JP3175631B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to an image forming apparatus for forming a color image, and more particularly to an image forming apparatus in which a plurality of image carriers are arranged in parallel, and each color component image formed on each image carrier is intermediately transferred. The present invention relates to an improvement of a so-called tandem type image forming apparatus in which a color superimposed image on an intermediate transfer belt is once transferred onto a recording material after being once transferred to a belt.

[0002]

2. Description of the Related Art Conventionally, as an image forming apparatus of this type, for example, a plurality of photosensitive drums are arranged in parallel, and an intermediate transfer belt circulating along the arrangement direction of the photosensitive drums is provided. After each color component (for example, black, cyan, magenta, and yellow) image formed on the body drum is sequentially primary-transferred to the intermediate transfer belt, the color superimposed image on the intermediate transfer belt is secondary-transferred to paper (recording material). (Batch transfer), and an unfixed image is fixed on paper by a fixing device.

[0003]

However, in this type of image forming apparatus, since a paper cassette or the like is usually provided below the intermediate transfer belt, it is located near one end of the intermediate transfer belt in the longitudinal direction. Along with installing a secondary transfer device,
In many cases, a fixing device is juxtaposed on one side of the intermediate transfer belt in the longitudinal direction (Japanese Patent Laid-Open No. 8-15).
No. 948, JP-B 8-33685, JP-A-8-217
No. 302). In such an embodiment, since the device housing must have at least a unique space for the intermediate transfer belt and the fixing device, the width of the image forming device (corresponding to the longitudinal direction of the intermediate transfer belt) is correspondingly increased. Technical dimension) is unnecessarily bulky.

In addition, since a sufficiently long span between the secondary transfer device and the fixing device cannot be ensured, the sheet during the secondary transfer inevitably enters the fixing device. Under such circumstances, when using paper having a large heat capacity such as thick paper, it is necessary to maintain the fixing property by reducing the fixing speed of the fixing device. There is a technical problem that the speed itself has to be set low, and the productivity is reduced accordingly.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned technical problems, and it is an object of the present invention to maintain the driving stability of an intermediate transfer belt and the releasability of a recording material in a collective transfer area in an apparatus. It is an object of the present invention to provide an image forming apparatus that is compact (the width of the apparatus is reduced) and that can secure productivity in a mode in which a fixing device for thick paper or the like is decelerated.

[0006]

That is, the present invention provides:
As shown in FIG. 1, a plurality of image carriers 1 (for example, 1a to 1a) on which predetermined color component images are formed and
1d) and at least three or more support rolls 3 (for example, 3
a to 3c), which circulates along the arrangement direction of each image carrier 1 and temporarily transfers and holds each color component image on each image carrier 1; Each color held on the intermediate transfer belt 2 is provided at a position corresponding to the support roll 3c at a position most distant from a linear portion 2a extending substantially linearly along the arrangement direction of each image carrier 1 of the transfer belt 2 and held on the intermediate transfer belt 2. A collective transfer device 5 for collectively transferring the component images to the recording material 4, and a cleaning device 6 for removing residues on the intermediate transfer belt 2 after the collective transfer process to the recording material 4 by the collective transfer device 5 is completed. And a fixing device 7 for fixing each color component image collectively transferred onto the recording material 4, wherein the linear portion 2 a along the direction in which the image carriers 1 of the intermediate transfer belt 2 are arranged. Of the intermediate transfer belt 2 The transfer area of the collective transfer device 5 downstream toward displaced arrangement of the linear portion 2a from the center position Pc,
At least a part of the fixing device 7 is provided in a space below the inclined portion 2b of the intermediate transfer belt 2 located between the transfer area of the batch transfer device 5 and the support roll 3a at the upstream end in the moving direction of the linear portion 2a of the intermediate transfer belt 2. And the rush side end of the recording material 4 of the fixing device 7 is displaced toward the collective transfer device 5 with respect to the cleaning device 6 .
Transfer area and the moving direction of the linear portion 2a of the intermediate transfer belt 2
Intermediate transfer belt located between the flow end and the support roll 3b
2 is substantially perpendicular to the moving direction of the intermediate transfer belt 2.
A correction roll 8 for meandering control in the crossing direction is provided,
The upstream end in the moving direction of the linear portion 2a of the intermediate transfer belt 2
The correction roll 8 is connected to another support roll with respect to the support roll 3a.
It is characterized in that it is arranged at a distance from the nozzles 3b and 3c .

In such technical means, as the image carrier 1, any image carrier capable of carrying a visible image formed by various systems such as an electrophotographic system, an electrostatic recording system, and an ink jet recording system is used. The photoconductor, the dielectric, and the like may be appropriately selected, and the form may be a drum shape, a belt shape, or the like. Also, the number of the image carriers 1 may be arranged in a number corresponding to the number of the overlapping color components, or the number of the image carriers 1 smaller than the number of the overlapping color components may be arranged. Alternatively, at least one image carrier 1 may be shared as a carrier for a plurality of color component images.

Further, the support structure of the intermediate transfer belt 2 needs to be wound around at least three support rolls 3 (3a to 3c), and one of them, for example, the support roll 3a is driven. The intermediate transfer belt 2 may be circulated and rotated as a roll. In such a mode, from the viewpoint of preventing meandering in a direction substantially perpendicular to the moving direction of the intermediate transfer belt 2, one of the remaining support rolls 3b, 3c is replaced with a correction roll (steering roll) for controlling meandering. ), The transfer (primary transfer) from the image carrier 1 to the intermediate transfer belt 2 and the transfer (secondary transfer) to the recording material 4 by the collective transfer device 5 are good. From the viewpoint of maintaining the above-mentioned condition, it is preferable to provide a correction roll 8 separately from the support rolls 3b and 3c as shown by a virtual line in FIG. In this case, the intermediate transfer belt 2 is provided between the transfer area (the position corresponding to the support roll 3c) of the batch transfer device 5 and the support roll 3b at the downstream end in the moving direction of the linear portion 2a of the intermediate transfer belt 2. Of the upstream end in the moving direction of the portion 2a
The correction roll 8 is connected to another support roll with respect to the support roll 3a.
What is necessary is just to make it arrange | position apart from the nozzles 3b and 3c .

Furthermore, from the viewpoint of maintaining better transfer (secondary transfer) performance to the recording material 4 by the collective transfer device 5, it is located between the transfer area of the collective transfer device 5 and the correction roll 8. A contact member that contacts the inner surface of the intermediate transfer belt 2 is provided inside the intermediate transfer belt 2, and the movement of the meandering regulation of the intermediate transfer belt 2 by the correction roller 8 is directly transferred to the transfer area by the collective transfer device 5. It is preferable to suppress transmission. The contact member is not limited to a driven rotatable roll, but may be a plate-like member.

Further, in the embodiment using the correction roll 8, a support roll 3a composed of a driving roll is disposed at the upstream end of the linear portion 2a of the intermediate transfer belt 2 in the moving direction, and the intermediate transfer belt 3a is interposed on the support roll 3a. A support roll 3b composed of a driven roll toward the downstream side in the movement direction of the belt 2,
By arranging the correction roll 8 for meandering control in a direction substantially perpendicular to the moving direction of the intermediate transfer belt 2 and the collective transfer device 5 in sequence, an optimal stretching structure of the intermediate transfer belt 2 can be obtained. In such an embodiment, from the viewpoint of obtaining the driving stability of the intermediate transfer belt 2 and the reliability of the meandering regulation, the winding area of the intermediate transfer belt 2 is set with respect to the support roll 3a and the correction roll 8 composed of the driving rolls. It is preferable to stretch so that it becomes large.

The batch transfer device 5 is a transfer roll that sandwiches the intermediate transfer belt 2 using the support roll 3c as a counter electrode, as long as it forms a transfer electric field from the intermediate transfer belt 2 to the recording material 4. Or a corona discharger such as a corotron that charges the recording material 4 by corona discharge, but at least the transfer area of the collective transfer device 5 is the linear area 2a of the intermediate transfer belt 2. It is necessary to be displaced from the center position Pc to the downstream side in the moving direction of the linear portion 2a. However, the amount of the deviation may be appropriately selected.

It is important that the batch transfer device 5
To maintain good peeling performance of the recording material 4 in the transfer area due to the above. As will be described later, according to an experiment conducted by the present inventors, the distance between the surface of the intermediate transfer belt 2 located on the downstream side of the collective transfer device 5 and the surface of the guide / transport member of the recording material 4 after the collective transfer is determined. The opening angle is preferably set to 20 degrees or more, and the surface of the intermediate transfer belt 2 located downstream of the collective transfer device 5 and the extension surface of the intermediate transfer belt 2 located upstream of the collective transfer device 5 Is preferably set to 10 degrees or more.

In order to set such an opening angle, it can be appropriately selected according to the layout of the batch transfer device 5, specifically, the distance from the straight portion 2a and the amount of deviation of the straight portion 2a from the center position Pc. However, when a sufficient opening angle cannot be obtained due to the layout, for example, it is located between the transfer area by the batch transfer device 5 and the support roll 3a at the upstream end in the moving direction of the linear portion 2a of the intermediate transfer belt 2. On the surface side of the inclined portion 2b of the intermediate transfer belt 2, the inclined portion 2b is
What is necessary is just to contact and arrange | position the bending roll bent toward the a side.

Further, in consideration of space saving in the transport system of the recording material 4, the transport direction of the recording material 4 after passing through the batch transfer device 5 is substantially parallel to the linear portion 2 a of the intermediate transfer belt 2. It is preferable that the transfer path of the recording material 4 before and after the collective transfer device 5 has a mountain shape with the collective transfer position at the apex, especially when the detachability of the recording material 4 is emphasized.

Further, the collective transfer device 5 usually has a roll or the like that moves following the intermediate transfer belt 2, but in consideration of the driving stability of the collective transfer device 5, the collective transfer device 5 comes into contact with the intermediate transfer belt 2 and It is preferable to include a roll that is forcibly rotated by a driving device. In this case,
From the viewpoint of giving priority to the driving stability of the intermediate transfer belt 2, the driving device of the collective transfer device 5 includes an overload prevention mechanism in a driving force transmission mechanism between the collective transfer device 5 and a driving source. Is preferred.

The cleaning device 6 may be appropriately selected. However, from the viewpoint of maintaining good cleaning performance, it is preferable that the cleaning device 6 is provided at a portion facing the supporting roll composed of the driving roll, for example, 3a. Further, from the viewpoint of minimizing the load other than in the cleaning cycle, it is preferable that the cleaning device 6 is provided so as to be able to retract (contact and separate) from the intermediate transfer belt 2 freely. However, in a mode in which the intermediate transfer belt 2 is rotated a plurality of times in one color image forming cycle,
It is indispensable to provide the cleaning device 6 so as to be able to retract (contact and separate) from the intermediate transfer belt 2.

Here, as the cleaning device 6, it is preferable to employ a method having a high cleaning effect.
For example, a roller having a plurality of scraping members in contact with the surface of the intermediate transfer belt 2 and a plurality of backup rolls disposed on the back surface of the intermediate transfer belt 2 facing the scraping member is used. At this time, it goes without saying that, for example, the support roll 3a as a drive roll can be used as one of the backup rolls. In particular, in an embodiment in which a plurality of scraping members are configured to be retractable between a cleaning position where the scraping members come into contact with the intermediate transfer belt 2 and a retracted position where the plurality of scraping members are retracted from the intermediate transfer belt 2, If the span between them is set shorter than the span of the inter-image portion on the intermediate transfer belt 2, it becomes possible to simultaneously retract a plurality of scraping members.

In the case where the intermediate transfer belt 2 has a seam portion, if a blade is used as a scraping member, there is a concern that a situation (so-called banding) in which image residues accumulate on seam portion steps may occur. Therefore, it is preferable that the cleaning device 6 includes a scraper made of a fur brush that comes into contact with the surface of the intermediate transfer belt 2. In particular, in a type in which the intermediate transfer belt 2 has a seam portion, the intermediate transfer belt 2
It is preferable that a plurality of scraping members come into contact with the surface of the intermediate transfer belt 2, and the scraping member located on the upstream side in the moving direction of the intermediate transfer belt 2 is constituted by a fur brush that comes into contact with the surface of the intermediate transfer belt 2.

The fixing device 7 may be of a roll-pair type including a heating roll and a pressure roll,
Alternatively, a belt nip system including a heating roll and a pressure belt (or the reverse mode) may be used. The layout of the fixing device 7 may be such that at least a part of the fixing device 7 is disposed in a space below the inclined portion 2 b of the intermediate transfer belt 2. From the viewpoint of avoiding contamination of the recording material 4 due to the above, the rush side end of the recording material 4 of the fixing device 7 is displaced by a predetermined amount (d in the figure) toward the collective transfer device 5 with respect to the cleaning device 6. It is necessary to be. In particular, from the viewpoint of reliably avoiding the situation in which the image residue dropped on the recording material 4 is erroneously fixed by the fixing device 7, the cleaning device 6 is higher than the fixing material 7 in the fixing nip area. It is preferable to be arranged above the downstream side in the transport direction.

If emphasis is placed only on space saving, it is preferable to dispose the entire fixing device 7 in the space below the inclined portion 2b of the intermediate transfer belt 2, and to further install the cleaning device in the space below the inclined portion 2b. It is preferable to arrange the entire 6 as well.

In order to maintain the fixing property according to the type of the recording material 4 such as thick paper, it is necessary to make the speed of the fixing device 7 variable (for example, slow). For example, a speed control device may be provided that changes the conveyance speed of the recording material 4 after passing through the batch transfer device 5 according to the type of the recording material 4. In this case, for ease of speed control, for example, one or a plurality of recording material conveyance bodies (for example, a belt-shaped conveyance material) are provided between the collective transfer device 5 and the fixing device 7, and the speed control device is provided. A mode in which the speed of the fixing device 7 is changed from that of the intermediate transfer belt 2, and the speed of the recording material conveying body is changed to the intermediate transfer belt 2.
It is preferable that the fixing device 7 can be controlled independently of the fixing device 7. Further, in order to easily cope with the recording material 4 of the maximum size that can be conveyed by the variable fixing speed method, the maximum conveyable distance between the transfer area by the collective transfer device 5 and the fixing nip area of the fixing device 7 is set. It is preferable to set the length longer than the size of the recording material 4.

Incidentally, in a mode in which the distance between the transfer area by the collective transfer device 5 and the fixing nip area of the fixing device 7 cannot be set longer than the maximum sized recording material 4 that can be conveyed, the collective transfer device 5 Normal control is performed on the small-sized recording material 4 within the distance between the transfer area and the fixing nip area of the fixing device 7, and the transfer area of the batch transfer device 5 and the fixing device 7 are controlled.
For a large-sized recording material 4 exceeding the distance between the fixing nip area and the intermediate transfer belt 2, for example, the intermediate transfer belt 2 is dummy-rotated once after the primary transfer process is completed. Should be matched.

When the moisture content of the recording material 4 or the superimposed image is high, if the fixing device 7 rapidly heats and fixes the image, there is a concern that the superimposed image may be scattered locally. From the viewpoint of effectively avoiding such a concern, an auxiliary heat supply device for supplying heat to the recording material 4 in an auxiliary manner is provided near the conveyance path of the recording material 4 reaching the fixing device 7. Is preferred.

Next, the operation of the above technical means will be described. In FIG. 1, the transfer by the collective transfer device 5 from the central position Pc in the moving direction of the intermediate transfer belt 2 to the downstream side of the linear portion 2a of the linear portion 2a of the intermediate transfer belt 2 along the direction in which the image carriers 1 are arranged. The zones are offset. At this time, the support roller 3 at the upstream end in the moving direction of the transfer area by the batch transfer device 5 and the linear portion 2a of the intermediate transfer belt 2
a, a wide space is secured below the inclined portion 2b of the intermediate transfer belt 2 located therebetween, and the distance to the end of the inclined portion 2b is given as a sufficiently long one. And
A fixing device 7 is provided in a space below the inclined portion 2b of the intermediate transfer belt 2.
Of the intermediate transfer belt 2
No space is required for the entire fixing device 7 in the side space of the intermediate transfer belt 2 along the moving direction of the intermediate transfer belt 2, and the distance between the collective transfer device 5 and the fixing device 7 is sufficiently ensured. You. Further, since the entry end of the recording material 4 of the fixing device 7 is displaced toward the collective transfer device 5 with respect to the cleaning device 6, even if the image residue drops from the cleaning device 6, the image is not removed. The residue does not fall directly onto the recording material 4 before fixing. Further, since the superimposed image transferred on the intermediate transfer belt 2 reaches the transfer area by the batch transfer device 5 in a relatively short time, image disorder during the conveyance process by the intermediate transfer belt 2 is small. Further, the correction roll 8 is provided between the transfer area of the batch transfer device 5 and the intermediate transfer bell.
And the supporting roll 3b at the downstream end in the moving direction of the linear portion 2a of the
Provided inside the intermediate transfer belt 2 located between
The upstream end in the moving direction of the linear portion 2a of the intermediate transfer belt 2
The support roll 3a is higher than the other support rolls 3b and 3c.
The intermediate transfer belt 2 is disposed at a distance from the
Controls meandering in orthogonal directions.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the accompanying drawings. Embodiment 1 FIG. 2 shows Embodiment 1 of an image forming apparatus to which the present invention is applied.
Is shown. In the figure, an image forming apparatus is an image forming unit 20 (20a to 20d) that forms four color components (black, yellow, magenta, and cyan in this embodiment) image (toner image) by, for example, an electrophotographic method. When,
An intermediate transfer belt 30 for sequentially transferring (primary transfer) and holding each color component image formed by each image forming unit 20;
A collective transfer device 50 for collectively transferring (secondarily transferring) the superimposed image transferred on the intermediate transfer belt 30 to a sheet (recording material) 100; a belt cleaner 60 for removing residual toner on the intermediate transfer belt 30; Transfer the transferred image to paper 10
And a fixing device 70 for fixing the image on the surface of the image forming apparatus.
According to the present embodiment, each color component toner image formed by each image forming unit 20 is sequentially transferred to the intermediate transfer belt 30, and the superimposed toner image on the intermediate transfer belt 30 is
After the batch transfer, the toner is fixed by the fixing device 70, and the residual toner on the intermediate transfer belt 30 is removed by the belt cleaner 60.

In the present embodiment, each of the image forming units 20 (20a to 20d)
(Specifically, 21 a to 21 d), and a charging device 22 (specifically, 22 a to 22 d) such as a corotron to which the photosensitive drum 21 is charged is provided around each photosensitive drum 21.
d) an exposure device 23 (specifically, 23 a to 23 d) such as a laser scanning device in which an electrostatic latent image is written on the charged photosensitive drum 21, and an electrostatic device written on the photosensitive drum 21. Developing device 24 in which the latent image is developed with each color component toner
(Specifically, 24a to 24d) and a primary transfer device 25 (specifically, 25a to 25d) such as a transfer roll for transferring the toner image on the photosensitive drum 21 to the intermediate transfer belt 30.
d) and a drum cleaner 26 (specifically, 26a to 26d) for removing the residual toner on the photosensitive drum 21.

The intermediate transfer belt 30 is stretched over a plurality of (five in this embodiment) support rolls 31 to 35, and each photosensitive drum 2 is supported between the support rolls 31 and 32.
1 has a linear portion 30a extending substantially linearly along the arrangement direction, and the support roll 3
4 at the lowermost position, and further, support rolls 32,
The support roll 3 is formed so that the angle between 33 and 34 is acute.
3 is disposed outside of a straight line connecting the support rolls 32 and 34, and the support rolls 35 and 31 are formed so that the angle formed by the support rolls 34, 35 and 31 is obtuse (in the present embodiment, nearly 180 degrees). Are arranged slightly outside the straight line connecting the support rolls 34 and 31. In the present embodiment, as shown in FIGS. 2 and 3,
The support roll 31 is used as a drive roll driven by a belt drive motor 36, the support rolls 32 and 35 are used as driven rolls, and the support roll 33 is moved in a direction substantially orthogonal to the moving direction of the intermediate transfer belt 30. It is used as a meandering control correction roll (steering roll: provided so as to be tiltable with one end in the axial direction as a fulcrum).
Used as a backup roll.

Further, in the present embodiment, the support roll 34
Is the longitudinal center P of the linear portion 30a of the intermediate transfer belt 30.
A predetermined amount (FIG. 3)
(Indicated by middle g), and the intermediate transfer belt 30
Angle α around the drive roll 31 and the correction roll 3
3 is adjusted so that the winding angle β is sufficiently large. Therefore, the driving of the intermediate transfer belt 30 is stabilized, and the meandering restricting operation by the correction roll 33 is also stably performed. In particular, in the present embodiment, since the linear portion 30a of the intermediate transfer belt 30 is formed on the surface between the drive roll 31 and the driven roll 32, even if the meandering regulation by the correction roll 33 is performed, the intermediate transfer Belt 3
The meandering control operation of 0 does not directly affect the linear portion 30a. For this reason, the primary transfer operation sequentially performed in the linear portion 30a is performed stably, and there is no concern that the primary transfer operation is directly disturbed by the meandering regulation operation of the intermediate transfer belt 30. Reference numerals 37 and 38 denote a charging device for polarity adjustment such as a corotron and a counter electrode for aligning the polarity of each color toner image on the intermediate transfer belt 30, and 39 denotes an intermediate transfer belt 30 before the cleaning process by the belt cleaner 60. This is, for example, a static eliminator composed of a corotron pair configuration for removing the above residual charges.

In the present embodiment, as shown in FIG. 4, the batch transfer device 50 includes a transfer roll 51 which is retractably provided on the surface side of the intermediate transfer belt 30 and is grounded, and A backup roll 52 (also serving as the support roll 34 in the present embodiment) provided at a portion opposing the backup roll 51
2 and a bias roll 53 to which a predetermined DC bias 54 is applied. In particular,
In the present embodiment, the transfer roll 51 is moved with respect to a line connecting the point at which the intermediate transfer belt 30 contacts the upstream side of the backup roll 52 and the center of the backup roll 52 in a state where the transfer roll 51 is not pressed. A straight line connecting the centers of the rolls 52 is displaced by γ (about 10 degrees in the present embodiment) on the upstream side in the moving direction of the intermediate transfer belt 30.

In the present embodiment, the paper 100 enters the transfer area (corresponding to the nip area between the transfer roll 51 and the backup roll 52) of the batch transfer apparatus 50 through the chute 101. In the present embodiment, the chute 101 is inclined at an angle θ1 (for example, about 12 degrees) with respect to the surface of the intermediate transfer belt 30 located on the upstream side of the collective transfer device 50.

The angle θ between the surface of the intermediate transfer belt 30 located on the downstream side of the collective transfer device 50 and the paper guide plate 102 also provided on the downstream side of the collective transfer device 50, Investigation of the relationship between the number of sheets and the number of sheets having poor peeling with respect to the number of sheets) yielded the results shown in FIG. In this experiment, the outer diameter of each of the transfer roll 51 and the backup roll 52 was 28 mm. According to the results shown in FIG. 5, it was confirmed that there was almost no paper peeling defect when θ was 20 degrees or more. To further describe this point, in the present embodiment, the extension of the surface of the intermediate transfer belt 30 located on the upstream side of the collective transfer device 50 and the paper guide plate 102 provided on the downstream side of the collective transfer device 50 are described. Since the angle θ1 substantially corresponds to 10 degrees, which is the deviation angle of the transfer roll 51, the angle θ1 is located on the extension surface of the intermediate transfer belt 30 located on the upstream side of the collective transfer device 50 and on the downstream side of the collective transfer device 50. If the angle θ2 with respect to the surface of the intermediate transfer belt 30 is 10 degrees or more, it can be said that almost no sheet peeling failure occurs.

The upper limit of θ (or θ 2) is determined by, for example, the minimum winding angle of the drive roll 31 (the minimum winding angle required to prevent occurrence of slippage between the drive roll 31 and the intermediate transfer belt 30). ) Is restricted by α. The present inventors have examined the relationship between the diameter of the driving roll 31 and the minimum winding angle α, and have obtained the results shown in FIG. In this experiment, the driving roll 3
As No. 1, a surface urethane coat roll was used. According to this, it is understood that, when the drive roll 31 having a diameter of φ20 to φ30 is used, a winding angle α of about 140 degrees is necessary. Therefore, it is understood that the upper limit value of θ (or θ2) is about 50 degrees (or 40 degrees).

In particular, in the present embodiment, the batch transfer device 5
0, the conveyance direction of the sheet 100 is substantially parallel to the linear portion 30 a of the intermediate transfer belt 30, so that the space of the sheet conveyance path does not needlessly increase, and Since the conveyance path of the paper 100 has a mountain shape with the transfer area at the top, the paper 100
Is easily realized.

Further, the span x between the transfer area of the collective transfer device 50 and the sheet guide plate 102 also affects the sheet releasability. The present inventors have examined the relationship between the span x and the rate of defective sheet peeling, and have obtained the results shown in FIG. According to the figure, if the span x is within 10 mm,
It was confirmed that paper peeling failure did not occur.

In the present embodiment, the belt cleaner 60 is retractably provided at a location corresponding to the drive roll 31 and the support roll 35, and a conductive fur brush 61 is provided at a location corresponding to the support roll 35. Are disposed, and two blades 62 and 63 are disposed at a position corresponding to the drive roll 31. In addition, fur brush 61
A brush cleaning roll 64 is disposed in contact with the brush cleaning roll 64.
Are arranged in contact. Further, in the present embodiment, the belt cleaner 60 is retracted to the retracted position at the time of maintenance or the like. In the present embodiment, the inclined portion 30b of the intermediate transfer belt 30 located between the transfer area of the collective transfer device 50 and the drive roll 31 has a sufficiently long dimension. The length of the fur brush 61 and the blades 62, 6 can be secured to a certain extent.
The cleaning process is performed separately at two locations 3.
Therefore, it is possible to set the pressure contact force on the intermediate transfer belt 30 smaller than in a case where the cleaning process is performed at one place, and accordingly, the driving unevenness of the intermediate transfer belt 30 can be further reduced.

As described above, since the pressing force against the intermediate transfer belt 30 can be reduced, when the intermediate transfer belt 30 having a seam portion is used, the blades 62, The variation in the driving load of the intermediate transfer belt 30 due to 63 can be reduced, which is effective in suppressing the occurrence of color misregistration and banding. In the present embodiment, the combination of the fur brush 61 and the blades 62 and 63 is shown. However, by using only the fur brush 61, it is possible to further reduce the load fluctuation generated at the step portion of the seam portion. It is.

In the present embodiment, the fixing device 7
Reference numeral 0 denotes a pair of rolls composed of a heating roll 71 and a pressure roll 72, and its periphery is covered by a case 73 having openings on the entrance side and the exit side of the paper 100. The fixing device 70 is provided with the inclined portion 30 b of the intermediate transfer belt 30.
The entrance end of the case 73 of the fixing device 70 is displaced by a predetermined amount (indicated by d in FIG. 3) toward the collective transfer device 50 with respect to the belt cleaner 60. . At this time, even if a part of the collected toner drops from the belt cleaner 60, it does not drop directly onto the sheet 100 entering the fixing device 70 only by falling onto the case 73 of the fixing device 70. Therefore, the falling toner adheres to the sheet 100, and this is
And there is almost no concern that the image will be fixed after passing through. In particular, in the present embodiment, the belt cleaner 60 moves the paper 100 more than the fixing nip area of the fixing device 70.
, The toner is not spilled on the unfixed toner image.

Further, in the present embodiment, the batch transfer device 5
The transport path length S of the sheet 100 between the transfer area 0 and the fixing nip area of the fixing device 70 is set to be equal to or longer than the maximum sheet length (for example, JIS A3 longitudinal size in this embodiment). Furthermore, between the batch transfer device 50 and the fixing device 70, for example, two transports 81 and 82 for transporting the paper 100 are provided. The speed is adjusted so that it can be changed. In the inclined portion 30b of the intermediate transfer belt 30, near the collective transfer device 50, there is provided a separation error sensor 86 that optically detects a situation in which the paper 100 has passed while adhering to the surface of the intermediate transfer belt 30. .

FIG. 8 shows a system for realizing the speed control of the sheet 100 and the jam prevention control by the belt cleaner 60. In the figure, a control device 90 includes a paper thickness sensor 84 for detecting the thickness of the paper 100 to be used, for example, a pressure sensor, a thick paper mode switch 85 for selecting the use of thick paper, and a peeling error sensor 8.
6, and executes the speed control program or the jam prevention control program shown in FIG. 9 or FIG.
A control signal is sent to the transport drive motor 83 and the fixing device 70 or the belt drive motor 36. In the present embodiment, the transport drive motor 83 is driven and controlled independently of the fixing device 70 and the belt drive motor 36.

First, the speed control will be described.
As shown in the figure, when the paper thickness exceeds the standard,
The speeds of the transports 81 and 82 and the fixing device 70 are set to be lower than those of the intermediate transfer belt 30 to maintain good fixability to a sheet having a large heat capacity and a sheet thickness. The speed of the fixing device 70 and the speed of the fixing device 70 are set to the same speed as that of the intermediate transfer belt 30, and normal processing is performed.

FIG. 11 shows an example of a timing chart in which the speeds of the transports 81 and 82 and the fixing device 70 are set lower than those of the intermediate transfer belt 30. In the figure, first, the intermediate transfer belt 30 is rotated at a constant speed, and each color component toner image from each of the photosensitive drums 21a to 21d (for example, yellow (Y), magenta (M), cyan ( C) and black (K)) sequentially, and convey each image to the secondary transfer area. Then, the color component toner images are sequentially transferred to the paper 100 in the secondary transfer area,
Immediately before the paper 100 reaches the fixing nip area of the fixing device 70, the transports 81 and 82 are decelerated (V1 → V2).
To match the fixing deceleration speed. Further, when the trailing edge of the paper 100 passes through the transport 82 on the subsequent stage, the speeds of the transports 81 and 82 are increased to the standard speed (V1).
Match to the next paper 100 conveyance. Further, in the present embodiment, if the speed is independently controlled by the two divided transports 81 and 82, the time when the rear end of the paper 100 passes through the transport 81 of the preceding stage (secondary transfer side). Thus, the speed of the transport 81 can be adjusted to the standard speed, and the productivity in the deceleration mode can be further improved.

In particular, in this embodiment, the batch transfer device 5
Since the transport path length S of the paper 100 between the transfer area 0 and the fixing nip area of the fixing device 70 is set to be equal to or longer than the maximum size of the paper, the speed control of the maximum size paper according to the thickness is ensured. It is performed.

Next, the jam prevention control will be described. When an ON signal is input from the peeling error sensor 86,
The control device 90 determines that the sheet of the peeling error has adhered to the intermediate transfer belt 30, immediately stops the belt drive motor 36, and avoids the situation where the sheet 100 enters the belt cleaner 60 and jams.

Second Embodiment FIG. 12 shows an image forming apparatus according to a second embodiment. In the figure, the basic configuration of the image forming apparatus is substantially the same as that of the first embodiment, but is different from the first embodiment, and is further located between the transfer area by the collective transfer device 50 and the correction roll 33. Intermediate transfer belt 30
Inside, a contact roll 110 that contacts the inner surface of the intermediate transfer belt 30 is provided. Note that components similar to those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof is omitted here. The same applies to the following embodiments.

Therefore, according to the present embodiment, substantially the same operations and effects as those of the first embodiment are obtained, and the correction roll 3
3, the contact roll 1
Due to the presence of 10, the meandering restriction operation of the intermediate transfer belt 30 by the correction roll 33 is not directly transmitted to the transfer area of the collective transfer device 50, so that the meandering restriction operation by the correction roll 33 directly affects the collective transfer operation. Is effectively avoided.

Third Embodiment FIG. 13 shows an image forming apparatus according to a third embodiment. In FIG. 1, the basic configuration of the image forming apparatus is the same as that of the first embodiment.
However, different from the first embodiment, the inclined portion 30b is provided on the surface side of the inclined portion 30b of the intermediate transfer belt 30.
Roll 12 that is bent toward the straight portion 30a side
0, and further, the support roll 3 of the intermediate transfer belt 30
5, a type without the fur brush 61 is used as the belt cleaner 60, and the static eliminator 39 of the intermediate transfer belt 30 is further removed.

Therefore, according to the present embodiment, the angle θ between the intermediate transfer belt 30 located downstream of the transfer area of the batch transfer device 50 and the paper guide plate 102 is ensured by the bending roll 120. Therefore, the batch transfer device 50
The releasability of the paper 100 in the transfer area is maintained satisfactorily. In particular, in the present embodiment, when the intermediate transfer belt 30 is made of a material that requires static elimination, an AC bias of AC or DC superimposition is applied to the bending roll 120 so that the neutral transfer belt 30 is neutralized. It is possible to do. Further, if a bias having a polarity opposite to that of the toner is applied to the bending roll 120 such as when a paper jam occurs, the toner on the intermediate transfer belt 30 can be attracted to the bending roll 120 and pre-cleaned. The toner attached to the bending roll 120 may be collected by a separate cleaning blade 121. At this time,
Since the load on the belt cleaner 60 due to the untransferred toner is reduced, in this embodiment, the type of the belt cleaner 60 except for the fur brush is used, but the cleaning performance is kept good.

Fourth Embodiment FIG. 14 shows an image forming apparatus according to a fourth embodiment. In FIG. 1, the basic configuration of the image forming apparatus is the same as that of the first embodiment.
However, unlike the first embodiment, an auxiliary heat supply plate 130 in which, for example, heater wires are appropriately wired is disposed inside the transports 81 and 82, and the transport 8
Heat is supplementarily supplied to the sheet passing through the rollers 1 and 82. Therefore, in the present embodiment, even if the paper 100 or the toner image contains a lot of water, the water is evaporated by the auxiliary heat, and the water is removed before reaching the fixing device 70. Is done. For this reason, in a situation where the sheet 100 or the toner image contains a large amount of water, the fixing device 7 can be used without auxiliary heating.
When the image was rapidly heated in the fixing nip area of 0, image disturbance due to toner scattering phenomenon was observed. In the present embodiment, however, image disturbance due to this kind of toner scattering phenomenon is effectively eliminated. .

Fifth Embodiment FIG. 15 shows an image forming apparatus according to a fifth embodiment. In FIG. 1, the basic configuration of the image forming apparatus is the same as that of the first embodiment.
However, unlike the first embodiment, the transfer roll 51 of the batch transfer device 50 is forcibly driven by the drive motor 140. In particular, in the present embodiment, the driving device of the transfer roll 51 is as shown in FIG.
As shown in (b), the drive motor 140 and the transfer roll 5
1 is connected by a gear transmission system 141, and a torque limiter 142 is interposed in a part of the gear transmission system 141. When the transfer roll 51 exceeds the speed of the intermediate transfer belt 30, the torque limiter 142 is connected. To give priority to the speed of the intermediate transfer belt 30 over the transfer roll 51.

Therefore, in this embodiment, the sheet feeding and the transfer operation of the collective transfer device 50 are stably performed, and the rotation of the intermediate transfer belt 30 becomes unstable by the drive of the transfer roll 51. The situation is effectively avoided. Incidentally, the backup roll 52 (34) may be forcibly driven by the same means instead of the transfer roll 51, or the driving force of the belt drive motor 36 is reduced by the pulley 151 and the pulley 151 as shown in FIG. The drive may be transmitted to the backup roll 52 (34) by the belt 152 via the torque limiter 153 and the gear transmission system 154.

Sixth Embodiment FIG. 18 shows an image forming apparatus according to a sixth embodiment. In FIG. 1, the basic configuration of the image forming apparatus is the same as that of the first embodiment.
However, unlike the first embodiment, the layout of the batch transfer device 50 is further deviated to the downstream side of the linear portion 30a than the type of the first embodiment, and is fixed in a region below the inclined portion 30b. The device 70 and the belt cleaner 60 (however,
In the present embodiment, the fur brush 61 and one blade 6
2 is illustrated). Therefore, in the present embodiment, the width of the entire apparatus can be substantially set within the length of the intermediate transfer belt 30 in the moving direction.

FIG. 19 shows a layout example of the entire apparatus.
In FIG. 19, reference numerals 161 to 164 denote a paper feed cassette, 165 denotes a paper transport unit that transports paper from the paper feed cassettes 161 to 164 to a transfer area of the collective transfer device 50,
Reference numeral 6 denotes a sheet reversing unit for reversing the sheet after fixing during double-sided image formation. Reference numeral 167 denotes a sheet returning / conveying unit for returning the reversed sheet to the transfer area of the collective transfer device 50 again.

Seventh Embodiment FIG. 20 shows an image forming apparatus according to a seventh embodiment. In the figure, among the basic configurations of the image forming apparatus, the layout of the intermediate transfer belt 30, the batch transfer apparatus 50, the belt cleaner 60, and the fixing device 70 is substantially the same as that of the first embodiment. Unlike this, the intermediate transfer belt 30 that forms four color toner images in two cycles by two image forming units 200 (specifically, 200a and 200b) and rotates the color toner images formed in each cycle by two cycles. Are sequentially transferred to the printer.
Each image forming unit 200 includes a photosensitive drum 201
(Specifically, 201a and 201b) and a charging device 202 for charging the photosensitive drum 201 (specifically, 202
a, 202b) and an exposure device 203 for writing an electrostatic latent image on the charged photosensitive drum 201 (specifically, 203)
a, 203b) and two developing devices 20 for developing the electrostatic latent image formed on the photosensitive drum 201 with different toners.
4 (specifically, 204 a to 204 d) and a primary transfer device 205 (specifically, 205 a and 205 a) that primarily transfers each color toner image on the photosensitive drum 201 to the intermediate transfer belt 30.
05b) and a drum cleaner 206 (specifically, 206a, 206a) for removing the residual toner on each photosensitive drum 201.
06b) and the developing device 20 in the first cycle.
4a and 204b form toner images, and in the next cycle, toner images are formed by the developing devices 204c and 204d.

Further, in the present embodiment, the belt cleaner 60 is substantially the same as that of the first embodiment, but the cleaning point by the fur brush 61 and the blade 62
Is set smaller than the inter-image portion k between the residual toner image G1 after the batch transfer and the two-color toner image G2 in the first cycle, and the residual toner image G1 Immediately after the rear end passes the cleaning point of the blade 62, the belt cleaner 60 retracts from the cleaning position to the retracted position. In the present embodiment, only one transport 80 is provided between the collective transfer device 50 and the fixing device 70.

Therefore, in this embodiment, the four-color toner images are sequentially transferred to the intermediate transfer belt 30 by rotating each image forming unit 200 and the intermediate transfer belt 30 for two cycles, and the collective transfer device 50 is used. Paper 10 at
0 at a time. In such an operation process, the residual toner image G1 on the intermediate transfer belt 30 is cleaned by the belt cleaner 60 after the batch transfer, as shown in FIG. However, when image formation is performed continuously, a two-color toner image G2 is formed via the inter-image unit k after the four-color toner image. Therefore, as shown in FIG. 21B, the two-color toner image G2 passes through the belt cleaner 60 immediately after the cleaning process of the residual toner image G1 is completed. At this time, when left to set the belt cleaner 60 as it is click rie two <br/> ring position, since the two-color toner image G2 which is much trouble formed from being removed, the belt cleaner 60 is retracted to the retracted position There must be. In particular, since the span z between the cleaning points of the belt cleaner 60 is smaller than the inter-image portion k, the two-color toner image G2 still reaches the cleaning point of the belt cleaner 60 when the cleaning process of the residual toner image G1 is completed. do not do. Therefore, the residual toner image G
If the belt cleaner 60 is retracted to the retracted position after the completion of the first cleaning process, the destruction of the two-color toner image is easily prevented, and continuous image formation is realized.

FIG. 22 shows a layout example of the entire image forming apparatus according to the seventh embodiment.

[0057]

As described above, according to the present invention, the inclination of the intermediate transfer belt positioned between the transfer area of the batch transfer device and the support roll at the upstream end in the moving direction of the linear portion of the intermediate transfer belt is adjusted. A large space is secured below the portion, and at least a part of the fixing device is arranged in the space below the inclined portion, so that the side space of the intermediate transfer belt along the moving direction of the intermediate transfer belt is There is no need to secure space for the entire fixing device.
In addition to being able to reduce the size of the device in the width direction, it is also possible to secure a sufficient distance between the batch transfer device and the fixing device. The image forming process can be performed without reducing the speed of the transfer belt, and accordingly, productivity in a mode in which the fixing device for thick paper or the like is decelerated can be secured. Further, according to the present invention, since the superimposed image transferred on the intermediate transfer belt can reach the transfer area by the collective transfer device in a relatively short time, image disturbance in the conveyance process by the intermediate transfer belt is reduced. In addition, since the entry end of the recording material of the fixing device is displaced toward the collective transfer device with respect to the cleaning device, even if the image residue falls from the cleaning device, the image residue is removed. There is no direct drop on the recording material before fixing. For this reason, there is almost no concern that image quality defects occur in the recording material, and good image quality can be maintained at all times. Further, according to the present invention, the transfer area of the collective transfer device and the cleaning device can be sufficiently separated from each other. By detecting the separation error of the recording material, it is possible to prevent the recording material from being jammed in the cleaning device. Furthermore, according to the present invention, one
Transfer of transfer area and linear part of intermediate transfer belt by batch transfer device
The intermediate transfer belt located between the support roll at the downstream end in the movement direction.
Inside the belt, the direction of movement of the intermediate transfer belt is substantially
A compensating roll for meandering regulation in the crossing direction is arranged, and
Support roll at the upstream end in the moving direction of the linear portion of the intermediate transfer belt
In contrast, the correction roll is arranged more apart than other support rolls
Since the way, the intermediate transfer belts height dimension
Wrap the intermediate transfer belt around the correction roll without changing
A large protection area, and the belt
Intermediate rotation while meeting the demand for a flat knit
The meandering control operation of the photo belt can be reliably realized.
You.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating an outline of an image forming apparatus according to the present invention.

FIG. 2 is an explanatory diagram illustrating an outline of the image forming apparatus according to the first embodiment;

FIG. 3 is an explanatory diagram relating to a layout of the image forming apparatus according to the first embodiment;

FIG. 4 is an explanatory diagram showing details of a batch transfer device (secondary transfer device) used in the first embodiment.

FIG. 5 is a graph illustrating a relationship between an opening angle θ between a surface of an intermediate transfer belt located downstream of the collective transfer device and a guide conveyance plate surface of a recording material after collective transfer and a sheet peeling failure rate. is there.

FIG. 6 is a graph illustrating a relationship between a span between a transfer area of a batch transfer device and a sheet guide plate and a sheet peeling failure rate.

FIG. 7 is a graph showing a relationship between a driving roll diameter of the intermediate transfer belt and a minimum winding angle α.

FIG. 8 is a block diagram showing a control system of a drive motor.

FIG. 9 is a flowchart showing a speed control process used in the first embodiment.

FIG. 10 is a flowchart showing a jam prevention control process used in the first embodiment.

FIG. 11 is an explanatory diagram showing an example of a timing chart when the speeds of the transport and the fixing device are set to be slower in the speed control processing used in the first embodiment.

FIG. 12 is an explanatory diagram illustrating an outline of an image forming apparatus according to a second embodiment;

FIG. 13 is an explanatory diagram illustrating an outline of an image forming apparatus according to a third embodiment;

FIG. 14 is an explanatory diagram illustrating an outline of an image forming apparatus according to a fourth embodiment.

FIG. 15 is an explanatory diagram illustrating an outline of an image forming apparatus according to a fifth embodiment.

16A is an explanatory view showing a driving device of the collective transfer device, and FIG. 16B is a view of FIG.

FIG. 17 is an explanatory diagram showing another example of the driving device of the collective transfer device.

FIG. 18 is an explanatory diagram illustrating an outline of an image forming apparatus according to a sixth embodiment.

FIG. 19 is an explanatory diagram showing an example of the overall configuration of an image forming apparatus according to Embodiment 6.

FIG. 20 is an explanatory diagram illustrating an outline of an image forming apparatus according to a seventh embodiment.

FIGS. 21A and 21B are explanatory diagrams illustrating an operation example of the cleaning device used in the seventh embodiment.

FIG. 22 is an explanatory diagram showing an example of the overall configuration of an image forming apparatus according to a seventh embodiment.

[Explanation of symbols]

1 (1a to 1d): Image carrier, 2: Intermediate transfer belt, 2
a: linear portion, 2b: inclined portion, 3 (3a to 3c): support roll, 4: recording material, 5: batch transfer device, 6: cleaning device, 7: fixing device, 8: correction roll

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Keiji Yamamoto 2274 Hongo, Fujigo Rocks, Ebina-shi, Kanagawa Prefecture (72) Inventor Makoto Ochiai 2274 Hongo, Hongo, Ebina-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Masaaki Takahashi 2274 Hongo, Ebina-shi, Kanagawa Fuji Xerox Co., Ltd. (56) References JP-A-3-80276 (JP, A) JP-A-52-31190 (JP, A) JP-A-6-289686 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/16 G03G 15/00 550 G03G 15/01 114

Claims (22)

(57) [Claims] 1. A plurality of image carriers (1) on which a predetermined color component image is formed and supported and arranged in parallel, and are wound around at least three or more support rolls (3: 3a to 3c). An intermediate transfer belt (2) that circulates and moves along the arrangement direction of each image carrier (1) and temporarily transfers and holds each color component image on each image carrier (1); 2) is provided at a position corresponding to the support roll at the position furthest away from the linear portion (2a) extending substantially linearly along the arrangement direction of the image carriers (1) on the intermediate transfer belt (2). A collective transfer device (5) for collectively transferring the held color component images to the recording material (4); and an intermediate transfer belt after the collective transfer process to the recording material (4) by the collective transfer device (5) is completed. (2) a cleaning device (6) for removing the residue on the recording material; 4) a fixing device (7) for fixing each color component image collectively transferred onto the image forming device, wherein the fixing device (7) fixes the color component images on the intermediate transfer belt (2) along the arrangement direction of the image carriers (1). Intermediate transfer belt (2) of the straight portion (2a)
The transfer site of the batch transfer device (5) is deviated from the center position in the moving direction of the intermediate transfer belt (2) toward the downstream of the linear portion (2a). At least a part of the fixing device (7) is arranged in a space below the inclined portion (2b) of the intermediate transfer belt (2) located between the support roller (3a) at the upstream end in the moving direction of (2a) and the fixing device (7) rush end of the recording material (4) displaced disposed collective transfer device (5) side with respect to the cleaning device (6) of the further transfer area and the middle of the collective transfer device (5) Transfer bell
(2) The support row at the downstream end in the moving direction of the linear portion (2a)
(3b) and the intermediate transfer belt (2)
Side is substantially perpendicular to the moving direction of the intermediate transfer belt (2).
A correction roll (8) for meandering control in the direction of
First, the moving direction of the linear portion (2a) of the intermediate transfer belt (2)
The correction roll is provided for the support roll (3a) at the upstream end.
(8) is arranged more apart than other supporting rolls (3b, 3c)
An image forming apparatus characterized in that. 2. The image forming apparatus according to claim 1, wherein the cleaning device is disposed above the fixing nip area of the fixing device on the downstream side in the transport direction of the recording material. Characteristic image forming apparatus. 3. The image forming apparatus according to claim 1 , wherein the intermediate transfer belt is located between a transfer area of the batch transfer device and a correction roll. An image forming apparatus comprising: a contact member that contacts an inner surface of a belt (2). 4. The image forming apparatus according to claim 1, further comprising a support roll (3a) including a drive roll at an upstream end of the linear portion (2a) in the moving direction of the intermediate transfer belt (2).
The intermediate transfer belt (2) is supported by the support roll (3a).
A supporting roll (3b) composed of a driven roll, a meandering regulating correction roll (8) in a direction substantially perpendicular to the moving direction of the intermediate transfer belt (2), and
An image forming apparatus, wherein a batch transfer device (5) is sequentially arranged. 5. The image forming apparatus according to claim 4, wherein the winding area of the intermediate transfer belt is stretched so as to be larger with respect to a support roll composed of a driving roll and a correction roll. An image forming apparatus comprising: 6. The image forming apparatus according to claim 1, wherein a surface of the intermediate transfer belt (2) located downstream of the collective transfer device (5) and a guide conveying member surface of the recording material (4) after the collective transfer. An opening angle between the image forming apparatus and the image forming apparatus is set to 20 degrees or more. 7. The image forming apparatus according to claim 1, wherein a surface of the intermediate transfer belt (2) located downstream of the batch transfer device (5) and an intermediate transfer located upstream of the batch transfer device (5). An image forming apparatus, wherein an opening angle between the belt (2) and an extended surface is 10 degrees or more. 8. The image forming apparatus according to claim 1, wherein a transfer area of the batch transfer device and a support roll at an upstream end in a moving direction of the linear portion of the intermediate transfer belt. A curved roll in which the inclined portion (2b) is bent toward the linear portion (2a) is arranged in contact with the inclined portion (2b) surface side of the intermediate transfer belt (2) located therebetween. Image forming apparatus. 9. The image forming apparatus according to claim 1, wherein the conveying direction of the recording material after passing through the batch transfer device is relative to the linear portion of the intermediate transfer belt. An image forming apparatus, which is substantially parallel. 10. The image forming apparatus according to claim 1, wherein a conveying path of the recording material before and after the batch transfer device has a mountain shape having a transfer area at an apex. Forming equipment. 11. The image forming apparatus according to claim 1, wherein the batch transfer device (5) includes a roll that contacts the intermediate transfer belt (2) and is forcibly rotated by a driving device. Image forming device. 12. The image forming apparatus according to claim 11, wherein the driving device of the collective transfer device is a collective transfer device.
An image forming apparatus characterized in that an overload prevention mechanism is provided in a driving force transmission mechanism between the power source and the driving source. 13. The image forming apparatus according to claim 1, wherein the cleaning device has a plurality of scraping members that come into contact with a surface of the intermediate transfer belt, and faces the scraping members. An image forming apparatus comprising a plurality of backup rolls disposed on the back side of an intermediate transfer belt (2). 14. The image forming apparatus according to claim 13, wherein the cleaning device includes a cleaning position at which the scraping member contacts the intermediate transfer belt, and a retracting position at which the cleaning member retracts from the intermediate transfer belt. Wherein the span between the plurality of scraping members is set shorter than the span of the inter-image portion on the intermediate transfer belt (2). apparatus. 15. The image forming apparatus according to claim 1, wherein the cleaning device includes a scraping member made of a fur brush that contacts a surface of the intermediate transfer belt. Forming equipment. 16. The image forming apparatus according to claim 1, wherein the cleaning device has a plurality of scraping members that come into contact with a surface of the intermediate transfer belt, and the intermediate transfer belt. An image forming apparatus, wherein the scraping member located on the upstream side in the movement direction of the intermediate transfer belt is constituted by a fur brush that comes into contact with the surface of the intermediate transfer belt (2). 17. The image forming apparatus according to claim 1, wherein a distance between a transfer area of the collective transfer device and a fixing nip area of the fixing device is conveyable. The image forming apparatus is set to be longer. 18. The image forming apparatus according to claim 1, wherein auxiliary heat is supplied to the recording material (4) in the vicinity of a conveyance path of the recording material (4) to the fixing device (7). An image forming apparatus provided with a supply device. 19. The image forming apparatus according to claim 1, wherein the conveying speed of the recording material (4) after passing through the batch transfer device (5) is changed according to the type of the recording material (4). An image forming apparatus comprising the apparatus. 20. An image forming apparatus according to claim 19 , wherein one or a plurality of recording material conveying members are provided between the collective transfer device (5) and the fixing device (7). A mode in which the speed of the device (7) is changed from that of the intermediate transfer belt (2), and the speed of the recording material transporting body can be controlled independently of the intermediate transfer belt (2) and the fixing device (7). Characteristic image forming apparatus. 21. A plurality of image carriers (1) on which predetermined color component images are formed and supported and arranged in parallel, and are wound around at least three or more support rolls (3: 3a to 3c). An intermediate transfer belt (2) that circulates and moves along the arrangement direction of each image carrier (1) and temporarily transfers and holds each color component image on each image carrier (1); 2) is provided at a position corresponding to the support roll at the position furthest away from the linear portion (2a) extending substantially linearly along the arrangement direction of the image carriers (1) on the intermediate transfer belt (2). A collective transfer device (5) for collectively transferring the held color component images to the recording material (4); and an intermediate transfer belt after the collective transfer process to the recording material (4) by the collective transfer device (5) is completed. (2) a cleaning device (6) for removing the residue above, and recording And (4) a fixing device (7) for fixing the color component images collectively transferred on the image transfer device, wherein the fixing device (7) fixes the color component images on the intermediate transfer belt (2) in the direction in which the image carriers (1) are arranged. Intermediate transfer belt (2) of the linear portion (2a) along
The transfer area of the batch transfer device (5) is deviated from the center in the movement direction of the linear transfer portion (2a) toward the downstream of the linear portion (2a). The fixing device (7) is disposed in a space below the inclined portion (2b) of the intermediate transfer belt (2) located between the support roller (3a) at the upstream end in the moving direction of (2a) , and further, batch transfer. Transfer area and intermediate transfer bell by device (5)
(2) The support row at the downstream end in the moving direction of the linear portion (2a)
(3b) and the intermediate transfer belt (2)
Side is substantially perpendicular to the moving direction of the intermediate transfer belt (2).
A correction roll (8) for meandering control in the direction of
First, the moving direction of the linear portion (2a) of the intermediate transfer belt (2)
The correction roll is provided with respect to the upstream end support roll
(8) is arranged more apart than other supporting rolls (3b, 3c)
An image forming apparatus characterized in that. 22. The image forming apparatus according to claim 21, further comprising a cleaning device (6) disposed in a space below the inclined portion (2b) of the intermediate transfer belt (2). Forming equipment.