conveyed to a location (secondary transfer unit T) where the secondary transfer roll 22 is located as the intermediate transfer belt 20 moves. Then, the paper P is supplied from the paper accommodating unit 1B to the secondary transfer unit T at the timing when the toner image is conveyed to the secondary transfer unit T.

In the secondary transfer unit T, the toner images on the intermediate transfer belt 20 are collectively electrostatically transferred to the conveyed paper P by the transfer electric field formed by the secondary transfer roll 22.
After that, the paper P on which the toner image is electrostatically transferred is peeled off from the intermediate transfer belt 20 and conveyed to the fixing device 40.

In the fixing device 40, the paper P is sandwiched between the fixing belt module 41 and the heating roll 46. Specifically, the paper P is sandwiched between the fixing belt 411 circulating in the counterclockwise direction and the heating roll 46 rotating in the clockwise direction.
As a result, the paper P is pressurized and heated, and the toner image on the paper P is fixed on the paper P. Then, the paper P after the fixing is completed is conveyed to the paper loading unit 1E by the discharge roll 500.

Next, the relative positional relationship between the cleaning device 50 and other devices inside the image forming device 1 will be described.
FIG. 2 is a diagram illustrating the relative positional relationship between the cleaning device 50 and other devices inside the image forming device 1.
After explaining the position of the cleaning device 50 in the vertical direction Y, the position in the horizontal direction X will be described.
With respect to the vertical direction Y, as shown in FIG. 2, the cleaning device 50 is located above the image forming units 11Y, 11M, 11C, 11K and below the fixing device 40. The cleaning device 50 is located between the image forming unit 11 and the fixing device 40. In other words, the cleaning device 50 is located between the photoconductor drum 12 of the image forming unit 11 and the fixing device 40.
In the present embodiment, the position where the toner image is secondarily transferred to the paper P (see the secondary transfer roll 22) is the position where each color toner image of the photoconductor drum 12 is first transferred to the intermediate transfer belt 20 (see the secondary transfer roll 22). It is above the primary transfer roll 21). Further, the fixing device 40 is above the position where the primary transfer is performed.

When the intermediate transfer belt 20 is divided into a left region RL and a right region RR at the center position in the left-right direction with respect to the left-right direction X of the cleaning device 50, the cleaning device 50 is located in the right region RR, and the fixing device 40 is also located. Located in the right region RR. That is, the cleaning device 50 is located in the same right region RR as the fixing device 40. From another point of view, since the secondary transfer roll 22 is also located in the right region RR, the fixing device 40 is located in the same right region RR as the secondary transfer roll 22.
Further, since the left region RL is positively air-cooled by blowing air, the atmospheric temperature is relatively low. On the other hand, in the right region RR, air cooling by blowing air is not performed as much as in the left region RL, and since the fixing device 40 is provided, the atmospheric temperature is higher than that in the left region RL. No positive air is blown to the roll 53 of the cleaning device 50, which will be described later.
In addition, when the separation distance La (not shown) between the cleaning device 50 and the fixing device 40 is compared with the separation distance Lb (not shown) between the cleaning device 50 and the most upstream image forming unit 11Y, the separation distance La is separated. It is shorter than the distance Lb.

Further, as described above, by arranging the cleaning device 50 in the right region RR, it is possible to secure a long time until the portion of the intermediate transfer belt 20 that has passed through the cleaning device 50 reaches the most upstream image forming unit 11Y. This makes it possible to lower the temperature of the intermediate transfer belt 20 more reliably.

The cleaning device 50 for cleaning the intermediate transfer belt 20 described above will be described.
FIG. 3 is a diagram illustrating a configuration of a cleaning device 50 for the intermediate transfer belt 20.
The cleaning device 50 shown in FIG. 3 cleans both sides of the intermediate transfer belt 20. That is, the cleaning device 50 cleans the front surface 20a of the intermediate transfer belt 20 and also cleans the back surface 20b. Therefore, the cleaning device 50 includes a blade 51 for cleaning the surface 20a of the intermediate transfer belt 20, a recovery unit 52 for collecting deposits such as toner cleaned by the blade 51, and a back surface 20b of the intermediate transfer belt 20. It includes a roll 53 located on the side facing the blade 51, a cleaning plate 54 for cleaning the surface 20a of the roll 53, and a receiving plate 55 for receiving deposits such as toner dropped by cleaning by the cleaning plate 54. ..
The blade 51, the collecting portion 52, the roll 53, the cleaning plate 54, and the receiving plate 55 have at least the entire width in the width direction of the intermediate transfer belt 20 (the direction intersecting the moving direction of the intermediate transfer belt 20; the vertical direction on the paper surface in FIG. 3). It is provided over.
The roll 53 is an example of a contact member, the intermediate transfer belt 20 is an example of a transfer member, the back surface 20b of the intermediate transfer belt 20 is an example of an inner peripheral surface, and the cleaning device 50 is an example of a removing means. .. The blade 51 is an example of a cleaning member, and the cleaning plate 54 is an example of a peeling member.

The blade 51 of the cleaning device 50 slides on the surface 20a of the intermediate transfer belt 20 moving in one direction to remove the toner (residual toner) adhering to the surface 20a of the intermediate transfer belt 20. The surface 20a of the intermediate transfer belt 20 is a surface on which the toner image is transferred by the primary transfer roll 21. In the intermediate transfer belt 20, the front surface 20a is a smooth surface as compared with the back surface 20b, and the amount of scraping due to sliding is extremely smaller on the front surface 20a than on the back surface 20b. Further, for the blade 51, a material (for example, rubber or the like) is selected from which the blade 51 is scraped by sliding between the surface 20a of the intermediate transfer belt 20 and the blade 51.

The recovery unit 52 of the cleaning device 50 is located in a cover portion that partially opens to form a recovery space and a recovery space of the cover portion, and includes a screw auger or the like that sends out deposits in the width direction of the intermediate transfer belt 20 by rotation. It is provided with a delivery member. The deposits on the surface 20a of the intermediate transfer belt 20 are removed by the blade 51, and the removed deposits are recovered by the recovery unit 52.

The roll 53 of the cleaning device 50 is a member that receives a pressing force transmitted from the blade 51 via the intermediate transfer belt 20. The roll 53 follows the intermediate transfer belt 20 by coming into contact with the back surface 20b of the intermediate transfer belt 20. That is, the rotation of the roll 53 is performed by a drive source (not shown) of the intermediate transfer belt 20, and does not have a drive source only for driving the roll 53. Therefore, the roll 53 rotates when the intermediate transfer belt 20 rotates, and stops when the rotation of the intermediate transfer belt 20 stops. The roll 53 is made of metal, for example, SUS.
An example in which a drive source (not shown) different from the drive source of the intermediate transfer belt 20 is added and the roll 53 is driven by such a different drive source is also conceivable.

In addition, the roll 53 is arranged so as to apply tension to the intermediate transfer belt 20 (see FIG. 1 or 2), and the intermediate transfer belt 20 is bent by the roll 53.
Further, by configuring the roll 53 and the blade 51 to face each other with the intermediate transfer belt 20 interposed therebetween, the pressing force of the blade 51 can be increased, and the pressing force of the blade 51 pressing the intermediate transfer belt 20 can be increased. Become.

The cleaning plate 54 of the cleaning device 50 removes the toner adhering to the roll 53 by coming into contact with the outer peripheral surface of the rotating roll 53. The toner removed in this way falls by its own weight and is received by the receiving plate 55 of the cleaning device 50. For the cleaning plate 54, a relatively soft resin film such as PET is used.

Here, by cleaning the inside of the intermediate transfer belt 20, it is possible to suppress the occurrence of image defects due to the inside being contaminated with toner and the transfer bias becoming non-uniform. However, when the blade is applied to the back surface 20b of the intermediate transfer belt 20, the back surface 20b is scraped off, the drive load becomes large, and the belt becomes difficult to rotate. Further, when felt is applied to the back surface 20b of the intermediate transfer belt 20, if toner is accumulated in the hair, further cleaning cannot be performed, and there is a problem in cleaning maintainability. Further, since the cleaning roll has a low cleaning ability, it is difficult to use it for cleaning the back surface 20b.
Therefore, in the present embodiment, a configuration capable of more reliably cleaning the intermediate transfer belt 20 is adopted. More specifically, the roll 53 in contact with the back surface 20b of the intermediate transfer belt 20 has a surface temperature exceeding the melting temperature of the toner, and the toner remaining on the back surface 20b of the intermediate transfer belt 20 is melted and adhered to the roll 53. Before the toner adhering to the roll 53 cools and hardens, it is scraped off by the cleaning plate 54. As a result, it is possible to suppress wear of the back surface 20b of the intermediate transfer belt 20 while maintaining the cleaning performance of the cleaning device 50, and it is possible to reduce the drive load received by the drive source of the intermediate transfer belt 20. become.

More specifically, if the toner attached to the back surface 20b of the intermediate transfer belt 20 is not melted, it will pass through the roll 53 and it is difficult to attach it to the roll 53. However, when the front surface of the roll 53 becomes hot, toner is transferred or fixed to the roll 53 from the back surface 20b of the intermediate transfer belt 20, and the toner on the back surface 20b of the intermediate transfer belt 20 can be removed. When the toner exceeds the melting point, the toner becomes viscous, so that the molten toner on the roll 53 can be easily scraped off by the cleaning plate 54 and can be efficiently collected.

FIG. 4 is a bottom view illustrating the roll 53 and the cleaning plate 54 of the cleaning device 50. As described above, the roll 53 is a member facing the blade 51, and the cleaning plate 54 is a member for cleaning the surface of the roll 53.
As shown in FIG. 4, the roll 53 has a cylindrical shape or a cylindrical shape in which the outer diameter shape does not change at both ends and the central portion, and is not a crown shape. Further, the cleaning plate 54 has a shape in which the portion 54a in contact with the central portion 53a of the roll 53 and the portion 54b in contact with both end portions 53b have different shapes. That is, in the cleaning plate 54, the central portion 54a extends longer in the direction of the roll 53, and both end portions 54b are shorter in the direction of the roll 53 than the central portion 54a. The cleaning plate 54 has a so-called crown shape or fan shape formed in an arc shape having one side convex outward.

The reason why the cleaning plate 54 adopts such a shape is as follows. That is, the roll 53 is a longitudinal member having a long length with respect to the outer diameter, and although both end portions 54b are held by bearings, the central portion 54a is easily bent by receiving a load from the blade 51. Such deflection may make it difficult to remove the molten toner adhering to the roll 53.
Therefore, in the present embodiment, in consideration of the deflection of the roll 53, in order to suppress uneven removal by the cleaning plate 54, the cleaning plate 54 is provided so that the central portion 54a of the cleaning plate 54 extends long in the direction of the roll 53. Is forming. This makes it possible to make the peeling action of the molten toner in the longitudinal direction of the cleaning plate 54 uniform.

Next, the action of raising the roll 53 in contact with the back surface 20b of the intermediate transfer belt 20 to a temperature exceeding the toner melting temperature T3 (see FIG. 6) will be described.
FIG. 5 is a diagram for explaining the relative positional relationship between the cleaning device 50 and the fixing device 40, and for convenience of explanation, other members are shown by alternate long and short dash lines.
As shown in FIG. 5, the cleaning device 50 is located close to the secondary transfer roll 22 (secondary transfer unit T), and the fixing device 40 is also close to the secondary transfer roll 22 (secondary transfer unit T). And is located. In other words, the cleaning device 50 is located away from the secondary transfer unit T by a distance between the fixing device 40 and the secondary transfer unit T. From another point of view, the fixing device 40 is arranged so that the separation distance from the secondary transfer unit T and the separation distance from the cleaning device 50 are about the same.

In the fixing device 40, since the heating roll 46 includes a heating source for fixing the toner image of the paper P, the ambient temperature (atmospheric temperature) is increased. More specifically, the heating roll 46 provided with the heating source is located closer to the cleaning device 50. Therefore, the temperature in the vicinity of the cleaning device 50 increases due to heat radiation from the fixing device 40 or natural convection heat transfer. The surface temperature of the roll 53 in the cleaning device 50 is also increased by the heating source of the fixing device 40.
In addition, the amount of heat of the fixing device 40 heats the metal member that holds, for example, the blade 51 of the cleaning device 50, and the heat is transferred to the roll 53 through the blade 51 to raise the surface temperature of the roll 53. Contribute.

Here, when the temperature near the cleaning device 50 becomes equal to or higher than the toner melting temperature T3 due to the amount of heat of the fixing device 40, the toner of the intermediate transfer belt 20 melts and the toner removed by the blade 51 is removed by the screw auger. It becomes difficult to recover. In addition, when the temperature of the secondary transfer unit T becomes equal to or higher than the toner melting temperature T3 due to the heat of the fixing device 40, the toner image of the paper P may be partially melted before reaching the fixing device 40.
Therefore, it is better not to raise the surface temperature of the roll 53 in the cleaning device 50 to the toner melting temperature T3 only by the heating source of the fixing device 40.
On the other hand, in the case of reducing the influence of heat from the fixing device 40 on the cleaning device 50 and the secondary transfer unit T, it can be realized by setting the position of the fixing device 40 in the vertical direction Y on the upper side. The product height of the image forming apparatus 1 becomes high.

Further, in the cleaning device 50, frictional heat is generated when the blade 51 comes into contact with the surface 20a of the intermediate transfer belt 20 (self-heating). The frictional heat generated in this way is also transmitted to the roll 53 in contact with the back surface 20b of the intermediate transfer belt 20, and the surface temperature of the roll 53 can be raised. In addition to the role of removing the toner on the surface 20a of the intermediate transfer belt 20, the blade 51 also has a role of a sliding member that self-heats heat for use in raising the surface temperature of the roll 53.

In the present embodiment, the position of the cleaning device 50 with respect to the fixing device 40 is set so that the surface temperature of the roll 53 does not exceed the melting temperature T3 of the toner due to the heat of the fixing device 40 and is close to the melting temperature T3. is doing. Then, the surface of the roll 53, which has been heated by the heat of the fixing device 40 in this way, is further heated by the heat generated by the blade 51 to bring the toner to a melting temperature of T3 or higher.

This will be specifically described with reference to FIG.
6A and 6B are views for explaining the surface temperature of the roll 53 of the cleaning device 50, in which FIG. 6A shows a melting temperature T3 when the surface temperature of the roll 53 does not reach the melting temperature T3 of the toner. Show the case. For convenience of explanation, attention is paid only to the amount of heat from the fixing device 40 and the frictional heat between the blade 51 and the intermediate transfer belt 20.
As shown in FIG. 6A, when the cleaning device 50 is affected only by the amount of heat of the fixing device 40, the surface temperature of the roll 53 is raised to the atmospheric temperature T0 inside the image forming device 1 by the fixing device 40. The temperature T1 is obtained by adding the temperature Tf. Further, when the cleaning device 50 is affected only by the frictional heat between the blade 51 and the intermediate transfer belt 20, the surface temperature of the roll 53 becomes the temperature T2 obtained by adding the temperature Tb raised by the frictional heat to the atmospheric temperature T0. ..
Both the temperature T1 and the temperature T2 are lower than the melting temperature T3 of the toner (T1 <T3, T2 <T3). Therefore, the toner remaining on the back surface 20b of the intermediate transfer belt 20 cannot be melted and adhered to the roll 53.

Then, in the case shown in FIG. 6B, when the cleaning device 50 is affected by the heat amount of the fixing device 40 and the frictional heat between the blade 51 and the intermediate transfer belt 20, the surface temperature of the roll 53 is affected. , The temperature T4 is obtained by adding the temperature Tf raised by the fixing device 40 and the temperature Tb raised by the frictional heat to the ambient temperature T0.
The temperature T4 is higher than the toner melting temperature T3 (T4> T3). Therefore, the toner remaining on the back surface 20b of the intermediate transfer belt 20 can be melted and adhered to the roll 53.
In this way, the surface temperature of the roll 53 in the cleaning device 50 is set to a temperature equal to or higher than the toner melting temperature T3 due to the heat generated from the fixing device 40 and the friction between the blade 51 and the intermediate transfer belt 20. ing.
As an example of these temperatures, when the toner melting temperature T3 is 48 degrees and the atmospheric temperature T0 is 22 degrees, the temperature Tf raised by the fixing device 40 is 23 degrees, which is the temperature raised by frictional heat. Tb is 10 degrees. That is, the temperature T1 is 45 degrees, the temperature T2 is 32 degrees, and the temperature T4 is 55 degrees.

As described above, in the present embodiment, a plurality of heat supply means for raising the surface temperature of the roll 53 are provided. That is, in the present embodiment, the first heat supply means for supplying the heat amount of the fixing device 40 to the roll 53 is provided, and the frictional heat generated by the blade 51 continuing to be in contact with the moving intermediate transfer belt 20. Provide a second heat supply means to be supplied to the roll 53. In other words, the surface temperature of the roll 53 is set to the toner by utilizing the heat of the heating source of the fixing device 40 that heats a wide range and the frictional heat generated between the blade 51 and the intermediate transfer belt 20 generated in a narrow range. The temperature has risen above the melting temperature T3. Such heat supply may be performed by one or more of heat conduction, heat transfer or heat radiation.
As described above, in the present embodiment, no additional heating source for raising the surface temperature of the roll 53 is provided. This simplifies the internal configuration of the image forming apparatus 1.
As a supplement to the second heat supply means referred to here, the frictional heat between the blade 51 and the intermediate transfer belt 20 is the heat generated on the surface 20a side of the intermediate transfer belt 20, and the frictional heat on the surface 20a side. The temperature of the roll 53 in contact with the back surface 20b of the intermediate transfer belt 20 is raised.

Here, various modifications of the present embodiment can be considered.
For example, an example of providing an additional heating source (heater) for heating the surface of the roll 53 can be considered. In such an example, the constraint condition of the positional relationship with the fixing device 40 can be relaxed. The additional heating source may be arranged inside the roll 53 or may be arranged in the vicinity of the roll 53.
Further, there is an example in which an additional drive source (motor) for driving the roll 53 is provided so that a frictional force due to a rotation difference is generated on the roll 53 with respect to the intermediate transfer belt 20.

It is conceivable to add the heat supply means of such a modification instead of the heat supply means described in the present embodiment. That is, instead of the amount of heat of the fixing device 40 and / or the frictional heat between the blade 51 and the intermediate transfer belt 20, one or both of the above-mentioned amount of heat from the additional heating source and the frictional heat from the additional driving source is used. ..
Further, it is conceivable that the heat supply means of the modified example is provided together with the heat supply means described in the present embodiment. That is, in order to raise the surface temperature of the roll 53 to the melting temperature or higher, the heat of the fixing device 40 and the frictional heat between the blade 51 and the intermediate transfer belt 20 are used, and the heat of the above-mentioned additional heating source and the additional driving source are used. Utilize either or both of the frictional heat generated by.

Although the present invention has been described using the embodiments, the technical scope of the present invention is not limited to the above embodiments. It will be apparent to those skilled in the art that various modifications and alternative embodiments can be made without departing from the spirit and scope of the invention.

1 ... Image forming device, 12 ... Photoreceptor drum, 20 ... Intermediate transfer belt, 20b ... Back side, 40 ... Fixing device, 50 ... Cleaning device, 51 ... Blade, 53 ... Roll, P ... Paper

Claims (7)

A holder that holds the toner image and
A transfer member that transfers the toner image held by the holder to the recording material, and
A removing means in which a contact member having a temperature higher than the toner melting temperature during an operation accompanied by transfer comes into contact with the inner peripheral surface of the transfer member to melt and remove the toner on the inner peripheral surface.
Equipped with
An image forming apparatus in which heat from a fixing means for fixing a toner image transferred to a recording material is used for melting toner on the inner peripheral surface by the removing means . The image forming apparatus according to claim 1 , wherein the removing means is located between the holding body and the fixing means . A holder that holds the toner image and
A transfer member that transfers the toner image held by the holder to the recording material, and
A removing means in which a contact member having a temperature higher than the toner melting temperature during an operation accompanied by transfer comes into contact with the inner peripheral surface of the transfer member to melt and remove the toner on the inner peripheral surface.
Equipped with
An image forming apparatus in which heat generated by contacting an outer peripheral surface of the transfer member with a cleaning member for cleaning the outer peripheral surface is used for melting toner on the inner peripheral surface by the removing means. The image forming apparatus according to claim 3 , wherein the cleaning member faces the contact member with the transfer member interposed therebetween . A holder that holds the toner image and
A transfer member that transfers the toner image held by the holder to the recording material, and
A removing means in which a contact member having a temperature higher than the toner melting temperature during an operation accompanied by transfer comes into contact with the inner peripheral surface of the transfer member to melt and remove the toner on the inner peripheral surface.
Equipped with
The long-shaped peeling member for peeling the molten toner of the contact member is an image forming apparatus having a crown shape whose central portion is longer than the end side portion . A holder that holds the toner image and
A transfer member that transfers the toner image held by the holder to the recording material, and
The contact member in contact with the inner peripheral surface of the transfer member melts the toner on the inner peripheral surface when the temperature exceeds a predetermined temperature as the toner melting temperature due to the heat of the cleaning member that cleans the outer peripheral surface of the transfer member. And the removal means to remove
An image forming apparatus. A holder that holds the toner image and
A transfer member that transfers the toner image held by the holder to the recording material, and
A contact member that comes into contact with the inner peripheral surface of the transfer member ,
A first heat supply means for supplying the heat of the fixing means for fixing the toner image transferred to the recording material to the contact member,
A second heat supply means that supplies heat generated when the outer peripheral surface of the transfer member comes into contact with the cleaning member to the contact member.
A removing means for melting and then removing the toner on the inner peripheral surface with the heat supplied by the first heat supply means and the second heat supply means .
An image forming apparatus.

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